WorldWideScience

Sample records for satellite concept evaluation

  1. The Federated Satellite Systems paradigm: Concept and business case evaluation

    Science.gov (United States)

    Golkar, Alessandro; Lluch i Cruz, Ignasi

    2015-06-01

    This paper defines the paradigm of Federated Satellite Systems (FSS) as a novel distributed space systems architecture. FSS are networks of spacecraft trading previously inefficiently allocated and unused resources such as downlink bandwidth, storage, processing power, and instrument time. FSS holds the promise to enhance cost-effectiveness, performance and reliability of existing and future space missions, by networking different missions and effectively creating a pool of resources to exchange between participants in the federation. This paper introduces and describes the FSS paradigm, and develops an approach integrating mission analysis and economic assessments to evaluate the feasibility of the business case of FSS. The approach is demonstrated on a case study on opportunities enabled by FSS to enhance space exploration programs, with particular reference to the International Space Station. The application of the proposed methodology shows that the FSS concept is potentially able to create large commercial markets of in-space resources, by providing the technical platform to offer the opportunity for spacecraft to share or make use of unused resources within their orbital neighborhood. It is shown how the concept is beneficial to satellite operators, space agencies, and other stakeholders of the space industry to more flexibly interoperate space systems as a portfolio of assets, allowing unprecedented collaboration among heterogeneous types of missions.

  2. Satellite power system. Concept development and evaluation program

    Energy Technology Data Exchange (ETDEWEB)

    1978-10-01

    The Reference System description emphasizes technical and operational information required in support of environmental, socioeconomic, and comparative assessment studies. Supporting information has been developed according to a guideline of implementing two 5 GW SPS systems per year for 30 years beginning with an initial operational data of 2000 and with SPS's being added at the rate of two per year (10 GW/year) until 2030. The Reference System concept, which features gallium--aluminum--arsenide (GaAlAs) and silicon solar cell options, is described in detail. The concept utilizes a planar solar array (about 55 km/sup 2/) built on a graphite fiber reinforced thermoplastic structure. The silicon array uses a concentration ratio of one (no concentration), whereas the GaAlAs array uses a concentration ratio of two. A one-kilometer diameter phased array microwave antenna is mounted on one end. The antenna uses klystrons as power amplifiers with slotted waveguides as radiating elements. The satellite is constructed in geosynchronous orbit in a six-month period. The ground receiving stations (rectenna) are completed during the same time period. The other two major components of an SPS program are (1) the construction bases in space and launch and mission control bases on earth and (2) fleets of various transportation vehicles that support the construction and maintenance operations of the satellites. These transportation vehicles include Heavy Lift Launch Vehicles (HLLV), Personnel Launch Vehicles (PLV), Cargo Orbit Transfer Vehicles (COTV), and Personnel Orbit Transfer Vehicles (POTV). The earth launch site chosen is the Kennedy Space Center, pending further study.

  3. Environmental assessment for the satellite power system concept development and evaluation program: atmospheric effects

    Energy Technology Data Exchange (ETDEWEB)

    Rote, D.M.; Brubaker, K.L.; Lee, J.L.

    1980-11-01

    The US Department of Energy (DOE) has undertaken a preliminary, three-year program to investigate the impacts of the construction and operation of a satellite power system, of unprecedented scale. The Department of Energy's program, titled The Concept Development and Evaluation Program, focused its investigations on a Reference System description that calls for the use of either silicon (Si) or gallium aluminum-arsenide (GaAlAs) photovoltaic cells on 60 satellites to be constructed in GEO over a 30-yr period. Rectennas would be constructed on the ground to receive microwave energy from the satellites. Each satellite-rectenna pair is designed to produce 5 GW of power on an essentially continuous basis for use as a baseload power source for an electric power distribution system. The environmental assessment part of the program was divided into five interdependent task areas. The present document constitutes the final technical report on one of the five task areas, the Assessment of the Atmospheric Effects, and as such presents an in-depth summary of work performed during the assessment program. The issues associated with SPS activities in the troposphere are examined. These include tropospheric weather modification related to rectenna operations and rocket launches, and air quality impacts related to rocketlaunch ground clouds. Then progressing upward through the various levels of the atmosphere, the principal middle and upper atmospheric effects associated with rocket effluents are analyzed. Finally, all of the potential SPS atmospheric effects are summarized.

  4. Program assessment report, statement of findings. Satellite power systems concept development and evaluation program

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-11-01

    What is known, uncertain, and unknown about the Solar Power Satellite (SPS) concept is stated. The important technical, environmental, and cost goal questions that must be answered prior to making a commitment to the SPS concept are discussed. Although significant technological, environmental and economic questions remain to be answered, the preliminary investigations undertaken in the CDEP do provide a basis for a policy decision on further commitment. Also, areas of research and experimentation required to acquire the knowledge by which a series of informed, time-phased decisions may be made concerning the possibility of the SPS concept playing a major role in the United States' energy future are suggested.

  5. Satellite power system concept development and evaluation program system definition technical assessment report

    Energy Technology Data Exchange (ETDEWEB)

    1980-12-01

    The results of the system definition studies conducted by NASA as a part of the Department of Energy/National Aeronautics and Space Administration SPS Concept Development and Evaluation Program are summarized. The purpose of the system definition efforts was to identify and define candidate SPS concepts and to evaluate the concepts in terms of technical and cost factors. Although the system definition efforts consisted primarily of evaluation and assessment of alternative technical approaches, a reference system was also defined to facilitate economic, environmental, and societal assessments by the Department of Energy. This reference system was designed to deliver 5 GW of electrical power to the utility grid. Topics covered include system definition; energy conversion and power management; power transmission and reception; structures, controls, and materials; construction and operations; and space transportation.

  6. Environmental assessment for the satellite power system concept development and evaluation program: nonmicrowave health and ecological effects

    Energy Technology Data Exchange (ETDEWEB)

    White, M R

    1980-11-01

    A Concept Development and Evaluation Program is being carried out for a proposed Satellite Power System (SPS). For purposes of this evaluation, a preliminary reference system has been developed. SPS, as described in the reference system, would collect solar energy on satellites in geosychronous orbit in space. The energy would be converted to microwaves and beamed to an earth-receiving antenna (rectenna). One task in the environmental part of the program is the assessment of the nonmicrowave effects on health and the environment. These effects would result from all phases of SPS development and operation. This report covers the current knowledge regarding these effects, and is based on the reference system. The assessment is summarized as to scope, methodology, impacts of terrestrial development, launch and recovery of spacecraft, space activities (including health effects of the space environment, ionizing radiation, electromagnetic exposure, spacecraft charging and environmental interactions, occupational hazards, etc.) and construction and operation of rectenna (ground receiving station).

  7. Environmental assessment for the satellite power system concept development and evaluation program-electromagnetic systems compatibility

    Energy Technology Data Exchange (ETDEWEB)

    Davis, K A; Grant, W B; Morrison, E L; Juroshek, J R

    1981-01-01

    The EMC analysis addressed only the direct effects of electromagnetic emissions from the SPS on other technological systems. Emissions were defined quite broadly, including not only those from the microwave system, but also thermal blackbody emission and scattered sunlight from the satellite. The analysis is based on the design for an SPS as described in the Reference System Report and some quantitative conclusions, e.g., ranges from rectenna sites at which effects are expected are specific to that design. The methodology and qualitative conclusions, however, apply to an SPS concept using microwave power transmission. Quantitative conclusions have been obtained parametrically and can be adjusted as SPS designs change. The electromagnetic environment that the Reference System would produce, and in which other systems would have to function, is described. As an early part of the EMC Assessment, the problems expected for a hypothetical rectenna site, in the Mojave Desert of southern California, were analyzed in detail. This effort provided an initial quantitative indication of the scope of potential EMC problems and indicated the importance of EMC considerations in rectenna site selection. The results of this analysis are presented. The effects of SPS microwave emissions on important categories of electronic systems and equipment are summarized, with many examples of test results and demonstrated techniques for mitigation of problems encountered. SPS effects on other satellite systems are presented. Astronomical research frequently involves measurement of extremely low levels of electromagnetic radiation and is thus very susceptible to interference. The concerns of both radio astronomy with microwave emissions from SPS and optical astronomy with sunlight scattered from SPS spacecraft are discussed. Summaries of mitigation techniques, cost estimates, and conclusions are presented. (WHK)

  8. Ravens satellite mission concept study

    CERN Document Server

    Donovan, Eric F

    2011-01-01

    The concept for Ravens satellite mission was proposed in response to a CSA AO for potential Canadian mission contributions to the International Living With a Star (ILWS) program. Ravens was conceived of to fill an important gap in the ILWS program: global imaging. Ravens will build on the heritage of world-class global imaging carried out in Canada. It would do much more than provide global observations to complete the system level capabilities of ILWS. Ravens would be comprised of two satellites on elliptical polar orbits, relatively phased on those orbits to provide the first-ever continuous (ie., 24 hours per day 7 days per week) global imaging of the northern hemisphere auroral and polar cap regions. This would provide the first-ever unbroken sequences of global images of the auroral response during long duration geomagnetic processes like storms and steady magnetospheric convection events. Ravens could track the spatio-temporal evolution of the global electron and proton auroral distribution, and would o...

  9. Formation Flying/Satellite Swarm Concept Project

    Science.gov (United States)

    Youngquist, Robert C.

    2014-01-01

    NASA needs a method of not only propelling and rotating small satellites, but also to track their position and orientation. We propose a concept that will, for the first time, demonstrate both tracking and propulsion simultaneously in the same system.

  10. Environmental assessment for the satellite power system-concept development and evaluation program-microwave health and ecological effects

    Science.gov (United States)

    1980-01-01

    Potential health and ecological effects of the microwave beam from the microwave power transmission system (MPTS) of the satellite power system (SPS) are discussed. A detailed critical review of selected scientific articles from the published literature on the biological effects of nonionizing electromagnetic radiation is provided followed by an assessment of the possible effects of the SPS, based on exposure values for the reference system.

  11. Environmental assessment for the satellite power system-concept development and evaluation program-microwave health and ecological effects

    Energy Technology Data Exchange (ETDEWEB)

    1980-11-01

    This report is concerned with the potential health and ecological effects of the microwave beam from the microwave power transmission system (MPTS) of the satellite power system (SPS). The report is written in the form of a detailed critical review of selected scientific articles from the published literature on the biological effects of nonionizing electromagnetic radiation, followed by an assessment of the possible effects of the SPS, based on exposure values for the reference system (US DOE and NASA, 1978).

  12. Satellite systems for personal applications concepts and technology

    CERN Document Server

    Richharia, Madhavendra

    2010-01-01

    Presents the concepts, technology, and role of satellite systems in support of personal applications, such as mobile and broadband communications, navigation, television, radio and multimedia broadcasting, safety of life services, etc. This book presents a novel perspective on satellite systems, reflecting the modern personal technology context, and hence a focus on the individual as end-user. The book begins by outlining key generic concepts before discussing techniques adopted in particular application areas; next, it exemplifies these techniques through discussion of state-of-art c

  13. Concept of an Effective Sentinel-1 Satellite SAR Interferometry System

    OpenAIRE

    2016-01-01

    This brief study introduces a partially working concept being developed at IT4Innovations supercomputer (HPC) facility. This concept consists of several modules that form a whole body of an efficient system for observation of terrain or objects displacements using satellite SAR interferometry (InSAR). A metadata database helps to locate data stored in various storages and to perform basic analyzes. A special database has been designed to describe Sentinel-1 data, on its burst level. Custom Se...

  14. Environmental assessment for the Satellite Power System (SPS) Concept Development and Evaluation Program (CDEP). [Microwave and non-microwave health and ecological assessment

    Energy Technology Data Exchange (ETDEWEB)

    Valentino, A.R.

    1980-08-01

    In the satellite power system (SPS), satellites in geosynchronous earth orbit would collect solar energy in space, convert it to microwaves, and transmit the microwaves to receiving antennas (rectennas) on earth. At the rectennas, the microwave energy would be converted to electricity. This SPS environmental assessment considers the microwave and nonmicrowave effects on the terrestrial environment and human health, atmospheric effects, and effects on electromagnetic systems. No environmental problem has been identified that would preclude the continued study of SPS technology. To increase the certainty of the assessment, some research has been initiated and long-term research is being planned.

  15. Solar Thermal Concept Evaluation

    Science.gov (United States)

    Hawk, Clark W.; Bonometti, Joseph A.

    1995-01-01

    Concentrated solar thermal energy can be utilized in a variety of high temperature applications for both terrestrial and space environments. In each application, knowledge of the collector and absorber's heat exchange interaction is required. To understand this coupled mechanism, various concentrator types and geometries, as well as, their relationship to the physical absorber mechanics were investigated. To conduct experimental tests various parts of a 5,000 watt, thermal concentrator, facility were made and evaluated. This was in anticipation at a larger NASA facility proposed for construction. Although much of the work centered on solar thermal propulsion for an upper stage (less than one pound thrust range), the information generated and the facility's capabilities are applicable to material processing, power generation and similar uses. The numerical calculations used to design the laboratory mirror and the procedure for evaluating other solar collectors are presented here. The mirror design is based on a hexagonal faceted system, which uses a spherical approximation to the parabolic surface. The work began with a few two dimensional estimates and continued with a full, three dimensional, numerical algorithm written in FORTRAN code. This was compared to a full geometry, ray trace program, BEAM 4, which optimizes the curvatures, based on purely optical considerations. Founded on numerical results, the characteristics of a faceted concentrator were construed. The numerical methodologies themselves were evaluated and categorized. As a result, the three-dimensional FORTRAN code was the method chosen to construct the mirrors, due to its overall accuracy and superior results to the ray trace program. This information is being used to fabricate and subsequently, laser map the actual mirror surfaces. Evaluation of concentrator mirrors, thermal applications and scaling the results of the 10 foot diameter mirror to a much larger concentrator, were studied. Evaluations

  16. Concept of nondestructive evaluation

    Science.gov (United States)

    Chern, E. J.

    1991-01-01

    The history of nondestructive evaluation, a recently evolved basic testing philosophy, and some application of NDE are examined with emphasis on aerospace applications. The discussion covers the definition of NDE, chronological development, NDE methods and systems, the use of NDE for process control, NDE for ceramics and composites, NDE for fracture control in glass, and science aspects of NDE. Specific examples of NDE applications are given.

  17. Satellite switching concepts for European business services in the nineties

    Science.gov (United States)

    Lombard, D.; Rouffet, D.

    A first generation of business communication satellites are now operational or to be launched. Increased demands for communication satellite facilities will develop, if special services, such as videoconferencing, can be provided at a reasonable cost. For such developments, it will be necessary to define a second generation of business communication satellites. The present investigation evaluates briefly the size of the expected European market for 1995. A study is conducted of the payload structure for the required satellite system, and aspects related to link budgets and power consumption are explored. It is found that system dimensioning is determined by the up-link and by technology. Critical factors are related to the output and input multiplexors for the link budget, the switching matrix, and implications for the mass budget. The best trade-off between technological, mass, and link budget limitations is achieved in connection with the employment of a hinged antennas satellite, using an intermediate number of spot beams and associated earth stations of reasonable size.

  18. a Technical Overview of the "suntower" Solar Power Satellite Concept

    Science.gov (United States)

    Mankins, John C.

    2002-03-01

    During 1995-1996, the National Aeronautics and Space Administration (NASA) conducted a far-reaching reexamination of the technologies, systems concepts and terrestrial markets that might be involved in future space solar power (SSP) systems. The principal objective of this "fresh look" study was to determine whether a solar power satellite (SPS) and associated systems could be defined that could deliver energy into terrestrial electrical power grids at prices equal to or below ground alternatives in a variety of markets, do so without major environmental drawbacks, and which could be developed at a fraction of the initial investment projected for the SPS Reference System of the late 1970s. One of the key concepts emerging from the "fresh look" SSP study is the "SunTower" SPS system. This concept exploits a variety of innovative technologies and design approaches to achieve a potential breakthrough in establishing the technical and programmatic feasibility on initial commercial SSP operations. Capable of being deployed to either low Earth orbit or middle Earth orbit altitudes and various inclinations, the SunTower concept involves essentially no in-space infrastructure and requires no unique heavy lift launch vehicle. The concept, which can provide power to global market places appears to allow up to a factor of 30:1 reduction in initial investment requirements, compared to the 1979 SPS Reference Concept. This paper presents a technical overview of the SunTower SPS concept, including key technologies, sensitivity trades, operational scenarios. Potential non-SPS space program uses of the SunTower concept and related technologies are identified, including human exploration, space science and commercial space applications.

  19. Concepts and cost trade-offs for land vehicle antennas in satellite mobile communications

    Science.gov (United States)

    Haddad, H. A.

    1948-01-01

    Several antenna design concepts, operating at UHF (821 to 825 MHz transmit and 866 to 870 MHz receive bands), with gain ranging between 6 and 12 dBic, that are suitable for land mobile vehicles are presented. The antennas may be used within CONUS and ALASKA to communicate to and from a geosynchronous satellite. Depending on the type of steering mechanism, the antennas are broken down into three categories; (1) electronically scanned arrays with phase shifters, (2) electronically switched arrays with switchable power dividers/combiners, and (3) mechanically steered arrays. The operating characteristics of two of these design concepts, one a conformal antenna with electronic beam steering and the other a nonconformal design with mechanical steering, were evaluated with regard to two and three satellite system. Cost estimates of various antenna concepts were made and plotted against their overall gain performance.

  20. A European mobile satellite system concept exploiting CDMA and OBP

    Science.gov (United States)

    Vernucci, A.; Craig, A. D.

    1993-01-01

    This paper describes a novel Land Mobile Satellite System (LMSS) concept applicable to networks allowing access to a large number of gateway stations ('Hubs'), utilizing low-cost Very Small Aperture Terminals (VSAT's). Efficient operation of the Forward-Link (FL) repeater can be achieved by adopting a synchronous Code Division Multiple Access (CDMA) technique, whereby inter-code interference (self-noise) is virtually eliminated by synchronizing orthogonal codes. However, with a transparent FL repeater, the requirements imposed by the highly decentralized ground segment can lead to significant efficiency losses. The adoption of a FL On-Board Processing (OBP) repeater is proposed as a means of largely recovering this efficiency impairment. The paper describes the network architecture, the system design and performance, the OBP functions and impact on implementation. The proposed concept, applicable to a future generation of the European LMSS, was developed in the context of a European Space Agency (ESA) study contract.

  1. Evaluating NOx Emissions Using Satellite Observations

    Science.gov (United States)

    Frost, G. J.; Kim, S.; Brioude, J.; McKeen, S. A.; Trainer, M.; Heckel, A.; Hilboll, A.; Richter, A.; Burrows, J. P.; Gleason, J. F.; Boersma, K. F.; Hsie, E.; Lee, S.; Angevine, W. M.; Granier, C.; Peischl, J.; Ryerson, T. B.; Fehsenfeld, F. C.

    2012-12-01

    Atmospheric NO2 columns retrieved from satellites can provide a useful top-down assessment of bottom-up NOx emissions inventories. We present three case studies of an approach to evaluate NOx emissions at a sector level by comparing satellite retrievals to regional chemical-transport model calculations of NO2 columns. In the first example, the atmospheric impact of implementing NOx controls at eastern US power plants is demonstrated. In the second study, we use NOx monitors at western US power plants to calibrate our satellite-model comparisons. We then apply our approach to evaluate bottom-up estimates of NOx emissions from western US cities. In the third example, we validate our satellite-model approach using in-situ aircraft measurements and assess NOx emissions from power plants, cities, industrial facilities, and ports in eastern Texas. We conclude with some general insights on the usefulness of this approach and suggestions for future areas of research.

  2. Satellite Power Systems (SPS) concept definition study. Volume 4: SPS point design definition

    Science.gov (United States)

    Hanley, G.

    1978-01-01

    The satellite power systems point design concept is described. The concept definition includes satellite, ground and space systems, and their relationships. Emphasis is placed on the definition of the GaAlAs photovoltaic satellite system. The major subsystems of the satellite system including power conversion, power distribution and control, microwave, attitude control and stationkeeping, thermal control, structures, and information management and control are discussed.

  3. Progressive Concept Evaluation Method for Automatically Generated Concept Variants

    Directory of Open Access Journals (Sweden)

    Woldemichael Dereje Engida

    2014-07-01

    Full Text Available Conceptual design is one of the most critical and important phases of design process with least computer support system. Conceptual design support tool (CDST is a conceptual design support system developed to automatically generate concepts for each subfunction in functional structure. The automated concept generation process results in large number of concept variants which require a thorough evaluation process to select the best design. To address this, a progressive concept evaluation technique consisting of absolute comparison, concept screening and weighted decision matrix using analytical hierarchy process (AHP is proposed to eliminate infeasible concepts at each stage. The software implementation of the proposed method is demonstrated.

  4. The German joint research project "concepts for future gravity satellite missions"

    Science.gov (United States)

    Reubelt, Tilo; Sneeuw, Nico; Fichter, Walter; Müller, Jürgen

    2010-05-01

    Within the German joint research project "concepts for future gravity satellite missions", funded by the Geotechnologies programme of the German Federal Ministry of Education and Research, options and concepts for future satellite missions for precise (time-variable) gravity field recovery are investigated. The project team is composed of members from science and industry, bringing together experts in geodesy, satellite systems, metrology, sensor technology and control systems. The majority of team members already contributed to former gravity missions. The composition of the team guarantees that not only geodetic aspects and objectives are investigated, but also technological and financial constraints are considered. Conversely, satellite, sensor and system concepts are developed and improved in a direct exchange with geodetic and scientific claims. The project aims to develop concepts for both near and mid-term future satellite missions, taking into account e.g. advanced satellite formations and constellations, improved orbit design, innovative metrology and sensor systems and advances in satellite systems.

  5. Satellite Power Systems (SPS) concept definition study. Volume 5: Special emphasis studies. [rectenna and solar power satellite design studies

    Science.gov (United States)

    Hanley, G. M.

    1980-01-01

    Satellite configurations based on the Satellite Power System baseline requirements were analyzed and a preferred concept selected. A satellite construction base was defined, precursor operations incident to establishment of orbital support facilities identified, and the satellite construction sequence and procedures developed. Rectenna construction requirement were also addressed. Mass flow to orbit requirements were revised and traffic models established based on construction of 60 instead of 120 satellites. Analyses were conducted to determine satellite control, resources, manufacturing, and propellant requirements. The impact of the laser beam used for space-to-Earth power transmission upon the intervening atmosphere was examined as well as the inverse effect. The significant space environments and their effects on spacecraft components were investigated to define the design and operational limits imposed by the environments on an orbit transfer vehicle. The results show that LEO altitude 300 nmi and transfer orbit duration 6 months are preferrable.

  6. Phase control system concepts and simulations. [solar power satellite system

    Science.gov (United States)

    Lindsay, V. C.

    1980-01-01

    A phase control system concept for a solar power satellite is proposed which partitions the system into three major levels. The first level of phase control consists of a reference phase distribution system implemented in the form of phase distribution tree structure. The major purpose of the tree structure is to electronically compensate for the phase shift due to the transition path lengths from the center of the spacetenna to each phase control center located in each subarray. In the reference system, this is accomplished using the master slave returnable timing system technique. The second level of phase control consists of the beam steering and microwave power generating system which houses the power transponders. This transponder consists of a set of phase conjugation multipliers driven by the reference phase distribution system output and the output of a pilot spread spectrum receiver which accepts the received pilot via a diplexer connected to a separate receive horn or the subarray itself. The output of the phase conjugation circuits serve as inputs to the third level of the phase control system. The third level of phase control is associated with maintaining an equal and constant phase shift through the microwave power amplifier devices while minimizing the associated phase noise effects on the generated power beam. This is accomplished by providing a phase locked loop around each high power amplifier.

  7. Satellite Ocean Color Sensor Design Concepts and Performance Requirements

    Science.gov (United States)

    McClain, Charles R.; Meister, Gerhard; Monosmith, Bryan

    2014-01-01

    800 nanometers with three additional discrete near infrared (NIR) and shortwave infrared (SWIR) ocean aerosol correction bands. Also, to avoid drift in sensor sensitivity from being interpreted as environmental change, climate change research requires rigorous monitoring of sensor stability. For SeaWiFS, monthly lunar imaging accurately tracked stability at an accuracy of approximately 0.1% that allowed the data to be used for climate studies [2]. It is now acknowledged by the international community that future missions and sensor designs need to accommodate lunar calibrations. An overview of ocean color remote sensing and a review of the progress made in ocean color remote sensing and the variety of research applications derived from global satellite ocean color data are provided. The purpose of this chapter is to discuss the design options for ocean color satellite radiometers, performance and testing criteria, and sensor components (optics, detectors, electronics, etc.) that must be integrated into an instrument concept. These ultimately dictate the quality and quantity of data that can be delivered as a trade against mission cost. Historically, science and sensor technology have advanced in a "leap-frog" manner in that sensor design requirements for a mission are defined many years before a sensor is launched and by the end of the mission, perhaps 15-20 years later, science applications and requirements are well beyond the capabilities of the sensor. Section 3 provides a summary of historical mission science objectives and sensor requirements. This progression is expected to continue in the future as long as sensor costs can be constrained to affordable levels and still allow the incorporation of new technologies without incurring unacceptable risk to mission success. The IOCCG Report Number 13 discusses future ocean biology mission Level-1 requirements in depth.

  8. Satellite-aided mobile radio concepts study: Concept definition of a satellite-aided mobile and personal radio communication system

    Science.gov (United States)

    Anderson, R. E.

    1979-01-01

    The satellite system requires the use of a large satellite antenna and spacecraft array power of about 12 kW or more depending on the operating frequency. Technology developments needed include large offset reflector multibeam antennas, satellite electrical power sybsystems providing greater than 12 kW of power, signal switching hardware, and linearized efficient solid state amplifiers for the satellite-aided mobile band. Presently there is no frequency assignment for this service, and it is recommended that an allocation be pursued. The satellite system appears to be within reasonable extrapolation of the state of the art. It is further recommended that the satellite-aided system spacecraft definition studies and supporting technology development be initiated.

  9. Philosophy and key features of 'Hodoyoshi' concept for optical remote sensing using 50kg class satellites

    Science.gov (United States)

    Enokuchi, A.; Takeyama, N.; Nakamura, Y.; Nojiri, Y.; Miyamura, N.; Iwasaki, A.; Nakasuka, S.

    2010-10-01

    Remote sensing missions have been conventionally performed by using satellite-onboard optical sensors with extraordinarily high reliability, on huge satellites. On the other hand, small satellites for remote-sensing missions have recently been developed intensely and operated all over the world. This paper gives a Japanese concept of the development of nano-satellites(10kg to 50kg) based on "Hodoyoshi" (Japanese word for "reasonable") reliability engineering aiming at cost-effective design of optical sensors, buses and satellites. The concept is named as "Hodoyoshi" concept. We focus on the philosophy and the key features of the concept. These are conveniently applicable to the development of optical sensors on nano-satellites. As major advantages, the optical sensors based on the "Hodoyoshi" concept are "flexible" in terms of selectability of wavelength bands, adaptability to the required ground sample distance, and optimal performance under a wide range of environmental temperatures. The first and second features mentioned above can be realized by dividing the functions of the optical sensor into modularized functional groups reasonably. The third feature becomes possible by adopting the athermal and apochromatic optics design. By utilizing these features, the development of the optical sensors become possible without exact information on the launcher or the orbit. Furthermore, this philosophy leads to truly quick delivery of nano-satellites for remote-sensing missions. On the basis of the concept, we are now developing nano-satellite technologies and five nano-satellites to realize the concept in a four-year-long governmentally funded project. In this paper, the specification of the optical sensor on the first satellite is also reported.

  10. Evaluating the hydrological consistency of satellite based water cycle components

    KAUST Repository

    Lopez Valencia, Oliver M.

    2016-06-15

    Advances in multi-satellite based observations of the earth system have provided the capacity to retrieve information across a wide-range of land surface hydrological components and provided an opportunity to characterize terrestrial processes from a completely new perspective. Given the spatial advantage that space-based observations offer, several regional-to-global scale products have been developed, offering insights into the multi-scale behaviour and variability of hydrological states and fluxes. However, one of the key challenges in the use of satellite-based products is characterizing the degree to which they provide realistic and representative estimates of the underlying retrieval: that is, how accurate are the hydrological components derived from satellite observations? The challenge is intrinsically linked to issues of scale, since the availability of high-quality in-situ data is limited, and even where it does exist, is generally not commensurate to the resolution of the satellite observation. Basin-scale studies have shown considerable variability in achieving water budget closure with any degree of accuracy using satellite estimates of the water cycle. In order to assess the suitability of this type of approach for evaluating hydrological observations, it makes sense to first test it over environments with restricted hydrological inputs, before applying it to more hydrological complex basins. Here we explore the concept of hydrological consistency, i.e. the physical considerations that the water budget impose on the hydrologic fluxes and states to be temporally and spatially linked, to evaluate the reproduction of a set of large-scale evaporation (E) products by using a combination of satellite rainfall (P) and Gravity Recovery and Climate Experiment (GRACE) observations of storage change, focusing on arid and semi-arid environments, where the hydrological flows can be more realistically described. Our results indicate no persistent hydrological

  11. A New Formation Flying/Satellite Swarm Concept Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA plans to build a lab bench operational system capable of tracking the position and orientation of small satellites as well as producing forces and torques on...

  12. CONCEPT MAPS: LEARNING AND EVALUATION PROPOSALS

    Directory of Open Access Journals (Sweden)

    Edson Coutinho da Silva

    2015-12-01

    Full Text Available Concept maps are graphical tools for organizing and representing knowledge. They are employed in conjunction with a proposal to learn, rather than teach, which goes against Brazil’s conservative educational structure. The object of this study is the concept map and the objective is to introduce seven concept map assessment models in order to make available evaluation instruments and/or constructs to teachers. This theoretical paper has three sections: (a meaningful learning and its contribution to concept maps; (b an analogy between mental and concept maps, and; (c concept map assessment models. There is no attempt to discuss which of the models are more efficient and appropriate to concept map evaluation as no empirical research of any sort was undertaken for testing.

  13. Solid-state retrodirective phased array concepts for microwave power transmission from Solar Power Satellite

    Science.gov (United States)

    Schroeder, K. G.; Petroff, I. K.

    1980-01-01

    Two prototype solid-state phased array systems concepts for potential use in the Solar Power Satellite are described. In both concepts, the beam is centered on the rectenna by means of phase conjugation of a pilot signal emanating from the ground. Also discussed is on-going solid-state amplifier development.

  14. Concept Evaluation for Hydraulic Yaw System

    DEFF Research Database (Denmark)

    Stubkier, Søren; Pedersen, Henrik C.; Andersen, Torben Ole

    2013-01-01

    a suspension system on a car, leading the loads away from the turbine structure. However, to realize a soft hydraulic yaw system a new design concept must be found. As a part of the development of the new concept a preliminary concept evaluation has been conducted, evaluating seven different hydraulic yaw...... concepts, ranging from a one-to-one copy of the electrical drive (electrical drives replaced by hydraulic dittos), to floating suspension systems mounted on hydraulic cylinders. Rough calculations of size and consequences of the different systems are presented ending up with the final concept for further...... investigation. Loads and yaw demands are based on the IEC 61400-1 standard for wind turbine design, and the loads for this examination are extrapolated from the HAWC2 aeroelastic design code. The concepts are based on a 5 MW off-shore turbine....

  15. Satellite power system (SPS) initial insurance evaluation

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-09-01

    The beginning of a process to educate the insurance industry about the Satellite Power System is reported. The report is divided into three sections. In the first section a general history describes how space risks are being insured today. This is followed by an attempt to identify the major risks inherent to the SPS. The final section presents a general projection of insurance market reactions to the Satellite Power System.

  16. Concept Evaluation for Hydraulic Yaw System

    DEFF Research Database (Denmark)

    Stubkier, Søren; Pedersen, Henrik C.; Andersen, Torben Ole

    2013-01-01

    a suspension system on a car, leading the loads away from the turbine structure. However, to realize a soft hydraulic yaw system a new design concept must be found. As a part of the development of the new concept a preliminary concept evaluation has been conducted, evaluating seven different hydraulic yaw......The yaw system is the subsystem on a wind turbine which ensures that the rotor plane of the turbine always is facing the wind direction. Studies from [1] show that a soft yaw system may be utilized to dampen the loads in the wind turbine structure. The soft yaw system operates much like...... investigation. Loads and yaw demands are based on the IEC 61400-1 standard for wind turbine design, and the loads for this examination are extrapolated from the HAWC2 aeroelastic design code. The concepts are based on a 5 MW off-shore turbine....

  17. Satellite power systems (SPS) concept definition study. Volume 7: SPS program plan and economic analysis, appendixes

    Science.gov (United States)

    Hanley, G.

    1978-01-01

    Three appendixes in support of Volume 7 are contained in this document. The three appendixes are: (1) Satellite Power System Work Breakdown Structure Dictionary; (2) SPS cost Estimating Relationships; and (3) Financial and Operational Concept. Other volumes of the final report that provide additional detail are: Executive Summary; SPS Systems Requirements; SPS Concept Evolution; SPS Point Design Definition; Transportation and Operations Analysis; and SPS Technology Requirements and Verification.

  18. A Synthetic Aperture System Based on Backscattering Signals of Compass Navigation Satellite: Concept and Feasibility

    Directory of Open Access Journals (Sweden)

    Wang Hai-yang

    2012-06-01

    Full Text Available A concept of a bi-static geosynchronous synthetic aperture system, which is formed by reusing backscattered signals of Compass Navigation Satellite System (CNSS, is proposed. The geometric relations of a geostationary satellite of CNSS, located on a geosynchronous satellite receiver, which is illuminated by the backscattered energy of a satellite of CNSS, and a ground station is built up, and following the relations as well as principle of synthetic aperture radar, we expatiate the feasibility of the system by considering parameters such as imaging resolution, ratio of signal to noise and link budget, etc.. Besides, the potential remote sensing applications for measurement of terrain humidity, characteristics of space-time dynamics of changing of terrain surface and atmospheric characteristic, etc..

  19. Simulation Studies of Satellite Laser CO2 Mission Concepts

    Science.gov (United States)

    Kawa, Stephan Randy; Mao, J.; Abshire, J. B.; Collatz, G. J.; Sun X.; Weaver, C. J.

    2011-01-01

    Results of mission simulation studies are presented for a laser-based atmospheric CO2 sounder. The simulations are based on real-time carbon cycle process modeling and data analysis. The mission concept corresponds to ASCENDS as recommended by the US National Academy of Sciences Decadal Survey. Compared to passive sensors, active (lidar) sensing of CO2 from space has several potentially significant advantages that hold promise to advance CO2 measurement capability in the next decade. Although the precision and accuracy requirements remain at unprecedented levels of stringency, analysis of possible instrument technology indicates that such sensors are more than feasible. Radiative transfer model calculations, an instrument model with representative errors, and a simple retrieval approach complete the cycle from "nature" run to "pseudodata" CO2. Several mission and instrument configuration options are examined, and the sensitivity to key design variables is shown. Examples are also shown of how the resulting pseudo-measurements might be used to address key carbon cycle science questions.

  20. gLISA: geosynchronous Laser Interferometer Space Antenna concepts with off-the-shelf satellites

    CERN Document Server

    Tinto, Massimo; Buchman, Sasha; Tilley, Scott

    2014-01-01

    We discuss two geosynchronous gravitational wave mission concepts, which we generically name gLISA. One relies on the science instrument hosting program onboard geostationary commercial satellites, while the other takes advantage of recent developments in the aerospace industry that result in dramatic satellite and launching vehicle cost reductions for a dedicated geosynchronous mission. To achieve the required level of disturbance free-fall onboard these large and heavy platforms we propose a "two-stage" drag-free system, which incorporates the Modular Gravitational Reference Sensor (MGRS) (developed at Stanford University) and does not rely on the use of micro-Newton thrusters. Although both mission concepts are characterized by different technical and programmatic challenges, individually they could be flown and operated at a cost significantly lower than those of previously envisioned gravitational wave missions. We estimate both mission concepts to cost less than 500M US$ each, and in the year 2015 we wi...

  1. The C3PO project: a laser communication system concept for small satellites

    Science.gov (United States)

    d'Humières, Benoît; Esmiller, Bruno; Gouy, Yann; Steck, Emilie; Quintana, Crisanto; Faulkner, Graham; O'Brien, Dominic; Sproll, Fabian; Wagner, Paul; Hampf, Daniel; Riede, Wolfgang; Salter, Michael; Wang, Qin; Platt, Duncan; Jakonis, Darius; Piao, Xiaoyu; Karlsson, Mikael; Oberg, Olof; Petermann, Ingemar; Michalkiewicz, Aneta; Krezel, Jerzy; Debowska, Anna; Thueux, Yoann

    2017-02-01

    The satellite market is shifting towards smaller (micro and nanosatellites), lowered mass and increased performance platforms. Nanosatellites and picosatellites have been used for a number of new, innovative and unique payloads and missions. This trend requires new concepts for a reduced size, a better performance/weight ratio and a reduction of onboard power consumption. In this context, disruptive technologies, such as laser-optical communication systems, are opening new possibilities. This paper presents the C3PO1 system, "advanced Concept for laser uplink/ downlink CommuniCation with sPace Objects", and the first results of the development of its key technologies. This project targets the design of a communications system that uses a ground-based laser to illuminate a satellite, and a Modulating Retro-Reflector (MRR) to return a beam of light modulated by data to the ground. This enables a downlink, without a laser source on the satellite. This architecture suits well to small satellite applications so as high data rates are potentially provided with very low board mass. C3PO project aims to achieve data rates of 1Gbit/s between LEO satellites and Earth with a communication payload mass of less than 1kilogram. In this paper, results of the initial experiments and demonstration of the key technologies will be shown.

  2. Mobile radio alternative systems study satellite/terrestrial (hybrid) systems concepts

    Science.gov (United States)

    Kiesling, J. D.; Anderson, R. E.

    1983-01-01

    The use of satellites for mobile radio service in non-urban areas of the United States in the years from 1985 to 2000 was investigated. Several satellite concepts are considered: a system with single-beam coverage of the fifty United States and Puerto Rico, and multi-beam satellites with greater capacity. All of the needed functions and services identified in the market study are provided by the satellite systems, including nationwide radio access to vehicles without knowledge of vehicle location wideband data transmission from remote sites, two way exchange of short data and control messages between vehicles and dispatch or control centers, and automatic vehicle location (surveillance). The costs of providing the services are within acceptable limits, and the desired returns to the system investors are attractive. The criteria by which the Federal Communication judges the competing demands for public radio spectrum are reviewed with comments on how the criteria might apply to the consideration of land mobile satellites. Institutional arrangements for operating a mobile satellite system are based on the present institutional arrangements in which the services are offered to the end users through wireline and radio common carriers, with direct access by large private and government users.

  3. A system for the simulation and evaluation of satellite communication networks

    Science.gov (United States)

    Bagwell, J. W.

    1984-01-01

    With the emergence of a new era in satellite communications, brought about by NASA's thrust into the Ka band with multibeam and onboard processing technologies, new and innovative techniques for evaluating these concepts and systems are required. To this end, NASA, in conjunction with its extensive program for advanced communications technology development, has undertaken to develop a concept for the simulation and evaluation of a complete communications network. Incorporated in this network will be proof-of-concept models of the latest technologies proposed for future satellite communications systems. These include low noise receivers, matrix switches, baseband processors, and solid state and tube type high power amplifiers. To accomplish this, numerous supporting technologies must be added to those aforementioned proof-of-concept models. These include controllers for synchronization, order wire, resource allocation, gain compensation, signal leveling, power augmentation, and rain fade and range delay simulation. Taken together, these will be assembled to comprise a system capable of addressing numerous design and performance questions. The simulation and evaluation system, as planned, will be modular in design and implementation, capable of modification and updating to track and evaluate a continuum of emerging concepts and technologies. Previously announced in STAR as N84-13400

  4. A Comparison Of A Solar Power Satellite Concept To A Concentrating Solar Power System

    Science.gov (United States)

    Smitherman, David V.

    2013-01-01

    A comparison is made of a Solar Power Satellite concept in geostationary Earth orbit to a Concentrating Solar Power system on the ground to analyze overall efficiencies of each infrastructure from solar radiance at 1 AU to conversion and transmission of electrical energy into the power grid on the Earth's surface. Each system is sized for a 1-gigawatt output to the power grid and then further analyzed to determine primary collector infrastructure areas. Findings indicate that even though the Solar Power Satellite concept has a higher end-to-end efficiency, that the combined space and ground collector infrastructure is still about the same size as a comparable Concentrating Solar Power system on the ground.

  5. FACET: Future ATM Concepts Evaluation Tool

    Science.gov (United States)

    Bilmoria, Karl D.; Banavar, Sridhar; Chatterji, Gano B.; Sheth, Kapil S.; Grabbe, Shon

    2000-01-01

    FACET (Future ATM Concepts Evaluation Tool) is an Air Traffic Management research tool being developed at the NASA Ames Research Center. This paper describes the design, architecture and functionalities of FACET. The purpose of FACET is to provide E simulation environment for exploration, development and evaluation of advanced ATM concepts. Examples of these concepts include new ATM paradigms such as Distributed Air-Ground Traffic Management, airspace redesign and new Decision Support Tools (DSTs) for controllers working within the operational procedures of the existing air traffic control system. FACET is currently capable of modeling system-wide en route airspace operations over the contiguous United States. Airspace models (e.g., Center/sector boundaries, airways, locations of navigation aids and airports) are available from databases. A core capability of FACET is the modeling of aircraft trajectories. Using round-earth kinematic equations, aircraft can be flown along flight plan routes or great circle routes as they climb, cruise and descend according to their individual aircraft-type performance models. Performance parameters (e.g., climb/descent rates and speeds, cruise speeds) are obtained from data table lookups. Heading, airspeed and altitude-rate dynamics are also modeled. Additional functionalities will be added as necessary for specific applications. FACET software is written in Java and C programming languages. It is platform-independent, and can be run on a variety of computers. FACET has been designed with a modular software architecture to enable rapid integration of research prototype implementations of new ATM concepts. There are several advanced ATM concepts that are currently being implemented in FACET airborne separation assurance, dynamic density predictions, airspace redesign (re-sectorization), benefits of a controller DST for direct-routing, and the integration of commercial space transportation system operations into the U.S. National

  6. FACET: Future ATM Concepts Evaluation Tool

    Science.gov (United States)

    Bilmoria, Karl D.; Banavar, Sridhar; Chatterji, Gano B.; Sheth, Kapil S.; Grabbe, Shon

    2000-01-01

    FACET (Future ATM Concepts Evaluation Tool) is an Air Traffic Management research tool being developed at the NASA Ames Research Center. This paper describes the design, architecture and functionalities of FACET. The purpose of FACET is to provide E simulation environment for exploration, development and evaluation of advanced ATM concepts. Examples of these concepts include new ATM paradigms such as Distributed Air-Ground Traffic Management, airspace redesign and new Decision Support Tools (DSTs) for controllers working within the operational procedures of the existing air traffic control system. FACET is currently capable of modeling system-wide en route airspace operations over the contiguous United States. Airspace models (e.g., Center/sector boundaries, airways, locations of navigation aids and airports) are available from databases. A core capability of FACET is the modeling of aircraft trajectories. Using round-earth kinematic equations, aircraft can be flown along flight plan routes or great circle routes as they climb, cruise and descend according to their individual aircraft-type performance models. Performance parameters (e.g., climb/descent rates and speeds, cruise speeds) are obtained from data table lookups. Heading, airspeed and altitude-rate dynamics are also modeled. Additional functionalities will be added as necessary for specific applications. FACET software is written in Java and C programming languages. It is platform-independent, and can be run on a variety of computers. FACET has been designed with a modular software architecture to enable rapid integration of research prototype implementations of new ATM concepts. There are several advanced ATM concepts that are currently being implemented in FACET airborne separation assurance, dynamic density predictions, airspace redesign (re-sectorization), benefits of a controller DST for direct-routing, and the integration of commercial space transportation system operations into the U.S. National

  7. Evaluation on Radiometric Capability of Chinese Optical Satellite Sensors

    Science.gov (United States)

    Yang, Aixia; Zhong, Bo; Wu, Shanlong; Liu, Qinhuo

    2017-01-01

    The radiometric capability of on-orbit sensors should be updated on time due to changes induced by space environmental factors and instrument aging. Some sensors, such as Moderate Resolution Imaging Spectroradiometer (MODIS), have onboard calibrators, which enable real-time calibration. However, most Chinese remote sensing satellite sensors lack onboard calibrators. Their radiometric calibrations have been updated once a year based on a vicarious calibration procedure, which has affected the applications of the data. Therefore, a full evaluation of the sensors’ radiometric capabilities is essential before quantitative applications can be made. In this study, a comprehensive procedure for evaluating the radiometric capability of several Chinese optical satellite sensors is proposed. In this procedure, long-term radiometric stability and radiometric accuracy are the two major indicators for radiometric evaluation. The radiometric temporal stability is analyzed by the tendency of long-term top-of-atmosphere (TOA) reflectance variation; the radiometric accuracy is determined by comparison with the TOA reflectance from MODIS after spectrally matching. Three Chinese sensors including the Charge-Coupled Device (CCD) camera onboard Huan Jing 1 satellite (HJ-1), as well as the Visible and Infrared Radiometer (VIRR) and Medium-Resolution Spectral Imager (MERSI) onboard the Feng Yun 3 satellite (FY-3) are evaluated in reflective bands based on this procedure. The results are reasonable, and thus can provide reliable reference for the sensors’ application, and as such will promote the development of Chinese satellite data. PMID:28117745

  8. An allotment planning concept and related computer software for planning the fixed satellite service at the 1988 space WARC

    Science.gov (United States)

    Miller, Edward F.; Heyward, Ann O.; Ponchak, Denise S.; Spence, Rodney L.; Whyte, Wayne A., Jr.; Zuzek, John E.

    1987-01-01

    Described is a two-phase approach to allotment planning suitable for use in establishing the fixed satellite service at the 1988 Space World Administrative Radio Conference (ORB-88). The two phases are (1) the identification of predetermined geostationary arc segments common togroups of administrations, and (2) the use of a synthesis program to identify example scenarios of space station placements. The planning approach is described in detail and is related to the objectives of the confernece. Computer software has been developed to implement the concepts, and a complete discussion on the logic and rationale for identifying predetermined arc segments is given. Example scenarios are evaluated to give guidance in the selection of the technical characteristics of space communications systems to be planned. The allotment planning concept described guarantees in practice equitable access to the geostationary orbit, provides flexibility in implementation, and reduces the need for coordination among administrations.

  9. Educational Videogames: Concept, Design And Evaluation

    Science.gov (United States)

    Rohrlick, D.; Yang, A.; Kilb, D. L.; Ma, L.; Ruzic, R.; Peach, C. L.; Layman, C. C.

    2013-12-01

    Videogames have historically gained popularity thanks to their entertainment rather than their educational value. This may be due, in part, to the fact that many educational videogames present academic concepts in dry, quiz-like ways, without the visual experiences, interactivity, and excitement of non-educational games. The increasing availability of tools that allow designers to easily create rich experiences for players now makes it simpler than ever for educational game designers to generate the visual experiences, interactivity, and excitement that gamers have grown to expect. Based on data from our work, when designed effectively, educational games can engage players, teach concepts, and tear down the stereotype of the stuffy, boring educational game. Our team has been experimenting with different ways to present scientific and mathematical concepts to middle and high school students through engaging, interactive games. When designing a gameplay concept, we focus on what we want the player to learn and experience as well as how to maintain a learning environment that is fun and engaging. Techniques that we have found successful include the use of a series of fast-paced 'minigames,' and the use of a 'simulator' learning method that allows a player to learn by completing objectives similar to those completed by today's scientists. Formative evaluations of our games over the past year have revealed both design strengths and weaknesses. Based on findings from a systematic evaluation of game play with diverse groups, with data collected through in-person observations of game play, knowledge assessments, focus groups, interviews with players, and computer tracking of students' game play behavior, we have found that players are uniformly enthusiastic about the educational tools. At the same time, we find there is more work to be done to make our tools fully intuitive, and to effectively present complex mathematical and scientific concepts to learners from a wide

  10. Coherent Evaluation of Aerosol Data Products from Multiple Satellite Sensors

    Science.gov (United States)

    Ichoku, Charles

    2011-01-01

    Aerosol retrieval from satellite has practically become routine, especially during the last decade. However, there is often disagreement between similar aerosol parameters retrieved from different sensors, thereby leaving users confused as to which sensors to trust for answering important science questions about the distribution, properties, and impacts of aerosols. As long as there is no consensus, and the inconsistencies are not well characterized and understood, there will be no way of developing reliable model inputs and climate data records from satellite aerosol measurements. Fortunately, the Aerosol Robotic Network (AERONET) is providing well-calibrated globally representative ground-based aerosol measurements corresponding to the satellite-retrieved products. Through a recently developed web-based Multi-sensor Aerosol Products Sampling System (MAPSS), we are utilizing the advantages offered by collocated AERONET and satellite products to characterize and evaluate aerosol retrieval from multiple sensors. Indeed, MAPSS and its companion statistical tool AeroStat are facilitating detailed comparative uncertainty analysis of satellite aerosol measurements from Terra-MODIS, Aqua-MODIS, Terra-MISR, Aura-OMI, Parasol-POLDER, and Calipso-CALIOP. In this presentation, we will describe the strategy of the MAPSS system, its potential advantages for the aerosol community, and the preliminary results of an integrated comparative uncertainly analysis of aerosol products from multiple satellite sensors.

  11. Advanced payload concepts and system architecture for emerging services in Indian National Satellite Systems

    Science.gov (United States)

    Balasubramanian, E. P.; Rao, N. Prahlad; Sarkar, S.; Singh, D. K.

    2008-07-01

    Over the past two decades Indian Space Research Organization (ISRO) has developed and operationalized satellites to generate a large capacity of transponders for telecommunication service use in INSAT system. More powerful on-board transmitters are built to usher-in direct-to-home broadcast services. These have transformed the Satcom application scenario in the country. With the proliferation of satellite technology, a shift in the Indian market is witnessed today in terms of demand for new services like Broadband Internet, Interactive Multimedia, etc. While it is imperative to pay attention to market trends, ISRO is also committed towards taking the benefits of technological advancement to all round growth of our population, 70% of which dwell in rural areas. The initiatives already taken in space application related to telemedicine, tele-education and Village Resource Centres are required to be taken to a greater height of efficiency. These targets pose technological challenges to build a large capacity and cost-effective satellite system. This paper addresses advanced payload concepts and system architecture along with the trade-off analysis on design parameters in proposing a new generation satellite system capable of extending the reach of the Indian broadband structure to individual users, educational and medical institutions and enterprises for interactive services. This will be a strategic step in the evolution of INSAT system to employ advanced technology to touch every human face of our population.

  12. Design Concepts for a Small Space-Based GEO Relay Satellite for Missions Between Low Earth and near Earth Orbits

    Science.gov (United States)

    Bhasin, Kul B.; Warner, Joseph D.; Oleson, Steven; Schier, James

    2014-01-01

    The main purpose of the Small Space-Based Geosynchronous Earth orbiting (GEO) satellite is to provide a space link to the user mission spacecraft for relaying data through ground networks to user Mission Control Centers. The Small Space Based Satellite (SSBS) will provide services comparable to those of a NASA Tracking Data Relay Satellite (TDRS) for the same type of links. The SSBS services will keep the user burden the same or lower than for TDRS and will support the same or higher data rates than those currently supported by TDRS. At present, TDRSS provides links and coverage below GEO; however, SSBS links and coverage capability to above GEO missions are being considered for the future, especially for Human Space Flight Missions (HSF). There is also a rising need for the capability to support high data rate links (exceeding 1 Gbps) for imaging applications. The communication payload on the SSBS will provide S/Ka-band single access links to the mission and a Ku-band link to the ground, with an optical communication payload as an option. To design the communication payload, various link budgets were analyzed and many possible operational scenarios examined. To reduce user burden, using a larger-sized antenna than is currently in use by TDRS was considered. Because of the SSBS design size, it was found that a SpaceX Falcon 9 rocket could deliver three SSBSs to GEO. This will greatly reduce the launch costs per satellite. Using electric propulsion was also evaluated versus using chemical propulsion; the power system size and time to orbit for various power systems were also considered. This paper will describe how the SSBS will meet future service requirements, concept of operations, and the design to meet NASA users' needs for below and above GEO missions. These users' needs not only address the observational mission requirements but also possible HSF missions to the year 2030. We will provide the trade-off analysis of the communication payload design in terms of

  13. Evaluation of the DeepWind concept

    DEFF Research Database (Denmark)

    Schmidt Paulsen, Uwe; Borg, Michael; Gonzales Seabra, Luis Alberto

    , as well as the technical and scientific recommendations are performed. The work is a result of the contributions within the DeepWind project which is supported by the European Commission, Grant 256769 FP7 Energy 2010 - Future emerging technologies, and by the DeepWind beneficiaries: DTU(DK), AAU......The report describes the DeepWind 5 MW conceptual design as a baseline for results obtained in the scientific and technical work packages of the DeepWind project. A comparison of DeepWi nd with existing VAWTs and paper projects are carried out and the evaluation of the concept in terms of cost......(DK), TUDELFT(NL), TUTRENTO(I), DHI(DK), SINTEF(N), MARINTEK(N), MARIN(NL), NREL(USA), STATOIL(N), VESTAS(D K) and NENUPHAR(F)....

  14. Evaluating large scale orthophotos derived from high resolution satellite imagery

    Science.gov (United States)

    Ioannou, Maria Teresa; Georgopoulos, Andreas

    2013-08-01

    For the purposes of a research project, for the compilation of the archaeological and environmental digital map of the island of Antiparos, the production of updated large scale orthophotos was required. Hence suitable stereoscopic high resolution satellite imagery was acquired. Two Geoeye-1 stereopairs were enough to cover this small island of the Cyclades complex in the central Aegean. For the orientation of the two stereopairs numerous ground control points were determined using GPS observations. Some of them would also serve as check points. The images were processed using commercial stereophotogrammetric software suitable to process satellite stereoscopic imagery. The results of the orientations are evaluated and the digital terrain model was produced using automated and manual procedures. The DTM was checked both internally and externally with comparison to other available DTMs. In this paper the procedures for producing the desired orthophotography are critically presented and the final result is compared and evaluated for its accuracy, completeness and efficiency. The final product is also compared against the orthophotography produced by Ktimatologio S.A. using aerial images in 2007. The orthophotography produced has been evaluated metrically using the available check points, while qualitative evaluation has also been performed. The results are presented and a critical approach for the usability of satellite imagery for the production of large scale orthophotos is attempted.

  15. Accuracy Performance Evaluation of Beidou Navigation Satellite System

    Science.gov (United States)

    Wang, W.; Hu, Y. N.

    2017-03-01

    Accuracy is one of the key elements of the regional Beidou Navigation Satellite System (BDS) performance standard. In this paper, we review the definition specification and evaluation standard of the BDS accuracy. Current accuracy of the regional BDS is analyzed through the ground measurements and compared with GPS in terms of dilution of precision (DOP), signal-in-space user range error (SIS URE), and positioning accuracy. The Positioning DOP (PDOP) map of BDS around Chinese mainland is compared with that of GPS. The GPS PDOP is between 1.0-2.0 and does not vary with the user latitude and longitude, while the BDS PDOP varies between 1.5-5.0, and increases as the user latitude increases, and as the user longitude apart from 118°. The accuracies of the broadcast orbits of BDS are assessed by taking the precise orbits from International GNSS Service (IGS) as the reference, and by making satellite laser ranging (SLR) residuals. The radial errors of the BDS inclined geosynchronous orbit (IGSO) and medium orbit (MEO) satellites broadcast orbits are at the 0.5m level, which are larger than those of GPS satellites at the 0.2m level. The SLR residuals of geosynchronous orbit (GEO) satellites are 65.0cm, which are larger than those of IGSO, and MEO satellites, at the 50.0cm level. The accuracy of broadcast clock offset parameters of BDS is computed by taking the clock measurements of Two-way Satellite Radio Time Frequency Transfer as the reference. Affected by the age of broadcast clock parameters, the error of the broadcast clock offset parameters of the MEO satellites is the largest, at the 0.80m level. Finally, measurements of the multi-GNSS (MGEX) receivers are used for positioning accuracy assessment of BDS and GPS. It is concluded that the positioning accuracy of regional BDS is better than 10m at the horizontal component and the vertical component. The combined positioning accuracy of both systems is better than one specific system.

  16. Evaluation of CDMA system capacity for mobile satellite system applications

    Science.gov (United States)

    Smith, Partrick O.; Geraniotis, Evaggelos A.

    1988-01-01

    A specific Direct-Sequence/Pseudo-Noise (DS/PN) Code-Division Multiple-Access (CDMA) mobile satellite system (MSAT) architecture is discussed. The performance of this system is evaluated in terms of the maximum number of active MSAT subscribers that can be supported at a given uncoded bit-error probability. The evaluation decouples the analysis of the multiple-access capability (i.e., the number of instantaneous user signals) from the analysis of the multiple-access mutliplier effect allowed by the use of CDMA with burst-modem operation. We combine the results of these two analyses and present numerical results for scenarios of interest to the mobile satellite system community.

  17. Efficient Satellite Scheduling Based on Improved Vector Evaluated Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Tengyue Mao

    2012-03-01

    Full Text Available Satellite scheduling is a typical multi-peak, many-valley, nonlinear multi-objective optimization problem. How to effectively implement the satellite scheduling is a crucial research in space areas.This paper mainly discusses the performance of VEGA (Vector Evaluated Genetic Algorithm based on the study of basic principles of VEGA algorithm, algorithm realization and test function, and then improves VEGA algorithm through introducing vector coding, new crossover and mutation operators, new methods to assign fitness and hold good individuals. As a result, the diversity and convergence of improved VEGA algorithm of improved VEGA algorithm have been significantly enhanced and will be applied to Earth-Mars orbit optimization. At the same time, this paper analyzes the results of the improved VEGA, whose results of performance analysis and evaluation show that although VEGA has a profound impact upon multi-objective evolutionary research,  multi-objective evolutionary algorithm on the basis of Pareto seems to be a more effective method to get the non-dominated solutions from the perspective of diversity and convergence of experimental result. Finally, based on Visual C + + integrated development environment, we have implemented improved vector evaluation algorithm in the satellite scheduling.

  18. Improved Traceability of a Small Satellite Mission Concept to Requirements Using Model Based System Engineering

    Science.gov (United States)

    Reil, Robin L.

    2014-01-01

    Model Based Systems Engineering (MBSE) has recently been gaining significant support as a means to improve the "traditional" document-based systems engineering (DBSE) approach to engineering complex systems. In the spacecraft design domain, there are many perceived and propose benefits of an MBSE approach, but little analysis has been presented to determine the tangible benefits of such an approach (e.g. time and cost saved, increased product quality). This paper presents direct examples of how developing a small satellite system model can improve traceability of the mission concept to its requirements. A comparison of the processes and approaches for MBSE and DBSE is made using the NASA Ames Research Center SporeSat CubeSat mission as a case study. A model of the SporeSat mission is built using the Systems Modeling Language standard and No Magic's MagicDraw modeling tool. The model incorporates mission concept and requirement information from the mission's original DBSE design efforts. Active dependency relationships are modeled to demonstrate the completeness and consistency of the requirements to the mission concept. Anecdotal information and process-duration metrics are presented for both the MBSE and original DBSE design efforts of SporeSat.

  19. Evaluation of CHAMP Satellite Orbit with SLR Measurements

    Institute of Scientific and Technical Information of China (English)

    QIN Xianping; YANG Yuanxi

    2005-01-01

    The technique of Evaluating CHAMP satellite orbit with SLR measurements is presented. As an independent evaluation of the orbit solution, SLR data observed from January 1 to 16, 2002 are processed to compute the residuals after fixing the GFZ's post science orbits solutions. The SLR residuals are computed as the differences of the SLR measurements minus the corresponding distances between the SLR station and the GPS-derived orbit positions. On the basis of the SLR residuals analysis, it is found that the accuracy of GFZ's post science orbits is better than 10 em and that there is no systematic error in GFZ's post science orbits.

  20. Novel evaluation method of TCP performance over satellite links

    Institute of Scientific and Technical Information of China (English)

    Wang Lina; Gu Xuemai

    2006-01-01

    A novel and efficient method to evaluate the transmission control protocol (TCP) performance over satellite links is presented. A TCP module is divided into three functional blocks, namely data processing, congestion control and error control. The re-established TCP module is easy to update TCP congestion control strategy or error control strategy. With the proposed analysis approach, the interactions between different congestion control and error control mechanisms, as well as the performance of various combination protocols in satellite environments have been investigated. Simulation results obtained through a series of experiments have shown that SNACK-based error control strategy can perform well with any other congestion control strategy. The best performance can be achieved by TCP New Reno congestion control strategy and SNACK-based error control strategy.

  1. Using ARM Data to Evaluate Satellite Surface Solar Flux Retrievals

    Energy Technology Data Exchange (ETDEWEB)

    Hinkelman, L.M.; Stackhouse, P.W.; Young, D.F.; Long, C.N.; Rutan, D.

    2005-03-18

    The accurate, long-term radiometric data collected by Atmospheric Radiation Measurement (ARM) has become essential to the evaluation of surface radiation budget data from satellites. Since the spatial and temporal characteristics of data from these two sources are very different, the comparisons are typically made for long-term average values. While such studies provide a general indication of the quality of satellite flux products, more detailed analysis is required to understand specific retrieval algorithm weaknesses. Here we show how data from the ARM shortwave flux analysis (SFA) value added product (VAP) are being used to assess solar fluxes in the Global Energy and Water Cycle Experiment (GEWEX) Surface Radiation Budget (SRB), release 2.5.

  2. Thermal design, analysis and comparison on three concepts of space solar power satellite

    Science.gov (United States)

    Yang, Chen; Hou, Xinbin; Wang, Li

    2017-08-01

    Space solar power satellites (SSPS) have been widely studied as systems for collecting solar energy in space and transmitting it wirelessly to earth. A previously designed planar SSPS concept collects solar power in two huge arrays and then transmits it through one side of the power-conduction joint to the antenna. However, the system's one group of power-conduction joints may induce a single point of failure. As an SSPS concept, the module symmetrical concentrator (MSC) architecture has many advantages. This architecture can help avoid the need for a large, potentially failure-prone conductive rotating joint and limit wiring mass. However, the thermal control system has severely restricted the rapid development of MSC, especially in the sandwich module. Because of the synchronous existence of five suns concentration and solar external heat flux, the sandwich module will have a very high temperature, which will surpass the permissible temperature of the solar cells. Recently, an alternate multi-rotary joints (MR) SSPS concept was designed by the China Academy of Space Technology (CAST). This system has multiple joints to avoid the problem of a single point of failure. Meanwhile, this concept has another advantage for reducing the high power and heat removal in joints. It is well known to us that, because of the huge external flux in SSPS, the thermal management sub-system is an important component that cannot be neglected. Based on the three SSPS concepts, this study investigated the thermal design and analysis of a 1-km, gigawatt-level transmitting antenna in SSPS. This study compares the thermal management sub-systems of power-conduction joints in planar and MR SSPS. Moreover, the study considers three classic thermal control architectures of the MSC's sandwich module: tile, step, and separation. The study also presents an elaborate parameter design, analysis and discussion of step architecture. Finally, the results show the thermal characteristics of each SSPS

  3. Evaluation of Aerosol Properties in GCMs using Satellite Measurements

    Science.gov (United States)

    Wang, Y.; Jiang, J. H.; Su, H.; Zhang, H.

    2015-12-01

    Atmospheric aerosols from natural or anthropogenic sources have profound impacts on the regional and global climate. Currently the radiative forcing of aerosols predicted by global climate models remains highly uncertain, representing the largest uncertainty in climate predictions. The uncertainty mainly arises from the complicated aerosol chemical and physical properties, coarse emission inventories for pre-cursor gases as well as unrealistic representations of aerosol activation and cloud processing in global climate models. In this study, we will utilize multiple satellite measurements including MODIS, MISR and CALIPSO to quantitatively evaluate aerosol simulations from climate models. Our analyses show that the global means in AOD climatology from NCAR CAM5 and GFDL AM3 simulations are comparable with satellite measurements. However, the overall correlation coefficient between the AOD spatial patterns from CAM5 and satellite is only 0.4. Moreover, at finer scales, the magnitude of AOD in CAM5 is much lower than satellite measurements for most of the non-dust regions, especially over East Asia. GFDL AM3 shows better AOD simulations over East Asia. The underestimated AOD over remote maritime areas in CAM5 was attributed to the unrealistic wet removal processes in convective clouds of CAM5. Over continents, biases on AOD could stem from underestimations in the emissions inventory and unresolved sub-grid variations of relative humidity due to the model's coarse resolution. Uncertainty from emission inventory over developing countries in East Asia will be assessed using the newly updated Regional Emission inventory in Asia (REAS) and Multi-resolution Emission Inventory in China (MEIC) in the model simulations.

  4. Spatial evaluation of volcanic ash forecasts using satellite observations

    Science.gov (United States)

    Harvey, N. J.; Dacre, H. F.

    2016-01-01

    The decision to close airspace in the event of a volcanic eruption is based on hazard maps of predicted ash extent. These are produced using output from volcanic ash transport and dispersion (VATD) models. In this paper the fractions skill score has been used for the first time to evaluate the spatial accuracy of VATD simulations relative to satellite retrievals of volcanic ash. This objective measure of skill provides more information than traditional point-by-point metrics, such as success index and Pearson correlation coefficient, as it takes into the account spatial scale over which skill is being assessed. The FSS determines the scale over which a simulation has skill and can differentiate between a "near miss" and a forecast that is badly misplaced. The idealized scenarios presented show that even simulations with considerable displacement errors have useful skill when evaluated over neighbourhood scales of 200-700 (km)2. This method could be used to compare forecasts produced by different VATDs or using different model parameters, assess the impact of assimilating satellite-retrieved ash data and evaluate VATD forecasts over a long time period.

  5. Spatial evaluation of volcanic ash forecasts using satellite observations

    Directory of Open Access Journals (Sweden)

    N. J. Harvey

    2015-09-01

    Full Text Available The decision to close airspace in the event of a volcanic eruption is based on hazard maps of predicted ash extent. These are produced using output from volcanic ash transport and dispersion (VATD models. In this paper an objective metric to evaluate the spatial accuracy of VATD simulations relative to satellite retrievals of volcanic ash is presented. The metric is based on the fractions skill score (FSS. This measure of skill provides more information than traditional point-by-point metrics, such as success index and Pearson correlation coefficient, as it takes into the account spatial scale over which skill is being assessed. The FSS determines the scale over which a simulation has skill and can differentiate between a "near miss" and a forecast that is badly misplaced. The idealised scenarios presented show that even simulations with considerable displacement errors have useful skill when evaluated over neighbourhood scales of 200–700 km2. This method could be used to compare forecasts produced by different VATDs or using different model parameters, assess the impact of assimilating satellite retrieved ash data and evaluate VATD forecasts over a long time period.

  6. Performance Evaluation of Data Compression Systems Applied to Satellite Imagery

    Directory of Open Access Journals (Sweden)

    Lilian N. Faria

    2012-01-01

    Full Text Available Onboard image compression systems reduce the data storage and downlink bandwidth requirements in space missions. This paper presents an overview and evaluation of some compression algorithms suitable for remote sensing applications. Prediction-based compression systems, such as DPCM and JPEG-LS, and transform-based compression systems, such as CCSDS-IDC and JPEG-XR, were tested over twenty multispectral (5-band images from CCD optical sensor of the CBERS-2B satellite. Performance evaluation of these algorithms was conducted using both quantitative rate-distortion measurements and subjective image quality analysis. The PSNR, MSSIM, and compression ratio results plotted in charts and the SSIM maps are used for comparison of quantitative performance. Broadly speaking, the lossless JPEG-LS outperforms other lossless compression schemes, and, for lossy compression, JPEG-XR can provide lower bit rate and better tradeoff between compression ratio and image quality.

  7. An Integrated Decision Making Model for Evaluation of Concept Design

    Directory of Open Access Journals (Sweden)

    G. Green

    2004-01-01

    Full Text Available The Conceptual design phase generates various design concepts and these are then evaluated in order to identify the 'Best’ concept. Identifying the Best concept is important because much of the product life cycle cost is decided in this phase. Various evaluation techniques are performed so as to aid decision-making. Different criteria are weighted against concepts for the comparison. This paper describes the research being carried out at the University of Glasgow on design evaluation. It presents the Application of fuzzy logic for design evaluation and proposes an integrated decision-making model for design evaluation. This is a part of research project that aims at developing a computer tool for evaluation process to aid decision-making.

  8. Concept design of HAYATE : Small satellite for supporting Antarctic geophysical observation

    OpenAIRE

    Yoshihara, Keisuke; Sugiura, Yoshiki; Sekiguchi,Masato; Ui, Kyoichi; Tsurumi,Singo; Nakaya, Koji; Mori, Makoto; Matsunaga, Saburo; Ohkami, Yoshiaki

    1999-01-01

    This paper presents the results of conceptual design of a small communication satellite (HAYATE) for supporting research in Antarctica and remote islands. The HAY ATE satellite collects environmental data from unmanned probes located on the Antarctic ice plate and also transmits data from Syowa Station in Antarctica to Japan and the United States. Through the satellite mission analyses, we confirmed that the HAYATE satellite would be able to gather data for GPS baseline analysis and to observ...

  9. A Satellite-Based Imaging Instrumentation Concept for Hyperspectral Thermal Remote Sensing

    Directory of Open Access Journals (Sweden)

    Thomas Udelhoven

    2017-07-01

    Full Text Available This paper describes the concept of the hyperspectral Earth-observing thermal infrared (TIR satellite mission HiTeSEM (High-resolution Temperature and Spectral Emissivity Mapping. The scientific goal is to measure specific key variables from the biosphere, hydrosphere, pedosphere, and geosphere related to two global problems of significant societal relevance: food security and human health. The key variables comprise land and sea surface radiation temperature and emissivity, surface moisture, thermal inertia, evapotranspiration, soil minerals and grain size components, soil organic carbon, plant physiological variables, and heat fluxes. The retrieval of this information requires a TIR imaging system with adequate spatial and spectral resolutions and with day-night following observation capability. Another challenge is the monitoring of temporally high dynamic features like energy fluxes, which require adequate revisit time. The suggested solution is a sensor pointing concept to allow high revisit times for selected target regions (1–5 days at off-nadir. At the same time, global observations in the nadir direction are guaranteed with a lower temporal repeat cycle (>1 month. To account for the demand of a high spatial resolution for complex targets, it is suggested to combine in one optic (1 a hyperspectral TIR system with ~75 bands at 7.2–12.5 µm (instrument NEDT 0.05 K–0.1 K and a ground sampling distance (GSD of 60 m, and (2 a panchromatic high-resolution TIR-imager with two channels (8.0–10.25 µm and 10.25–12.5 µm and a GSD of 20 m. The identified science case requires a good correlation of the instrument orbit with Sentinel-2 (maximum delay of 1–3 days to combine data from the visible and near infrared (VNIR, the shortwave infrared (SWIR and TIR spectral regions and to refine parameter retrieval.

  10. A Satellite-Based Imaging Instrumentation Concept for Hyperspectral Thermal Remote Sensing.

    Science.gov (United States)

    Udelhoven, Thomas; Schlerf, Martin; Segl, Karl; Mallick, Kaniska; Bossung, Christian; Retzlaff, Rebecca; Rock, Gilles; Fischer, Peter; Müller, Andreas; Storch, Tobias; Eisele, Andreas; Weise, Dennis; Hupfer, Werner; Knigge, Thiemo

    2017-07-01

    This paper describes the concept of the hyperspectral Earth-observing thermal infrared (TIR) satellite mission HiTeSEM (High-resolution Temperature and Spectral Emissivity Mapping). The scientific goal is to measure specific key variables from the biosphere, hydrosphere, pedosphere, and geosphere related to two global problems of significant societal relevance: food security and human health. The key variables comprise land and sea surface radiation temperature and emissivity, surface moisture, thermal inertia, evapotranspiration, soil minerals and grain size components, soil organic carbon, plant physiological variables, and heat fluxes. The retrieval of this information requires a TIR imaging system with adequate spatial and spectral resolutions and with day-night following observation capability. Another challenge is the monitoring of temporally high dynamic features like energy fluxes, which require adequate revisit time. The suggested solution is a sensor pointing concept to allow high revisit times for selected target regions (1-5 days at off-nadir). At the same time, global observations in the nadir direction are guaranteed with a lower temporal repeat cycle (>1 month). To account for the demand of a high spatial resolution for complex targets, it is suggested to combine in one optic (1) a hyperspectral TIR system with ~75 bands at 7.2-12.5 µm (instrument NEDT 0.05 K-0.1 K) and a ground sampling distance (GSD) of 60 m, and (2) a panchromatic high-resolution TIR-imager with two channels (8.0-10.25 µm and 10.25-12.5 µm) and a GSD of 20 m. The identified science case requires a good correlation of the instrument orbit with Sentinel-2 (maximum delay of 1-3 days) to combine data from the visible and near infrared (VNIR), the shortwave infrared (SWIR) and TIR spectral regions and to refine parameter retrieval.

  11. Concept maps: a strategy to teach and evaluate critical thinking.

    Science.gov (United States)

    Daley, B J; Shaw, C R; Balistrieri, T; Glasenapp, K; Piacentine, L

    1999-01-01

    The purpose of this article is to describe a study that implemented concept maps as a methodology to teach and evaluate critical thinking. Students in six senior clinical groups were taught to use concept maps. Students created three concept maps over the course of the semester. Data analysis demonstrated a group mean score of 40.38 on the first concept map and 135.55 on the final concept map, for a difference of 98.16. The paired t value comparing the first concept map to the final concept map was -5.69. The data indicated a statistically significant difference between the first and final maps. This difference is indicative of the students' increase in conceptual and critical thinking.

  12. Evaluation of voice codecs for the Australian mobile satellite system

    Science.gov (United States)

    Bundrock, Tony; Wilkinson, Mal

    1990-01-01

    The evaluation procedure to choose a low bit rate voice coding algorithm is described for the Australian land mobile satellite system. The procedure is designed to assess both the inherent quality of the codec under 'normal' conditions and its robustness under 'severe' conditions. For the assessment, normal conditions were chosen to be random bit error rate with added background acoustic noise and the severe condition is designed to represent burst error conditions when mobile satellite channel suffers from signal fading due to roadside vegetation. The assessment is divided into two phases. First, a reduced set of conditions is used to determine a short list of candidate codecs for more extensive testing in the second phase. The first phase conditions include quality and robustness and codecs are ranked with a 60:40 weighting on the two. Second, the short listed codecs are assessed over a range of input voice levels, BERs, background noise conditions, and burst error distributions. Assessment is by subjective rating on a five level opinion scale and all results are then used to derive a weighted Mean Opinion Score using appropriate weights for each of the test conditions.

  13. An evaluation of the concept of innateness.

    Science.gov (United States)

    Mameli, Matteo; Bateson, Patrick

    2011-02-12

    The concept of innateness is often used in explanations and classifications of biological and cognitive traits. But does this concept have a legitimate role to play in contemporary scientific discourse? Empirical studies and theoretical developments have revealed that simple and intuitively appealing ways of classifying traits (e.g. genetically specified versus owing to the environment) are inadequate. They have also revealed a variety of scientifically interesting ways of classifying traits each of which captures some aspect of the innate/non-innate distinction. These include things such as whether a trait is canalized, whether it has a history of natural selection, whether it developed without learning or without a specific set of environmental triggers, whether it is causally correlated with the action of certain specific genes, etc. We offer an analogy: the term 'jade' was once thought to refer to a single natural kind; it was then discovered that it refers to two different chemical compounds, jadeite and nephrite. In the same way, we argue, researchers should recognize that 'innateness' refers not to a single natural kind but to a set of (possibly related) natural kinds. When this happens, it will be easier to progress in the field of biological and cognitive sciences.

  14. PHASES: a concept for a satellite-borne ultra-precise spectrophotometer

    CERN Document Server

    del Burgo, Carlos; Peacocke, Tully; 10.1088/1748-0221/5/01/P01006

    2010-01-01

    The Planet Hunting and Asteroseismology Explorer Spectrophotometer, PHASES, is a concept for a space-borne instrument to obtain flux calibrated spectra and measure micro-magnitude photometric variations of nearby stars. The science drivers are the determination of the physical properties of stars and the characterisation of planets orbiting them, to very high precision. PHASES, intended to be housed in a micro-satellite, consists of a 20 cm aperture modified Baker telescope feeding two detectors: the tracking detector, with a field of 1 degree square, and the science detector for performing spectrophotometry. The optical design has been developed with the primary goal of avoiding stray light on the science detector, while providing spectra in the wavelength range 370-960 nm with a resolving power that ranges from ~900 at 370 nm to ~200 at 960 nm. The signal to noise per resolution element obtained for a V=10 magnitude star in a 1 minute integration varies between ~ 35 and 140. An analysis of the light curve c...

  15. Evaluation of spacecraft technology programs (effects on communication satellite business ventures), volume 2

    Science.gov (United States)

    Greenburg, J. S.; Kaplan, M.; Fishman, J.; Hopkins, C.

    1985-01-01

    The computational procedures used in the evaluation of spacecraft technology programs that impact upon commercial communication satellite operations are discussed. Computer programs and data bases are described.

  16. Evaluating cloud precipitation efficiency with satellite retrievals of water isotopologues

    Science.gov (United States)

    Bailey, A.; Noone, D. C.; Wood, R.

    2015-12-01

    The efficiency with which clouds precipitate is believed to influence climate by modifying cloud lifetime and, ultimately, cloud amount. Aerosols can influence this linkage by reducing the effective radii of cloud droplets and suppressing precipitation. This relationship, however, is not unidirectional. Cloud precipitation efficiency can also regulate particle concentrations, since precipitation effectively scavenges aerosols from the atmosphere. One challenge in studying how aerosols, clouds, and precipitation processes interrelate is that observational constraints are difficult to attain. This work evaluates the ability of isotope ratios in water vapor to quantify cloud precipitation efficiency across the tropical and subtropical oceans. Theory suggests isotope ratios will record the precipitation efficiency of a convective plume, since heavier isotopologues precipitate preferentially; and a recent analysis of in situ measurements from the Mauna Loa Observatory (MLO, Hawaii, USA) verifies this to be the case. The challenge now lies in understanding whether satellite retrievals of isotope ratios in water vapor are sensitive enough to track precipitation efficiency globally. To answer this question, vertical profiles of the D/H ratio derived from NASA's Tropospheric Emission Spectrometer (TES) are first compared with the MLO in situ measurements. A qualitative match indicates the satellite retrievals can distinguish high from low precipitation efficiency convection. To expand the analysis geographically, TES profiles between 40°S and 40°N are compared with estimates of precipitation efficiency derived from the Tropical Rainfall Measuring Mission (TRMM) and ECMWF's ERA-Interim. Retrievals are binned by lower-tropospheric humidity and by vertical velocity in order to minimize large-scale thermodynamical influences. Co-located cloud retrievals provide the context necessary to evaluate the utility of these new estimates in elucidating cloud feedbacks on climate.

  17. A psychometric evaluation of the digital logic concept inventory

    Science.gov (United States)

    Herman, Geoffrey L.; Zilles, Craig; Loui, Michael C.

    2014-10-01

    Concept inventories hold tremendous promise for promoting the rigorous evaluation of teaching methods that might remedy common student misconceptions and promote deep learning. The measurements from concept inventories can be trusted only if the concept inventories are evaluated both by expert feedback and statistical scrutiny (psychometric evaluation). Classical Test Theory and Item Response Theory provide two psychometric frameworks for evaluating the quality of assessment tools. We discuss how these theories can be applied to assessment tools generally and then apply them to the Digital Logic Concept Inventory (DLCI). We demonstrate that the DLCI is sufficiently reliable for research purposes when used in its entirety and as a post-course assessment of students' conceptual understanding of digital logic. The DLCI can also discriminate between students across a wide range of ability levels, providing the most information about weaker students' ability levels.

  18. Intensive Evaluation of Satellite TV Impact on Four Alaskan Villages. Supplement to Basic ESCD Evaluation Design.

    Science.gov (United States)

    Practical Concepts, Inc., Washington, DC.

    A supplement to the final report, "Design for an Analysis and Assessment of the Education Satellite Communications Demonstration (ESCD)," this document is both: (1) a separable, sociologically oriented evaluation of the ESCD impact on Alaskan native villages; and (2) a direct extension of the work described in sections 4 and 5 in the…

  19. Team Primacy Concept (TPC) Based Employee Evaluation and Job Performance

    Science.gov (United States)

    Muniute, Eivina I.; Alfred, Mary V.

    2007-01-01

    This qualitative study explored how employees learn from Team Primacy Concept (TPC) based employee evaluation and how they use the feedback in performing their jobs. TPC based evaluation is a form of multirater evaluation, during which the employee's performance is discussed by one's peers in a face-to-face team setting. The study used Kolb's…

  20. Deep Charging Evaluation of Satellite Power and Communication System Components

    Science.gov (United States)

    Schneider, T. A.; Vaughn, J. A.; Chu, B.; Wong, F.; Gardiner, G.; Wright, K. H.; Phillips, B.

    2016-01-01

    Deep charging, in contrast to surface charging, focuses on electron penetration deep into insulating materials applied over conductors. A classic example of this scenario is an insulated wire. Deep charging can pose a threat to material integrity, and to sensitive electronics, when it gives rise to an electrostatic discharge or arc. With the advent of Electric Orbit Raising, which requires spiraling through Earth's radiation belts, satellites are subjected to high energy electron environments which they normally would not encounter. Beyond Earth orbit, missions to Jupiter and Saturn face deep charging concerns due to the high energy radiation environments. While predictions can be made about charging in insulating materials, it is difficult to extend those predictions to complicated geometries, such as the case of an insulating coating around a small wire, or a non-uniform silicone grouting on a bus bar. Therefore, to conclusively determine the susceptibility of a system to arcs from deep charging, experimental investigations must be carried out. This paper will describe the evaluation carried out by NASA's Marshall Space Flight Center on subscale flight-like samples developed by Space Systems/Loral, LLC. Specifically, deep charging evaluations of solar array wire coupons, a photovoltaic cell coupon, and a coaxial microwave transmission cable, will be discussed. The results of each evaluation will be benchmarked against control sample tests, as well as typical power system levels, to show no significant deep charging threat existed for this set of samples under the conditions tested.

  1. Evaluation of solar-air-heating central-receiver concepts

    Energy Technology Data Exchange (ETDEWEB)

    Bird, S.P.; Drost, M.K.; Williams, T.A.; Brown, D.R.; Fort, J.A.; Garrett-Price, B.A.; Hauser, S.G.; McLean, M.A.; Paluszek, A.M.; Young, J.K.

    1982-06-01

    The potential of seven proposed air-heating central receiver concepts are evaluated based on an independent, uniform of each one's performance and cost. The concepts include: metal tubes, ceramic tubes, sodium heat pipes, ceramic matrix, ceramic domes, small particles, and volumetric heat exchange. The selection of design points considered in the analysis, the method and ground rules used in formulating the conceptual designs are discussed, and each concept design is briefly described. The method, ground rules, and models used in the performance evaluation and cost analysis and the results are presented. (LEW)

  2. General Purpose Satellites: a concept for affordable low earth orbit vehicles

    OpenAIRE

    Boyd, Austin W.; Fuhs, Allen E.

    1997-01-01

    A general purpose satellite has been designed which will be launched from the Space Shuttle using a NASA Get-Away-Special (GAS) canister. The design is based upon the use of a new extended GAS canister and a low profile launch mechanism. The satellite is cylindrical. measuring 19 inches in diameter and 35 inches long. The maximum vehicle weight is 250 pounds, of which 50 pounds is dedicated to user payloads. The remaining 200 pounds encompasses the satellite structure and support ...

  3. Evaluating ITER remote handling middleware concepts

    Energy Technology Data Exchange (ETDEWEB)

    Koning, J.F., E-mail: j.f.koning@differ.nl [FOM Institute DIFFER, Association EURATOM-FOM, Partner in the Trilateral Euregio Cluster and ITER-NL, PO Box 1207, 3430 BE Nieuwegein (Netherlands); Heemskerk, C.J.M.; Schoen, P.; Smedinga, D. [Heemskerk Innovative Technology, Noordwijk (Netherlands); Boode, A.H. [University of Applied Sciences InHolland, Alkmaar (Netherlands); Hamilton, D.T. [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France)

    2013-10-15

    Highlights: ► Remote Handling Study Centre: middleware system setup and modules built. ► Aligning to ITER RH Control System Layout: prototype of database, VR and simulator. ► OpenSplice DDS, ZeroC ICE messaging and object oriented middlewares reviewed. ► Windows network latency found problematic for semi-realtime control over the network. -- Abstract: Remote maintenance activities in ITER will be performed by a unique set of hardware systems, supported by an extensive software kit. A layer of middleware will manage and control a complex set of interconnections between teams of operators, hardware devices in various operating theatres, and databases managing tool and task logistics. The middleware is driven by constraints on amounts and timing of data like real-time control loops, camera images, and database access. The Remote Handling Study Centre (RHSC), located at FOM institute DIFFER, has a 4-operator work cell in an ITER relevant RH Control Room setup which connects to a virtual hot cell back-end. The centre is developing and testing flexible integration of the Control Room components, resulting in proof-of-concept tests of this middleware layer. SW components studied include generic human-machine interface software, a prototype of a RH operations management system, and a distributed virtual reality system supporting multi-screen, multi-actor, and multiple independent views. Real-time rigid body dynamics and contact interaction simulation software supports simulation of structural deformation, “augmented reality” operations and operator training. The paper presents generic requirements and conceptual design of middleware components and Operations Management System in the context of a RH Control Room work cell. The simulation software is analyzed for real-time performance and it is argued that it is critical for middleware to have complete control over the physical network to be able to guarantee bandwidth and latency to the components.

  4. Orbit Determination of the SELENE Satellites Using Multi-Satellite Data Types and Evaluation of SELENE Gravity Field Models

    Science.gov (United States)

    Goossens, S.; Matsumoto, K.; Noda, H.; Araki, H.; Rowlands, D. D.; Lemoine, F. G.

    2011-01-01

    The SELENE mission, consisting of three separate satellites that use different terrestrial-based tracking systems, presents a unique opportunity to evaluate the contribution of these tracking systems to orbit determination precision. The tracking data consist of four-way Doppler between the main orbiter and one of the two sub-satellites while the former is over the far side, and of same-beam differential VLBI tracking between the two sub-satellites. Laser altimeter data are also used for orbit determination. The contribution to orbit precision of these different data types is investigated through orbit overlap analysis. It is shown that using four-way and VLBI data improves orbit consistency for all satellites involved by reducing peak values in orbit overlap differences that exist when only standard two-way Doppler and range data are used. Including laser altimeter data improves the orbit precision of the SELENE main satellite further, resulting in very smooth total orbit errors at an average level of 18m. The multi-satellite data have also resulted in improved lunar gravity field models, which are assessed through orbit overlap analysis using Lunar Prospector tracking data. Improvements over a pre-SELENE model are shown to be mostly in the along-track and cross-track directions. Orbit overlap differences are at a level between 13 and 21 m with the SELENE models, depending on whether l-day data overlaps or I-day predictions are used.

  5. PHASES: a concept for a satellite-borne ultra-precise spectrophotometer

    Energy Technology Data Exchange (ETDEWEB)

    Burgo, C del [UNINOVA-CA3, Campus da Caparica, Quinta da Torre, Monte de Caparica 2825-149, Caparica (Portugal); Prieto, C Allende [Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, Surrey RH5 6NT (United Kingdom); Peacocke, T, E-mail: cburgo@uninova.p [Experimental Physics, National University of Ireland, Maynooth, Co. Kildare (Ireland)

    2010-01-15

    The Planet Hunting and Asteroseismology Explorer Spectrophotometer, PHASES, is a concept for a space-borne instrument to obtain flux calibrated spectra and measure micro-magnitude photometric variations of nearby stars. The science drivers are the determination of the physical properties of stars and the characterisation of planets orbiting them, to very high precision. PHASES, intended to be housed in a micro-satellite, consists of a 20 cm aperture modified Baker telescope feeding two detectors: the tracking detector, with a field of 1 degree square, and the science detector for performing spectrophotometry. The optical design has been developed with the primary goal of avoiding stray light on the science detector, while providing spectra in the wavelength range 370-960 nm with a resolving power that ranges from {approx} 900 at 370 nm to {approx} 200 at 960 nm. The signal to noise per resolution element obtained for a V = 10 magnitude star in a 1 minute integration varies between {approx} 35 and 140. An analysis of the light curve constrains the radii of the planets relative to their parent stars' radii, which are, in turn, tightly constrained by the combination of absolute spectrophotometry and trigonometric parallaxes. The provisional optical design satisfies all the scientific requirements, including a {approx} 1% rms flux calibration strategy based on observations of bright A-type stars and model atmospheres, allowing the determination of stellar angular diameters for nearby solar-like stars to 0.5%. This level of accuracy will be propagated to the stellar radii for the nearest stars, with highly reliable Hipparcos parallaxes, and more significantly, to the planetary radii.

  6. Initial Design and Concept of Operations for a Clandestine Data Relay UUV To Circumvent Jungle Canopy Effects on Satellite Communications

    Science.gov (United States)

    2011-09-01

    18 Grant Ehrlich, "Lithium-Ion Batteries ," In Handbook of Batteries (Third Edition), ed. D. Linden and T. Reddy, (New York: McGraw...Ehrlich, Grant. "Lithium-Ion Batteries ." In Handbook of Batteries (Third Edition), edited by D. Linden and T. Reddy, 35.1–35.94, New York...Concept of Operations for a Clandestine Data Relay UUV To Circumvent Jungle Canopy Effects on Satellite Communications 6. AUTHOR( S ) Michael G.Tyree

  7. Re-evaluation of monitored retrievable storage concepts

    Energy Technology Data Exchange (ETDEWEB)

    Fletcher, J.F.; Smith, R.I.

    1989-04-01

    In 1983, as a prelude to the monitored retrievable storage (MRS) facility conceptual design, the Pacific Northwest Laboratory (PNL) conducted an evaluation for the US Department of Energy (DOE) that examined alternative concepts for storing spent LWR fuel and high- level wastes from fuel reprocessing. The evaluation was made considering nine concepts for dry away-from-reactor storage. The nine concepts evaluated were: concrete storage cask, tunnel drywell, concrete cask-in-trench, open-cycle vault, metal casks (transportable and stationary), closed-cycle vault, field drywell, and tunnel-rack vault. The purpose and scope of the re-evaluation did not require a repetition of the expert-based examinations used earlier. Instead, it was based on more detailed technical review by a small group, focusing on changes that had occurred since the initial evaluation was made. Two additional storage concepts--the water pool and the horizontal modular storage vault (NUHOMS system)--were ranked along with the original nine. The original nine concepts and the added two conceptual designs were modified as appropriate for a scenario with storage capacity for 15,000 MTU of spent fuel. Costs, area requirements, and technical and historical data pertaining to MRS storage were updated for each concept.

  8. Evaluation of Computer Simulations for Teaching Apparel Merchandising Concepts.

    Science.gov (United States)

    Jolly, Laura D.; Sisler, Grovalynn

    1988-01-01

    The study developed and evaluated computer simulations for teaching apparel merchandising concepts. Evaluation results indicated that teaching method (computer simulation versus case study) does not significantly affect cognitive learning. Student attitudes varied, however, according to topic (profitable merchandising analysis versus retailing…

  9. Evaluation of Computer Simulations for Teaching Apparel Merchandising Concepts.

    Science.gov (United States)

    Jolly, Laura D.; Sisler, Grovalynn

    1988-01-01

    The study developed and evaluated computer simulations for teaching apparel merchandising concepts. Evaluation results indicated that teaching method (computer simulation versus case study) does not significantly affect cognitive learning. Student attitudes varied, however, according to topic (profitable merchandising analysis versus retailing…

  10. A COMPARISON OF SEMANTIC SIMILARITY MODELS IN EVALUATING CONCEPT SIMILARITY

    Directory of Open Access Journals (Sweden)

    Q. X. Xu

    2012-08-01

    Full Text Available The semantic similarities are important in concept definition, recognition, categorization, interpretation, and integration. Many semantic similarity models have been established to evaluate semantic similarities of objects or/and concepts. To find out the suitability and performance of different models in evaluating concept similarities, we make a comparison of four main types of models in this paper: the geometric model, the feature model, the network model, and the transformational model. Fundamental principles and main characteristics of these models are introduced and compared firstly. Land use and land cover concepts of NLCD92 are employed as examples in the case study. The results demonstrate that correlations between these models are very high for a possible reason that all these models are designed to simulate the similarity judgement of human mind.

  11. a Comparison of Semantic Similarity Models in Evaluating Concept Similarity

    Science.gov (United States)

    Xu, Q. X.; Shi, W. Z.

    2012-08-01

    The semantic similarities are important in concept definition, recognition, categorization, interpretation, and integration. Many semantic similarity models have been established to evaluate semantic similarities of objects or/and concepts. To find out the suitability and performance of different models in evaluating concept similarities, we make a comparison of four main types of models in this paper: the geometric model, the feature model, the network model, and the transformational model. Fundamental principles and main characteristics of these models are introduced and compared firstly. Land use and land cover concepts of NLCD92 are employed as examples in the case study. The results demonstrate that correlations between these models are very high for a possible reason that all these models are designed to simulate the similarity judgement of human mind.

  12. CHASER: An Innovative Satellite Mission Concept to Measure the Effects of Aerosols on Clouds and Climate

    Science.gov (United States)

    Renno, N.; Williams, E.; Rosenfeld, D.; Fischer, D.; Fischer, J.; Kremic, T.; Agrawal, A.; Andreae, M.; Bierbaum, R.; Blakeslee, R.; Boerner, A.; Bowles, N.; Christian, H.; Dunion, J.; Horvath, A.; Huang, X.; Khain, A.; Kinne, S.; Lemos, M.-C.; Penner, J.

    2012-04-01

    The formation of cloud droplets on aerosol particles, technically known as the activation of cloud condensation nuclei (CCN), is the fundamental process driving the interactions of aerosols with clouds and precipitation. Knowledge of these interactions is foundational to our understanding of weather and climate. The Intergovernmental Panel on Climate Change (IPCC) and the Decadal Survey (NRC 2007) indicate that the uncertainty in how clouds adjust to aerosol perturbations dominates the uncertainty in the overall quantification of the radiative forcing attributable to human activities. The Clouds, Hazards, and Aerosols Survey for Earth Researchers (CHASER) mission concept responds to the IPCC and Decadal Survey concerns by studying the activation of CCN and their interactions with clouds and storms. CHASER proposes to revolutionize our understanding of the interactions of aerosols with clouds by making the first global measurements of the fundamental physical entity linking them: activated cloud condensation nuclei. The CHASER mission was conceptualized to measure all quantities necessary for determining the interactions of aerosols with clouds and storms. Measurements by current satellites allow the determination of crude profiles of cloud particle size but not of the activated CCN that seed them. CHASER uses a new technique (Freud et al. 2011; Rosenfeld et al. 2012) and high-heritage instruments to produce the first global maps of activated CCN and the properties of the clouds associated with them. CHASER measures the CCN concentration and cloud thermodynamic forcing simultaneously, allowing their effects to be distinguished. Changes in the behavior of a group of weather systems in which only one of the quantities varies (a partial derivative of the intensity with the desirable quantity) allow the determination of each effect statistically. The high uncertainties of current climate predictions limit their much-needed use in decision-making. CHASER mitigates this

  13. Evaluation of Veda, Inc. , central receiver solar collection system concept

    Energy Technology Data Exchange (ETDEWEB)

    Ator, J.

    1981-08-01

    The Unified Heliostat Array (UHA) is a geometrical heliostat field layout with rows of mirrors placed at various levels on terraces. The Veda Industrial Heliostat (VIH) is a toroidal segment mirror mounted on an equatorial mount. These two concepts are evaluated to assess the credibility of the optical designs and the validity of UHA and VIH performance estimates, to determine what the distinctive features embodied in UHA AND VIH concepts offer that more conventional central receiver technologies do not, and to determine where the UHA and VIH concepts might be most applicable in DOE's Solar Thermal Program. The UHA area efficiency, flux density distribution, and beam safety are evaluated, and the feasibility of using a secondary mirror and the potential for special applications are assessed. The optical design, equatorial mount, and manufacturability of the VIH are evaluated. (LEW)

  14. Concepts for evaluation of sound insulation of dwellings

    DEFF Research Database (Denmark)

    Rasmussen, Birgit; Rindel, Jens Holger

    2005-01-01

    Legal sound insulation requirements have existed more than 50 years in some countries, and single-number quantities for evaluation of sound insulation have existed nearly as long time. However, the concepts have changed considerably over time from simple arithmetic averaging of frequency bands....... The concepts suitable for evaluation should be well-defined under practical situations in buil¬dings, be measurable, reproducible and of course correlate well with subjective evalua¬tion. More noise sources - incl. neighbours’ activities - and an increased demand for high quality and comfort together...... with a trend towards light-weight constructions are contradictory and challenging. This calls for exchange of data and experience, implying a need for harmonized concepts, including use of spectrum adaptation terms. The paper will provide input for future discussions in EAA TC-RBA WG4: "Sound insulation...

  15. Introducing multisensor satellite radiance-based evaluation for regional Earth System modeling

    Science.gov (United States)

    Matsui, T.; Santanello, J.; Shi, J. J.; Tao, W.-K.; Wu, D.; Peters-Lidard, C.; Kemp, E.; Chin, M.; Starr, D.; Sekiguchi, M.; Aires, F.

    2014-07-01

    Earth System modeling has become more complex, and its evaluation using satellite data has also become more difficult due to model and data diversity. Therefore, the fundamental methodology of using satellite direct measurements with instrumental simulators should be addressed especially for modeling community members lacking a solid background of radiative transfer and scattering theory. This manuscript introduces principles of multisatellite, multisensor radiance-based evaluation methods for a fully coupled regional Earth System model: NASA-Unified Weather Research and Forecasting (NU-WRF) model. We use a NU-WRF case study simulation over West Africa as an example of evaluating aerosol-cloud-precipitation-land processes with various satellite observations. NU-WRF-simulated geophysical parameters are converted to the satellite-observable raw radiance and backscatter under nearly consistent physics assumptions via the multisensor satellite simulator, the Goddard Satellite Data Simulator Unit. We present varied examples of simple yet robust methods that characterize forecast errors and model physics biases through the spatial and statistical interpretation of various satellite raw signals: infrared brightness temperature (Tb) for surface skin temperature and cloud top temperature, microwave Tb for precipitation ice and surface flooding, and radar and lidar backscatter for aerosol-cloud profiling simultaneously. Because raw satellite signals integrate many sources of geophysical information, we demonstrate user-defined thresholds and a simple statistical process to facilitate evaluations, including the infrared-microwave-based cloud types and lidar/radar-based profile classifications.

  16. Introducing Multisensor Satellite Radiance-Based Evaluation for Regional Earth System Modeling

    Science.gov (United States)

    Matsui, T.; Santanello, J.; Shi, J. J.; Tao, W.-K.; Wu, D.; Peters-Lidard, C.; Kemp, E.; Chin, M.; Starr, D.; Sekiguchi, M.; hide

    2014-01-01

    Earth System modeling has become more complex, and its evaluation using satellite data has also become more difficult due to model and data diversity. Therefore, the fundamental methodology of using satellite direct measurements with instrumental simulators should be addressed especially for modeling community members lacking a solid background of radiative transfer and scattering theory. This manuscript introduces principles of multisatellite, multisensor radiance-based evaluation methods for a fully coupled regional Earth System model: NASA-Unified Weather Research and Forecasting (NU-WRF) model. We use a NU-WRF case study simulation over West Africa as an example of evaluating aerosol-cloud-precipitation-land processes with various satellite observations. NU-WRF-simulated geophysical parameters are converted to the satellite-observable raw radiance and backscatter under nearly consistent physics assumptions via the multisensor satellite simulator, the Goddard Satellite Data Simulator Unit. We present varied examples of simple yet robust methods that characterize forecast errors and model physics biases through the spatial and statistical interpretation of various satellite raw signals: infrared brightness temperature (Tb) for surface skin temperature and cloud top temperature, microwave Tb for precipitation ice and surface flooding, and radar and lidar backscatter for aerosol-cloud profiling simultaneously. Because raw satellite signals integrate many sources of geophysical information, we demonstrate user-defined thresholds and a simple statistical process to facilitate evaluations, including the infrared-microwave-based cloud types and lidar/radar-based profile classifications.

  17. Modeling Energy and Development : An Evaluation of Models and Concepts

    NARCIS (Netherlands)

    Ruijven, Bas van; Urban, Frauke; Benders, René M.J.; Moll, Henri C.; Sluijs, Jeroen P. van der; Vries, Bert de; Vuuren, Detlef P. van

    2008-01-01

    Most global energy models are developed by institutes from developed countries focusing primarily oil issues that are important in industrialized countries. Evaluation of the results for Asia of the IPCC/SRES models shows that broad concepts of energy and development. the energy ladder and the envir

  18. Evaluation of TENCompetence proof of concept assessment tools

    NARCIS (Netherlands)

    Petrov, Milen; Aleksieva-Petrova, Adelina; Stefanov, Krassen; Schoonenboom, Judith; Miao, Yongwu

    2008-01-01

    Petrov, M., Aleksieva-Petrova, A., Stefanov, K., Schoonenboom, J., & Miao, Y. (2008). Evaluation of TENCompetence proof of concept assessment tools. In H. W. Sligte & R. Koper (Eds.). Proceedings of the 4th TENCompetence Open Workshop. Empowering Learners for Lifelong Competence Development: pedagog

  19. Evaluation of TENCompetence proof of concept assessment tools

    NARCIS (Netherlands)

    Petrov, Milen; Aleksieva-Petrova, Adelina; Stefanov, Krassen; Schoonenboom, Judith; Miao, Yongwu

    2008-01-01

    Petrov, M., Aleksieva-Petrova, A., Stefanov, K., Schoonenboom, J., & Miao, Y. (2008). Evaluation of TENCompetence proof of concept assessment tools. In H. W. Sligte & R. Koper (Eds.). Proceedings of the 4th TENCompetence Open Workshop. Empowering Learners for Lifelong Competence Development: pedagog

  20. Health system guidance appraisal-concept evaluation and usability testing

    OpenAIRE

    2016-01-01

    Background Health system guidance (HSG) provides recommendations aimed to address health system challenges. However, there is a paucity of methods to direct, appraise, and report HSG. Earlier research identified 30 candidate criteria (concepts) that can be used to evaluate the quality of HSG and guide development and reporting requirements. The objective of this paper was to describe two studies aimed at evaluating the importance of these 30 criteria, design a draft HSG appraisal tool, and te...

  1. Evaluation of pulsed RFI effects on digital satellite repeaters

    Science.gov (United States)

    Huang, T. C.; Braun, W. R.

    1980-01-01

    This paper presents an analytical approach for assessing the effect of pulsed RFI on the error probability of a coherent phase-shift keyed signal through a nonlinear satellite repeater. The RFI is assumed to affect the uplink channel and to consist of CW pulses with random power levels and arriving randomly in time with a Poisson distribution. A model to approximate the effect of intermodulation products is introduced and the error probability conditioned on the output of the satellite repeater is computed. The classical moment technique is then used as an efficient method of averaging the conditional error probability over the numerous random parameters associated with the uplink signal.

  2. Social Context in Usability Evaluations: Concepts, Processes and Products

    DEFF Research Database (Denmark)

    Jensen, Janne Jul

    This thesis addresses social context of usability evaluations. Context plays an important role in usability evaluations. A major part of the context of a usability evaluation is the people involved. This is also often referred to as the social context of the usability evaluation, and although...... social context is considered important, only little research has been done to identify how it influences usability evaluations. In this thesis I explore how social context affects the process and product of a usability evaluation and explain the findings in terms of the theory of behaviour settings...... and a field experiment. Findings from these activities are presented in five published paper contributions. I furthermore introduce the theory of behaviour settings as a tool to help characterise the key concepts of social context which, together with an understanding of usability evaluations, provide...

  3. Evaluation of the breed/burn fast reactor concept

    Energy Technology Data Exchange (ETDEWEB)

    Atefi, B.; Driscoll, M.J.; Lanning, D.D.

    1979-12-01

    A core design concept and fuel management strategy, designated breed/burn, has been evaluated for heterogeneous fast breeder reactors. In this concept internal blanket assemblies after fissile material is bred in over several incore cycles, are shuffled into a moderated radial blanket and/or central island. The most promising materials combination identified used thorium in the internal blankets (due to the superior performance of epithermal Th-U233 systems) and zirconium hydride (ZrH/sub 16/) as the moderator (because of the compact assembly and core designs it permitted).

  4. 'You can get there from here': Advanced low cost propulsion concepts for small satellites beyond LEO

    Energy Technology Data Exchange (ETDEWEB)

    Baker, Adam M.; Silva Curiel, Alex da; Sweeting, Martin [Surrey Satellite Technology Ltd., Surrey (United Kingdom); Schaffner, Jake [California Polytechnic State Univ., San Luis Obispo, CA (United States)

    2005-10-15

    Small satellites have historically been forced to use low cost propulsion, or to do without in order to maintain low cost. Since 1999 an increasing number of SSTL's customers have demanded the capability to precisely position and subsequently manoeuvre their satellites, driven largely by the current attraction of small satellite constellations such as Disaster Monitoring (DMC), which require propulsion for launcher injection error correction, drag compensation, constellation phasing and proximity manoeuvring and rendezvous. SSTL has successfully flight qualified a simple, low cost propulsion system based on a low power (15-100 W) resistojet employing green propellants such as butane and xenon, and demonstrated key constellation manoeuvres. The system is capable of up to 60 m/s deltaV and will be described here. The SSTL low power resistojet is however limited by a low Isp ( about 50s for Xenon in the present design, and about 100s with nitrogen and butane) and a slow reaction time (10 min warm-up required). An increasing desire to apply small satellite technology to high deltaV missions while retaining the low cost aspect demands new solutions. 'Industry standard' solutions based on cryogenic propulsion, or toxic, carcinogenic storable propellants such as hydrazine/nitrogen oxides combination are not favourable for small satellite missions developed within SSTL's low cost engineering environment. This paper describes a number of strawman missions with high deltaV and/or precision manoeuvring requirements and some low cost propulsion solutions which have been explored at the Surrey Space Centre to meet future needs: (1) Deployment of a complex constellation of nano- or pico-satellites from a secondary launch to a new orbit. The S3TV concept has been developed to allow deployment up to 12 payloads from an 'off-the-shelf' thrust tube, using a restartable nitrous oxide hybrid engine, operating in a dual mode with resistojets for attitude

  5. Satellite Power Systems (SPS) concept definition study. Volume 2, part 2: System engineering

    Science.gov (United States)

    Hanley, G. M.

    1980-09-01

    The latest technical and programmatic developments are considered as well as expansions of the Rockwell SPS cost model covering each phase of the program through the year 2030. Comparative cost/economic analyses cover elements of the satellite, construction system, space transportation vehicles and operations, and the ground receiving station. System plans to define time phased costs and planning requirements that support major milestones through the year 2000. A special analysis is included on natural resources required to build the SPS reference configuration. An appendix contains the SPS Work Breakdown Structure and dictionary along with detail cost data sheet on each system and main element of the program. Over 200 line items address DDT&E, theoretical first unit, investment cost per satellite, and operations charges for replacement capital and normal operations and maintenance costs.

  6. Satellite Power Systems (SPS) concept definition study. Volume 2, part 2: System engineering. [cost and programmatics

    Science.gov (United States)

    Hanley, G. M.

    1980-01-01

    The latest technical and programmatic developments are considered as well as expansions of the Rockwell SPS cost model covering each phase of the program through the year 2030. Comparative cost/economic analyses cover elements of the satellite, construction system, space transportation vehicles and operations, and the ground receiving station. System plans to define time phased costs and planning requirements that support major milestones through the year 2000. A special analysis is included on natural resources required to build the SPS reference configuration. An appendix contains the SPS Work Breakdown Structure and dictionary along with detail cost data sheet on each system and main element of the program. Over 200 line items address DDT&E, theoretical first unit, investment cost per satellite, and operations charges for replacement capital and normal operations and maintenance costs.

  7. Performance Evaluation of Machine Learning Algorithms for Urban Pattern Recognition from Multi-spectral Satellite Images

    Directory of Open Access Journals (Sweden)

    Marc Wieland

    2014-03-01

    Full Text Available In this study, a classification and performance evaluation framework for the recognition of urban patterns in medium (Landsat ETM, TM and MSS and very high resolution (WorldView-2, Quickbird, Ikonos multi-spectral satellite images is presented. The study aims at exploring the potential of machine learning algorithms in the context of an object-based image analysis and to thoroughly test the algorithm’s performance under varying conditions to optimize their usage for urban pattern recognition tasks. Four classification algorithms, Normal Bayes, K Nearest Neighbors, Random Trees and Support Vector Machines, which represent different concepts in machine learning (probabilistic, nearest neighbor, tree-based, function-based, have been selected and implemented on a free and open-source basis. Particular focus is given to assess the generalization ability of machine learning algorithms and the transferability of trained learning machines between different image types and image scenes. Moreover, the influence of the number and choice of training data, the influence of the size and composition of the feature vector and the effect of image segmentation on the classification accuracy is evaluated.

  8. Web 2.0 Learning Environment: Concept, Implementation, Evaluation

    OpenAIRE

    Blees, Ingo; Rittberger, Marc

    2009-01-01

    This contribution presents and evaluates a new learning environment model based on Web 2.0 applications. In a theoretical overview the concepts of eLearning 2.0 and Personal Learning Environments are introduced, along with their main aspects of autonomy, creativity and networking, and relate them to the didactics of constructivism and connectivism. The requirements and basic functional components for the development of our particular Web 2.0 learning environment are derived from these. The le...

  9. IPONS - A New Concept for Integrated Power and Data Distribution Onboard Satellites

    Science.gov (United States)

    Scholz, O.; Gotsmann, M.; Dostert, K.; Gollor, M.

    2007-08-01

    IPONS ( Information & PO wer Net works in Spacecrafts) is an initiative launched by Astrium Satellites to investigate the classical idea of "Power Line Communications" (PLC) technology for development of advanced electrical S/C architectures with combined Power Networks & Data Links. A gross saving of up to 50% of harness mass in addition to significant savings in engineering costs and time is envisaged. An assessment of PLC transmission techniques has been performed targeting Medium Data Rates > 1MBit/s. As a result the use of typical Twisted Pair Power Harness with special terminations for impedance control is proposed. Thus simple modulation schemes for data transmission can be used avoiding complex signal processors in favour of simple and inexpensive FPGA or ASIC solutions.

  10. Performance-based concept on seismic evaluation of existing bridges

    Institute of Scientific and Technical Information of China (English)

    Yu-Chi Sung; Wen-I Liao; W.Phillip Yen

    2009-01-01

    Conventional seismic evaluation of existing bridges explores the ability of a bridge to survive under significant earthquake excitations. This approach has several major drawbacks, such as only a single structural performance of near collapse is considered, and the simplified approach of adopting strength-based concept to indirectly estimate the nonlinear behavior of a structure lacks accuracy. As a result, performance-based concepts that include a wider variety of structural performance states of a given bridge excited by different levels of earthquake intensity is needed by the engineering community. This paper introduces an improved process for the seismic evaluation of existing bridges. The relationship between the overall structural performance and earthquakes with varying levels of peak ground acceleration (PGA) can successfully be linked. A universal perspective on the seismic evaluation of bridges over their entire life-cycle can be easily obtained to investigate multiple performance objectives. The accuracy of the proposed method, based on pushover analysis, is proven in a case study that compares the results from the proposed procedure with additional nonlinear time history analyses.

  11. Evaluation of satellite rainfall products through hydrologic simulation in a fully distributed hydrologic model

    Science.gov (United States)

    Bitew, Menberu M.; Gebremichael, Mekonnen

    2011-06-01

    The goal of this study is to evaluate the accuracy of four global high-resolution satellite rainfall products (CMORPH, TMPA 3B42RT, TMPA 3B42, and PERSIANN) through the hydrologic simulation of a 1656 km2 mountainous watershed in the fully distributed MIKE SHE hydrologic model. This study shows that there are significant biases in the satellite rainfall estimates and large variations in rainfall amounts, leading to large variations in hydrologic simulations. The rainfall algorithms that use primarily microwave data (CMORPH and TMPA 3B42RT) show consistent and better performance in streamflow simulation (bias in the order of -53% to -3%, Nash-Sutcliffe efficiency (NSE) from 0.34 to 0.65); the rainfall algorithm that uses primarily infrared data (PERSIANN) shows lower performance (bias from -82% to -3%, Nash-Sutcliffe efficiency from -0.39 to 0.43); and the rainfall algorithm that merges the satellite data with rain gage data (TMPA 3B42) shows inconsistencies and the lowest performance (bias from -86% to 0.43%, Nash-Sutcliffe efficiency from -0.50 to 0.27). A dilemma between calibrating the hydrologic model with rain gage data and calibrating it with the corresponding satellite rainfall data is presented. Calibrating the model with corresponding satellite rainfall data increases the performance of satellite streamflow simulation compared to the model calibrated with rain gage data, but decreases the performance of satellite evapotranspiration simulation.

  12. Evaluating the Effect of Global Positioning System (GPS) Satellite Clock Error via GPS Simulation

    Science.gov (United States)

    Sathyamoorthy, Dinesh; Shafii, Shalini; Amin, Zainal Fitry M.; Jusoh, Asmariah; Zainun Ali, Siti

    2016-06-01

    This study is aimed at evaluating the effect of Global Positioning System (GPS) satellite clock error using GPS simulation. Two conditions of tests are used; Case 1: All the GPS satellites have clock errors within the normal range of 0 to 7 ns, corresponding to pseudorange error range of 0 to 2.1 m; Case 2: One GPS satellite suffers from critical failure, resulting in clock error in the pseudorange of up to 1 km. It is found that increase of GPS satellite clock error causes increase of average positional error due to increase of pseudorange error in the GPS satellite signals, which results in increasing error in the coordinates computed by the GPS receiver. Varying average positional error patterns are observed for the each of the readings. This is due to the GPS satellite constellation being dynamic, causing varying GPS satellite geometry over location and time, resulting in GPS accuracy being location / time dependent. For Case 1, in general, the highest average positional error values are observed for readings with the highest PDOP values, while the lowest average positional error values are observed for readings with the lowest PDOP values. For Case 2, no correlation is observed between the average positional error values and PDOP, indicating that the error generated is random.

  13. Concept for a Lunar Transfer Vehicle for Small Satellite Delivery to the Moon from the International Space Station

    Science.gov (United States)

    Elliott, John; Alkalai, Leon

    2010-01-01

    The International Space Station (ISS) has developed as a very capable center for scientific research in Lower Earth Orbit. An additional potential of the ISS that has not thus far been exploited, is the use of this orbiting plat-form for the assembly and launching of vehicles that could be sent to more distant destinations. This paper reports the results of a recent study that looked at an architecture and conceptual flight system design for a lunar transfer vehicle (LTV) that could be delivered to the ISS in segments, assembled, loaded with payload and launched from the ISS with the objective of delivering multiple small and micro satellites to lunar orbit. The design of the LTV was optimized for low cost and high payload capability, as well as ease of assembly. The resulting design would use solar electric propulsion (SEP) to carry a total payload mass of 250 kg from the ISS to a 100 km lunar orbit. A preliminary concept of operations was developed considering currently available delivery options and ISS capabili-ties that should prove flexible enough to accommodate a variety of payloads and missions. This paper will present an overview of the study, including key trades, mission and flight system design, and notional operational concept.

  14. The Strengths and Limitations of Satellite Data for Evaluating Tropospheric Processes in Chemistry-Climate Models

    Science.gov (United States)

    Duncan, Bryan

    2012-01-01

    There is now a wealth of satellite data products available with which to evaluate a model fs simulation of tropospheric composition and other model processes. All of these data products have their strengths and limitations that need to be considered for this purpose. For example, uncertainties are introduced into a data product when 1) converting a slant column to a vertical column and 2) estimating the amount of a total column of a trace gas (e.g., ozone, nitrogen dioxide) that resides in the troposphere. Oftentimes, these uncertainties are not well quantified and the satellite data products are not well evaluated against in situ observations. However, these limitations do not preclude us from using these data products to evaluate our model processes if we understand these strengths and limitations when developing diagnostics. I will show several examples of how satellite data products are being used to evaluate particular model processes with a focus on the strengths and limitations of these data products. In addition, I will introduce the goals of a newly formed team to address issues on the topic of "satellite data for improved model evaluation and process studies" that is established in support of the IGAC/SPARC Global Chemistry ]Climate Modeling and Evaluation Workshop.

  15. Concept Maps for Evaluating Learning of Sustainable Development

    Science.gov (United States)

    Shallcross, David C.

    2016-01-01

    Concept maps are used to assess student and cohort learning of sustainable development. The concept maps of 732 first-year engineering students were individually analyzed to detect patterns of learning and areas that were not well understood. Students were given 20 minutes each to prepare a concept map of at least 20 concepts using paper and pen.…

  16. Concept Maps for Evaluating Learning of Sustainable Development

    Science.gov (United States)

    Shallcross, David C.

    2016-01-01

    Concept maps are used to assess student and cohort learning of sustainable development. The concept maps of 732 first-year engineering students were individually analyzed to detect patterns of learning and areas that were not well understood. Students were given 20 minutes each to prepare a concept map of at least 20 concepts using paper and pen.…

  17. Lecture Evaluations by Medical Students: Concepts That Correlate With Scores.

    Science.gov (United States)

    Jen, Aaron; Webb, Emily M; Ahearn, Bren; Naeger, David M

    2016-01-01

    The didactic lecture remains one of the most popular teaching formats in medical education; yet, factors that most influence lecturing success in radiology education are unknown. The purpose of this study is to identify patterns of narrative student feedback that are associated with relatively higher and lower evaluation scores. All student evaluations from our core radiology elective during 1 year were compiled. All evaluation comments were tagged, to identify discrete descriptive concepts. Correlation coefficients were calculated, for each tag with mean evaluation scores. Tags that were the most strongly associated with the highest- versus lowest-rated (> or lectures were identified. A total of 3,262 comments, on 273 lectures, rated by 77 senior medical students, were analyzed. The mean lecture score was 8.96 ± 0.62. Three tags were significantly positively correlated with lecture score: "interactive"; "fun/engaging"; and "practical/important content" (r = 0.39, r = 0.34, and r = 0.32, respectively; all P lectures yielded similar results. Several factors were identified that were strongly associated with lecture score. Among the actionable characteristics, interactive lectures with appropriately targeted content (ie, practical/useful) were the most highly rated. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  18. Group concept mapping for evaluation and development in nursing education.

    Science.gov (United States)

    Hagell, Peter; Edfors, Ellinor; Hedin, Gita; Westergren, Albert; Hammarlund, Catharina Sjödahl

    2016-09-01

    The value of course evaluations has been debated since they frequently fail to capture the complexity of education and learning. Group Concept Mapping (GCM), a participant-centred mixed-method was explored as a tool for evaluation and development in nursing education and to better understand students' learning experiences, using data from a GCM-based evaluation of a research training assignment integrating clinical practice and research data collection within a Swedish university nursing program. Student nurses (n = 47) participated in a one-day GCM exercise. Focus group brainstorming regarding experiences from the assignment that the students considered important and instructive yielded 98 statements that were individually sorted based on their student-perceived relationships, and rated regarding their importance/instructiveness and need for development. Quantitative analysis of sort data produced a 2-dimensional map representing their conceptual relationships, and eight conceptual areas. Average cluster ratings were plotted relative to each other and provided a decision aid for development and planning by identifying areas (i.e., "Research methodology", "Patients' perspectives", and "Interviewer role") considered highly important/instructive and in high need for development. These experiences illustrate the use and potential of GCM as an interactive participant-centred approach to evaluation, planning and development in nursing and other higher health science educations.

  19. Uncertainties in Steric Sea Level Change Estimation During the Satellite Altimeter Era: Concepts and Practices

    Science.gov (United States)

    MacIntosh, C. R.; Merchant, C. J.; von Schuckmann, K.

    2016-10-01

    This article presents a review of current practice in estimating steric sea level change, focussed on the treatment of uncertainty. Steric sea level change is the contribution to the change in sea level arising from the dependence of density on temperature and salinity. It is a significant component of sea level rise and a reflection of changing ocean heat content. However, tracking these steric changes still remains a significant challenge for the scientific community. We review the importance of understanding the uncertainty in estimates of steric sea level change. Relevant concepts of uncertainty are discussed and illustrated with the example of observational uncertainty propagation from a single profile of temperature and salinity measurements to steric height. We summarise and discuss the recent literature on methodologies and techniques used to estimate steric sea level in the context of the treatment of uncertainty. Our conclusions are that progress in quantifying steric sea level uncertainty will benefit from: greater clarity and transparency in published discussions of uncertainty, including exploitation of international standards for quantifying and expressing uncertainty in measurement; and the development of community "recipes" for quantifying the error covariances in observations and from sparse sampling and for estimating and propagating uncertainty across spatio-temporal scales.

  20. Uncertainties in Steric Sea Level Change Estimation During the Satellite Altimeter Era: Concepts and Practices

    Science.gov (United States)

    MacIntosh, C. R.; Merchant, C. J.; von Schuckmann, K.

    2017-01-01

    This article presents a review of current practice in estimating steric sea level change, focussed on the treatment of uncertainty. Steric sea level change is the contribution to the change in sea level arising from the dependence of density on temperature and salinity. It is a significant component of sea level rise and a reflection of changing ocean heat content. However, tracking these steric changes still remains a significant challenge for the scientific community. We review the importance of understanding the uncertainty in estimates of steric sea level change. Relevant concepts of uncertainty are discussed and illustrated with the example of observational uncertainty propagation from a single profile of temperature and salinity measurements to steric height. We summarise and discuss the recent literature on methodologies and techniques used to estimate steric sea level in the context of the treatment of uncertainty. Our conclusions are that progress in quantifying steric sea level uncertainty will benefit from: greater clarity and transparency in published discussions of uncertainty, including exploitation of international standards for quantifying and expressing uncertainty in measurement; and the development of community "recipes" for quantifying the error covariances in observations and from sparse sampling and for estimating and propagating uncertainty across spatio-temporal scales.

  1. Concepts and criteria for evaluating topsoil substitutes: The Texas experience

    Energy Technology Data Exchange (ETDEWEB)

    Askenasy, P.; Senkayi, A.L. [Railroad Commission of Texas, Austin, TX (United States); Joseph, W.L. [Office of Surface Mining, Alton, IL (United States)

    1997-12-31

    Presented in this paper are: (1) historical background, (2) Federal and State regulatory basis and authority, and (3) justification for selected criteria and parameters which are currently used to evaluate the quality of topsoil-substitute materials and postmine soils in Texas. The specific parameters and concepts discussed include (1) acid- and toxic-forming materials (AFM and TFM), (2) quantification procedures for AFM and TFM, (3) procedures used to identify topsoil substitutes that are {open_quotes}equal to or more suitable than{close_quotes} existing premine native soils, and (4) current interpretations of what is meant by {open_quotes}the best available material to support revegetation{close_quotes} of surface-mined areas. To support these interpretations, reference is made throughout the paper to relevant sections of the (1) Texas Coal Mining Regulations (TCMR), (2) Surface Mining Control and Reclamation Act (SMCRA), and (3) Federal regulations promulgated by the Office of Surface Mining (OSM) to implement SMCRA. The success of the Texas reclamation program, as indicated by the quality of the reclaimed soils is also discussed. This success is partly attributed to the rigorous application of the quantification concepts and parameters discussed in this paper.

  2. Evaluation of satellite soil moisture products over Norway using ground-based observations

    Science.gov (United States)

    Griesfeller, A.; Lahoz, W. A.; Jeu, R. A. M. de; Dorigo, W.; Haugen, L. E.; Svendby, T. M.; Wagner, W.

    2016-03-01

    In this study we evaluate satellite soil moisture products from the advanced SCATterometer (ASCAT) and the Advanced Microwave Scanning Radiometer - Earth Observing System (AMSR-E) over Norway using ground-based observations from the Norwegian water resources and energy directorate. The ASCAT data are produced using the change detection approach of Wagner et al. (1999), and the AMSR-E data are produced using the VUA-NASA algorithm (Owe et al., 2001, 2008). Although satellite and ground-based soil moisture data for Norway have been available for several years, hitherto, such an evaluation has not been performed. This is partly because satellite measurements of soil moisture over Norway are complicated owing to the presence of snow, ice, water bodies, orography, rocks, and a very high coastline-to-area ratio. This work extends the European areas over which satellite soil moisture is validated to the Nordic regions. Owing to the challenging conditions for soil moisture measurements over Norway, the work described in this paper provides a stringent test of the capabilities of satellite sensors to measure soil moisture remotely. We show that the satellite and in situ data agree well, with averaged correlation (R) values of 0.72 and 0.68 for ASCAT descending and ascending data vs in situ data, and 0.64 and 0.52 for AMSR-E descending and ascending data vs in situ data for the summer/autumn season (1 June-15 October), over a period of 3 years (2009-2011). This level of agreement indicates that, generally, the ASCAT and AMSR-E soil moisture products over Norway have high quality, and would be useful for various applications, including land surface monitoring, weather forecasting, hydrological modelling, and climate studies. The increasing emphasis on coupled approaches to study the earth system, including the interactions between the land surface and the atmosphere, will benefit from the availability of validated and improved soil moisture satellite datasets, including those

  3. Cultural heritage evaluation: a reappraisal of some critical concepts involved

    Directory of Open Access Journals (Sweden)

    Mihaela IACOB

    2012-12-01

    Full Text Available This study aims to build a synoptic picture of the facets of the economic category called “value”, with practicality in the tangible cultural heritage field, from the point of view of a traditionally economists-specific approach: concern for the financial sustainability of any decision. Moreover, the methods from the economics literature regarding the valences of the “cultural value” concept prove the obsoleteness of the common opinion according to which the economic approach is primarily interested in financial metrics. In as much as the ultimate goal of the scientific process is to identify the most effective cultural heritage preservation and evaluation methods, the study also reflects the public-private interference in this area.

  4. [Evaluation in the health sector: concepts and methods].

    Science.gov (United States)

    Contandriopoulos, A P; Champagne, F; Denis, J L; Avargues, M C

    2000-12-01

    The practice of evaluation has existed in one form or another for as long as one can remember and is central to all processes of learning. Today, evaluation is a popular concept grouping together multiple and diverse realities. This article aims to propose a conceptual framework for evaluation that is broad and universal enough to allow all those concerned with evaluation of health services (regardless of their disciplines and interests) to better understand each other, to perform better evaluations, and to use them in a more pertinent manner. We will begin by defining evaluation as the process which consists of making a judgement on the value of an intervention by implementing a system which can provide scientifically valid and socially legitimate information on regarding this particular intervention (or any of its components) to the different stakeholders concerned, such that they can form an opinion from their perspective on the intervention and reach a judgement which can translate into action. We define "intervention" as any organized system of action (a structure, actors and their practices, processes of action, one or many finalities and an environment) aiming to, in a given environment, during a given time period, modify the foreseeable course of a phenomenon to correct a problematic situation. An intervention can be a technique, a medication, a treatment, an organisation, a program, a policy or even a complex system like the health care system. Various interventions, regardless of their nature, can be the object of two types of evaluation. Normative evaluation is based on appreciation of each component of the intervention according to criteria and standards. This type of evaluation is defined as an activity which consists of making a judgement regarding an intervention by comparing the resources utilized and their organisation (structure); services and goods produced (process) and results obtained to criteria and standards (in other words, summaries of

  5. Evaluation of clouds and precipitation in the ECHAM5 general circulation model using CALIPSO and CloudSat satellite data

    OpenAIRE

    Nam, Christine C. W.; Quaas, Johannes

    2015-01-01

    Observations from Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) and CloudSat satellites are used to evaluate clouds and precipitation in the ECHAM5 general circulation model. Active lidar and radar instruments on board CALIPSO and CloudSat allow the vertical distribution of clouds and their optical properties to be studied on a global scale. To evaluate the clouds modeled by ECHAM5 with CALIPSO and CloudSat, the lidar and radar satellite simulators of the Cloud ...

  6. Satellite Testbed for Evaluating Cryogenic-Liquid Behavior in Microgravity

    Science.gov (United States)

    Putman, Philip Travis (Inventor)

    2017-01-01

    Provided is a testbed for conducting an experiment on a substance in a cryogenic liquid state in a microgravity environment. The testbed includes a frame with rectangular nominal dimensions, and a source section including a supply of the substance to be evaluated in the cryogenic liquid state. An experiment section includes an experiment vessel in fluid communication with the storage section to receive the substance from the storage section and condense the substance into the cryogenic liquid state. A sensor is adapted to sense a property of the substance in the cryogenic liquid state in the experiment vessel as part of the experiment. A bus section includes a controller configured to control delivery of the substance from the storage section to the experiment vessel, and receive property data indicative of the property sensed by the sensor for subsequent evaluation on Earth.

  7. Obs4MIPS: Satellite Observations for Model Evaluation

    Science.gov (United States)

    Ferraro, R.; Waliser, D. E.; Gleckler, P. J.

    2015-12-01

    This poster will review the current status of the obs4MIPs project, whose purpose is to provide a limited collection of well-established and documented datasets for comparison with Earth system models (https://www.earthsystemcog.org/projects/obs4mips/). These datasets have been reformatted to correspond with the CMIP5 model output requirements, and include technical documentation specifically targeted for their use in model output evaluation. There are currently over 50 datasets containing observations that directly correspond to CMIP5 model output variables. We will review recent additions to the obs4MIPs collection, and provide updated download statistics. We will also provide an update on changes to submission and documentation guidelines, the work of the WCRP Data Advisory Council (WDAC) Observations for Model Evaluation Task Team, and engagement with the CMIP6 MIP experiments.

  8. Satellite communication performance evaluation: Computational techniques based on moments

    Science.gov (United States)

    Omura, J. K.; Simon, M. K.

    1980-01-01

    Computational techniques that efficiently compute bit error probabilities when only moments of the various interference random variables are available are presented. The approach taken is a generalization of the well known Gauss-Quadrature rules used for numerically evaluating single or multiple integrals. In what follows, basic algorithms are developed. Some of its properties and generalizations are shown and its many potential applications are described. Some typical interference scenarios for which the results are particularly applicable include: intentional jamming, adjacent and cochannel interferences; radar pulses (RFI); multipath; and intersymbol interference. While the examples presented stress evaluation of bit error probilities in uncoded digital communication systems, the moment techniques can also be applied to the evaluation of other parameters, such as computational cutoff rate under both normal and mismatched receiver cases in coded systems. Another important application is the determination of the probability distributions of the output of a discrete time dynamical system. This type of model occurs widely in control systems, queueing systems, and synchronization systems (e.g., discrete phase locked loops).

  9. Evaluation of Students' Energy Conception in Environmental Science

    Science.gov (United States)

    Park, Mihwa; Johnson, Joseph A.

    2016-01-01

    While significant research has been conducted on students' conceptions of energy, alternative conceptions of energy have not been actively explored in the area of environmental science. The purpose of this study is to examine students' alternative conceptions in the environmental science discipline through the analysis of responses of first year…

  10. Satellite-aided evaluation of population exposure to air pollution

    Science.gov (United States)

    Todd, W. J.; George, A. J., Jr.; Bryant, N. A.

    1979-01-01

    The evaluation of population exposure to air pollution through the computer processing of Landsat digital land use data, along with total suspended particulate estimates and population data by census tracts, is demonstrated. Digital image processing was employed to analyze simultaneously data from Landsat MSS bands 4 through 7 in order to extract land use and land cover information. The three data sets were spatially registered in a digital format, compatible with integrated computer processing, and cross-tabulated. A map illustrating relative air quality by 2-sq km cells for the residential population in the Portland, Oregon area is obtained.

  11. LOOPUS Mob-D: System concept for a public mobile satellite system providing integrated digital services for the Northern Hemisphere from an elliptical orbit

    Science.gov (United States)

    Kuhlen, H.; Horn, P.

    1990-08-01

    A new concept for a satellite based public mobile communications system LOOPUS Mob-D is introduced where most of the 'classical' problems in mobile satellite systems are approached in a different way. The LOOPUS system will offer a total capacity of 6000 high rate channel in three service areas (Europe, Asia, and North America) covering the entire Northern Hemisphere with a set of group special mobile (GSM) compatible mobile services eventually providing the 'office in the car'. Special characteristics of the LOOPUS orbit and the communications network architecture are highlighted.

  12. Evaluating the Cloud Cover Forecast of NCEP Global Forecast System with Satellite Observation

    CERN Document Server

    Ye, Quanzhi

    2011-01-01

    To assess the quality of daily cloud cover forecast generated by the operational global numeric model, the NCEP Global Forecast System (GFS), we compose a large sample with outputs from GFS model and satellite observations from the International Satellite Cloud Climatology Project (ISCCP) in the period of July 2004 to June 2008, to conduct a quantitative and systematic assessment of the performance of a cloud model that covers a relatively long range of time, basic cloud types, and in a global view. The evaluation has revealed the goodness of the model forecast, which further illustrates our completeness on understanding cloud generation mechanism. To quantity the result, we found a remarkably high correlation between the model forecasts and the satellite observations over the entire globe, with mean forecast error less than 15% in most areas. Considering a forecast within 30% difference to the observation to be a "good" one, we find that the probability for the GFS model to make good forecasts varies between...

  13. Environmental evaluation of the forest of Mt. Fuji, based on multiple satellite data

    Energy Technology Data Exchange (ETDEWEB)

    Shiosaka, K.; Konta, F.; Nishikawa, H. (The Inst. of Regional Environ. Planning, Shizuoka (Japan) Shizuoka Univ., Shizuoka (Japan) Nippon Univ., Narashino (Japan))

    1994-03-01

    Evaluation of environmental roles of the forest of Mt. Fuji and estimation of deposition of sulfur dioxide on the leaves of Japanese cypress (Chamaecyparis obtusa) were done based on satellite data. The evaluation suggests that artificial Japanese cypress forests, which occupy the largest area among vegetations of Mt. Fuji, have problems concerning environmental role of storing of soil water, and that the result of the estimation indicates an uneven distribution of sulfur dioxide deposition.

  14. Environmental evaluation of the forest of MT Fuji, based on multiple satellite data

    Science.gov (United States)

    Shiosaka, K.; Konta, F.; Nishikawa, H.

    1994-03-01

    Evaluation of environmental roles of the forest of Mt. Fuji and estimation of deposition of sulfur dioxide on the leaves of Japanese cypress (Chamaecyparis obtusa) weere done based on satellite data. The evaluation suggests that artificial Japanese cypress forests, which occupy the largest area among vegetations of Mt. Fuji have problems concerning environmental role of storing of soil water, and that the result of the estimation indicates an uneven distribution of sulfur dioxide deposition.

  15. Evaluation of spacecraft technology programs (effects on communication satellite business ventures), volume 1

    Science.gov (United States)

    Greenburg, J. S.; Gaelick, C.; Kaplan, M.; Fishman, J.; Hopkins, C.

    1985-01-01

    Commercial organizations as well as government agencies invest in spacecraft (S/C) technology programs that are aimed at increasing the performance of communications satellites. The value of these programs must be measured in terms of their impacts on the financial performane of the business ventures that may ultimately utilize the communications satellites. An economic evaluation and planning capability was developed and used to assess the impact of NASA on-orbit propulsion and space power programs on typical fixed satellite service (FSS) and direct broadcast service (DBS) communications satellite business ventures. Typical FSS and DBS spin and three-axis stabilized spacecraft were configured in the absence of NASA technology programs. These spacecraft were reconfigured taking into account the anticipated results of NASA specified on-orbit propulsion and space power programs. In general, the NASA technology programs resulted in spacecraft with increased capability. The developed methodology for assessing the value of spacecraft technology programs in terms of their impact on the financial performance of communication satellite business ventures is described. Results of the assessment of NASA specified on-orbit propulsion and space power technology programs are presented for typical FSS and DBS business ventures.

  16. Evaluation of multi-satellite rainfall products over India during monsoon

    Science.gov (United States)

    Mitra, Ashis K.; Prakash, Satya; Pai, D. S.; Srivastava, A. K.

    2016-05-01

    Simulation and prediction of Indian monsoon rainfall at scales from days-to-season is a challenging task for numerical modelling community worldwide. Gridded estimates of daily rainfall data are required for both land and oceanic regions for model validation, process studies and in turn for model development. Due to recent developments in satellite meteorology, it has become possible to produce realistic near real-time gridded rainfall datasets at operational basis by combining satellite estimates with rain gauge values and other available in-situ observations. Microwave and space based radar based estimates of rainfall has revolutionised the preparation of rainfall datasets especially for tropics. However, a variety of multi-satellite products are available over Indian monsoon region from a variety of sources. Popular products like TRMM TMPA3B42 (RT and V7), GsMaP, CPC/RFE, GPCP and GPM are available to end users in various space/time scales for applications and model validation. In this study, we show the representation and skill of monsoon rainfall from a variety of multi-satellite products over the Indian region. The bias and skill of multi-satellite rainfall are evaluated against gauge based observations. It was found that the TRMM based TMPA was one of the best dataset for Indian monsoon region. Attempt is made to compare the latest GPM based data with other products. The GPM based rainfall product is seen to be superior compared to TRMM.

  17. Concept of REACH and impact on evaluation of chemicals.

    Science.gov (United States)

    Foth, H; Hayes, Aw

    2008-01-01

    Industrial chemicals have been in use for many decades and new products are regularly invented and introduced to the market. Also for decades, many different chemical laws have been introduced to regulate safe handling of chemicals in different use patterns. The patchwork of current regulation in the European Union is to be replaced by the new regulation on industrial chemical control, REACH. REACH stands for registration, evaluation, and authorization of chemicals. REACH entered force on June 1, 2007. REACH aims to overcome limitations in testing requirements of former regulation on industrial chemicals to enhance competitiveness and innovation with regard to manufacture safer substances and to promote the development of alternative testing methods. A main task of REACH is to address data gaps regarding the properties and uses of industrial chemicals. Producers, importers, and downstream users will have to compile and communicate standard information for all chemicals. Information sets to be prepared include safety data sheets (SDS), chemical safety reports (CSR), and chemical safety assessments (CSA). These are designed to guarantee adequate handling in the production chain, in transport and in use and to prevent the substances from being released to and distributed within the environment. Another important aim is to identify the most harmful chemicals and to set incentives to substitute them with safer alternatives. On one hand, REACH will have substantial impact on the basic understanding of the evaluation of chemicals. However, the toxicological sciences can also substantially influence the workability of REACH that supports the transformation of data to the information required to understand and manage acceptable and non acceptable risks in the use of industrial chemicals. The REACH regulation has been laid down in the main document and 17 Annexes of more than 849 pages. Even bigger technical guidance documents will follow and will inform about the rules for

  18. EVALUATION OF POWER SPECTRAL DENSITY OF PASSIVE INTERMODULATION DISTORTION IN HIGH-POWER COMMUNICATION SATELLITE SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    Zhang Shiquan; Ge Debiao

    2005-01-01

    In order to analyze the deleterious effects of Passive InterModulation (PIM) on high power communication satellite systems, the basic concept of PIM is introduced, and an equation for the power spectral density of the n-th order PIM distortion insuch systems is derived by applying flat signal-power spectrum assumption and Fourier transform method. It is indicated that PIM level generally decreases with order and the lowest frequency receive channel in the receive band is the channel of most affected by PIM interference.

  19. Aerosol indirect effects -- general circulation model intercomparison and evaluation with satellite data

    Energy Technology Data Exchange (ETDEWEB)

    Quaas, Johannes; Ming, Yi; Menon, Surabi; Takemura, Toshihiko; Wang, Minghuai; Penner, Joyce E.; Gettelman, Andrew; Lohmann, Ulrike; Bellouin, Nicolas; Boucher, Olivier; Sayer, Andrew M.; Thomas, Gareth E.; McComiskey, Allison; Feingold, Graham; Hoose, Corinna; Kristjansson, Jon Egill; Liu, Xiaohong; Balkanski, Yves; Donner, Leo J.; Ginoux, Paul A.; Stier, Philip; Feichter, Johann; Sednev, Igor; Bauer, Susanne E.; Koch, Dorothy; Grainger, Roy G.; Kirkevag, Alf; Iversen, Trond; Seland, Oyvind; Easter, Richard; Ghan, Steven J.; Rasch, Philip J.; Morrison, Hugh; Lamarque, Jean-Francois; Iacono, Michael J.; Kinne, Stefan; Schulz, Michael

    2009-04-10

    Aerosol indirect effects continue to constitute one of the most important uncertainties for anthropogenic climate perturbations. Within the international AEROCOM initiative, the representation of aerosol-cloud-radiation interactions in ten different general circulation models (GCMs) is evaluated using three satellite datasets. The focus is on stratiform liquid water clouds since most GCMs do not include ice nucleation effects, and none of the model explicitly parameterizes aerosol effects on convective clouds. We compute statistical relationships between aerosol optical depth (Ta) and various cloud and radiation quantities in a manner that is consistent between the models and the satellite data. It is found that the model-simulated influence of aerosols on cloud droplet number concentration (Nd) compares relatively well to the satellite data at least over the ocean. The relationship between Ta and liquid water path is simulated much too strongly by the models. It is shown that this is partly related to the representation of the second aerosol indirect effect in terms of autoconversion. A positive relationship between total cloud fraction (fcld) and Ta as found in the satellite data is simulated by the majority of the models, albeit less strongly than that in the satellite data in most of them. In a discussion of the hypotheses proposed in the literature to explain the satellite-derived strong fcld - Ta relationship, our results indicate that none can be identified as unique explanation. Relationships similar to the ones found in satellite data between Ta and cloud top temperature or outgoing long-wave radiation (OLR) are simulated by only a few GCMs. The GCMs that simulate a negative OLR - Ta relationship show a strong positive correlation between Ta and fcld The short-wave total aerosol radiative forcing as simulated by the GCMs is strongly influenced by the simulated anthropogenic fraction of Ta, and parameterisation assumptions such as a lower bound on Nd

  20. Self-concept evaluation and migraine without aura in childhood

    Directory of Open Access Journals (Sweden)

    Esposito M

    2013-08-01

    Full Text Available Maria Esposito,1 Beatrice Gallai,2 Lucia Parisi,3 Laura Castaldo,1 Rosa Marotta,4 Serena Marianna Lavano,4 Giovanni Mazzotta,5 Michele Roccella,3 Marco Carotenuto11Center for Childhood Headache, Clinic of Child and Adolescent Neuropsychiatry, Department of Mental Health, Physical and Preventive Medicine, Second University of Naples, Naples, Italy; 2Unit of Child and Adolescent Neuropsychiatry, University of Perugia, Perugia, Italy; 3Child Neuropsychiatry, Department of Psychology, University of Palermo, Palermo, Italy; 4Department of Psychiatry, "Magna Graecia" University of Catanzaro, Catanzaro, Italy; 5Unit of Child and Adolescent Neuropsychiatry, AUSL Umbria 2, Terni, ItalyIntroduction: Self-esteem is related to the broadly understood concept of self-schemas and is a crucial mechanism for a correct psychological development in children and adolescents. The impact of the many psychological difficulties linked to the migraine without aura (MoA and recurrent headache attacks, such as anger and separation anxiety, on self-esteem has not yet been well investigated. The aims of the present study were to assess self-esteem levels in an objective way and to verify their possible relationship and correlation with the frequency and intensity of migraine attacks, in a population of children and adolescents affected by MoA.Methods: The study population was comprised of 185 children (88 males [M], 97 females [F] aged between 6 and 12 years (mean 9.04 ± 2.41 years referred consecutively for MoA to the Center for Childhood Headache, Clinic of Child and Adolescent Neuropsychiatry, Second University of Naples and of 203 healthy controls (95 M, 108 F with mean age 9.16 ± 2.37 years, recruited from schools in Campania. The monthly headache frequency and the mean headache duration were assessed from daily headache diaries kept by all the children, and MoA intensity was assessed on a VAS (visual analog scale. To further evaluate their level of self-concept, all

  1. Evaluation of satellite based indices for primary production estimates in a sparse savanna in the Sudan

    Directory of Open Access Journals (Sweden)

    M. Sjöström

    2008-07-01

    Full Text Available One of the more frequently applied methods for integrating controls on primary production through satellite data is the Light Use Efficiency (LUE approach. Satellite indices such as the Enhanced Vegetation Index (EVI and the Shortwave Infrared Water Stress Index (SIWSI have previously shown promise as predictors of primary production in several different environments. In this study, we evaluate EVI and SIWSI derived from the Moderate Resolution Imaging Spectroradiometer (MODIS satellite sensor against in-situ measurements from central Sudan in order to asses their applicability in LUE-based primary production modelling within a water limited environment. Results show a strong correlation between EVI against gross primary production (GPP, demonstrating the significance of EVI for deriving information on primary production with relatively high accuracy at similar areas. Evaluation of SIWSI however, reveal that the fraction of vegetation apparently is to low for the index to provide accurate information on canopy water content, indicating that the use of SIWSI as a predictor of water stress in satellite data-driven primary production modelling in similar semi-arid ecosystems is limited.

  2. Evaluation the effect of energetic particles in solar flares on satellite's life time

    Science.gov (United States)

    Bagheri, Z.; Davoudifar, P.

    2016-09-01

    As the satellites have a multiple role in the humans' life, their damages and therefore logical failures of their segment causes problems and lots of expenses. So evaluating different types of failures in their segments has a crustal role. Solar particles are one of the most important reasons of segment damages (hard and soft) during a solar event or in usual times. During a solar event these particle may cause extensive damages which are even permanent (hard errors). To avoid these effects and design shielding mediums, we need to know SEP (solar energetic particles) flux and MTTF (mean time between two failures) of segments. In the present work, we calculated SEP flux witch collide the satellite in common times, in different altitudes. OMERE software was used to determine the coordinates and specifications of a satellite which in simulations has been launched to space. Then we considered a common electronic computer part and calculated MTTF for it. In the same way the SEP fluxes were calculated during different solar flares of different solar cycles and MTFFs were evaluated during occurring of solar flares. Thus a relation between solar flare energy and life time of the satellite electronic part (hours) was obtained.

  3. Evaluation of Land Surface Temperature Operationally Retrieved from Korean Geostationary Satellite (COMS Data

    Directory of Open Access Journals (Sweden)

    A-Ra Cho

    2013-08-01

    Full Text Available We evaluated the precision of land surface temperature (LST operationally retrieved from the Korean multipurpose geostationary satellite, Communication, Ocean and Meteorological Satellite (COMS. The split-window (SW-type retrieval algorithm was developed through radiative transfer model simulations under various atmospheric profiles, satellite zenith angles, surface emissivity values and surface lapse rate conditions using Moderate Resolution Atmospheric Transmission version 4 (MODTRAN4. The estimation capabilities of the COMS SW (CSW LST algorithm were evaluated for various impacting factors, and the retrieval accuracy of COMS LST data was evaluated with collocated Moderate Resolution Imaging Spectroradiometer (MODIS LST data. The surface emissivity values for two SW channels were generated using a vegetation cover method. The CSW algorithm estimated the LST distribution reasonably well (averaged bias = 0.00 K, Root Mean Square Error (RMSE = 1.41 K, correlation coefficient = 0.99; however, the estimation capabilities of the CSW algorithm were significantly impacted by large brightness temperature differences and surface lapse rates. The CSW algorithm reproduced spatiotemporal variations of LST comparing well to MODIS LST data, irrespective of what month or time of day the data were collected from. The one-year evaluation results with MODIS LST data showed that the annual mean bias, RMSE and correlation coefficient for the CSW algorithm were −1.009 K, 2.613 K and 0.988, respectively.

  4. Systematic evaluation of satellite remote sensing for identifying uranium mines and mills.

    Energy Technology Data Exchange (ETDEWEB)

    Blair, Dianna Sue; Stork, Christopher Lyle; Smartt, Heidi Anne; Smith, Jody Lynn

    2006-01-01

    In this report, we systematically evaluate the ability of current-generation, satellite-based spectroscopic sensors to distinguish uranium mines and mills from other mineral mining and milling operations. We perform this systematic evaluation by (1) outlining the remote, spectroscopic signal generation process, (2) documenting the capabilities of current commercial satellite systems, (3) systematically comparing the uranium mining and milling process to other mineral mining and milling operations, and (4) identifying the most promising observables associated with uranium mining and milling that can be identified using satellite remote sensing. The Ranger uranium mine and mill in Australia serves as a case study where we apply and test the techniques developed in this systematic analysis. Based on literature research of mineral mining and milling practices, we develop a decision tree which utilizes the information contained in one or more observables to determine whether uranium is possibly being mined and/or milled at a given site. Promising observables associated with uranium mining and milling at the Ranger site included in the decision tree are uranium ore, sulfur, the uranium pregnant leach liquor, ammonia, and uranyl compounds and sulfate ion disposed of in the tailings pond. Based on the size, concentration, and spectral characteristics of these promising observables, we then determine whether these observables can be identified using current commercial satellite systems, namely Hyperion, ASTER, and Quickbird. We conclude that the only promising observables at Ranger that can be uniquely identified using a current commercial satellite system (notably Hyperion) are magnesium chlorite in the open pit mine and the sulfur stockpile. Based on the identified magnesium chlorite and sulfur observables, the decision tree narrows the possible mineral candidates at Ranger to uranium, copper, zinc, manganese, vanadium, the rare earths, and phosphorus, all of which are

  5. Climate Model Diagnostic and Evaluation: With a Focus on Satellite Observations

    Science.gov (United States)

    Waliser, Duane

    2011-01-01

    Each year, we host a summer school that brings together the next generation of climate scientists - about 30 graduate students and postdocs from around the world - to engage with premier climate scientists from the Jet Propulsion Laboratory and elsewhere. Our yearly summer school focuses on topics on the leading edge of climate science research. Our inaugural summer school, held in 2011, was on the topic of "Using Satellite Observations to Advance Climate Models," and enabled students to explore how satellite observations can be used to evaluate and improve climate models. Speakers included climate experts from both NASA and the National Oceanic and Atmospheric Administration (NOAA), who provided updates on climate model diagnostics and evaluation and remote sensing of the planet. Details of the next summer school will be posted here in due course.

  6. The Expert Infantryman Squad and Platoon Evaluation (EISPE) I Concept: Evaluations and Observations

    Science.gov (United States)

    1977-12-01

    field tesot c the MISPI concept. Thix chart includes bh dsa,•-p! ; infom -ation about the platoon members and the results of the scoring•at AiSPI...sufficiently definitive that scale ratings rather than a checkoff system could be used to score individuals on each test point. These same evaluator personnel...especially i-c 5.terns as challenging , sentry behaviors, water purification, and wrutp *Jlspcsa.1, the questiorA is whether to include them In the

  7. Evaluating satellite-derived long-term historical precipitation datasets for drought monitoring in Chile

    Science.gov (United States)

    Zambrano, Francisco; Wardlow, Brian; Tadesse, Tsegaye

    2016-10-01

    Precipitation is a key parameter for the study of climate change and variability and the detection and monitoring of natural disaster such as drought. Precipitation datasets that accurately capture the amount and spatial variability of rainfall is critical for drought monitoring and a wide range of other climate applications. This is challenging in many parts of the world, which often have a limited number of weather stations and/or historical data records. Satellite-derived precipitation products offer a viable alternative with several remotely sensed precipitation datasets now available with long historical data records (+30 years), which include the Climate Hazards Group InfraRed Precipitation with Station (CHIRPS) and Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Climate Data Record (PERSIANN-CDR) datasets. This study presents a comparative analysis of three historical satellite-based precipitation datasets that include Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) 3B43 version 7 (1998-2015), PERSIANN-CDR (1983-2015) and CHIRPS 2.0 (1981-2015) over Chile to assess their performance across the country and evaluate their applicability for agricultural drought evaluation when used in the calculation of commonly used drought indicator as the Standardized Precipitation Index (SPI). In this analysis, 278 weather stations of in-situ rainfall measurements across Chile were initially compared to the satellite-based precipitation estimates. The study area (Chile) was divided into five latitudinal zones: North, North-Central, Central, South-Central and South to determine if there were a regional difference among these satellite-based estimates. Nine statistics were used to evaluate the performance of satellite products to estimate the amount and spatial distribution of historical rainfall across Chile. Hierarchical cluster analysis, k-means and singular value decomposition were used to

  8. Applications Technology Satellite ATS-6 experiment checkout and continuing spacecraft evaluation report

    Science.gov (United States)

    Moore, W.; Prensky, W. (Editor)

    1974-01-01

    The activities of the ATS-6 spacecraft are reviewed. The following subsystems and experiments are summarized: (1) radio beacon experiments; (2) spacecraft attitude precision pointing and slewing adaptive control experiment; (3) satellite instruction television experiment; (4) thermal control subsystem; (5) spacecraft propulsion subsystem; (6) telemetry and control subsystem; (7) millimeter wave experiment; and (8) communications subsystem. The results of performance evaluation of its subsystems and experiments are presented.

  9. Performance Evaluation of Machine Learning Algorithms for Urban Pattern Recognition from Multi-spectral Satellite Images

    OpenAIRE

    Marc Wieland; Massimiliano Pittore

    2014-01-01

    In this study, a classification and performance evaluation framework for the recognition of urban patterns in medium (Landsat ETM, TM and MSS) and very high resolution (WorldView-2, Quickbird, Ikonos) multi-spectral satellite images is presented. The study aims at exploring the potential of machine learning algorithms in the context of an object-based image analysis and to thoroughly test the algorithm’s performance under varying conditions to optimize their usage for urban pattern recognitio...

  10. The Lassen Astrobiology Intern Program - Concept, Implementation and Evaluation

    Science.gov (United States)

    Des Marais, D. J.; Dueck, S. L.; Davis, H. B.; Parenteau, M. N.; Kubo, M. D.

    2014-12-01

    The program goal was to provide a hands-on astrobiology learning experience to high school students by introducing astrobiology and providing opportunities to conduct field and lab research with NASA scientists. The program sought to increase interest in interdisciplinary science, technology, engineering, math and related careers. Lassen Volcanic National Park (LVNP), Red Bluff High School and the Ames Team of the NASA Astrobiology Institute led the program. LVNP was selected because it shares aspects of volcanism with Mars and it hosts thermal springs with microbial mat communities. Students documented volcanic deposits, springs and microbial mats. They analyzed waters and sampled rocks, water and microorganisms. They cultured microorganisms and studied chemical reactions between rocks and simulated spring waters. Each student prepared a report to present data and discuss relationships between volcanic rocks and gases, spring waters and microbial mats. At a "graduation" event the students presented their findings to the Red Bluff community. They visited Ames Research Center to tour the facilities and learn about science and technology careers. To evaluate program impact, surveys were given to students after lectures, labs, fieldwork and discussions with Ames scientists. Students' work was scored using rubrics (labs, progress reports, final report, presentation). Students took pre/post tests on core astrobiology concepts. Parents, teachers, rangers, Ames staff and students completed end-of-year surveys on program impact. Several outcomes were documented. Students had a unique and highly valued learning experience with NASA scientists. They understood what scientists do through authentic scientific work, and what scientists are like as individuals. Students became knowledgeable about astrobiology and how it can be pursued in the lab and in the field. The students' interest increased markedly in astrobiology, interdisciplinary studies and science generally.

  11. Evaluation and comparison of space solar power concepts

    Energy Technology Data Exchange (ETDEWEB)

    Feingold, Harvey [Science Applications International Corp., Schaumburg, IL (United States); Carrington, Connie [NASA Marshall Space Flight Center, Flight Projects Directorate, Huntsville, AL (United States)

    2003-11-01

    The SSP Exploratory Research and Technology (SERT) program undertaken by NASA in the 1999-2000 timeframe was the third in a recent series of NASA sponsored studies of Space Solar Power (SSP) that began with the 1995 SSP 'Fresh Look' Study, and was followed by the SSP Concept Definition Study in 1998. In all three studies, a major focus has been on identifying system concepts, architectures and technologies that may ultimately produce a practical, economically viable source of electrical power to help satisfy the world's growing energy needs. As part of the SERT program, members of the study team developed several new and innovative SSP concepts that sprung from a desire to address the problem areas of previous system concepts with new technology and system solutions. In the previous SSP studies it has been shown that systems analyses and sensitivity studies are key to understanding the merits of different system concepts and technologies, particularly with respect to their impact on the mass and cost of space hardware and their ultimate economic impact on the cost of SSP-produced electricity. Enabled by analytical models and tools developed over the series of SSP studies, seven different system concepts as well as different technology choices within these concepts were quantitatively compared with one another on the basis of the mass and cost metrics suggested above. Accompanying sensitivity studies have permitted examination of how variations in the projected capabilities of different technologies could affect conclusions drawn from these analyses. This paper summarizes the results of these analytical efforts and from those results, identifies the most promising SSP concepts, including their key technologies and their comparative advantages and disadvantages. (Author)

  12. Evaluation and comparison of space solar power concepts

    Science.gov (United States)

    Feingold, Harvey; Carrington, Connie

    2003-08-01

    The SSP Exploratory Research and Technology (SERT) program undertaken by NASA in the 1999-2000 timeframe was the third in a recent series of NASA sponsored studies of Space Solar Power (SSP) that began with the 1995 SSP "Fresh Look" Study, and was followed by the SSP Concept Definition Study in 1998. In all three studies, a major focus has been on identifying system concepts, architectures and technologies that may ultimately produce a practical, economically viable source of electrical power to help satisfy the world's growing energy needs. As part of the SERT program, members of the study team developed several new and innovative SSP concepts that sprung from a desire to address the problem areas of previous system concepts with new technology and system solutions. In the previous SSP studies it has been shown that systems analyses and sensitivity studies are key to understanding the merits of different system concepts and technologies, particularly with respect to their impact on the mass and cost of space hardware and their ultimate economic impact on the cost of SSP-produced electricity. Enabled by analytical models and tools developed over the series of SSP studies, seven different system concepts as well as different technology choices within these concepts were quantitatively compared with one another on the basis of the mass and cost metrics suggested above. Accompanying sensitivity studies have permitted examination of how variations in the projected capabilities of different technologies could affect conclusions drawn from these analyses. This paper summarizes the results of these analytical efforts and from those results, identifies the most promising SSP concepts, including their key technologies and their comparative advantages and disadvantages.

  13. Selection of the best initial orbital elements of satellite based on fuzzy integration evaluation method

    Institute of Scientific and Technical Information of China (English)

    Yang Yong'an; Zhang Hongwei; Feng Zuren; Luo Yongjin

    2006-01-01

    The fuzzy integration evaluation method (FIEM) is studied in order to select the best orbital elements from the multi-group initial orbits determined by a satellite TT&C (Tracking, Telemetry and Control) center with all kinds of data sources. By employing FIEM together with the experience of TT&C experts, the index system to evaluate the selection of the best initial orbits is established after the data sources and orbit determination theories are studied. Besides, the concrete steps in employing the method are presented. Moreover, by taking the objects to be evaluated as evaluation experts, the problem of how to generate evaluation matrices is solved. Through practical application, the method to select the best initial orbital elements has been proved to be flexible and effective. The originality of the method is to find a new evaluation criterion (comparing the actually tracked orbits) replacing the traditional one (comparing the nominal orbits) for selecting the best orbital elements.

  14. EPSAT-SG: a satellite method for precipitation estimation; its concepts and implementation for the AMMA experiment

    Directory of Open Access Journals (Sweden)

    J. C. Bergès

    2010-01-01

    Full Text Available This paper presents a new rainfall estimation method, EPSAT-SG which is a frame for method design. The first implementation has been carried out to meet the requirement of the AMMA database on a West African domain. The rainfall estimation relies on two intermediate products: a rainfall probability and a rainfall potential intensity. The first one is computed from MSG/SEVIRI by a feed forward neural network. First evaluation results show better properties than direct precipitation intensity assessment by geostationary satellite infra-red sensors. The second product can be interpreted as a conditional rainfall intensity and, in the described implementation, it is extracted from GPCP-1dd. Various implementation options are discussed and comparison of this embedded product with 3B42 estimates demonstrates the importance of properly managing the temporal discontinuity. The resulting accumulated rainfall field can be presented as a GPCP downscaling. A validation based on ground data supplied by AGRHYMET (Niamey indicates that the estimation error has been reduced in this process. The described method could be easily adapted to other geographical area and operational environment.

  15. Evaluation of satellite-based precipitation estimates in winter season using an object-based approach

    Science.gov (United States)

    Li, J.; Hsu, K.; AghaKouchak, A.; Sorooshian, S.

    2012-12-01

    Verification has become an integral component of satellite precipitation algorithms and products. A number of object-based verification methods have been proposed to provide diagnostic information regarding the precipitation products' ability to capture the spatial pattern, intensity, and placement of precipitation. However, most object-based methods are not capable of investigating precipitation objects at the storm-scale. In this study, an image processing approach known as watershed segmentation was adopted to detect the storm-scale rainfall objects. Then, a fuzzy logic-based technique was utilized to diagnose and analyze storm-scale object attributes, including centroid distance, area ratio, intersection area ratio and orientation angle difference. Three verification metrics (i.e., false alarm ratio, missing ratio and overall membership score) were generated for validation and verification. Three satellite-based precipitation products, including PERSIANN, CMORPH, 3B42RT, were evaluated against NOAA stage IV MPE multi-sensor composite rain analysis at 0.25° by 0.25° on a daily scale in the winter season of 2010 over the contiguous United States. Winter season is dominated by frontal systems which usually have larger area coverage. All three products and the stage IV observation tend to find large size storm objects. With respect to the evaluation attributes, PERSIANN tends to obtain larger area ratio and consequently has larger centroid distance to the stage IV observations, while 3B42RT are found to be closer to the stage IV for the object size. All evaluation products give small orientation angle differences but vary significantly for the missing ratio and false alarm ratio. This implies that satellite estimates can fail to detect storms in winter. The overall membership scores are close for all three different products which indicate that all three satellite-based precipitation products perform well for capturing the spatial and geometric characteristics of

  16. Evaluation of Satellite Rainfall Products over NASA's Iowa Flood Studies (IFloodS) Domain

    Science.gov (United States)

    ElSaadani, Mohamed; Quintero, Felipe; Krajewski, Witold F.; Goska, Radoslaw; Seo, Bongchul

    2014-05-01

    Iowa Flood Studies (IFloodS) is a NASA Global Precipitation Measurement (GPM) Mission to provide better understanding of the strengths and limitations of satellite products in the context of hydrologic applications. IFloodS took place in the central to north eastern part of Iowa in Midwestern United States during the months of April-June, 2013. Quantifying the physical characteristics, space/time variability and assessing satellite rainfall retrieval uncertainties at instantaneous to daily time scales are of the main objectives of IFloodS field experiment beside assessing hydrologic predictive skills as a function of space/time scales and discerning the relative roles of rainfall quantities in flood genesis. The errors of rainfall estimation of three satellite rainfall products (TRMM's TMPA 3B42 V7, CPC's CMORPH and CHRS at UCI's PERSIANN) have been characterized in space and time using NCEP Stage IV radar-rainfall product as a benchmark for comparison. The satellite rainfall products used in this study represent 3 hourly, quarter degree, rainfall accumulation. The benchmark rainfall accumulation has an hourly, four kilometers, resolutions in time and space respectively. We also investigate the adequacy of satellite rainfall products as inputs for hydrological modeling. To this end, these products were used as forcing for the Iowa Flood Center (IFC) hydrological model and produced discharge simulations in a high-resolution drainage network. The IFC hydrological model has been validated using radar rainfall product and thus, the hydrological outputs becomes the reference of comparison for the other rainfall products. We evaluated the hydrological performance of the rainfall products at different spatial scales, ranging from 2 to 14,000 square miles using stream discharge information from USGS gauges network. We discuss the adequacy of the rainfall products for flood forecasting at different spatial scales.

  17. An Evaluation of Satellite Retrievals of Snowfall in Regions of Complex Terrain

    Science.gov (United States)

    Reed, K. A.; Nesbitt, S. W.; Kulie, M.; L'Ecuyer, T. S.; Wood, N.

    2013-12-01

    Snowfall in regions of complex terrain plays an important role in the global hydrologic cycle, and can have major physical and social implications ranging from water resource management, to flash flooding, to climate change impacts. Due to the diversity of impacts that can result from snowfall, the ability to directly observe and measure snowfall in real-time is of great importance. However, the physical limitations of ground-based radars particularly in complex terrain and the lack of spatially complete measurement networks in mountainous regions make high-resolution ground-based snowfall observations a challenging task. Spaceborne satellite retrievals of snowfall such as those that will be made possible by the Global Precipitation Measurement (GPM) mission offer the ability to make high spatial and temporal resolution measurements that are otherwise not possible using traditional ground-based methods. This study seeks to investigate the skill level of current spaceborne snowfall products over the complex terrain of the Rocky Mountains in the western United States. Satellite derived snowfall products from measurements obtained via instruments including the CloudSat Cloud Profiling Radar (CPR), EOS Aqua Advanced Microwave Scanning Radiometer for EOS (AMSR-E), and GCOM-W1 Advanced Microwave Scanning Radiometer 2 (AMSR2) are evaluated using ground-based observations such as the Natural Resources Conservation Service Snow Telemetry (SNOTEL) data and the NCEP Stage IV data. Satellite derived snowfall variables including snowfall rate and snow water equivalent are compared to ground-based observations to determine the overall accuracy and skill level of current satellite derived snowfall products in the region of interest. An analysis is also done to determine how the accuracy and skill level change based on varying snowfall regimes such as light, moderate, and heavy snowfall events. The knowledge gained will be used to determine how satellite derived snowfall

  18. BeiDou inter-satellite-type bias evaluation and calibration for mixed receiver attitude determination

    NARCIS (Netherlands)

    Nadarajah, N.; Teunissen, P.J.G.; Raziq, N.

    2013-01-01

    The Chinese BeiDou system (BDS), having different types of satellites, is an important addition to the ever growing system of Global Navigation Satellite Systems (GNSS). It consists of Geostationary Earth Orbit (GEO) satellites, Inclined Geosynchronous Satellite Orbit (IGSO) satellites and Medium

  19. BeiDou inter-satellite-type bias evaluation and calibration for mixed receiver attitude determination

    NARCIS (Netherlands)

    Nadarajah, N.; Teunissen, P.J.G.; Raziq, N.

    2013-01-01

    The Chinese BeiDou system (BDS), having different types of satellites, is an important addition to the ever growing system of Global Navigation Satellite Systems (GNSS). It consists of Geostationary Earth Orbit (GEO) satellites, Inclined Geosynchronous Satellite Orbit (IGSO) satellites and Medium Ea

  20. HY-2A satellite altimetric data evaluation in the Arctic ocean

    DEFF Research Database (Denmark)

    Cheng, Yongcun; Andersen, Ole Baltazar

    2014-01-01

    HY-2A (‘HaiYang’ denotes Ocean) was launched in August 2011. It payloads Ku and C bands radar altimeters with repeat cycles of 14 days (for three years) and 168 days. In the present study, we preliminary evaluate the HY-2 satellite altimetric data against SARAL/AltiKa and CryoSat-2 data in the Ar......HY-2A (‘HaiYang’ denotes Ocean) was launched in August 2011. It payloads Ku and C bands radar altimeters with repeat cycles of 14 days (for three years) and 168 days. In the present study, we preliminary evaluate the HY-2 satellite altimetric data against SARAL/AltiKa and CryoSat-2 data...... in the Arctic Ocean. The results demonstrates that the HY-2 data shows higher standard variation and mean sea level than AltiKa and CryoSat-2 data during HY-2 cycle 49 (20130803 and 20130817) with more available sea level measurements than CryoSat-2 satellite altimetry. Moreover, consistent sea level variation...

  1. Design and Evaluation of 10-Gbps Inter-satellite Optical Wireless Communication Link for Improved Performance

    Science.gov (United States)

    Gupta, Amit; Nagpal, Shaina

    2017-05-01

    Inter-satellite optical wireless communication (IsOWC) systems can be chosen over existing microwave satellite systems for deploying in space in the future due to their high bandwidth, small size, light weight, low power and low cost. However, the IsOWC system suffers from various attenuations due to weather conditions, turbulence or scintillations which limit its performance and decreases its availability. So, in order to improve the performance, IsOWC system using directly modulated laser source is proposed in this work. The system is designed and evaluated to be suitable for high data rate transmissions up to 10 Gbps. The performance of the system is investigated in order to reduce the cost and complexity of link and improving the quality of information signal. Further the proposed IsOWC system is analysed using BER analyser, power meter and oscilloscope Visualizer.

  2. Evaluating satellite-derived long-term historical precipitation datasets for drought monitoring in Chile

    Science.gov (United States)

    Zambrano, Francisco; Wardlow, Brian; Tadesse, Tsegaye; Lillo-Saavedra, Mario; Lagos, Octavio

    2017-04-01

    Precipitation is a key parameter for the study of climate change and variability and the detection and monitoring of natural disaster such as drought. Precipitation datasets that accurately capture the amount and spatial variability of rainfall is critical for drought monitoring and a wide range of other climate applications. This is challenging in many parts of the world, which often have a limited number of weather stations and/or historical data records. Satellite-derived precipitation products offer a viable alternative with several remotely sensed precipitation datasets now available with long historical data records (+30years), which include the Climate Hazards Group InfraRed Precipitation with Station (CHIRPS) and Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Climate Data Record (PERSIANN-CDR) datasets. This study presents a comparative analysis of three historical satellite-based precipitation datasets that include Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) 3B43 version 7 (1998-2015), PERSIANN-CDR (1983-2015) and CHIRPS 2.0 (1981-2015) over Chile to assess their performance across the country and for the case of the two long-term products the applicability for agricultural drought were evaluated when used in the calculation of commonly used drought indicator as the Standardized Precipitation Index (SPI). In this analysis, 278 weather stations of in situ rainfall measurements across Chile were initially compared to the satellite data. The study area (Chile) was divided into five latitudinal zones: North, North-Central, Central, South-Central and South to determine if there were a regional difference among these satellite products, and nine statistics were used to evaluate their performance to estimate the amount and spatial distribution of historical rainfall across Chile. Hierarchical cluster analysis, k-means and singular value decomposition were used to analyze

  3. Integrating Human Performance Metrics into the Future Air Traffic Management Concepts Evaluation Tool Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's Future Air traffic management Concepts Evaluation Tool (FACET) is a simulation tool to evaluate next generation air traffic management (ATM) systems. FACET...

  4. A Satellite-Based Estimation of Evapotranspiration Using Vegetation Index-Temperature Trapezoid Concept: A Case Study in Southern Florida, U.S.A.

    Science.gov (United States)

    Yagci, A. L.; Santanello, J. A., Jr.; Jones, J. W.

    2015-12-01

    One of the key surface variables for hydrological applications, monitoring of natural and anthropogenic water consumption, closing energy balance and water budgets and drought identification is evapotranspiration (ET). There is currently a strong need for high temporal and spatial resolution ET products for climate and hydrological modelers. A satellite-based retrieval method based on vegetation index-temperature trapezoid (VITT) concept has been developed. This model has the ability to generate accurate ET estimates at high temporal and spatial resolutions by taking advantage of key remotely sensed parameters such as vegetation indices (VIs) and land surface temperature (LST) acquired by satellites as well as routinely-measured meteorological variables such as air temperature (Ta) and net radiation. For local-scale applications, the model has been successfully implemented in Python programming language and tested using Landsat satellite products at an eddy covariance flux tower in Florida. It is fully functional and automated such that there is no need of user intervention to run the model. The model development for continental-scale applications using VI and LST products from NASA satellites such as the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Visible Infrared Imaging Radiometer Suite (VIIRS) is currently in progress. The results for local-scale application and early results for continental-scale (US) will be presented and discussed.

  5. Network Performance Evaluation of Abis Interface over DVB-S2 in the GSM over Satellite Network

    Directory of Open Access Journals (Sweden)

    S. B. Musabekov

    2010-01-01

    Full Text Available This paper deals with establishing a GSM link over Satellite. Abis interface, which is defined between Base Transceiver Station (BTS and Base Station Controller (BSC, in a GSM network is considered here to be routed over the Satellite. The satellite link enables a quick and cost-effective GSM link in meagerly populated areas. A different scenario comparison was done to understand the impact of Satellite environment on network availability comparing to terrestrial scenario. We have implemented an Abis interface over DVB S2 in NS2 and evaluated the performance over the high delay and loss satellite channel. Network performance was evaluated with respect to Satellite channel delay and DVB S2 encapsulation efficiency under different amount of user traffic and compared with the terrestrial scenario. The results clearly showed an increased amount of SDCCH and TCH channels required in the case of satellite scenario for the same amount of traffic in comparison to conventional terrestrial scenario. We have optimized the parameters based on the simulation results. Link budget estimation considering DVB-S2 platform was done to find satellite bandwidth and cost requirements for different network setups.

  6. Evaluation of complex heat transfer coefficients for passive heating concepts

    Energy Technology Data Exchange (ETDEWEB)

    Bansal, N.K.; Sodha, M.S.; Singh, S.P.; Ram, S.

    1987-01-01

    Passive heating concepts namely Trombe wall, Water wall and Trans wall have been analysed to obtain overall heat transfer coefficients for average values and for time-dependent variations. The numerical values have been obtained and tabulated for various wall thicknesses.

  7. CFD evaluation of an advanced thrust vector control concept

    Science.gov (United States)

    Tiarn, Weihnurng; Cavalleri, Robert

    1990-01-01

    A potential concept that can offer an alternate method for thrust vector control of the Space Shuttle Solid Rocket Booster is the use of a cylindrical probe that is inserted (on demand) through the wall of the rocket nozzle. This Probe Thrust Vector Control (PTVC) concept is an alternate to that of a gimbaled nozzle or a Liquid Injection Thrust Vector (LITVC) system. The viability of the PTVC concept can be assessed either experimentally and/or with the use of CFD. A purely experimental assessment can be time consuming and expensive, whereas a CFD assessment can be very time- and cost-effective. Two key requirements of the proposed concept are PTVC vectoring performance and the active cooling requirements for the probe to maintain its thermal and structural integrity. An active thermal cooling method is the injection of coolant around the pheriphery of the probe. How much coolant is required and how this coolant distributes itself in the flow field is of major concern. The objective of the work reported here is the use of CFD to answer these question and in the design of test hardware to substantiate the results of the CFD predictions.

  8. Stress revisited : a critical evaluation of the stress concept

    NARCIS (Netherlands)

    Koolhaas, J.M.; Bartolomucci, A; Buwalda, B; Flügge, G; de Boer, Sietse; Korte, S M; Meerlo, P; Murison, R; Olivier, B; Palanza, P; Richter-Levin, G; Sgoifo, A; Steimer, T; Stiedl, O; van Dijk, G; Wöhr, M; Fuchs, E

    2011-01-01

    With the steadily increasing number of publications in the field of stress research it has become evident that the conventional usage of the stress concept bears considerable problems. The use of the term 'stress' to conditions ranging from even the mildest challenging stimulation to severely aversi

  9. Developing and Evaluating Animations for Teaching Quantum Mechanics Concepts

    Science.gov (United States)

    Kohnle, Antje; Douglass, Margaret; Edwards, Tom J.; Gillies, Alastair D.; Hooley, Christopher A.; Sinclair, Bruce D.

    2010-01-01

    In this paper, we describe animations and animated visualizations for introductory and intermediate-level quantum mechanics instruction developed at the University of St Andrews. The animations aim to help students build mental representations of quantum mechanics concepts. They focus on known areas of student difficulty and misconceptions by…

  10. Developing and Evaluating Animations for Teaching Quantum Mechanics Concepts

    Science.gov (United States)

    Kohnle, Antje; Douglass, Margaret; Edwards, Tom J.; Gillies, Alastair D.; Hooley, Christopher A.; Sinclair, Bruce D.

    2010-01-01

    In this paper, we describe animations and animated visualizations for introductory and intermediate-level quantum mechanics instruction developed at the University of St Andrews. The animations aim to help students build mental representations of quantum mechanics concepts. They focus on known areas of student difficulty and misconceptions by…

  11. Aerosol indirect effects – general circulation model intercomparison and evaluation with satellite data

    Directory of Open Access Journals (Sweden)

    M. Schulz

    2009-11-01

    Full Text Available Aerosol indirect effects continue to constitute one of the most important uncertainties for anthropogenic climate perturbations. Within the international AEROCOM initiative, the representation of aerosol-cloud-radiation interactions in ten different general circulation models (GCMs is evaluated using three satellite datasets. The focus is on stratiform liquid water clouds since most GCMs do not include ice nucleation effects, and none of the model explicitly parameterises aerosol effects on convective clouds. We compute statistical relationships between aerosol optical depth (τa and various cloud and radiation quantities in a manner that is consistent between the models and the satellite data. It is found that the model-simulated influence of aerosols on cloud droplet number concentration (Nd compares relatively well to the satellite data at least over the ocean. The relationship between τa and liquid water path is simulated much too strongly by the models. This suggests that the implementation of the second aerosol indirect effect mainly in terms of an autoconversion parameterisation has to be revisited in the GCMs. A positive relationship between total cloud fraction (fcld and τa as found in the satellite data is simulated by the majority of the models, albeit less strongly than that in the satellite data in most of them. In a discussion of the hypotheses proposed in the literature to explain the satellite-derived strong fcld–τa relationship, our results indicate that none can be identified as a unique explanation. Relationships similar to the ones found in satellite data between τa and cloud top temperature or outgoing long-wave radiation (OLR are simulated by only a few GCMs. The GCMs that simulate a negative OLR–τa relationship show a strong positive correlation between

  12. Aerosol indirect effects ? general circulation model intercomparison and evaluation with satellite data

    Energy Technology Data Exchange (ETDEWEB)

    Quaas, Johannes; Ming, Yi; Menon, Surabi; Takemura, Toshihiko; Wang, Minghuai; Penner, Joyce E.; Gettelman, Andrew; Lohmann, Ulrike; Bellouin, Nicolas; Boucher, Olivier; Sayer, Andrew M.; Thomas, Gareth E.; McComiskey, Allison; Feingold, Graham; Hoose, Corinna; Kristansson, Jon Egill; Liu, Xiaohong; Balkanski, Yves; Donner, Leo J.; Ginoux, Paul A.; Stier, Philip; Grandey, Benjamin; Feichter, Johann; Sednev, Igor; Bauer, Susanne E.; Koch, Dorothy; Grainger, Roy G.; Kirkevag, Alf; Iversen, Trond; Seland, Oyvind; Easter, Richard; Ghan, Steven J.; Rasch, Philip J.; Morrison, Hugh; Lamarque, Jean-Francois; Iacono, Michael J.; Kinne, Stefan; Schulz, Michael

    2010-03-12

    Aerosol indirect effects continue to constitute one of the most important uncertainties for anthropogenic climate perturbations. Within the international AEROCOM initiative, the representation of aerosol-cloud-radiation interactions in ten different general circulation models (GCMs) is evaluated using three satellite datasets. The focus is on stratiform liquid water clouds since most GCMs do not include ice nucleation effects, and none of the model explicitly parameterises aerosol effects on convective clouds. We compute statistical relationships between aerosol optical depth ({tau}{sub a}) and various cloud and radiation quantities in a manner that is consistent between the models and the satellite data. It is found that the model-simulated influence of aerosols on cloud droplet number concentration (N{sub d}) compares relatively well to the satellite data at least over the ocean. The relationship between {tau}{sub a} and liquid water path is simulated much too strongly by the models. This suggests that the implementation of the second aerosol indirect effect mainly in terms of an autoconversion parameterisation has to be revisited in the GCMs. A positive relationship between total cloud fraction (f{sub cld}) and {tau}{sub a} as found in the satellite data is simulated by the majority of the models, albeit less strongly than that in the satellite data in most of them. In a discussion of the hypotheses proposed in the literature to explain the satellite-derived strong f{sub cld} - {tau}{sub a} relationship, our results indicate that none can be identified as a unique explanation. Relationships similar to the ones found in satellite data between {tau}{sub a} and cloud top temperature or outgoing long-wave radiation (OLR) are simulated by only a few GCMs. The GCMs that simulate a negative OLR - {tau}{sub a} relationship show a strong positive correlation between {tau}{sub a} and f{sub cld} The short-wave total aerosol radiative forcing as simulated by the GCMs is

  13. An analytic method of space debris cloud evolution and its collision evaluation for constellation satellites

    Science.gov (United States)

    Zhang, Binbin; Wang, Zhaokui; Zhang, Yulin

    2016-09-01

    When a debris cloud is formed in the neighborhood of a constellation, the constellation satellites will face a serious threat of collision. In order to evaluate the collision probability in a long time scale, first we build an analytic model to describe the evolution process of the debris cloud. Under the perturbations of atmospheric drag, nonspherical gravity field, etc., results of numerical simulation indicate that after the breakup of an object, the distribution of debris cloud will evolve into a relatively stable band. Based on the stable distribution characteristic of the debris cloud, fragments are divided into several groups according their orbital heights and area-mass ratios. For each debris group, the dynamics of the distribution process under the perturbation of atmosphere drag is described by a partial differential equation (PDE). Solutions of those PDEs are obtained. And the distribution of the debris cloud can be easily propagated over long time scales. Applying this analytic model, the collision probability between a debris cloud and the Globalstar satellites is analyzed and computed. Results show that the collision probability is nearly 10,000 times of the average collision probability in the near Earth environment. Moreover, as the band distribution of the space debris cloud is stable, the collisional risk on constellation satellites will last for quite a long time.

  14. Evaluation of a physically-based snow model with infrared and microwave satellite-derived estimates

    Science.gov (United States)

    Wang, L.

    2013-05-01

    Snow (with high albedo, as well as low roughness and thermal conductivity) has significant influence on the land-atmosphere interactions in the cold climate and regions of high elevation. The spatial and temporal variability of the snow distribution on a basin scale greatly determines the timing and magnitude of spring snowmelt runoff. For improved water resources management, a physically-based distributed snow model has been developed and applied to the upper Yellow River Basin to provide the outputs of snow variables as well as streamflows from 2001 to 2005. Remotely-sensed infrared information from MODIS satellites has been used to evaluate the model's outputs of spatially-distributed snow cover extent (SCE) and land surface temperature (LST); while the simulated snow depth (SD) and snow water equivalent (SWE) have been compared with the microwave information from SSM/I and AMSR-E satellites. In general, the simulated streamflows (including spring snowmelt) agree fairly well with the gauge-based observations; while the modeled snow variables show acceptable accuracies through comparing to various satellite-derived estimates from infrared or microwave information.;

  15. High altitude aerodynamic platform concept evaluation and prototype engine testing

    Science.gov (United States)

    Akkerman, J. W.

    1984-01-01

    A design concept has been developed for maintaining a 150-pound payload at 60,000 feet altitude for about 50 hours. A 600-pound liftoff weight aerodynamic vehicle is used which operates at sufficient speeds to withstand prevailing winds. It is powered by a turbocharged four-stoke cycle gasoline fueled engine. Endurance time of 100 hours or more appears to be feasible with hydrogen fuel and a lighter payload. A prototype engine has been tested to 40,000 feet simulated altitude. Mismatch of the engine and the turbocharger system flow and problems with fuel/air mixture ratio control characteristics prohibited operation beyond 40,000 feet. But there seems to be no reason why the concept cannot be developed to function as analytically predicted.

  16. Evaluation of Satellite Precipitation Products with Rain Gauge Data at Different Scales: Implications for Hydrological Applications

    Directory of Open Access Journals (Sweden)

    Ruifang Guo

    2016-07-01

    Full Text Available Rain gauge and satellite-retrieved data have been widely used in basin-scale hydrological applications. While rain gauges provide accurate measurements that are generally unevenly distributed in space, satellites offer spatially regular observations and common error prone retrieval. Comparative evaluation of gauge-based and satellite-based data is necessary in hydrological studies, as precipitation is the most important input in basin-scale water balance. This study uses quality-controlled rain gauge data and prevailing satellite products (Tropical Rainfall Measuring Mission (TRMM 3B43, 3B42 and 3B42RT to examine the consistency and discrepancies between them at different scales. Rain gauges and TRMM products were available in the Poyang Lake Basin, China, from 1998 to 2007 (3B42RT: 2000–2007. Our results show that the performance of TRMM products generally increases with increasing spatial scale. At both the monthly and annual scales, the accuracy is highest for TRMM 3B43, with 3B42 second and 3B42RT third. TRMM products generally overestimate precipitation because of a high frequency and degree of overestimation in light and moderate rain cases. At the daily scale, the accuracy is relatively low between TRMM 3B42 and 3B42RT. Meanwhile, the performances of TRMM 3B42 and 3B42RT are highly variable in different seasons. At both the basin and pixel scales, TRMM 3B43 and 3B42 exhibit significant discrepancies from July to September, performing worst in September. For TRMM 3B42RT, all statistical indices fluctuate and are low throughout the year, performing worst in July at the pixel scale and January at the basin scale. Furthermore, the spatial distributions of the statistical indices of TRMM 3B43 and 3B42 performed well, while TRMM 3B42RT displayed a poor performance.

  17. Application of Executable Architectures in Early Concept Evaluation

    Science.gov (United States)

    2015-12-01

    intricate and costly as technology advancements facilitate customer requirements for increased capabilities and extended product lifecycles . Decisions...directly from existing architecture products , with minimal additional system definition or manipulation. Use of EA in early stages of system...throughout the product lifecycle . 11 2.4 Simulation Techniques The modern concept of an executable architecture and application to the DoD was first

  18. Concept and Evaluation of Job Satisfaction: Developed Job Satisfaction Index

    Directory of Open Access Journals (Sweden)

    Hulya Cakmur

    2011-12-01

    Full Text Available SUMMARY: In this study; the reasons and effects determining job satisfaction were analyzed in a theoretical basis by universally defining the content of job satisfaction concept and scales utilized in the assessment of job satisfaction were described. The aim of the study is to introduce the „Developed Job Descriptive Index‟ which has been reestablished according to the needs of our country. [TAF Prev Med Bull 2011; 10(6.000: 759-764

  19. Final Service Provider DevOps concept and evaluation

    OpenAIRE

    Marchetto, Guido; Sisto, Riccardo; John, Wolfgang; Sköldström, Pontus; Pechenot, Bertrand; Németh, Felicián; Pelle, István; Kim, Juhoon; Cai, Xuejun; Fu, Chunyan; Meirosu, Catalin; Pentikousis, Kostas; Sharma, Sachin; Papafili, Ioanna; Spinoso, Serena

    2016-01-01

    This report presents the results of the UNIFY Service Provider DevOps activities. First, we present the final definition and assessment of the concept. SP-DevOps is realized by a combination of various functional components facilitating integrated service verification, efficient and programmable observability, and automated troubleshooting processes. Our assessment shows that SP-DevOps can help providers to reach a medium level of DevOps maturity and allows significant reduction in OPEX. Seco...

  20. Evaluation of a Salutogenetic Concept for Inpatient Psychosomatic Treatment

    Directory of Open Access Journals (Sweden)

    Thilo Hinterberger

    2013-01-01

    Full Text Available The increase of psychosomatic disorders due to cultural changes requires enhanced therapeutic models. This study investigated a salutogenetic treatment concept for inpatient psychosomatic treatment, based on data from more than 11000 patients of a psychosomatic clinic in Germany. The clinic aims at supporting patients’ health improvement by fostering values such as humanity, community, and mindfulness. Most of patients found these values realized in the clinical environment. Self-assessment questionnaires addressing physical and mental health as well as symptom ratings were available for analysis of pre-post-treatment effects and long-term stability using one-year follow-up data, as well as for a comparison with other clinics. With respect to different diagnoses, symptoms improved in self-ratings with average effect sizes between 0.60 and 0.98. About 80% of positive changes could be sustained as determined in a 1-year follow-up survey. Patients with a lower concordance with the values of the clinic showed less health improvement. Compared to 14 other German psychosomatic clinics, the investigated treatment concept resulted in slightly higher decrease in symptoms (e.g., depression scale and a higher self-rated mental and physical improvement in health. The data suggest that a successfully implemented salutogenetic clinical treatment concept not only has positive influence on treatment effects but also provides long-term stability.

  1. Functional analysis in the evaluation of four concepts of planters

    Directory of Open Access Journals (Sweden)

    Reis Ângelo Vieira dos

    2002-01-01

    Full Text Available The essential functions of a planter are to open the planting furrow, meter the seeds, deposit them in the furrow, cover them and compact the soil around them. The planter precision is affected, in some way, by each of those functions. Function analysis is a tool used in the conceptual phase of product design which allows an abstract formulation for the function of the technical system, thus making it very useful in product design and in the analysis of existing products. Therefore, the technique of function analysis makes it possible to identify, in the various concepts of planters sold in the Brazilian market, which function is not well implemented when considering precision planting of small grains, being this the main objective of this study. This study has made it possible to conclude, among other things, that in all concepts of planters analyzed, the sub-functions of metering seeds and that of depositing seeds in the soil were not satisfactorily implemented for the precision planting of small grains. This points out the need of searching for other concepts of planters or the adoption of different solution principles for these functions.

  2. Evaluation of Vortex Chamber Concepts for Liquid Rocket Engine Applications

    Science.gov (United States)

    Trinh, Huu Phuoc; Knuth, Williams; Michaels, Scott; Turner, James E. (Technical Monitor)

    2000-01-01

    Rocket-based combined-cycle engines (RBBC) being considered at NASA for future generation launch vehicles feature clusters of small rocket thrusters as part of the engine components. Depending on specific RBBC concepts, these thrusters may be operated at various operating conditions including power level and/or propellant mixture ratio variations. To pursue technology developments for future launch vehicles, NASA/Marshall Space Flight Center (MSFC) is examining vortex chamber concepts for the subject cycle engine application. Past studies indicated that the vortex chamber schemes potentially have a number of advantages over conventional chamber methods. Due to the nature of the vortex flow, relatively cooler propellant streams tend to flow along the chamber wall. Hence, the thruster chamber can be operated without the need of any cooling techniques. This vortex flow also creates strong turbulence, which promotes the propellant mixing process. Consequently, the subject chamber concepts not only offer the system simplicity but they also would enhance the combustion performance. The test results showed that the chamber performance was markedly high even at a low chamber length-to- diameter ratio (L/D). This incentive can be translated to a convenience in the thrust chamber packaging.

  3. Derivation and evaluation of land surface temperature from the geostationary operational environmental satellite series

    Science.gov (United States)

    Fang, Li

    The Geostationary Operational Environmental Satellites (GOES) have been continuously monitoring the earth surface since 1970, providing valuable and intensive data from a very broad range of wavelengths, day and night. The National Oceanic and Atmospheric Administration's (NOAA's) National Environmental Satellite, Data, and Information Service (NESDIS) is currently operating GOES-15 and GOES-13. The design of the GOES series is now heading to the 4 th generation. GOES-R, as a representative of the new generation of the GOES series, is scheduled to be launched in 2015 with higher spatial and temporal resolution images and full-time soundings. These frequent observations provided by GOES Image make them attractive for deriving information on the diurnal land surface temperature (LST) cycle and diurnal temperature range (DTR). These parameters are of great value for research on the Earth's diurnal variability and climate change. Accurate derivation of satellite-based LSTs from thermal infrared data has long been an interesting and challenging research area. To better support the research on climate change, the generation of consistent GOES LST products for both GOES-East and GOES-West from operational dataset as well as historical archive is in great demand. The derivation of GOES LST products and the evaluation of proposed retrieval methods are two major objectives of this study. Literature relevant to satellite-based LST retrieval techniques was reviewed. Specifically, the evolution of two LST algorithm families and LST retrieval methods for geostationary satellites were summarized in this dissertation. Literature relevant to the evaluation of satellite-based LSTs was also reviewed. All the existing methods are a valuable reference to develop the GOES LST product. The primary objective of this dissertation is the development of models for deriving consistent GOES LSTs with high spatial and high temporal coverage. Proper LST retrieval algorithms were studied

  4. Testing the Participatory Education Evaluation Concept in a National Context

    Science.gov (United States)

    Pietilainen, Ville

    2012-01-01

    The article focuses on the realisation of participatory evaluation (PE) in national educational evaluation activity. The realisation of PE is examined by adapting the Daigneault and Jacob model (2009; originally Cousins & Whitmore, 1998) to five national-level educational evaluations carried out in Finland. According to the chosen frame of…

  5. Evaluation of short-period rainfall estimates from Kalpana-1 satellite using MET software

    Indian Academy of Sciences (India)

    Soma Sen Roy; Subhendu Brata Saha; Hashmi Fatima; S K Roy Bhowmik; P K Kundu

    2012-10-01

    The INSAT Multispectral Rainfall Algorithm (IMSRA) technique for rainfall estimation, has recently been developed to meet the shortcomings of the Global Precipitation Index (GPI) technique of rainfall estimation from the data of geostationary satellites; especially for accurate short period rainfall estimates. This study evaluates the 3-hourly precipitation estimates by this technique as well as the rainfall estimates by the GPI technique using data of the Kalpana-1 satellite, over the Indian region for the south-west monsoon season of 2010 to understand their relative strengths and weaknesses in estimating short period rainfall. The gridded 3 hourly accumulated TRMM satellite (3B42 V6 product or TMPA product) and surface raingauge data for stations over the Indian region for the same period is used as the standard measure of rainfall estimates. The Method for Object-based Diagnostic Evaluation (MODE) utility of the METv3.0 software, has been used for the evaluation purpose. The results show that the new IMSRA technique is closer to the TMPA rainfall estimate, in terms of areal spread, geometric shape and location of rainfall areas, as compared to the GPI technique. The overlap of matching rainfall areas with respect to TMPA rainfall patches is also higher for the IMSRA estimates as compared to the GPI values. However, both satellite rainfall estimates are observed to be generally higher compared to the TMPA measurements. However, the values for the highest 10% of the rainfall rates in any rainfall patch, is generally higher for rainfall measured by the IMSRA technique, as compared to the estimates by the GPI technique. This may partly be due to the capping maximum limit of 3 mm/hr for rainfall measured by the GPI technique limits the total 3-hour accumulation to 9 mm even during heavy rainfall episodes. This is not so with IMSRA technique, which has no such limiting value. However, this general overestimation of the rainfall amount, measured by both techniques

  6. Evaluation of SCaMPR Satellite QPEs for Operational Hydrologic Prediction

    Science.gov (United States)

    LEE, H.; Zhang, Y.; Seo, D.; Kitzmiller, D. H.; Kuligowski, R. J.; Corby, R.

    2011-12-01

    National Weather Service (NWS) River Forecast Centers (RFCs) use rain gauge or radar-gauge multi-sensor quantitative precipitation estimates (QPEs) as the primary rainfall input to their operational hydrologic models. In areas with poor radar and rain gauge coverage, satellite-based QPEs are a potential alternative. In this work, we evaluated the utility of satellite-based QPEs produced via the Self-Calibrating Multivariate Precipitation Retrieval (SCaMPR) algorithm for operational hydrologic modeling for a set of basins in Texas and Louisiana for the period of 2000-7. First, we assessed the relative accuracy of two sets of SCaMPR QPEs versus gauge-only QPE, with operational multi-sensor QPEs as the reference. One set used only operational polar orbiting satellite microwave input as the predictors, the other included Tropical Rainfall Measuring Mission (TRMM) rain rates in the calibration process. We then performed hydrologic simulations using these QPEs and evaluated the simulations. Results indicated that a) SCaMPR QPEs showed better/worse skill than the gauge-only QPEs in resolving heavy precipitation at 1-h/24-h time intervals in terms of Critical Success Index (CSI); b) SCaMPR QPEs underperformed gauge-only QPEs in simulating flood events; and c) ingesting TRMM rainfall rates helped enhance the hydrologic utility of SCaMPR QPE, by mitigating the positive bias of SCaMPR QPEs, elevating the detection rates of heavy rainfall, and improving the simulation of flood discharge. Our findings suggest that the superior performance of gauge-only QPEs versus SCaMPR in hydrologic simulations is tied to its better accuracy at 24-h scale. The implication of the scale dependence in the relative performance of SCaMPR QPEs to their potential hydrologic utility is discussed.

  7. Aeroacoustic Evaluation of Flap and Landing Gear Noise Reduction Concepts

    Science.gov (United States)

    Khorrami, Mehdi R.; Humphreys, William M., Jr.; Lockard, David P.; Ravetta, Patricio A.

    2014-01-01

    Aeroacoustic measurements for a semi-span, 18% scale, high-fidelity Gulfstream aircraft model are presented. The model was used as a test bed to conduct detailed studies of flap and main landing gear noise sources and to determine the effectiveness of numerous noise mitigation concepts. Using a traversing microphone array in the flyover direction, an extensive set of acoustic data was obtained in the NASA Langley Research Center 14- by 22-Foot Subsonic Tunnel with the facility in the acoustically treated open-wall (jet) mode. Most of the information was acquired with the model in a landing configuration with the flap deflected 39 deg and the main landing gear alternately installed and removed. Data were obtained at Mach numbers of 0.16, 0.20, and 0.24 over directivity angles between 56 deg and 116 deg, with 90 deg representing the overhead direction. Measured acoustic spectra showed that several of the tested flap noise reduction concepts decrease the sound pressure levels by 2 - 4 dB over the entire frequency range at all directivity angles. Slightly lower levels of noise reduction from the main landing gear were obtained through the simultaneous application of various gear devices. Measured aerodynamic forces indicated that the tested gear/flap noise abatement technologies have a negligible impact on the aerodynamic performance of the aircraft model.

  8. Evaluating Cloud and Precipitation Processes in Numerical Models using Current and Potential Future Satellite Missions

    Science.gov (United States)

    van den Heever, S. C.; Tao, W. K.; Skofronick Jackson, G.; Tanelli, S.; L'Ecuyer, T. S.; Petersen, W. A.; Kummerow, C. D.

    2015-12-01

    Cloud, aerosol and precipitation processes play a fundamental role in the water and energy cycle. It is critical to accurately represent these microphysical processes in numerical models if we are to better predict cloud and precipitation properties on weather through climate timescales. Much has been learned about cloud properties and precipitation characteristics from NASA satellite missions such as TRMM, CloudSat, and more recently GPM. Furthermore, data from these missions have been successfully utilized in evaluating the microphysical schemes in cloud-resolving models (CRMs) and global models. However, there are still many uncertainties associated with these microphysics schemes. These uncertainties can be attributed, at least in part, to the fact that microphysical processes cannot be directly observed or measured, but instead have to be inferred from those cloud properties that can be measured. Evaluation of microphysical parameterizations are becoming increasingly important as enhanced computational capabilities are facilitating the use of more sophisticated schemes in CRMs, and as future global models are being run on what has traditionally been regarded as cloud-resolving scales using CRM microphysical schemes. In this talk we will demonstrate how TRMM, CloudSat and GPM data have been used to evaluate different aspects of current CRM microphysical schemes, providing examples of where these approaches have been successful. We will also highlight CRM microphysical processes that have not been well evaluated and suggest approaches for addressing such issues. Finally, we will introduce a potential NASA satellite mission, the Cloud and Precipitation Processes Mission (CAPPM), which would facilitate the development and evaluation of different microphysical-dynamical feedbacks in numerical models.

  9. Evaluating Satellite Products for Precipitation Estimation in Mountain Regions: A Case Study for Nepal

    Directory of Open Access Journals (Sweden)

    Tarendra Lakhankar

    2013-08-01

    Full Text Available Precipitation in mountain regions is often highly variable and poorly observed, limiting abilities to manage water resource challenges. Here, we evaluate remote sensing and ground station-based gridded precipitation products over Nepal against weather station precipitation observations on a monthly timescale. We find that the Tropical Rainfall Measuring Mission (TRMM 3B-43 precipitation product exhibits little mean bias and reasonable skill in giving precipitation over Nepal. Compared to station observations, the TRMM precipitation product showed an overall Nash-Sutcliffe efficiency of 0.49, which is similar to the skill of the gridded station-based product Asian Precipitation-Highly Resolved Observational Data Integration Towards Evaluation of Water Resources (APHRODITE. The other satellite precipitation products considered (Global Satellite Mapping of Precipitation (GSMaP, the Climate Prediction Center Morphing technique (CMORPH, Precipitation Estimation from Remotely Sensed Information Using Artificial Neural Networks-Cloud Classification System (PERSIANN-CCS were less skillful, as judged by Nash-Sutcliffe efficiency, and, on average, substantially underestimated precipitation compared to station observations, despite their, in some cases, higher nominal spatial resolution compared to TRMM. None of the products fully captured the dependence of mean precipitation on elevation seen in the station observations. Overall, the TRMM product is promising for use in water resources applications.

  10. Oil-points - Designers means to evaluate sustainability of concepts

    DEFF Research Database (Denmark)

    Bey, Niki; Lenau, Torben Anker

    1998-01-01

    Designers have an essential influence on product design and are therefore one target group for environmental evaluation methods. This implies, that such evaluation methods have to meet designers requirements. Evaluation of sustainability of products is often done using formal Life Cycle Assessment....... This is investigated by means of three case studies where environmental impact is estimated using the EDIP method, the Eco-indicator 95 method, and the Oil Point method proposed by the authors. It is found that the results obtained using Oil Points are in acceptable conformity with the results obtained with more...

  11. Oil-points - Designers means to evaluate sustainability of concepts

    DEFF Research Database (Denmark)

    Bey, Niki; Lenau, Torben Anker

    1998-01-01

    Designers have an essential influence on product design and are therefore one target group for environmental evaluation methods. This implies, that such evaluation methods have to meet designers requirements. Evaluation of sustainability of products is often done using formal Life Cycle Assessment....... This is investigated by means of three case studies where environmental impact is estimated using the EDIP method, the Eco-indicator 95 method, and the Oil Point method proposed by the authors. It is found that the results obtained using Oil Points are in acceptable conformity with the results obtained with more...

  12. Developmental evaluation applying complexity concepts to enhance innovation and use

    CERN Document Server

    Patton, Michael Quinn

    2011-01-01

    Developmental evaluation (DE) offers a powerful approach to monitoring and supporting social innovations by working in partnership with program decision makers. In this book, eminent authority Michael Quinn Patton shows how to conduct evaluations within a DE framework. Patton draws on insights about complex dynamic systems, uncertainty, nonlinearity, and emergence. He illustrates how DE can be used for a range of purposes: ongoing program development, adapting effective principles of practice to local contexts, generating innovations and taking them to scale, and facilitating rapid response in crisis situations. Students and practicing evaluators will appreciate the book's extensive case examples and stories, cartoons, clear writing style, "closer look" sidebars, and summary tables. Provided is essential guidance for making evaluations useful, practical, and credible in support of social change.

  13. Conceptions and Practices in Teaching and Learning: Implications for the Evaluation of Teaching Quality

    Science.gov (United States)

    Zerihun, Zenawi; Beishuizen, Jos; Van Os, Willem

    2011-01-01

    This study was conducted in two public universities in Ethiopia to assess the impact of conceptions of teaching and learning on the evaluation of teaching quality. Students' and teachers' approaches to teaching and learning and their conceptions of the meaning of teaching have been examined. Results indicated that both teachers and students…

  14. Evaluation of Eleventh Grade Turkish Pupils' Comprehension of General Chemistry Concepts

    Science.gov (United States)

    Belge Can, Hatice; Boz, Yezdan

    2011-01-01

    The main purpose of this study is to evaluate eleventh grade Turkish pupils' comprehension of various general chemistry concepts which in turn enables to investigate chemistry concepts which are easier and harder for students to comprehend. Examining the effect of gender and last semester chemistry course grades on pupils' comprehension of general…

  15. Evaluation of ADAM/1 model for advanced coal extraction concepts

    Science.gov (United States)

    Deshpande, G. K.; Gangal, M. D.

    1982-01-01

    Several existing computer programs for estimating life cycle cost of mining systems were evaluated. A commercially available program, ADAM/1 was found to be satisfactory in relation to the needs of the advanced coal extraction project. Two test cases were run to confirm the ability of the program to handle nonconventional mining equipment and procedures. The results were satisfactory. The model, therefore, is recommended to the project team for evaluation of their conceptual designs.

  16. Evaluation of Health in All Policies: concept, theory and application.

    Science.gov (United States)

    Baum, Fran; Lawless, Angela; Delany, Toni; Macdougall, Colin; Williams, Carmel; Broderick, Danny; Wildgoose, Deborah; Harris, Elizabeth; Mcdermott, Dennis; Kickbusch, Ilona; Popay, Jennie; Marmot, Michael

    2014-06-01

    This article describes some of the crucial theoretical, methodological and practical issues that need to be considered when evaluating Health in All Policies (HiAP) initiatives. The approaches that have been applied to evaluate HiAP in South Australia are drawn upon as case studies, and early findings from this evaluative research are provided. The South Australian evaluation of HiAP is based on a close partnership between researchers and public servants. The article describes the South Australian HiAP research partnership and considers its benefits and drawbacks in terms of the impact on the scope of the research, the types of evidence that can be collected and the implications for knowledge transfer. This partnership evolved from the conduct of process evaluations and is continuing to develop through joint collaboration on an Australian National Health & Medical Research Council grant. The South Australian research is not seeking to establish causality through statistical tests of correlations, but instead by creating a 'burden of evidence' which supports logically coherent chains of relations. These chains emerge through contrasting and comparing findings from many relevant and extant forms of evidence. As such, program logic is being used to attribute policy change to eventual health outcomes. The article presents the preliminary program logic model and describes the early work of applying the program logic approach to HiAP. The article concludes with an assessment of factors that have accounted for HiAP being sustained in South Australia from 2008 to 2013.

  17. A review about the use of concept maps as learning and evaluation strategy

    Directory of Open Access Journals (Sweden)

    Adriana Marques Toigo

    2012-06-01

    Full Text Available In this paper we present a review of national and international journals and from annals of the I, II and III International Conference on Concept Mapping, until 2010, on the use of concept mapping in formal education. It is discussed, at the light of the Meaningful Learning Theory and the Conceptual Fields Theory, papers concerning concept maps specifically as didactical and evaluation strategy, cause these were the perspectives used in the cited study. The theoretical frameworks and results from the researched papers are pointed and compared. In the final remarks we present a synthesis with suggestions on the use of the concept maps, also taking account of the authors’ experiences.

  18. The Delta low-inclination satellite concept, an opportunity to enhance the science return of the Swarm mission

    DEFF Research Database (Denmark)

    Hulot, Gauthier; Leger, Jean-Michel; Olsen, Nils;

    of these data, however, would be possible if a fourth “Delta” satellite were to be launched soon enough to join the constellation at a similar altitude but much lower inclination orbit (such as 60°). Such a satellite would provide less geographical coverage but a much faster mapping of all local times over...... and investigation efforts are now hampered by the still limited local time coverage provided by this constellation. This affects our ability to accurately characterize time changes in the ionospheric and magnetospheric field contributions, and to model the electrical conductivity of the Earth’s mantle. It also...... these latitudes. In this presentation we will present the rational for such a Delta mission and discuss the benefit it would bring....

  19. Evaluation of Daily Evapotranspiration Over Orchards Using METRIC Approach and Landsat Satellite Observations

    Science.gov (United States)

    He, R.; Jin, Y.; Daniele, Z.; Kandelous, M. M.; Kent, E. R.

    2016-12-01

    The pistachio and almond acreage in California has been rapidly growing in the past 10 years, raising concerns about competition for limited water resources in California. A robust and cost-effective mapping of crop water use, mostly evapotranspiration (ET), by orchards, is needed for improved farm-level irrigation management and regional water planning. METRIC™, a satellite-based surface energy balance approach, has been widely used to map field-scale crop ET, mostly over row crops. We here aim to apply METRIC with Landsat satellite observations over California's orchards and evaluate the ET estimates by comparing with field measurements in South San Joaquin Valley, California. Reference ET of grass (ETo) from California Irrigation Management Information system (CIMIS) stations was used to estimate daily ET of commercial almond and pistachio orchards. Our comparisons showed that METRIC-Landsat ET daily estimates agreed well with ET measured by the eddy covariance and surface renewal stations, with a RMSE of 1.25 and a correlation coefficient of 0.84 for the pistachio orchard. A slight high bias of satellite based ET estimates was found for both pistachio and almond orchards. We also found time series of NDVI was highly correlated with ET temporal dynamics within each field, but the correlation was reduced to 0.56 when all fields were pooled together. Net radiation, however, remained highly correlated with ET across all the fields. The METRIC ET was able to distinguish the differences in ET among salt- and non-salt affected pistachio orchards, e.g., mean daily ET during growing season in salt-affected orchards was lower than that of non-salt affected one by 0.87 mm/day. The remote sensing based ET estimate will support a variety of state and local interests in water use and management, for both planning and regulatory/compliance purposes, and provide the farmers observation-based guidance for site-specific and time-sensitive irrigation management.

  20. Evaluation of satellite rainfall estimates for drought and flood monitoring in Mozambique

    Science.gov (United States)

    Tote, Carolien; Patricio, Domingos; Boogaard, Hendrik; van der Wijngaart, Raymond; Tarnavsky, Elena; Funk, Christopher C.

    2015-01-01

    Satellite derived rainfall products are useful for drought and flood early warning and overcome the problem of sparse, unevenly distributed and erratic rain gauge observations, provided their accuracy is well known. Mozambique is highly vulnerable to extreme weather events such as major droughts and floods and thus, an understanding of the strengths and weaknesses of different rainfall products is valuable. Three dekadal (10-day) gridded satellite rainfall products (TAMSAT African Rainfall Climatology And Time-series (TARCAT) v2.0, Famine Early Warning System NETwork (FEWS NET) Rainfall Estimate (RFE) v2.0, and Climate Hazards Group InfraRed Precipitation with Stations (CHIRPS)) are compared to independent gauge data (2001–2012). This is done using pairwise comparison statistics to evaluate the performance in estimating rainfall amounts and categorical statistics to assess rain-detection capabilities. The analysis was performed for different rainfall categories, over the seasonal cycle and for regions dominated by different weather systems. Overall, satellite products overestimate low and underestimate high dekadal rainfall values. The RFE and CHIRPS products perform as good, generally outperforming TARCAT on the majority of statistical measures of skill. TARCAT detects best the relative frequency of rainfall events, while RFE underestimates and CHIRPS overestimates the rainfall events frequency. Differences in products performance disappear with higher rainfall and all products achieve better results during the wet season. During the cyclone season, CHIRPS shows the best results, while RFE outperforms the other products for lower dekadal rainfall. Products blending thermal infrared and passive microwave imagery perform better than infrared only products and particularly when meteorological patterns are more complex, such as over the coastal, central and south regions of Mozambique, where precipitation is influenced by frontal systems.

  1. Evaluation of Satellite Rainfall Estimates for Drought and Flood Monitoring in Mozambique

    Directory of Open Access Journals (Sweden)

    Carolien Toté

    2015-02-01

    Full Text Available Satellite derived rainfall products are useful for drought and flood early warning and overcome the problem of sparse, unevenly distributed and erratic rain gauge observations, provided their accuracy is well known. Mozambique is highly vulnerable to extreme weather events such as major droughts and floods and thus, an understanding of the strengths and weaknesses of different rainfall products is valuable. Three dekadal (10-day gridded satellite rainfall products (TAMSAT African Rainfall Climatology And Time-series (TARCAT v2.0, Famine Early Warning System NETwork (FEWS NET Rainfall Estimate (RFE v2.0, and Climate Hazards Group InfraRed Precipitation with Stations (CHIRPS are compared to independent gauge data (2001–2012. This is done using pairwise comparison statistics to evaluate the performance in estimating rainfall amounts and categorical statistics to assess rain-detection capabilities. The analysis was performed for different rainfall categories, over the seasonal cycle and for regions dominated by different weather systems. Overall, satellite products overestimate low and underestimate high dekadal rainfall values. The RFE and CHIRPS products perform as good, generally outperforming TARCAT on the majority of statistical measures of skill. TARCAT detects best the relative frequency of rainfall events, while RFE underestimates and CHIRPS overestimates the rainfall events frequency. Differences in products performance disappear with higher rainfall and all products achieve better results during the wet season. During the cyclone season, CHIRPS shows the best results, while RFE outperforms the other products for lower dekadal rainfall. Products blending thermal infrared and passive microwave imagery perform better than infrared only products and particularly when meteorological patterns are more complex, such as over the coastal, central and south regions of Mozambique, where precipitation is influenced by frontal systems.

  2. Evaluation of algorithms for fire detection and mapping across North America from satellite

    Science.gov (United States)

    Li, Zhanqing; Fraser, R.; Jin, J.; Abuelgasim, A. A.; Csiszar, I.; Gong, P.; Pu, R.; Hao, W.

    2003-01-01

    This paper presents an evaluation of advanced very high resolution radiometer (AVHRR)-based remote sensing algorithms for detecting active vegetation fires [, 2000a] and mapping burned areas [, 2000] throughout North America. The procedures were originally designed for application in Canada with AVHRR data aboard the NOAA 14 satellite. They were tested here with both NOAA 11 and NOAA 14 covering the period 1989-2000. It was found that the active fire detection algorithm performs well with low commission and omission error rates over forested regions in the absence of cloud cover. Moderate errors were found over semi-arid areas covered by thin clouds, as well as along rivers and around lakes observed from sun-glint angles. A modification to a fire algorithm threshold and the addition of a new test can significantly improve the detection accuracy. Burned areas mapped by satellite were compared against extensive fire polygon data acquired by U.S. forest agencies in five western states. The satellite-based mapping matches nearly 90% of total forested burned area, with the difference being mainly attributable to omission of some nonburned islands and patches within the fire polygons. In addition, it maps a significant area of burning outside the fire polygons that appear to be true fires. The 10% omission error was found to be caused mainly by three factors: lack or insufficient number of active fires, partial burning, and vegetation recovery after early season burning. In addition to total area, the location and shapes of burned scars are consistent with the ground-based maps. Overall, the two algorithms are competent for detecting and mapping forest fires in North America north of Mexico with minor modifications.

  3. Evaluation of Satellite Image Correction Methods Caused by Differential Terrain Illumination

    Directory of Open Access Journals (Sweden)

    Purnama Budi Santosa

    2016-08-01

    Full Text Available The problem due to differential terrain illumination on satellite imagery is experienced by most of areas which are on mountainous terrain. This may cause variations in reflectance of similar ground features which lead to a misclassification of land cover classes due to different topographic positions. This phenomenon most commonly occurred in the areas which are located on southern and northern hemisphere because of the low sun inclination. This problem has been a major interest for researchers to be solved prior to the land cover classification process. For satellite images which experience this kind of problem, topographic correction need to be applied in order to reduce the illumination effects prior to land cover classification process. This research is aimed at conducting topographic correction of multi spectral SPOT satellite data as well as evaluating the three topographic correction methods. They are Cosine which is based on Lambertian reflectance assumption, as well as Minnaert correction and C correction methods which are based on non-Lambertian reflectance assumption. The data used in this study are two scenes of SPOT images of forested mountainous area of Miyazaki Prefecture, Kyushu, Japan. Research steps had been conducted in this study including geometric correction, sample data collection for calculating Minnaert constants and C constants at location which represents the whole study area, topographic correction for two scenes SPOT images, and results analysis. The results show that Cosine method did not show good performance for the study area which is topographically dominated by rugged terrain. Whereas Minnaert method and C method gave satisfactory results as is indicated by the statistical data as well as visual interpretation. However the Minnaert correction method showed slightly better performance than the C correction method.

  4. Bibliography for the Satellite Power System (SPS) Concept Development and Evaluation Program

    Energy Technology Data Exchange (ETDEWEB)

    Abromavage, M.; Calzadilla, R.; Murray, M.

    1981-04-01

    This bibliography encompasses systems definition and engineering aspects; environmental assessment of microwave health and ecology, risks to space workers and atmospheric effects; a societal assessment covering resource requirements (land and materials) international and institutional issues; and a comparative assessment of the SPS Reference System relative to other advanced energy technologies, such as fusion. (MHR)

  5. Sustainable urban built environment: Modern management concepts and evaluation methods

    Science.gov (United States)

    Ovsiannikova, Tatiana; Nikolaenko, Mariya

    2017-01-01

    The paper is focused on the analysis of modern concepts in urban development management. It is established that they are based on the principles of ecocentrism and anthropocentrism. The purpose of this research is to develop a system of quality indicators of urban built environment and justification of their application in management of city development. The need for observing the indicators characterizing the urban built environment in the planning of the territory development was proved. Based on the data and reports of the Russian and international organizations the analysis of the existing systems of urban development indicators is made. The suggested solution is to extend the existing indicators systems with that related to urban built environment quality which are recommended for planning urban areas development. The proposed system of indicators includes private, aggregate, normalized, and integrated urban built environment quality indicators using methods of economic-statistical and comparative analysis and index method. Application of these methods allowed calculating the indicators for urban areas of Tomsk Region. The results of calculations are presented in the paper. According to normalized indicators the priority areas for investment and development of urban areas were determined. The scenario conditions allowed estimating changes of quality indicators for urban built environment. Finally, the paper suggests recommendations for making management decisions when creating sustainable environment of life in urban areas.

  6. Evaluation of pressure sensing concepts: A technology assessment

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, R.L.; Thacker, L.H.

    1993-09-01

    Advanced distributed control systems for electric power plants will require more accurate and reliable pressure gauges than those now installed. Future developments in power plant control systems are expected to use digital/optical networks rather than the analog/electric data transmission used in existing plants. Many pressure transmitters now installed use oil filling to separate process fluids from the gauge mechanism and are subject to insidious failures when the oil leaks. Testing and maintenance of pressure channels occupy a disproportionately large amount of effort to restore their accuracy and verify their operability. These and similar concerns have prompted an assessment of a broad spectrum of sensor technologies to aid in selecting the most likely candidates for adaptation to power plant applications. Ten representative conventional and thirty innovational pressure sensors are described and compared. Particular emphasis is focused on two categories: Silicon-integrated pressure sensors and fiber-optic sensors, and both of these categories are discussed in detail. Additional attractive concepts include variable reluctance gauges and resonant structure gauges that may not require oil buffering from the process fluid.

  7. Systematic Evaluation of Satellite-Based Rainfall Products over the Brahmaputra Basin for Hydrological Applications

    Directory of Open Access Journals (Sweden)

    Sagar Ratna Bajracharya

    2015-01-01

    Full Text Available Estimation of the flow generated in the Brahmaputra river basin is important for establishing an effective flood prediction and warning services as well as for water resources assessment and management. But this is a data scarce region with few and unevenly distributed hydrometeorological stations. Five high-resolution satellite rainfall products (CPC RFE2.0, RFE2.0-Modified, CMORPH, GSMaP, and TRMM 3B42 were evaluated at different spatial and temporal resolutions (daily, dekadal, monthly, and seasonal with observed rain gauge data from 2004 to 2006 to determine their ability to fill the data gap and suitability for use in hydrological and water resources management applications. Grid-to-grid (G-G and catchment-to-catchment (C-C comparisons were performed using the verification methods developed by the International Precipitation Working Group (IPWG. Comparing different products, RFE2.0-Modified, TRMM 3B42, and CMORPH performed best; they all detected heavy, moderate, and low rainfall but still significantly underestimated magnitude of rainfall, particularly in orographically influenced areas. Overall, RFE2.0-Modified performed best showing a high correlation coefficient with observed data and low mean absolute error, root mean square error, and multiple bias and is reasonably good at detecting the occurrence of rainfall. TRMM 3B42 showed the second best performance. The study demonstrates that there is a potential use of satellite rainfall in a data scarce region.

  8. Evaluating the Application of Multi-Satellite Observations in Hydrologic Modeling

    Science.gov (United States)

    Bolten, John

    2011-01-01

    When monitoring local or regional hydrosphere dynamics for applications such as agricultural productivity or drought and flooding events, it is necessary to have accurate, high-resolution estimates of terrestrial water and energy storages. Though in-situ observations provide reliable estimates of hydrologic states and fluxes, they are only capable of accurately capturing the dynamics at relatively discrete points in space and time, which makes them inadequate for characterizing the variability of the water budget across scales. In contrast, satellite-based remote sensing is ideal for providing observations of hydrological states and fluxes because it provides spatially-distributed observations at spatial and temporal scales required for regional land surface process modeling. Due to the continued progress in algorithm development and emerging satellite technology, we now have near-real time monitoring of several components of the water cycle including precipitation, soil moisture, lake and river height, terrestrial water storage, snow cover, and evapotranspiration. As these data become more readily available, their application to hydrologic modeling is becoming more common, however there remains little consensus on the most appropriate method for optimal integration and evaluation in regard to hydrological applications. Here we present two case studies operationally applying several remotely sensed products from AMSR-E, GRACE, and MODIS and discuss assimilation strategies, ease of integration and interpretation, and methods for quantifying the success of the application methodology.

  9. Use of satellite telemetry to evaluate movements of caribou within subsistence hunting areas in northern Alaska

    Directory of Open Access Journals (Sweden)

    Alexander K. Prichard

    2003-04-01

    Full Text Available Caribou from the Teshekpuk Herd (TH are an important subsistence resource for residents of Inupiaq villages in northern Alaska. In recent years the use of satellite telemetry has increased the understanding of the herd's annual movements and interactions with other herds. Most caribou of the TH are within the National Petroleum Reserve—Alaska (NPRA throughout the year. The northeastern portion of NPRA has undergone two lease sales for oil and gas exploration, and lease sales are tentatively scheduled for the central/northwest portion of the NPRA in 2004. During 1990—1999, the movements of 27 caribou from the TH were tracked using satellite collars. We evaluated the proportion of time caribou were available to Inupiaq hunters by incorporating maps depicting subsistence-use areas for each of seven Inupiaq villages, and then examining seasonal and annual movements of caribou relative to those areas. By combining caribou locations with subsistence hunting areas, we were able to explore spatial and temporal patterns in caribou availability to subsistence hunters. This information is useful for managers to set appropriate hunting regulations and for devising sensible alternatives and mitigation of likely petroleum development in NPRA.

  10. Potential and limitations of multidecadal satellite soil moisture observations for selected climate model evaluation studies

    Directory of Open Access Journals (Sweden)

    A. Loew

    2013-09-01

    Full Text Available Soil moisture is an essential climate variable (ECV of major importance for land–atmosphere interactions and global hydrology. An appropriate representation of soil moisture dynamics in global climate models is therefore important. Recently, a first multidecadal, observation-based soil moisture dataset has become available that provides information on soil moisture dynamics from satellite observations (ECVSM, essential climate variable soil moisture. The present study investigates the potential and limitations of this new dataset for several applications in climate model evaluation. We compare soil moisture data from satellite observations, reanalysis and simulations from a state-of-the-art land surface model and analyze relationships between soil moisture and precipitation anomalies in the different dataset. Other potential applications like model parameter optimization or model initialization are not investigated in the present study. In a detailed regional study, we show that ECVSM is capable to capture well the interannual and intraannual soil moisture and precipitation dynamics in the Sahelian region. Current deficits of the new dataset are critically discussed and summarized at the end of the paper to provide guidance for an appropriate usage of the ECVSM dataset for climate studies.

  11. Evaluation of CONAP Concept for Advanced ABM Nosetips

    Science.gov (United States)

    1976-11-01

    TIPO [ MODEL PESIRE PROPERTIES I Ii I I III III I I I to 100 1000 I1100 100.000 INE TIAL AI$ IA4CI CO FFICItNT P X 10 F? I Figure 2-29. Porous...34Rain/Ice Erosion Resistant Nosetip/iPet Shield Evaluation and Development, Vol. II Erosion Resistant GASJET Nosetip" DNA 3562F-2, 1 March 1975 9

  12. Evaluation of Preservice Elementary Teachers’ Concept Images for Quadrilaterals

    OpenAIRE

    ERŞEN, Zeynep; KARAKUŞ, Fatih

    2013-01-01

    The aim of this study was to determine preservice elementary teachers' images for some special quadrilaterals. The case study was conducted with 6 preservice elementary teachers. The data were collected by clinical interviews to evaluate preservice teachers’ images for quadrilaterals. Hence, initially, the questionnaire consisting of two parts was given to preservice teachers. In the first part, preservice teachers were asked to draw 3 different squares, rectangles, trapezoids and parall...

  13. Cloud retrievals from satellite data using optimal estimation: evaluation and application to ATSR

    Directory of Open Access Journals (Sweden)

    C. A. Poulsen

    2012-08-01

    Full Text Available Clouds play an important role in balancing the Earth's radiation budget. Hence, it is vital that cloud climatologies are produced that quantify cloud macro and micro physical parameters and the associated uncertainty. In this paper, we present an algorithm ORAC (Oxford-RAL retrieval of Aerosol and Cloud which is based on fitting a physically consistent cloud model to satellite observations simultaneously from the visible to the mid-infrared, thereby ensuring that the resulting cloud properties provide both a good representation of the short-wave and long-wave radiative effects of the observed cloud. The advantages of the optimal estimation method are that it enables rigorous error propagation and the inclusion of all measurements and any a priori information and associated errors in a rigorous mathematical framework. The algorithm provides a measure of the consistency between retrieval representation of cloud and satellite radiances. The cloud parameters retrieved are the cloud top pressure, cloud optical depth, cloud effective radius, cloud fraction and cloud phase.

    The algorithm can be applied to most visible/infrared satellite instruments. In this paper, we demonstrate the applicability to the Along-Track Scanning Radiometers ATSR-2 and AATSR. Examples of applying the algorithm to ATSR-2 flight data are presented and the sensitivity of the retrievals assessed, in particular the algorithm is evaluated for a number of simulated single-layer and multi-layer conditions. The algorithm was found to perform well for single-layer cloud except when the cloud was very thin; i.e., less than 1 optical depths. For the multi-layer cloud, the algorithm was robust except when the upper ice cloud layer is less than five optical depths. In these cases the retrieved cloud top pressure and cloud effective radius become a weighted average of the 2 layers. The sum of optical depth of multi-layer cloud is retrieved well until the cloud becomes thick

  14. A Benchmark Evaluation of Fault Tolerant Wind Turbine Control Concepts

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Stoustrup, Jakob

    2015-01-01

    As the world’s power supply to a larger and larger degree depends on wind turbines, it is consequently and increasingly important that these are as reliable and available as possible. Modern fault tolerant control (FTC) could play a substantial part in increasing reliability of modern wind turbin...... accommodation is handled in software sensor and actuator blocks. This means that the wind turbine controller can continue operation as in the fault free case. The other two evaluated solutions show some potential but probably need improvements before industrial applications....

  15. Conception, synthesis, and biological evaluation of original discodermolide analogues.

    Science.gov (United States)

    de Lemos, Elsa; Agouridas, Evangelos; Sorin, Geoffroy; Guerreiro, Antonio; Commerçon, Alain; Pancrazi, Ange; Betzer, Jean-François; Lannou, Marie-Isabelle; Ardisson, Janick

    2011-08-29

    Due to its intriguing biological activity profile and potential chemotherapeutic application discodermolide (DDM) proved to be an attractive target. Therefore, notable efforts have been carried out directed toward its total synthesis and toward the production and evaluation of synthetic analogues. Recently, we achieved the total synthesis of DDM. At the present, guided by the knowledge gained during our DDM total synthesis and by the requirement of keeping the bioactive "U" shape conformation, we report the convergent preparation of five original analogues. Three types of changes were realized through modification of the terminal (Z)-diene moiety, of the methyl group at the C14-position, and the lactone region. All analogues were active in the nanomolar range and two of them turned out to be equipotent to DDM.

  16. BeiDou Inter-Satellite-Type Bias Evaluation and Calibration for Mixed Receiver Attitude Determination

    Directory of Open Access Journals (Sweden)

    Noor Raziq

    2013-07-01

    Full Text Available The Chinese BeiDou system (BDS, having different types of satellites, is an important addition to the ever growing system of Global Navigation Satellite Systems (GNSS. It consists of Geostationary Earth Orbit (GEO satellites, Inclined Geosynchronous Satellite Orbit (IGSO satellites and Medium Earth Orbit (MEO satellites. This paper investigates the receiver-dependent bias between these satellite types, for which we coined the name “inter-satellite-type bias” (ISTB, and its impact on mixed receiver attitude determination. Assuming different receiver types may have different delays/biases for different satellite types, we model the differential ISTBs among three BeiDou satellite types and investigate their existence and their impact on mixed receiver attitude determination. Our analyses using the real data sets from Curtin’s GNSS array consisting of different types of BeiDou enabled receivers and series of zero-baseline experiments with BeiDou-enabled receivers reveal the existence of non-zero ISTBs between different BeiDou satellite types. We then analyse the impact of these biases on BeiDou-only attitude determination using the constrained (C-LAMBDA method, which exploits the knowledge of baseline length. Results demonstrate that these biases could seriously affect the integer ambiguity resolution for attitude determination using mixed receiver types and that a priori correction of these biases will dramatically improve the success rate.

  17. The use of concept mapping in measurement development and evaluation: Application and future directions.

    Science.gov (United States)

    Rosas, Scott R; Ridings, John W

    2017-02-01

    The past decade has seen an increase of measurement development research in social and health sciences that featured the use of concept mapping as a core technique. The purpose, application, and utility of concept mapping have varied across this emerging literature. Despite the variety of uses and range of outputs, little has been done to critically review how researchers have approached the application of concept mapping in the measurement development and evaluation process. This article focuses on a review of the current state of practice regarding the use of concept mapping as methodological tool in this process. We systematically reviewed 23 scale or measure development and evaluation studies, and detail the application of concept mapping in the context of traditional measurement development and psychometric testing processes. Although several limitations surfaced, we found several strengths in the contemporary application of the method. We determined concept mapping provides (a) a solid method for establishing content validity, (b) facilitates researcher decision-making, (c) insight into target population perspectives that are integrated a priori, and (d) a foundation for analytical and interpretative choices. Based on these results, we outline how concept mapping can be situated in the measurement development and evaluation processes for new instrumentation.

  18. Cloud retrievals from satellite data using optimal estimation: evaluation and application to ATSR

    Directory of Open Access Journals (Sweden)

    C. A. Poulsen

    2011-04-01

    Full Text Available Clouds play an important role in balancing the Earth's radiation budget. Clouds reflect sunlight which cools the Earth, and also trap infrared radiation in the same manner as greenhouse gases. Changes in cloud cover and cloud properties over time can have important consequences for climate. The Intergovernmental Panel for Climate Change (IPCC has identified current gaps in the understanding of clouds and related climate feedback processes as a leading cause of uncertainty in forecasting climate change. In this paper we present an algorithm that uses optimal estimation to retrieve cloud parameters from satellite multi-spectral imager data, in particular the Along-Track Scanning Radiometers ATSR-2 and AATSR. The cloud parameters retrieved are the cloud top pressure, cloud optical depth, cloud effective radius, cloud fraction and cloud phase. Importantly, the technique also provides estimated errors along with the retrieved values and quantifies the consistency between retrieval representation of cloud and satellite radiances. This should enable the effective use of the products for comparison with climate models or for exploitation via data assimilation. The technique is evaluated by performing retrieval simulations for a variety of simulated single layer and multi-layer conditions. Examples of applying the algorithm to ATSR-2 flight data are presented and the sensitivity of the retrievals assessed. This algorithm has been applied to both ATSR-2 and AATSR visible and infrared measurements in the context of the GRAPE (Global Retrieval and cloud Product Evaluation project to produce a 14 year consistent record for climate research (Sayer et al., 2010.

  19. Hydrologic evaluation of a Generalized Statistical Uncertainty Model for Satellite Precipitation Products

    Science.gov (United States)

    Sarachi, S.; Hsu, K. L.; Sorooshian, S.

    2014-12-01

    Development of satellite based precipitation retrieval algorithms and using them in hydroclimatic studies have been of great interest to hydrologists. It is important to understand the uncertainty associated with precipitation products and how they further contribute to the variability in stream flow simulation. In this study a mixture model of Generalized Normal Distribution and Gamma distribution (GND-G) is used to model the joint probability distribution of satellite-based (PERSIANN) and stage IV radar rainfall. The study area for constructing the uncertainty model covers a 15°×15°box of 0.25°×0.25° cells over the eastern United States for summer 2004 to 2009. Cells are aggregated in space and time to obtain data with different resolutions for the construction of the model's parameter space. This uncertainty model is evaluated using data from National Weather Service (NWS) Distributed Hydrologic Model Intercomparison Project - Phase 2 (DMIP 2) basin over Illinois River basin south of Siloam, OK. This data covers the time period of 2006 to 2008.The uncertainty range of precipitation is estimated. The impact of precipitation uncertainty to the stream flow estimation is demonstrated by Monte Carlo simulation of precipitation forcing in the Sacramento Soil Moisture Accounting (SAC-SMA) model. The results show that using precipitation along with its uncertainty distribution as forcing to SAC-SMA make it possible to have an estimation of the uncertainty associated with the stream flow simulation ( in this case study %90 confidence interval is used). The mean of this stream flow confidence interval is compared to the reference stream flow for evaluation of the model and the results show that this method helps to better estimate the variability of the stream flow simulation along with its statistics e.g. percent bias and root mean squared error.

  20. Evaluation of GISS SCM Simulated Cloud and Radiative Properties Using Both Surface and Satellite Observations

    Science.gov (United States)

    Kennedy, A. D.; Dong, X.; Xi, B.; Del Genio, A.; Wolf, A.; Minnis, P.; Khaiyer, M.; Doelling, D.; Nordeen, M.; Keyes, D.

    2009-05-01

    To evaluate the GISS SCM simulated cloud fractions, three years of surface and GOES satellite data have been collected at DOE ARM Southern Great Plains (SGP) site during 1999-2001. The GOES derived total and high cloud fractions from both 0.5° and 2.5° grid boxes are in excellent agreement with surface observations, suggesting that the ARM point observations can represent large areal observations. Compared to the ARM radar-lidar observed cloud fractions, the SCM simulated most mid-level clouds, overestimated low clouds, and underestimated total and high clouds with additional missed during the summer season. Further studies have revealed that the model simulated cloud fractions are strongly dependent on the large-scale synoptic pattern and its associated variables such as vertical motion and relative humidity. Because a significant amount of clouds over ARM SGP occur during synoptically quiescent conditions, the model has issues producing enough high cloud cover. This work suggests that alterations need to be made to the stratiform cloud scheme to better represent the sub-grid scale cloud variability in this case. The model simulated radiation budget is also evaluated with two years of collocated ARM surface radiation and CERES and GOES TOA radiation over the SGP site during March 2000-Dec. 2001. For this comparison, the model simulated surface and TOA radiation budgets agree well with surface and satellite observations (˜10 W m-2). Model simulated cloud optical depth, however, is about an order of magnitude higher than CERES/GOES retrievals, which may explain why the radiation budget is reasonable and yet total cloud fraction has a negative bias compared to observations. Further study is warranted to better understand how this impacts cloud radiative forcing.

  1. A Novel Satellite Mission Concept for Upper Air Water Vapour, Aerosol and Cloud Observations Using Integrated Path Differential Absorption LiDAR Limb Sounding

    Directory of Open Access Journals (Sweden)

    Claudia Weitnauer

    2012-03-01

    Full Text Available We propose a new satellite mission to deliver high quality measurements of upper air water vapour. The concept centres around a LiDAR in limb sounding by occultation geometry, designed to operate as a very long path system for differential absorption measurements. We present a preliminary performance analysis with a system sized to send 75 mJ pulses at 25 Hz at four wavelengths close to 935 nm, to up to 5 microsatellites in a counter-rotating orbit, carrying retroreflectors characterized by a reflected beam divergence of roughly twice the emitted laser beam divergence of 15 µrad. This provides water vapour profiles with a vertical sampling of 110 m; preliminary calculations suggest that the system could detect concentrations of less than 5 ppm. A secondary payload of a fairly conventional medium resolution multispectral radiometer allows wide-swath cloud and aerosol imaging. The total weight and power of the system are estimated at 3 tons and 2,700 W respectively. This novel concept presents significant challenges, including the performance of the lasers in space, the tracking between the main spacecraft and the retroreflectors, the refractive effects of turbulence, and the design of the telescopes to achieve a high signal-to-noise ratio for the high precision measurements. The mission concept was conceived at the Alpbach Summer School 2010.

  2. OTEC modular experiment cold water pipe concept evaluation. Volume III. Appendices

    Energy Technology Data Exchange (ETDEWEB)

    1979-04-01

    The Cold Water Pipe System Design Study was undertaken to evaluate the diverse CWP concepts, recommend the most viable alternatives for a 1984 deployment of the 10 to 40 MWe MEP, and carry out preliminary designs of three concepts. The concept evaluation phase reported involved a systems analysis of design alternatives in the broad categories of rigid walled (with hinges), compliant walled, stockade and bottom mounted buoyant. Quantitative evaluations were made of concept performance, availability, deployment schedule, technical feasibility and cost. CWP concepts were analyzed to determine if they met or could be made to meet established system requirements and could be deployed by 1984. Fabrication, construction and installation plans were developed for successful concepts, and costs were determined in a WBS format. Evaluations were performed on the basis of technical and cost risk. This volume includes the following appendices: (A) materials and associated design criteria; (B) summary of results of dynamic flow and transportation analysis; (C) CWP sizing analysis; (D) CWP thermal performance; and (E) investigation of the APL/ABAM CWP design. (WHK)

  3. OTEC modular experiment: cold water pipe concept evaluation. Volume II. Technical report

    Energy Technology Data Exchange (ETDEWEB)

    1979-04-01

    The Cold Water Pipe System Design Study was undertaken to evaluate the diverse CWP concepts, recommend the most viable alternatives for a 1984 deployment of the 10 to 40 MWe MEP, and carry out preliminary designs of three concepts. The Concept Evaluation Phase reported here involved a systems analysis of design alternatives in the broad categories of rigid walled (with hinges), compliant walled, stockade and bottom mounted buoyant. Quantitative evaluations were made of concept performance, availability, deployment schedule, technical feasibility and cost. CWP concepts were analyzed to determine if they met or could be made to meet established system requirements and could be deployed by 1984. Those which faced overwhelming technical and/or scheduling problems were rejected. Those which were unviable due to isolated, crucial technical and/or scheduling problems for which a technical development may reverse the decisions were deferred. Fabrication, construction and installation plans were developed for successful concepts, and costs were determined in a WBS format. Evaluations were performed on the basis of technical and cost risk. (WHK)

  4. Evaluation and Application of Satellite-Based Latent Heating Profile Estimation Methods

    Science.gov (United States)

    Olson, William S.; Grecu, Mircea; Yang, Song; Tao, Wei-Kuo

    2004-01-01

    In recent years, methods for estimating atmospheric latent heating vertical structure from both passive and active microwave remote sensing have matured to the point where quantitative evaluation of these methods is the next logical step. Two approaches for heating algorithm evaluation are proposed: First, application of heating algorithms to synthetic data, based upon cloud-resolving model simulations, can be used to test the internal consistency of heating estimates in the absence of systematic errors in physical assumptions. Second, comparisons of satellite-retrieved vertical heating structures to independent ground-based estimates, such as rawinsonde-derived analyses of heating, provide an additional test. The two approaches are complementary, since systematic errors in heating indicated by the second approach may be confirmed by the first. A passive microwave and combined passive/active microwave heating retrieval algorithm are evaluated using the described approaches. In general, the passive microwave algorithm heating profile estimates are subject to biases due to the limited vertical heating structure information contained in the passive microwave observations. These biases may be partly overcome by including more environment-specific a priori information into the algorithm s database of candidate solution profiles. The combined passive/active microwave algorithm utilizes the much higher-resolution vertical structure information provided by spaceborne radar data to produce less biased estimates; however, the global spatio-temporal sampling by spaceborne radar is limited. In the present study, the passive/active microwave algorithm is used to construct a more physically-consistent and environment-specific set of candidate solution profiles for the passive microwave algorithm and to help evaluate errors in the passive algorithm s heating estimates. Although satellite estimates of latent heating are based upon instantaneous, footprint- scale data, suppression

  5. Concept and analytical basis for revistas - A fast, flexible computer/graphic system for generating periodic satellite coverage patterns

    Science.gov (United States)

    King, J. C.

    1976-01-01

    The generation of satellite coverage patterns is facilitated by three basic strategies: use of a simplified physical model, permitting rapid closed-form calculation; separation of earth rotation and nodal precession from initial geometric analyses; and use of symmetries to construct traces of indefinite length by repetitive transposition of basic one-quadrant elements. The complete coverage patterns generated consist of a basic nadir trace plus a number of associated off-nadir traces, one for each sensor swath edge to be delineated. Each trace is generated by transposing one or two of the basic quadrant elements into a circle on a nonrotating earth model sphere, after which the circle is expanded into the actual 'helical' pattern by adding rotational displacements to the longitude coordinates. The procedure adapts to the important periodic coverage cases by direct insertion of the characteristic integers N and R (days and orbital revolutions, respectively, per coverage period).

  6. Concept and analytical basis for revistas - A fast, flexible computer/graphic system for generating periodic satellite coverage patterns

    Science.gov (United States)

    King, J. C.

    1976-01-01

    The generation of satellite coverage patterns is facilitated by three basic strategies: use of a simplified physical model, permitting rapid closed-form calculation; separation of earth rotation and nodal precession from initial geometric analyses; and use of symmetries to construct traces of indefinite length by repetitive transposition of basic one-quadrant elements. The complete coverage patterns generated consist of a basic nadir trace plus a number of associated off-nadir traces, one for each sensor swath edge to be delineated. Each trace is generated by transposing one or two of the basic quadrant elements into a circle on a nonrotating earth model sphere, after which the circle is expanded into the actual 'helical' pattern by adding rotational displacements to the longitude coordinates. The procedure adapts to the important periodic coverage cases by direct insertion of the characteristic integers N and R (days and orbital revolutions, respectively, per coverage period).

  7. Combined evaluation of optical and microwave satellite dataset for soil moisture deficit estimation

    Science.gov (United States)

    Srivastava, Prashant K.; Han, Dawei; Islam, Tanvir; Singh, Sudhir Kumar; Gupta, Manika; Gupta, Dileep Kumar; Kumar, Pradeep

    2016-04-01

    Soil moisture is a key variable responsible for water and energy exchanges from land surface to the atmosphere (Srivastava et al., 2014). On the other hand, Soil Moisture Deficit (or SMD) can help regulating the proper use of water at specified time to avoid any agricultural losses (Srivastava et al., 2013b) and could help in preventing natural disasters, e.g. flood and drought (Srivastava et al., 2013a). In this study, evaluation of Moderate Resolution Imaging Spectroradiometer (MODIS) Land Surface Temperature (LST) and soil moisture from Soil Moisture and Ocean Salinity (SMOS) satellites are attempted for prediction of Soil Moisture Deficit (SMD). Sophisticated algorithm like Adaptive Neuro Fuzzy Inference System (ANFIS) is used for prediction of SMD using the MODIS and SMOS dataset. The benchmark SMD estimated from Probability Distributed Model (PDM) over the Brue catchment, Southwest of England, U.K. is used for all the validation. The performances are assessed in terms of Nash Sutcliffe Efficiency, Root Mean Square Error and the percentage of bias between ANFIS simulated SMD and the benchmark. The performance statistics revealed a good agreement between benchmark and the ANFIS estimated SMD using the MODIS dataset. The assessment of the products with respect to this peculiar evidence is an important step for successful development of hydro-meteorological model and forecasting system. The analysis of the satellite products (viz. SMOS soil moisture and MODIS LST) towards SMD prediction is a crucial step for successful hydrological modelling, agriculture and water resource management, and can provide important assistance in policy and decision making. Keywords: Land Surface Temperature, MODIS, SMOS, Soil Moisture Deficit, Fuzzy Logic System References: Srivastava, P.K., Han, D., Ramirez, M.A., Islam, T., 2013a. Appraisal of SMOS soil moisture at a catchment scale in a temperate maritime climate. Journal of Hydrology 498, 292-304. Srivastava, P.K., Han, D., Rico

  8. Analyzing Concept Maps as an Assessment (Evaluation Tool in Teaching Mathematics

    Directory of Open Access Journals (Sweden)

    Ahmet S.   Ozdemir

    2005-01-01

    Full Text Available In this research concept mapping has been used as a testing instrument. In our country’s education system, the relationship between the scores which are given to concept maps and the scores which are given to traditional written exams and multiple choice examinations in teaching mathematics, has been analyzed. Especially the examinations about functions, numbers, exponent numbers, rooted numbers and absolute values have been evaluated. Literature class scores which are assumed to reflect the student’s oral thinking and their ability to express their thoughts have been compared with concept mapping’s scores. At the end of the research, it is understood that someone can make reliable testing and evaluation by using concept mapping. There is no meaningful correlation between concept mapping and multiple choice type examinations. On the other hand, there is a meaningful correlation between the scores of concept mapping and traditional mathematics examinations. About p<0.1 meaningfulness has been determined between concept mapping testing and literature examinations. In this research comments have been made on these results and various suggestions have been given according to these results.

  9. Satellite communication engineering

    CERN Document Server

    Kolawole, Michael Olorunfunmi

    2013-01-01

    An undeniably rich and thorough guide to satellite communication engineering, Satellite Communication Engineering, Second Edition presents the fundamentals of information communications systems in a simple and succinct way. This book considers both the engineering aspects of satellite systems as well as the practical issues in the broad field of information transmission. Implementing concepts developed on an intuitive, physical basis and utilizing a combination of applications and performance curves, this book starts off with a progressive foundation in satellite technology, and then moves on

  10. Evaluating Fault Management Operations Concepts for Next-Generation Spacecraft: What Eye Movements Tell Us

    Science.gov (United States)

    Hayashi, Miwa; Ravinder, Ujwala; McCann, Robert S.; Beutter, Brent; Spirkovska, Lily

    2009-01-01

    Performance enhancements associated with selected forms of automation were quantified in a recent human-in-the-loop evaluation of two candidate operational concepts for fault management on next-generation spacecraft. The baseline concept, called Elsie, featured a full-suite of "soft" fault management interfaces. However, operators were forced to diagnose malfunctions with minimal assistance from the standalone caution and warning system. The other concept, called Besi, incorporated a more capable C&W system with an automated fault diagnosis capability. Results from analyses of participants' eye movements indicate that the greatest empirical benefit of the automation stemmed from eliminating the need for text processing on cluttered, text-rich displays.

  11. Object-based Evaluation of Satellite Precipitation Retrievals: A Case Study of the Summer Season over CONUS

    Science.gov (United States)

    Li, J.; Xu, P.

    2015-12-01

    Satellite precipitation retrievals that have high spatial and temporal resolutions are suitable for various applications, such as hydrologic modeling and watershed management. Many validation studies have been established to understand the strengths and limitations of these satellite precipitation retrievals. In this study, an object-based validation approach is adopted to evaluate several satellite precipitation retrievals focusing on the spatial and geometric patterns of precipitation. This object-based validation approach identifies precipitation objects using an image processing technique referred to as watershed transform. Several object attributes are diagnosed and analyzed based on the distance measurement. Three object-based verification scores are summarized to determine the overall performances of satellite precipitation retrievals. The Integrated Multi-satellitE Retrievals for GPM (IMERG) and Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks (PERSIANN) were evaluated using the object-based approach. The NOAA stage IV MPE multi-sensor composite rain analysis was utilized as the ground observations. The comparative assessments were conducted at 0.25° by 0.25° on a daily scale in the summer season of 2014 over the continental United States (CONUS). The results suggest that IMERG possesses the similar spatial pattern of local-scale precipitation areas against stage IV observations. In addition, IMERG depicts the sizes and locations of precipitation areas more accurately against stage IV.

  12. Evaluation of the shortwave cloud radiative effect over the ocean by use of ship and satellite observations

    Directory of Open Access Journals (Sweden)

    T. Hanschmann

    2012-12-01

    Full Text Available In this study the shortwave cloud radiative effect (SWCRE over ocean calculated by the ECHAM 5 climate model is evaluated for the cloud property input derived from ship based measurements and satellite based estimates and compared to ship based radiation measurements. The ship observations yield cloud fraction, liquid water path from a microwave radiometer, cloud bottom height as well as temperature and humidity profiles from radiosonde ascents. Level-2 products of the Satellite Application Facility on Climate Monitoring (CM~SAF from the Spinning Enhanced Visible and InfraRed Imager (SEVIRI have been used to characterize clouds. Within a closure study six different experiments have been defined to find the optimal set of measurements to calculate downward shortwave radiation (DSR and the SWCRE from the model, and their results have been evaluated under seven different synoptic situations. Four of these experiments are defined to investigate the advantage of including the satellite-based cloud droplet effective radius as additional cloud property. The modeled SWCRE based on satellite retrieved cloud properties has a comparable accuracy to the modeled SWCRE based on ship data. For several cases, an improvement through introducing the satellite-based estimate of effective radius as additional information to the ship based data was found. Due to their different measuring characteristics, however, each dataset shows best results for different atmospheric conditions.

  13. Evaluating water storage variations in the MENA region using GRACE satellite data

    KAUST Repository

    Lopez, Oliver

    2013-12-01

    Terrestrial water storage (TWS) variations over large river basins can be derived from temporal gravity field variations observed by the Gravity Recovery and Climate Experiment (GRACE) satellites. These signals are useful for determining accurate estimates of water storage and fluxes over areas covering a minimum of 150,000 km2 (length scales of a few hundred kilometers) and thus prove to be a valuable tool for regional water resources management, particularly for areas with a lack of in-situ data availability or inconsistent monitoring, such as the Middle East and North Africa (MENA) region. This already stressed arid region is particularly vulnerable to climate change and overdraft of its non-renewable freshwater sources, and thus direction in managing its resources is a valuable aid. An inter-comparison of different GRACE-derived TWS products was done in order to provide a quantitative assessment on their uncertainty and their utility for diagnosing spatio-temporal variability in water storage over the MENA region. Different processing approaches for the inter-satellite tracking data from the GRACE mission have resulted in the development of TWS products, with resolutions in time from 10 days to 1 month and in space from 0.5 to 1 degree global gridded data, while some of them use input from land surface models in order to restore the original signal amplitudes. These processing differences and the difficulties in recovering the mass change signals over arid regions will be addressed. Output from the different products will be evaluated and compared over basins inside the MENA region, and compared to output from land surface models.

  14. Fast Simulators for Satellite Cloud Optical Centroid Pressure Retrievals, 1. Evaluation of OMI Cloud Retrievals

    Science.gov (United States)

    Joiner, J.; Vasilkov, A.; Gupta, P.; Bhartia, P. K.; Veefkind, P.; Sneep, M.; de Haan, J.; Polonsky, I.; Spurr, R.

    2012-01-01

    The cloud Optical Centroid Pressure (OCP), also known as the effective cloud pressure, is a satellite-derived parameter that is commonly used in trace-gas retrievals to account for the effects of clouds on near-infrared through ultraviolet radiance measurements. Fast simulators are desirable to further expand the use of cloud OCP retrievals into the operational and climate communities for applications such as data assimilation and evaluation of cloud vertical structure in general circulation models. In this paper, we develop and validate fast simulators that provide estimates of the cloud OCP given a vertical profile of optical extinction. We use a pressure-weighting scheme where the weights depend upon optical parameters of clouds and/or aerosol. A cloud weighting function is easily extracted using this formulation. We then use fast simulators to compare two different satellite cloud OCP retrievals from the Ozone Monitoring Instrument (OMI) with estimates based on collocated cloud extinction profiles from a combination of CloudS at radar and MODIS visible radiance data. These comparisons are made over a wide range of conditions to provide a comprehensive validation of the OMI cloud OCP retrievals. We find generally good agreement between OMI cloud OCPs and those predicted by CloudSat. However, the OMI cloud OCPs from the two independent algorithms agree better with each other than either does with the estimates from CloudSat/MODIS. Differences between OMI cloud OCPs and those based on CloudSat/MODIS may result from undetected snow/ice at the surface, cloud 3-D effects, low altitude clouds missed by CloudSat, and the fact that CloudSat only observes a relatively small fraction of an OMI field-of-view.

  15. Fast simulators for satellite cloud optical centroid pressure retrievals; evaluation of OMI cloud retrievals

    Directory of Open Access Journals (Sweden)

    J. Joiner

    2012-03-01

    Full Text Available The cloud Optical Centroid Pressure (OCP is a satellite-derived parameter that is commonly used in trace-gas retrievals to account for the effects of clouds on near-infrared through ultraviolet radiance measurements. Fast simulators are desirable to further expand the use of cloud OCP retrievals into the operational and climate communities for applications such as data assimilation and evaluation of cloud vertical structure in general circulation models. In this paper, we develop and validate fast simulators that provide estimates of the cloud OCP given a vertical profile of optical extinction. We use a pressure-weighting scheme where the weights depend upon optical parameters of clouds and/or aerosols. A cloud weighting function is easily extracted using this formulation. We then use fast simulators to compare two different satellite cloud OCP retrievals, from the Ozone Monitoring Instrument (OMI, with estimates based on collocated cloud extinction profiles from a combination of CloudSat radar and MODIS visible radiance data. These comparisons are made over a wide range of conditions to provide a comprehensive validation of the OMI cloud OCP retrievals. We find generally good agreement between OMI cloud OCPs and those predicted by CloudSat. However, the OMI cloud OCPs from the two independent algorithms agree better with each other than either does with the estimates from CloudSat/MODIS. Differences between OMI cloud OCPs and those based on CloudSat/MODIS may result from undetected snow/ice at the surface, cloud 3-D effects, cases of low clouds obscurred by ground-clutter in CloudSat observations and by opaque high clouds in CALIPSO lidar observations, and the fact that CloudSat/CALIPSO only observes a relatively small fraction of an OMI field-of-view.

  16. An Evaluation of Antarctica as a Calibration Target for Passive Microwave Satellite Missions

    Science.gov (United States)

    Kim, Edward

    2012-01-01

    Passive microwave remote sensing at L-band (1.4 GHz) is sensitive to soil moisture and sea surface salinity, both important climate variables. Science studies involving these variables can now take advantage of new satellite L-band observations. The first mission with regular global passive microwave observations at L-band is the European Space Agency's Soil Moisture and Ocean Salinity (SMOS), launched November, 2009. A second mission, NASA's Aquarius, was launched June, 201l. A third mission, NASA's Soil Moisture Active Passive (SMAP) is scheduled to launch in 2014. Together, these three missions may provide a decade-long data record -- provided that they are intercalibrated. The intercalibration is best performed at the radiance (brightness temperature) level, and Antarctica is proving to be a key calibration target. However, Antarctica has thus far not been fully characterized as a potential target. This paper will present evaluations of Antarctica as a microwave calibration target for the above satellite missions. Preliminary analyses have identified likely target areas, such as the vicinity of Dome-C and larger areas within East Antarctica. Physical sources of temporal and spatial variability of polar firn are key to assessing calibration uncertainty. These sources include spatial variability of accumulation rate, compaction, surface characteristics (dunes, micro-topography), wind patterns, and vertical profiles of density and temperature. Using primarily SMOS data, variability is being empirically characterized and attempts are being made to attribute observed variability to physical sources. One expected outcome of these studies is the potential discovery of techniques for remotely sensing--over all of Antarctica--parameters such as surface temperature.

  17. Evaluating Water Storage Variations in the MENA region using GRACE Satellite Data

    Science.gov (United States)

    Lopez, O.; Houborg, R.; McCabe, M. F.

    2013-12-01

    Terrestrial water storage (TWS) variations over large river basins can be derived from temporal gravity field variations observed by the Gravity Recovery and Climate Experiment (GRACE) satellites. These signals are useful for determining accurate estimates of water storage and fluxes over areas covering a minimum of 150,000 km2 (length scales of a few hundred kilometers) and thus prove to be a valuable tool for regional water resources management, particularly for areas with a lack of in-situ data availability or inconsistent monitoring, such as the Middle East and North Africa (MENA) region. This already stressed arid region is particularly vulnerable to climate change and overdraft of its non-renewable freshwater sources, and thus direction in managing its resources is a valuable aid. An inter-comparison of different GRACE-derived TWS products was done in order to provide a quantitative assessment on their uncertainty and their utility for diagnosing spatio-temporal variability in water storage over the MENA region. Different processing approaches for the inter-satellite tracking data from the GRACE mission have resulted in the development of TWS products, with resolutions in time from 10 days to 1 month and in space from 0.5 to 1 degree global gridded data, while some of them use input from land surface models in order to restore the original signal amplitudes. These processing differences and the difficulties in recovering the mass change signals over arid regions will be addressed. Output from the different products will be evaluated and compared over basins inside the MENA region, and compared to output from land surface models.

  18. Experimental evaluation of self-calibrating cavity radiometers for use in earth flux radiation balance measurements from satellites

    Science.gov (United States)

    Hickey, J. R.; Karoli, A. R.; Alton, B. M.

    1982-01-01

    A method for evaluating out-of-field response of wide-field, earth-viewing satellite radiometers is described. The equipment which simulates the earth and space consists of a central blackbody surrounded by a cooled ring. The radiometric and orbital considerations are discussed. Some test results for prototype ERBE cavity sensors are included. This presentation is restricted to longwave radiative transfer

  19. Methods of Evaluating Thermodynamic Properties of Landscape Cover Using Multispectral Reflected Radiation Measurements by the Landsat Satellite

    Directory of Open Access Journals (Sweden)

    Yuriy Puzachenko

    2013-09-01

    Full Text Available The paper discusses methods of evaluating thermodynamic properties of landscape cover based on multi-spectral measurements by the Landsat satellites. Authors demonstrate how these methods could be used for studying functionality of landscapes and for spatial interpolation of Flux NET system measurements.

  20. Site-level evaluation of satellite-based global terrestrial gross primary production and net primary production monitoring.

    Science.gov (United States)

    David P. Turner; William D. Ritts; Warren B. Cohen; Thomas K. Maeirsperger; Stith T. Gower; Al A. Kirschbaum; Steve W. Runnings; Maosheng Zhaos; Steven C. Wofsy; Allison L. Dunn; Beverly E. Law; John L. Campbell; Walter C. Oechel; Hyo Jung Kwon; Tilden P. Meyers; Eric E. Small; Shirley A. Kurc; John A. Gamon

    2005-01-01

    Operational monitoring of global terrestrial gross primary production (GPP) and net primary production (NPP) is now underway using imagery from the satellite-borne Moderate Resolution Imaging Spectroradiometer (MODIS) sensor. Evaluation of MODIS GPP and NPP products will require site-level studies across a range of biomes, with close attention to numerous scaling...

  1. Improved concepts and methods in analysis and evaluation of the urban climate for optimizing urban planning processes

    Science.gov (United States)

    Scherer, D.; Fehrenbach, U.; Beha, H.-D.; Parlow, E.

    Planning processes are strongly influenced by an increased awareness of environmental issues concerned by projected land-use transformations. A research project was carried out to produce climate maps for the region of Basel/Switzerland to enable planning authorities taking care of the urban climate and its interrelations with urban structures. Main focus was given to develop and implement a methodology meeting not only the regional requirements of Basel. The new approach is not depending on subjective criteria or manual interventions and ensures its applicability for other regions. Three basic concepts were developed or improved in this study. A new definition of `climatopes' was introduced, and methods were developed for their digital determination by objective criteria. This definition of climatopes requires adequate information on land-use, which is provided by introducing the concept of `areal types'. In contrast to `traditional' land-use classes directly derived from satellite images, areal types are complex aggregates reflecting not only different physical surface properties, but also socioeconomic aspects of land-use. `Ventilation classes' are the second component required to delineate climatopes. They summarize the combined influencing factors of terrain features and land-use structures on wind field and urban ventilation. Their determination is based on topographic information and surface properties derived from a digital terrain model and from land-use data. The spatial distribution of climatopes was computed for Basel. Various quality assessment procedures and the application of climatopes for an automated generation of planning guidelines demonstrate the applicability of the concepts. Climate maps containing the results of the analysis and evaluation of the urban climate of Basel were estimated by the involved planners to be a valuable tool meeting their practical requirements to a high degree.

  2. IDENTIFICATION OF BASES FOR EVALUATION OF THE BUSINESS EXCELLENCE STATUS IN RELATION TO THE CSR CONCEPT

    Directory of Open Access Journals (Sweden)

    Miriam Jankalová

    2017-06-01

    Full Text Available The process of globalization has started the need to achieve the Business Excellence status. Emphasizing the responsibility of the company's behaviour towards society and the environment is confirmed by the adoption of the concept of corporate social responsibility (CSR. Based on theoretical background review, there is no single unified methodology for the evaluation of the Business Excellence status in relation to the CSR concept. The aim of this paper is to identify bases for the evaluation of Business Excellence status in relation to the CSR concept. The most important tasks include: to identify internal and external factors affecting Business Excellence status; to identify CSR areas for the needs of evaluation of the Business Excellence status. Primary sources included especially national and foreign scientific publications.

  3. Satellites, Plasmas and Law: The Role of TeleCourt in Changing Conceptions of Justice and Authority in Ethiopia

    Directory of Open Access Journals (Sweden)

    Zenebe Beyene

    2015-05-01

    Full Text Available An ambitious experiment in the ICT and justice sector is underway in Ethiopia. As part of an effort to improve service delivery and the responsiveness of the state, the Ethiopian government has created 'TeleCourt,' a system that allows trials to take place between remote areas and regional or federal courts through videoconferencing and a satellite Internet connection. This article is the first to analyze how TeleCourt operates, with a particular focus on the perspectives of end-users, those who have had first-hand experience of how 'justice at a distance' actually works. The findings suggest general satisfaction with the savings - both in terms of financial burden and time costs that are often incurred when travelling to trials - which TeleCourt allows. As the system improves ways to provide justice to the grassroots, in line with the government's commitment towards peasants, this must also be considered in the context of the Ethiopian government's growing efforts to use law to curb political dissent. This is indicative of a broader tendency of selectively adopting and reshaping ICTs and extending them to the poorest people in Ethiopia in order to support the functioning of the state, while other uses of ICTs that are seen as potentially destabilizing are discouraged or forbidden.

  4. Concept of a small satellite for sub-MeV and MeV all sky survey: the CAST mission

    Science.gov (United States)

    Nakazawa, Kazuhiro; Takahashi, Tadayuki; Ichinohe, Yuto; Takeda, Shin'ichiro; Tajima, Hiroyasu; Kamae, Tuneyoshi; Kokubun, Motohide; Takashima, Takeshi; Tashiro, Makoto; Tamagawa, Toru; Terada, Yukikatsu; Nomachi, Masaharu; Fukazawa, Yasushi; Makishima, Kazuo; Mizuno, Tsunefumi; Mitani, Takefumi; Yoshimitsu, Tetsuo; Watanabe, Shin

    2012-09-01

    MeV and sub-MeV energy band from ~200 keV to ~2 MeV contains rich information of high-energy phenomena in the universe. The CAST (Compton Telescope for Astro and Solar Terrestrial) mission is planned to be launched at the end of 2010s, and aims at providing all-sky map in this energy-band for the first time. It is made of a semiconductor Compton telescope utilizing Si as a scatterer and CdTe as an absorber. CAST provides allsky sub-MeV polarization map for the first time, as well. The Compton telescope technology is based on the design used in the Soft Gamma-ray Detector (SGD) onboard ASTRO-H, characterized by its tightly stacked semiconductor layers to obtain high Compton reconstruction efficiency. The CAST mission is currently planned as a candidate for the small scientific satellite series in ISAS/JAXA, weighting about 500 kg in total. Scalable detector design enables us to consider other options as well. Scientific outcome of CAST is wide. It will provide new information from high-energy sources, such as AGN and/or its jets, supernova remnants, magnetors, blackhole and neutron-star binaries and others. Polarization map will tell us about activities of jets and reflections in these sources, as well. In addition, CAST will simultaneously observe the Sun, and depending on its attitude, the Earth.

  5. Evaluation of Satellite Precipitation and Hydrological Model Predictions for Flood Events Over The Guadalupe River Basin, Texas

    Science.gov (United States)

    Sharif, H. O.; Furl, C.

    2016-12-01

    In this study, we evaluate the quality of several satellite precipitation products in comparison to gauge corrected ground based radar estimaties for moderate to high magnitude events across the Guadalupe River system in south Texas. The analysis is conducted across four partially nested watersheds (200-10,000 km2) such that scale effects can also be examined. Additionally, the precipitation data sets are used as input to the fully-distributed, physics-based Gridded Surface Subsurface Hydrologic Analysis (GSSHA) model to examine rainfall error propagation through the hydrologic model predictions. Both gauge corrected and uncorrected satellite products are used encompassing a variety of latent delivery times, spatial resolutions, and temporal resolutions. Satellite precipitation datasets used in the study include various products from GPM, the Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks (PERSIANN) system, the NOAA CPC Morphing Technique (CMORPH), and the Tropical Rainfall Measuring Mission (TRMM).

  6. Evaluation of Empirical Tropospheric Models Using Satellite-Tracking Tropospheric Wet Delays with Water Vapor Radiometer at Tongji, China

    OpenAIRE

    Miaomiao Wang; Bofeng Li

    2016-01-01

    An empirical tropospheric delay model, together with a mapping function, is commonly used to correct the tropospheric errors in global navigation satellite system (GNSS) processing. As is well-known, the accuracy of tropospheric delay models relies mainly on the correction efficiency for tropospheric wet delays. In this paper, we evaluate the accuracy of three tropospheric delay models, together with five mapping functions in wet delays calculation. The evaluations are conducted by comparing ...

  7. On the Evaluation of Gnss Complementary by Using Quasizenith Satellite of Japan

    Science.gov (United States)

    Sekiguchi, N.; Shikada, M.; Kanai, T.

    2016-06-01

    The positional information has an important role in our lifestyle. People need to get positional information by GNSS. The satellite positioning must receive a signal from four or more satellites, however, most of Japanese country is covered with mountain and urban area has a lot of tall buildings. Then Japanese government launched QZS (Quasi Zenith Satellite) which is the first satellite of QZSS (Quasi Zenith Satellite System) in 2010. QZSS including QZS can improve positioning accuracy and reliability. QZS has 6 signals by using four kinds of frequency. These signals are the same frequency of GPS and GLONASS and so on. This paper was reported about the comparison of the positioning between GPS and QZSS.

  8. Evaluation concepts to compare observed and simulated deposition areas of mass movements

    Science.gov (United States)

    Heiser, Micha; Scheidl, Christian; Kaitna, Roland

    2017-04-01

    A delineation of potentially endangered areas by geophysical mass flows, like debris flows, rock and snow avalanches, is an important for regional and urban planning. For this numerical simulation programs have become an important tool in engineering hazard assessment. However, when being confronted with the evaluation of model performance and sensitivity there are no standard, objective approaches. In this contribution we present a new approach to quantitatively compare 2D simulations of observed and simulated deposition patterns - a concept derived from a literature review of 75 peer reviewed articles which inverse modelled real events of different types of mass flows. It seems that existing evaluation concepts with respect to the deposition distribution does only account for one or a combination of two possible evaluation errors based on overestimation, underestimation and/or overlap of the simulation outcome with the observed reference. The proposed evaluation concept integrates all three possible errors and yields a single metric between -1 (no fit) and 1 (perfect fit). Combined with a ternary plot we further show that the proposed evaluation concept might act as a simple decision support tool to i) identify weaknesses and strengths of the simulation model, ii) to find the best simulation setup and iii) to test whether higher complexity of simulation models are balanced by higher accuracies. This method shall help developers and end-users of simulation models to better understand model behavior and provide a possibility for comparison of model results, independent of simulation platform and type of mass flow.

  9. EFFECTIVENESS OF CONCEPT MAPPING IN DEVELOPING INFORMATION SEARCH AND EVALUATION SKILLS

    Directory of Open Access Journals (Sweden)

    Ivette Maldonado Rivera

    2016-02-01

    Full Text Available To determine the effectiveness of concept mapping in developing information skills, through non-probability sampling technique were selected 30 students enrolled in a Management course at the University of Puerto Rico at Bayamon during the academic year 2012-2013. A quantitative research approach and a quasi-experimental design was used. The students participated in an instructional unit on searching and evaluating information, based on concept maps. To determine student learning a test was used as a pre and posttest. To know the opinion of students on the strategy implemented an opinion questionnaire was administered. Because there was a significant increase in the arithmetic means of the posttest when compared with average pretest it was concluded that concept maps represent an effective strategy for learning skills of finding and evaluating information.

  10. Concepts for evaluation of sound insulation of dwellings - from chaos to consensus?

    DEFF Research Database (Denmark)

    Rasmussen, Birgit; Rindel, Jens Holger

    2005-01-01

    Legal sound insulation requirements have existed more than 50 years in some countries, and single-number quantities for evaluation of sound insulation have existed nearly as long time. However, the concepts have changed considerably over time from simple arithmetic averaging of frequency bands....... The concepts suitable for evaluation should be well-defined under practical situations in buil¬dings, be measurable, reproducible and of course correlate well with subjective evalua¬tion. More noise sources - incl. neighbours’ activities - and an increased demand for high quality and comfort together...... with a trend towards light-weight constructions are contradictory and challenging. This calls for exchange of data and experience, implying a need for harmonized concepts, including use of spectrum adaptation terms. The paper will provide input for future discussions in EAA TC-RBA WG4: "Sound insulation...

  11. Evaluation of Satellite Retrievals of Ocean Chlorophyll-a in the California Current

    Directory of Open Access Journals (Sweden)

    Mati Kahru

    2014-09-01

    Full Text Available Retrievals of ocean surface chlorophyll-a concentration (Chla by multiple ocean color satellite sensors (SeaWiFS, MODIS-Terra, MODIS-Aqua, MERIS, VIIRS using standard algorithms were evaluated in the California Current using a large archive of in situ measurements. Over the full range of in situ Chla, all sensors produced a coefficient of determination (R2 between 0.79 and 0.88 and a median absolute percent error (MdAPE between 21% and 27%. However, at in situ Chla > 1 mg m−3, only products from MERIS (both the ESA produced algal_1 and NASA produced chlor_a maintained reasonable accuracy (R2 from 0.74 to 0.52 and MdAPE from 23% to 31%, respectively, while the other sensors had R2 below 0.5 and MdAPE higher than 36%. We show that the low accuracy at medium and high Chla is caused by the poor retrieval of remote sensing reflectance.

  12. Evaluating a satellite-based seasonal evapotranspiration product and identifying its relationship with other satellite-derived products and crop yield: A case study for Ethiopia

    Science.gov (United States)

    Tadesse, Tsegaye; Senay, Gabriel B.; Berhan, Getachew; Regassa, Teshome; Beyene, Shimelis

    2015-01-01

    Satellite-derived evapotranspiration anomalies and normalized difference vegetation index (NDVI) products from Moderate Resolution Imaging Spectroradiometer (MODIS) data are currently used for African agricultural drought monitoring and food security status assessment. In this study, a process to evaluate satellite-derived evapotranspiration (ETa) products with a geospatial statistical exploratory technique that uses NDVI, satellite-derived rainfall estimate (RFE), and crop yield data has been developed. The main goal of this study was to evaluate the ETa using the NDVI and RFE, and identify a relationship between the ETa and Ethiopia’s cereal crop (i.e., teff, sorghum, corn/maize, barley, and wheat) yields during the main rainy season. Since crop production is one of the main factors affecting food security, the evaluation of remote sensing-based seasonal ETa was done to identify the appropriateness of this tool as a proxy for monitoring vegetation condition in drought vulnerable and food insecure areas to support decision makers. The results of this study showed that the comparison between seasonal ETa and RFE produced strong correlation (R2 > 0.99) for all 41 crop growing zones in Ethiopia. The results of the spatial regression analyses of seasonal ETa and NDVI using Ordinary Least Squares and Geographically Weighted Regression showed relatively weak yearly spatial relationships (R2 cropping zones. However, for each individual crop zones, the correlation between NDVI and ETa ranged between 0.3 and 0.84 for about 44% of the cropping zones. Similarly, for each individual crop zones, the correlation (R2) between the seasonal ETa anomaly and de-trended cereal crop yield was between 0.4 and 0.82 for 76% (31 out of 41) of the crop growing zones. The preliminary results indicated that the ETa products have a good predictive potential for these 31 identified zones in Ethiopia. Decision makers may potentially use ETa products for monitoring cereal crop yields and

  13. ThermoData engine (TDE): software implementation of the dynamic data evaluation concept. 4. Chemical reactions.

    Science.gov (United States)

    Diky, Vladimir; Chirico, Robert D; Kazakov, Andrei F; Muzny, Chris D; Frenkel, Michael

    2009-12-01

    ThermoData Engine (TDE) is the first full-scale software implementation of the dynamic data evaluation concept, as reported recently in this journal. This paper describes the first application of this concept to the evaluation of thermodynamic properties for chemical reactions. Reaction properties evaluated are the enthalpies, entropies, Gibbs energies, and thermodynamic equilibrium constants. Details of key considerations in the critical evaluation of enthalpies of formation and of standard entropies for organic compounds are discussed in relation to their application in the calculation of reaction properties. Extensions to the class structure of the program are described that allow close linkage between the derived reaction properties and the underlying pure-component properties. Derivation of pure-component enthalpies of formation and of standard entropies through the use of directly measured reaction properties (enthalpies of reaction and equilibrium constants) is described. Directions for future enhancements are outlined.

  14. Evaluation of satellite and reanalysis-based global net surface energy flux and uncertainty estimates

    Science.gov (United States)

    Allan, Richard; Liu, Chunlei

    2017-04-01

    The net surface energy flux is central to the climate system yet observational limitations lead to substantial uncertainty (Trenberth and Fasullo, 2013; Roberts et al., 2016). A combination of satellite-derived radiative fluxes at the top of atmosphere (TOA) adjusted using the latest estimation of the net heat uptake of the Earth system, and the atmospheric energy tendencies and transports from the ERA-Interim reanalysis are used to estimate surface energy flux globally (Liu et al., 2015). Land surface fluxes are adjusted through a simple energy balance approach using relations at each grid point with the consideration of snowmelt to improve regional realism. The energy adjustment is redistributed over the oceans using a weighting function to avoid meridional discontinuities. Uncertainties in surface fluxes are investigated using a variety of approaches including comparison with a range of atmospheric reanalysis input data and products. Zonal multiannual mean surface flux uncertainty is estimated to be less than 5 Wm-2 but much larger uncertainty is likely for regional monthly values. The meridional energy transport is calculated using the net surface heat fluxes estimated in this study and the result shows better agreement with observations in Atlantic than before. The derived turbulent fluxes (difference between the net heat flux and the CERES EBAF radiative flux at surface) also have good agreement with those from OAFLUX dataset and buoy observations. Decadal changes in the global energy budget and the hemisphere energy imbalances are quantified and present day cross-equator heat transports is re-evaluated as 0.22±0.15 PW southward by the atmosphere and 0.32±0.16 PW northward by the ocean considering the observed ocean heat sinks (Roemmich et al., 2006) . Liu et al. (2015) Combining satellite observations and reanalysis energy transports to estimate global net surface energy fluxes 1985-2012. J. Geophys. Res., Atmospheres. ISSN 2169-8996 doi: 10.1002/2015JD

  15. Program Evaluation on the Implementation of a Middle School Concept in Private Christian Schools

    Science.gov (United States)

    Hall, James Chapman

    2015-01-01

    The purpose of this study was to determine the level of implementing a middle school concept in three private Christian schools using Daniel Stufflebeam's CIPP model of program evaluation. The National Middle School Survey was used to measure faculty and administrative perceptions of both the value and actual implementation of middle school…

  16. Innovative Access Programme for Young Mothers Wishing to Train in Childbirth Education: From Concept to Evaluation

    Science.gov (United States)

    Nolan, Mary L.

    2008-01-01

    This paper describes the conception, planning, implementation and evaluation of an access programme arising out of an innovative collaboration between two charities, Straight Talking and the National Childbirth Trust. The access programme was designed at the request of a group of young mothers who had finished compulsory education and subsequently…

  17. Differences in Stakeholder Perceptions about Training Evaluation: A Concept Mapping/Pattern Matching Investigation.

    Science.gov (United States)

    Michalski, Greg V.; Cousins, J. Bradley

    2000-01-01

    Used concept mapping and pattern matching in exploratory research to investigate differences in stakeholder perceptions of training results and evaluation. Group perceptions and the individual perceptions of 39 managers, product developers, and training professionals show that all stakeholder groups agreed reasonably well about the importance of…

  18. An Examination of the Concept and Role of Program Monitoring and Evaluation.

    Science.gov (United States)

    Sherwood-Fabre, Liese

    This paper examines the concepts of program monitoring and program evaluation in the literature, and offers working definitions based on two dimensions of measurement: focus (what questions are addressed) and timing (how often the measures are taken). Focus can be on inputs to the program or outcomes from it; timing can be one-shot or continuous.…

  19. Linking Health Concepts in the Assessment and Evaluation of Water Distribution Systems

    Science.gov (United States)

    Karney, Bryan W.; Filion, Yves R.

    2005-01-01

    The concept of health is not only a specific criterion for evaluation of water quality delivered by a distribution system but also a suitable paradigm for overall functioning of the hydraulic and structural components of the system. This article views health, despite its complexities, as the only criterion with suitable depth and breadth to allow…

  20. Evaluation of the latest satellite-gauge precipitation products and their hydrologic applications over the Huaihe River basin

    Science.gov (United States)

    Sun, Ruochen; Yuan, Huiling; Liu, Xiaoli; Jiang, Xiaoman

    2016-05-01

    Satellite-gauge quantitative precipitation estimate (QPE) products may reduce the errors in near real-time satellite precipitation estimates by combining rain gauge data, which provides great potential to hydrometeorological applications. This study aims to comprehensively evaluate four of the latest satellite-gauge QPEs, including NASA's Tropical Rainfall Measuring Mission (TRMM) 3B42V7 product, NOAA's Climate Prediction Center (CPC) MORPHing technique (CMORPH) bias-corrected product (CMORPH CRT), CMORPH satellite-gauge merged product (CMORPH BLD) and CMORPH satellite-gauge merged product developed at the National Meteorological Information Center (NMIC) of the China Meteorological Administration (CMA) (CMORPH CMA). These four satellite-gauge QPEs are statistically evaluated over the Huaihe River basin during 2003-2012 and applied into the distributed Variable Infiltration Capacity (VIC) model to assess hydrologic utilities. Compared to the China Gauge-based Daily Precipitation Analysis (CGDPA) newly developed at CMA/NMIC, the four satellite-gauge QPEs generally depict the spatial distribution well, with the underestimation in the southern mountains and overestimation in the northern plain of the Huaihe River basin. Specifically, both TRMM and CMORPH CRT adopt simple gauge adjustment algorithms and exhibit relatively poor performance, with evidently deteriorated quality in winter. In contrast, the probability density function-optimal interpolation (PDF-OI) gauge adjustment procedure has been applied in CMORPH BLD and CMORPH CMA, resulting in higher quality and more stable performance. CMORPH CMA further benefits from a merged dense gauge observation network and outperforms the other QPEs with significant improvements in rainfall amount and spatial/temporal distributions. Due to the insufficient gauge observations in the merging process, CMORPH BLD features the similar error characteristics of CMORPH CRT with a positive bias of light precipitation and a negative

  1. Evaluation of satellite based indices for gross primary production estimates in a sparse savanna in the Sudan

    Directory of Open Access Journals (Sweden)

    M. Sjöström

    2009-01-01

    Full Text Available One of the more frequently applied methods for integrating controls on primary production through satellite data is the Light Use Efficiency (LUE approach. Satellite indices such as the Normalized Difference Vegetation Index (NDVI, Enhanced Vegetation Index (EVI and the Shortwave Infrared Water Stress Index (SIWSI have previously shown promise as predictors of primary production in several different environments. In this study, we evaluate NDVI, EVI and SIWSI derived from the Moderate Resolution Imaging Spectroradiometer (MODIS satellite sensor against in-situ measurements from central Sudan in order to asses their applicability in LUE-based primary production modeling within a water limited environment. Results show a strong correlation between vegetation indices and gross primary production (GPP, demonstrating the significance of vegetation indices for deriving information on primary production with relatively high accuracy at similar areas. Evaluation of SIWSI however, reveal that the fraction of vegetation apparently is to low for the index to provide accurate information on canopy water content, indicating that the use of SIWSI as a predictor of water stress in satellite data-driven primary production modeling in similar semi-arid ecosystems is limited.

  2. Multicenter evaluation of different target volume delineation concepts in pediatric Hodgkin's lymphoma. A case study.

    Science.gov (United States)

    Lütgendorf-Caucig, C; Fotina, I; Gallop-Evans, E; Claude, L; Lindh, J; Pelz, T; Knäusl, B; Georg, D; Pötter, R; Dieckmann, K

    2012-11-01

    In pediatric Hodgkin's lymphoma (PHL) improvements in imaging and multiagent chemotherapy have allowed for a reduction in target volume. The involved-node (IN) concept is being tested in several treatment regimens for adult Hodgkin's lymphoma. So far there is no consensus on the definition of the IN. To improve the reproducibility of the IN, we tested a new involved-node-level (INL) concept, using defined anatomical boundaries as basis for target delineation. The aim was to evaluate the feasibility of IN and INL concepts for PHL in terms of interobserver variability. The INL concept was defined for the neck and mediastinum by the PHL Radiotherapy Group based on accepted concepts for solid tumors. Seven radiation oncologists from six European centers contoured neck and mediastinal clinical target volumes (CTVs) of 2 patients according to the IN and the new INL concepts. The median CTVs, coefficient of variation (COV), and general conformity index (CI) were assessed. The intraclass correlation coefficient (ICC) for reliability of delineations was calculated. All observers agreed that INL is a feasible and practicable delineation concept resulting in stronger interobserver concordance than the IN (mediastinum CI(INL) = 0.39 vs. CI(IN) = 0.28, neck left CI(INL) = 0.33; CI(IN) = 0.18; neck right CI(INL) = 0.24, CI(IN) = 0.14). The COV showed less dispersion and the ICC indicated higher reliability of contouring for INL (ICC(INL) = 0.62, p < 0.05) as for IN (ICC(IN) = 0.40, p < 0.05). INL is a practical and feasible alternative to IN resulting in more homogeneous target delineation, and it should be therefore considered as a future target volume concept in PHL.

  3. A dynamic approach for evaluating coarse scale satellite soil moisture products

    Directory of Open Access Journals (Sweden)

    A. Loew

    2010-09-01

    Full Text Available Validating coarse scale remote sensing soil moisture products requires a comparison of gridded data to point-like ground measurements. The necessary aggregation of in situ measurements to the footprint scale of a satellite sensor (>100 km2 introduces uncertainties in the validation of the satellite soil moisture product. Observed differences between the satellite product and in situ data are therefore partly attributable to these aggregation uncertainties. The present paper investigates different approaches to disentangle the error of the satellite product from the uncertainties associated to the up-scaling of the reference data. A novel approach is proposed, which allows for the quantification of the remote sensing soil moisture error using a temporally adaptive technique. It is shown that the point-to-area sampling error can be estimated within 0.0084 [m3/m3].

  4. APPLICABILITY EVALUATION OF OBJECT DETECTION METHOD TO SATELLITE AND AERIAL IMAGERIES

    Directory of Open Access Journals (Sweden)

    K. Kamiya

    2016-06-01

    Full Text Available Since satellite and aerial imageries are recently widely spread and frequently observed, combination of them are expected to complement spatial and temporal resolution each other. One of the prospective applications is traffic monitoring, where objects of interest, or vehicles, need to be recognized automatically. Techniques that employ object detection before object recognition can save a computational time and cost, and thus take a significant role. However, there is not enough knowledge whether object detection method can perform well on satellite and aerial imageries. In addition, it also has to be studied how characteristics of satellite and aerial imageries affect the object detection performance. This study employ binarized normed gradients (BING method that runs significantly fast and is robust to rotation and noise. For our experiments, 11-bits BGR-IR satellite imageries from WorldView-3, and BGR-color aerial imageries are used respectively, and we create thousands of ground truth samples. We conducted several experiments to compare the performances with different images, to verify whether combination of different resolution images improved the performance, and to analyze the applicability of mixing satellite and aerial imageries. The results showed that infrared band had little effect on the detection rate, that 11-bit images performed less than 8-bit images and that the better spatial resolution brought the better performance. Another result might imply that mixing higher and lower resolution images for training dataset could help detection performance. Furthermore, we found that aerial images improved the detection performance on satellite images.

  5. Applicability Evaluation of Object Detection Method to Satellite and Aerial Imageries

    Science.gov (United States)

    Kamiya, K.; Fuse, T.; Takahashi, M.

    2016-06-01

    Since satellite and aerial imageries are recently widely spread and frequently observed, combination of them are expected to complement spatial and temporal resolution each other. One of the prospective applications is traffic monitoring, where objects of interest, or vehicles, need to be recognized automatically. Techniques that employ object detection before object recognition can save a computational time and cost, and thus take a significant role. However, there is not enough knowledge whether object detection method can perform well on satellite and aerial imageries. In addition, it also has to be studied how characteristics of satellite and aerial imageries affect the object detection performance. This study employ binarized normed gradients (BING) method that runs significantly fast and is robust to rotation and noise. For our experiments, 11-bits BGR-IR satellite imageries from WorldView-3, and BGR-color aerial imageries are used respectively, and we create thousands of ground truth samples. We conducted several experiments to compare the performances with different images, to verify whether combination of different resolution images improved the performance, and to analyze the applicability of mixing satellite and aerial imageries. The results showed that infrared band had little effect on the detection rate, that 11-bit images performed less than 8-bit images and that the better spatial resolution brought the better performance. Another result might imply that mixing higher and lower resolution images for training dataset could help detection performance. Furthermore, we found that aerial images improved the detection performance on satellite images.

  6. High Resolution Visualization Applied to Future Heavy Airlift Concept Development and Evaluation

    Science.gov (United States)

    FordCook, A. B.; King, T.

    2012-01-01

    This paper explores the use of high resolution 3D visualization tools for exploring the feasibility and advantages of future military cargo airlift concepts and evaluating compatibility with existing and future payload requirements. Realistic 3D graphic representations of future airlifters are immersed in rich, supporting environments to demonstrate concepts of operations to key personnel for evaluation, feedback, and development of critical joint support. Accurate concept visualizations are reviewed by commanders, platform developers, loadmasters, soldiers, scientists, engineers, and key principal decision makers at various stages of development. The insight gained through the review of these physically and operationally realistic visualizations is essential to refining design concepts to meet competing requirements in a fiscally conservative defense finance environment. In addition, highly accurate 3D geometric models of existing and evolving large military vehicles are loaded into existing and proposed aircraft cargo bays. In this virtual aircraft test-loading environment, materiel developers, engineers, managers, and soldiers can realistically evaluate the compatibility of current and next-generation airlifters with proposed cargo.

  7. Evaluating greenhouse gas emissions inventories for agricultural burning using satellite observations of active fires.

    Science.gov (United States)

    Lin, Hsiao-Wen; Jin, Yufang; Giglio, Louis; Foley, Jonathan A; Randerson, James T

    2012-06-01

    Fires in agricultural ecosystems emit greenhouse gases and aerosols that influence climate on multiple spatial and temporal scales. Annex 1 countries of the United Nations Framework Convention on Climate Change (UNFCCC), many of which ratified the Kyoto Protocol, are required to report emissions of CH4 and N2O from these fires annually. In this study, we evaluated several aspects of this reporting system, including the optimality of the crops targeted by the UNFCCC globally and within Annex 1 countries, and the consistency of emissions inventories among different countries. We also evaluated the success of individual countries in capturing interannual variability and long-term trends in agricultural fire activity. In our approach, we combined global high-resolution maps of crop harvest area and production, derived from satellite maps and ground-based census data, with Terra and Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) measurements of active fires. At a global scale, we found that adding ground nuts (e.g., peanuts), cocoa, cotton and oil palm, and removing potato, oats, rye, and pulse other from the list of 14 crops targeted by the UNFCCC increased the percentage of active fires covered by the reporting system by 9%. Optimization led to a different recommended list for Annex 1 countries, requiring the addition of sunflower, cotton, rapeseed, and alfalfa and the removal of beans, sugarcane, pulse others, and tuber-root others. Extending emissions reporting to all Annex 1 countries (from the current set of 19 countries) would increase the efficacy of the reporting system from 6% to 15%, and further including several non-Annex 1 countries (Argentina, Brazil, China, India, Indonesia, Thailand, Kazakhstan, Mexico, and Nigeria) would capture over 55% of active fires in croplands worldwide. Analyses of interannual trends from the United States and Australia showed the importance of both intensity of fire use and crop production in controlling year

  8. Evaluation of ACCMIP Outgoing Longwave Radiation from Tropospheric Ozone Using TES Satellite Observations.

    Science.gov (United States)

    Bowman, Kevin W.; Shindell, Drew Todd; Worden, H. M.; Lamarque, J. F.; Young, P. J.; Stevenson, D. S.; Qu, Z.; delaTorre, M.; Bergmann, D.; Cameron-Smith, P. J.; Collins, W. J.; Doherty, R.; Dalsoren, S. B.; Faluvegi, G.; Folberth, G.; Horowitz, L. W.; Josse, B. M.; Lee, Y. H.; MacKenzie, I. A.; Myhre, G.; Nagashima, T.; Naik, V.; Strode, S. A.; Kulawik, S. S..; Worden, J. R.

    2013-01-01

    We use simultaneous observations of tropospheric ozone and outgoing longwave radiation (OLR) sensitivity to tropospheric ozone from the Tropospheric Emission Spectrometer (TES) to evaluate model tropospheric ozone and its effect on OLR simulated by a suite of chemistry-climate models that participated in the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP). The ensemble mean of ACCMIP models show a persistent but modest tropospheric ozone low bias (5-20 ppb) in the Southern Hemisphere (SH) and modest high bias (5-10 ppb) in the Northern Hemisphere (NH) relative to TES ozone for 2005-2010. These ozone biases have a significant impact on the OLR. Using TES instantaneous radiative kernels (IRK), we show that the ACCMIP ensemble mean tropospheric ozone low bias leads up to 120mW/ sq. m OLR high bias locally but zonally compensating errors reduce the global OLR high bias to 39+/- 41mW/ sq. m relative to TES data. We show that there is a correlation (Sq. R = 0.59) between the magnitude of the ACCMIP OLR bias and the deviation of the ACCMIP preindustrial to present day (1750-2010) ozone radiative forcing (RF) from the ensemble ozone RF mean. However, this correlation is driven primarily by models whose absolute OLR bias from tropospheric ozone exceeds 100mW/ sq. m. Removing these models leads to a mean ozone radiative forcing of 394+/- 42mW/ sq. m. The mean is about the same and the standard deviation is about 30% lower than an ensemble ozone RF of 384 +/- 60mW/ sq. m derived from 14 of the 16 ACCMIP models reported in a companion ACCMIP study. These results point towards a profitable direction of combining satellite observations and chemistry-climate model simulations to reduce uncertainty in ozone radiative forcing.

  9. Satellite data-based phenological evaluation of the nationwide reforestation of South Korea.

    Directory of Open Access Journals (Sweden)

    Su-Jong Jeong

    Full Text Available Through the past 60 years, forests, now of various age classes, have been established in the southern part of the Korean Peninsula through nationwide efforts to reestablish forests since the Korean War (1950-53, during which more than 65% of the nation's forest was destroyed. Careful evaluation of long-term changes in vegetation growth after reforestation is one of the essential steps to ensuring sustainable forest management. This study investigated nationwide variations in vegetation phenology using satellite-based growing season estimates for 1982-2008. The start of the growing season calculated from the normalized difference vegetation index (NDVI agrees reasonably with the ground-observed first flowering date both temporally (correlation coefficient, r = 0.54 and spatially (r = 0.64 at the 95% confidence level. Over the entire 27-year period, South Korea, on average, experienced a lengthening of the growing season of 4.5 days decade(-1, perhaps due to recent global warming. The lengthening of the growing season is attributed mostly to delays in the end of the growing season. The retrieved nationwide growing season data were used to compare the spatial variations in forest biomass carbon density with the time-averaged growing season length for 61 forests. Relatively higher forest biomass carbon density was observed over the regions having a longer growing season, especially for the regions dominated by young (<30 year forests. These results imply that a lengthening of the growing season related to the ongoing global warming may have positive impacts on carbon sequestration, an important aspect of large-scale forest management for sustainable development.

  10. Integrating satellite actual evapotranspiration patterns into distributed model parametrization and evaluation for a mesoscale catchment

    Science.gov (United States)

    Demirel, M. C.; Mai, J.; Stisen, S.; Mendiguren González, G.; Koch, J.; Samaniego, L. E.

    2016-12-01

    Distributed hydrologic models are traditionally calibrated and evaluated against observations of streamflow. Spatially distributed remote sensing observations offer a great opportunity to enhance spatial model calibration schemes. For that it is important to identify the model parameters that can change spatial patterns before the satellite based hydrologic model calibration. Our study is based on two main pillars: first we use spatial sensitivity analysis to identify the key parameters controlling the spatial distribution of actual evapotranspiration (AET). Second, we investigate the potential benefits of incorporating spatial patterns from MODIS data to calibrate the mesoscale Hydrologic Model (mHM). This distributed model is selected as it allows for a change in the spatial distribution of key soil parameters through the calibration of pedo-transfer function parameters and includes options for using fully distributed daily Leaf Area Index (LAI) directly as input. In addition the simulated AET can be estimated at the spatial resolution suitable for comparison to the spatial patterns observed using MODIS data. We introduce a new dynamic scaling function employing remotely sensed vegetation to downscale coarse reference evapotranspiration. In total, 17 parameters of 47 mHM parameters are identified using both sequential screening and Latin hypercube one-at-a-time sampling methods. The spatial patterns are found to be sensitive to the vegetation parameters whereas streamflow dynamics are sensitive to the PTF parameters. The results of multi-objective model calibration show that calibration of mHM against observed streamflow does not reduce the spatial errors in AET while they improve only the streamflow simulations. We will further examine the results of model calibration using only multi spatial objective functions measuring the association between observed AET and simulated AET maps and another case including spatial and streamflow metrics together.

  11. Simulation evaluation of TIMER, a time-based, terminal air traffic, flow-management concept

    Science.gov (United States)

    Credeur, Leonard; Capron, William R.

    1989-01-01

    A description of a time-based, extended terminal area ATC concept called Traffic Intelligence for the Management of Efficient Runway scheduling (TIMER) and the results of a fast-time evaluation are presented. The TIMER concept is intended to bridge the gap between today's ATC system and a future automated time-based ATC system. The TIMER concept integrates en route metering, fuel-efficient cruise and profile descents, terminal time-based sequencing and spacing together with computer-generated controller aids, to improve delivery precision for fuller use of runway capacity. Simulation results identify and show the effects and interactions of such key variables as horizon of control location, delivery time error at both the metering fix and runway threshold, aircraft separation requirements, delay discounting, wind, aircraft heading and speed errors, and knowledge of final approach speed.

  12. Evaluation of a Novel BEV Concept Based on Fixed and Swappable Li-Ion Battery Packs

    DEFF Research Database (Denmark)

    Barreras, Jorge Varela; Pinto, Claudio; de Castro, Ricardo;

    2016-01-01

    In this paper, a novel battery electric vehicle (BEV) concept based on a small fixed and a big swappable Li-ion battery pack is proposed in order to achieve longer range, lower initial purchase priceand lower energy consumption at short ranges. For short ranges, the BEV is only powered...... by the relatively small-fixed battery pack, without the large swappable battery pack. In this way, the mass of the vehicle is reduced and, therefore, the energy consumed per unit distance is improved. For higher ranges, the BEV is powered by both battery packs. This concept allows the introduction of subscription......-based ownership models to distribute the cost of the large battery pack over the vehicle lifetime. A methodology is proposed for the analysis and evaluation of the proposed concept in comparison with a direct owned nonswappable single-pack BEV, proving that significant improvements on city fuel economy (up to 14...

  13. 卫星成本风险分析与评估%Risk Analyzing and Evaluating of Satellite Engineering Cost

    Institute of Scientific and Technical Information of China (English)

    李一军; 王兆耀; 钱进

    2001-01-01

    Satellite engineering is a large-scale and complicated system engineer ing with longtime span, and varied indeterminate factors bring on very high risk of cost. It′s quite a problem to be solved urgently in the management of satel l ite developing that how the risk of satellite engineering cost can be evaluated effectively. It starts with analyzing the uncertainty of satellite cost and existed risk analysis methods, then on the base of it put forward a practica l and improved method adapted to the risk management of satellite cost. Finally this article presents the principle and method of reducing and controlling the r isk of cost.%从卫星成本不确定性分析入手,在已有的风险分析方法的基础上,针对卫星成本风险 管理的特点,提出了实用的改进方法,给出了降低和控制成本风险的原则和方法。

  14. Evaluation of GPM-based Multi-satellite IMERG Precipitation Products Over the Lower Colorado River Basin, Texas

    Science.gov (United States)

    Omranian, S. E.; Sharif, H. O.

    2016-12-01

    This study evaluates the Global Precipitation Measurement (GPM) satellite products by analyzing extreme rainfall events over the Lower Colorado River Basin, Texas that resulted in unprecedented flash floods in May 2015. Records of a dense rain gauge network (241 stations) are compared with Integrated Multi-satellite Retrievals for GPM (IMERG) products. The spatial resolution of the GPM satellite product is 0.1º x 0.1º and the temporal resolution is 30 minutes. Reference gauge-based observations are distributed through the basin with total area of over 5,000 square kilometers at 15-minute time intervals. A preliminary assessment of GPM-based IMERG precipitation products shows reasonable correlation, especially when for periods of high amounts of rainfall. the results indicate that GPM satellite products can potentially be employed in hydrologic modeling, especially for large events. Moreover, since the IMERG products have semi-global coverage, it can be extremely useful in hydrological modeling and analysis studies over ungauged or poorly gauged regions.

  15. Further Evaluation of a Satellite-based Real-time Global Flood Monitoring System

    Science.gov (United States)

    Wu, H.; Adler, R. F.; Tian, Y.; Hong, Y.; Policelli, F.

    2011-12-01

    A real-time global flood monitoring system (GFMS) driven by Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) rainfall was further developed with a relatively more physically based hydrological model. The performance in flood detection of this new version of the GFMS was evaluated against available flood event archives (Wu et al, 2011). This new GFMS is quantitatively evaluated in terms of flood event detection during the TRMM era (1998-2010) using a global retrospective simulation (3-hourly and 1/8 degree spatial resolution) with the TMPA 3B42V6 rainfall. Four methods were explored to define flood events from the model results, including three percentile-based statistic methods and a Log Pearson-III flood frequency curve method. The evaluation showed the GFMS detection performance improves with longer flood durations and larger affected areas. The impact of dams was detected in the validation statistics. The presence of dams tends to result in more false alarms and false alarm duration. The GFMS statistics for flood durations > 3 days and for areas without dams vary across the four identification methods, but center around a POD of ~ 0.70 and a FAR of ~ 0.65. When both flood events-based categorical verification metrics and flood duration metrics are considered, a method using the 95th percentile runoff depth plus two parameters related to variability and basin size (method 3) may be more suitable for application to our routine, real-time flood calculations. The evaluation showed the GFMS detection performance improves with longer flood durations and larger affected areas. The new GFMS (operationally available at http://trmm.gsfc.nasa.gov/) improved not only the flood detection performance, but also in the presentation of flood evolution (start, development and recession) in the drainage network. The new GFMS is further evaluated with more quantitative flood properties including flood peak timing, peak stage, peak volumes

  16. Evaluating the hydrological consistency of evaporation products using satellite-based gravity and rainfall data

    Science.gov (United States)

    López, Oliver; Houborg, Rasmus; McCabe, Matthew Francis

    2017-01-01

    Advances in space-based observations have provided the capacity to develop regional- to global-scale estimates of evaporation, offering insights into this key component of the hydrological cycle. However, the evaluation of large-scale evaporation retrievals is not a straightforward task. While a number of studies have intercompared a range of these evaporation products by examining the variance amongst them, or by comparison of pixel-scale retrievals against ground-based observations, there is a need to explore more appropriate techniques to comprehensively evaluate remote-sensing-based estimates. One possible approach is to establish the level of product agreement between related hydrological components: for instance, how well do evaporation patterns and response match with precipitation or water storage changes? To assess the suitability of this consistency-based approach for evaluating evaporation products, we focused our investigation on four globally distributed basins in arid and semi-arid environments, comprising the Colorado River basin, Niger River basin, Aral Sea basin, and Lake Eyre basin. In an effort to assess retrieval quality, three satellite-based global evaporation products based on different methodologies and input data, including CSIRO-PML, the MODIS Global Evapotranspiration product (MOD16), and Global Land Evaporation: the Amsterdam Methodology (GLEAM), were evaluated against rainfall data from the Global Precipitation Climatology Project (GPCP) along with Gravity Recovery and Climate Experiment (GRACE) water storage anomalies. To ensure a fair comparison, we evaluated consistency using a degree correlation approach after transforming both evaporation and precipitation data into spherical harmonics. Overall we found no persistent hydrological consistency in these dryland environments. Indeed, the degree correlation showed oscillating values between periods of low and high water storage changes, with a phase difference of about 2-3 months

  17. Evaluation of Airframe Noise Reduction Concepts via Simulations Using a Lattice Boltzmann Approach

    Science.gov (United States)

    Fares, Ehab; Casalino, Damiano; Khorrami, Mehdi R.

    2015-01-01

    Unsteady computations are presented for a high-fidelity, 18% scale, semi-span Gulfstream aircraft model in landing configuration, i.e. flap deflected at 39 degree and main landing gear deployed. The simulations employ the lattice Boltzmann solver PowerFLOW® to simultaneously capture the flow physics and acoustics in the near field. Sound propagation to the far field is obtained using a Ffowcs Williams and Hawkings acoustic analogy approach. In addition to the baseline geometry, which was presented previously, various noise reduction concepts for the flap and main landing gear are simulated. In particular, care is taken to fully resolve the complex geometrical details associated with these concepts in order to capture the resulting intricate local flow field thus enabling accurate prediction of their acoustic behavior. To determine aeroacoustic performance, the farfield noise predicted with the concepts applied is compared to high-fidelity simulations of the untreated baseline configurations. To assess the accuracy of the computed results, the aerodynamic and aeroacoustic impact of the noise reduction concepts is evaluated numerically and compared to experimental results for the same model. The trends and effectiveness of the simulated noise reduction concepts compare well with measured values and demonstrate that the computational approach is capable of capturing the primary effects of the acoustic treatment on a full aircraft model.

  18. ThermoData Engine (TDE): software implementation of the dynamic data evaluation concept. 3. Binary mixtures.

    Science.gov (United States)

    Diky, Vladimir; Chirico, Robert D; Kazakov, Andrei F; Muzny, Chris D; Frenkel, Michael

    2009-02-01

    ThermoData Engine (TDE) is the first full-scale software implementation of the dynamic data evaluation concept, as reported recently in this journal. The present paper describes the first application of this concept to the evaluation of thermophysical properties for binary chemical systems. Five activity-coefficient models have been implemented for representation of phase-equilibrium data (vapor-liquid, liquid-liquid, and solid-liquid equilibrium): NRTL, UNIQUAC, Van Laar, Margules/Redlich-Kister, and Wilson. Implementation of these models in TDE is fully described. Properties modeled individually are densities, surface tensions, critical temperatures, critical pressures, excess enthalpies, and the transport properties-viscosity and thermal conductivity. Extensions to the class structure of the program are described with emphasis on special features allowing close linkage between mixture and pure-component properties required for implementation of the models. Details of gas-phase models used in conjunction with the activity-coefficient models are shown. Initial implementation of the dynamic data evaluation concept for reactions is demonstrated with evaluation of enthalpies of formation for compounds containing carbon, hydrogen, oxygen, and nitrogen. Directions for future enhancements are outlined.

  19. Toward a Coherent Detailed Evaluation of Aerosol Data Products from Multiple Satellite Sensors

    Science.gov (United States)

    Ichoku, Charles; Petrenko, Maksym; Leptoukh, Gregory

    2011-01-01

    Atmospheric aerosols represent one of the greatest uncertainties in climate research. Although satellite-based aerosol retrieval has practically become routine, especially during the last decade, there is often disagreement between similar aerosol parameters retrieved from different sensors, leaving users confused as to which sensors to trust for answering important science questions about the distribution, properties, and impacts of aerosols. As long as there is no consensus and the inconsistencies are not well characterized and understood, there will be no way of developing reliable climate data records from satellite aerosol measurements. Fortunately, the most globally representative well-calibrated ground-based aerosol measurements corresponding to the satellite-retrieved products are available from the Aerosol Robotic Network (AERONET). To adequately utilize the advantages offered by this vital resource, an online Multi-sensor Aerosol Products Sampling System (MAPSS) was recently developed. The aim of MAPSS is to facilitate detailed comparative analysis of satellite aerosol measurements from different sensors (Terra-MODIS, Aqua-MODIS, TerraMISR, Aura-OMI, Parasol-POLDER, and Calipso-CALIOP) based on the collocation of these data products over AERONET stations. In this presentation, we will describe the strategy of the MASS system, its potential advantages for the aerosol community, and the preliminary results of an integrated comparative uncertainly analysis of aerosol products from multiple satellite sensors.

  20. Evaluation of Clear Sky Models for Satellite-Based Irradiance Estimates

    Energy Technology Data Exchange (ETDEWEB)

    Sengupta, M.; Gotseff, P.

    2013-12-01

    This report describes an intercomparison of three popular broadband clear sky solar irradiance model results with measured data, as well as satellite-based model clear sky results compared to measured clear sky data. The authors conclude that one of the popular clear sky models (the Bird clear sky model developed by Richard Bird and Roland Hulstrom) could serve as a more accurate replacement for current satellite-model clear sky estimations. Additionally, the analysis of the model results with respect to model input parameters indicates that rather than climatological, annual, or monthly mean input data, higher-time-resolution input parameters improve the general clear sky model performance.

  1. The City Intelligence Quotient (City IQ Evaluation System: Conception and Evaluation

    Directory of Open Access Journals (Sweden)

    Zhiqiang Wu

    2016-06-01

    Full Text Available After a systematic review of 38 current intelligent city evaluation systems (ICESs from around the world, this research analyzes the secondary and tertiary indicators of these 38 ICESs from the perspectives of scale structuring, approaches and indicator selection, and determines their common base. From this base, the fundamentals of the City Intelligence Quotient (City IQ Evaluation System are developed and five dimensions are selected after a clustering analysis. The basic version, City IQ Evaluation System 1.0, involves 275 experts from 14 high-end research institutions, which include the Chinese Academy of Engineering, the National Academy of Science and Engineering (Germany, the Royal Swedish Academy of Engineering Sciences, the Planning Management Center of the Ministry of Housing and Urban-Rural Development of China, and the Development Research Center of the State Council of China. City IQ Evaluation System 2.0 is further developed, with improvements in its universality, openness, and dynamic adjustment capability. After employing deviation evaluation methods in the IQ assessment, City IQ Evaluation System 3.0 was conceived. The research team has conducted a repeated assessment of 41 intelligent cities around the world using City IQ Evaluation System 3.0. The results have proved that the City IQ Evaluation System, developed on the basis of intelligent life, features more rational indicators selected from data sources that can offer better universality, openness, and dynamics, and is more sensitive and precise.

  2. Data-Intensive Evaluation: The Concept, Methods, and Prospects of Higher Education Monitoring Evaluation

    Science.gov (United States)

    Wang, Zhanjun; Qiao, Weifeng; Li, Jiangbo

    2016-01-01

    Higher education monitoring evaluation is a process that uses modern information technology to continually collect and deeply analyze relevant data, visually present the state of higher education, and provide an objective basis for value judgments and scientific decision making by diverse bodies Higher education monitoring evaluation is…

  3. Evaluation of combat service support logistics concepts for supplying a USMC Regimental Task Force

    OpenAIRE

    2001-01-01

    One of the primary responsibilities of a Marine Corps Combat Service Support Element (CSSE) is to provide water, fuel, and ammunition requirements for the primary task forces and other Marine Expeditionary Force (MEF) elements. This thesis evaluates existing and proposed concepts on how to best use the CSSE resources of a Force Service Support Group to transport supplies to Regimental Combat Teams over constrained networks with time constraints. A model was developed that optimizes the use of...

  4. Copability, coping, and learning as focal concepts in the evaluation of computerised diabetes disease management.

    Science.gov (United States)

    Boisen, Egil; Bygholm, Ann; Cavan, David; Hejlesen, Ole K

    2003-07-01

    Within diabetes care, the majority of health decisions are in the hands of the patient. Therefore, the concepts of disease management and self-care represent inescapable challenges for both patient and healthcare professionals, entailing a considerable amount of learning. Thus, a computerised diabetes disease management systems (CDDM) is to be seen not merely as tools for the medical treatment, but also as pedagogical tools to enhance patient competence. The unfortunate lack of success for most knowledge-based systems might be related to the problem of finding an adequate way of evaluating the systems from their development through the implementation phase to the daily clinical practice. The following presents the initial methodological considerations for evaluating the usefulness of a CDDM system called DiasNet, which is being implemented as a learning tool for patients. The evaluation of usefulness of a CDDM, we claim, entails clinical assessment taking into account the challenges and pitfalls in diabetes disease management. Drawing on activity theory, we suggest the concept of copability as a supplement to 'usability' and 'utility' when determining 'usefulness'. We maintain that it is necessary to ask how well the user copes with the new situation using the system. As ways to measure copability of DiasNet the concepts of coping and learning are discussed, as well as ways this methodology might inform systems development, implementation, and daily clinical practice.

  5. Experimental design for the evaluation of high-T(sub c) superconductive thermal bridges in a sensor satellite

    Science.gov (United States)

    Scott, Elaine P.; Lee, Kasey M.

    1994-01-01

    Infrared sensor satellites, which consist of cryogenic infrared sensor detectors, electrical instrumentation, and data acquisition systems, are used to monitor the conditions of the earth's upper atmosphere in order to evaluate its present and future changes. Currently, the electrical connections (instrumentation), which act as thermal bridges between the cryogenic infrared sensor and the significantly warmer data acquisition unit of the sensor satellite system, constitute a significant portion of the heat load on the cryogen. As a part of extending the mission life of the sensor satellite system, the researchers at the National Aeronautics and Space Administration's Langley Research Center (NASA-LaRC) are evaluating the effectiveness of replacing the currently used manganin wires with high-temperature superconductive (HTS) materials as the electrical connections (thermal bridges). In conjunction with the study being conducted at NASA-LaRC, the proposed research is to design a space experiment to determine the thermal savings on a cryogenic subsystem when manganin leads are replaced by HTS leads printed onto a substrate with a low thermal conductivity, and to determine the thermal conductivities of HTS materials. The experiment is designed to compare manganin wires with two different types of superconductors on substrates by determining the heat loss by the thermal bridges and providing temperature measurements for the estimation of thermal conductivity. A conductive mathematical model has been developed and used as a key tool in the design process and subsequent analysis.

  6. Applications of Satellite Remote Sensing Products to Enhance and Evaluate the AIRPACT Regional Air Quality Modeling System

    Science.gov (United States)

    Herron-Thorpe, F. L.; Mount, G. H.; Emmons, L. K.; Lamb, B. K.; Jaffe, D. A.; Wigder, N. L.; Chung, S. H.; Zhang, R.; Woelfle, M.; Vaughan, J. K.; Leung, F. T.

    2013-12-01

    The WSU AIRPACT air quality modeling system for the Pacific Northwest forecasts hourly levels of aerosols and atmospheric trace gases for use in determining potential health and ecosystem impacts by air quality managers. AIRPACT uses the WRF/SMOKE/CMAQ modeling framework, derives dynamic boundary conditions from MOZART-4 forecast simulations with assimilated MOPITT CO, and uses the BlueSky framework to derive fire emissions. A suite of surface measurements and satellite-based remote sensing data products across the AIRPACT domain are used to evaluate and improve model performance. Specific investigations include anthropogenic emissions, wildfire simulations, and the effects of long-range transport on surface ozone. In this work we synthesize results for multiple comparisons of AIRPACT with satellite products such as IASI ammonia, AIRS carbon monoxide, MODIS AOD, OMI tropospheric ozone and nitrogen dioxide, and MISR plume height. Features and benefits of the newest version of AIRPACT's web-interface are also presented.

  7. Transparent Gap Filler Solution over a DVB-RCS2 Satellite Platform in a Railway Scenario: Performance Evaluation Study

    Directory of Open Access Journals (Sweden)

    Peppino Fazio

    2015-01-01

    Full Text Available In this work, a performance study of a system equipped with a transparent Gap Filler solution in a DVB-RCS2 satellite platform has been provided. In particular, a simulation model based on a 3-state Markov chain, overcoming the blockage status through the introduction of a transparent Gap Filler (using devices on both tunnel sides has been implemented. The handover time, due to switching mechanism between satellite and Gap Filler, has been taken into account. As reference scenario, the railway market has been considered, which is characterized by a N-LOS condition, due to service disruptions caused by tunnels, vegetation and buildings. The system performance, in terms of end-to-end delay, queue size and packet loss percentage, have been evaluated, in order to prove the goodness of communications in a real railroad path.

  8. Evaluation of the Potential of NASA Multi-satellite Precipitation Analysis in Global Landslide Hazard Assessment

    Science.gov (United States)

    Hong, Yang; Adler, Robert F.; Huffman, George J.

    2007-01-01

    Landslides are one of the most widespread natural hazards on Earth, responsible for thousands of deaths and billions of dollars in property damage every year. In the U.S. alone landslides occur in every state, causing an estimated $2 billion in damage and 25- 50 deaths each year. Annual average loss of life from landslide hazards in Japan is 170. The situation is much worse in developing countries and remote mountainous regions due to lack of financial resources and inadequate disaster management ability. Recently, a landslide buried an entire village on the Philippines Island of Leyte on Feb 17,2006, with at least 1800 reported deaths and only 3 houses left standing of the original 300. Intense storms with high-intensity , long-duration rainfall have great potential to trigger rapidly moving landslides, resulting in casualties and property damage across the world. In recent years, through the availability of remotely sensed datasets, it has become possible to conduct global-scale landslide hazard assessment. This paper evaluates the potential of the real-time NASA TRMM-based Multi-satellite Precipitation Analysis (TMPA) system to advance our understanding of and predictive ability for rainfall-triggered landslides. Early results show that the landslide occurrences are closely associated with the spatial patterns and temporal distribution of rainfall characteristics. Particularly, the number of landslide occurrences and the relative importance of rainfall in triggering landslides rely on the influence of rainfall attributes [e.g. rainfall climatology, antecedent rainfall accumulation, and intensity-duration of rainstorms). TMPA precipitation data are available in both real-time and post-real-time versions, which are useful to assess the location and timing of rainfall-triggered landslide hazards by monitoring landslide-prone areas while receiving heavy rainfall. For the purpose of identifying rainfall-triggered landslides, an empirical global rainfall intensity

  9. Evaluation of Six High-Resolution Satellite and Ground-Based Precipitation Products over Malaysia

    Directory of Open Access Journals (Sweden)

    Mou Leong Tan

    2015-01-01

    Full Text Available Satellite precipitation products (SPPs potentially constitute an alternative to sparse rain gauge networks for assessing the spatial distribution of precipitation. However, applications of these products are still limited due to the lack of robust quality assessment. This study compares daily, monthly, seasonal, and annual rainfall amount at 342 rain gauges over Malaysia to estimations using five SPPs (3B42RT, 3B42V7, GPCP-1DD, PERSIANN-CDR, and CMORPH and a ground-based precipitation product (APHRODITE. The performance of the precipitation products was evaluated from 2003 to 2007 using continuous (RMSE, R2, ME, MAE, and RB and categorical (ACC, POD, FAR, CSI, and HSS statistical approaches. Overall, 3B42V7 and APHRODITE performed the best, while the worst performance was shown by GPCP-1DD. 3B42RT, 3B42V7, and PERSIANN-CDR slightly overestimated observed precipitation by 2%, 4.7%, and 2.1%, respectively. By contrast, APHRODITE and CMORPH significantly underestimated precipitations by 19.7% and 13.2%, respectively, whereas GPCP-1DD only slightly underestimated by 2.8%. All six precipitation products performed better in the northeast monsoon than in the southwest monsoon. The better performances occurred in eastern and southern Peninsular Malaysia and in the north of East Malaysia, which receives higher rainfall during the northeast monsoon, whereas poor performances occurred in the western and dryer Peninsular Malaysia. All precipitation products underestimated the no/tiny (<1 mm/day and extreme (≥20 mm/day rainfall events, while they overestimated low (1–20 mm/day rainfall events. 3B42RT and 3B42V7 showed the best ability to detect precipitation amounts with the highest HSS value (0.36. Precipitations during flood events such as those which occurred in late 2006 and early 2007 were estimated the best by 3B42RT and 3B42V7, as shown by an R2 value ranging from 0.49 to 0.88 and 0.52 to 0.86, respectively. These results on SPPs’ uncertainties

  10. Evaluation of Satellite and Ground Based Precipitation Products for Flood Forecasting

    Science.gov (United States)

    Chintalapudi, S.; Sharif, H.; Yeggina, S.

    2012-04-01

    The development in satellite-derived rainfall estimates encouraged the hydrological modeling in sparse gauged basins or ungauged basins. Especially, physically-based distributed hydrological models can benefit from the good spatial and temporal coverage of satellite precipitation products. In this study, three satellite derived precipitation datasets (TRMM, CMORPH, and PERSIANN), NEXRAD, and rain gauge precipitation datasets were used to drive the hydrological model. The physically-based, distributed hydrological model Gridded Surface Subsurface Hydrological Analysis (GSSHA) was used in this study. Focus will be on the results from the Guadalupe River Basin above Canyon Lake and below Comfort, Texas. The Guadalupe River Basin above Canyon Lake and below Comfort Texas drains an area of 1232 km2. Different storm events will be used in these simulations. August 2007 event was used as calibration and June 2007 event was used as validation. Results are discussed interms of accuracy of satellite precipitation estimates with the ground based precipitation estimates, predicting peak discharges, runoff volumes, time lag, and spatial distribution. The initial results showed that, model was able to predict the peak discharges and runoff volumes when using NEXRAD MPE data, and TRMM 3B42 precipitation product. The results also showed that there was time lag in hydrographs driven by both PERSIANN and CMORPH data sets.

  11. Evaluating global trends (1988-2010) in harmonized multi-satellite surface soil moisture

    NARCIS (Netherlands)

    Dorigo, W.A.; Jeu, de R.A.M.; Chung, D.; Parinussa, R.M.; Liu, Y.; Wagner, W.; Fernandez-Prieto, D.

    2012-01-01

    [1] Global trends in a new multi-satellite surface soil moisture dataset were analyzed for the period 1988–2010. 27% of the area covered by the dataset showed significant trends (p = 0.05). Of these, 73% were negative and 27% positive. Subtle drying trends were found in the Southern US, central Sout

  12. Evaluation of Satellite Rainfall Estimates for Drought and Flood Monitoring in Mozambique

    NARCIS (Netherlands)

    Tote, C.; Patricio, D.; Boogaard, H.L.; Wijngaart, van der R.; Tarnavsky, E.; Funk, C.

    2015-01-01

    Satellite derived rainfall products are useful for drought and flood early warning and overcome the problem of sparse, unevenly distributed and erratic rain gauge observations, provided their accuracy is well known. Mozambique is highly vulnerable to extreme weather events such as major droughts and

  13. Management Control Systems, Evaluative Style, and Behaviour : Exploring the Concept and Behavioural Consequences of Evaluative Style

    NARCIS (Netherlands)

    J. Noeverman (Jan)

    2007-01-01

    textabstractOrganisations develop and implement performance measurement and performance evaluation systems to motivate employees to take actions that -in the end- improve organisational (financial) performance. But do these systems really influence employee behaviour as intended? This thesis shows

  14. Management Control Systems, Evaluative Style, and Behaviour : Exploring the Concept and Behavioural Consequences of Evaluative Style

    NARCIS (Netherlands)

    J. Noeverman (Jan)

    2007-01-01

    textabstractOrganisations develop and implement performance measurement and performance evaluation systems to motivate employees to take actions that -in the end- improve organisational (financial) performance. But do these systems really influence employee behaviour as intended? This thesis shows

  15. ThermoData Engine (TDE) software implementation of the dynamic data evaluation concept. 7. Ternary mixtures.

    Science.gov (United States)

    Diky, Vladimir; Chirico, Robert D; Muzny, Chris D; Kazakov, Andrei F; Kroenlein, Kenneth; Magee, Joseph W; Abdulagatov, Ilmutdin; Kang, Jeong Won; Frenkel, Michael

    2012-01-23

    ThermoData Engine (TDE) is the first full-scale software implementation of the dynamic data evaluation concept, as reported in this journal. The present paper describes the first application of this concept to the evaluation of thermophysical properties for ternary chemical systems. The method involves construction of Redlich-Kister type equations for individual properties (excess volume, thermal conductivity, viscosity, surface tension, and excess enthalpy) and activity coefficient models for phase equilibrium properties (vapor-liquid and liquid-liquid equilibrium). Constructed ternary models are based on those for the three pure component and three binary subsystems evaluated on demand through the TDE software algorithms. All models are described in detail, and extensions to the class structure of the program are provided. Reliable evaluation of properties for the binary subsystems is essential for successful property evaluations for ternary systems, and algorithms are described to aid appropriate parameter selection and fitting for the implemented activity coefficient models (NRTL, Wilson, Van Laar, Redlich-Kister, and UNIQUAC). Two activity coefficient models based on group contributions (original UNIFAC and NIST-KT-UNIFAC) are also implemented. Novel features of the user interface are shown, and directions for future enhancements are outlined.

  16. Evaluation of the home-energy-rating concept and the Massachusetts Pilot Project

    Energy Technology Data Exchange (ETDEWEB)

    Frankel, M.L.; Duberg, J.A.

    1983-06-01

    This is a report on the results of an evaluation of a home-energy-rating concept based on a Massachusetts pilot project. The focus of the evaluation was on: (1) the compatibility of the Massachusetts rating with the RCS program, (2) who would use the rating and how, (3) qualitative estimates of benefits and costs, and (4) recommendations for further use and testing of the rating. In addition the evaluation of the rating concept also attempted to determine what if any effect the home energy rating has on the demand for energy audits, on the propensity of customers who received ratings to undertake recommended energy-efficiency home improvements, and on changes in mortgage-lending procedures for energy-efficient homes. The evaluation consisted of telephone and in-person discussions with the project developers, the various professional user groups, the recipients of the energy ratings, and control groups of audit customers that did not receive the energy rating. The evaluation was designed to determine the results of the pilot project, assess the project's effectiveness, and analyze the potential for transferring the rating procedure to other geographic locations.

  17. The impact of orbital sampling, monthly averaging and vertical resolution on climate chemistry model evaluation with satellite observations

    Directory of Open Access Journals (Sweden)

    A. M. Aghedo

    2011-07-01

    Full Text Available Ensemble climate model simulations used for the Intergovernmental Panel on Climate Change (IPCC assessments have become important tools for exploring the response of the Earth System to changes in anthropogenic and natural forcings. The systematic evaluation of these models through global satellite observations is a critical step in assessing the uncertainty of climate change projections. This paper presents the technical steps required for using nadir sun-synchronous infrared satellite observations for multi-model evaluation and the uncertainties associated with each step. This is motivated by need to use satellite observations to evaluate climate models. We quantified the implications of the effect of satellite orbit and spatial coverage, the effect of variations in vertical sensitivity as quantified by the observation operator and the impact of averaging the operators for use with monthly-mean model output. We calculated these biases in ozone, carbon monoxide, atmospheric temperature and water vapour by using the output from two global chemistry climate models (ECHAM5-MOZ and GISS-PUCCINI and the observations from the Tropospheric Emission Spectrometer (TES instrument on board the NASA-Aura satellite from January 2005 to December 2008.

    The results show that sampling and monthly averaging of the observation operators produce zonal-mean biases of less than ±3 % for ozone and carbon monoxide throughout the entire troposphere in both models. Water vapour sampling zonal-mean biases were also within the insignificant range of ±3 % (that is ±0.14 g kg−1 in both models. Sampling led to a temperature zonal-mean bias of ±0.3 K over the tropical and mid-latitudes in both models, and up to −1.4 K over the boundary layer in the higher latitudes. Using the monthly average of temperature and water vapour operators lead to large biases over the boundary layer in the southern-hemispheric higher latitudes and in the upper

  18. The impact of orbital sampling, monthly averaging and vertical resolution on climate chemistry model evaluation with satellite observations

    Directory of Open Access Journals (Sweden)

    A. M. Aghedo

    2011-03-01

    Full Text Available Ensemble climate model simulations used for the Intergovernmental Panel on Climate Change (IPCC assessments have become important tools for exploring the response of the Earth System to changes in anthropogenic and natural forcings. The systematic evaluation of these models through global satellite observations is a critical step in assessing the uncertainty of climate change projections. This paper presents the technical steps required for using nadir sun-synchronous infrared satellite observations for multi-model evaluation and the uncertainties associated with each step. This is motivated by need to use satellite observations to evaluate climate models. We quantified the implications of the effect of satellite orbit and spatial coverage, the effect of variations in vertical sensitivity as quantified by the observation operator and the impact of averaging the operators for use with monthly-mean model output. We calculated these biases in ozone, carbon monoxide, atmospheric temperature and water vapour by using the output from two global chemistry climate models (ECHAM5-MOZ and GISS-PUCCINI and the observations from the Tropospheric Emission Spectrometer (TES satellite from January 2005 to December 2008.

    The results show that sampling and monthly averaging of the observation operators produce biases of less than ±3% for ozone and carbon monoxide throughout the entire troposphere in both models. Water vapour sampling biases were also within the insignificant range of ±3% (that is ±0.14 g kg−1 in both models. Sampling led to a temperature bias of ±0.3 K over the tropical and mid-latitudes in both models, and up to −1.4 K over the boundary layer in the higher latitudes. Using the monthly average of temperature and water vapour operators lead to large biases over the boundary layer in the southern-hemispheric higher latitudes and in the upper troposphere, respectively. Up to 8% bias was calculated in the upper

  19. Framework Concept for Satellite Operations

    Science.gov (United States)

    2006-08-01

    provided in the following sections). The most outstanding features of the focusSuite GUI are: • Efficiency end ergonomy : Current Flight Dynamics GUIs...only brings substantial improvements in terms of efficiency and ergonomy but also provides additional functionality, including: • Detailed Events

  20. Small Satellite Formations for Distributed Surveillance: System Design and Optimal Control Considerations (Formations de petits satellites pour une surveillance distribuee: Considerations relatives la conception de systeme et a l’optimisation de commandes)

    Science.gov (United States)

    2009-04-01

    will be placed in orbit in order to provide higher temporal resolution in observation data and to achieve higher availability. Especially in emergency...l’observation terrestre , le potentiel d’innovation représenté par l’emploi d’un réseau distribué de satellites est devenu évident dès la réalisation...à ce jour, d’un tandem de deux satellites. A partir de 2008, des constellations de satellites seront placées en orbite pour obtenir une meilleure

  1. Characterization of solar thermal concepts for electricity generation: Volume 1, Analyses and evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Williams, T.A.; Dirks, J.A.; Brown, D.R.; Drost, M.K.; Antoniac, Z.A.; Ross, B.A.

    1987-03-01

    This study is aimed at providing a relative comparison of the thermodynamic and economic performance in electric applications of several concepts that have been studied and developed in the DOE solar thermal program. Since the completion of earlier systems comparison studies in the late 1970's, there have been a number of years of progress in solar thermal technology. This progress has included development of new solar components, improvements in component and system design detail, construction of working systems, and collection of operating data on the systems. This study provides an updating of the expected performance and cost of the major components and the overall system energy cost for the concepts evaluated. The projections in this study are for the late 1990's time frame, based on the capabilities of the technologies that could be expected to be achieved with further technology development.

  2. Application of Nonlinear Systems Inverses to Automatic Flight Control Design: System Concepts and Flight Evaluations

    Science.gov (United States)

    Meyer, G.; Cicolani, L.

    1981-01-01

    A practical method for the design of automatic flight control systems for aircraft with complex characteristics and operational requirements, such as the powered lift STOL and V/STOL configurations, is presented. The method is effective for a large class of dynamic systems requiring multi-axis control which have highly coupled nonlinearities, redundant controls, and complex multidimensional operational envelopes. It exploits the concept of inverse dynamic systems, and an algorithm for the construction of inverse is given. A hierarchic structure for the total control logic with inverses is presented. The method is illustrated with an application to the Augmentor Wing Jet STOL Research Aircraft equipped with a digital flight control system. Results of flight evaluation of the control concept on this aircraft are presented.

  3. The Affect Heuristic and the Concept of "Evaluability": Experiments in the Brazilian Context

    Directory of Open Access Journals (Sweden)

    Marcos Gonçalves Avila

    2013-06-01

    Full Text Available Recent literature has discussed the concept of affect as a judgment heuristic: affective responses tend to occur rapidly and automatically and serve as mental shortcuts in decision processes (Slovic et al, 2002. Bateman et al. (2007, examined the role of affect in determining judgments and decisions and described experiments demonstrating that the introduction of a small loss as a component of a game increases its attractiveness. In this study we replicate these experiments with similar results and discuss the concept of evaluability (Hsee, 1996, 1998, Slovic et al., 2002 and Bateman et al., 2007 to explain these findings. In general, the results demonstrate the importance of contextual factors in determining affective impressions and provide support to the related proposition regarding the importance of the heuristic of affect in judgment and decision-making. DOI: 10.5585/remark.v12i2.2487

  4. An evaluation and regional error modeling methodology for near-real-time satellite rainfall data over Australia

    Science.gov (United States)

    Pipunic, Robert C.; Ryu, Dongryeol; Costelloe, Justin F.; Su, Chun-Hsu

    2015-10-01

    In providing uniform spatial coverage, satellite-based rainfall estimates can potentially benefit hydrological modeling, particularly for flood prediction. Maximizing the value of information from such data requires knowledge of its error. The most recent Tropical Rainfall Measuring Mission (TRMM) 3B42RT (TRMM-RT) satellite product version 7 (v7) was used for examining evaluation procedures against in situ gauge data across mainland Australia at a daily time step, over a 9 year period. This provides insights into estimating uncertainty and informing quantitative error model development, with methodologies relevant to the recently operational Global Precipitation Measurement mission that builds upon the TRMM legacy. Important error characteristics highlighted for daily aggregated TRMM-RT v7 include increasing (negative) bias and error variance with increasing daily gauge totals and more reliability at detecting larger gauge totals with a probability of detection of data have increasing (positive) bias and error variance with increasing TRMM-RT estimates. Difference errors binned within 10 mm/d increments of TRMM-RT v7 estimates highlighted negatively skewed error distributions for all bins, suitably approximated by the generalized extreme value distribution. An error model based on this distribution enables bias correction and definition of quantitative uncertainty bounds, which are expected to be valuable for hydrological modeling and/or merging with other rainfall products. These error characteristics are also an important benchmark for assessing if/how future satellite rainfall products have improved.

  5. Performance evaluation of land mobile satellite system under fading and interference using multiple TCM by Monte-Carlo simulation

    Science.gov (United States)

    Kwa, S. C.; Vanderaar, Mark J.; Kim, Junghwan; Stevens, Grady H.

    1991-01-01

    The performance of the land mobile satellite system (LMSS) was evaluated by using two trellis coded modulation (TCM) schemes under multipath fading and interference. The results were also compared with uncoded QPSK. The trellis coding formats included a trellis code designed for optimum performance on the fading channel that typifies satellite to mobile communications, as well as one designed for optimum performance in the additive white Gaussian noise (AWGN) channel. The results show that, in Rayleigh fading, the TCM code designed for optimum performance in such an environment performs 4 dB better than the TCM code designed for optimum performance in AWGN, and 10 dB better than the uncoded format, at a bit error rate (BER) of 10 exp -4. Additional results on the performance degradation due to the nonlinearities in the satellite transponder and the adjacent and cochannel interference show that the TCM system is more sensitive than the uncoded system to the phase distortion caused by these impairments.

  6. Validation Of The Airspace Concept Evaluation System Using Real World Data

    Science.gov (United States)

    Zelinski, Shannon

    2005-01-01

    This paper discusses the process of performing a validation of the Airspace Concept Evaluation System (ACES) using real world historical flight operational data. ACES inputs are generated from select real world data and processed to create a realistic reproduction of a single day of operations within the National Airspace System (NAS). ACES outputs are then compared to real world operational metrics and delay statistics for the reproduced day. Preliminary results indicate that ACES produces delays and airport operational metrics similar to the real world with minor variations of delay by phase of flight. ACES is a nation-wide fast-time simulation tool developed at NASA Ames Research Center. ACES models and simulates the NAS using interacting agents representing center control, terminal flow management, airports, individual flights, and other NAS elements. These agents pass messages between one another similar to real world communications. This distributed agent based system is designed to emulate the highly unpredictable nature of the NAS, making it a suitable tool to evaluate current and envisioned airspace concepts. To ensure that ACES produces the most realistic results, the system must be validated. There is no way to validate future concepts scenarios using real world historical data, but current day scenario validations increase confidence in the validity of future scenario results. Each operational day has unique weather and traffic demand schedules. The more a simulation utilizes the unique characteristic of a specific day, the more realistic the results should be. ACES is able to simulate the full scale demand traffic necessary to perform a validation using real world data. Through direct comparison with the real world, models may continuee to be improved and unusual trends and biases may be filtered out of the system or used to normalize the results of future concept simulations.

  7. Existing and Required Modeling Capabilities for Evaluating ATM Systems and Concepts

    Science.gov (United States)

    Odoni, Amedeo R.; Bowman, Jeremy; Delahaye, Daniel; Deyst, John J.; Feron, Eric; Hansman, R. John; Khan, Kashif; Kuchar, James K.; Pujet, Nicolas; Simpson, Robert W.

    1997-01-01

    ATM systems throughout the world are entering a period of major transition and change. The combination of important technological developments and of the globalization of the air transportation industry has necessitated a reexamination of some of the fundamental premises of existing Air Traffic Management (ATM) concepts. New ATM concepts have to be examined, concepts that may place more emphasis on: strategic traffic management; planning and control; partial decentralization of decision-making; and added reliance on the aircraft to carry out strategic ATM plans, with ground controllers confined primarily to a monitoring and supervisory role. 'Free Flight' is a case in point. In order to study, evaluate and validate such new concepts, the ATM community will have to rely heavily on models and computer-based tools/utilities, covering a wide range of issues and metrics related to safety, capacity and efficiency. The state of the art in such modeling support is adequate in some respects, but clearly deficient in others. It is the objective of this study to assist in: (1) assessing the strengths and weaknesses of existing fast-time models and tools for the study of ATM systems and concepts and (2) identifying and prioritizing the requirements for the development of additional modeling capabilities in the near future. A three-stage process has been followed to this purpose: 1. Through the analysis of two case studies involving future ATM system scenarios, as well as through expert assessment, modeling capabilities and supporting tools needed for testing and validating future ATM systems and concepts were identified and described. 2. Existing fast-time ATM models and support tools were reviewed and assessed with regard to the degree to which they offer the capabilities identified under Step 1. 3 . The findings of 1 and 2 were combined to draw conclusions about (1) the best capabilities currently existing, (2) the types of concept testing and validation that can be carried

  8. Resurs-P" Satellite Hyperspectral Data: Preliminary Evaluation of Information Capacities

    Science.gov (United States)

    Zelentsov, Viacheslav; Sokolov, Boris; Grigorieva, Olga; Mochalov, Viktor; Potryasaev, Semen; Shumeiko, Viktor

    2016-08-01

    Satellite-based hyperspectral sensors provide spectroscopic information in relatively narrow contiguous spectral bands over a large area, and this property can be useful for a lot of practical tasks. "Resurs-P" hyperspectral equipment provides a new class of Earth observation data to improve Earth surface observability. The main features of this equipment are considered and the results of new hyperspectral data applications to solve problems vineyards and forest analysis and also depths measurements are given in the article.

  9. Evaluation of the Chinese Fine Spatial Resolution Hyperspectral Satellite TianGong-1 in Urban Land-Cover Classification

    Directory of Open Access Journals (Sweden)

    Xueke Li

    2016-05-01

    Full Text Available The successful launch of the Chinese high spatial resolution hyperspectral satellite TianGong-1 (TG-1 opens up new possibilities for applications of remotely-sensed satellite imagery. One of the main goals of the TG-1 mission is to provide observations of surface attributes at local and landscape spatial scales to map urban land cover accurately using the hyperspectral technique. This study attempted to evaluate the TG-1 datasets for urban feature analysis, using existing data over Beijing, China, by comparing the TG-1 (with a spatial resolution of 10 m to EO-1 Hyperion (with a spatial resolution of 30 m. The spectral feature of TG-1 was first analyzed and, thus, finding out optimal hyperspectral wavebands useful for the discrimination of urban areas. Based on this, the pixel-based maximum likelihood classifier (PMLC, pixel-based support vector machine (PSVM, hybrid maximum likelihood classifier (HMLC, and hybrid support vector machine (HSVM were implemented, as well as compared in the application of mapping urban land cover types. The hybrid classifier approach, which integrates the pixel-based classifier and the object-based segmentation approach, was demonstrated as an effective alternative to the conventional pixel-based classifiers for processing the satellite hyperspectral data, especially the fine spatial resolution data. For TG-1 imagery, the pixel-based urban classification was obtained with an average overall accuracy of 89.1%, whereas the hybrid urban classification was obtained with an average overall accuracy of 91.8%. For Hyperion imagery, the pixel-based urban classification was obtained with an average overall accuracy of 85.9%, whereas the hybrid urban classification was obtained with an average overall accuracy of 86.7%. Overall, it can be concluded that the fine spatial resolution satellite hyperspectral data TG-1 is promising in delineating complex urban scenes, especially when using an appropriate classifier, such as the

  10. Evaluating the strength of the land-atmosphere moisture feedback in Earth system models using satellite observations

    Science.gov (United States)

    Levine, Paul A.; Randerson, James T.; Swenson, Sean C.; Lawrence, David M.

    2016-12-01

    The relationship between terrestrial water storage (TWS) and atmospheric processes has important implications for predictability of climatic extremes and projection of future climate change. In places where moisture availability limits evapotranspiration (ET), variability in TWS has the potential to influence surface energy fluxes and atmospheric conditions. Where atmospheric conditions, in turn, influence moisture availability, a full feedback loop exists. Here we developed a novel approach for measuring the strength of both components of this feedback loop, i.e., the forcing of the atmosphere by variability in TWS and the response of TWS to atmospheric variability, using satellite observations of TWS, precipitation, solar radiation, and vapor pressure deficit during 2002-2014. Our approach defines metrics to quantify the relationship between TWS anomalies and climate globally on a seasonal to interannual timescale. Metrics derived from the satellite data were used to evaluate the strength of the feedback loop in 38 members of the Community Earth System Model (CESM) Large Ensemble (LENS) and in six models that contributed simulations to phase 5 of the Coupled Model Intercomparison Project (CMIP5). We found that both forcing and response limbs of the feedback loop in LENS were stronger than in the satellite observations in tropical and temperate regions. Feedbacks in the selected CMIP5 models were not as strong as those found in LENS, but were still generally stronger than those estimated from the satellite measurements. Consistent with previous studies conducted across different spatial and temporal scales, our analysis suggests that models may overestimate the strength of the feedbacks between the land surface and the atmosphere. We describe several possible mechanisms that may contribute to this bias, and discuss pathways through which models may overestimate ET or overestimate the sensitivity of ET to TWS.

  11. Evaluating Biosphere Model Estimates of the Start of the Vegetation Active Season in Boreal Forests by Satellite Observations

    Directory of Open Access Journals (Sweden)

    Kristin Böttcher

    2016-07-01

    Full Text Available The objective of this study was to assess the performance of the simulated start of the photosynthetically active season by a large-scale biosphere model in boreal forests in Finland with remote sensing observations. The start of season for two forest types, evergreen needle- and deciduous broad-leaf, was obtained for the period 2003–2011 from regional JSBACH (Jena Scheme for Biosphere–Atmosphere Hamburg runs, driven with climate variables from a regional climate model. The satellite-derived start of season was determined from daily Moderate Resolution Imaging Spectrometer (MODIS time series of Fractional Snow Cover and the Normalized Difference Water Index by applying methods that were targeted to the two forest types. The accuracy of the satellite-derived start of season in deciduous forest was assessed with bud break observations of birch and a root mean square error of seven days was obtained. The evaluation of JSBACH modelled start of season dates with satellite observations revealed high spatial correspondence. The bias was less than five days for both forest types but showed regional differences that need further consideration. The agreement with satellite observations was slightly better for the evergreen than for the deciduous forest. Nonetheless, comparison with gross primary production (GPP determined from CO2 flux measurements at two eddy covariance sites in evergreen forest revealed that the JSBACH-simulated GPP was higher in early spring and led to too-early simulated start of season dates. Photosynthetic activity recovers differently in evergreen and deciduous forests. While for the deciduous forest calibration of phenology alone could improve the performance of JSBACH, for the evergreen forest, changes such as seasonality of temperature response, would need to be introduced to the photosynthetic capacity to improve the temporal development of gross primary production.

  12. Evaluation of cloud base height measurements from ceilometer CL31 and MODIS satellite over Ahmedabad, India

    Directory of Open Access Journals (Sweden)

    S. Sharma

    2015-11-01

    Full Text Available Clouds play a tangible role in the Earth's atmosphere and in particular, the cloud base height (CBH which is linked to cloud type is one of the important characteristic to describe the influence of clouds on the environment. In present study, CBH observations from ceilometer CL31 have been extensively studied during May 2013 to January 2015 over Ahmedabad (23.03° N, 72.54° E, India. A detail comparison has been performed with the use of ground-based CBH measurements from ceilometer CL31 and CBH retrieved from MODIS (Moderate Resolution Imaging Spectroradiometer onboard Aqua and Terra satellite. Some interesting features of cloud dynamics viz. strong downdraft and updraft have been observed over Ahmedabad which revealed different cloud characteristics during monsoon and post-monsoon periods. CBH shows seasonal variation during Indian summer monsoon and post-monsoon period. Results indicate that ceilometer is one of the excellent instruments to precisely detect low and mid-level clouds and MODIS satellite provides accurate retrieval of high-level clouds over this region. The CBH algorithm used for MODIS satellite is also able to capture the low-level clouds.

  13. Computer-aided evaluation of the railway track geometry on the basis of satellite measurements

    Science.gov (United States)

    Specht, Cezary; Koc, Władysław; Chrostowski, Piotr

    2016-05-01

    In recent years, all over the world there has been a period of intensive development of GNSS (Global Navigation Satellite Systems) measurement techniques and their extension for the purpose of their applications in the field of surveying and navigation. Moreover, in many countries a rising trend in the development of rail transportation systems has been noticed. In this paper, a method of railway track geometry assessment based on mobile satellite measurements is presented. The paper shows the implementation effects of satellite surveying railway geometry. The investigation process described in the paper is divided on two phases. The first phase is the GNSS mobile surveying and the analysis obtained data. The second phase is the analysis of the track geometry using the flat coordinates from the surveying. The visualization of the measured route, separation and quality assessment of the uniform geometric elements (straight sections, arcs), identification of the track polygon (main directions and intersection angles) are discussed and illustrated by the calculation example within the article.

  14. Evaluation of a Hydrogen Fuel Cell Powered Blended-Wing-Body Aircraft Concept for Reduced Noise and Emissions

    Science.gov (United States)

    Guynn, Mark D.; Freh, Joshua E.; Olson, Erik D.

    2004-01-01

    This report describes the analytical modeling and evaluation of an unconventional commercial transport aircraft concept designed to address aircraft noise and emission issues. A blended-wing-body configuration with advanced technology hydrogen fuel cell electric propulsion is considered. Predicted noise and emission characteristics are compared to a current technology conventional configuration designed for the same mission. The significant technology issues which have to be addressed to make this concept a viable alternative to current aircraft designs are discussed. This concept is one of the "Quiet Green Transport" aircraft concepts studied as part of NASA's Revolutionary Aerospace Systems Concepts (RASC) Program. The RASC Program was initiated to develop revolutionary concepts that address strategic objectives of the NASA Enterprises, such as reducing aircraft noise and emissions, and to identify advanced technology requirements for the concepts.

  15. Seasat-satellite investigation of the structure of western Nebraska and its application to the evaluation of geothermal resources

    Energy Technology Data Exchange (ETDEWEB)

    Stix, J.

    1982-03-01

    Seasat synthetic aperture radar (SAR) satellite imagery was used to interpret the structural framework and, indirectly, the geothermal potential of an area in western Nebraska. Lineaments were mapped from the imagery and then compared to known structure. It was found that Seasat does record surface manifestations of subtle basement structures, particularly faults and joints. Furthermore, two areas with hot dry rock geothermal potential were delineated using Seasat and other data. It is stressed that more subsurface geology and geophysical data are needed before a final evaluation of the geothermal potential can be made. Seasat imagery is a useful reconnaissance exploration tool in the interpretation of regional structure within areas of little topographic relief.

  16. Dynamic characteristics and performance evaluation for the part strut failure of the vibration isolation platform on satellites

    Science.gov (United States)

    Zhang, Yao; Sheng, Chao; Guo, Zixi; Wang, Youyi; Li, Wenbo

    2017-04-01

    The dynamic characteristics and performance evaluation for the part strut failure of the vibration isolation platform are presented in this paper. The first step provides and mathematically describes two types of strut failure: fractured and stuck. Secondly, the dynamic model of the vibration isolation platform, which considers the part strut failure, is established using the Newton-Euler method and a constraint equation to evaluate its dynamic characteristics and performance. Then, with reasonable assumptions, the dynamic model of the satellite, which has a vibration isolation platform and vibration sources (such as control moment gyros) of three working situations (without and with two types of strut failure), is simplified to analyse the frequency domain characteristic and coupling characteristic with the attitude control system. Finally, a numerical simulation is used to study the effect of the vibration isolation platform with part strut failure on the attitude control and stabilization, and the attitude control performance is evaluated.

  17. Evaluation of power control concepts using the PMAD systems test bed. [Power Management and Distribution

    Science.gov (United States)

    Beach, R. F.; Kimnach, G. L.; Jett, T. A.; Trash, L. M.

    1989-01-01

    The Lewis Research Center's Power Management and Distribution (PMAD) System testbed and its use in the evaluation of control concepts applicable to the NASA Space Station Freedom electric power system (EPS) are described. The facility was constructed to allow testing of control hardware and software in an environment functionally similar to the space station electric power system. Control hardware and software have been developed to allow operation of the testbed power system in a manner similar to a supervisory control and data acquisition (SCADA) system employed by utility power systems for control. The system hardware and software are described.

  18. Evaluation of Synthetic Vision Display Concepts for Improved Awareness in Unusual Attitude Recovery Scenarios

    Science.gov (United States)

    Nicholas, Stephanie

    2016-01-01

    A recent study conducted by the Commercial Aviation Safety Team (CAST) determined 40 percent of all fixed-wing fatal accidents, between 2001 and 2011, were caused by Loss-of-Control (LOC) in flight (National Transportation Safety Board, 2015). Based on their findings, CAST recommended manufacturers develop and implement virtual day-visual meteorological conditions (VMC) display systems, such as synthetic vision or equivalent systems (CAST, 2016). In a 2015 simulation study conducted at NASA Langley Research Center (LaRC), researchers gathered to test and evaluate virtual day-VMC displays under realistic flight operation scenarios capable of inducing reduced attention states in pilots. Each display concept was evaluated to determine its efficacy to improve attitude awareness. During the experiment, Evaluation Pilots (EPs) were shown the following three display concepts on the Primary Flight Display (PFD): Baseline, Synthetic Vision (SV) with color gradient, and SV with texture. The baseline configuration was a standard, conventional 'blue over brown' display. Experiment scenarios were simulated over water to evaluate Unusual Attitude (UA) recovery over 'featureless terrain' environments. Thus, the SV with color gradient configuration presented a 'blue over blue' display with a linear blue color progression, to differentiate attitude changes between sky and ocean. The SV with texture configuration presented a 'blue over blue' display with a black checkerboard texture atop a synthetic ocean. These displays were paired with a Background Attitude Indicator (BAI) concept. The BAI was presented across all four Head-Down Displays (HDDs), displaying a wide field-of-view blue-over-blue attitude indicator. The BAI aligned with the PFD and showed through the background of the navigation displays with opaque transparency. Each EP participated in a two-part experiment series with a total seventy-five trial runs: Part I included a set of twenty-five Unusual Attitude Recovery (UAR

  19. Multinational Design Evaluation Program; Programme multinational d'evaluation des conceptions (MDEP)

    Energy Technology Data Exchange (ETDEWEB)

    Holahan, G. [Bureau des Nouveaux Reacteurs, Commission deRegulation Nucleaire Americaine, Comite de Direction Technique du Programme MDEP (United States); Williams, S. [Bureau des Nouveaux Reacteurs, NRC, Autorite de Surete Americaine (United States)

    2010-02-15

    The Multinational Design Evaluation Programme (MDEP) is one of the most ambitious initiatives taken at multinational level to develop approaches to combine resources and knowledge of the national regulatory authorities who will be undertaking the regulatory review of new reactor power plant designs. Launched on the basis of the existing cooperation between United States (Nuclear Regulatory Commission - NRC) and France (Nuclear Safety Authority - ASN), this initiative, to date, brings together Canada, China, Finland, France, Japan, Russia, South Africa, South Korea, the United Kingdom and the United States. Under MDEP, nuclear regulators are aiming to enhance safety worldwide through increased co-operation. The enhanced co-operation among regulators will improve the efficiency and the effectiveness of the design review process, aiming at increased convergence of regulatory practices. (authors)

  20. Evaluation of Seafood Product Concepts by Young Adults and Families with Young Children from Denmark, Norway, and Iceland

    NARCIS (Netherlands)

    Altintzoglou, T.; Sveinsdottir, K.; Einarsdottir, G.; Schelvis, R.; Luten, J.B.

    2012-01-01

    This article describes the results of a study that tested the responses to 14 seafood concepts among young adults and families with young children in Denmark, Norway, and Iceland. This study was aimed at gaining insight into the evaluation of new seafood product concepts by individuals with low seaf

  1. Evaluation of methods to derive green-up dates based on daily NDVI satellite observations

    Science.gov (United States)

    Doktor, Daniel

    2010-05-01

    Bridging the gap between satellite derived green-up dates and in situ phenological observations has been the purpose of many studies over the last decades. Despite substantial advancements in satellite technology and data quality checks there is as yet no universally accepted method for extracting phenological metrics based on satellite derived vegetation indices. Dependent on the respective method derived green-up dates can vary up to serveral weeks using identical data sets. Consequently, it is difficult to compare various studies and to accurately determine an increased vegetation length due to changing temperature patterns as observed by ground phenological networks. Here, I compared how the characteristic NDVI increase over temperate deciduous forests in Germany in spring relates to respective budburst events observed on the ground. MODIS Terra daily surface reflectances with a 250 m resolution (2000-2008) were gathered to compute daily NDVI values. As ground truth, observations of the extensive phenological network of the German Weather Service were used. About 1500 observations per year and species (Beech, Oak and Birch) were available evenly distributed all over Germany. Two filtering methods were tested to reduce the noisy raw data. The first method only keeps NDVI values which are classified as ‚ideal global quality' and applies on those a temporal moving window where values are removed which differ more than 20% of the mean. The second method uses an adaptation of the BISE (Best Index Slope Extraction) algorithm. Subsequently, three functions were fitted to the selected observations: a simple linear interpolation, a sigmoidal function and a double logistic sigmoidal function allowing to approximate two temporally separated green-up signals. The green-up date was then determined at halfway between minimum and maximum (linear interpolation) or at the inflexion point of the sigmoidal curve. A number of global threshold values (NDVI 0.4,0.5,0.6) and

  2. Development, evaluation, and use of a genetic literacy concept inventory for undergraduates

    Science.gov (United States)

    Bowling, Bethany Vice

    There is continued emphasis on increasing and improving genetics education for grades K-12, medical professionals, and the general public. An additional critical audience is the undergraduate student in introductory biology and genetics courses. There has been little effort to assess these students' understanding of genetics concepts and their level of genetic literacy (i.e. genetics knowledge as it relates to and impacts their lives). We have developed, evaluated, and used a new survey instrument to assess the genetic literacy of undergraduate students taking introductory biology or genetics courses. The Genetic Literacy Concept Inventory (GLCI) is a 31-item multiple choice test that addresses 17 concepts identified as central to genetic literacy by a team of ASHG professional geneticists. The items were selected and modified based upon reviews by 25 genetic professionals and educators. The inventory underwent additional review in student focus groups and pilot testing. Analysis was carried out on content validity, discriminate validity, internal consistency, and stability of the inventory, with results indicating it is reasonably valid and reliable. The GLCI has been utilized pre-course and post-course in six introductory non-major biology and genetics courses, with over 350 students taking the inventory. Current data from students in introductory biology courses show a pre-course average of 41% correct. Post-course scores increased only modestly to an average of 48% in these courses which emphasized genetics to varying degrees. Even in an introductory genetics course the pre-course average of 54% increased to only 59%. These results are consistent with similar studies in physics and chemistry where concept inventories have been implemented in courses using more traditional teaching methods. This study directly enhances genetics education research by providing a valid and reliable instrument for assessing genetic literacy in undergraduate students. It also begins

  3. Evaluation end-of-life power generation of a satellite solar array

    Energy Technology Data Exchange (ETDEWEB)

    Taherbaneh, Mohsen, E-mail: taherbaneh@aut.ac.i [Iranian Research Organization for Science and Technology, Tehran (Iran, Islamic Republic of); Amirkabir University of Technology, Tehran 15916-34311 (Iran, Islamic Republic of); Ghafooifard, H.; Rezaie, A.H. [Amirkabir University of Technology, Tehran 15916-34311 (Iran, Islamic Republic of); Rahimi, K. [Iranian Research Organization for Science and Technology, Tehran (Iran, Islamic Republic of)

    2011-07-15

    Research highlights: {yields} We present detailed design description and necessary considerations for solar panels utilized in a specific space mission. {yields} All sources of losses and degradation of the solar panels are fully taken into account. {yields} We introduce a comprehensive novel approach to investigate the electrical behavior of the solar panels. {yields} We use a simple model to calculate the operating temperature range of the solar panels. {yields} We also calculate Mission End-of-Life electrone fluence using SPENVIS. -- Abstract: Knowing the power generated by of solar arrays in a space missions shall satisfy mission requirements; prediction of the power generated by a solar array used in a space mission is very important and necessary. In this research, a detailed design description and necessary considerations for solar panels utilized in a specific space mission is presented. All sources of losses and degradation of solar panels are fully taken into account. This research emphasizes on investigation, analysis and verification of a manufactured solar assembly for a satellite before launch. Solar panels' generated power should be estimated at the end of the mission. For this purpose, radiation values and temperature operating range are specified for the mission. Panels' temperature operating rate is determined through considering a simple model and different spins for the satellite. Mission end-of-life 1 MeV equivalent dose is calculated by SPENVIS suite software. Finally, a comprehensive novel approach is introduced to investigate the electrical behavior of the solar panels. This approach can be implemented in MATLAB environment to obtain output power characteristics of the solar panels for each specific mission. The results are in full accordance with the mission requirements either in beginning-of-life or end-of-life. Therefore, the power prediction of the designed solar array for the mentioned satellite completely satisfies its

  4. Evaluating complex health interventions: a critical analysis of the 'outcomes' concept

    Directory of Open Access Journals (Sweden)

    Launsø Laila

    2009-06-01

    Full Text Available Abstract Background The extent to which a health care intervention causes or facilitates health-related change is a key question in research. The need to quantify such change has led to the development of an increasing number of change indicators, to measure what have come to be known as 'outcomes'. In the context of medical research into the efficacy or effectiveness of an intervention the term 'outcomes' has often been interpreted to mean single endpoints with a linear cause and effect link to an external intervention. Discussion In this paper we present a critical analysis of the nature and interpretation of the 'outcomes' concept and of the assumptions that underpin it. Drawing on our own work and that of others, we analyse the problems that arise when the concept is applied to complex interventions and discuss the use of other models, such as programme theory, as a basis for alternative conceptualisations for indicators of change. Our analysis demonstrates that the interpretation of 'outcomes' that may be appropriate for clinical trials of pharmaceutical products, is problematic when used in evaluations of complex interventions in areas such as complementary medicine, palliative care, rehabilitation, and health promotion. The 'outcomes' concept may impose inappropriate patterns of thought and meaning. We present alternative models, such as those based on programme theory, which conceptualise health-related change as resulting from the interaction between intervention, process and context over time. In this framework both the intervention and the patient are defined as causal factors, because the result of the treatment is dependent on the resources of the patient – such as the body's ability to heal itself – and the impact of the patient's situation. Summary Evaluations based on a model such as programme theory will encompass a wide range of health-related changes that include aspects of process, such as new meanings and understanding

  5. "Workhood"-a useful concept for the analysis of health workers' resources? an evaluation from Tanzania

    Directory of Open Access Journals (Sweden)

    Gross Karin

    2012-03-01

    Full Text Available Abstract Background International debates on improving health system performance and quality of care are strongly coined by systems thinking. There is a surprising lack of attention to the human (worker elements. Although the central role of health workers within the health system has increasingly been acknowledged, there are hardly studies that analyze performance and quality of care from an individual perspective. Drawing on livelihood studies in health and sociological theory of capitals, this study develops and evaluates the new concept of workhood. As an analytical device the concept aims at understanding health workers' capacities to access resources (human, financial, physical, social, cultural and symbolic capital and transfer them to the community from an individual perspective. Methods Case studies were conducted in four Reproductive-and-Child-Health (RCH clinics in the Kilombero Valley, south-eastern Tanzania, using different qualitative methods such as participant observation, informal discussions and in-depth interviews to explore the relevance of the different types of workhood resources for effective health service delivery. Health workers' ability to access these resources were investigated and factors facilitating or constraining access identified. Results The study showed that lack of physical, human, cultural and financial capital constrained health workers' capacity to act. In particular, weak health infrastructure and health system failures led to the lack of sufficient drug and supply stocks and chronic staff shortages at the health facilities. However, health workers' capacity to mobilize social, cultural and symbolic capital played a significant role in their ability to overcome work related problems. Professional and non-professional social relationships were activated in order to access drug stocks and other supplies, transport and knowledge. Conclusions By evaluating the workhood concept this study highlights the

  6. "Workhood"-a useful concept for the analysis of health workers' resources? An evaluation from Tanzania.

    Science.gov (United States)

    Gross, Karin; Pfeiffer, Constanze; Obrist, Brigit

    2012-03-08

    International debates on improving health system performance and quality of care are strongly coined by systems thinking. There is a surprising lack of attention to the human (worker) elements. Although the central role of health workers within the health system has increasingly been acknowledged, there are hardly studies that analyze performance and quality of care from an individual perspective. Drawing on livelihood studies in health and sociological theory of capitals, this study develops and evaluates the new concept of workhood. As an analytical device the concept aims at understanding health workers' capacities to access resources (human, financial, physical, social, cultural and symbolic capital) and transfer them to the community from an individual perspective. Case studies were conducted in four Reproductive-and-Child-Health (RCH) clinics in the Kilombero Valley, south-eastern Tanzania, using different qualitative methods such as participant observation, informal discussions and in-depth interviews to explore the relevance of the different types of workhood resources for effective health service delivery. Health workers' ability to access these resources were investigated and factors facilitating or constraining access identified. The study showed that lack of physical, human, cultural and financial capital constrained health workers' capacity to act. In particular, weak health infrastructure and health system failures led to the lack of sufficient drug and supply stocks and chronic staff shortages at the health facilities. However, health workers' capacity to mobilize social, cultural and symbolic capital played a significant role in their ability to overcome work related problems. Professional and non-professional social relationships were activated in order to access drug stocks and other supplies, transport and knowledge. By evaluating the workhood concept this study highlights the importance of understanding health worker performance by looking at

  7. Combining psychophysical measures of discomfort and electromyography for the evaluation of a new automotive seating concept.

    Science.gov (United States)

    Kolich, Mike; Taboun, Salem M

    2002-01-01

    The purpose of this study was to determine if the advantages and disadvantages of a new automotive seating concept, known as the micro-adjuster control system, could be reliably evaluated using both a physiological assessment technique (i.e., electromyography [EMG]) and a subjective questionnaire. The results indicate that psychophysical measures of discomfort and the root mean squared (RMS) activity of the EMG are statistically related, r (8) = -.788, p =.020. More specifically, subjective perceptions of comfort were found to improve with decreasing levels of muscle activity. This implies that seat comfort can be evaluated on the basis of physiological as well as subjective responses to prolonged driving. This finding should drastically improve automobile seat design efforts.

  8. Evaluating Frontal Precipitation with a Spectral Microphysics Mesoscale Model and a Satellite Simulator as Compared to Radar and Radiometer Observations

    Science.gov (United States)

    Han, M.; Braun, S. A.; Matsui, T.; Iguchi, T.; Williams, C. R.

    2013-12-01

    The Advanced Microwave Scanning Radiometer for EOS (AMSR-E) onboard NASA Aqua satellite and a ground-based precipitation profiling radar sampled a frontal precipitation event in the US west coast on 30 to 31 December 2005. Simulations with bulk microphysics schemes in the Weather Research and Forecast (WRF) model have been evaluated with those remote sensing data. In the current study, we continue similar work to evaluate a spectral bin microphysics (SBM) scheme, HUCM, in the WRF model. The Goddard-Satellite Data Simulation Unit (G-SDSU) is used to simulate quantities observed by the radar and radiometer. With advanced representation of cloud and precipitation microphysics processes, the HUCM scheme predicts distributions of 7 hydrometeor species as storms evolve. In this study, the simulation with HUCM well captured the structure of the precipitation and its microphysics characteristics. In addition, it improved total precipitation ice mass simulation and corrected, to a certain extent, the large low bias of ice scattering signature in the bulk scheme simulations. However, the radar reflectivity simulations with the HUCM scheme were not improved as compared to the bulk schemes. We conducted investigations to understand how microphysical processes and properties, such as snow break up parameter and particle fall velocities would influence precipitation size distribution and spectrum of water paths, and further modify radar and/or radiometer simulations. Influence by ice nuclei is going to be examined as well.

  9. Preliminary survey and evaluation of nonaquifer thermal energy storage concepts for seasonal storage

    Energy Technology Data Exchange (ETDEWEB)

    Blahnik, D.E.

    1980-11-01

    Thermal energy storage enables the capture and retention of heat energy (or cold) during one time period for use during another. Seasonal thermal energy storage (STES) involves a period of months between the input and recovery of energy. The purpose of this study was to make a preliminary investigation and evaluation of potential nonaquifer STES systems. Current literature was surveyed to determine the state of the art of thermal energy storage (TES) systems such as hot water pond storage, hot rock storage, cool ice storage, and other more sophisticated concepts which might have potential for future STES programs. The main energy sources for TES principally waste heat, and the main uses of the stored thermal energy, i.e., heating, cooling, and steam generation are described. This report reviews the development of sensible, latent, and thermochemical TES technologies, presents a preliminary evaluation of the TES methods most applicable to seasonal storage uses, outlines preliminary conclusions drawn from the review of current TES literature, and recommends further research based on these conclusions. A bibliography of the nonaquifer STES literature review, and examples of 53 different TES concepts drawn from the literature are provided. (LCL)

  10. Operational Concept Evaluation of Solid Oxide Fuel Cells for Space Vehicle Applications

    Science.gov (United States)

    Poast, Kenneth I.

    2011-01-01

    With the end of the Space Shuttle Program, NASA is evaluating many different technologies to support future missions. Green propellants, like liquid methane and liquid oxygen, have potential advantages for some applications. A Lander propelled with LOX/methane engines is one such application. When the total vehicle design and infrastructure are considered, the advantages of the integration of propulsion, heat rejection, life support and power generation become attractive for further evaluation. Scavenged residual propellants from the propulsion tanks could be used to generate needed electric power, heat and water with a Solid Oxide Fuel Cell(SOFC). In-Situ Resource Utilization(ISRU) technologies may also generate quantities of green propellants to refill these tanks and/or supply these fuel cells. Technology demonstration projects such as the Morpheus Lander are currently underway to evaluate the practicality of such designs and operational concepts. Tethered tests are currently in progress on this vertical test bed to evaluate the propulsion and avionics systems. Evaluation of the SOFC seeks to determine the feasibility of using these green propellants to supply power and identify the limits to the integration of this technology into a space vehicle prototype.

  11. Evaluation of a gallium arsenide solar panel on the LIPS II satellite

    Energy Technology Data Exchange (ETDEWEB)

    Trumble, T.M.; Betz, F.

    1984-05-01

    On 10 February 1983 the Living Plume Shield (LIPS II) satellite was launched by the Naval Research Laboratory with three double sided solar panels providing electrical power. One side of one panel contains 300 2cm X 2cm gallium arsenide (GaAs) solar cells while each of the other five sides contain 104 2.1cm X 6.2cm silicon (Si) solar cells. The U.S. Air Force developed GaAs cells were provided to the Navy in a cooperative program to build, test, qualify and fly a GaAs solar panel. Nineteen months after the beginning of the cooperative program the vehicle was launched. There are considerable statistical variances in the data and data cannot be acquired continuously owing to the requirement to be over a tracking station while the GaAs panel is facing the sun. The first 30 days of operation were unmeasured due to satellite orientation problems. The first measurements indicated a 7.3% power loss in panel performance compared to ground preflight measurements. This loss is still unexplained. This paper provides a summary of the LIPS II program and the data analysis on the GaAs solar panel performance for the first year in orbit.

  12. Cloud mask via cumulative discriminant analysis applied to satellite infrared observations: scientific basis and initial evaluation

    Directory of Open Access Journals (Sweden)

    U. Amato

    2014-06-01

    Full Text Available We introduce a classification method (Cumulative Discriminant Analysis of the Discriminant Analysis type to discriminate between cloudy and clear sky satellite observations in the thermal infrared. The tool is intended for the high spectral resolution infrared sounder (IRS planned for the geostationary METEOSAT (Meteorological Satellite Third Generation platform and uses IASI (Infrared Atmospheric Sounding Interferometer data as a proxy. The Cumulative Discriminant Analysis does not introduce biases intrinsic with the approximation of the probability density functions and is flexible enough to adapt to different strategies to optimize the cloud mask. The methodology is based on nine statistics computed from IASI spectral radiances, which exploit the high spectral resolution of the instrument and which effectively summarize information contained within the IASI spectrum. A Principal Component Analysis prior step is also introduced which makes the problem more consistent with the statistical assumptions of the methodology. An initial assessment of the scheme is performed based on global and regional IASI real data sets and cloud masks obtained from AVHRR (Advanced Very High Resolution Radiometer and SEVIRI (Spinning Enhanced Visible and Infrared Imager imagers. The agreement with these independent cloud masks is generally well above 80%, except at high latitudes in their winter seasons.

  13. Cloud mask via cumulative discriminant analysis applied to satellite infrared observations: scientific basis and initial evaluation

    Science.gov (United States)

    Amato, U.; Lavanant, L.; Liuzzi, G.; Masiello, G.; Serio, C.; Stuhlmann, R.; Tjemkes, S. A.

    2014-10-01

    We introduce a classification method (cumulative discriminant analysis) of the discriminant analysis type to discriminate between cloudy and clear-sky satellite observations in the thermal infrared. The tool is intended for the high-spectral-resolution infrared sounder (IRS) planned for the geostationary METEOSAT (Meteorological Satellite) Third Generation platform and uses IASI (Infrared Atmospheric Sounding Interferometer) data as a proxy. The cumulative discriminant analysis does not introduce biases intrinsic with the approximation of the probability density functions and is flexible enough to adapt to different strategies to optimize the cloud mask. The methodology is based on nine statistics computed from IASI spectral radiances, which exploit the high spectral resolution of the instrument and which effectively summarize information contained within the IASI spectrum. A principal component analysis prior step is also introduced, which makes the problem more consistent with the statistical assumptions of the methodology. An initial assessment of the scheme is performed based on global and regional IASI real data sets and cloud masks obtained from AVHRR (Advanced Very High Resolution Radiometer) and SEVIRI (Spinning Enhanced Visible and Infrared Imager) imagers. The agreement with these independent cloud masks is generally well above 80 %, except at high latitudes in the winter seasons.

  14. Evaluation of Impinging Stream Vortex Chamber Concepts for Liquid Rocket Engine Applications

    Science.gov (United States)

    Trinh, Huu P.; Bullard, Brad; Kopicz, Charles; Michaels, Scott

    2002-01-01

    for the liquid oxygen (LOX) hydrocarbon fuel (RP-1) system has been derived from the one for the gel propellant. An unlike impinging injector was employed to deliver the propellants to the chamber. MSFC is also conducting an alternative injection scheme, called the chasing injector, associated with this vortex chamber concept. In this injection technique, both propellant jets and their impingement point are in the same chamber cross-sectional plane. Long duration tests (approximately up to 15 seconds) will be conducted on the ISVC to study the thermal effects. This paper will report the progress of the subject efforts at NASA Marshall Space Flight Center. Thrust chamber performance and thermal wall compatibility will be evaluated. The chamber pressures, wall temperatures, and thrust will be measured as appropriate. The test data will be used to validate CFD models, which, in turn, will be used to design the optimum vortex chambers. Measurements in the previous tests showed that the chamber pressures vary significantly with radius. This is due to the existence of the vortices in the chamber flow field. Hence, the combustion efficiency may not be easily determined from chamber pressure. For this project, measured thrust data will be collected. The performance comparison will be in terms of specific impulse efficiencies. In addition to the thrust measurements, several pressure and temperature readings at various locations on the chamber head faceplate and the chamber wall will be made. The first injector and chamber were designed and fabricated based on the available data and experience gained during gel propellant system tests by the U.S. Army. The alternate injector for the ISVC was also fabricated. Hot-fire tests of the vortex chamber are about to start and are expected to complete in February of 2003 at the TS115 facility of MSFC.

  15. Satellite Communication.

    Science.gov (United States)

    Technology Teacher, 1985

    1985-01-01

    Presents a discussion of communication satellites: explains the principles of satellite communication, describes examples of how governments and industries are currently applying communication satellites, analyzes issues confronting satellite communication, links mathematics and science to the study of satellite communication, and applies…

  16. Concepts of ‘personalization’ in personalized medicine: implications for economic evaluation

    Science.gov (United States)

    Rogowski, Wolf; Payne, Katherine; Schnell-Inderst, Petra; Manca, Andrea; Rochau, Ursula; Jahn, Beate; Alagoz, Oguzhan; Leidl, Reiner; Siebert, Uwe

    2015-01-01

    Context This paper assesses if, and how, existing methods for economic evaluation are applicable to the evaluation of PM and if not, where extension to methods may be required. Method Structured workshop with a pre-defined group of experts (n=47), run using a modified nominal group technique. Workshop findings were recorded using extensive note taking and summarised using thematic data analysis. The workshop was complemented by structured literature searches. Results The key finding emerging from the workshop, using an economic perspective, was that two distinct, but linked, interpretations of the concept of PM exist (personalization by ‘physiology’ or ‘preferences’). These interpretations involve specific challenges for the design and conduct of economic evaluations. Existing evaluative (extra-welfarist) frameworks were generally considered appropriate for evaluating PM. When ‘personalization’ is viewed as using physiological biomarkers, challenges include: representing complex care pathways; representing spill-over effects; meeting data requirements such as evidence on heterogeneity; choosing appropriate time horizons for the value of further research in uncertainty analysis. When viewed as tailoring medicine to patient preferences, further work is needed regarding: revealed preferences, e.g. treatment (non)adherence; stated preferences, e.g. risk interpretation and attitude; consideration of heterogeneity in preferences; and the appropriate framework (welfarism vs. extra-welfarism) to incorporate non-health benefits. Conclusion Ideally, economic evaluations should take account of both interpretations of PM and consider physiology and preferences. It is important for decision makers to be cognizant of the issues involved with the economic evaluation of PM to appropriately interpret the evidence and target future research funding. PMID:25249200

  17. Intercomparison and evaluation of satellite peroxyacetyl nitrate observations in the upper troposphere-lower stratosphere

    Science.gov (United States)

    Pope, Richard J.; Richards, Nigel A. D.; Chipperfield, Martyn P.; Moore, David P.; Monks, Sarah A.; Arnold, Stephen R.; Glatthor, Norbert; Kiefer, Michael; Breider, Tom J.; Harrison, Jeremy J.; Remedios, John J.; Warneke, Carsten; Roberts, James M.; Diskin, Glenn S.; Huey, Lewis G.; Wisthaler, Armin; Apel, Eric C.; Bernath, Peter F.; Feng, Wuhu

    2016-11-01

    Peroxyacetyl nitrate (PAN) is an important chemical species in the troposphere as it aids the long-range transport of NOx and subsequent formation of O3 in relatively clean remote regions. Over the past few decades observations from aircraft campaigns and surface sites have been used to better understand the regional distribution of PAN. However, recent measurements made by satellites allow for a global assessment of PAN in the upper troposphere-lower stratosphere (UTLS). In this study, we investigate global PAN distributions from two independent retrieval methodologies, based on measurements from the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) instrument, on board Envisat from the Institute of Meteorology and Climate Research (IMK), Karlsruhe Institute of Technology, and the Department of Physics and Astronomy, University of Leicester (UoL). Retrieving PAN from MIPAS is challenging due to the weak signal in the measurements and contamination from other species. Therefore, we compare the two MIPAS datasets with observations from the Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS), in situ aircraft data and the 3-D chemical transport model TOMCAT. MIPAS shows peak UTLS PAN concentrations over the biomass burning regions (e.g. ranging from 150 to > 200 pptv at 150 hPa) and during the summertime Asian monsoon as enhanced convection aids the vertical transport of PAN from the lower atmosphere. At 150 hPa, we find significant differences between the two MIPAS datasets in the tropics, where IMK PAN concentrations are larger by 50-100 pptv. Comparisons between MIPAS and ACE-FTS show better agreement with the UoL MIPAS PAN concentrations at 200 hPa, but with mixed results above this altitude. TOMCAT generally captures the magnitude and structure of climatological aircraft PAN profiles within the observational variability allowing it to be used to investigate the MIPAS PAN differences. TOMCAT-MIPAS comparisons show that the

  18. Organic food processing: a framework for concept, starting definitions and evaluation.

    Science.gov (United States)

    Kahl, Johannes; Alborzi, Farnaz; Beck, Alexander; Bügel, Susanne; Busscher, Nicolaas; Geier, Uwe; Matt, Darja; Meischner, Tabea; Paoletti, Flavio; Pehme, Sirli; Ploeger, Angelika; Rembiałkowska, Ewa; Schmid, Otto; Strassner, Carola; Taupier-Letage, Bruno; Załęcka, Aneta

    2014-10-01

    In 2007 EU Regulation (EC) 834/2007 introduced principles and criteria for organic food processing. These regulations have been analysed and discussed in several scientific publications and research project reports. Recently, organic food quality was described by principles, aspects and criteria. These principles from organic agriculture were verified and adapted for organic food processing. Different levels for evaluation were suggested. In another document, underlying paradigms and consumer perception of organic food were reviewed against functional food, resulting in identifying integral product identity as the underlying paradigm and a holistic quality view connected to naturalness as consumers' perception of organic food quality. In a European study, the quality concept was applied to the organic food chain, resulting in a problem, namely that clear principles and related criteria were missing to evaluate processing methods. Therefore the goal of this paper is to describe and discuss the topic of organic food processing to make it operational. A conceptual background for organic food processing is given by verifying the underlying paradigms and principles of organic farming and organic food as well as on organic processing. The proposed definition connects organic processing to related systems such as minimal, sustainable and careful, gentle processing, and describes clear principles and related criteria. Based on food examples, such as milk with different heat treatments, the concept and definitions were verified. Organic processing can be defined by clear paradigms and principles and evaluated according criteria from a multidimensional approach. Further work has to be done on developing indicators and parameters for assessment of organic food quality.

  19. Concept Mapping as an Instrument for Evaluating an Instruction Unit on Holography (Concept Maps als Evaluierungsinstrumente einer Unterrichtseinheit zur Holographie)

    CERN Document Server

    Horn, M E; Horn, Martin Erik; Mikelskis, Helmut F.

    2004-01-01

    Due to its amazing three-dimensional effects, holography is a very motivating, yet very demanding subject for physics classes at the upper level in school. For this reason an instruction unit on holography that supplement holographic experiments with computer-supported work sessions and a simulation program was developed. The effects of the lessons on holography were determined by a pre-post-test design. In addition to videotaping the lessons, knowledge and motivational tests as well as student interviews, students were asked to prepare concept maps, which were used to track processes of model construction. The way this knowledge was applied largely depends on the students' understanding of models. In particular it was shown that the participating students' demonstrated capacity for distinguishing between the different models of light is of great importance. Only students with a developed capacity for distinguishing between models are able to reason in an problem-oriented manner. They recognize the limits of ...

  20. Development and Evaluation of Sensor Concepts for Ageless Aerospace Vehicles: Report 3 - Design of the Concept Demonstrator

    Science.gov (United States)

    Abbott, David; Ables, Jon; Batten, Adam; Carpenter, David; Collings, Tony; Doyle, Briony; Dunlop, John; Edwards, Graeme; Farmer, Tony; Gaffney, Bruce; Hedley, Mark; Isaacs, Peter; Johnson, Mark; Joshi, Bhautik; Lewis, Chris; Poilton, Geoff; Price, Don; Prokopenko, Mikhail; Reda, Torsten; Rees, David; Scott, Andrew; Seneviratne, Sarath; Valencia, Philip; Wang, Peter; Whitnall, Denis

    2008-01-01

    This report provides an outline of the essential features of a Structural Health Monitoring Concept Demonstrator (CD) that will be constructed during the next eight months. It is emphasized that the design cannot be considered to be complete, and that design work will continue in parallel with construction and testing. A major advantage of the modular design is that small modules of the system can be developed, tested and modified before a commitment is made to full system development. The CD is expected to develop and evolve for a number of years after its initial construction. This first stage will, of necessity, be relatively simple and have limited capabilities. Later developments will improve all aspects of the functionality of the system, including sensing, processing, communications, intelligence and response. The report indicates the directions this later development will take.

  1. Evaluating NOx emission inventories for regulatory air quality modeling using satellite and air quality model data

    Science.gov (United States)

    Kemball-Cook, Susan; Yarwood, Greg; Johnson, Jeremiah; Dornblaser, Bright; Estes, Mark

    2015-09-01

    The purpose of this study was to assess the accuracy of NOx emissions in the Texas Commission on Environmental Quality's (TCEQ) State Implementation Plan (SIP) modeling inventories of the southeastern U.S. We used retrieved satellite tropospheric NO2 columns from the Ozone Monitoring Instrument (OMI) together with NO2 columns from the Comprehensive Air Quality Model with Extensions (CAMx) to make top-down NOx emissions estimates using the mass balance method. Two different top-down NOx emissions estimates were developed using the KNMI DOMINO v2.0 and NASA SP2 retrievals of OMI NO2 columns. Differences in the top-down NOx emissions estimates made with these two operational products derived from the same OMI radiance data were sufficiently large that they could not be used to constrain the TCEQ NOx emissions in the southeast. The fact that the two available operational NO2 column retrievals give such different top-down NOx emissions results is important because these retrievals are increasingly being used to diagnose air quality problems and to inform efforts to solve them. These results reflect the fact that NO2 column retrievals are a blend of measurements and modeled data and should be used with caution in analyses that will inform policy development. This study illustrates both benefits and challenges of using satellite NO2 data for air quality management applications. Comparison with OMI NO2 columns pointed the way toward improvements in the CAMx simulation of the upper troposphere, but further refinement of both regional air quality models and the NO2 column retrievals is needed before the mass balance and other emission inversion methods can be used to successfully constrain NOx emission inventories used in U.S. regulatory modeling.

  2. Evaluating the Road Safety Design through High Resolution Satellite Image: A Case Study of Karachi Metropolitan

    Directory of Open Access Journals (Sweden)

    Zubair Salman

    2016-01-01

    Full Text Available Humanity is suffering from numerous natural, technological and health related hazards. Urban Road crash is one of the growing health issues these days in both developed and developing countries. Pakistan stands 1st in Asia and 48th in the world in this regard. Similarly, the metropolitan city of Pakistan, Karachi; ranks fourth in the list. Various reasons are responsible for these crashes in Karachi. Around 34% of crashes in the city were accounted due to errors in road geometry. In this study use of high resolution satellite imagery made it possible for identifying geometrical errors at the U-turns on major arteries of the city. It was also recognized that most of the U-turns were built on the fastest lane of the roads with average distance of 1.1 Km apart, are marked as vulnerable for considerable number of severe injury and fatal crashes. Moreover, inlet wall of all median U-turns were found broken, suggested that the car crash had occurred at least once. To cross check this observation, nearly 120 U-turns were surveyed and marked on the satellite imagery based on convenience. Trained professionals interviewed the people working/living nearby the U-turns. Out of 120 U-turns studied, 72.5% were without wall/median and 27.5% were with wall/median. Average number of people got injured or died due to crashes were statistically significant (p<0.05 between the above mentioned types of U-turns. In order to reduce geometrical errors use of RS (Remote Sensing and GIS (Geographical Information System techniques are strongly suggested to be incorporated while planning road design in the city. This would certainly save the resources particularly the lives of the people.

  3. Satellite orbit determination and gravity field recovery from satellite-to-satellite tracking

    Science.gov (United States)

    Wakker, K. F.; Ambrosius, B. A. C.; Leenman, H.

    1989-07-01

    Studies on satellite-to-satellite tracking (SST) with POPSAT (a geodetic satellite concept) and a ERS-class (Earth observation) satellite, a Satellite-to-Satellite Tracking (SST) gravity mission, and precise gravity field determination methods and mission requirements are reported. The first two studies primarily address the application of SST between the high altitude POPSAT and an ERS-class or GRM (Geopotential Research Mission) satellite to the orbit determination of the latter two satellites. Activities focussed on the determination of the tracking coverage of the lower altitude satellite by ground based tracking systems and by POPSAT, orbit determination error analysis and the determination of the surface forces acting on GRM. The third study surveys principles of SST, uncertainties of existing drag models, effects of direct luni-solar attraction and tides on orbit and the gravity gradient observable. Detailed ARISTOTELES (which replaced POPSAT) orbit determination error analyses were performed for various ground based tracking networks.

  4. Evaluation of Concepts for Mulitiple Application Thermal Reactor for Irradiation eXperiments (MATRIX)

    Energy Technology Data Exchange (ETDEWEB)

    Pope, Michael A. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Gougar, Hans D. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ryskamp, John M. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2013-09-01

    The Advanced Test Reactor (ATR) is a high power density test reactor specializing in fuel and materials irradiation. For more than 45 years, the ATR has provided irradiations of materials and fuels testing along with radioisotope production. Originally operated primarily in support of the Offcie of Naval Reactors (NR), the mission has gradually expanded to cater to other customers, such as the DOE Office of Nuclear Energy (NE), private industry, and universities. Unforeseen circumstances may lead to the decommissioning of ATR, thus leaving the U.S. Government without a large-scale materials irradiation capability to meet the needs of its nuclear energy and naval reactor missions. In anticipation of this possibility, work was performed under the Laboratory Directed Research and Development (LDRD) program to investigate test reactor concepts that could satisfy the current missions of the ATR along with an expanded set of secondary missions. This work can be viewed as an update to a project from the 1990’s called the Broad Application Test Reactor (BATR). In FY 2012, a survey of anticipated customer needs was performed, followed by analysis of the original BATR concepts with fuel changed to low-enriched uranium. Departing from these original BATR designs, four concepts were identified for further analysis in FY2013. The project informally adopted the acronym MATRIX (Multiple-Application Thermal Reactor for Irradiation eXperiments). This report discusses analysis of the four MATRIX concepts along with a number of variations on these main concepts. Designs were evaluated based on their satisfaction of anticipated customer requirements and the “Cylindrical” variant was selected for further analysis of options. This downselection should be considered preliminary and the backup alternatives should include the other three main designs. The baseline Cylindrical MATRIX design is expected to be capable of higher burnup than the ATR (or longer cycle length given a

  5. An Evaluation of Satellite-Based and Re-Analysis Radiation Budget Datasets Using CERES EBAF Products

    Science.gov (United States)

    Gupta, Shashi; Stackhouse, Paul; Wong, Takmeng; Mikovitz, Colleen; Cox, Stephen; Zhang, Taiping

    2016-04-01

    Top-of-atmosphere (TOA) and surface radiative fluxes from CERES Energy Balanced and Filled (EBAF; Loeb et al., 2009; Kato et al. 2013) products are used to evaluate the performance of several widely used long-term radiation budget datasets. Two of those are derived from satellite observations and five more are from re-analysis products. Satellite-derived datasets are the NASA/GEWEX Surface and TOA Radiation Budget Dataset Release-3 and the ISCCP-FD Dataset. The re-analysis datasets are taken from NCEP-CFSR, ERA-Interim, Japanese Re-Analysis (JRA-55), MERRA and the newly released MERRA2 products. Close examination is made of the differences between MERRA and MERRA2 products for the purpose of identifying improvements achieved for MERRA2. Many of these datasets have undergone quality assessment under the GEWEX Radiative Flux Assessment (RFA) project. For the purposes of the present study, EBAF datasets are treated as reference and other datasets are compared with it. All-sky and clear-sky, SW and LW, TOA and surface fluxes are included in this study. A 7-year period (2001-2007) common to all datasets is chosen for comparisons of global and zonal averages, monthly and annual average timeseries, and their anomalies. These comparisons show significant differences between EBAF and the other datasets. Certain anomalies and trends observed in the satellite-derived datasets are attributable to corresponding features in satellite datasets used as input, especially ISCCP cloud properties. Comparisons of zonal averages showed significant differences especially over higher latitudes even when those differences are not obvious in the global averages. Special emphasis is placed on the analysis of the correspondence between spatial patterns of geographical distribution of the above fluxes on a 7-year average as well as on a month-by-month basis using the Taylor (2001) methodology. Results showed that for 7-year average fields correlation coefficients between spatial patterns

  6. An Evaluation of Antarctica as a Calibration Target for Passive Microwave Satellite Missions with Climate Data Record Applications

    Science.gov (United States)

    Kim, E. J.

    2011-12-01

    surface salinity, both important climate variables. Science studies involving these variables can now take advantage of new satellite L-band observations. The first mission with regular global passive microwave observations at L-band is the European Space Agency's Soil Moisture and Ocean Salinity (SMOS), launched November, 2009. A second mission, NASA's Aquarius, was launched June, 2011. A third mission, NASA's Soil Moisture Active Passive (SMAP) is scheduled to launch in 2014. Together, these three missions may provide a decade-long data record-provided that they are intercalibrated. The intercalibration is best performed at the radiance (brightness temperature) level, and Antarctica is proving to be a key calibration target. However, Antarctica has thus far not been fully characterized as a potential target. This paper will present evaluations of Antarctica as a microwave calibration target for the above satellite missions. Preliminary analyses have identified likely target areas, such as the vicinity of Dome-C and larger areas within East Antarctica. Physical sources of temporal and spatial variability of polar firn are key to assessing calibration uncertainty. These sources include spatial variability of accumulation rate, compaction, surface characteristics (dunes, micro-topography), wind patterns, and vertical profiles of density and temperature. Using primarily SMOS data, variability is being empirically characterized and attempts are being made to attribute observed variability to physical sources. One expected outcome of these studies is the potential discovery of techniques for remotely sensing--over all of Antarctica-parameters such as surface temperature.

  7. Evaluation of the feasibility of security technologies in teleradiology as biometric fingerprint scanners for data exchange over a satellite WAN

    Science.gov (United States)

    Soegner, Peter I.; Helweg, Gernot; Holzer, Heimo; zur Nedden, Dieter

    2000-05-01

    We evaluated the feasibility of fingerprint-scanners in combination with smart cards for personal identification and transmission of encrypted TCP/IP-data-packages via satellite between the university-hospital of Innsbruck and the rural hospital of Reutte. The aim of our study was the proof of the userfriendliness of the SkymedTM technology for security purpose in teleradiology. We examined the time of the personal identification process, the time for the necessary training and the personal satisfaction. The images were sent from the local PACS in Reutte via a Data-Encryption-and-Transmission- Box via satellite from Reutte to Innsbruck. We used an asymmetric bandwidth of 512 kbit/s from Reutte to Innsbruck and 128 kbit/s in the opposite direction. Window NT 4.0- operating PCs were used for the electronical patient record, the medical inquiry of the referring physician and the final report of the radiologist. The images were reported on an UNIX-PACS viewing station. After identification through fingerprint-scanners in combination with the smart card the radiologist was able to open the electronic patient record (EPR) from Reutte and sign with his digital signature his confirmed final report before it was send back to Reutte. The used security technology enables encrypted communication over a WAN, which fulfill data-protection.

  8. Extended Plate and Beam Wall System: Concept Investigation and Initial Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Wiehagen, J. [Partnership for Home Innovation, Upper Marlboro, MD (United States); Kochkin, V. [Partnership for Home Innovation, Upper Marlboro, MD (United States)

    2015-08-01

    A new and innovative High-R wall design, referred to as the Extended Plate & Beam (EP&B), is under development. The EP&B system uniquely integrates foam sheathing insulation with wall framing such that wood structural panels are installed exterior of the foam sheathing, enabling the use of standard practices for installation of drainage plane, windows and doors, claddings, cavity insulation, and the standard exterior foam sheathing installation approach prone to damage of the foam during transportation of prefabricated wall panels. As part of the ongoing work, the EP&B wall system concept has undergone structural verification testing and has been positively vetted by a group of industry stakeholders. Having passed these initial milestone markers, the advanced wall system design has been analyzed to assess cost implications relative to other advanced wall systems, undergone design assessment to develop construction details, and has been evaluated to develop representative prescriptive requirements for the building code. This report summarizes the assessment steps conducted to-date and provides details of the concept development.

  9. Extended Plate and Beam Wall System: Concept Investigation and Initial Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Wiehagen, J. [Partnership for Home Innovation, Upper Marlboro, MD (United States); Kochkin, V. [Partnership for Home Innovation, Upper Marlboro, MD (United States)

    2015-08-01

    A new and innovative High-R wall design, referred to as the Extended Plate & Beam (EP&B), is under development. The EP&B system uniquely integrates foam sheathing insulation with wall framing such that wood structural panels are installed exterior of the foam sheathing, enabling the use of standard practices for installation of drainage plane, windows and doors, claddings, cavity insulation, and the standard exterior foam sheathing installation approach prone to damage of the foam during transportation of prefabricated wall panels. As part of the ongoing work, the EP&B wall system concept has undergone structural verification testing and has been positively vetted by a group of industry stakeholders. Having passed these initial milestone markers, the advanced wall system design has been analyzed to assess cost implications relative to other advanced wall systems, undergone design assessment to develop construction details, and has been evaluated to develop representative prescriptive requirements for the building code. This report summarizes the assessment steps conducted to-date and provides details of the concept development.

  10. Infrared chemical imaging: Spatial resolution evaluation and super-resolution concept

    Energy Technology Data Exchange (ETDEWEB)

    Offroy, Marc [Laboratoire de Spectrochimie Infrarouge et Raman, LASIR, CNRS UMR 8516, Bat. C5, Universite des Sciences et Technologies de Lille, 59655 Villeneuve d' Ascq Cedex (France); Roggo, Yves [F. Hoffmann-La Roche A.G., Basel (Switzerland); Milanfar, Peyman [Multi-Dimensional Signal Processing Laboratory, Electrical Engineering Department, Baskin School of Engineering, University of California, 1156 High Street, Mailcode SOE2, Santa Cruz, CA 95064 (United States); Duponchel, Ludovic, E-mail: ludovic.duponchel@univ-lille1.fr [Laboratoire de Spectrochimie Infrarouge et Raman, LASIR, CNRS UMR 8516, Bat. C5, Universite des Sciences et Technologies de Lille, 59655 Villeneuve d' Ascq Cedex (France)

    2010-08-03

    Chemical imaging systems help to solve many challenges in various scientific fields. Able to deliver rapid spatial and chemical information, modern infrared spectrometers using Focal Plane Array detectors (FPA) are of great interest. Considering conventional infrared spectrometers with a single element detector, we can consider that the diffraction-limited spatial resolution is more or less equal to the wavelength of the light (i.e. 2.5-25 {mu}m). Unfortunately, the spatial resolution of FPA spectroscopic setup is even lower due to the detector pixel size. This becomes a real constraint when micron-sized samples are analysed. New chemometrics methods are thus of great interest to overcome such resolution drawback, while keeping our far-field infrared imaging spectrometers. The aim of the present work is to evaluate the super-resolution concept in order to increase the spatial resolution of infrared imaging spectrometers using FPA detectors. The main idea of super-resolution is the fusion of several low-resolution images of the same sample to obtain a higher-resolution image. Applying the super-resolution concept on a relatively low number of FPA acquisitions, it was possible to observe a 30% decrease in spatial resolution.

  11. Evaluation of Empirical Tropospheric Models Using Satellite-Tracking Tropospheric Wet Delays with Water Vapor Radiometer at Tongji, China.

    Science.gov (United States)

    Wang, Miaomiao; Li, Bofeng

    2016-02-02

    An empirical tropospheric delay model, together with a mapping function, is commonly used to correct the tropospheric errors in global navigation satellite system (GNSS) processing. As is well-known, the accuracy of tropospheric delay models relies mainly on the correction efficiency for tropospheric wet delays. In this paper, we evaluate the accuracy of three tropospheric delay models, together with five mapping functions in wet delays calculation. The evaluations are conducted by comparing their slant wet delays with those measured by water vapor radiometer based on its satellite-tracking function (collected data with large liquid water path is removed). For all 15 combinations of three tropospheric models and five mapping functions, their accuracies as a function of elevation are statistically analyzed by using nine-day data in two scenarios, with and without meteorological data. The results show that (1) no matter with or without meteorological data, there is no practical difference between mapping functions, i.e., Chao, Ifadis, Vienna Mapping Function 1 (VMF1), Niell Mapping Function (NMF), and MTT Mapping Function (MTT); (2) without meteorological data, the UNB3 is much better than Saastamoinen and Hopfield models, while the Saastamoinen model performed slightly better than the Hopfield model; (3) with meteorological data, the accuracies of all three tropospheric delay models are improved to be comparable, especially for lower elevations. In addition, the kinematic precise point positioning where no parameter is set up for tropospheric delay modification is conducted to further evaluate the performance of tropospheric delay models in positioning accuracy. It is shown that the UNB3 model is best and can achieve about 10 cm accuracy for the N and E coordinate component while 20 cm accuracy for the U coordinate component no matter the meteorological data is available or not. This accuracy can be obtained by the Saastamoinen model only when meteorological data is

  12. Evaluation of Empirical Tropospheric Models Using Satellite-Tracking Tropospheric Wet Delays with Water Vapor Radiometer at Tongji, China

    Directory of Open Access Journals (Sweden)

    Miaomiao Wang

    2016-02-01

    Full Text Available An empirical tropospheric delay model, together with a mapping function, is commonly used to correct the tropospheric errors in global navigation satellite system (GNSS processing. As is well-known, the accuracy of tropospheric delay models relies mainly on the correction efficiency for tropospheric wet delays. In this paper, we evaluate the accuracy of three tropospheric delay models, together with five mapping functions in wet delays calculation. The evaluations are conducted by comparing their slant wet delays with those measured by water vapor radiometer based on its satellite-tracking function (collected data with large liquid water path is removed. For all 15 combinations of three tropospheric models and five mapping functions, their accuracies as a function of elevation are statistically analyzed by using nine-day data in two scenarios, with and without meteorological data. The results show that (1 no matter with or without meteorological data, there is no practical difference between mapping functions, i.e., Chao, Ifadis, Vienna Mapping Function 1 (VMF1, Niell Mapping Function (NMF, and MTT Mapping Function (MTT; (2 without meteorological data, the UNB3 is much better than Saastamoinen and Hopfield models, while the Saastamoinen model performed slightly better than the Hopfield model; (3 with meteorological data, the accuracies of all three tropospheric delay models are improved to be comparable, especially for lower elevations. In addition, the kinematic precise point positioning where no parameter is set up for tropospheric delay modification is conducted to further evaluate the performance of tropospheric delay models in positioning accuracy. It is shown that the UNB3 model is best and can achieve about 10 cm accuracy for the N and E coordinate component while 20 cm accuracy for the U coordinate component no matter the meteorological data is available or not. This accuracy can be obtained by the Saastamoinen model only when

  13. Comparison and evaluation of satellite- and reanalysis-based precipitation products for water resources management in the Brahmaputra River basin

    Science.gov (United States)

    Saleh Khan, Abu; Sohel Masud, Md.; Abdulla Hel Kafi, Md.; Sultana, Tashrifa; Lopez Lopez, Patricia

    2017-04-01

    The Brahmaputra River, with a transboundary basin area of approx. 554,500 km2, has its origin on the northern slope of the Himalayas in China, from where it flows through India, Bhutan and finally Bangladesh. Brahmaputra basin's climatology is heavily conditioned by precipitation during the monsoon months, concentrating about the 85 % of the rainfall in this period and originating severe and frequent floods that impact specially the Bangladeshi population in the delta region. Recent campaigns to increase the quality and to share ground-based hydro-meteorological data, in particular precipitation, within the basin have provided limited results. Global rainfall data from satellite and reanalysis may improve the temporal and spatial availability of in-situ observations for advanced water resources management. This study aims to evaluate the applicability of several global precipitation products from satellite and reanalysis in comparison with in-situ data to quantify their added value for hydrological modeling at a basin and sub-basin scale for the Brahmaputra River. Precipitation products from CMORPH, TRMM-3B42, GsMAP, WFDEI, MSWEP and various combinations with ground-based data were evaluated at basin and sub-basin level at a daily and monthly temporal resolution. The Brahmaputra was delineated into 54 sub-basins for a more detailed evaluation of the precipitation products. The data were analysed and inter-compared for the time period from 2002 to 2010. Precipitation performance assessment was conducted including several indicators, such as probability of detection (POD), false alarm ratio (FAR), Pearson's correlation coefficient (r), bias and root mean square error (RMSE). Preliminary results indicate high correlation and low bias and RMSE values between WFDEI, TRMM-3B42 and CMORPH precipitation and in-situ observations at a monthly time scale. Lower correlations and higher bias and RMSE values were found between GsMAP and MSWEP and ground-observed precipitation

  14. [Concept for a bioclimatic evaluation of an expedition and trekking area at moderate and high altitudes].

    Science.gov (United States)

    Lazar, Reinhold

    2005-04-01

    This paper presents a concept which is built up on climate data with a long period of observation (temperature, wind conditions, precipitation, irradiation, and the frequency of low pressure weather situations with unfavorable biotropy stages). It therefore allows an evaluation of the bioclimate of a high mountain area. With the help of this relatively simple method, the risk of problems like AMS can be better estimated. Latest comparisons between different agencies of expeditions show that often the time schedule for climbing to the summit is too short and allows too little time for acclimatization; furthermore the number of days allowed for recreation is too small. A comparison of selected alpine regions shows better conditions in, for example, the Mount Kenia/Kilimandjaro region and parts of the western Andes in Chile, whereas the Himalaya and the Karakorum group can be problematic.

  15. An evaluation of the pressure proof test concept for 2024-T3 aluminium alloy sheet

    Science.gov (United States)

    Dawicke, D. S.; Poe, C. C., Jr.; Newman, J. C.; Harris, C. E.

    1991-01-01

    The concept of pressure proof testing of fuselage structures with fatigue cracks to insure structural integrity was evaluated from a fracture mechanics viewpoint. A generic analytical and experimental investigation was conducted on uniaxially loaded flat panels with crack configurations and stress levels typical of longitudinal lap splice joints in commercial transport aircraft fuselages. The results revealed that the remaining fatigue life after a proof cycle was longer than that without the proof cycle because of crack growth retardation due to increased crack closure. However, based on a crack length that is slightly less than the critical value at the maximum proof stress, the minimum assured life or proof test interval must be no more than 550 pressure cycles for a 1.33 proof factor and 1530 pressure cycles for a 1.5 proof factor to prevent in-flight failures.

  16. Concept development evaluation for John Deere/UA STS middeck experiment location

    Science.gov (United States)

    Youngblood, W. W.

    1985-01-01

    The purpose of this effort was to consider and evaluate some specific concepts for performing a number of extremely low gravity (i.e., microgravity) experiments involving the directional solidification of samples of high carbon, cast iron alloys. The specific experiments considered herein were conceived to permit scientific investigation of the resultant microstructures and mechanical properties of the test samples after the microgravity environment processing. This study was limited to consideration of the NASA/MSFC furnace payloads, referred to herein as the Automated Directional Solidification Furnace (ADSF) systems. Three ADSF systems were reviewed and are as follows: (1) Low temperature ADSF (ADSF-1); (2) High temperature ADSF (ADSF-2); and (3) Advanced ADSF (AADSF).

  17. Methodology for Performance Evaluation of Pre Departure Sequencing Tools in terms of A-CDM concept

    Directory of Open Access Journals (Sweden)

    Hynek Hrabík

    2017-01-01

    Full Text Available The article describes the proposed methodology for performance evaluation of Pre-Departure Sequencing tools. Pre-departure management delivers optimal traffic flow to the runway by route planning and accurate taxi time forecasts. Firstly, a Pre-Departure Sequencer Start-Up Manager (SUM used by Air Navigation Services of the Czech Republic (ANS CZ at Vaclav Havel Airport Prague (LKPR is mentioned. The main parts deal with the proposed methodology for performance evaluation of Start-Up Manager. The methodology uses several indicators to evaluate the performance. The methodology utilizes time milestones introduced in Airport Collaborative Decision Making (A-CDM concept. It focuses especially on aircraft pre-departure sequencing processes. Methodology was tested on the Start-Up Manager used by Air Navigation Services (ANS of the Czech Republic at Vaclav Havel Airport Prague (LKPR. Achieved performance results and its credibility in accordance with the proposed methodology are presented and discussed in the final part of this paper.

  18. Organic food quality: a framework for concept, definition and evaluation from the European perspective.

    Science.gov (United States)

    Kahl, Johannes; Baars, Ton; Bügel, Susanne; Busscher, Nicolaas; Huber, Machteld; Kusche, Daniel; Rembiałkowska, Ewa; Schmid, Otto; Seidel, Kathrin; Taupier-Letage, Bruno; Velimirov, Alberta; Załecka, Aneta

    2012-11-01

    Consumers buy organic food because they believe in the high quality of the product. Furthermore, the EU legal regulatory framework for organic food and farming defines high quality of the products as an important goal of production. A major challenge is the need to define food quality concepts and methods for determination. A background is described which allows embedding of the quality definitions as well as evaluation methods into a conceptual framework connected to the vision and mission of organic agriculture and food production. Organic food quality is defined through specific aspects and criteria. For evaluation each criterion has to be described by indicators. The determination of indicators should be through parameters, where parameters are described by methods. Conversely, the conceptual framework is described according to underlying principles and starting definitions are given, but further work has do be done on the detailed scientific description of the indicators. Furthermore, parameters have to be defined for the evaluation of suitability of these indicators for organic food production. Copyright © 2012 Society of Chemical Industry.

  19. Evaluation of Academic Self-Concept Scale With "Online Decision Support System For Counseling Services"

    Directory of Open Access Journals (Sweden)

    Salman ÇAKIR

    2013-12-01

    Full Text Available Guidance and psychological consultancy services in Turkish education system is basically oriented students to realize their skills and prove themselves, to benefit from the process of education in top level according to their talents and qualifications, to use and improve their potential in most convenient way. Leading students to the jobs according to their characteristics, interests and talents defines the fate of countries and communities. Individuals discover their interests and talents and they are guided to professions according to those interests and talents with the Scale of Academic Self-Concept (SASC that is the one of implements used in vocational guidance at schools. Application of these assessment and evaluation instruments in schools brings about paper waste, increases stationer expenses and takes guidance counselors’ time too much during the evaluation phase. (SODSGS that is enhanced in this practice, the system of online decision and support for guidance service, resolves most of these problems mentioned before. SODSGS is added with SASC that is used for vocational guidance in schools and evaluation criteria. In an attempt to test the system whether it is working properly, they are compared and contrasted with the results that guidance counselor acquired before, by loading survey data implemented in 2010-2011 education period. It is observed that results of SODSGS and guidance counselors’ are coherent with each other. Using SASC through SODSGS will be beneficial in terms of expenditure, time and credibility at schools

  20. New concepts for phase I trials: evaluating new drugs combined with radiation therapy.

    Science.gov (United States)

    Deutsch, Eric; Soria, Jean Charles; Armand, Jean Pierre

    2005-09-01

    The rationale for delivering concomitant chemoradiation is not only to increase tumor cell kill but also to achieve a synergistic effect of chemotherapy and radiation. Combination of chemotherapy and radiotherapy has yielded encouraging results in patients with locally advanced diseases. Our increased knowledge of cancer at the molecular level has transformed our understanding of tumor radiation resistance. Preclinical models have shown that several biologic agents designed to target specifically these molecular processes are radiosensitizing agents. Many of these agents are in the process of clinical evaluation with radiotherapy. The translation of these findings into the clinical setting will be feasible only if early phase I trials demonstrate their safety when combined with ionizing radiation. The combination of new drugs and radiation might not necessarily be equivalent to the toxicity of the new drug plus the usual toxicity of radiation. The doses and schedule to be explored for the new drug might vary from those assessed for the new drug alone. Inappropriate evaluation of a combination regimen can result in unjustified abandonment of a combination, or adoption of a regimen at toxic dose levels because of poor toxicity monitoring. Beside the 'in field' radiation dose-dependent symptoms, 'outside the field' symptoms that are not dose dependent might be identified. Specific and long-term clinical evaluation will be required to identify potentially harmful interactions. It will be necessary to rethink phase I strategies, toxicity endpoints, and trial designs and concepts in order to fully optimize these regimens.

  1. External Vision Systems (XVS) proof-of-concept flight test evaluation

    Science.gov (United States)

    Shelton, Kevin J.; Williams, Steven P.; Kramer, Lynda J.; Arthur, Jarvis J.; Prinzel, Lawrence; Bailey, Randall E.

    2014-06-01

    NASA's Fundamental Aeronautics Program, High Speed Project is performing research, development, test and evaluation of flight deck and related technologies to support future low-boom, supersonic configurations (without forward-facing windows) by use of an eXternal Vision System (XVS). The challenge of XVS is to determine a combination of sensor and display technologies which can provide an equivalent level of safety and performance to that provided by forward-facing windows in today's aircraft. This flight test was conducted with the goal of obtaining performance data on see-and-avoid and see-to-follow traffic using a proof-of-concept XVS design in actual flight conditions. Six data collection flights were flown in four traffic scenarios against two different sized participating traffic aircraft. This test utilized a 3x1 array of High Definition (HD) cameras, with a fixed forward field-of-view, mounted on NASA Langley's UC-12 test aircraft. Test scenarios, with participating NASA aircraft serving as traffic, were presented to two evaluation pilots per flight - one using the proof-of-concept (POC) XVS and the other looking out the forward windows. The camera images were presented on the XVS display in the aft cabin with Head-Up Display (HUD)-like flight symbology overlaying the real-time imagery. The test generated XVS performance data, including comparisons to natural vision, and post-run subjective acceptability data were also collected. This paper discusses the flight test activities, its operational challenges, and summarizes the findings to date.

  2. External Vision Systems (XVS) Proof-of-Concept Flight Test Evaluation

    Science.gov (United States)

    Shelton, Kevin J.; Williams, Steven P.; Kramer, Lynda J.; Arthur, Jarvis J.; Prinzel, Lawrence, III; Bailey, Randall E.

    2014-01-01

    NASA's Fundamental Aeronautics Program, High Speed Project is performing research, development, test and evaluation of flight deck and related technologies to support future low-boom, supersonic configurations (without forward-facing windows) by use of an eXternal Vision System (XVS). The challenge of XVS is to determine a combination of sensor and display technologies which can provide an equivalent level of safety and performance to that provided by forward-facing windows in today's aircraft. This flight test was conducted with the goal of obtaining performance data on see-and-avoid and see-to-follow traffic using a proof-of-concept XVS design in actual flight conditions. Six data collection flights were flown in four traffic scenarios against two different sized participating traffic aircraft. This test utilized a 3x1 array of High Definition (HD) cameras, with a fixed forward field-of-view, mounted on NASA Langley's UC-12 test aircraft. Test scenarios, with participating NASA aircraft serving as traffic, were presented to two evaluation pilots per flight - one using the proof-of-concept (POC) XVS and the other looking out the forward windows. The camera images were presented on the XVS display in the aft cabin with Head-Up Display (HUD)-like flight symbology overlaying the real-time imagery. The test generated XVS performance data, including comparisons to natural vision, and post-run subjective acceptability data were also collected. This paper discusses the flight test activities, its operational challenges, and summarizes the findings to date.

  3. EVALUATION OF TUNA FISHING GROUND IN SOUTHERN COAST OF JAVA - SUMBAWA SEA USING SATELLITE OBSERVED DATA

    Directory of Open Access Journals (Sweden)

    MOKHLAS SATIBI

    2012-11-01

    Full Text Available Potential fishery in territorial water of South Java - Sumbawa Sea has not been exploited maximally. Tuna is one of fisherypotency in the territorial water of South Java - Sumbawa. Tuna is the important economic value because it represent one ofexporting commodity enthused by overseas consumer.Research was conducted in the Southern Java – Sumbawa, Indian Ocean 90 S - 160 S; 1060 E - 1210 E, using fish catch data2003 – 2006. Research location is in the inclusive Region of Fishery Management IX (DKP and PKSPL, 2003. Data weretaken from a daily fish catch of PT. Perikanan Samudra Besar (PSB Benoa Bali 2003 - 2006.Sea level anomaly (SLA data were estimated from Altimetry satellite (Jason 1, wind speed data was from Scatterometersatellite and sea surface temperature (SST data was from Microwave satellite.Based on the result of this research, sea level anomaly of southern coast of Java-Sumbawa was fluctuated according tomonsoon. The highest bigeye tuna fish catched was 40 tuna in June 2003 and the lowest bigeye tuna fish was 2 tuna inNovember 2005. Maximum SLA observe during southeast monsoon was 21.77 cm in august 2005, while minimum SLAobserved during southeast monsoon was -18.15 cm in October 2003. Sea surface temperature of southern coast of Java-Sumbawa also fluctuated according to monsoon. Maximum SST observed during northwest monsoon was 30.450 C in March2006, while minimum SST observed during southeast monsoon was 25.050 C in August 2006. The highest wind speed was10.20 m/sec in June 2004 and the lowest was 2.00 m/sec in October 2004. Wind direction was reversely changed according tomonsoon. Northwest wind monsoon flew eastward and southeast wind monsoon flew westward.Fish production in PT PSB had been done over 4 years since 2003, in northwest and southwest monsoon in constant areaand correlation of linier regression among estimate of fish catching using SLA, SST and wind speed had no correlation. Withfish production during southwest

  4. The Satellite Based Hydrological Model (SHM): Routing Scheme and its Evaluation

    Science.gov (United States)

    kumari, Nikul; Paul, Pranesh Kumar; Singh, Rajendra; Panigrahy, Niranjan; Mishra, Ashok; Gupta, Praveen Kumar; Singh, Raghavendra P.

    2016-04-01

    The collection of spatially extensive data by using the traditional methods of data acquisition is a challenging task for a large territory like India. To overcome such problems, the Satellite based Hydrological Model (SHM), a large scale conceptual hydrological model for the Indian Territory, is being developed under the PRACRITI-2 program of the Space Applications Centre (SAC), Ahmedabad. The model aims at preparing sustainable water management scenarios using remote sensing data from Indian satellites to handle the fresh water crisis in India. There are five modules namely, Surface Water (SW), Forest (F), Snow (S), Groundwater (GW) and Routing (ROU) in the SHM. The SW, F and S modules convert rainfall into surface runoff and generate input (infiltration and percolation) for the GW module, and GW generates baseflow using that input. In this study, a cell-to-cell routing (ROU) module has been developed for SHM. It is based on the principle of Time Variant Spatially Distributed Direct Hydrograph (SDDH) to route the generated runoff and baseflow generated by various modules upto the outlet. The entire India is divided into 5km x 5km grid cells and properties at the center of the cell are assumed to represent the property of the cell. In the routing scheme, for each cell a single downstream cell is defined in the direction of steepest descent, to create the flow network. These grid cells are classified into overland cells and channel cells based on the threshold value taken into consideration. The overland flow travel time of each overland cell is estimated by combining a steady state kinematic wave approximation with Manning's equation and the channel flow travel time of each channel cell is estimated using Manning's equation and the steady state continuity equation. The travel time for each cell is computed by dividing the travel distance through that cell with cell velocity. The cumulative travel time from each grid cell to the watershed outlet is the sum of

  5. A NOVEL SAFER CONCEPTION COUNSELING TOOLKIT FOR THE PREVENTION OF HIV: A MIXED-METHODS EVALUATION IN KISUMU, KENYA

    Science.gov (United States)

    Brown, Joelle; Njoroge, Betty; Akama, Eliud; Breitnauer, Brooke; Leddy, Anna; Darbes, Lynae; Omondi, Richard; Mmeje, Okeoma

    2017-01-01

    Safer conception strategies can prevent HIV transmission between HIV-discordant partners while allowing them to conceive. However, HIV care providers in sub-Saharan Africa report they are not trained in safer conception, and patients are not routinely offered safer conception services. This mixed-methods pilot study evaluated the impact, acceptability, and feasibility of a novel Safer Conception Counseling Toolkit among providers and patients in Kenya. We enrolled 20 HIV-positive women, 10 HIV-discordant couples, and 10 providers from HIV care and treatment clinics. Providers completed questionnaires before/after training, and then counseled HIV-affected patients. Change in patient knowledge was assessed before/after counseling. Qualitative interviews were conducted among providers and patients. The Toolkit was associated with large, significant increases in patient knowledge, and provider confidence, knowledge, and favorable attitudes toward safer conception counseling; 20% felt confident before versus 100% after training (p < 0.01). PMID:27925487

  6. The GNSS polarimetric radio-occultation technique to sense precipitation events: a new concept to be tested aboard PAZ Low Earth Satellite

    Science.gov (United States)

    Tomás, Sergio; Oliveras, Santi; Cardellach, Estel; Rius, Antonio

    2013-04-01

    The Radio Occultation and Heavy Precipitation (ROHP) experiment, to be conducted aboard the Spanish PAZ satellite, consists of a radio occultation (RO) mission provided with dual-polarization capabilities. The research with polarimetric RO data has the goal of assessing the capabilities and limitations of this technique to infer profiles of heavy precipitation. The technique aims to provide vertical profiles of precipitation simultaneously to the vertical profiles of thermodynamic parameters (standard RO products) perfectly collocated both in space and time. If successful, the polarimetric RO will represent the first technique able to provide these complementary information on precipitation. This is a relevant input for studies on heavy and violent rainfall events, which being poorly represented by the current-generation of Numerical Weather Prediction and General Circulation Models appear to be difficult to forecast on all time-scales. The Low Earth Orbiter hosting this experiment, to be launched in 2013, will orbit at 500 km altitude in a near-Polar orbit. The Radio Occulation payload includes a RO GNSS receiver and a dual polarization (H/V) limb oriented antenna to capture the signals of setting GNSS transmitters. NOAA and UCAR participate in the ground-segment of the radiometric experiment to enable near-real time dissemination of the level-1 standard RO products. The space-based GNSS RO technique scans the atmosphere vertically at fine resolution (close to 300 meter in the troposphere) by precisely measure the delay between a GNSS transmitter and a GNSS receiver aboard a Low Earth Orbiter, when the former is setting below or rising above the Earth limb. The standard, thermodynamical, products are extracted from the excess delay induced by the atmosphere at different layers. This presentation will not focus on this well-established application, but a novel concept using polarimetry to also retrieve rain information. The precipitation-measurement principle is

  7. Evaluating the Impact of Smoke Particle Absorption on Passive Satellite Cloud Optical Depth Retrievals

    Science.gov (United States)

    Alfaro-Contreras, R.; Zhang, J.; Reid, J. S.; Campbell, J. R.

    2013-12-01

    Absorbing aerosol particles, when lifted above clouds, can perturb top-of-atmosphere radiation radiances measured by passive satellite sensors through the absorption of reflected solar energy. This scenario, if not properly screened, impacts cloud physical retrievals, like cloud optical depth (COD), conducted using radiances/channels in the visible spectrum. We describe observations of smoke particle presence above cloud off the southwest coast of Africa, using spatially and temporally collocated Aqua Moderate Resolution Imaging Spectroradiometer (AQUA MODIS), Ozone Monitoring Instrument (OMI) and Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) measurements. Results from this study indicate that above cloud aerosol episodes happen rather frequent in the smoke outflow region during the Northern Hemisphere summer where above cloud aerosol plumes introduce a significant bias to MODIS COD retrievals in the visible spectrum. This suggests that individual COD retrievals as well as COD climatology from MODIS can be affected over the smoke outflow region by above cloud aerosol contamination and thus showing the need to account for the presence of above cloud absorbing aerosols in the MODIS visible COD retrievals.

  8. The evaluation of pharmacist-technician teams applied to a satellite pharmacy.

    Science.gov (United States)

    Kershaw, B P; Zarowitz, B J; Solomon, D K; Mouzakis, M M

    1989-01-01

    The team work group design has been suggested as a mechanism to integrate clinical and distributive pharmacy services, expand clinical roles, enhance staff satisfaction, and promote resource efficiency. A pharmacist-technician team was created at Henry Ford Hospital, Detroit, and the effects of the team were assessed via pre and post data collection of attitudinal, behavioral and pharmacy service aspects. Each of three satellite teams were responsible for all pharmacy services to a target group of patients. The results of the team design include a significant decrease in pharmacist and technician perceptions of role stress, especially in the categories of role overload, role isolation, and role ambiguity, and less total hours of work lost by pharmacists (54% improved) and technicians (29% improved). The nurses perceived slightly better pharmacy services upon survey, although not statistically significant, and IV solution wastage decreased 5.6%. Clinical pharmacist compliance to standards of practice was unchanged in spite of increased supervisional responsibilities. We were able to show that the pharmacist-technician team design decreased stress and created more efficient pharmacy services.

  9. Evaluation of a size-resolved aerosol model based on satellite and ground observations and its implication on aerosol forcing

    Science.gov (United States)

    Ma, Xiaoyan; Yu, Fangqun

    2016-04-01

    The latest AeroCom phase II experiments have showed a large diversity in the simulations of aerosol concentrations, size distribution, vertical profile, and optical properties among 16 detailed global aerosol microphysics models, which contribute to the large uncertainty in the predicted aerosol radiative forcing and possibly induce the distinct climate change in the future. In the last few years, we have developed and improved a global size-resolved aerosol model (Yu and Luo, 2009; Ma et al., 2012; Yu et al., 2012), GEOS-Chem-APM, which is a prognostic multi-type, multi-component, size-resolved aerosol microphysics model, including state-of-the-art nucleation schemes and condensation of low volatile secondary organic compounds from successive oxidation aging. The model is one of 16 global models for AeroCom phase II and participated in a couple of model inter-comparison experiments. In this study, we employed multi-year aerosol optical depth (AOD) data from 2004 to 2012 taken from ground-based Aerosol Robotic Network (AERONET) measurements and Moderate Resolution Imaging Spectroradiometer (MODIS), Multiangle Imaging SpectroRadiometer (MISR) and Sea-viewing Wide Field-of-view Sensor (SeaWiFS) satellite retrievals to evaluate the performance of the GEOS-Chem-APM in predicting aerosol optical depth, including spatial distribution, reginal variation and seasonal variabilities. Compared to the observations, the modelled AOD is overall good over land, but quite low over ocean possibly due to low sea salt emission in the model and/or higher AOD in satellite retrievals, specifically MODIS and MISR. We chose 72 AERONET sites having at least 36 months data available and representative of high spatial domain to compare with the model and satellite data. Comparisons in various representative regions show that the model overall agrees well in the major anthropogenic emission regions, such as Europe, East Asia and North America. Relative to the observations, the modelled AOD is

  10. Concept Maps as a Research and Evaluation Tool To Assess Conceptual Change in Quantum Physics.

    Science.gov (United States)

    Sen, Ahmet Ilhan

    2002-01-01

    Informs teachers about using concept maps as a learning tool and alternative assessment tools in education. Presents research results of how students might use concept maps to communicate their cognitive structure. (Author/KHR)

  11. Concept Mapping as a Research Tool to Evaluate Conceptual Change Related to Instructional Methods

    Science.gov (United States)

    Miller, Kevin J.; Koury, Kevin A.; Fitzgerald, Gail E.; Hollingsead, Candice; Mitchem, Katherine J.; Tsai, Hui-Hsien; Park, Meeaeng Ko

    2009-01-01

    Concept maps are commonly used in a variety of educational settings as a learning aid or instructional tool. Additionally, their potential as a research tool has been recognized. This article defines features of concept maps, describes the use of pre- and postconcept maps as a research tool, and offers a protocol for employing concept maps as an…

  12. Evaluation of the ISBA-TRIP continental hydrologic system over the Niger basin using in situ and satellite derived datasets

    Science.gov (United States)

    Pedinotti, V.; Boone, A.; Decharme, B.; Crétaux, J. F.; Mognard, N.; Panthou, G.; Papa, F.; Tanimoun, B. A.

    2012-06-01

    During the 1970s and 1980s, West Africa has faced extreme climate variations with extended drought conditions. Of particular importance is the Niger basin, since it traverses a large part of the Sahel and is thus a critical source of water for an ever-increasing local population in this semi arid region. However, the understanding of the hydrological processes over this basin is currently limited by the lack of spatially distributed surface water and discharge measurements. The purpose of this study is to evaluate the ability of the ISBA-TRIP continental hydrologic system to represent key processes related to the hydrological cycle of the Niger basin. ISBA-TRIP is currently used within a coupled global climate model, so that the scheme must represent the first order processes which are critical for representing the water cycle while retaining a limited number of parameters and a simple representation of the physics. To this end, the scheme uses first-order approximations to account explicitly for the surface river routing, the floodplain dynamics, and the water storage using a deep aquifer reservoir. In the current study, simulations are done at a 0.5 by 0.5° spatial resolution over the 2002-2007 period (in order to take advantage of the recent satellite record and data from the African Monsoon Multidisciplinary Analyses project, AMMA). Four configurations of the model are compared to evaluate the separate impacts of the flooding scheme and the aquifer on the water cycle. Moreover, the model is forced by two different rainfall datasets to consider the sensitivity of the model to rainfall input uncertainties. The model is evaluated using in situ discharge measurements as well as satellite derived flood extent, total continental water storage changes and river height changes. The basic analysis of in situ discharges confirms the impact of the inner delta area, known as a significant flooded area, on the discharge, characterized by a strong reduction of the

  13. Evaluation of the ISBA-TRIP continental hydrologic system over the Niger basin using in situ and satellite derived datasets

    Directory of Open Access Journals (Sweden)

    V. Pedinotti

    2012-06-01

    Full Text Available During the 1970s and 1980s, West Africa has faced extreme climate variations with extended drought conditions. Of particular importance is the Niger basin, since it traverses a large part of the Sahel and is thus a critical source of water for an ever-increasing local population in this semi arid region. However, the understanding of the hydrological processes over this basin is currently limited by the lack of spatially distributed surface water and discharge measurements. The purpose of this study is to evaluate the ability of the ISBA-TRIP continental hydrologic system to represent key processes related to the hydrological cycle of the Niger basin. ISBA-TRIP is currently used within a coupled global climate model, so that the scheme must represent the first order processes which are critical for representing the water cycle while retaining a limited number of parameters and a simple representation of the physics. To this end, the scheme uses first-order approximations to account explicitly for the surface river routing, the floodplain dynamics, and the water storage using a deep aquifer reservoir. In the current study, simulations are done at a 0.5 by 0.5° spatial resolution over the 2002–2007 period (in order to take advantage of the recent satellite record and data from the African Monsoon Multidisciplinary Analyses project, AMMA. Four configurations of the model are compared to evaluate the separate impacts of the flooding scheme and the aquifer on the water cycle. Moreover, the model is forced by two different rainfall datasets to consider the sensitivity of the model to rainfall input uncertainties. The model is evaluated using in situ discharge measurements as well as satellite derived flood extent, total continental water storage changes and river height changes. The basic analysis of in situ discharges confirms the impact of the inner delta area, known as a significant flooded area, on the discharge, characterized by a strong

  14. Drought resistance across California ecosystems: Evaluating changes in carbon dynamics using satellite imagery

    Science.gov (United States)

    Malone, Sparkle; Tulbure, Mirela; Pérez-Luque, Antonio J.; Assal, Timothy J.; Bremer, Leah; Drucker, Debora; Hillis, Vicken; Varela, Sara; Goulden, Michael

    2016-01-01

    Drought is a global issue that is exacerbated by climate change and increasing anthropogenic water demands. The recent occurrence of drought in California provides an important opportunity to examine drought response across ecosystem classes (forests, shrublands, grasslands, and wetlands), which is essential to understand how climate influences ecosystem structure and function. We quantified ecosystem resistance to drought by comparing changes in satellite-derived estimates of water-use efficiency (WUE = net primary productivity [NPP]/evapotranspiration [ET]) under normal (i.e., baseline) and drought conditions (ΔWUE = WUE2014 − baseline WUE). With this method, areas with increasing WUE under drought conditions are considered more resilient than systems with declining WUE. Baseline WUE varied across California (0.08 to 3.85 g C/mm H2O) and WUE generally increased under severe drought conditions in 2014. Strong correlations between ΔWUE, precipitation, and leaf area index (LAI) indicate that ecosystems with a lower average LAI (i.e., grasslands) also had greater C-uptake rates when water was limiting and higher rates of carbon-uptake efficiency (CUE = NPP/LAI) under drought conditions. We also found that systems with a baseline WUE ≤ 0.4 exhibited a decline in WUE under drought conditions, suggesting that a baseline WUE ≤ 0.4 might be indicative of low drought resistance. Drought severity, precipitation, and WUE were identified as important drivers of shifts in ecosystem classes over the study period. These findings have important implications for understanding climate change effects on primary productivity and C sequestration across ecosystems and how this may influence ecosystem resistance in the future.

  15. Evaluation of water vapor distribution in general circulation models using satellite observations

    Science.gov (United States)

    Soden, Brian J.; Bretherton, Francis P.

    1994-01-01

    This paper presents a comparison of the water vapor distribution obtained from two general circulation models, the European Centre for Medium-Range Weather Forecasts (ECMWF) model and the National Center for Atmospheric Research (NCAR) Community Climate Model (CCM), with satellite observations of total precipitable water (TPW) from Special Sensor Microwave/Imager (SSM/I) and upper tropospheric relative humidity (UTH) from GOES. Overall, both models are successful in capturing the primary features of the observed water vapor distribution and its seasonal variation. For the ECMWF model, however, a systematic moist bias in TPW is noted over well-known stratocumulus regions in the eastern subtropical oceans. Comparison with radiosonde profiles suggests that this problem is attributable to difficulties in modeling the shallowness of the boundary layer and large vertical water vapor gradients which characterize these regions. In comparison, the CCM is more successful in capturing the low values of TPW in the stratocumulus regions, although it tends to exhibit a dry bias over the eastern half of the subtropical oceans and a corresponding moist bias in the western half. The CCM also significantly overestimates the daily variability of the moisture fields in convective regions, suggesting a problem in simulating the temporal nature of moisture transport by deep convection. Comparison of the monthly mean UTH distribution indicates generally larger discrepancies than were noted for TPW owing to the greater influence of large-scale dynamical processes in determining the distribution of UTH. In particular, the ECMWF model exhibits a distinct dry bias along the Intertropical Convergence Zone (ITCZ) and a moist bias over the subtropical descending branches of the Hadley cell, suggesting an underprediction in the strength of the Hadley circulation. The CCM, on the other hand, demonstrates greater discrepancies in UTH than are observed for the ECMWF model, but none that are as

  16. Evaluation of multiple satellite evaporation products in two dryland regions using GRACE

    KAUST Repository

    Lopez, Oliver

    2015-12-01

    Remote sensing has become a valuable tool for monitoring the water cycle variables in areas that lack the availability of ground-based measurements. Integrating multiple remote sensing-based estimates of evaporation, precipitation, and the terrestrial water storage changes with local measurements of streamflow into a consistent estimate of the regional water budget is a challenge, due to the scale mismatch among the retrieved variables. Evapotranspiration, including soil evaporation, interception losses and canopy transpiration, has received special focus in a number of recent studies that aim to provide global or regional estimates of evaporation at regular time intervals using a variety of remote sensing input. In arid and semi-arid regions, modeling of evaporation is particularly challenging due to the relatively high role of the soil evaporation component in these regions and the variable nature of rainfall events that drive the evaporation process. In this study, we explore the hydrological consistency of remote sensing products in terms of water budget closure and the correlation among spatial patterns of precipitation (P), evaporation (E) and terrestrial water storage, using P-E as a surrogate of water storage changes, with special attention to the evaporation component. The analysis is undertaken within two dryland regions that have presented recent significant changes in climatology (Murray-Darling Basin in Australia) and water storage (the Saq aquifer in northern Saudi Arabia). Water storage changes were derived from the Gravity Recovery and Climate Experiment (GRACE) spherical harmonic (SH) coefficients. Six remote sensing-based evaporation estimates were subtracted from the Global Precipitation Climatology Project (GPCP)-based precipitation estimates and were compared with GRACE-derived water storage changes. Our results suggest that it is not possible to close the water balance by using satellite data alone, even when adopting a spherical harmonic

  17. Evaluation of TRMM satellite-based precipitation indexes for flood forecasting over Riyadh City, Saudi Arabia

    Science.gov (United States)

    Tekeli, Ahmet Emre; Fouli, Hesham

    2016-10-01

    Floods are among the most common disasters harming humanity. In particular, flash floods cause hazards to life, property and any type of structures. Arid and semi-arid regions are equally prone to flash floods like regions with abundant rainfall. Despite rareness of intensive and frequent rainfall events over Kingdom of Saudi Arabia (KSA); an arid/semi-arid region, occasional flash floods occur and result in large amounts of damaging surface runoff. The flooding of 16 November, 2013 in Riyadh; the capital city of KSA, resulted in killing some people and led to much property damage. The Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) Real Time (RT) data (3B42RT) are used herein for flash flood forecasting. 3B42RT detected high-intensity rainfall events matching with the distribution of observed floods over KSA. A flood early warning system based on exceedance of threshold limits on 3B42RT data is proposed for Riyadh. Three different indexes: Constant Threshold (CT), Cumulative Distribution Functions (CDF) and Riyadh Flood Precipitation Index (RFPI) are developed using 14-year 3B42RT data from 2000 to 2013. RFPI and CDF with 90% captured the three major flooding events that occurred in February 2005, May 2010 and November 2013 in Riyadh. CT with 3 mm/h intensity indicated the 2013 flooding, but missed those of 2005 and 2010. The methodology implemented herein is a first-step simple and accurate way for flash flood forecasting over Riyadh. The simplicity of the methodology enables its applicability for the TRMM follow-on missions like Global Precipitation Measurement (GPM) mission.

  18. The continuing challenge of evaluating diastolic function by echocardiography in children: developing concepts and newer modalities.

    Science.gov (United States)

    Mawad, Wadi; Friedberg, Mark K

    2017-01-01

    Assessment of diastolic function by echocardiography is challenging but important. Left ventricular filling has been more extensively studied than the right ventricle, and predominantly in adult populations. Although multiple parameters exist to assess diastolic function, they all have limitations, including load and heart rate dependency, which make assessment of diastolic function particularly challenging. The purpose of this article is to review evolving concepts and modalities for echo assessment of diastolic function in children. The paradigm whereby diastolic dysfunction severity progresses in a staged fashion from impaired relaxation to increasing ventricular stiffness, may not apply in children. In addition, previous adult guidelines are not readily applicable to children with cardiomyopathy and the applicability of the newly revised adult guidelines needs to be evaluated in children. It is unlikely that any one single echocardiographic diastolic parameter will adequately reflect diastolic function. Hence, parameters derived from atrioventricular valve inflow, pulmonary venous, and tissue Doppler need to be integrated. Newer modalities such as diastolic strain rate and rotation mechanics may be useful as more sensitive markers of early ventricular dysfunction but have important limitations and require more evaluation before routine use in practice. Assessment of systolic-diastolic coupling may enhance assessment of diastolic function. Diastolic function impacts outcomes and should be part of routine echocardiographic assessment of function. An integrative approach combining different parameters, possibly with contribution of newer modalities in the future, is required.

  19. Invited Article: Concepts and tools for the evaluation of measurement uncertainty

    Science.gov (United States)

    Possolo, Antonio; Iyer, Hari K.

    2017-01-01

    Measurements involve comparisons of measured values with reference values traceable to measurement standards and are made to support decision-making. While the conventional definition of measurement focuses on quantitative properties (including ordinal properties), we adopt a broader view and entertain the possibility of regarding qualitative properties also as legitimate targets for measurement. A measurement result comprises the following: (i) a value that has been assigned to a property based on information derived from an experiment or computation, possibly also including information derived from other sources, and (ii) a characterization of the margin of doubt that remains about the true value of the property after taking that information into account. Measurement uncertainty is this margin of doubt, and it can be characterized by a probability distribution on the set of possible values of the property of interest. Mathematical or statistical models enable the quantification of measurement uncertainty and underlie the varied collection of methods available for uncertainty evaluation. Some of these methods have been in use for over a century (for example, as introduced by Gauss for the combination of mutually inconsistent observations or for the propagation of "errors"), while others are of fairly recent vintage (for example, Monte Carlo methods including those that involve Markov Chain Monte Carlo sampling). This contribution reviews the concepts, models, methods, and computations that are commonly used for the evaluation of measurement uncertainty, and illustrates their application in realistic examples drawn from multiple areas of science and technology, aiming to serve as a general, widely accessible reference.

  20. Formation Flying Concept Issues

    Directory of Open Access Journals (Sweden)

    M. V. Palkin

    2015-01-01

    Full Text Available The term “formation flying” implies coordinated movement of at least two satellites on coplanar and non-coplanar orbits with a maximum distance between them being much less than the length of the orbit. Peculiarities of formation flying concept also include:- automatic coordination of satellites;- sub-group specialization of formation flying satellites;- equipment and data exchange technology unification in each specialized group or subgroup.Formation flying satellites can be classified according to the configuration stability level (order (array, cluster («swarm», intergroup specialization rules («central satellite», «leader», «slave», manoeuvrability («active» and «passive» satellites.Tasks of formation flying include:- experiments with payload, distributed in formation flying satellites;- various near-earth space and earth-surface research;- super-sized aperture antenna development;- land-based telescope calibration;- «space advertisement» (earth-surface observable satellite compositions of a logotype, word, etc.;- orbital satellite maintenance, etc.Main issues of formation flying satellite system design are:- development of an autonomous satellite group manoeuvring technology;- providing a sufficient characteristic velocity of formation flying satellites;- ballistic and navigation maintenance for satellite formation flying;- technical and economic assessment of formation flying orbital delivery and deployment;- standardization, unification, miniaturization and integration of equipment;- intergroup and intersatellite function redistribution.

  1. Ground-based & satellite DOAS measurements integration for air quality evaluation/forecast management in the frame of QUITSAT Project.

    Science.gov (United States)

    Kostadinov, Ivan; Petritoli, Andrea; Giovanelli, Giorgio; Masieri, Samuele; Premuda, Margarita; Bortoli, Daniele; Ravegnani, Fabrizio; Palazzi, Elisa

    The observations of the Earth's atmosphere from space provide excellent opportunities for the exploration of the sophisticated physical-chemical processes on both global and regional scales. The major interest during the last three decades was focused mainly on the stratosphere and the ozone depletion. More recently the continuous improvements of satellite sensors have revealed new opportunities for larger applications of space observations, attracting scientific interest to the lower troposphere and air quality issues. The air quality depends strongly on the anthropogenic activity and therefore regional environmental agencies along with policy makers are in need of appropriate means for its continuous monitoring and control to ensure the adoption of the most appropriate actions. The goal of the pilot project QUITSAT, funded by the Italian Space Agency, is to develop algorithms and procedures for the evaluation and prediction of the air quality in Lombardia and Emilia-Romagna regions (Italy) by means of integrating satellite observations with ground-based in-situ and remote sensing measurements. This work presents dedicated Differential Optical Absorption Spectroscopy (DOAS) measurements performed during the summer of 2007 and the winter of 2008. One of the DOAS instruments operate at Mt.Cimone station (2165m a.s.l) and the other two instruments conducted measurements in/near Bologna (90 m. a.s.l). Different observational geometry was adopted (zenith-sky, multi-axis and long-path) aimed to provide tropospheric NO2 columns and O3, SO2 and HCHO concentrations at ground level as an input data for QUITSAT procedures. Details of the instruments, the radiative transfer model used and the algorithms for retrieving and calculation of the target gases concentrations are presented. The obtained experimental results are correlated with the corresponding ones retrieved from SCIAMACHY /ENVISAT observations during the overpasses above the ground-based instruments. The analysis

  2. Evaluating the Capacity of Global CO2 Flux and Atmospheric Transport Models to Incorporate New Satellite Observations

    Science.gov (United States)

    Kawa, S. R.; Collatz, G. J.; Erickson, D. J.; Denning, A. S.; Wofsy, S. C.; Andrews, A. E.

    2007-01-01

    As we enter the new era of satellite remote sensing for CO2 and other carbon cyclerelated quantities, advanced modeling and analysis capabilities are required to fully capitalize on the new observations. Model estimates of CO2 surface flux and atmospheric transport are required for initial constraints on inverse analyses, to connect atmospheric observations to the location of surface sources and sinks, and ultimately for future projections of carbon-climate interactions. For application to current, planned, and future remotely sensed CO2 data, it is desirable that these models are accurate and unbiased at time scales from less than daily to multi-annual and at spatial scales from several kilometers or finer to global. Here we focus on simulated CO2 fluxes from terrestrial vegetation and atmospheric transport mutually constrained by analyzed meteorological fields from the Goddard Modeling and Assimilation Office for the period 1998 through 2006. Use of assimilated meteorological data enables direct model comparison to observations across a wide range of scales of variability. The biospheric fluxes are produced by the CASA model at lxi degrees on a monthly mean basis, modulated hourly with analyzed temperature and sunlight. Both physiological and biomass burning fluxes are derived using satellite observations of vegetation, burned area (as in GFED-2), and analyzed meteorology. For the purposes of comparison to CO2 data, fossil fuel and ocean fluxes are also included in the transport simulations. In this presentation we evaluate the model's ability to simulate CO2 flux and mixing ratio variability in comparison to in situ observations at sites in Northern mid latitudes and the continental tropics. The influence of key process representations is inferred. We find that the model can resolve much of the hourly to synoptic variability in the observations, although there are limits imposed by vertical resolution of boundary layer processes. The seasonal cycle and its

  3. Evaluation of soil and vegetation response to drought using SMOS soil moisture satellite observations

    Science.gov (United States)

    Piles, Maria; Sánchez, Nilda; Vall-llossera, Mercè; Ballabrera, Joaquim; Martínez, Justino; Martínez-Fernández, José; Camps, Adriano; Font, Jordi

    2014-05-01

    Soil moisture plays an important role in determining the likelihood of droughts and floods that may affect an area. Knowledge of soil moisture distribution as a function of time and space is highly relevant for hydrological, ecological and agricultural applications, especially in water-limited or drought-prone regions. However, measuring soil moisture is challenging because of its high variability; point-scale in-situ measurements are scarce being remote sensing the only practical means to obtain regional- and global-scale soil moisture estimates. The ESA's Soil Moisture and Ocean Salinity (SMOS) is the first satellite mission ever designed to measuring the Earth's surface soil moisture at near daily time scales with levels of accuracy previously not attained. Since its launch in November 2009, significant efforts have been dedicated to validate and fine-tune the retrieval algorithms so that SMOS-derived soil moisture estimates meet the standards required for a wide variety of applications. In this line, the SMOS Barcelona Expert Center (BEC) is distributing daily, monthly, and annual temporal averages of 0.25-deg global soil moisture maps, which have proved useful for assessing drought and water-stress conditions. In addition, a downscaling algorithm has been developed to combine SMOS and NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) data into fine-scale (stress conditions. In previous research, SMOS-derived Soil Moisture Anomalies (SSMA), calculated in a ten-day basis, were shown to be in close relationship with well-known drought indices (the Standardized Precipitation Index and the Standardized Precipitation Evapotranspiration Index). In this work, SSMA have been calculated for the period 2010-2013 in representative arid, semi-arid, sub-humid and humid areas across global land biomes. The SSMA reflect the cumulative precipitation anomalies and is known to provide 'memory' in the climate and hydrological system; the water retained in the soil

  4. Comparison and evaluation of satellite derived precipitation products for hydrological modeling of the Zambezi River Basin

    Directory of Open Access Journals (Sweden)

    T. Cohen Liechti

    2011-08-01

    Full Text Available In the framework of the African Dams ProjecT (ADAPT, an integrated water resource management study in the Zambezi Basin is currently under development. In view of the sparse gauging network for rainfall monitoring, the observations from spaceborne instrumentation currently produce the only available rainfall data for a large part of the basin.

    Three operational and acknowledged high resolution satellite derived estimates: the Tropical Rainfall Measuring Mission product 3B42 (TRMM 3B42, the Famine Early Warning System product 2.0 (FEWS RFE2.0 and the National Oceanic and Atmospheric Administration/Climate Prediction Centre (NOAA/CPC morphing technique (CMORPH are analyzed in terms of spatial and temporal repartition of the precipitations. They are compared to ground data for the wet seasons of the years 2003 to 2009 on a point to pixel basis at daily, 10-daily and monthly time steps and on a pixel to pixel basis for the wet seasons of the years 2003 to 2007 at monthly time steps.

    The general North-South gradient of precipitation is captured by all the analyzed products. Regarding the spatial heterogeneity, FEWS pixels are much more inter-correlated than TRMM and CMORPH pixels. For a rainfall homogeneity threshold criterion of 0.5 global mean correlation coefficient, the area of each subbasin should not exceed a circle of 2.5° latitude/longitude radius for FEWS and a circle of 0.75° latitude/longitude radius for TRMM and CMORPH considering rectangular mesh.

    In terms of reliability, the correspondence of all estimates with ground data increases with the time step chosen for the analysis. The volume ratio computation indicates that CMORPH is overestimating by nearly 1.5 times the rainfall. The statistics of TRMM and FEWS estimates show quite similar results.

    Due to the its lower inter-correlation and longer data set, the TRMM 3B42 product is chosen as input for the hydraulic-hydrologic model of the basin.

  5. Continuous evaluation of land cover restoration of tsunami struck plains in Japan by using several kinds of optical satellite image in time series

    Science.gov (United States)

    Hashiba, H.

    2015-09-01

    The Mw 9.0 earthquake that struck Japan in 2011 was followed by a large-scale tsunami in the Tohoku region. The damage in the coastal plane was extensively displayed through many satellite images. Furthermore, satellite imaging is requested for the ongoing evaluation of the restoration process. The reconstruction of the urban structure, farmlands, grassland, and coastal forest that collapsed under the large tsunami requires effective long-term monitoring. Moreover, the post-tsunami land cover dynamics can be effectively modeled using time-constrained satellite data to establish a prognosis method for the mitigation of future tsunami impact. However, the remote satellite capture of a long-term restoration process is compromised by accumulating spatial resolution effects and seasonal influences. Therefore, it is necessary to devise a method for data selection and dataset structure. In the present study, the restoration processes were investigated in four years following the disaster in a part of the Sendai plain, northeast Japan, from same-season satellite images acquired by different optical sensors. Coastal plains struck by the tsunami are evaluated through land-cover classification processing using the clustering method. The changes in land cover are analyzed from time-series optical images acquired by Landsat-5/TM, 7/ETM+, 8/OLI, EO-1/ALI, and ALOS-1/AVNIR-2. The study reveals several characteristics of the change in the inundation area and signs of artificial and natural restoration.

  6. Evaluating the performance of real-time streamflow forecasting using multi-satellite precipitation products in the Upper Zambezi, Africa

    Science.gov (United States)

    Demaria, E. M.; Valdes, J. B.; Wi, S.; Serrat-Capdevila, A.; Valdés-Pineda, R.; Durcik, M.

    2016-12-01

    In under-instrumented basins around the world, accurate and timely forecasts of river streamflows have the potential of assisting water and natural resource managers in their management decisions. The Upper Zambezi river basin is the largest basin in southern Africa and its water resources are critical to sustainable economic growth and poverty reduction in eight riparian countries. We present a real-time streamflow forecast for the basin using a multi-model-multi-satellite approach that allows accounting for model and input uncertainties. Three distributed hydrologic models with different levels of complexity: VIC, HYMOD_DS, and HBV_DS are setup at a daily time step and a 0.25 degree spatial resolution for the basin. The hydrologic models are calibrated against daily observed streamflows at the Katima-Mulilo station using a Genetic Algorithm. Three real-time satellite products: Climate Prediction Center's morphing technique (CMORPH), Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks (PERSIANN), and Tropical Rainfall Measuring Mission (TRMM-3B42RT) are bias-corrected with daily CHIRPS estimates. Uncertainty bounds for predicted flows are estimated with the Inverse Variance Weighting method. Because concentration times in the basin range from a few days to more than a week, we include the use of precipitation forecasts from the Global Forecasting System (GFS) to predict daily streamflows in the basin with a 10-days lead time. The skill of GFS-predicted streamflows is evaluated and the usefulness of the forecasts for short term water allocations is presented.

  7. Evaluation of three satellite-based latent heat flux algorithms over forest ecosystems using eddy covariance data.

    Science.gov (United States)

    Yao, Yunjun; Zhang, Yuhu; Zhao, Shaohua; Li, Xianglan; Jia, Kun

    2015-06-01

    We have evaluated the performance of three satellite-based latent heat flux (LE) algorithms over forest ecosystems using observed data from 40 flux towers distributed across the world on all continents. These are the revised remote sensing-based Penman-Monteith LE (RRS-PM) algorithm, the modified satellite-based Priestley-Taylor LE (MS-PT) algorithm, and the semi-empirical Penman LE (UMD-SEMI) algorithm. Sensitivity analysis illustrates that both energy and vegetation terms has the highest sensitivity compared with other input variables. The validation results show that three algorithms demonstrate substantial differences in algorithm performance for estimating daily LE variations among five forest ecosystem biomes. Based on the average Nash-Sutcliffe efficiency and root-mean-squared error (RMSE), the MS-PT algorithm has high performance over both deciduous broadleaf forest (DBF) (0.81, 25.4 W/m(2)) and mixed forest (MF) (0.62, 25.3 W/m(2)) sites, the RRS-PM algorithm has high performance over evergreen broadleaf forest (EBF) (0.4, 28.1 W/m(2)) sites, and the UMD-SEMI algorithm has high performance over both deciduous needleleaf forest (DNF) (0.78, 17.1 W/m(2)) and evergreen needleleaf forest (ENF) (0.51, 28.1 W/m(2)) sites. Perhaps the lower uncertainties in the required forcing data for the MS-PT algorithm, the complicated algorithm structure for the RRS-PM algorithm, and the calibrated coefficients of the UMD-SEMI algorithm based on ground-measured data may explain these differences.

  8. An Evaluation of Antarctica as a Calibration Target for Passive Microwave Satellite Missions with Climate Data Record Applications

    Science.gov (United States)

    Kim, Edward

    2011-01-01

    Passive microwave remote sensing at L-band (1.4 GHz) is sensitive to soil moisture and sea surface salinity, both important climate variables. Science studies involving these variables can now take advantage of new satellite L-band observations. The first mission with regular global passive microwave observations at L-band is the European Space Agency's Soil Moisture and Ocean Salinity (SMOS), launched November, 2009. A second mission, NASA's Aquarius, was launched June, 201 I. A third mission, NASA's Soil Moisture Active Passive (SMAP) is scheduled to launch in 2014. Together, these three missions may provide a decade-long data record-provided that they are intercalibrated. The intercalibration is best performed at the radiance (brightness temperature) level, and Antarctica is proving to be a key calibration target. However, Antarctica has thus far not been fully characterized as a potential target. This paper will present evaluations of Antarctica as a microwave calibration target for the above satellite missions. Preliminary analyses have identified likely target areas, such as the vicinity of Dome-C and larger areas within East Antarctica. Physical sources of temporal and spatial variability of polar firn are key to assessing calibration uncertainty. These sources include spatial variability of accumulation rate, compaction, surface characteristics (dunes, micro-topography), wind patterns, and vertical profiles of density and temperature. Using primarily SMOS data, variability is being empirically characterized and attempts are being made to attribute observed variability to physical sources. One expected outcome of these studies is the potential discovery of techniques for remotely sensing--over all of Antarctica-parameters such as surface temperature.

  9. Evaluation of World View-2 Satellite Data for Mapping Seaweed Beds Along Karachi Coast

    Science.gov (United States)

    Danish Siddiqui, Muhammad; Abdullah, Muhammad

    2016-07-01

    study. STUDY AREA Buleji, a small coastal village along Karachi coast in the country of Pakistan, is selected for this study. At this side seaweed resources are present. Its center lies at a latitude of 24o 51' 20" and a longitude of 66o 48' 24.2" METHODOLOGY In this research, high-resolution Worldview -2 satellite data have been used.WorldView-2 delivers 1.85 meter multispectral and 0.46 meter panchromatic images. A 0.5 meter multispectral pan sharpened image was developed by fusing these two images. Indices, such as normalized difference vegetative index (NDVI) and another index developed through spectral signatures, have been applied on worldview-2 imagery. Image enhancement technique, principal component analysis (PCA) is applied on the same image. Bathymetry map of the study area has been composed by relative bathymetry remote sensing technique. This map is later verified by the depth nautical chart and found satisfactory. For assessment of environmental parameters, freely available MODIS daily SST product has been acquired. MODIS product was converted to tiff (Tagged Image File Format) format and projected for further processing. SST image was reclassified using GIS technique and was overlaid on satellite images to detect the favorable temperature range for seaweed growth. CONCLUSION Since the macro-habitats and benthic communities around Pakistan coastline have not yet been properly mapped and defined, this study will be an outline for the protection of marine biodiversity and habitat of many sea species which rely on seaweeds for their sustenance. Regular monitoring and mapping are important to regulate the growth of seaweeds and their dependent species to maintain their biological associations which will eventually maintain the equilibrium among various species in the marine ecosystem. Seaweed is also important for the production of many consumable items and with proper import/export policies its marketing can ultimately help strengthen the country's economy

  10. Evaluating satellite imagery-based land use data for describing forestland development in western Washington

    Science.gov (United States)

    Jeffrey D. Kline; Alissa Moses; David L. Azuma; Andrew. Gray

    2009-01-01

    Forestry professionals are concerned about how forestlands are affected by residential and other development. To address those concerns, researchers must find appropriate data with which to describe and evaluate rates and patterns of forestland development and the impact of development on the management of remaining forestlands. We examine land use data gathered from...

  11. Evaluation of ACCMIP ozone simulations and ozonesonde sampling biases using a satellite-based multi-constituent chemical reanalysis

    Science.gov (United States)

    Miyazaki, Kazuyuki; Bowman, Kevin

    2017-07-01

    The Atmospheric Chemistry Climate Model Intercomparison Project (ACCMIP) ensemble ozone simulations for the present day from the 2000 decade simulation results are evaluated by a state-of-the-art multi-constituent atmospheric chemical reanalysis that ingests multiple satellite data including the Tropospheric Emission Spectrometer (TES), the Microwave Limb Sounder (MLS), the Ozone Monitoring Instrument (OMI), and the Measurement of Pollution in the Troposphere (MOPITT) for 2005-2009. Validation of the chemical reanalysis against global ozonesondes shows good agreement throughout the free troposphere and lower stratosphere for both seasonal and year-to-year variations, with an annual mean bias of less than 0.9 ppb in the middle and upper troposphere at the tropics and mid-latitudes. The reanalysis provides comprehensive spatiotemporal evaluation of chemistry-model performance that compliments direct ozonesonde comparisons, which are shown to suffer from significant sampling bias. The reanalysis reveals that the ACCMIP ensemble mean overestimates ozone in the northern extratropics by 6-11 ppb while underestimating by up to 18 ppb in the southern tropics over the Atlantic in the lower troposphere. Most models underestimate the spatial variability of the annual mean lower tropospheric concentrations in the extratropics of both hemispheres by up to 70 %. The ensemble mean also overestimates the seasonal amplitude by 25-70 % in the northern extratropics and overestimates the inter-hemispheric gradient by about 30 % in the lower and middle troposphere. A part of the discrepancies can be attributed to the 5-year reanalysis data for the decadal model simulations. However, these differences are less evident with the current sonde network. To estimate ozonesonde sampling biases, we computed model bias separately for global coverage and the ozonesonde network. The ozonesonde sampling bias in the evaluated model bias for the seasonal mean concentration relative to global

  12. A Space Based Solar Power Satellite System

    Science.gov (United States)

    Engel, J. M.; Polling, D.; Ustamujic, F.; Yaldiz, R.; et al.

    2002-01-01

    (SPoTS) supplying other satellites with energy. SPoTS is due to be commercially viable and operative in 2020. of Technology designed the SPoTS during a full-time design period of six weeks as a third year final project. The team, organized according to the principles of systems engineering, first conducted a literature study on space wireless energy transfer to select the most suitable candidates for use on the SPoTS. After that, several different system concepts have been generated and evaluated, the most promising concept being worked out in greater detail. km altitude. Each SPoTS satellite has a 50m diameter inflatable solar collector that focuses all received sunlight. Then, the received sunlight is further redirected by means of four pointing mirrors toward four individual customer satellites. A market-analysis study showed, that providing power to geo-stationary communication satellites during their eclipse would be most beneficial. At arrival at geo-stationary orbit, the focused beam has expended to such an extent that its density equals one solar flux. This means that customer satellites can continue to use their regular solar arrays during their eclipse for power generation, resulting in a satellite battery mass reduction. the customer satellites in geo-stationary orbit, the transmitted energy beams needs to be pointed with very high accuracy. Computations showed that for this degree of accuracy, sensors are needed, which are not mainstream nowadays. Therefore further research must be conducted in this area in order to make these high-accuracy-pointing systems commercially attractive for use on the SPoTS satellites around 2020. Total 20-year system lifetime cost for 18 SPoT satellites are estimated at approximately USD 6 billion [FY2001]. In order to compete with traditional battery-based satellite power systems or possible ground based wireless power transfer systems the price per kWh for the customer must be significantly lower than the present one

  13. The TAOS/STEP Satellite

    OpenAIRE

    Edwards, David; Hosken, Robert

    1995-01-01

    The Technology for Autonomous Operational Survivability / Space Test Experiments Platform (TAOS/STEP) satellite was launched on a Taurus booster from Vandenberg Air Force Base into a nearly circular, 105 degree inclined orbit on March 13, 1994. The purpose of this satellite is twofold: 1) to test a new concept in multiple procurements of fast-track modular satellites and 2) to test a suite of Air Force Phillips Laboratory payloads in space. The TAOS payloads include the Microcosm Autonomous N...

  14. Flight Simulator Evaluation of Display Media Devices for Synthetic Vision Concepts

    Science.gov (United States)

    Arthur, J. J., III; Williams, Steven P.; Prinzel, Lawrence J., III; Kramer, Lynda J.; Bailey, Randall E.

    2004-01-01

    The Synthetic Vision Systems (SVS) Project of the National Aeronautics and Space Administration's (NASA) Aviation Safety Program (AvSP) is striving to eliminate poor visibility as a causal factor in aircraft accidents as well as enhance operational capabilities of all aircraft. To accomplish these safety and capacity improvements, the SVS concept is designed to provide a clear view of the world around the aircraft through the display of computer-generated imagery derived from an onboard database of terrain, obstacle, and airport information. Display media devices with which to implement SVS technology that have been evaluated so far within the Project include fixed field of view head up displays and head down Primary Flight Displays with pilot-selectable field of view. A simulation experiment was conducted comparing these display devices to a fixed field of view, unlimited field of regard, full color Helmet-Mounted Display system. Subject pilots flew a visual circling maneuver in IMC at a terrain-challenged airport. The data collected for this experiment is compared to past SVS research studies.

  15. From conception to evaluation of mobile services for people with head injury: A participatory design perspective.

    Science.gov (United States)

    Groussard, Pierre-Yves; Pigot, Hélène; Giroux, Sylvain

    2015-12-17

    Adults with cognitive impairments lack the means to organise their daily life, plan their appointments, cope with fatigue, and manage their budget. They manifest interest in using new technologies to be part of society. Unfortunately, the applications offered on smart phones are often beyond their cognitive abilities. The goal of this study was to design a mobile cognitive assistant to enhance autonomy of people living with acquired traumatic brain injury. Participatory design methodologies guided this research by involving adults with cognitive impairments (CI) and their caregivers in the early stages of the design process. The population of the study is composed of four male adults who present cognitive impairments (three with head injury and one with stroke) and three caregivers. The first phase of this research was to design the Services Assistance Mobile and Intelligent (SAMI) application based on the needs expressed by the participants. During three focus groups, needs emerged concerning planning, health monitoring and money management and led to the implementation of assistive solutions on an Android mobile phone. During the second phase, the participants evaluated the mobile assistant SAMI at home for eight weeks. The results demonstrate that the participants were able to participate actively in the conception of SAMI and to use it successfully. People with CI showed a slight improvement in their life satisfaction. Due to the small number of participants, these promising results need to be confirmed by a larger-scale study.

  16. Evaluation of U-Zr hydride fuel for a thorium fuel cycle in an RTR concept

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kyung Taek; Cho, Nam Zin [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

    1998-12-31

    In this paper, we performed a design study of a thorium fueled reactor according to the design concept of the Radkowsky Thorium Reactor (RTR) and evaluated its overall performance. To enhance its performance and alleviate its problems, we introduced a new metallic uranium fuel, uranium-zirconium hydride (U-ZrH{sub 1.6}), as a seed fuel. For comparison, typical ABB/CE-type PWR based on SYSTEM 80+and standard RTR-type thorium reactor were also studied. From the results of performance analysis, we could ascertain advantages of RTR-type thorium fueled reactor in proliferation resistance, fuel cycle economics, and back-end fuel cycle. Also, we found that enhancement of proliferation resistance and safer operating conditions may be achieved by using the U-ZrH{sub 1.6} fuel in the seed region without additional penalties in comparison with the standard RTR`s U-Zr fuel. 6 refs., 2 figs., 6 tabs. (Author)

  17. Development of Concepts and Models of Performance Evaluation from the 19th Century to the Present

    Directory of Open Access Journals (Sweden)

    Hornungová Jana

    2014-07-01

    Full Text Available The main aim of this paper is to provide a framework of concepts and models from the area of performance measurement. Due to the fact that the business environment is con-stantly changing, changes also occur in the trends relating to performance. Traditional financial performance measures have been highly criticized and the need identified to integrate non-financial perspectives, such as level of innovation, degree of motivation, intellectual capital and other criteria. Intellectual capital is often a crucial factor in the creation of value in a company. This paper provides a literature review supplemented by the author’s research in the field of performance. The article shows that the performance appraisal system is currently focused on several areas that could affect the performance of the company, which is also part of the overall performance of the economy in the form of GDP growth. Based on the research, it can be said that, for the sample tracked, the selection of performance evaluation system does not depend on the legal form of the business.

  18. Evaluating High School Students' Conceptions of the Relationship between Mathematics and Physics: Development of a Questionnaire

    Science.gov (United States)

    Kapucu, S.; Öçal, M. F.; Simsek, M.

    2016-01-01

    The purposes of this study were (1) to develop a questionnaire measuring high school students' conceptions of the relationship between mathematics and physics, (2) and to determine the students' conceptions of the relationship between mathematics and physics. A total of 718 high school students (343 male, 375 female) participated in this study.…

  19. Communications satellites - The experimental years

    Science.gov (United States)

    Edelson, B. I.

    1983-10-01

    Only eight years after the launc of Sputnik-1 by the Soviet Union, the first commercial satellite, 'Early Bird', entered service. In just twelve years commercial satellite service extended around the earth and became profitable. The reasons for the successful development of the communications satellite services in a comparatively short time are considered. These reasons are related to the presence of three ingredients, taking into account technology to create the system, communications requirements to form a market, and a management structure to implement the system. The formation of the concept of using earth orbiting satellites for telecommunications is discussed. It is pointed out that the years from 1958 to 1964 were the true 'experimental years' for satellite communications. The rapid development of technology during this crucial period is described, giving attention to passive satellites, active systems, and development satellites.

  20. Multidimensional cognitive evaluation of patients with disorders of consciousness using EEG: A proof of concept study.

    Science.gov (United States)

    Sergent, Claire; Faugeras, Frédéric; Rohaut, Benjamin; Perrin, Fabien; Valente, Mélanie; Tallon-Baudry, Catherine; Cohen, Laurent; Naccache, Lionel

    2017-01-01

    sensitivity. The presence of a high-level effect in any of the three tested domains distinguished between minimally conscious and vegetative patients, while the presence of low-level effects was similar in both groups. In summary, this study constitutes a validated proof of concept in favor of probing multiple cognitive dimensions to improve the evaluation of non-communicating patients. At a more conceptual level, this EEG tool can help achieve a better understanding of disorders of consciousness by exploring consciousness in its multiple cognitive facets.

  1. Hydrothermal Treatment (HTT) of Microalgae: Evaluation of the Process As Conversion Method in an Algae Biorefinery Concept

    NARCIS (Netherlands)

    Garcia Alba, L.; Torri, C.; Samori, C.; Spek, van der J.J.; Fabbri, D.; Kersten, S.R.A.; Brilman, D.W.F.

    2012-01-01

    The hydrothermal treatment (HTT) technology is evaluated for its potential as a process to convert algae and algal debris into a liquid fuel, within a sustainable algae biorefinery concept in which, next to fuels (gaseous and liquid), high value products are coproduced, nutrients and water are recyc

  2. Hydrothermal Treatment (HTT) of Microalgae: Evaluation of the Process As Conversion Method in an Algae Biorefinery Concept

    NARCIS (Netherlands)

    Garcia Alba, Laura; Torri, C.; Samori, C.; van der Spek, J.J.; Fabbri, D.; Kersten, Sascha R.A.; Brilman, Derk Willem Frederik

    2012-01-01

    The hydrothermal treatment (HTT) technology is evaluated for its potential as a process to convert algae and algal debris into a liquid fuel, within a sustainable algae biorefinery concept in which, next to fuels (gaseous and liquid), high value products are coproduced, nutrients and water are

  3. Evaluations for service-sire conception rate for heifer and cow inseminations with conventional and sexed semen

    Science.gov (United States)

    Service-sire conception rate (SCR), a phenotypic fertility evaluation based on conventional (nonsexed) inseminations from parities 1 through 5, was implemented by USDA in August 2008. Using insemination data from 2005 through 2009, the SCR procedure was applied separately for nulliparous heifer inse...

  4. Evaluation of intra- and interspecific divergence of satellite DNA sequences by nucleotide frequency calculation and pairwise sequence comparison

    Directory of Open Access Journals (Sweden)

    Kato Mikio

    2003-01-01

    Full Text Available Satellite DNA sequences are known to be highly variable and to have been subjected to concerted evolution that homogenizes member sequences within species. We have analyzed the mode of evolution of satellite DNA sequences in four fishes from the genus Diplodus by calculating the nucleotide frequency of the sequence array and the phylogenetic distances between member sequences. Calculation of nucleotide frequency and pairwise sequence comparison enabled us to characterize the divergence among member sequences in this satellite DNA family. The results suggest that the evolutionary rate of satellite DNA in D. bellottii is about two-fold greater than the average of the other three fishes, and that the sequence homogenization event occurred in D. puntazzo more recently than in the others. The procedures described here are effective to characterize mode of evolution of satellite DNA.

  5. OMV With Satellite

    Science.gov (United States)

    1986-01-01

    This 1986 artist's concept shows the Orbital Maneuvering Vehicle (OMV) towing a satellite. As envisioned by Marshall Space Flight Center plarners, the OMV would be a remotely-controlled free-flying space tug which would place, rendezvous, dock, and retrieve orbital payloads.

  6. High Coverage Point to Point Transit (HCPPT): A New Design Concept and Simulation-Evaluation of Operational Schemes

    OpenAIRE

    2003-01-01

    This dissertation research proposes the development and evaluation of a new concept for high coverage point-to-point transit systems (HCPPT). Overall, three major contributions can be identified as the core of this research: the proposed scheme design, the development of sophisticated routing rules that can be updated in real-time to implement and optimize the operation of such a design, and the implementation of a multi-purpose simulation platform in order to simulate and evaluate such a des...

  7. Handbook of satellite applications

    CERN Document Server

    Madry, Scott; Camacho-Lara, Sergio

    2013-01-01

    Top space experts from around the world have collaborated to produce this comprehensive, authoritative, and clearly illustrated reference guide to the fast growing, multi-billion dollar field of satellite applications and space communications. This handbook, done under the auspices of the International Space University based in France, addresses not only system technologies but also examines market dynamics, technical standards and regulatory constraints. The handbook is a completely multi-disciplinary reference book that covers, in an in-depth fashion, the fields of satellite telecommunications, Earth observation, remote sensing, satellite navigation, geographical information systems, and geosynchronous meteorological systems. It covers current practices and designs as well as advanced concepts and future systems. It provides a comparative analysis of the common technologies and design elements for satellite application bus structures, thermal controls, power systems, stabilization techniques, telemetry, com...

  8. The FAO/NASA/NLR Artemis system - An integrated concept for environmental monitoring by satellite in support of food/feed security and desert locust surveillance

    Science.gov (United States)

    Hielkema, J. U.; Howard, J. A.; Tucker, C. J.; Van Ingen Schenau, H. A.

    1987-01-01

    The African real time environmental monitoring using imaging satellites (Artemis) system, which should monitor precipitation and vegetation conditions on a continental scale, is presented. The hardware and software characteristics of the system are illustrated and the Artemis databases are outlined. Plans for the system include the use of hourly digital Meteosat data and daily NOAA/AVHRR data to study environmental conditions. Planned mapping activities include monthly rainfall anomaly maps, normalized difference vegetation index maps for ten day and monthly periods with a spatial resolution of 7.6 km, ten day crop/rangeland moisture availability maps, and desert locust potential breeding activity factor maps for a plague prevention program.

  9. Evaluation of NOx emission inventories in California using multi-satellite data sets, in-situ airborne measurements, and regional model simulations during the CalNex 2010 field campaign

    Science.gov (United States)

    Kim, S.; Ahmadov, R.; Angevine, W. M.; Boersma, F. F.; Brioude, J.; Browne, E. C.; Bucsela, E. J.; Burrows, J. P.; Celarier, E. A.; Cohen, R. C.; Frost, G. J.; Krotkov, N. A.; Lamsal, L.; Lee, S.; Martin, R. V.; McKeen, S. A.; Pollack, I. B.; Richter, A.; Russell, A. R.; Ryerson, T. B.; Trainer, M.; Valin, L. C.

    2011-12-01

    Satellite NO2 column measurements indicate large NOx emissions from urban and agricultural sources in California. In this presentation, we highlight the NOx sources identified in California using the satellite measurements. Comparison of regional model-simulated NO2 columns with satellite retrievals has proven useful in evaluating emission inventories for various sectors. We compare the NO2 columns from the WRF-Chem model with the multi-satellite data sets from different instruments and retrieval groups for a variety of California sources. Use of multiple satellite data sets help to define the uncertainties in the satellite retrievals. In addition, the CalNex 2010 intensive field campaign provides a unique opportunity to independently assess California's emission inventories. The in-situ airborne observations from CalNex 2010 and fine-resolution model simulations are used to estimate the accuracy of the satellite NO2 column retrievals.

  10. Concept evaluation of a novel gear selector for automated manual transmissions

    Science.gov (United States)

    Zhong, Zaimin; Kong, Guoling; Yu, Zhuoping; Chen, Xinbo; Chen, Xueping; Xin, Xiangyan

    2012-08-01

    The existing Automatic Mechanical Transmission (AMT), whether electrically or hydraulically actuated, integrates shift actuators with gearbox shell as one unit by installing actuators on the gearbox. The problem it brings about is that the modification of the gearbox shell would be required, which increases the cost of AMT system. This paper proposes a novel gear selector for AMT, the concept of which enables the automation of shift action remotely realized by DC motors through shifting cable that originally used on manual transmission vehicle. Evidently, the advantage of this concept is that the automation of manual transmission could be easily realized by replacing the shift lever with two motors while the original shifting cable and gearbox could be reserved. Then the cost and development period can be shorten remarkably. Firstly, the concept of the novel gear selector is introduced, then the detailed mathematical model of shifting process is studied, and system design and scheme selection of this concept are performed. Optimal control algorithm based on LQR for actuator position feedback control is introduced. The concept and control algorithm are verified on a sample car, and considering the influence of the long path of transmission mechanism, the validation of the stability of this concept is performed through calibration test on mountain pass, and the obtained results show the concept of the novel gear selector for AMT is feasible technically with strong robust on the shifting stability, and it shows enormous potential for industrialization.

  11. Multidimensional cognitive evaluation of patients with disorders of consciousness using EEG: A proof of concept study

    Directory of Open Access Journals (Sweden)

    Claire Sergent

    2017-01-01

    In the present study we built a unique EEG protocol that probed 8 dimensions of cognitive processing in a single 1.5 h session. This protocol probed variants of classical markers together with new markers of spatial attention, which has not yet been studied in these patients. The eight dimensions were: (1 own name recognition, (2 temporal attention, (3 spatial attention, (4 detection of spatial incongruence (5 motor planning, and (6,7,8 modulations of these effects by the global context, reflecting higher-level functions. This protocol was tested in 15 healthy control subjects and in 17 patients with various etiologies, among which 13 could be included in the analysis. The results in the control group allowed a validation and a specific description of the cognitive levels probed by each marker. At the single-subject level, this combined protocol allowed assessing the presence of both classical and newly introduced markers for each patient and control, and revealed that the combination of several markers increased diagnostic sensitivity. The presence of a high-level effect in any of the three tested domains distinguished between minimally conscious and vegetative patients, while the presence of low-level effects was similar in both groups. In summary, this study constitutes a validated proof of concept in favor of probing multiple cognitive dimensions to improve the evaluation of non-communicating patients. At a more conceptual level, this EEG tool can help achieve a better understanding of disorders of consciousness by exploring consciousness in its multiple cognitive facets.

  12. Comparing the force and motion conceptual evaluation and the force concept inventory

    Directory of Open Access Journals (Sweden)

    Karen Cummings

    2009-03-01

    Full Text Available In this paper we compare and contrast student’s pretest/post-test performance on the Halloun-Hestenes force concept inventory (FCI to the Thornton-Sokoloff force and motion conceptual evaluation (FMCE. Both tests are multiple-choice assessment instruments whose results are used to characterize how well a first term, introductory physics course promotes conceptual understanding. However, the two exams have slightly different content domains, as well as different representational formats; hence, one exam or the other might better fit the interests of a given instructor or researcher. To begin the comparison, we outline how to determine a single-number score for the FMCE and present ranges of normalized gains on this exam. We then compare scores on the FCI and the FMCE for approximately 2000 students enrolled in the Studio Physics course at Rensselaer Polytechnic Institute over a period of eight years (1998–2006 that encompassed significant evolution of the course and many different instructors. We found that the mean score on the FCI is significantly higher than the mean score on the FMCE, however there is a very strong relationship between scores on the two exams. The slope of a best fit line drawn through FCI versus FMCE data is approximately 0.54, and the correlation coefficient is approximately r=0.78 , for preinstructional and postinstructional testings combined. In spite of this strong relationship, the assessments measure different normalized gains under identical circumstances. Additionally, students who scored well on one exam did not necessarily score well on the other. We use this discrepancy to uncover some subtle, but important, differences between the exams. We also present ranges of normalized gains for the FMCE in a variety of instructional settings.

  13. Comparing the force and motion conceptual evaluation and the force concept inventory

    Directory of Open Access Journals (Sweden)

    Ronald K Thornton

    2009-03-01

    Full Text Available In this paper we compare and contrast student’s pretest/post-test performance on the Halloun-Hestenes force concept inventory (FCI to the Thornton-Sokoloff force and motion conceptual evaluation (FMCE. Both tests are multiple-choice assessment instruments whose results are used to characterize how well a first term, introductory physics course promotes conceptual understanding. However, the two exams have slightly different content domains, as well as different representational formats; hence, one exam or the other might better fit the interests of a given instructor or researcher. To begin the comparison, we outline how to determine a single-number score for the FMCE and present ranges of normalized gains on this exam. We then compare scores on the FCI and the FMCE for approximately 2000 students enrolled in the Studio Physics course at Rensselaer Polytechnic Institute over a period of eight years (1998–2006 that encompassed significant evolution of the course and many different instructors. We found that the mean score on the FCI is significantly higher than the mean score on the FMCE, however there is a very strong relationship between scores on the two exams. The slope of a best fit line drawn through FCI versus FMCE data is approximately 0.54, and the correlation coefficient is approximately r=0.78, for preinstructional and postinstructional testings combined. In spite of this strong relationship, the assessments measure different normalized gains under identical circumstances. Additionally, students who scored well on one exam did not necessarily score well on the other. We use this discrepancy to uncover some subtle, but important, differences between the exams. We also present ranges of normalized gains for the FMCE in a variety of instructional settings.

  14. Evaluating the design of satellite scanning radiometers for earth radiation budget measurements with system simulations. Part 1: Instantaneous estimates

    Science.gov (United States)

    Stowe, Larry; Ardanuy, Philip; Hucek, Richard; Abel, Peter; Jacobowitz, Herbert

    1991-10-01

    A set of system simulations was performed to evaluate candidate scanner configurations to fly as a part of the Earth Radiation Budget Instrument (ERBI) on the polar platforms during the 1990's. The simulation is considered of instantaneous sampling (without diurnal averaging) of the longwave and shortwave fluxes at the top of the atmosphere (TOA). After measurement and subsequent inversion to the TOA, the measured fluxes were compared to the reference fluxes for 2.5 deg lat/long resolution targets. The reference fluxes at this resolution are obtained by integrating over the 25 x 25 = 625 grid elements in each target. The differences between each of these two resultant spatially averaged sets of target measurements (errors) are taken and then statistically summarized. Five instruments are considered: (1) the Conically Scanning Radiometer (CSR); (2) the ERBE Cross Track Scanner; (3) the Nimbus-7 Biaxial Scanner; (4) the Clouds and Earth's Radiant Energy System Instrument (CERES-1); and (5) the Active Cavity Array (ACA). Identical studies of instantaneous error were completed for many days, two seasons, and several satellite equator crossing longitudes. The longwave flux errors were found to have the same space and time characteristics as for the shortwave fluxes, but the errors are only about 25 pct. of the shortwave errors.

  15. Evaluation and modeling of autonomous attitude thrust control for the Geostation Operational Environmental Satellite (GOES)-8 orbit determination

    Science.gov (United States)

    Forcey, W.; Minnie, C. R.; Defazio, R. L.

    1995-01-01

    The Geostationary Operational Environmental Satellite (GOES)-8 experienced a series of orbital perturbations from autonomous attitude control thrusting before perigee raising maneuvers. These perturbations influenced differential correction orbital state solutions determined by the Goddard Space Flight Center (GSFC) Goddard Trajectory Determination System (GTDS). The maneuvers induced significant variations in the converged state vector for solutions using increasingly longer tracking data spans. These solutions were used for planning perigee maneuvers as well as initial estimates for orbit solutions used to evaluate the effectiveness of the perigee raising maneuvers. This paper discusses models for the incorporation of attitude thrust effects into the orbit determination process. Results from definitive attitude solutions are modeled as impulsive thrusts in orbit determination solutions created for GOES-8 mission support. Due to the attitude orientation of GOES-8, analysis results are presented that attempt to absorb the effects of attitude thrusting by including a solution for the coefficient of reflectivity, C(R). Models to represent the attitude maneuvers are tested against orbit determination solutions generated during real-time support of the GOES-8 mission. The modeling techniques discussed in this investigation offer benefits to the remaining missions in the GOES NEXT series. Similar missions with large autonomous attitude control thrusting, such as the Solar and Heliospheric Observatory (SOHO) spacecraft and the INTELSAT series, may also benefit from these results.

  16. Evaluation of Satellite-based Global Hydrologic Simulation using the Distributed CREST Model and Global Runoff Data Centre Archives

    Science.gov (United States)

    Xue, X.; Hong, Y.; Gourley, J. J.; Wang, X.

    2011-12-01

    Flooding is one of the most deadly natural hazards around the world. Distributed hydrologic models can provide the spatial and temporal distribution of precipitation, soil moisture, evapotranspiration and runoff. Implementation of a flood prediction and/or forecast system using a distributed hydrologic model can potentially help mitigate flood-induced hazards. In this study, we propose the use of the Coupled Routing and Excess STorage (CREST) distributed hydrological model driven by real-time rainfall forcing from TRMM-based multi-satellite products and/or precipitation forecast data from the Global Forecast System model (GFS), combined with automatic parameter optimization methods, to estimate hydrological fluxes, storages and inundated areas. Evaluations show that: 1) the capability of real-time streamflow prediction and/or forecast at drainage outlets and identification of inundated areas upstream is an achievable goal even for ungauged basins; 2) a-priori, physically-based parameter estimates with CREST reduce the dependence on rainfall-runoff data often required to calibrate distributed hydrologic models; and 3) the validation of CREST simulations of basin discharge are skillful in several basins throughout the world.

  17. Using records from submarine, aircraft and satellite to evaluate climate model simulations of Arctic sea ice thickness

    Directory of Open Access Journals (Sweden)

    J. Stroeve

    2014-04-01

    Full Text Available Arctic sea ice thickness distributions from models participating in the World Climate Research Programme Coupled Model Intercomparison Project Phase 5 are evaluated against observations from submarines, aircraft and satellites. While it's encouraging that the mean thickness distributions from the models are in general agreement with observations, the spatial patterns of sea ice thickness are poorly represented in most models. The poor spatial representation of thickness patterns is associated with a failure of models to represent details of the mean atmospheric circulation pattern that governs the transport and spatial distribution of sea ice. The climate models as a whole also tend to underestimate the rate of ice volume loss from 1979 to 2013, though the multi-model ensemble mean trend remains within the uncertainty of that from the Pan-Arctic Ice Ocean Modeling and Assimilation System. These results raise concerns regarding the ability of CMIP5 models to realistically represent the processes driving the decline of Arctic sea ice and project the timing of when a seasonally ice-free Arctic may be realized.

  18. Conception d'une methodologie generale d'evaluation de la traduction automatique (Conception of a General Methodology for Evaluating Machine Translation).

    Science.gov (United States)

    van Slype, Georges

    1982-01-01

    It is proposed that assessment of human translation versus machine translation programs use methods and criteria that measure efficiency and cost effectiveness and are efficient and cost-effective in themselves. A variety of methods and criteria are evaluated and discussed. (MSE)

  19. Development of space manufacturing systems concepts utilizing lunar resources

    Science.gov (United States)

    Bock, E. H.

    1979-01-01

    Results of a NASA sponsored study to evaluate the merits of constructing solar power satellites using lunar and terrestrial resources are reviewed. Three representative lunar resources utilization (LRU) concepts were developed and compared with a previously designed earth baseline concept, and major system hardware elements as well as personnel requirements were defined. LRU for space construction was shown to be competitive with earth baseline approach for a program requiring 10 to the 5th metric tons per year of completed satellites. Results also indicated that LRU can reduce earth launched cargo requirements to less than 10% of that needed to build satellites exclusively from earth materials, with a significant percentage of the reduction due to the use of liquid oxygen derived from lunar soil. A concept using the mass driver to catapult lunar material into space was found to be superior to the other LRU logistics techniques investigated.

  20. Academic Achievement in College: the Predictive Value of Subjective Evaluations of Intelligence and Academic Self-concept

    Directory of Open Access Journals (Sweden)

    Tatiana V. Kornilova

    2009-01-01

    Full Text Available The study examined the relationship between self-, peer- and test-estimated intelligence, academic self-concept and academic achievement. Subjective evaluations of intelligence and academic self-concept had incremental predictive value over conventional intelligence when predicting achievement accounting for more than 40% of its variance. The obtained pattern of results is presented via SEM-model which accounts for 75% variance in the latent factor of academic achievement. Author suggests the importance of further studying complex sets of achievement predictors from ability, personality and mediating domains.

  1. Concept - or no concept

    DEFF Research Database (Denmark)

    Thorsteinsson, Uffe

    1999-01-01

    Discussion about concept in industrial companies. A method for mapping of managerial concept in specific area is shown......Discussion about concept in industrial companies. A method for mapping of managerial concept in specific area is shown...

  2. US EPA BIOMONITORING AND BIOINDICATOR CONCEPTS NEEDED TO EVALUATE THE BIOLOGICAL INTEGRITY OF AQUATIC SYSTEMS

    Science.gov (United States)

    This chapter presents the current uses, concepts and anticipated future directions of biomonitoring and bioindicators in the regulatory and research programs of the United States Environmental Protection Agency (USEPA). The chapter provides a historical look on how biomonitoring ...

  3. USEPA BIOMONITORING AND BIOINDICATORS CONCEPTS NEEDED TO EVALUATE THE BIOLOGICAL INTEGRITY OF AQUATIC SYSTEMS

    Science.gov (United States)

    This chapter presents the current uses, concepts and anticipated future directions of biomonitoring and bioindicators in the regulatory and research programs of the United States Environmental Protection Agency (USEPA). The chapter provides a historical look on how biomonitoring ...

  4. Analyzing Classroom Strategy: Evaluating the Concept Mapping Technique at SSC Level in Pakistan

    Directory of Open Access Journals (Sweden)

    Sidra Mahmood

    2015-08-01

    Full Text Available This study documents the usage of Concept Mapping in the teaching-learning situation of English at SSC Level. The study is descriptive and analytical in nature and tries to investigate the effects which Concept Mapping renders in the academic environment in the context of ESL classroom setting. The research offers strategies for adopting certain techniques and up gradation of the content taught at the mentioned level by the inculcation of such techniques. Overall, the study produced a range of implementable outcomes by a pervasive discussion of Concept Mapping, the role of the textbooks, the importance of adding the technique to the contents of ESL classroom setting. For data collection and data analysis, two classes were selected. Both were taught the same content under controlled conditions. The concept mapping technique in the class guided the learners towards the improved way of learning the text of second language.

  5. Evaluation of the Bird Conservation Area Concept in the Northern Tallgrass Prairie : Annual Report: 1999

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In 1998 we initiated a test of the concept that Bird Conservation Areas (BCA's) can maintain populations of breeding grassland birds. The underlying hypothesis is...

  6. Evaluation by Concept Map and its Rubric%概念地图评价及量规

    Institute of Scientific and Technical Information of China (English)

    陈春生; 谢常

    2012-01-01

    A concept map is a visual representation of an knowledge structure constructed by an individual on a particular topic, and it's a visual semantic network about the knowledge components in a particular field organized in a pattern based on the internal relationship. A concept map can be used to perform placement evaluation, formative evaluation, diagnostic evaluation and summative evaluation. Concept maps are indicating the evaluation methods shifting from traditional ones to modern and they are enjoying its popularity nowadays. This paper introduces the ways of evaluation by concept map, and elaborates on its rubric.%概念地图是个体对特定主题建构的知识结构的视觉化表征,是人们将某一领域内的知识元素按其内在关联建立起来的一种可视化语义网络。概念地图可用作定位性评价、形成性评价、诊断性评价和总结性评价。概念地图作为一个从传统学生评价向现代学生评价转化的很好的评价工具,越来越受到大家的重视。本文介绍了概念地图评价实施方法,并详细阐释了概念地图的量规。

  7. Inter-Satellite Comparison and Evaluation of Navy SNPP-VIIRS and MODIS-Aqua Ocean Color Properties

    Science.gov (United States)

    2014-07-01

    DATE (DD-MM-YYYYJ 31-07-2014 REPORT TYPE Conference Proceeding 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE Inter-Satellite Comparison...ocean color retrievals^’ "■. MODIS has reached its end-of-life expectancy and VIIRS continues to have issues with degradation in radiometric calibration...Clark, D., "The marine optical buoy (MOBY) radiometric calibration and uncertainty budget for ocean color satellite sensor vicarious calibration

  8. Use of A-train satellite observations (CALIPSO-PARASOL) to evaluate tropical cloud properties in the LMDZ5 GCM

    Science.gov (United States)

    Konsta, D.; Dufresne, J.-L.; Chepfer, H.; Idelkadi, A.; Cesana, G.

    2016-08-01

    The evaluation of key cloud properties such as cloud cover, vertical profile and optical depth as well as the analysis of their intercorrelation lead to greater confidence in climate change projections. In addition, the comparison between observations and parameterizations of clouds in climate models is improved by using collocated and instantaneous data of cloud properties. Simultaneous and independent observations of the cloud cover and its three-dimensional structure at high spatial and temporal resolutions are made possible by the new space-borne multi-instruments observations collected with the A-train. The cloud cover and its vertical structure observed by CALIPSO and the visible directional reflectance (a surrogate for the cloud optical depth) observed by PARASOL, are used to evaluate the representation of cloudiness in two versions of the atmospheric component of the IPSL-CM5 climate model (LMDZ5). A model-to-satellite approach, applying the CFMIP Observation Simulation Package (COSP), is used to allow a quantitative comparison between model results and observations. The representation of clouds in the two model versions is first evaluated using monthly mean data. This classical approach reveals biases of different magnitudes in the two model versions. These biases consist of (1) an underestimation of cloud cover associated to an overestimation of cloud optical depth, (2) an underestimation of low- and mid-level tropical clouds and (3) an overestimation of high clouds. The difference in the magnitude of these biases between the two model versions clearly highlights the improvement of the amount of boundary layer clouds, the improvement of the properties of high-level clouds, and the improvement of the simulated mid-level clouds in the tropics in LMDZ5B compared to LMDZ5A, due to the new convective, boundary layer, and cloud parametrizations implemented in LMDZ5B. The correlation between instantaneous cloud properties allows for a process-oriented evaluation

  9. Evaluation of Various Retrofitting Concepts of Building Envelope for Offices Equipped with Large Radiant Ceiling Panels by Dynamic Simulations

    Directory of Open Access Journals (Sweden)

    Sabina Jordan

    2015-09-01

    Full Text Available In order to achieve significant savings in energy and an improved level of thermal comfort in retrofitted existing buildings, specific retrofitting concepts that combine new technologies and design need to be developed and implemented. Large radiant surfaces systems are now among the most promising future technologies to be used both in retrofitted and in new low-energy buildings. These kinds of systems have been the topic of several studies dealing with thermal comfort and energy utilization, but some specific issues concerning their possible use in various concepts for retrofitting are still poorly understood. In the present paper, some results of dynamic simulations, with the transient system simulation tool (TRNSYS model, of the retrofitted offices equipped with radiant ceiling panels are presented and thoroughly analysed. Based on a precise comparison of the results of these simulations with actual measurements in the offices, certain input data for the model were added, so that the model was consequently validated. The model was then applied to the evaluation of various concepts of building envelopes for office retrofitting. By means of dynamic simulations of indoor environment it was possible to determine the benefits and limitations of individual retrofitting concepts. Some specific parameters, which are relevant to these concepts, were also identified.

  10. Development and evaluation of a thermochemistry concept inventory for college-level general chemistry

    Science.gov (United States)

    Wren, David A.

    The research presented in this dissertation culminated in a 10-item Thermochemistry Concept Inventory (TCI). The development of the TCI can be divided into two main phases: qualitative studies and quantitative studies. Both phases focused on the primary stakeholders of the TCI, college-level general chemistry instructors and students. Each phase was designed to collect evidence for the validity of the interpretations and uses of TCI testing data. A central use of TCI testing data is to identify student conceptual misunderstandings, which are represented as incorrect options of multiple-choice TCI items. Therefore, quantitative and qualitative studies focused heavily on collecting evidence at the item-level, where important interpretations may be made by TCI users. Qualitative studies included student interviews (N = 28) and online expert surveys (N = 30). Think-aloud student interviews (N = 12) were used to identify conceptual misunderstandings used by students. Novice response process validity interviews (N = 16) helped provide information on how students interpreted and answered TCI items and were the basis of item revisions. Practicing general chemistry instructors (N = 18), or experts, defined boundaries of thermochemistry content included on the TCI. Once TCI items were in the later stages of development, an online version of the TCI was used in expert response process validity survey (N = 12), to provide expert feedback on item content, format and consensus of the correct answer for each item. Quantitative studies included three phases: beta testing of TCI items (N = 280), pilot testing of the a 12-item TCI (N = 485), and a large data collection using a 10-item TCI ( N = 1331). In addition to traditional classical test theory analysis, Rasch model analysis was also used for evaluation of testing data at the test and item level. The TCI was administered in both formative assessment (beta and pilot testing) and summative assessment (large data collection), with

  11. Evaluation of Process Capability in Gas Carburizing Process to Achieve Quality through Limit Design Concept

    Institute of Scientific and Technical Information of China (English)

    K. Palaniradja; N. Alagumurthi; V. Soundararajan

    2004-01-01

    Steel is the most important metallic material used in industry. This is because of the versatility of its engineering properties under different conditions. In one condition it can be very mild, soft and suitable for any forming operation. In another condition the same steel can be very hard and strong. This versatility is made possible by the different heat treatments that the steel can be subject to. One such treatment is Gas carburizing. This is the most widely used process for surface hardening of low carbon steels. In this method the surface composition of the steel changes by diffusion of carbon and or nitrogen and result in hard outer surface with good wear resistance properties. A striking feature of Gas Carburizing process is that in this process the original toughness and ductility remains unaffected even after heat treatment. 3% nickel chromium case hardened low carbon steels are widely used for critical automotive and machine applications such as rack and pinion, gears, camshaft, valve rocker shafts and axles which requires high fatigue resistance. Fatigue behaviour of case carburized parts depends to a great extent on the correct combination of Hardness Penetration Depth (HPD) and the magnitude of hardness at the surface and beneath the surface with low size and shape distortion. In order to reduce the manufacturing costs in terms of material consumption and elimination of the number of processing steps, the effect of Gas carburizing parameters on the fatigue behaviour should already be considered in the parameter design stage. Therefore it is of importance to optimize the gas carburizing process variables to attain quality products with respect to hardness and case depth. In the present paper, the evaluation of process capability was carried out through a Limit Design Concept called orthogonal array design of experiment. To optimize the process variables the influence of several parameters (Holding time,Carbon potential, Furnace temperature and Quench

  12. Evaluation of direct membrane filtration and direct forward osmosis as concepts for compact and energy-positive municipal wastewater treatment.

    Science.gov (United States)

    Hey, Tobias; Bajraktari, Niada; Davidsson, Åsa; Vogel, Jörg; Madsen, Henrik Tækker; Hélix-Nielsen, Claus; Jansen, Jes la Cour; Jönsson, Karin

    2017-02-22

    Municipal wastewater treatment commonly involves mechanical, biological and chemical treatment steps to protect humans and the environment from adverse effects. Membrane technology has gained increasing attention as an alternative to conventional wastewater treatment due to increased urbanization. Among the available membrane technologies, microfiltration and forward osmosis have been selected for this study due to their specific characteristics, such as compactness and efficient removal of particles. In this study, two treatment concepts were evaluated with regard to their specific electricity, energy and area demands. Both concepts would fulfil the Swedish discharge demands for small and medium-sized wastewater treatment plants at full scale: 1) direct microfiltration and 2) direct forward osmosis with seawater as the draw solution. The framework of this study is based on a combination of data obtained from bench- and pilot-scale experiments applying direct microfiltration and forward osmosis, respectively. Additionally, available complementary data from a Swedish full-scale wastewater treatment plant and the literature were used to evaluate the concepts in depth. The results of this study indicate that both concepts are net positive with respect to electricity and energy, as more biogas can be produced compared to conventional wastewater treatment. Furthermore, the specific area demand is significantly reduced. This study demonstrates that municipal wastewater could be treated in a more energy- and area-efficient manner with techniques that are already commercially available and with future membrane technology.

  13. Analysis and Critical Evaluation of Xu Fuguan’s Interpretation of the Concept qiyun shengdong 气韵生动

    Directory of Open Access Journals (Sweden)

    Téa SERNELJ

    2017-06-01

    Full Text Available The present article deals with Xu Fuguan’s analysis and interpretation of qiyun shengdong, which is regarded as one of the most significant and fundamental, as well as complex, concepts in Chinese aesthetics. It was developed in the Wei Jin period (220–420 AD, which is considered the turning point in Chinese aesthetics and art. Its complexity is expressed in literary works, painting, calligraphy and music, as well as in literary and painting theory. In Xu’s interpretation, the concept of qi refers to the outward characteristics of the art work. The concept yun reflects the inner characteristics that are an integral part of the human spirit, while shengdong is merely a spontaneous and natural effect of the interaction between qi and yun. First, the author presents Xu Fuguan’s interpretation and places it in the context of contemporary debates on Chinese aesthetics. The author then concentrates on Xu Fuguan’s philological and historical analysis of the semantic and philosophical development of the concept, and at the end gives a critical evaluation of his study in the context of the re-evaluation of the basics of classical Chinese aesthetics.

  14. Varying applicability of four different satellite-derived soil moisture products to global gridded crop model evaluation

    Science.gov (United States)

    Sakai, Toru; Iizumi, Toshichika; Okada, Masashi; Nishimori, Motoki; Grünwald, Thomas; Prueger, John; Cescatti, Alessandro; Korres, Wolfgang; Schmidt, Marius; Carrara, Arnaud; Loubet, Benjamin; Ceschia, Eric

    2016-06-01

    Satellite-derived daily surface soil moisture products have been increasingly available, but their applicability to global gridded crop model (GGCM) evaluation is unclear. This study compares four different soil moisture products with the flux tower site observation at 18 cropland sites across the world where either of maize, soybean, rice and wheat is grown. These products include the first and second versions of Climate Change Initiative Soil Moisture (CCISM-1 and CCISM-2) datasets distributed by the European Space Agency and two different AMSR-E (Advanced Microwave Scanning Radiometer-Earth Observing System)-derived soil moisture datasets, separately provided by the Japan Aerospace Exploration Agency (AMSRE-J) and U.S. National Aeronautics and Space Administration (AMSRE-N). The comparison demonstrates varying reliability of these products in representing major characteristics of temporal pattern of cropland soil moisture by product and crop. Possible reasons for the varying reliability include the differences in sensors, algorithms, bands and criteria used when estimating soil moisture. Both the CCISM-1 and CCISM-2 products appear the most reliable for soybean- and wheat-growing area. However, the percentage of valid data of these products is always lower than other products due to relatively strict criteria when merging data derived from multiple sources, although the CCISM-2 product has much more data with valid retrievals than the CCISM-1 product. The reliability of the AMSRE-J product is the highest for maize- and rice-growing areas and comparable to or slightly lower than the CCISM products for soybean- and wheat-growing areas. The AMSRE-N is the least reliable in most location-crop combinations. The reliability of the products for rice-growing area is far lower than that of other upland crops likely due to the extensive use of irrigation and patch distribution of rice paddy in the area examined here. We conclude that the CCISM-1, CCISM-2 and AMSRE

  15. [Software CMAP TOOLS ™ to build concept maps: an evaluation by nursing students].

    Science.gov (United States)

    Ferreira, Paula Barreto; Cohrs, Cibelli Rizzo; De Domenico, Edvane Birelo Lopes

    2012-08-01

    Concept mapping (CM) is a teaching strategy that can be used to solve clinical cases, but the maps are difficult to write. The objective of this study was to describe the challenges and contributions of the Cmap Tools® software in building concept maps to solve clinical cases. To do this, a descriptive and qualitative method was used with junior nursing students from the Federal University of São Paulo. The teaching strategy was applied and the data were collected using the focal group technique. The results showed that the software facilitates and guarantees the organization, visualization, and correlation of the data, but there are difficulties related to the handling of its tools initially. In conclusion, the formatting and auto formatting resources of Cmap Tools® facilitated the construction of concept maps; however, orientation strategies should be implemented for the initial stage of the software utilization.

  16. Vicarious Calibration Based Cross Calibration of Solar Reflective Channels of Radiometers Onboard Remote Sensing Satellite and Evaluation of Cross Calibration Accuracy through Band-to-Band Data Comparisons

    Directory of Open Access Journals (Sweden)

    Kohei Arai

    2013-04-01

    Full Text Available Accuracy evaluation of cross calibration through band-to-band data comparison for visible and near infrared radiometers which onboard earth observation satellites is conducted. The conventional cross calibration for visible to near infrared radiometers onboard earth observation satellites is conducted through comparisons of band-to-band data of which spectral response functions are overlapped mostly. There are the following major error sources due to observation time difference, spectral response function difference in conjunction of surface reflectance and atmospheric optical depth, observation area difference. These error sources are assessed with dataset acquired through ground measurements of surface reflectance and optical depth. Then the accuracy of the conventional cross calibration is evaluated with vicarious calibration data. The results show that cross calibration accuracy can be done more precisely if the influences due to the aforementioned three major error sources are taken into account.

  17. Satellite RNAs and Satellite Viruses.

    Science.gov (United States)

    Palukaitis, Peter

    2016-03-01

    Satellite RNAs and satellite viruses are extraviral components that can affect either the pathogenicity, the accumulation, or both of their associated viruses while themselves being dependent on the associated viruses as helper viruses for their infection. Most of these satellite RNAs are noncoding RNAs, and in many cases, have been shown to alter the interaction of their helper viruses with their hosts. In only a few cases have the functions of these satellite RNAs in such interactions been studied in detail. In particular, work on the satellite RNAs of Cucumber mosaic virus and Turnip crinkle virus have provided novel insights into RNAs functioning as noncoding RNAs. These effects are described and potential roles for satellite RNAs in the processes involved in symptom intensification or attenuation are discussed. In most cases, models describing these roles involve some aspect of RNA silencing or its suppression, either directly or indirectly involving the particular satellite RNA.

  18. Global budget of tropospheric ozone: Evaluating recent model advances with satellite (OMI), aircraft (IAGOS), and ozonesonde observations

    Science.gov (United States)

    Hu, Lu; Jacob, Daniel J.; Liu, Xiong; Zhang, Yi; Zhang, Lin; Kim, Patrick S.; Sulprizio, Melissa P.; Yantosca, Robert M.

    2017-10-01

    The global budget of tropospheric ozone is governed by a complicated ensemble of coupled chemical and dynamical processes. Simulation of tropospheric ozone has been a major focus of the GEOS-Chem chemical transport model (CTM) over the past 20 years, and many developments over the years have affected the model representation of the ozone budget. Here we conduct a comprehensive evaluation of the standard version of GEOS-Chem (v10-01) with ozone observations from ozonesondes, the OMI satellite instrument, and MOZAIC-IAGOS commercial aircraft for 2012-2013. Global validation of the OMI 700-400 hPa data with ozonesondes shows that OMI maintained persistent high quality and no significant drift over the 2006-2013 period. GEOS-Chem shows no significant seasonal or latitudinal bias relative to OMI and strong correlations in all seasons on the 2° × 2.5° horizontal scale (r = 0.88-0.95), improving on previous model versions. The most pronounced model bias revealed by ozonesondes and MOZAIC-IAGOS is at high northern latitudes in winter-spring where the model is 10-20 ppbv too low. This appears to be due to insufficient stratosphere-troposphere exchange (STE). Model updates to lightning NOx, Asian anthropogenic emissions, bromine chemistry, isoprene chemistry, and meteorological fields over the past decade have overall led to gradual increase in the simulated global tropospheric ozone burden and more active ozone production and loss. From simulations with different versions of GEOS meteorological fields we find that tropospheric ozone in GEOS-Chem v10-01 has a global production rate of 4960-5530 Tg a-1, lifetime of 20.9-24.2 days, burden of 345-357 Tg, and STE of 325-492 Tg a-1. Change in the intensity of tropical deep convection between these different meteorological fields is a major factor driving differences in the ozone budget.

  19. Evaluating the Force Concept Inventory for different student groups at the Norwegian University of Science and Technology

    CERN Document Server

    Persson, J R

    2015-01-01

    The Force Concept Inventory (FCI) was developed by Hestenes, Wells and Swackhamer, in order to assess student understanding of the concept of force. FCI has been used for over 20 years and in different countries. When applying the inventory in a new context it is important to evaluate the reliability and discrimination power of this assessment tool. In this study the reliability and discrimination power are evaluated in the context of Engineering education at a Norwegian university, using statistical tests, focusing on both item analysis and on the entire test. The results indicate that FCI is a reliable and discriminating tool in most cases. As there are exceptions, statistical tests should always be done when FCI is administered in a new context.

  20. Transmission Technique towards Seamless Handover for NGEO Satellite Networks

    Institute of Scientific and Technical Information of China (English)

    Wang LU; Liu Lixiang; Hu Xiaohui

    2011-01-01

    This paper presents a seamless transmission technique for Non-Geostationary Earth Orbit (NGEO) satellite networks.The seamless transmission technique combines the concept of Hop-by-Hop and network coding to alleviate the negative impacts of handovers,high bit error rate,and long delay,and to achieve high throughput and complete delivery in NGEO satellite networks.This network coding algorithm is able to maintain expected small queue size and low decoding latency.Furthermore,the seamless transmission technique applies a novel explicit congestion notification mechanism and can achieve high bandwidth utilization.Various aspects of this seamless transmission technique are evaluated.

  1. Conception et evaluation d'une intervention didactique a propos des phases de la lune dans un planetarium numerique

    Science.gov (United States)

    Chastenay, Pierre

    research (didactic engineering) aimed at improving it, both theoretically and practically, through multiple iterations in its "natural" environment, in this case an inflatable digital planetarium six metres in diameter. We are presenting the results of our first iteration, completed with help from six children aged 12 to 14 (four boys and two girls) whose conceptions about the lunar phases were noted before, during and after the intervention through group interviews, questionnaires, group exercises and recordings of the interventions throughout the activity. The evaluation was essentially qualitative, based on the traces obtained throughout the session, in particular within the planetarium itself. This material was then analyzed to validate the theoretical concepts that led to the conception of the teaching intervention and also to reveal possible ways to improve the intervention. We noted that the intervention indeed changed most participants' conceptions about the lunar phases, but also identified ways to boost its effectiveness in the future.

  2. Hypothesis Generation, Evaluation, and Memory Abilities in Adult Human Concept Learning.

    Science.gov (United States)

    Cason, Carolyn L.; And Others

    Studies were made between performance on tests of mental abilities and concept learning tasks; it is pointed out that the researcher is usually confronted with administering large batteries of tests of mental abilities and then analyzing his results with one of the factor analytic techniques. An information process analysis of tests of mental…

  3. Application Biosphere Compatibility Concept To Evaluate The Quality Of Urban Environment By Bioindication Methods

    Science.gov (United States)

    Vorobyov, S.

    2017-01-01

    This article focuses on the application of methods biondisation different types of urban green areas to assess the quality of urban environment from the standpoint of compatibility biosphere concept. To assess urban environmental quality, we used a variety of areas of the city of Orel with different levels of human impact.

  4. Intercultural Competence: Concepts, Challenges, Evaluations. Intercultural Studies and Foreign Language Learning. Volume 10

    Science.gov (United States)

    Witte, Arnd, Ed.; Harden, Theo, Ed.

    2011-01-01

    This book explores the idea of "intercultural competence", which, despite its current popularity across various discourses, has remained a vague and oscillating concept. Interculture lacks a universal definition and "competence" is not only a cognitive construct but also includes psychological traits such as attitudes, affective aspects and…

  5. Parenting Styles, Young Adults' Self-Concepts, and Evaluations of Parents.

    Science.gov (United States)

    Parish, Thomas S.; McCluskey, James J.

    1993-01-01

    Research shows that parenting style may strongly influence children's and adolescents' development. The present study reexamined this association, using a sample of 123 midwestern college students enrolled in a human development class. Participants' self-concepts varied directly with the perceived level of warmth displayed by both their fathers…

  6. Satellite power system (SPS) public outreach experiment

    Energy Technology Data Exchange (ETDEWEB)

    McNeal, S.R.

    1980-12-01

    To improve the results of the Satellite Power System (SPS) Concept Development and Evaluation Program, an outreach experiment was conducted. Three public interest groups participated: the L-5 Society (L-5), Citizen's Energy Project (CEP), and the Forum for the Advancement of Students in Science and Technology (FASST). Each group disseminated summary information about SPS to approximately 3000 constituents with a request for feedback on the SPS concept. The objectives of the outreach were to (1) determine the areas of major concern relative to the SPS concept, and (2) gain experience with an outreach process for use in future public involvement. Due to the combined efforts of all three groups, 9200 individuals/organizations received information about the SPS concept. Over 1500 receipients of this information provided feedback. The response to the outreach effort was positive for all three groups, suggesting that the effort extended by the SPS Project Division to encourage an information exchange with the public was well received. The general response to the SPS differed with each group. The L-5 position is very much in favor of SPS; CEP is very much opposed and FASST is relatively neutral. The responses are analyzed, and from the responses some questions and answers about the satellite power system are presented in the appendix. (WHK)

  7. Centriolar satellites

    DEFF Research Database (Denmark)

    Tollenaere, Maxim A X; Mailand, Niels; Bekker-Jensen, Simon

    2015-01-01

    Centriolar satellites are small, microscopically visible granules that cluster around centrosomes. These structures, which contain numerous proteins directly involved in centrosome maintenance, ciliogenesis, and neurogenesis, have traditionally been viewed as vehicles for protein trafficking...... highlight newly discovered regulatory mechanisms targeting centriolar satellites and their functional status, and we discuss how defects in centriolar satellite components are intimately linked to a wide spectrum of human diseases....

  8. Satellite theory

    Science.gov (United States)

    Kozai, Y.

    1981-04-01

    The dynamical characteristics of the natural satellite of Mars, Jupiter, Saturn, Uranus and Neptune are analyzed on the basis of the solar tidal perturbation factor and the oblateness factor of the primary planet for each satellite. For the inner satellites, for which the value of the solar tidal factor is much smaller than the planetary oblateness factor, it is shown that the eccentricity and inclination of satellite orbits are generally very small and almost constant; several pairs of inner satellites are also found to exhibit commensurable mean motions, or secular accelerations in mean longitude. In the case of the outer satellites, for which solar perturbations are dominant, secular perturbations and long-period perturbations may be derived by the solution of equations of motion reduced to one degree of freedom. The existence of a few satellites, termed intermediary satellites, for which the solar tidal perturbation is on the order of the planetary oblateness factor, is also observed, and the pole of the orbital plane of the satellite is noted to execute a complex motion around the pole of the planet or the orbital plane of the planet.

  9. Evaluation and intercomparison of clouds, precipitation, and radiation budgets in recent reanalyses using satellite-surface observations

    Science.gov (United States)

    Dolinar, Erica K.; Dong, Xiquan; Xi, Baike

    2016-04-01

    Atmospheric reanalysis datasets offer a resource for investigating climate processes and extreme events; however, their uncertainties must first be addressed. In this study, we evaluate the five reanalyzed (20CR, CFSR, Era-Interim, JRA-25, and MERRA) cloud fraction (CF), precipitation rates (PR), and top-of-atmosphere (TOA) and surface radiation budgets using satellite observations during the period 03/2000-02/2012. Compared to the annual averaged CF of 56.7 % from CERES MODIS (CM) four of the five reanalyses underpredict CFs by 1.7-4.6 %, while 20CR overpredicts this result by 7.4 %. PR from the Tropical Rainfall Measurement Mission (TRMM) is 3.0 mm/day and the reanalyzed PRs agree with TRMM within 0.1-0.6 mm/day. The shortwave (SW) and longwave (LW) TOA cloud radiative effects (CREtoa) calculated by CERES EBAF (CE) are -48.1 and 27.3 W/m2, respectively, indicating a net cooling effect of -20.8 W/m2. Of the available reanalysis results, the CFSR and MERRA calculated net CREtoa values agree with CE within 1 W/m2, while the JRA-25 result is ~10 W/m2 more negative than the CE result, predominantly due to the underpredicted magnitude of the LW warming in the JRA-25 reanalysis. A regime metric is developed using the vertical motion field at 500 hPa over the oceans. Aptly named the "ascent" and "descent" regimes, these areas are distinguishable in their characteristic synoptic patterns and the predominant cloud-types; convective-type clouds and marine boundary layer (MBL) stratocumulus clouds. In general, clouds are overpredicted (underpredicted) in the ascent (descent) regime and the biases are often larger in the ascent regime than in the descent regime. PRs are overpredicted in both regimes; however the observed and reanalyzed PRs over the ascent regime are an order of magnitude larger than those over the descent regime, indicating different types of clouds exist in these two regimes. Based upon the Atmospheric Radiation Measurement Program ground-based and CM

  10. On the optimal method for evaluating cloud products from passive satellite imagery using CALIPSO-CALIOP data: example investigating the CM SAF CLARA-A1 dataset

    Directory of Open Access Journals (Sweden)

    K.-G. Karlsson

    2013-02-01

    Full Text Available A method for detailed evaluation of a new satellite-derived global 28-yr cloud and radiation climatology (Climate Monitoring SAF Cloud, Albedo and Radiation dataset from AVHRR data, named CLARA-A1 from polar orbiting NOAA and Metop satellites is presented. The method combines 1 km and 5 km resolution cloud datasets from the CALIPSO-CALIOP cloud lidar for estimating cloud detection limitations and the accuracy of cloud top height estimations.

    Cloud detection is shown to work efficiently for clouds with optical thicknesses above 0.30 except for at twilight conditions when this value increases to 0.45. Some misclassifications generating erroneous clouds over land surfaces in semi-arid regions in the sub-tropical and tropical regions are revealed. In addition, a substantial fraction of all clouds remains undetected in the Polar regions during the polar winter season due to the lack of or an inverted temperature contrast between Earth surfaces and clouds.

    Subsequent cloud top height evaluation took into account the derived information about the cloud detection limits. It was shown that this has fundamental importance for the achieved results. An overall bias of −274 m was achieved compared to a bias of −2762 m if no measures were taken to compensate for cloud detection limitations. Despite this improvement it was concluded that high-level clouds still suffer from substantial height underestimations while the opposite is true for low-level (boundary layer clouds.

    The validation method and the specifically collected satellite dataset with optimal matching in time and space are suggested for a wider use in the future for evaluation of other cloud retrieval methods based on passive satellite imagery.

  11. All satellites total ozone evaluation in the tropics by comparison with SAOZ-NDACC ground-based measurements

    Science.gov (United States)

    Pommereau, Jean-Pierre; Lerot, Christophe; Van Roozendael, Michel; Goutail, Florence; Pazmino, Andrea; Frihi, Aymen; Bekki, Slimane; Clerbaux, Cathy

    2016-07-01

    All satellites total ozone measurements available from SBUV, OMI-T, OMI-D, OMI-CCI, GOME-CCI, GOME2-CCI, SCIAMACHY-CCI, NPP and IASI, since 2001 until 2015 are compared to those provided by the UV-Vis SAOZ/NDACC spectrometer at the two tropical stations of Reunion Island in the Indian Ocean and Bauru in Southern Brazil. The differences between satellites and SAOZ except IASI do show systematic seasonal variations of 0-3% (0-9 DU) amplitude and sharp negative peaks in Jan-Mar in Reunion Is in the austral summer. Whereas the summer negative peaks seen particularly on IASI, OMI-T, NPP and OMI-CCI at Reunion are shown to correlate with hurricanes and those seen in Brazil with high altitude overshooting convective clouds both not properly removed, ozone minima outside these events are shown to correlate with high altitude volcanic plumes impacting all satellites as well as ground-based total ozone measurements The seasonality of the Sat-SAOZ difference of varying amplitude from 0 to 3% with the satellite is attributed to the satellite retrieval. Surprisingly and though there has been no change in either SAOZ instruments or data analysis processes, the amplitude of the seasonal cycle of the Sat-SAOZ difference reduces in 2012 and drops to less than ± 0.5% (1.5 DU) after 2013 in Reunion Island and less than ±1% in Bauru, reduction for which there is no clear explanation yet. Shown in the presentation will be the demonstration of the impact of hurricanes, high altitude convective clouds and volcanic plumes on satellites total ozone retrievals, followed by a discussion of possible causes of seasonality of Sat-SAOZ amplitude drop after 2012.

  12. Application of a concept development process to evaluate process layout designs using value stream mapping and simulation

    Directory of Open Access Journals (Sweden)

    Ki-Young Jeong

    2011-07-01

    Full Text Available Purpose: We propose and demonstrate a concept development process (CDP as a framework to solve a value stream mapping (VSM related process layout design optimization problem.Design/methodology/approach: A case study approach was used to demonstrate the effectiveness of CDP framework in a portable fire extinguisher manufacturing company. To facilitate the CDP application, we proposed the system coupling level index (SCLI and simulation to evaluate the process layout design concepts.Findings: As part of the CDP framework application, three process layout design concepts - current layout (CL, express lane layout (ELL and independent zone layout (IZL - were generated. Then, the SCLI excluded CL and simulation selected IZL as the best concept. The simulation was also applied to optimize the performance of IZL in terms of the number of pallets. Based on this case study, we concluded that CDP framework worked well.Research limitations/implications: The process layout design optimization issue has not been well addressed in the VSM literature. We believe that this paper initiated the relevant discussion by showing the feasibility of CDP as a framework in this issue.Practical implications: The CDP and SCLI are very practice-oriented approaches in the sense that they do not require any complex analytical knowledge.Originality/value: We discussed a not well-addressed issue with a systematic framework. In addition, the SCLI presented was also unique.

  13. Characterization of the CTS 12 and 14 GHz communications links - Preliminary measurements and evaluation. [Communications Technology Satellite

    Science.gov (United States)

    Ippolito, L. J.

    1976-01-01

    The Communications Link Characterization Experiment is designed to characterize the radio frequency links of the Communications Technology Satellite. The experiment is twofold: (1) it will study the natural characteristics in the CTS frequency bands (14 GHz uplink, and 12 GHz downlink) including attenuation and signal degradation due primarily to absorption and scattering induced by precipitation, and (2) it will perform environmental measurements for the characterization of man-made, earth-based signals which could interfere with the uplink frequency bands of the satellite.

  14. Evaluation of Aerosol Pollution Determination From MODIS Satellite Retrievals for Semi-Arid Reno, NV, USA with In-Situ Measurements

    Science.gov (United States)

    Loria-Salazar, S. Marcela

    The aim of the present work is to carry out a detailed analysis of ground and columnar aerosol properties obtained by in-situ Photoacoustic and Integrated Nephelometer (PIN), Cimel CE-318 sunphotometer and MODIS instrument onboard Aqua and Terra satellites, for semi-arid Reno, Nevada, USA in the local summer months of 2012. Satellite determination of local aerosol pollution is desirable because of the potential for broad spatial and temporal coverage. However, retrieval of quantitative measures of air pollution such as Aerosol Optical Depth (AOD) from satellite measurements is challenging because of the underlying surface albedo being heterogeneous in space and time. Therefore, comparisons of satellite retrievals with measurements from ground-based sun photometers are crucial for validation, testing, and further development of instruments and retrieval algorithms. Ground-based sunphotometry and in-situ ground observations show that seasonal weather changes and fire plumes have great influence on the atmosphere aerosol optics. The Apparent Optical Height (AOH) follows the shape of the development of the Convective Boundary Layer (CBL) when fire conditions were not present. However, significant fine particle optical depth was inferred beyond the CBL thereby complicating the use of remote sensing measurements for near-ground aerosol pollution measurements. A meteorological analysis was performed to help diagnose the nature of the aerosols above Reno. The calculation of a Zephyr index and back trajectory analysis demonstrated that a local circulation often induces aerosol transport from Northern CA over the Sierra Nevada Mountains that doubles the Aerosol Optical Depth (AOD) at 500 nm. Sunphotometer measurements were used as a `ground truth' for satellite retrievals to evaluate the current state of the science retrievals in this challenging location. Satellite retrieved for AOD showed the presence of wild fires in Northern CA during August. AOD retrieved using the

  15. Evaluation of a large capacity heat pump concept for active cooling of hypersonic aircraft structure

    Science.gov (United States)

    Pagel, L. L.; Herring, R. L.

    1978-01-01

    Results of engineering analyses assessing the conceptual feasibility of a large capacity heat pump for enhancing active cooling of hypersonic aircraft structure are presented. A unique heat pump arrangement which permits cooling the structure of a Mach 6 transport to aluminum temperatures without the aid of thermal shielding is described. The selected concept is compatible with the use of conventional refrigerants, with Freon R-11 selected as the preferred refrigerant. Condenser temperatures were limited to levels compatible with the use of conventional refrigerants by incorporating a unique multipass condenser design, which extracts mechanical energy from the hydrogen fuel, prior to each subsequent pass through the condenser. Results show that it is technically feasible to use a large capacity heat pump in lieu of external shielding. Additional analyses are required to optimally apply this concept.

  16. The Stock Concept Applicability for the Economic Evaluation of Marine Ecosystem Exploitation

    DEFF Research Database (Denmark)

    Ravn-Jonsen, Lars

    Stock models, in which production is interpreted as if it were the population growth of a stock, have been the preferred tool for fishery economics since Clark and Munro (1975) introduced capital theory in these models. Ravn-Jonsen (2009) applied capital theory to a model in which the production ...... of a stock. The concept of a stock is rather an illusion, as is the concept of an optimal stock level. It is essential to liberate fishery economics from a simplified view of population and communities.......Stock models, in which production is interpreted as if it were the population growth of a stock, have been the preferred tool for fishery economics since Clark and Munro (1975) introduced capital theory in these models. Ravn-Jonsen (2009) applied capital theory to a model in which the production...

  17. Radiation Evaluation and Concept Development for Analog Probability Processing Technology Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We will perform lab bench evaluations using Analog Devices Lyric Labs evaluation hardware as well as the NASA/GSFC Radiation Effects and Analysis Group...

  18. Seizure prediction in epilepsy: from circadian concepts via probabilistic forecasting to statistical evaluation.

    Science.gov (United States)

    Schelter, Björn; Feldwisch-Drentrup, Hinnerk; Ihle, Matthias; Schulze-Bonhage, Andreas; Timmer, Jens

    2011-01-01

    Seizure prediction performance is hampered by high numbers of false predictions. Here we present an approach to reduce the number of false predictions based on circadian concepts. Based on eight representative patients we demonstrate that this approach increases the performance considerably. The fraction of patients for whom we found a significant seizure prediction performance was increased from 25% to 38% by accounting for circadian dependencies.

  19. [AN EVALUATION OF JUSTICE AND RIGHT TO HEALTH CONCEPTS IN THE PERSPECTIVES OF ETHICAL THEORIES].

    Science.gov (United States)

    Ekmekçi, Perihan Elif; Arda, Berna

    Right to health is considered as a fundamental human right. However the realization of right to health is facing obstacles due to the scarce resources which are needed for the provision of health services. Besides the vast technological improvements in medical area leads to the development of diagnosis and treatment possibilities each and every day. Thus, the provision of health services becomes a subject of distributive justice. To define the concept of justice, first one should identify the conditions of demanding right to have something and then determine how and who is obliged to give the deserved. Ethical theories form their own paradigms of acting right regarding their anchor points and priority values. The basic concepts such as justice or right to health are considered and conceptualized within the paradigms of the ethical theories. Thus some ethical theories consider right to health as a natural constituent of human being, while some may consider it contextual and others may reject it completely. In a similar vein, justice and related concepts of justice such as formal and material principles of justice differ regarding the paradigm of the ethical theory in which we position ourselves. The paradigms of ethical theories demand different approaches from each other both in defining the concepts and implementations in practical life. This paper sets forth how justice and right to health is conceptualized in the virtue ethics, deontological ethics, liberal ethical theory and communitarian ethical theories. To this end first the general frame of each ethical theory and how justice is conceptualized within this frame is defined. Following that a discussion of the possibility of justification of the right to health within the context of ethical theory is perused.

  20. Exploratory Research on Novel Coal Liquefaction Concept - Task 2: Evaluation of Process Steps.

    Energy Technology Data Exchange (ETDEWEB)

    Brandes, S.D.; Winschel, R.A.

    1997-05-01

    A novel direct coal liquefaction technology is being investigated in a program being conducted by CONSOL Inc. with the University of Kentucky, Center for Applied Energy Research and LDP Associates under DOE Contract DE-AC22-95PC95050. The novel concept consists of a new approach to coal liquefaction chemistry which avoids some of the inherent limitations of current high-temperature thermal liquefaction processes. The chemistry employed is based on hydride ion donation to solubilize coal at temperatures (350-400{degrees}C) significantly lower than those typically used in conventional coal liquefaction. The process concept being explored consists of two reaction stages. In the first stage, the coal is solubilized by hydride ion donation. In the second, the products are catalytically upgraded to acceptable refinery feedstocks. The program explores not only the initial solubilization step, but integration of the subsequent processing steps, including an interstage solids-separation step, to produce distillate products. A unique feature of the process concept is that many of the individual reaction steps can be decoupled, because little recycle around the liquefaction system is expected. This allows for considerable latitude in the process design. Furthermore, this has allowed for each key element in the process to be explored independently in laboratory work conducted under Task 2 of the program.

  1. Global Cost and Weight Evaluation of Fuselage Side Panel Design Concepts

    Science.gov (United States)

    Polland, D. R.; Finn, S. R.; Griess, K. H.; Hafenrichter, J. L.; Hanson, C. T.; Ilcewicz, L. B.; Metschan, S. L.; Scholz, D. B.; Smith, P. J.

    1997-01-01

    This report documents preliminary design trades conducted under NASA contracts NAS1 18889 (Advanced Technology Composite Aircraft Structures, ATCAS) and NAS1-19349 (Task 3, Pathfinder Shell Design) for a subsonic wide body commercial aircraft fuselage side panel section utilizing composite materials. Included in this effort were (1) development of two complete design concepts, (2) generation of cost and weight estimates, (3) identification of technical issues and potential design enhancements, and (4) selection of a single design to be further developed. The first design concept featured an open-section stringer stiffened skin configuration while the second was based on honeycomb core sandwich construction. The trade study cost and weight results were generated from comprehensive assessment of each structural component comprising the fuselage side panel section from detail fabrication through airplane final assembly. Results were obtained in three phases: (1) for the baseline designs, (2) after global optimization of the designs, and (3) the results anticipated after detailed design optimization. A critical assessment of both designs was performed to determine the risk associated with each concept, that is the relative probability of achieving the cost and weight projections. Seven critical technical issues were identified as the first step towards side panel detailed design optimization.

  2. Concept theory

    DEFF Research Database (Denmark)

    Hjørland, Birger

    2009-01-01

      Concept theory is an extremely broad, interdisciplinary and complex field of research related to many deep fields with very long historical traditions without much consensus. However, information science and knowledge organization cannot avoid relating to theories of concepts. Knowledge...... organizing systems (e.g. classification systems, thesauri and ontologies) should be understood as systems basically organizing concepts and their semantic relations. The same is the case with information retrieval systems. Different theories of concepts have different implications for how to construe......, evaluate and use such systems. Based on "a post-Kuhnian view" of paradigms this paper put forward arguments that the best understanding and classification of theories of concepts is to view and classify them in accordance with epistemological theories (empiricism, rationalism, historicism and pragmatism...

  3. Single-Nucleotide Polymorphism-Microarray Ploidy Analysis of Paraffin-Embedded Products of Conception in Recurrent Pregnancy Loss Evaluations.

    Science.gov (United States)

    Maslow, Bat-Sheva L; Budinetz, Tara; Sueldo, Carolina; Anspach, Erica; Engmann, Lawrence; Benadiva, Claudio; Nulsen, John C

    2015-07-01

    To compare the analysis of chromosome number from paraffin-embedded products of conception using single-nucleotide polymorphism (SNP) microarray with the recommended screening for the evaluation of couples presenting with recurrent pregnancy loss who do not have previous fetal cytogenetic data. We performed a retrospective cohort study including all women who presented for a new evaluation of recurrent pregnancy loss over a 2-year period (January 1, 2012, to December 31, 2013). All participants had at least two documented first-trimester losses and both the recommended screening tests and SNP microarray performed on at least one paraffin-embedded products of conception sample. Single-nucleotide polymorphism microarray identifies all 24 chromosomes (22 autosomes, X, and Y). Forty-two women with a total of 178 losses were included in the study. Paraffin-embedded products of conception from 62 losses were sent for SNP microarray. Single-nucleotide polymorphism microarray successfully diagnosed fetal chromosome number in 71% (44/62) of samples, of which 43% (19/44) were euploid and 57% (25/44) were noneuploid. Seven of 42 (17%) participants had abnormalities on recurrent pregnancy loss screening. The per-person detection rate for a cause of pregnancy loss was significantly higher in the SNP microarray (0.50; 95% confidence interval [CI] 0.36-0.64) compared with recurrent pregnancy loss evaluation (0.17; 95% CI 0.08-0.31) (P=.002). Participants with one or more euploid loss identified on paraffin-embedded products of conception were significantly more likely to have an abnormality on recurrent pregnancy loss screening than those with only noneuploid results (P=.028). The significance remained when controlling for age, number of losses, number of samples, and total pregnancies. These results suggest that SNP microarray testing of paraffin-embedded products of conception is a valuable tool for the evaluation of recurrent pregnancy loss in patients without prior fetal

  4. Inferring past land use-induced changes in surface albedo from satellite observations: a useful tool to evaluate model simulations

    Directory of Open Access Journals (Sweden)

    J. P. Boisier

    2013-03-01

    Full Text Available Regional cooling resulting from increases in surface albedo has been identified in several studies as the main biogeophysical effect of past land use-induced land cover changes (LCC on climate. However, the amplitude of this effect remains quite uncertain due to, among other factors, (a uncertainties in the extent of historical LCC and, (b differences in the way various models simulate surface albedo and more specifically its dependency on vegetation type and snow cover. We derived monthly albedo climatologies for croplands and four other land cover types from the Moderate Resolution Imaging Spectroradiometer (MODIS satellite observations. We then reconstructed the changes in surface albedo between preindustrial times and present-day by combining these climatologies with the land cover maps of 1870 and 1992 used by seven land surface models (LSMs in the context of the LUCID ("Land Use and Climate: identification of robust Impacts" intercomparison project. These reconstructions show surface albedo increases larger than 10% (absolute in winter, and larger than 2% in summer between 1870 and 1992 over areas that experienced intense deforestation in the northern temperate regions. The historical surface albedo changes estimated with MODIS data were then compared to those simulated by the various climate models participating in LUCID. The inter-model mean albedo response to LCC shows a similar spatial and seasonal pattern to the one resulting from the MODIS-based reconstructions, that is, larger albedo increases in winter than in summer, driven by the presence of snow. However, individual models show significant differences between the simulated albedo changes and the corresponding reconstructions, despite the fact that land cover change maps are the same. Our analyses suggest that the primary reason for those discrepancies is how LSMs parameterize albedo. Another reason, of secondary importance, results from differences in their simulated snow extent

  5. Concept and methodology for evaluating core damage frequency considering failure correlation at multi units and sites and its application

    Energy Technology Data Exchange (ETDEWEB)

    Ebisawa, K.; Teragaki, T.; Nomura, S. [Former Incorporated Administrative Agency, Japan Nuclear Safety Organization (Japan); Abe, H., E-mail: Hiroshi_abe@nsr.go.jp [Former Incorporated Administrative Agency, Japan Nuclear Safety Organization (Japan); Shigemori, M.; Shimomoto, M. [Mizuho Information & Research Institute, 2-3, Kanda-Nishikicho, Chiyoda-ku, Tokyo (Japan)

    2015-07-15

    Highlights: • We develop a method to evaluate CDF considering failure correlation at multi units. • We develop a procedure to evaluate correlation coefficient between multi components. • We evaluate CDF at two different BWR units using correlation coefficients. • We confirm the validity of method and correlation coefficient through the evaluation. - Abstract: The Tohoku earthquake (Mw9.0) occurred on March 11, 2011 and caused a large tsunami. The Fukushima Daiichi Nuclear Power Plant with six units were overwhelmed by the tsunami and core damage occurred. Authors proposed the concept and method for evaluating core damage frequency (CDF) considering failure correlation at the multi units and sites. Based on the above method, one of authors developed the procedure for evaluating the failure correlation coefficient and response correlation coefficient between the multi components under the strong seismic motion. These method and failure correlation coefficients were applied to two different BWR units and their CDF was evaluated by seismic probabilistic risk assessment technology. Through this quantitative evaluation, the validity of the method and failure correlation coefficient was confirmed.

  6. Safer Conception Methods and Counseling: Psychometric Evaluation of New Measures of Attitudes and Beliefs Among HIV Clients and Providers.

    Science.gov (United States)

    Woldetsadik, Mahlet Atakilt; Goggin, Kathy; Staggs, Vincent S; Wanyenze, Rhoda K; Beyeza-Kashesya, Jolly; Mindry, Deborah; Finocchario-Kessler, Sarah; Khanakwa, Sarah; Wagner, Glenn J

    2016-06-01

    With data from 400 HIV clients with fertility intentions and 57 HIV providers in Uganda, we evaluated the psychometrics of new client and provider scales measuring constructs related to safer conception methods (SCM) and safer conception counselling (SCC). Several forms of validity (i.e., content, face, and construct validity) were examined using standard methods including exploratory and confirmatory factor analysis. Internal consistency was established using Cronbach's alpha correlation coefficient. The final scales consisted of measures of attitudes towards use of SCM and delivery of SCC, including measures of self-efficacy and motivation to use SCM, and perceived community stigma towards childbearing. Most client and all provider measures had moderate to high internal consistency (alphas 0.60-0.94), most had convergent validity (associations with other SCM or SCC-related measures), and client measures had divergent validity (poor associations with depression). These findings establish preliminary psychometric properties of these scales and should facilitate future studies of SCM and SCC.

  7. Design and evaluation of a telemonitoring concept based on NFC-enabled mobile phones and sensor devices.

    Science.gov (United States)

    Morak, Jürgen; Kumpusch, Hannes; Hayn, Dieter; Modre-Osprian, Robert; Schreier, Günter

    2012-01-01

    Utilization of information and communication technologies such as mobile phones and wireless sensor networks becomes more and more common in the field of telemonitoring for chronic diseases. Providing elderly people with a mobile-phone-based patient terminal requires a barrier-free design of the overall user interface including the setup of wireless communication links to sensor devices. To easily manage the connection between a mobile phone and wireless sensor devices, a concept based on the combination of Bluetooth and near-field communication technology has been developed. It allows us initiating communication between two devices just by bringing them close together for a few seconds without manually configuring the communication link. This concept has been piloted with a sensor device and evaluated in terms of usability and feasibility. Results indicate that this solution has the potential to simplify the handling of wireless sensor networks for people with limited technical skills.

  8. Flight evaluation of configuration management system concepts during transition to the landing approach for a powered-lift STOL aircraft

    Science.gov (United States)

    Franklin, J. A.; Innis, R. C.

    1980-01-01

    Flight experiments were conducted to evaluate two control concepts for configuration management during the transition to landing approach for a powered-lift STOL aircraft. NASA Ames' augmentor wing research aircraft was used in the program. Transitions from nominal level-flight configurations at terminal area pattern speeds were conducted along straight and curved descending flightpaths. Stabilization and command augmentation for attitude and airspeed control were used in conjunction with a three-cue flight director that presented commands for pitch, roll, and throttle controls. A prototype microwave system provided landing guidance. Results of these flight experiments indicate that these configuration management concepts permit the successful performance of transitions and approaches along curved paths by powered-lift STOL aircraft. Flight director guidance was essential to accomplish the task.

  9. Evaluation of the satellite-based Global Flood Detection System for measuring river discharge: influence of local factors

    Directory of Open Access Journals (Sweden)

    B. Revilla-Romero

    2014-07-01

    Full Text Available One of the main challenges for global hydrological modelling is the limited availability of observational data for calibration and model verification. This is particularly the case for real time applications. This problem could potentially be overcome if discharge measurements based on satellite data were sufficiently accurate to substitute for ground-based measurements. The aim of this study is to test the potentials and constraints of the remote sensing signal of the Global Flood Detection System for converting the flood detection signal into river discharge values. The study uses data for 322 river measurement locations in Africa, Asia, Europe, North America and South America. Satellite discharge measurements were calibrated for these sites and a validation analysis with in situ discharge was performed. The locations with very good performance will be used in a future project where satellite discharge measurements are obtained on a daily basis to fill the gaps where real time ground observations are not available. These include several international river locations in Africa: Niger, Volta and Zambezi rivers. Analysis of the potential factors affecting the satellite signal was based on a classification decision tree (Random Forest and showed that mean discharge, climatic region, land cover and upstream catchment area are the dominant variables which determine good or poor performance of the measurement sites. In general terms, higher skill scores were obtained for locations with one or more of the following characteristics: a river width higher than 1 km; a large floodplain area and in flooded forest; with a potential flooded area greater than 40%; sparse vegetation, croplands or grasslands and closed to open and open forest; Leaf Area Index > 2; tropical climatic area; and without hydraulic infrastructures. Also, locations where river ice cover is seasonally present obtained higher skill scores. The work provides guidance on the best

  10. Three-month performance evaluation of the Nanometrics, Inc., Libra Satellite Seismograph System in the northern California Seismic Network

    Science.gov (United States)

    Oppenheimer, David H.

    2000-01-01

    In 1999 the Northern California Seismic Network (NCSN) purchased a Libra satellite seismograph system from Nanometrics, Inc to assess whether this technology was a cost-effective and robust replacement for their analog microwave system. The system was purchased subject to it meeting the requirements, criteria and tests described in Appendix A. In early 2000, Nanometrics began delivery of various components of the system, such as the hub and remote satellite dish and mounting hardware, and the NCSN installed and assembled most equipment in advance of the arrival of Nanometrics engineers to facilitate the configuration of the system. The hub was installed in its permanent location, but for logistical reasons the "remote" satellite hardware was initially configured at the NCSN for testing. During the first week of April Nanometrics engineers came to Menlo Park to configure the system and train NCSN staff. The two dishes were aligned with the satellite, and the system was fully operational in 2 days with little problem. Nanometrics engineers spent the remaining 3 days providing hands-on training to NCSN staff in hardware/software operation, configuration, and maintenance. During the second week of April 2000, NCSN staff moved the entire remote system of digitizers, dish assembly, and mounting hardware to Mammoth Lakes, California. The system was reinstalled at the Mammoth Lakes water treatment plant and communications successfully reestablished with the hub via the satellite on 14 April 2000. The system has been in continuous operation since then. This report reviews the performance of the Libra system for the three-month period 20 April 2000 through 20 July 2000. The purpose of the report is to assess whether the system passed the acceptance tests described in Appendix A. We examine all data gaps reported by NCSN "gap list" software and discuss their cause.

  11. Satellites in Canadian broadcasting

    Science.gov (United States)

    Siocos, C. A.

    The involvement of Canadian broadcasting and related enterprises in satellite telecommunications is surveyed. This includes point-to-point transmissions and direct ones to the general public. The mode of such utilizations is indicated in both these cases. For the forthcoming DBS systems the many types of service offerings and utilization concepts under discussion elasewhere are presented as well as the business prospects and regulatory climate offering them.

  12. Evaluation of Self-Concept and Emotional-Behavioral Functioning of Children with Brachial Plexus Birth Injury

    Science.gov (United States)

    Belfiore, Lori A.; Rosen, Carol; Sarshalom, Rachel; Grossman, Leslie; Sala, Debra A.; Grossman, John A. I.

    2016-01-01

    Background The reported incidence of brachial plexus birth injury (BPBI) is 0.87 to 2.2 per 1,000 live births. The psychological functioning, including self-concept and emotional-behavioral functioning, of children with BPBI has only been examined to a limited extent. Objective The purpose of this study was to describe the self-concept and emotional-behavioral functioning in children with BPBI from both the child's and parent's perspective. Methods Thirty-one children with BPBI, mean age 11 years 1 month, completed the Draw A Person: Screening Procedure for Emotional Disturbance (DAP:SPED) and Piers Harris Children's Self-Concept Scale (PHCSCS). The parents answered questions from the Behavior Assessment System for Children, Parent Rating Scales (BASC-2 PRS). Results The scores from the DAP:SPED drawings showed further evaluation was not strongly indicated in the majority of the children. The PHCSCS Total score demonstrated that the children had a strongly positive self-concept. The parental responses to the BASC-2 PRS indicated that few children were at risk or in the clinically significant range for the four composite scores and all of the component clinical or adaptive scales. Gender comparison revealed females exhibited greater anxiety than males. Conclusion Both children and parents reported a positive psychological well-being for the majority of the children. Parents had greater concerns about their child's social-emotional functioning, particularly anxiety. An interdisciplinary approach (occupational therapy evaluation, clinical observation, and parental interview) is necessary to determine the need for mental health referral. PMID:28077960

  13. Development and evaluation of RapTAT: a machine learning system for concept mapping of phrases from medical narratives.

    Science.gov (United States)

    Gobbel, Glenn T; Reeves, Ruth; Jayaramaraja, Shrimalini; Giuse, Dario; Speroff, Theodore; Brown, Steven H; Elkin, Peter L; Matheny, Michael E

    2014-04-01

    Rapid, automated determination of the mapping of free text phrases to pre-defined concepts could assist in the annotation of clinical notes and increase the speed of natural language processing systems. The aim of this study was to design and evaluate a token-order-specific naïve Bayes-based machine learning system (RapTAT) to predict associations between phrases and concepts. Performance was assessed using a reference standard generated from 2860 VA discharge summaries containing 567,520 phrases that had been mapped to 12,056 distinct Systematized Nomenclature of Medicine - Clinical Terms (SNOMED CT) concepts by the MCVS natural language processing system. It was also assessed on the manually annotated, 2010 i2b2 challenge data. Performance was established with regard to precision, recall, and F-measure for each of the concepts within the VA documents using bootstrapping. Within that corpus, concepts identified by MCVS were broadly distributed throughout SNOMED CT, and the token-order-specific language model achieved better performance based on precision, recall, and F-measure (0.95±0.15, 0.96±0.16, and 0.95±0.16, respectively; mean±SD) than the bag-of-words based, naïve Bayes model (0.64±0.45, 0.61±0.46, and 0.60±0.45, respectively) that has previously been used for concept mapping. Precision, recall, and F-measure on the i2b2 test set were 92.9%, 85.9%, and 89.2% respectively, using the token-order-specific model. RapTAT required just 7.2ms to map all phrases within a single discharge summary, and mapping rate did not decrease as the number of processed documents increased. The high performance attained by the tool in terms of both accuracy and speed was encouraging, and the mapping rate should be sufficient to support near-real-time, interactive annotation of medical narratives. These results demonstrate the feasibility of rapidly and accurately mapping phrases to a wide range of medical concepts based on a token-order-specific naïve Bayes model and

  14. Institutional arrangements for the reduction of proliferation risks formulation, evaluation, and implementation of institutional concepts

    Energy Technology Data Exchange (ETDEWEB)

    Kratzer, M.B.; Wonder, E.F.; Gray, J.E.; Shantzis, S.B.; Sievering, N.F.; Paige, H.W.; Jones, B.M.

    1979-12-01

    The purpose of this study was to: (1) identify alternative institutional arrangements applicable to the sensitive steps in the back-end of the fuel cycle that might reduce their associated proliferation risks; and (2) assess their advantages and disadvantages from the standpoint of nonproliferation effectiveness and political, economic, and operational acceptability. The concept of international or multinational custody of sensitive materials and facilities was found to offer a high degree of proliferation resistance and to likely be more acceptable to prospective participants than other institutional arrangements that intrude upon proprietary areas, such as facility ownership and management.

  15. Robot-assisted shopping for the visually impaired: proof-of-concept design and feasibility evaluation.

    Science.gov (United States)

    Kulyukin, Vladimir; Gharpure, Chaitanya; Coster, Daniel

    2008-01-01

    This article presents RoboCart, a proof-of-concept prototype of a robotic shopping cart for the visually impaired in supermarkets. RoboCart autonomously leads shoppers to required locations and cues them through synthetic speech and a portable barcode reader to the salient features of the environment sufficient for product retrieval. In a longitudinal pilot feasibility study, visually impaired shoppers (n = 10) used the device to retrieve products in Lee's MarketPlace, a supermarket in Logan, Utah. The main finding is that RoboCart enables visually impaired shoppers to reliably and independently navigate to and retrieve products in a real supermarket.

  16. Experimental evaluation of shape memory alloy actuation technique in adaptive antenna design concepts

    Science.gov (United States)

    Kefauver, W. Neill; Carpenter, Bernie F.

    1994-01-01

    Creation of an antenna system that could autonomously adapt contours of reflecting surfaces to compensate for structural loads induced by a variable environment would maximize performance of space-based communication systems. Design of such a system requires the comprehensive development and integration of advanced actuator, sensor, and control technologies. As an initial step in this process, a test has been performed to assess the use of a shape memory alloy as a potential actuation technique. For this test, an existing, offset, cassegrain antenna system was retrofit with a subreflector equipped with shape memory alloy actuators for surface contour control. The impacts that the actuators had on both the subreflector contour and the antenna system patterns were measured. The results of this study indicate the potential for using shape memory alloy actuation techniques to adaptively control antenna performance; both variations in gain and beam steering capabilities were demonstrated. Future development effort is required to evolve this potential into a useful technology for satellite applications.

  17. An Aerodynamic Performance Evaluation of the NASA/Ames Research Center Advanced Concepts Flight Simulator. M.S. Thesis

    Science.gov (United States)

    Donohue, Paul F.

    1987-01-01

    The results of an aerodynamic performance evaluation of the National Aeronautics and Space Administration (NASA)/Ames Research Center Advanced Concepts Flight Simulator (ACFS), conducted in association with the Navy-NASA Joint Institute of Aeronautics, are presented. The ACFS is a full-mission flight simulator which provides an excellent platform for the critical evaluation of emerging flight systems and aircrew performance. The propulsion and flight dynamics models were evaluated using classical flight test techniques. The aerodynamic performance model of the ACFS was found to realistically represent that of current day, medium range transport aircraft. Recommendations are provided to enhance the capabilities of the ACFS to a level forecast for 1995 transport aircraft. The graphical and tabular results of this study will establish a performance section of the ACFS Operation's Manual.

  18. 基于TOPSIS的卫星数传调度策略评价方法%Evaluation Method of Satellite Data Transmission Scheduling Strategy Based on TOPSIS

    Institute of Scientific and Technical Information of China (English)

    赵岳

    2012-01-01

    卫星数传调度策略评价是一类多属性决策问题.对调度策略的选用和提升有重要的理论意义和实际价值.在介绍了卫星数传调度模型和调度策略原理的基础上,构建任务调度实例,获取了调度方案和算法运行的数据.根据所建评价指标体系,应用TOPSIS法综合评价卫星数传调度策略.评价结果表明,STK/Scheduler的五种调度策略的求解能力和适用范围存在较大差异.基于TOPSIS法对卫星数传调度策略进行评价,具有一定的可行性和科学性,能够为调度策略的选择提供参考依据.同时对复杂调度策略的评价有借鉴作用.%Evaluation of satellite data transmission scheduling strategy is a kind of multiple attribute decision making problems with a very important significance for selecting and improve scheduling strategy. Data of scheduling schema and algorithm running on the basis of discussion of satellite data transmission scheduling model and feathers of scheduling strategy principle are got. According to the created evaluation index system, overall evaluations of satellite data transmission scheduling strategy with TOPSIS are maken. The results of evaluation method show that there is a big difference between five scheduling strategies of STK/Scheduler in solving ability and scope of application. Evaluation of satellite data transmission scheduling strategy based on TOPSIS can offer valuable references for selecting scheduling strategy and has some reference for evaluation of complex scheduling strategy with feasibility and scientific nature.

  19. SPARTAN: a global network to evaluate and enhance satellite-based estimates of ground-level particulate matter for global health applications

    Directory of Open Access Journals (Sweden)

    G. Snider

    2014-07-01

    Full Text Available Ground-based observations have insufficient spatial coverage to assess long-term human exposure to fine particulate matter (PM2.5 at the global scale. Satellite remote sensing offers a promising approach to provide information on both short- and long-term exposure to PM2.5 at local-to-global scales, but there are limitations and outstanding questions about the accuracy and precision with which ground-level aerosol mass concentrations can be inferred from satellite remote sensing alone. A key source of uncertainty is the global distribution of the relationship between annual average PM2.5 and discontinuous satellite observations of columnar aerosol optical depth (AOD. We have initiated a global network of ground-level monitoring stations designed to evaluate and enhance satellite remote sensing estimates for application in health effects research and risk assessment. This Surface PARTiculate mAtter Network (SPARTAN includes a global federation of ground-level monitors of hourly PM2.5 situated primarily in highly populated regions and collocated with existing ground-based sun photometers that measure AOD. The instruments, a three-wavelength nephelometer and impaction filter sampler for both PM2.5 and PM10, are highly autonomous. Hourly PM2.5 concentrations are inferred from the combination of weighed filters and nephelometer data. Data from existing networks were used to develop and evaluate network sampling characteristics. SPARTAN filters are analyzed for mass, black carbon, water-soluble ions, and metals. These measurements provide, in a variety of global regions, the key data required to evaluate and enhance satellite-based PM2.5 estimates used for assessing the health effects of aerosols. Mean PM2.5 concentrations across sites vary by an order of magnitude. Initial measurements indicate that the AOD column to PM2.5 ratio is driven temporally primarily by the vertical profile of aerosol scattering; and spatially by a~ more complex interaction

  20. Performance evaluation of a proof-of-concept 70 W internal reforming methanol fuel cell system

    Science.gov (United States)

    Avgouropoulos, G.; Schlicker, S.; Schelhaas, K.-P.; Papavasiliou, J.; Papadimitriou, K. D.; Theodorakopoulou, E.; Gourdoupi, N.; Machocki, A.; Ioannides, T.; Kallitsis, J. K.; Kolb, G.; Neophytides, S.

    2016-03-01

    A proof-of-concept 70 W Internal Reforming Methanol Fuel Cell (IRMFC) stack including Balance-of-Plant (BoP) was designed, assembled and tested. Advent TPS® high-temperature, polymer electrolyte membrane electrode assemblies were employed for fuel cell operation at 200 °C. In order to avoid phosphoric acid poisoning of the reformer, the anode electrocatalyst of each cell was indirectly adjoined, via a separation plate, to a highly active CuMnAlOx catalyst coated onto copper foam, which served as methanol reforming layer. The reformer was in-situ converting the methanol/steam feed to the required hydrogen (internal reforming concept) at 200 °C, which was readily oxidized at the anode electrodes. The operation of the IRMFC was supported through a number of BoP components consisting of a start-up subsystem (air blower, evaporator and monolithic burner), a combined afterburner/evaporator device, methanol/water supply and data acquisition units (reactants/products analysis, temperature control, flow control, system load/output control). Depending on the composition of the liquid MeOH/H2O feed streams, current densities up to 0.18 A cm-2 and power output up to 70 W could be obtained with remarkable repeatability. Specific targets for improvement of the efficiency were identified.

  1. Evaluation of digital object identifier concepts in students of a post graduation course

    Directory of Open Access Journals (Sweden)

    Ricardo Shitsuka

    2016-04-01

    Full Text Available Introduction: More than a million graduate annually in Brazil and many go on to Post Graduation Lato sensu courses. These are important for professional and academic market. These courses is interesting to learn the notions of DOI (Digital Object Identifier, ownership and copyright. Objective: Present assessment of DOI and information management concepts on students. Methodology: We carried out an exploratory research, a qualitative case study of the phenomenon of notions on DOI and related concepts. We interviewed students who were completing their Lato sensu Post Graduation course in a traditional private institution located in the Southeast Brazil. Results: The vast majority on students of this case did not know the DOI and other related information management. Participation in the survey makes them interested in the subject. Conclusion: Few students in this study showed to know on DOI and information management. We associated this phenomenon to the low Brazilian participation into the world scientific production. The completion of work proved to be supportive for the emergence of motivation to change this situation and this type of study shows interesting to uncover ways to enhance national scientific production in the global production.

  2. Viability analysis in biological evaluations: Concepts of population viability analysis, biological population, and ecological scale

    Science.gov (United States)

    Gregory D. Hayward; John R. Squires

    1994-01-01

    Environmental protection strategies often rely on environmental impact assessments. As part of the assessment process biologists are routinely asked to evaluate the effects of management actions on plants and animals. This evaluation often requires that biologists make judgments about the viability of affected populations. However, population viability...

  3. Satellite Communications

    CERN Document Server

    Pelton, Joseph N

    2012-01-01

    The field of satellite communications represents the world's largest space industry. Those who are interested in space need to understand the fundamentals of satellite communications, its technology, operation, business, economic, and regulatory aspects. This book explains all this along with key insights into the field's future growth trends and current strategic challenges. Fundamentals of Satellite Communications is a concise book that gives all of the key facts and figures as well as a strategic view of where this dynamic industry is going. Author Joseph N. Pelton, PhD, former Dean of the International Space University and former Director of Strategic Policy at Intelstat, presents a r

  4. Variation in maternal urinary cortisol profiles across the peri-conceptional period: a longitudinal description and evaluation of potential functions.

    Science.gov (United States)

    Nepomnaschy, P A; Salvante, K G; Zeng, L; Pyles, C; Ma, H; Blais, J C; Wen, L; Barha, C K

    2015-06-01

    How do women's first morning urinary cortisol levels, a marker of stress axis activity, vary during the peri-conceptional period (the 12 weeks around conception)? First morning urinary cortisol follows an overall increasing trajectory across the peri-conceptional period, interrupted by 2 week-long decreases during the week preceding conception and the fifth week following conception. Later gestational stages (i.e. second and third trimesters) are characterized by increasing levels of circulating cortisol. This increase is hypothesized to constitute a response to the energy demands imposed by fetal growth, and the development of energy reserves in preparation for nursing and performing regular activities while carrying pregnancy's extra weight and volume. This study is based on a data set collected as part of a longitudinal, naturalistic investigation into the interactions between the stress (hypothalamic-pituitary-adrenal axis (HPAA)) and reproductive (hypothalamic-pituitary-gonadal axis (HPGA)) axes. Biomarkers of HPAA and HPGA function were quantified in first morning urinary specimens collected every other day from 22 healthy women who conceived a pregnancy during the study. We analyzed the longitudinal within- and between-individual variation in first morning urinary cortisol levels across the 12-week peri-conceptional period. Participants were recruited from two rural, aboriginal, neighboring communities in Guatemala. Cortisol, estradiol and progesterone metabolites (estrone-3-glucuronide and pregnanediol glucuronide, respectively) and hCG levels were quantified in first morning urinary specimens using immunoassays to determine time of conception and confirm pregnancy maintenance. Linear mixed-effects models with regression splines were used to evaluate the magnitude and significance of changes in cortisol trajectories. Overall, maternal first morning urinary cortisol increased from 6 weeks prior to conception (geometric mean ± SD = 58.14 ± 36.00 ng/ml) to 6

  5. Evaluation of the Fourth Millennium Development Goal Realisation using Robust and Nonparametric Tools offered by a Data Depth Concept

    Directory of Open Access Journals (Sweden)

    Kosiorowska Ewa

    2015-06-01

    Full Text Available We briefly communicate the results of nonparametric and robust evaluation of the effects of the Fourth Millennium Development Goal of the United Nations. The main aim of the goal was reducing by two thirds, from 1990-2015, under five month’s child mortality. Our novel analysis was conducted by means of very powerful and user friendly tools offered by the Data Depth Concept being a collection of multivariate techniques basing on multivariate generalizations of quintiles, ranges and order statistics. The results of our analysis are more convincing than the results obtained using classical statistical tools.

  6. Evaluation of the Seasonal and Spatial Lake Level Change Using by Worldview-2 Satellite Images in the Egirdir Lake (Turkey)

    Science.gov (United States)

    Sener, Erhan; Sener, Sehnaz; Uysal, Rahmi; Bulut, Cafer

    2016-08-01

    Eğirdir Lake is located in the Lake District, it is fourth largest lake and the second largest freshwater lake in Turkey. The lake is still drinking water sources in many residential areas. In this study two Worldview-2 satellite imagery which is high resolution 8-band has been used. The imagery covering the whole lake and belongs to date 10.05.2010 and 24.10.2010. Using Coastal Band (1.Band), Blue (2.Band), Green (3.Band), Yellow (4.Band) and Red (5.Band) on that satellite, seasonal water level in the rainy and dry periods in the selected pilot areas of the Eğirdir Lake has been aimed to determine. In this context, firstly Atmospheric Correction is applied to reduce their atmospheric effects. In order to mask of surface water The Normalized Water Different Index (NWDI) has been applied. Then seasonally varying fields has been identified with change analysis applied to two different image.

  7. The Evaluation of Facilitation Process in Building Community Capacity about OVOP Concept in Kenjeran Coastal Area, Surabaya

    Science.gov (United States)

    Handayeni, K. D. M. E.; Santoso, E. B.; Siswanto, V. K.

    2017-07-01

    The concept of One Village One Product (OVOP) is an approach to the development potential of the area in the region to produce products that can compete in the global market, while still having unique characteristics of the area. Bulak District is one of the Kenjeran coastal area in Surabaya, Indonesia. Bulak District has had a great potential of marine products, but still contribute greatly in improving the people's welfare. Total activities of SMEs in the District of Bulak quite a lot, but the resulting product unknown to the wider community and the global marketplace. Activity of facilitation for SMEs society do to build community capacity in the implementation of the concept of OVOP. Based on the results of the evaluation assistance through Wilcoxon Signed Ranks Test result an increased understanding of the community regarding to the five subjects related OVOP concept. There are six factors to note in mentoring activities that need to be considered for the sustainability of community capacity building programs on OVOP.

  8. Digital game-based learning and video games in teacher training. Conception, evaluation and results from Leipzig University

    Directory of Open Access Journals (Sweden)

    Robert Aust

    2014-08-01

    Full Text Available By the beginning of the 21st century, media education on topics such as video games and strategies founded on the concept of Game-Based Learning has become an essential issue in school educational contexts. Continually rising standards in gameplay as well as recent developments in technology, in the gaming community, in the concepts and expectations of the potentials of gaming, have successively changed the perspectives on who is playing what, when and for what purpose, as well as on the consequences, opportunities and problems of gaming itself. The authors of this article designed a seminar at the Faculty of Education at Leipzig University, in which different scenarios of playing computer games in school pedagogical contexts could be tried out, discussed and reflected on. The course was developed, tested and evaluated in cooperation with the Computer Gaming School Leipzig (ComputerSpielSchule Leipzig before and during the summer semester of 2014. The aim was to create a situation in which future teachers and seminar instructors would be able to reflect critically on the opportunities, obstacles and challenges of a sensible integration of entertainment software (such as video games in pedagogical teaching concepts. Theoretical and critical introductions to some selected issues concerning Game-Based Learning and computer games in general as well as hands-on gaming experience (gained in three practical sessions provided the basis for discussion in the seminar.

  9. Further psychometric evaluation of the Japanese version of an academic self-concept scale.

    Science.gov (United States)

    Paik, Chie Matsuzawa; Michael, William B

    2002-05-01

    In the present study, the author replicated earlier research (Paik & Michael, 1999) seeking additional information on the reliability and construct validity of a Japanese academic self-concept scale, a 70-item questionnaire comprising 5 subscales (Aspiration, Anxiety, Academic Interest and Satisfaction, Leadership and Initiative, and Identification vs. Alienation). A sample of 196 Japanese high school students completed the scale. Internal consistency reliability for the 5 subscales ranged from .75 to .87. Confirmatory factor analyses performed on several alternative models showed that the a priori 5-factor model fit the observed data best-a finding consistent with the previous study. Results of Z tests revealed statistically significant score differences between genders and between high and low academic achievers.

  10. Fair Trade Metaphor as a Control Privacy Method for Pervasive Environments: Concepts and Evaluation

    Directory of Open Access Journals (Sweden)

    Abraham Esquivel

    2015-06-01

    Full Text Available This paper presents a proof of concept from which the metaphor of “fair trade” is validated as an alternative to manage the private information of users. Our privacy solution deals with user’s privacy as a tradable good for obtaining environmental services. Thus, users gain access to more valuable services as they share more personal information. This strategy, combined with optimistic access control and transaction registry mechanisms, enhances users’ confidence in the system while encouraging them to share their information, with the consequent benefit for the community. The study results are promising considering the user responses regarding the usefulness, ease of use, information classification and perception of control with the mechanisms proposed by the metaphor.

  11. Evaluation of Learning in Oncology of Undergraduate Nursing with the Use of Concept Mapping.

    Science.gov (United States)

    Trevisani, Mariane; Cohrs, Cibelli Rizzo; de Lara Soares, Mariângela Abate; Duarte, José Marcio; Mancini, Felipe; Pisa, Ivan Torres; De Domenico, Edvane Birelo Lopes

    2016-09-01

    This study aims to identify whether the use of concept mapping (CM) strategy assists a student to extend and revise their expertise in oncology and analyze the abilities developed in a student in order to go through theoretical to practical knowledge. This study is descriptive and qualitative, with 20 undergraduate students of the Undergraduate Nursing Course of Paulista School of Nursing of Federal University of São Paulo, Brazil. The critical incident technique and content analysis were used. There were 12 categories represented by facilities, difficulties, and learning applicability in oncology provided by CM strategy during the surgical and clinical nursing discipline. The graphics resource, CMapTools®, and the clinical case data arranged in mapping for resolution generated an active search and exercise of self-learning in oncology. Despite the challenges of the use of CM as a teaching strategy-pedagogical, the results suggested an increase of autonomy and clinical reasoning in nursing practice.

  12. Fair Trade Metaphor as a Control Privacy Method for Pervasive Environments: Concepts and Evaluation

    Science.gov (United States)

    Esquivel, Abraham; Haya, Pablo; Alamán, Xavier

    2015-01-01

    This paper presents a proof of concept from which the metaphor of “fair trade” is validated as an alternative to manage the private information of users. Our privacy solution deals with user's privacy as a tradable good for obtaining environmental services. Thus, users gain access to more valuable services as they share more personal information. This strategy, combined with optimistic access control and transaction registry mechanisms, enhances users' confidence in the system while encouraging them to share their information, with the consequent benefit for the community. The study results are promising considering the user responses regarding the usefulness, ease of use, information classification and perception of control with the mechanisms proposed by the metaphor. PMID:26087373

  13. Quantitative evaluation of smoke source strengths and impacts by infusing satellite fire- strength measurements in transport models.

    Science.gov (United States)

    Ichoku, C.; Chin, M.; Diehl, T.; Wooster, M.; Roberts, G.; Giglio, L.

    2007-05-01

    Chemical transport models currently derive their smoke emission sources from counts of fire hot spots detected from satellites, usually with single daily overpasses. However, fires vary in size and strength, with a significant diurnal trend, making the use of pixel counts measured at the same time of day very unreliable for estimating smoke sources. Fortunately, the Moderate-resolution Imaging Spectro-radiometer (MODIS) twin sensors onboard the Terra and Aqua satellites, not only detect fires everywhere at four strategic times of day, but also measure their strength in the form of fire radiative power (FRP) or rate of release of fire radiative energy (FRE). FRP is now also being derived from the Spinning Enhanced Visible and Infrared Imager (SEVIRI) sensor onboard the geostationary Meteosat-8 platform, which observes Africa and Europe virtually every 15 mins. The SEVIRI measurements show that MODIS 4-times-a-day measurements capture the essence of the fire diurnal cycle. Therefore, MODIS is currently the only satellite data source ideal for estimating daily smoke emissions globally. In a number of recent studies, FRP has been found to be directly proportional to both the rate of biomass consumption and the rate of smoke aerosol emission. Indeed, (1) a combustion factor (Fc), which relates FRE to burned biomass was established, and (2) a FRE-based emission coefficient (Ce), which is a simple coefficient to convert FRP (or FRE) to smoke aerosol emissions was derived for different parts of the world. The results obtained from satellite have been reproduced in the laboratory, and the ingestion of FRP in models is now being tested using the Goddard Global Ozone Chemistry Aerosol Radiation and Transport (GOCART) model. Although MODIS has been in operation since the last 6 years, regrettably, this rare but formidable data resource it provides (FRP) has been left largely unutilized. In this presentation, we will show the preliminary results of using FRP to improve the

  14. Evaluation of oestrus observation and conception rates in suckling beef cows using whole milk progesterone concentration

    Directory of Open Access Journals (Sweden)

    D.C. Lourens

    2002-07-01

    Full Text Available A 2-sample regime was used to measure whole milk progesterone concentration on the day of oestrus and insemination (Day 0 and 6 days later (Day 6 in a sample of 50 primiparous and 100 multiparous suckling beef cows. Exposure to teaser bulls and observation by cattlemen identified the occurrence of oestrus. Three sets of criteria used to define ovulatory oestrus were compared : a milk progesterone concentration less than 6 nmol / l on Day 0 ; b milk progesterone less than 6 nmol / l on Day 0 and rising to greater than 6 nmol / l on Day 6; c milk progesterone less than 6 nmol / l on Day 0 and rising to greater than 6 nmol / l on Day 6, or cow diagnosed pregnant to 1st insemination. Using only a single milk sample on Day 0 (criterion a would have resulted in the positive predictive value of heat detection being estimated at 98.7%. Using a paired measurement (criterion b resulted in a significantly lower estimate of 84.7%. The inclusion of cows that conceived despite not showing a marked rise in milk progesterone concentration (criterion c resulted in a more accurate estimate of 89.3%. Use of a 2-sample regime also allowed calculation of conception rates while eliminating the effect of heat detection errors. In the cows sampled, of those in ovulatory oestrus that were inseminated, 73.1% conceived to the 1st insemination. These results demonstrate that artificial insemination within a limited breeding season can be successful if nutrition is optimal and management is intensive. The use of a 2-sample milk progesterone test may be a valuable tool in investigating heat detection and conception problems in beef herds in which artificial insemination is used.

  15. A Study of Crowd Ability and its Influence on Crowdsourced Evaluation of Design Concepts

    Science.gov (United States)

    2014-05-01

    adaptive Metropolis-Hastings Markov Chain Monte Carlo (MCMC) algorithm [29–31] that