WorldWideScience

Sample records for satellite concept study

  1. 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...

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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...

  12. 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.

  13. 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.

  14. 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.

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. Induction studies with satellite data

    DEFF Research Database (Denmark)

    Olsen, Nils

    1999-01-01

    analysis of the geomagnetic field is performed, and the Q-response, which is the transfer function between the internal (induced) and the external (inducing) expansion coefficients is determined for a specific frequency. In the second approach, known as the geomagnetic depth sounding method, the C....... This paper reviews and discusses the possibilities for induction studies using high-precision magnetic measurements from low-altitude satellites. The different methods and various transfer functions are presented, with special emphasis on the differences in analysing data from ground stations and from...... satellites. The results of several induction studies with scalar satellite data (from the POGO satellites) and with vector data (from the Magsat mission) demonstrate the ability to probe the Earth's conductivity from space. However, compared to the results obtained with ground data the satellite results...

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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...

  5. 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.

  6. 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

  7. 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.

  8. 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..

  9. 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.

  10. 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...

  11. 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.

  12. 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.

  13. Dynamic communications for small satellites using disruption tolerant network concepts

    NARCIS (Netherlands)

    Giuditta, N.; Gill, E.K.A.; Fernández, B.; Isaac, D.

    2009-01-01

    New network technologies are providing interconnectivity in areas previously unheard of. One of these novel technologies, named Disruption Tolerant Networking (DTN), shows promise for the space industry. In order to study its suitability for University projects, a model of a University space mission

  14. 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.

  15. Satellite Contributions to Global Change Studies

    Science.gov (United States)

    Parkinson, Claire L.

    2009-01-01

    sophisticated climate models, in situ process studies, and data sets that extend back well before the introduction of satellite technology. Nonetheless, the repetitive, global view provided by satellites is contributing in a major way to our improved recognition of how the Earth im changing, a recognition that is none too soon in view of the magnitude of the impacts that humans can now have.

  16. Globally Gridded Satellite observations for climate studies

    Science.gov (United States)

    Knapp, K.R.; Ansari, S.; Bain, C.L.; Bourassa, M.A.; Dickinson, M.J.; Funk, C.; Helms, C.N.; Hennon, C.C.; Holmes, C.D.; Huffman, G.J.; Kossin, J.P.; Lee, H.-T.; Loew, A.; Magnusdottir, G.

    2011-01-01

    Geostationary satellites have provided routine, high temporal resolution Earth observations since the 1970s. Despite the long period of record, use of these data in climate studies has been limited for numerous reasons, among them that no central archive of geostationary data for all international satellites exists, full temporal and spatial resolution data are voluminous, and diverse calibration and navigation formats encumber the uniform processing needed for multisatellite climate studies. The International Satellite Cloud Climatology Project (ISCCP) set the stage for overcoming these issues by archiving a subset of the full-resolution geostationary data at ~10-km resolution at 3-hourly intervals since 1983. Recent efforts at NOAA's National Climatic Data Center to provide convenient access to these data include remapping the data to a standard map projection, recalibrating the data to optimize temporal homogeneity, extending the record of observations back to 1980, and reformatting the data for broad public distribution. The Gridded Satellite (GridSat) dataset includes observations from the visible, infrared window, and infrared water vapor channels. Data are stored in Network Common Data Format (netCDF) using standards that permit a wide variety of tools and libraries to process the data quickly and easily. A novel data layering approach, together with appropriate satellite and file metadata, allows users to access GridSat data at varying levels of complexity based on their needs. The result is a climate data record already in use by the meteorological community. Examples include reanalysis of tropical cyclones, studies of global precipitation, and detection and tracking of the intertropical convergence zone.

  17. 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.

  18. 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.

  19. Satellite animal tracking feasibility studies

    Science.gov (United States)

    Buechner, H. K.

    1975-01-01

    A study was initiated in Tsavo National Park to determine movements and home ranges of individual elephants and their relations to overall distribution patterns and environmental factors such as rainfall. Methods used were radio tracking and observations of visually identifiable individuals. Aerial counts provided data on overall distribution. Two bulls and two cows were radio-tagged in Tsavo West and two bulls and four cows in Tsavo East, providing home range and movement data. The movements of individuals were useful in interpreting relatively major shifts in elephant distribution. Results point to the following preliminary conclusions: (1) elephants in the Tsavo area undertook long distance movements in fairly direct response to localized rainfall; (2) a subdivision of the overall population into locally distinct units may exist during the dry season but did not occur after significant rainfall; and (3) food appears to be the primary factor governing movements and distribution of elephants in the area.

  20. Induction studies with satellite data

    DEFF Research Database (Denmark)

    Olsen, Nils

    1999-01-01

    -response, which is the transfer function between the magnetic vertical component and the horizontal derivative of the horizontal components, is determined. If one of these transfer functions is known for several frequencies, models of the electrical conductivity in the Earth's interior can be constructed...... for observations lasting several years, which helps to reduce the statistical error of the estimated response functions. Two methods are used to study the electrical conductivity of the Earth's mantle in the period range from hours to months. In the first, known as the potential method, a spherical harmonic...... analysis of the geomagnetic field is performed, and the Q-response, which is the transfer function between the internal (induced) and the external (inducing) expansion coefficients is determined for a specific frequency. In the second approach, known as the geomagnetic depth sounding method, the C...

  1. A preliminary study on dead geostationary satellite removal

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The collision between satellites IRIDIUM 33 and COSMOS 2251 indicated that the clash of two on-orbit satellites was becoming an inevitable reality. Our calculation with the two-line orbit element by NORAD showed that some two geostationary satellites had approached very close in July 2009. Therefore, more attention should be given to avoid such collisions. This paper analyzes the orbital long-term variation of a dead satellite drifting in the geostationary orbit. Also, the negative effects posed by dead satellites upon the on-orbit operational geostationary satellites are studied. Then the paper proposes a novel idea to launch a satellite sweeper whose purpose is to collect the on-orbit dead satellites and help them de-orbit to a "graveyard". The satellite sweeper consists of a parent satellite and a child satellite. The child satellite collects a dead satellite and transfers it to a higher orbit. The parent satellite stationed in the geostationary orbit is in charge of refueling the child satellite. The strategy of maneuver and rendezvous is presented and a series of formulas are derived. The analysis results show that our method to clean the geostationary orbital zone is practical and fuel-saving. With the help of just a few satellite sweepers, we can gain a clean environment of geostationary orbit environment again.

  2. The NOAA Satellite Observing System Architecture Study

    Science.gov (United States)

    Volz, Stephen; Maier, Mark; Di Pietro, David

    2016-01-01

    NOAA is beginning a study, the NOAA Satellite Observing System Architecture (NSOSA) study, to plan for the future operational environmental satellite system that will follow GOES and JPSS, beginning about 2030. This is an opportunity to design a modern architecture with no pre-conceived notions regarding instruments, platforms, orbits, etc. The NSOSA study will develop and evaluate architecture alternatives to include partner and commercial alternatives that are likely to become available. The objectives will include both functional needs and strategic characteristics (e.g., flexibility, responsiveness, sustainability). Part of this study is the Space Platform Requirements Working Group (SPRWG), which is being commissioned by NESDIS. The SPRWG is charged to assess new or existing user needs and to provide relative priorities for observational needs in the context of the future architecture. SPRWG results will serve as input to the process for new foundational (Level 0 and Level 1) requirements for the next generation of NOAA satellites that follow the GOES-R, JPSS, DSCOVR, Jason-3, and COSMIC-2 missions.

  3. 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

    assessed the ability of satellite-based relays working above GEO in conjunction with Earth ground stations. Many of these focused on the trade between space relay and direct-to-Earth station links5,6,7. Several others focused on top-level architecture based on relays at various destinations8,9,10,11,12. Much has changed in terms of microwave and optical technology since the publication of the referenced papers; Ka-band communication systems are being deployed, optical communication is being demonstrated, and spacecraft buses are becoming increasingly more functional and operational. A design concept study was undertaken to access the potential for deploying a Small Space-Based Satellite (SSBS) relay capable of serving missions between LEO and NEO. The needs of future human exploration missions were analyzed, and a notional relay-based architecture concept was generated as shown in Fig. 1. Relay satellites in Earth through cis-Lunar orbits are normally located in stable orbits requiring low fuel consumption. Relay satellites for Mars orbit are normally selected based on the mission requirement and projected fuel consumption. Relay satellites have extreme commonalities of functions between them, differing only in the redundancy and frequencies used; therefore, the relay satellite in GEO was selected for further analysis since it will be the first step in achieving a relay-based architecture for human exploration missions (see Fig.Figure 2). The mission design methodology developed by the Collaborative Modeling for Parametric Assessment of Space Systems (COMPASS) team13 was used to produce the satellite relay design and to perform various design trades. At the start of the activity, the team was provided with the detailed concept of the notional architecture and the system and communication payload drivers.

  4. Near threshold studies of photoelectron satellites

    Energy Technology Data Exchange (ETDEWEB)

    Heimann, P.A.

    1986-11-01

    Photoelectron spectroscopy and synchrotron radiation have been used to study correlation effects in the rare gases: He, Ne, Ar, Kr, and Xe. Two kinds of time-of-flight electron analyzers were employed to examine photoionization very close to threshold and at higher kinetic energies. Partial cross sections and angular distributions have been measured for a number of photoelectron satellites. The shake-off probability has been determined at some inner-shell resonances. 121 refs., 28 figs., 13 tabs.

  5. 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

  6. Review and Development on the Studies of Chinese Meteorological Satellite and Satellite Meteorology

    Institute of Scientific and Technical Information of China (English)

    FANG Zongyi; XU Jianmin; ZHAO Fengsheng

    2006-01-01

    Meteorological satellite and satellite meteorology are the fastest developing new branches in the atmospheric sciences. Today the meteorological satellite has become a key element in the global atmospheric sounding system while the satellite meteorology is covering the main components of earth's system science.This article describes the major achievements that China has made in these fields in the past 30 years.The following contents are involved: (1) History and present status of China's meteorological satellites. It covers the development, launch, operation, technical parameters of China's polar and geostationary meteorological satellites. (2) Major achievements on remote sensing principle and method. It describes the retrieval of atmospheric temperature and humidity profiles, cloud character retrieval, aerosol character retrieval, precipitation retrieval as well as the generation of cloud wind. (3) Achievement on the studies of meteorological satellite data application. This part covers the applications of meteorological satellite data to weather analysis and forecast, numerical forecast, climate monitoring, and prediction of short-term climate change. Besides, the new results on data assimilation, climate monitoring, and forecast are also included.

  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. Spacecraft (Mobile Satellite) configuration design study

    Science.gov (United States)

    1985-01-01

    The relative costs to procure and operate a two-satellite mobile satellite system designed to operate either in the UHF band of the L Band, and with several antenna diameter options in each frequency band was investigated. As configured, the size of the spacecraft is limited to the current RCA Series 4000 Geosynchronous Communications Spacecraft bus, which spans the range from 4000 to 5800 pounds in the transfer orbit. The Series 4000 bus forms the basis around which the Mobile Satellite transponder and associated antennas were appended. Although the resultant configuration has little outward resemblance to the present Series 4000 microwave communications spacecraft, the structure, attitude control, thermal, power, and command and control subsystems of the Series 4000 spacecraft are all adapted to support the Mobile Satellite mission.

  9. TDRSS/user satellite timing study

    Science.gov (United States)

    Mcgregor, D.; Douglas, F.; Kaul, R.

    1976-01-01

    A timing analysis for data readout through the Tracking and Data Relay Satellite System (TDRSS) was presented. Various time tagging approaches were considered and the resulting accuracies delineated. The TDRSS was also defined and described in detail.

  10. 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.

  11. 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...

  12. 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.

  13. 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.

  14. Versatile Satellite Architecture and Technology: A New Architecture for Low Cost Satellite Missions for Solar-Terrestrial Studies

    Science.gov (United States)

    Cook, T. A.; Chakrabarti, S.; Polidan, R.; Jaeger, T.; Hill, L.

    2011-12-01

    Early in the 20th century, automobiles appeared as extraordinary vehicles - and now they are part of life everywhere. Late in the 20th century, internet and portable phones appeared as innovations - and now omni-present requirements. At mid-century, the first satellites were launched into space - and now 50 years later - "making a satellite" remains in the domain of highly infrequent events. Why do all universities and companies not have their own satellites? Why is the work force capable of doing so remarkably small? Why do highly focused science objectives that require just a glimpse from space never get a chance to fly? Historically, there have been two primary impediments to place an experiment in orbit - high launch costs and the high cost of spacecraft systems and related processes. The first problem appears to have been addressed through the availability of several low-cost (< $10M) commercial launch opportunities. The Versatile Satellite Architecture and Technology (VerSAT) will address the second. Today's space missions are often large, complex and require development times typically a decade from conception to execution. In present risk-averse scenario, the huge expense of these one-of-a-kind mission architecture can only be justified if the technology required to make orders of magnitude gains is flight-proven at the time mission conception. VerSAT will complement these expensive missions which are "too large to fail" and the CUBESATs. A number of Geospace science experiments that could immediately take advantage of VerSAT have been identified. They range from the study of fundamental questions of the "ignorosphere" from a single satellite lasting a few days - a region of space that was probed once about 40 years ago, to a constellation of satellites which will disentangle the space and time ambiguity of the variability of ionospheric structures and their link to the storms in the Sun to long-term studies of the Sun-Earth system. VerSAT is a true

  15. 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...

  16. 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.

  17. A satellite study of dayside auroral conjugacy

    Directory of Open Access Journals (Sweden)

    H. B. Vo

    Full Text Available A study of dayside auroral conjugacy has been done using the cleft/boundary layer auroral particle boundaries observed by the DMSP-F7 satellite in the southern hemisphere and the global UV auroral images taken by the Viking spacecraft in the northern hemisphere. The 22 events have been studied on the basis of an internal IGRF 1985 magnetic field; it is shown that there is a displacement of up to 4° in latitude from the conjugate points with the northern aurora appearing to be located poleward of the conjugate point. No local time dependence of the north-south auroral location difference was seen. The use of a more realistic magnetic field model for tracing field lines which incorporates the dipole tilt angle and Kp index, the Tsyganenko 1987 long model plus the IGRF 1985 internal magnetic field model, appears to organize the data better. Although with this external plus internal model some tracings did not close in the opposite hemisphere, 70% of those that did indicated satisfactory conjugacy. The study shows that the degree of auroral conjugacy is dependent upon the accuracy of the magnetic field model used to trace to the conjugate point, especially in the dayside region where the field lines can either go to the dayside magnetopause near the subsolar point or sweep all the way back to the flanks of the magnetotail. Also the discrepancy in the latitude of northern and southern aurora can be partially explained by the displacement of the neutral sheet (source region of the aurora by the dipole tilt effect.

  18. Toward lean satellites reliability improvement using HORYU-IV project as case study

    Science.gov (United States)

    Faure, Pauline; Tanaka, Atomu; Cho, Mengu

    2017-04-01

    Lean satellite programs are programs in which the satellite development philosophy is driven by fast delivery and low cost. Though this concept offers the possibility to develop and fly risky missions without jeopardizing a space program, most of these satellites suffer infant mortality and fail to achieve their mission minimum success. Lean satellites with high infant mortality rate indicate that testing prior to launch is insufficient. In this study, the authors monitored failures occurring during the development of the lean satellite HORYU-IV to identify the evolution of the cumulative number of failures against cumulative testing time. Moreover, the sub-systems driving the failures depending on the different development phases were identified. The results showed that half to 2/3 of the failures are discovered during the early stage of testing. Moreover, when the mean time before failure was calculated, it appeared that for any development phase considered, a new failure appears on average every 20 h of testing. Simulations were also performed and it showed that for an initial testing time of 50 h, reliability after 1 month launch can be improved by nearly 6 times as compared to an initial testing time of 20 h. Through this work, the authors aim at providing a qualitative reference for lean satellites developers to better help them manage resources to develop lean satellites following a fast delivery and low cost philosophy while ensuring sufficient reliability to achieve mission minimum success.

  19. TOLNET – A Tropospheric Ozone Lidar Profiling Network for Satellite Continuity and Process Studies

    Directory of Open Access Journals (Sweden)

    Newchurch Michael J.

    2016-01-01

    Full Text Available Ozone lidars measure continuous, high-resolution ozone profiles critical for process studies and for satellite validation in the lower troposphere. However, the effectiveness of lidar validation by using single-station data is limited. Recently, NASA initiated an interagency ozone lidar observation network under the name TOLNet to promote cooperative multiple-station ozone-lidar observations to provide highly timeresolved (few minutes tropospheric-ozone vertical profiles useful for air-quality studies, model evaluation, and satellite validation. This article briefly describes the concept, stations, major specifications of the TOLNet instruments, and data archiving.

  20. 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 ...

  1. Bibliometric study of the reverse salient concept

    Directory of Open Access Journals (Sweden)

    Ozgur Dedehayir

    2009-12-01

    Full Text Available In the development of technological systems the focus of system analysis is often on the sub-system that delivers insufficient performance – i.e. the reverse salient – which subsequently limits the performance of the system in its entirety. The reverse salient is therefore a useful concept in the study of technological systems and while the literature holds numerous accounts of its use, it is not known how often, in which streams of literature, and in what type of application the concept has been utilized by scholars since its introduction by Thomas Hughes in 1983. In this paper we employ bibliometric citation analysis between 1983 and 2008, inclusively, to study the impact of the reverse salient concept in the literature at large as well as study the dissemination of the concept into different fields of research. The study results show continuously growing number of concept citations in the literature over time as well as increasing concept diffusion into different research areas. The analysis of article contents additionally suggests the opportunity for scholars to engage in deeper conceptual application. Finally, the continuing increase in the number of citations highlights the importance of the reverse salient concept to scholars and practitioners.

  2. NASA's Gravitational - Wave Mission Concept Study

    Science.gov (United States)

    Stebbins, Robin; Jennrich, Oliver; McNamara, Paul

    2012-01-01

    With the conclusion of the NASA/ESA partnership on the Laser Interferometer Space Antenna (LISA) Project, NASA initiated a study to explore mission concepts that will accomplish some or all of the LISA science objectives at lower cost. The Gravitational-Wave Mission Concept Study consisted of a public Request for Information (RFI), a Core Team of NASA engineers and scientists, a Community Science Team, a Science Task Force, and an open workshop. The RFI yielded were 12 mission concepts, 3 instrument concepts and 2 technologies. The responses ranged from concepts that eliminated the drag-free test mass of LISA to concepts that replace the test mass with an atom interferometer. The Core Team reviewed the noise budgets and sensitivity curves, the payload and spacecraft designs and requirements, orbits and trajectories and technical readiness and risk. The Science Task Force assessed the science performance by calculating the horizons. the detection rates and the accuracy of astrophysical parameter estimation for massive black hole mergers, stellar-mass compact objects inspiraling into central engines. and close compact binary systems. Three mission concepts have been studied by Team-X, JPL's concurrent design facility. to define a conceptual design evaluate kt,y performance parameters. assess risk and estimate cost and schedule. The Study results are summarized.

  3. Key Concepts in Family Studies

    OpenAIRE

    Ribbens McCarthy, Jane; Edwards, Rosalind

    2011-01-01

    Taken from the book to be published by Sage in December 2010, this document provides the Introduction to the book, in which the authors discuss issues in Family Studies as a contemporary field of academic and professional work. Their discussion includes: some of the different positions adopted by researchers towards the use of the language of 'family'; the broad themes generally included in this field of study; and dilemmas in evaluations of, and interventions in, family lives.\\ud

  4. 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.

  5. 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

  6. Maritime Patrol Airship Concept Study

    Science.gov (United States)

    1978-11-16

    study additional applications of the company’s ACV technology, the Navy and the Commerce Department’s Maritime Ad- I. r . r lands abn,’ ,--r- t• LA... Voyageur , were proviug the potential of versatile, Patdeck ACVs for a wide range of future .k,, applications. By 1975, Voyageurs w-re at work with the...engineering in Canada’s Ministry of Transport, explained that the Voyageur was traveling at abott 15 knots over hard, unbroken ice when the crew noticed

  7. The EXIST Mission Concept Study

    Science.gov (United States)

    Fishman, Gerald J.; Grindlay, J.; Hong, J.

    2008-01-01

    EXIST is a mission designed to find and study black holes (BHs) over a wide range of environments and masses, including: 1) BHs accreting from binary companions or dense molecular clouds throughout our Galaxy and the Local Group, 2) supermassive black holes (SMBHs) lying dormant in galaxies that reveal their existence by disrupting passing stars, and 3) SMBHs that are hidden from our view at lower energies due to obscuration by the gas that they accrete. 4) the birth of stellar mass BHs which is accompanied by long cosmic gamma-ray bursts (GRBs) which are seen several times a day and may be associated with the earliest stars to form in the Universe. EXIST will provide an order of magnitude increase in sensitivity and angular resolution as well as greater spectral resolution and bandwidth compared with earlier hard X-ray survey telescopes. With an onboard optical-infra red (IR) telescope, EXIST will measure the spectra and redshifts of GRBs and their utility as cosmological probes of the highest z universe and epoch of reionization. The mission would retain its primary goal of being the Black Hole Finder Probe in the Beyond Einstein Program. However, the new design for EXIST proposed to be studied here represents a significant advance from its previous incarnation as presented to BEPAC. The mission is now less than half the total mass, would be launched on the smallest EELV available (Atlas V-401) for a Medium Class mission, and most importantly includes a two-telescope complement that is ideally suited for the study of both obscured and very distant BHs. EXIST retains its very wide field hard X-ray imaging High Energy Telescope (HET) as the primary instrument, now with improved angular and spectral resolution, and in a more compact payload that allows occasional rapid slews for immediate optical/IR imaging and spectra of GRBs and AGN as well as enhanced hard X-ray spectra and timing with pointed observations. The mission would conduct a 2 year full sky survey in

  8. The Core Journal Concept in Black Studies

    Science.gov (United States)

    Weissinger, Thomas

    2010-01-01

    Black Studies scholars have shown interest in the core journal concept. Indeed, the idea of core journals for the study of the Black experience has changed several times since 1940. While Black Studies scholars are citing Black Studies journals with frequency, they also cite traditional disciplinary journals a great deal of the time. However,…

  9. A comparative study of satellite and ground-based phenology.

    Science.gov (United States)

    Studer, S; Stöckli, R; Appenzeller, C; Vidale, P L

    2007-05-01

    Long time series of ground-based plant phenology, as well as more than two decades of satellite-derived phenological metrics, are currently available to assess the impacts of climate variability and trends on terrestrial vegetation. Traditional plant phenology provides very accurate information on individual plant species, but with limited spatial coverage. Satellite phenology allows monitoring of terrestrial vegetation on a global scale and provides an integrative view at the landscape level. Linking the strengths of both methodologies has high potential value for climate impact studies. We compared a multispecies index from ground-observed spring phases with two types (maximum slope and threshold approach) of satellite-derived start-of-season (SOS) metrics. We focus on Switzerland from 1982 to 2001 and show that temporal and spatial variability of the multispecies index correspond well with the satellite-derived metrics. All phenological metrics correlate with temperature anomalies as expected. The slope approach proved to deviate strongly from the temporal development of the ground observations as well as from the threshold-defined SOS satellite measure. The slope spring indicator is considered to indicate a different stage in vegetation development and is therefore less suited as a SOS parameter for comparative studies in relation to ground-observed phenology. Satellite-derived metrics are, however, very susceptible to snow cover, and it is suggested that this snow cover should be better accounted for by the use of newer satellite sensors.

  10. Low-Cost Satellite Infrared Imager Study

    Science.gov (United States)

    2007-11-02

    2,297.00 10 MATLAB , Simulink , Symbolic Math Toolbox (2 ea @ £894) £1,788.00 11 MATLAB Image Processing Toolbox (2 ea at £192) £384.00 12 MATLAB ...Figure 1: MWIR and TIR satellite imagery. On the left is a BIRD image of forest fires on the Portuguese/ Spanish border3 and the image on right is...space-borne MWIR and TIR imagers, instrument engineers are continually evaluating advances in the miniaturization of detector technology. One

  11. Aerobrake concepts for NTP systems study

    Science.gov (United States)

    Cruz, Manuel I.

    1992-06-01

    Design concepts are described for landing large spacecraft masses on the Mars surface in support of manned missions with interplanetary transportation using Nuclear Thermal Propulsion (NTP). Included are the mission and systems analyses, trade studies and sensitivity analyses, design analyses, technology assessment, and derived requirements to support this concept. The mission phases include the Mars de-orbit, entry, terminal descent, and terminal touchdown. The study focuses primarily on Mars surface delivery from orbit after Mars orbit insertion using an NTP. The requirements associated with delivery of logistical supplies, habitats, and other equipment on minimum energy Earth to Mars transfers are also addressed in a preliminary fashion.

  12. 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).

  13. 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.

  14. Reusable Reentry Satellite (RRS) system design study

    Science.gov (United States)

    1991-01-01

    The Reusable Reentry Satellite (RRS) is intended to provide investigators in several biological disciplines with a relatively inexpensive method to access space for up to 60 days with eventual recovery on Earth. The RRS will permit totally intact, relatively soft, recovery of the vehicle, system refurbishment, and reflight with new and varied payloads. The RRS is to be capable of three reflights per year over a 10-year program lifetime. The RRS vehicle will have a large and readily accessible volume near the vehicle center of gravity for the Payload Module (PM) containing the experiment hardware. The vehicle is configured to permit the experimenter late access to the PM prior to launch and rapid access following recovery. The RRS will operate in one of two modes: (1) as a free-flying spacecraft in orbit, and will be allowed to drift in attitude to provide an acceleration environment of less than 10(exp -5) g. the acceleration environment during orbital trim maneuvers will be less than 10(exp -3) g; and (2) as an artificial gravity system which spins at controlled rates to provide an artificial gravity of up to 1.5 Earth g. The RRS system will be designed to be rugged, easily maintained, and economically refurbishable for the next flight. Some systems may be designed to be replaced rather than refurbished, if cost effective and capable of meeting the specified turnaround time. The minimum time between recovery and reflight will be approximately 60 days. The PMs will be designed to be relatively autonomous, with experiments that require few commands and limited telemetry. Mass data storage will be accommodated in the PM. The hardware development and implementation phase is currently expected to start in 1991 with a first launch in late 1993.

  15. 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.

  16. Study of LEO-SAT microwave link for broad-band mobile satellite communication system

    Science.gov (United States)

    Fujise, Masayuki; Chujo, Wataru; Chiba, Isamu; Furuhama, Yoji; Kawabata, Kazuaki; Konishi, Yoshihiko

    1993-01-01

    In the field of mobile satellite communications, a system based on low-earth-orbit satellites (LEO-SAT's) such as the Iridium system has been proposed. The LEO-SAT system is able to offer mobile telecommunication services in high-latitude areas. Rain degradation, fading and shadowing are also expected to be decreased when the system is operated at a high elevation angle. Furthermore, the propagation delay generated in the LEO-SAT system is less pronounced than that in the geostationary orbit satellite (GEO-SAT) system and, in voice services, the effect of the delay is almost negligible. We proposed a concept of a broad-band mobile satellite communication system with LEO-SAT's and Optical ISL. In that system, a fixed L-band (1.6/1.5 GHz) multibeam is used to offer narrow band service to the mobile terminals in the entire area covered by a LEO-SAT and steerable Ka-band (30/20 GHz) spot beams are used for the wide band service. In this paper, we present results of a study of LEO-SAT microwave link between a satellite and a mobile terminal for a broad-band mobile satellite communication system. First, the results of link budget calculations are presented and the antennas mounted on satellites are shown. For a future mobile antenna technology, we also show digital beamforming (DBF) techniques. DBF, together with modulation and/or demodulation, is becoming a key technique for mobile antennas with advanced functions such as antenna pattern calibration, correction, and radio interference suppression. In this paper, efficient DBF techniques for transmitting and receiving are presented. Furthermore, an adaptive array antenna system suitable for this LEO-SAT is presented.

  17. '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

  18. Study on relative orbital configuration in satellite formation flying

    Institute of Scientific and Technical Information of China (English)

    Junfeng Li; Xin Meng; Yunfeng Gao; Xiang Li

    2005-01-01

    In this paper, the relative orbital configurations of satellites in formation flying with non-perturbation and J2 perturbation are studied, and an orbital elements method is proposed to obtain the relative orbital configurations of satellites in formation. Firstly, under the condition of nonperturbation, we obtain many shapes of relative orbital configurations when the semi-major axes of satellites are equal.These shapes can be lines, ellipses or distorted closed curves.Secondly, on the basis of the analysis of J2 effect on relative orbital configurations, we find out that J2 effect can induce two kinds of changes of relative orbital configurations. They are distortion and drifting, respectively. In addition, when J2perturbation is concerned, we also find that the semi-major axes of the leading and following satellites should not be the same exactly in order to decrease the J2 effect. The relationship of relative orbital elements and J2 effect is obtained through simulations. Finally, the minimum relation perturbation conditions are established in order to reduce the influence of the J2 effect. The results show that the minimum relation perturbation conditions can reduce the J2 effect significantly when the orbital element differences are small enough, and they can become rules for the design of satellite formation flying.

  19. Study Sequence Matters for the Inductive Learning of Cognitive Concepts

    Science.gov (United States)

    Sana, Faria; Yan, Veronica X.; Kim, Joseph A.

    2017-01-01

    The sequence in which problems of different concepts are studied during instruction impacts concept learning. For example, several problems of a given concept can be studied together (blocking) or several problems of different concepts can be studied together (interleaving). In the current study, we demonstrate that the 2 sequences impact concept…

  20. 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…

  1. Space Station concept development group studies

    Science.gov (United States)

    Powell, L. E.

    1984-01-01

    The NASA study activities in preparation for a Space Station began in the early 1970's. The early studies included many in-house NASA and contracted studies. A group of representatives from all the NASA Centers, titled the Space Station Concept Development Group (CDG) was involved in the studies which led to the initiation of the Space Station Program. The CDG studies were performed over a period of approximately one year and consisted of four phases. The initial phase had the objective to determine the functions required of the station as opposed to a configuration. The activities of the second phase were primarily concerned with a sizing of the facilities required for payloads and the resources necessary to support these mission payloads. The third phase of studies was designed to develop a philosophical approach to a number of areas related to autonomy, maintainability, operations and logistics, and verification. The fourth phase of the study was to be concerned with configuration assessment activities.

  2. Identifying Threshold Concepts for Information Literacy: A Delphi Study

    Directory of Open Access Journals (Sweden)

    Lori Townsend

    2016-06-01

    Full Text Available This study used the Delphi method to engage expert practitioners on the topic of threshold concepts for information literacy. A panel of experts considered two questions. First, is the threshold concept approach useful for information literacy instruction? The panel unanimously agreed that the threshold concept approach holds potential for information literacy instruction. Second, what are the threshold concepts for information literacy instruction? The panel proposed and discussed over fifty potential threshold concepts, finally settling on six information literacy threshold concepts.

  3. Using Satellite Imagery to Study Landslides

    Science.gov (United States)

    Reif, S. L.; Bluth, G. J.; Rose, W. I.; Matias, O.; Wolf, R.

    2003-04-01

    Much of the world's population currently lives under the threat of volcanic hazards in the secondary form of debris movements such as landslides and lahars. Remote sensing is becoming a useful tool for hazard studies, yet many hazard-prone areas do not utilize this important resource. In this project, we intend to use common remote sensing techniques to study characteristics of landslides and lahars in order to predict hazard zones. Fuego Volcano in Guatemala is a steep sided volcano with a history of large eruptive events, including the well-studied 1974 eruption, that have extruded a large amount of material onto the upper reaches of the Fuego watersheds. Eruption processes have been a primary focus of studies; however, remobilization during the rainy season of the erupted material is hazardous to the local population and agriculture (Vallance et al. 2001, USGS Open-File Report 01-431). A study of the way material moves down Fuego and to the extent that it moves is needed to help properly mitigate the potential hazards. We propose an in-depth remote sensing survey to map the hazard-prone areas. The study will consist of processing 20 years (15 cloud-free images) of Landsat TM and ETM+ data to look at changes in landforms and vegetation. Vegetation indices will be calculated to locate areas devoid of vegetation and a masking process will be used to measure the area of these zones. These area changes will be related to field measurements to create GIS layers denoting geometry changes in the channels around Fuego. These changes will be loaded into a GIS, along with regional climate data, DEMs, hydrologic data, infrastructure, and information about the known volcanic activity recorded in the area by the local volcanologists. Modeling of lahars using LAHARZ and climate data will also be done to determine an estimate of the amount of material moved and to what distances it can be transported. A field survey undertaken in January 2003 acquired GPS ground truth data of

  4. Gravimetric geodesy and sea surface topography studies by means of satellite-to-satellite tracking and satellite altimetry

    Science.gov (United States)

    Siry, J. W.

    1972-01-01

    A satellite-to-satellite tracking experiment is planned between ATS-F and GEOS-C with a range accuracy of 2-meters and a range rate accuracy of 0.035 centimeters per second for a 10-second integration time. This experiment is planned for 1974. It is anticipated that it will improve the spatial resolution of the satellite geoid by half an order of magnitude to about 6 degrees. Longer integration times should also permit a modest increase in the acceleration resolution. Satellite altimeter data will also be obtained by means of GEOS-C. An overall accuracy of 5-meters in altitude is the goal. The altimeter, per se, is expected to have an instrumental precision of about 2 meters, and an additional capability to observe with a precision of about 0.2 meters for limited periods.

  5. The concept of body in religious studies

    Directory of Open Access Journals (Sweden)

    Matti Kamppinen

    2011-01-01

    Full Text Available Recently it has become fashionable to speak about embodied religion, religion as bodily processes and embodiment in general. In this article the different uses of the concept of the body are analysed and the different contexts in which the concept can be used in coherent and systematic ways are clarified, and furthermore in such a way that it enhances the methodology of religious studies. Bodies are relevant in religious studies first and foremost for the reason that some bodies support religious beliefs, desires and actions, such as priests in the Catholic Church or members of the organizations of charismatic Christianity. Secondly, bodies are ascribed religious meanings. That is, in addition to a human body x, we have one or more religious actors who ascribe religious meanings to this particular body. Even though bodily issues are important for biological creatures such as human beings, they are not relevant for religious studies if they do not involve secondary theories that attach religious contents to them.

  6. 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.

  7. Orbital rotations of a satellite. Case study: GOCE

    Science.gov (United States)

    Baur, O.; Grafarend, E. W.

    Considering a satellite orbit as a space curve in terms of Differential Geometry, we succeeded to merge orbital rotation and curvature/torsion by means of Cartan connection. Here we transform the Frenet frame of reference of the space curve to the Kepler frame of reference ("along track", "cross track", "quasi-radial") of the satellite orbit by means of Meusnier's Lemma. As a case study, we identify the spectrum of orbital rotation frequencies relative to a GOCE satellite configuration. In particular, we identify more than one rotational period. For a moving frame of reference of type Frenet, periods in the range of the time of revolution of the satellite as well as half the time of revolution appear, whereas even periods of a third the revolution time become visible for the Kepler frame of reference. We describe moving frame rotations with respect to the quasi-inertial frame of reference, namely the angular velocities around the base vectors, by means of curvature measures. This allows to calculate frame rotations by geometric orbit information only (GPS track), i.e. apart from gradiometer measurements. Among other things, we identify the angular velocity relative to the second base vector becoming strictly zero in case of the Frenet frame of reference.

  8. An Experimental Biotelemetric Study Based on Satellite Tracking During Post-nesting Migrations of Green Turtles

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A biotelemetry experiment is conducted to study the migrant behavior of green turtles (Chelonia mydas) in South China Sea and acquire the physical environment data. The method in use is to track the post-nesting migrant routes of green turtles through the satellite linked transmitters attached on the back of turtles and the global satellite signal transmitting system of Argos. We obtained the posinestions of the post-nesting migrant routes of three green turtles and environment data, which are important in conservation of green turtles and the research of physical oceanography. Based on the test, the concept, principle and method of biotelemetry are also introduced in this paper with a discussion of the further development of this technique and its applying prospection in future.

  9. Air Quality Study Using Satellites - Current Capability and Future Plans

    Science.gov (United States)

    Bhartia, Pawan K.; Joiner, Joanna; Gleason, James; Liu, Xiong; Torres, Omar; Krotkov, Nickolay; Ziemke, Jerry; Chandra, Sushil

    2008-01-01

    Satellite instruments have had great success in monitoring the stratospheric ozone and in understanding the processes that control its daily to decadal scale variations. This field is now reaching its zenith with a number of satellite instruments from the US, Europe and Canada capping several decades of active research in this field. The primary public policy imperative of this research was to make reliable prediction of increases in biologically active surface UV radiation due to human activity. By contrast retrieval from satellite data of atmospheric constituents and photo-chemically active radiation that affect air quality is a new and growing field that is presenting us with unique challenges in measurement and data interpretation. A key distinction compared to stratospheric sensors is the greatly enhanced role of clouds, aerosols, and surfaces (CAS) in determining the quality and quantity of useful data that is available for air quality research. In our presentation we will use data from several sensors that are currently flying on the A-train satellite constellation, including OMI, MODIS, CLOUDSAT, and CALIPSO, to highlight that CAS can have both positive and negative effects on the information content of satellite measurements. This is in sharp contrast to other fields of remote sensing where CAS are usually considered an interference except in those cases when they are the primary subject of study. Our analysis has revealed that in the reflected wavelengths one often sees much further down into the atmosphere, through most cirrus, than one does in the emitted wavelengths. The lower level clouds provide a nice background against which one can track long-range transport of trace gases and aerosols. In addition, differences in trace gas columns estimated over cloudy and adjacent clear pixels can be used to measure boundary layer trace gases. However, in order to take full advantage of these features it will be necessary to greatly advance our understanding of

  10. A Review of Solution Chemistry Studies: Insights into Students' Conceptions

    Science.gov (United States)

    Calyk, Muammer; Ayas, Alipa; Ebenezer, Jazlin V.

    2005-01-01

    This study has reviewed the last two decades of student conception research in solution chemistry pertaining to aims, methods of exploring students' conception, general knowledge claims, students' conceptions and difficulties, and conceptual change studies. The aims of solution chemistry studies have been to assess students' understanding level of…

  11. Personal Access Satellite System (PASS) study. Fiscal year 1989 results

    Science.gov (United States)

    Sue, Miles K. (Editor)

    1990-01-01

    The Jet Propulsion Laboratory is exploring the potential and feasibility of a personal access satellite system (PASS) that will offer the user greater freedom and mobility than existing or currently planned communications systems. Studies performed in prior years resulted in a strawman design and the identification of technologies that are critical to the successful implementation of PASS. The study efforts in FY-89 were directed towards alternative design options with the objective of either improving the system performance or alleviating the constraints on the user terminal. The various design options and system issues studied this year and the results of the study are presented.

  12. 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.

  13. 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.

  14. A study of multiple access schemes in satellite control network

    Science.gov (United States)

    Mo, Zijian; Wang, Zhonghai; Xiang, Xingyu; Wang, Gang; Chen, Genshe; Nguyen, Tien; Pham, Khanh; Blasch, Erik

    2016-05-01

    Satellite Control Networks (SCN) have provided launch control for space lift vehicles; tracking, telemetry and commanding (TTC) for on-orbit satellites; and, test support for space experiments since the 1960s. Currently, SCNs encounter a new challenge: how to maintain the high reliability of services when sharing the spectrum with emerging commercial services. To achieve this goal, the capability of multiple satellites reception is deserved as an update/modernization of SCN in the future. In this paper, we conducts an investigation of multiple access techniques in SCN scenario, e.g., frequency division multiple access (FDMA) and coded division multiple access (CDMA). First, we introduce two upgrade options of SCN based on FDMA and CDMA techniques. Correspondingly, we also provide their performance analysis, especially the system improvement in spectrum efficiency and interference mitigation. Finally, to determine the optimum upgrade option, this work uses CRISP, i.e., Cost, Risk, Installation, Supportability and Performance, as the baseline approach for a comprehensive trade study of these two options. Extensive numerical and simulation results are presented to illustrate the theoretical development.

  15. Simobiz-Simulation Tool to Study the Impact of Small Satellites in Mobile Market

    Science.gov (United States)

    Burlacu, M.-M.; Kohlenberg, J.; Prathaban, M.

    2008-08-01

    Interest in small satellites is growing fast world- wide. Businesses, governments, universities and other organizations around the world are starting their own small satellite programs. The surveys conducted by the space agencies and universities shows a promising increase in the use of small satellites for commercial applications. More number of operators offers or plans to offer mobile phone services by satellite. With the help of cost effective small satellite, mobile operators can be able to provide the services cheaper. Hence, it is always interesting to study the effect of low cost small satellite over the mobile market. In this article, we present SmartSim (Small Satellites Mobile Market Simulator) - the new module of Simobiz business simulation game, in which we have implemented two operators, a normal satellite operator and a nanosatellite operator, with specific terminals and services. Our main focus in this work is to understand the future market of small satellite in mobile telecommunication network.

  16. Parameter Studies for the VISTA Spacecraft Concept

    Energy Technology Data Exchange (ETDEWEB)

    Orth, C D

    2000-11-21

    The baseline design for the VISTA spacecraft concept employs a diode-pumped solid-state laser (DPSSL) driver. This type of driver is now under development at LLNL and elsewhere as an extension of the mature solid-state (glass) laser technology developed for terrestrial applications of inertial confinement fusion (ICF). A DPSSL is repratable up to at least 30 Hz, and has an efficiency soon to be experimentally verified of at least 10%. By using a detailed systems code including the essential physics of a DPSSL, we have run parameter studies for the baseline roundtrip (RT) to Mars with a 100-ton payload. We describe the results of these studies as a function of the optimized (minimum) RT flight duration. We also demonstrate why DT fuel gives the best performance, although DD, D3He, or even antimatter can be used, and why DT-ignited DD is probably the fuel most preferred. We also describe the overall power flow, showing where the fusion energy is ultimately utilized, and estimate the variation in performance to the planets dictated by variations in target gain and other parameters.

  17. Photometric Studies of Rapidly Spinning Decommissioned GEO Satellites

    Science.gov (United States)

    Ryan, W.; Ryan, E.

    A satellites general characteristics can be substantially influenced by changes in the space environment. Rapidly spinning decommissioned satellites provide an excellent opportunity to study the rotation-dependent physical processes that affect a resident space objects (RSO) spin kinematics over time. Specifically, inactive satellites at or near geosynchronous Earth-orbit (GEO) provide easy targets for which high quality data can be collected and analyzed such that small differences can be detected under single-year or less time frames. Previous workers have shown that the rotational periods of defunct GEOs have been changing over time [1]. Further, the Yarkovsky-OKeefe-Radzievskii-Paddak (YORP) effect, a phenomenon which has been well-studied in the context of the changing the spin states of asteroids, has recently been suggested to be the cause of secular alterations in the rotational period of inactive satellites [2]. Researchers at the Magdalena Ridge Observatory 2.4-meter telescope (operated by the New Mexico Institute of Mining and Technology) have been investigating the spins states of retired GEOs and other high altitude space debris since 2007 [3]. In this current work, the 2.4-meter telescope was used to track and observe the objects typically over a one- to two-hour period, repeated several times over the course of weeks. When feasible, this is then repeated on a yearly basis. Data is taken with a 1 second cadence, nominally in groups of three 600 second image sets. With the current equipment, the cadence of the image sequences is very precise while the start time is accurate only to the nearest second. Therefore, periods are determined individually using each image sequence. Repeatability of the period determination for each of these sequences is typically on the order of 0.01 second or better for objects where a single period is identified. Spin rate periods determined from the GEO light curves collected thus far have been found to range from ~3 sec to

  18. Learning from Concept Mapping and Hypertext: An Eye Tracking Study

    Science.gov (United States)

    Amadieu, Franck; Salmerón, Ladislao; Cegarra, Julien; Paubel, Pierre-Vincent; Lemarié, Julie; Chevalier, Aline

    2015-01-01

    This study examined the effects of prior domain knowledge and learning sequences on learning with concept mapping and hypertext. Participants either made a concept map in a first step and then read the hypertext's contents combined with concept mapping (high activating condition), or they read the hypertext's contents first and then made a concept…

  19. 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.

  20. A Comparative Study of Actuator Configurations for Satellite Attitude Control

    Directory of Open Access Journals (Sweden)

    Raymond Kristiansen

    2005-10-01

    Full Text Available In this paper a controllability study of different actuator configurations consisting of magnetic torquers, reaction wheels and a gravity boom is presented. The theoretical analysis is performed with use of controllability gramians, and simulation results with the different configurations are presented and compared regarding settling time and power consumption to substantiate the theoretical analysis. A reference model is also introduced to show how the power consumption can he lowered to the same magnitude as when magnetic torquers are used, without degrading the satellite response significantly.

  1. Politicizing science: conceptions of politics in science and technology studies.

    Science.gov (United States)

    Brown, Mark B

    2015-02-01

    This essay examines five ideal-typical conceptions of politics in science and technology studies. Rather than evaluating these conceptions with reference to a single standard, the essay shows how different conceptions of politics serve distinct purposes: normative critique, two approaches to empirical description, and two views of democracy. I discuss each conception of politics with respect to how well it fulfills its apparent primary purpose, as well as its implications for the purpose of studying a key issue in contemporary democratic societies: the politicization of science. In this respect, the essay goes beyond classifying different conceptions of politics and also recommends the fifth conception as especially conducive to understanding and shaping the processes whereby science becomes a site or object of political activity. The essay also employs several analytical distinctions to help clarify the differences among conceptions of politics: between science as 'political' (adjective) and science as a site of 'politics' (noun), between spatial-conceptions and activity-conceptions of politics, between latent conflicts and actual conflicts, and between politics and power. The essay also makes the methodological argument that the politics of science and technology is best studied with concepts and methods that facilitate dialogue between actors and analysts. The main goal, however, is not to defend a particular view of politics, but to promote conversation on the conceptions of politics that animate research in social studies of science and technology.

  2. Study on feasibility of laser reflective tomography with satellite-accompany

    Science.gov (United States)

    Gu, Yu; Hu, Yi-hua; Hao, Shi-qi; Gu, You-lin; Zhao, Nan-xiang; Wang, Yang-yang

    2015-10-01

    Laser reflective tomography is a long-range, high-resolution active detection technology, whose advantage is that the spatial resolution is unrelated with the imaging distance. Accompany satellite is a specific satellite around the target spacecraft with encircling movement. When using the accompany satellite to detect the target aircraft, multi-angle echo data can be obtained with the application of reflective tomography imaging. The feasibility of such detection working mode was studied in this article. Accompany orbit model was established with horizontal circular fleet and the parameters of accompany flight was defined. The simulation of satellite-to-satellite reflective tomography imaging with satellite-accompany was carried out. The operating mode of reflective tomographic data acquisition from monostatic laser radar was discussed and designed. The flight period, which equals to the all direction received data consuming time, is one of the important accompany flight parameters. The azimuth angle determines the plane of image formation while the elevation angle determines the projection direction. Both of the azimuth and elevation angles guide the satellite attitude stability controller in order to point the laser radar spot on the target. The influences of distance between accompany satellite and target satellite on tomographic imaging consuming time was analyzed. The influences of flight period, azimuth angle and elevation angle on tomographic imaging were analyzed as well. Simulation results showed that the satellite-accompany laser reflective tomography is a feasible and effective method to the satellite-to-satellite detection.

  3. Mars power system concept definition study. Volume 1: Study results

    Science.gov (United States)

    Littman, Franklin D.

    1994-12-01

    A preliminary top level study was completed to define power system concepts applicable to Mars surface applications. This effort included definition of power system requirements and selection of power systems with the potential for high commonality. These power systems included dynamic isotope, Proton Exchange Membrane (PEM) regenerative fuel cell, sodium sulfur battery, photovoltaic, and reactor concepts. Design influencing factors were identified. Characterization studies were then done for each concept to determine system performance, size/volume, and mass. Operations studies were done to determine emplacement/deployment maintenance/servicing, and startup/shutdown requirements. Technology development roadmaps were written for each candidate power system (included in Volume 2). Example power system architectures were defined and compared on a mass basis. The dynamic isotope power system and nuclear reactor power system architectures had significantly lower total masses than the photovoltaic system architectures. Integrated development and deployment time phasing plans were completed for an example DIPS and reactor architecture option to determine the development strategies required to meet the mission scenario requirements.

  4. Feasability Study of Electronic Load Sensing Concept

    DEFF Research Database (Denmark)

    Hansen, Michael Rygaard; Andersen, Torben O.; Pedersen, Henrik C.

    2006-01-01

    to traditional LS-systems, in terms of better control and system utilization possibilities, combined with the increased acceptance and use of electronic sensors in mobile hydraulic machinery. The current work is to evaluate the suitability of an ELS concepts applied to a Sauer Danfoss Series 45 H-frame open......Electronic load sensing (ELS) systems have long been expected to start replacing traditional (hydro-mechanical) load sensing (LS) systems, which today are the standard on most medium and high-end mobile hydraulic applications. The reason for this being the potentials that ELS brings relative...

  5. Assessment of Satellite Images for Soil Salinity Studies

    Directory of Open Access Journals (Sweden)

    S.H. Sanaeinejad

    2012-04-01

    Full Text Available Soil salinity is one of the main environmental problems affecting extensive area in the world. There are some problems with traditional data collection methods for soil studies. Using the new methods and techniques such as remote sensing could overcome most of these problems. However using these data in areas with uncommon usages needed some researches to find the best calibration between the data and real situations in soil. This research was carried out using Landsat satellite images in Neyshabour area, North East of Iran. In order to prepare suitable learning samples for the image processing in this study, 300 locations were randomly selected in the area, among which 273 locations were finally selected as suitable surface soil samples. All samples were moved to laboratory and their electrical conductivity was measured. Six reflective bands of ETM+ satellite images taken from the study area in 2002 were used for the image processing analysis. Classification of different soil salinities was carried out using common algorithms of image classification based on the best composition bands and using statistical methods between soil salinity variables and digital numbers of the images to represent a suitable method. the research results showed that the reflective bands 7, 3, 4 and 1 are the best band composition for preparing the color composite images and for the classification of the salinity in this area. The highest coefficient of determination was R2=0.311 and R2=0.44 for saline and non-saline soil respectively using band 2 and 3 of the images at 5% significant level. Based on the results, it can be concluded that the potential of ETM+ images for delineation and identification of different soil salinity are limited.

  6. Study on the applicability of the desk replacement ventilation concept

    NARCIS (Netherlands)

    Loomans, M.G.L.C.

    1999-01-01

    This paper summarizes an experimental and numerical study into a ventilation concept that combines displacement ventilation with task conditioning, the so-called desk displace-ment ventilation (DDV) concept. The study uses steady-state and transient results to discuss the applicability of the DDV co

  7. Study on the applicability of the desk displacement ventilation concept

    NARCIS (Netherlands)

    Loomans, Marcel G.L.C.

    1999-01-01

    This paper summarizes an experimental and numerical study into a ventilation concept that combines displacement ventilation with task conditioning, the so-called desk displacement ventilation (DDV) concept. The study uses steady-state and transient results to discuss the applicability of the DDV con

  8. Study of novel concepts of power transmission gears

    Science.gov (United States)

    Rivin, Eugene I.

    1991-01-01

    Two concepts in power transmission gear design are proposed which provide a potential for large noise reduction and for improving weight to payload ratio due to use of advanced fiber reinforced and ceramic materials. These concepts are briefly discussed. Since both concepts use ultrathin layered rubber-metal laminates for accommodating limited travel displacements, properties of the laminates, such as their compressive strength, compressive and shear moduli were studied. Extensive testing and computational analysis were performed on the first concept gears (laminate coated conformal gears). Design and testing of the second conceptual design (composite gear with separation of sliding and rolling motions) are specifically described.

  9. Study on fault locating technology for satellite power system

    Institute of Scientific and Technical Information of China (English)

    LONG Bing; JIANG Xing-wei; SONG Zheng-ji

    2005-01-01

    It is currently prevalent to locate faults for a satellite power system based on an expert system, not utilizing all the available information provided by tests. The casual network model for a satellite power system is presented. Considerations for failure probability of each component of the power system, the cost of applying each test, the influence of a precedent test result on the next test selection, and an optimal sequential testing algorithm for fault location is presented. This program is applied to locate the failure component of the power system of a satellite. The results show this program is very effective and it is very fast to generate an optimal diagnosis tree.

  10. Next generation communications satellites: multiple access and network studies

    Science.gov (United States)

    Meadows, H. E.; Schwartz, M.; Stern, T. E.; Ganguly, S.; Kraimeche, B.; Matsuo, K.; Gopal, I.

    1982-01-01

    Efficient resource allocation and network design for satellite systems serving heterogeneous user populations with large numbers of small direct-to-user Earth stations are discussed. Focus is on TDMA systems involving a high degree of frequency reuse by means of satellite-switched multiple beams (SSMB) with varying degrees of onboard processing. Algorithms for the efficient utilization of the satellite resources were developed. The effect of skewed traffic, overlapping beams and batched arrivals in packet-switched SSMB systems, integration of stream and bursty traffic, and optimal circuit scheduling in SSMB systems: performance bounds and computational complexity are discussed.

  11. Study on Service Level Management in Integrated Satellite Information Network

    Institute of Scientific and Technical Information of China (English)

    SHANG Rui-qiang; ZHAO Jian-li; WANG Guang-xing

    2005-01-01

    Integrated Satellite Information Network (ISIN) includes those nodes in space and those on ground. It is the way to realize the fusion of satellite communication and traditional network technology. A satellite network management system based on Multiplex Network Management Protocol (MNMP) has accomplished traditional management, such as configuration, performance and fault management. An architecture of Service Level Management (SLM) in ISIN is proposed, and a service topology management and Service Level Agreement (SLA) are deeply researched. At last, service security and fault management are briefly discussed, and a simulation system is accomplished.

  12. Some antecedents of academic self-concept: a longitudinal study.

    Science.gov (United States)

    Chapman, J W; Lambourne, R; Silva, P A

    1990-06-01

    The influence of cognitive, achievement, and family background variables on academic self-concept was examined for 435 students participating in a major longitudinal study in New Zealand. Family background variables included mother's marital status at the birth of the child, family socio-economic status at the time the child was born, and family environment when the child was 7 years and 9 years of age. These factors were not significantly related to academic self-concept at ages 9 and 11. In addition, the general emotional status of mothers when their child was 3 years and 5 years old was not significantly related to academic self-concept at ages 9 and 11. Mother's intelligence when the child was 3 years, and mother's expectations for school performance when the child started school at age 5 were not significantly related to academic self-concept. Similarly, cognitive and intellectual functioning at ages 3, 5, 7, and 9 years were not significantly related to academic self-concept at ages 7 and 9 years. Rather, academic self-concept at age 11 appeared to be influenced primarily by reading achievement and academic self-concept at age 9, and academic self-concept at age 9 was influenced primarily by reading achievement at age 7. It was concluded that academic self-concept is mainly a product of school achievement, and that any influence home background factors may have are likely to occur by means of their effect on school achievement.

  13. Use of charging control guidelines for geosynchronous satellite design studies

    Science.gov (United States)

    Steves, N. J.

    1980-01-01

    Several of the principle guidelines from the Spacecraft Charging Design Guidelines Handbook are presented with illustrative examples. Use of the geomagnetic substorm specification to qualify satellite designs, the evaluation of satellite designs by using analytical modelling techniques, the use of selected materials and coatings to minimize charging, the tying of all conducting elements to a common ground, and the use of electrical filtering to protect circuits from discharge induced upsets are discussed. Discharge criteria and SCATHA data are excluded.

  14. Study of Some Strategies for Disposal of the GNSS Satellites

    Directory of Open Access Journals (Sweden)

    Diogo Merguizo Sanchez

    2015-01-01

    Full Text Available The complexity of the GNSS and the several types of satellites in the MEO region turns the creation of a definitive strategy to dispose the satellites of this system into a hard task. Each constellation of the system adopts its own disposal strategy; for example, in the American GPS, the disposal strategy consists in changing the altitude of the nonoperational satellites to 500 km above or below their nominal orbits. In this work, we propose simple but efficient techniques to discard satellites of the GNSS by exploiting Hohmann type maneuvers combined with the use of the 2ω˙+Ω˙≈0 resonance to increase its orbital eccentricity, thus promoting atmospheric reentry. The results are shown in terms of the increment of velocity required to transfer the satellites to the new orbits. Some comparisons with direct disposal maneuvers (Hohmann type are also presented. We use the exact equations of motion, considering the perturbations of the Sun, the Moon, and the solar radiation pressure. The geopotential model was considered up to order and degree eight. We showed the quantitative influence of the sun and the moon on the orbit of these satellites by using the method of the integral of the forces over the time.

  15. Study of the NWC electrons belt observed on DEMETER Satellite

    CERN Document Server

    Li, Xinqiao; Wang, Ping; Wang, Huanyu; Lu, Hong; Zhang, Xuemin; Huang, Jianping; Shi, Feng; Yu, Xiaoxia; Xu, Yanbing; Meng, Xiangcheng; Wang, Hui; Zhao, Xiaoyun; Parrot, M

    2010-01-01

    We analyzed the data from 2007 to 2008, which is observed by IDP onboard DEMETER satellite, during ten months of NWC working and seven months of NWC shutdown. The characteristic of the space instantaneous electron belts, which come from the influence of the VLF transmitted by NWC, is studied comprehensively. The main distribution region of the NWC electron belts and the flux change are given. We also studied the distribution characteristic of the average energy spectrum in different magnetic shell at the height of DEMETER orbit and the difference of the average energy spectrum of the electrons in the drift loss-cone between day and night. As a result, the powerful power of NWC transmitter and the 19.8 kHz narrow bandwidth VLF emission not only created a momentary electrons enhancement region, which strides 180 degree in them longitude direction and from 1.6 to 1.9 in L value, with the rise of the electrons flux reaching to 3 orders of magnitude mostly, but also induced the enhancement or loss of electrons in ...

  16. Feasibility study of a solar power satellite system configured by formation flying

    Energy Technology Data Exchange (ETDEWEB)

    Takeichi, Noboru; Ueno, Hiroshi; Oda, Mitsushige [Japan Aerospace Exploration Agency (JAXA), Inst. of Space Technology and Aeronautics, Tsukuba, Ibaraki (Japan)

    2005-11-15

    This paper presents a new concept of a solar power satellite system configured by formation flying. In this concept, the solar power satellite system consists of sunlight reflectors and an energy generator-transmitter. The energy generator- transmitter is on a common GEO, and the reflectors are placed on the north and south by using solar pressure to raise their orbits from GEO. Therefore, the orbits of the reflectors and that of the energy generator-transmitter make three parallel GEOs. The feasibility of the concept and its requirements are also discussed, focusing on the orbital and attitude mechanics of the reflector. Because the tilt angle of the sunlight changes with the turning of the seasons, it is sometimes necessary to raise the orbit by thrusters especially around the solstice. For attitude dynamics, spin stabilization and thruster control are discussed as the attitude control strategies against the gravity gradient torque, which acts as a persistent periodic disturbance. (Author)

  17. Satellite-Based Study of Glaciers Retreat in Northern Pakistan

    Science.gov (United States)

    Munir, Siraj

    Glaciers serve as a natural regulator of regional water supplies. About 16933 Km 2 area of glaciers is covered by Pakistan. These glaciers are enormous reservoirs of fresh water and their meltwater is an important resource which feed rivers in Pakistan. Glacier depletion, especially recent melting can affect agriculture, drinking water supplies, hydro-electric power, and ecological habitats. This can also have a more immediate impact on Pakistan's economy that depends mainly on water from glacier melt. Melting of seasonal snowfall and permanent glaciers has resulted not only in reduction of water resources but also caused flash floods in many areas of Pakistan. With the advent of satellite technology, using optical and SAR data the study of glaciers, has become possible. Using temporal data, based on calculation of snow index, band ratios and texture reflectance it has been revealed that the rate of glacier melting has increased as a consequent of global warming. Comparison of Landsat images of Batura glacier for October 1992 and October 2000 has revealed that there is a decrease of about 17 sq km in Batura glaciers. Although accurate changes in glacier extent cannot be assessed without baseline information, these efforts have been made to analyze future changes in glaciated area.

  18. Study of Remote Globular Cluster Satellites of M87

    Science.gov (United States)

    Sahai, Arushi; Shao, Andrew; Toloba, Elisa; Guhathakurta, Puragra; Peng, Eric W.; Zhang, Hao

    2017-01-01

    We present a sample of “orphan” globular clusters (GCs) with previously unknown parent galaxies, which we determine to be remote satellites of M87, a massive elliptical galaxy at the center of the Virgo Cluster of Galaxies. Because GCs were formed in the early universe along with their original parent galaxies, which were cannibalized by massive galaxies such as M87, they share similar age and chemical properties. In this study, we first confirm that M87 is the adoptive parent galaxy of our orphan GCs using photometric and spectroscopic data to analyze spatial and velocity distributions. Next, we increase the signal-to-noise ratio of our samples’ spectra through a process known as coaddition. We utilize spectroscopic absorption lines to determine the age and metallicity of our orphan GCs through comparison to stellar population synthesis models, which we then relate to the GCs’ original parent galaxies using a mass-metallicity relation. Our finding that remote GCs of M87 likely developed in galaxies with ~1010 solar masses implies that M87’s outer halo is formed of relatively massive galaxies, serving as important parameters for developing theories about the formation and evolution of massive galaxies.This research was funded in part by NASA/STScI and the National Science Foundation. Most of this work was carried out by high school students working under the auspices of the Science Internship Program at UC Santa Cruz.

  19. Nutrient disequilibria in agroecosystems: concepts and case studies

    NARCIS (Netherlands)

    Smaling, E.M.A.; Oenema, O.; Fresco, L.O.

    1999-01-01

    The stocks and flows of carbon and nutrients in the terrestrial and marine agroecosystems within the environment are discussed, and the latest concepts on the causes of nutrient imbalances are considered. Case studies are presented.

  20. Mapping Future Education and Training: Group Concept Mapping Study

    NARCIS (Netherlands)

    Stoyanov, Slavi; Hoogveld, Bert; Kirschner, Paul A.

    2010-01-01

    Stoyanov, S., Hoogveld, A. W. M., & Kirschner, P. A. (2010). Mapping Future Education and Training: Group Concept Mapping Study. Heerlen, The Netherlands: Open University of the Netherlands; EU Forlic project.

  1. Mapping Future Education and Training: Group Concept Mapping Study

    NARCIS (Netherlands)

    Stoyanov, Slavi; Hoogveld, Bert; Kirschner, Paul A.

    2010-01-01

    Stoyanov, S., Hoogveld, A. W. M., & Kirschner, P. A. (2010). Mapping Future Education and Training: Group Concept Mapping Study. Heerlen, The Netherlands: Open University of the Netherlands; EU Forlic project.

  2. Nutrient disequilibria in agroecosystems: concepts and case studies

    NARCIS (Netherlands)

    Smaling, E.M.A.; Oenema, O.; Fresco, L.O.

    1999-01-01

    The stocks and flows of carbon and nutrients in the terrestrial and marine agroecosystems within the environment are discussed, and the latest concepts on the causes of nutrient imbalances are considered. Case studies are presented.

  3. Exoplanet Yield Estimation for Decadal Study Concepts using EXOSIMS

    Science.gov (United States)

    Morgan, Rhonda; Lowrance, Patrick; Savransky, Dmitry; Garrett, Daniel

    2016-01-01

    The anticipated upcoming large mission study concepts for the direct imaging of exo-earths present an exciting opportunity for exoplanet discovery and characterization. While these telescope concepts would also be capable of conducting a broad range of astrophysical investigations, the most difficult technology challenges are driven by the requirements for imaging exo-earths. The exoplanet science yield for these mission concepts will drive design trades and mission concept comparisons.To assist in these trade studies, the Exoplanet Exploration Program Office (ExEP) is developing a yield estimation tool that emphasizes transparency and consistent comparison of various design concepts. The tool will provide a parametric estimate of science yield of various mission concepts using contrast curves from physics-based model codes and Monte Carlo simulations of design reference missions using realistic constraints, such as solar avoidance angles, the observatory orbit, propulsion limitations of star shades, the accessibility of candidate targets, local and background zodiacal light levels, and background confusion by stars and galaxies. The python tool utilizes Dmitry Savransky's EXOSIMS (Exoplanet Open-Source Imaging Mission Simulator) design reference mission simulator that is being developed for the WFIRST Preliminary Science program. ExEP is extending and validating the tool for future mission concepts under consideration for the upcoming 2020 decadal review. We present a validation plan and preliminary yield results for a point design.

  4. Engineering study for ISSTRS design concept

    Energy Technology Data Exchange (ETDEWEB)

    Hertzel, J.S.

    1997-01-31

    Los Alamos Technical Associates, Inc., is pleased to transmit the attached Conceptual Design Package for the Initial Single Shell Tank Retrieval System (ISSTRS), 90% Conceptual Design Review. The package includes the following: (1) ISSTRS Trade Studies: (a) Retrieval Facility Cooling Requirements; (b) Equipment Re-usability between Project W-320 and Tanks 241-C-103 and 241-C-1 05; (c) Sluice Line Options; and (d) Options for the Location of Tanks AX-103 and A-1 02 HVAC Equipment; (2) Drawings; (3) Risk Management Plan; (4) 0850 Interface Control Document; (5) Requirements Traceability Report; and (6) Project Design Specification.

  5. Space-Based Gravitational-wave Mission Concept Studies

    Science.gov (United States)

    Livas, Jeffrey C.

    2012-01-01

    The LISA Mission Concept has been under study for over two decades as a spacebased gravitational-wave detector capable of observing astrophysical sources in the 0.0001 to 1 Hz band. The concept has consistently received strong recommendations from various review panels based on the expected science, most recently from the US Astr02010 Decadal Review. Budget constraints have led both the US and European Space agencies to search for lower cost options. We report results from the US effort to explore the tradeoffs between mission cost and science return, and in particular a family of mission concepts referred to as SGO (Space-based Gravitational-wave Observatory).

  6. A Satellite Based Fog Study of the Korean Peninsula

    Science.gov (United States)

    2007-06-01

    total number of fog and fog likely days detected from the two MODIS satellites, Aqua and Tera , respectively. Results from all nine areas of...trends in fog detection based on the satellite differences. 46 0 20 40 60 80 100 120 N um be r o f D ay s 1 2 3 4 5 6 7 8 9 Areas Four Month Tera vs...Aqua Fog Totals Tera Fog Tera Fog Likely Aqua Fog Aqua Fog Likely Figure 29. Comparisons of the four month total number of fog and fog likely days

  7. Study on core concept for commercial LMFBR plant toward self-consistent nuclear energy system concept

    Energy Technology Data Exchange (ETDEWEB)

    Toukura, A. [Institute of Applied Energy, Tokyo (Japan); Yamazaki, M. [Toshiba Corp., Fuchu, Tokyo (Japan). Fuchu Works; Ohashi, M. [Hitachi Ltd., Ibaraki (Japan). Hitachi Works; Ikeda, K. [Mitsubishi Atomic Power Industries, Inc., Tokyo (Japan); Saito, M.; Fujiie, Y. [Tokyo Inst. of Tech. (Japan). Research Lab. for Nuclear Reactors

    1995-12-31

    Fast Breeder Reactor (FBR) is expected to be commercialized in Japan to overcome foreseeable problems such as reactor safety, increasing energy demand, final disposal of high level radioactive waste and fuel resource shortage. We have been studying three FBR core concepts enhancing its potential abilities; ultra-large type, simplified type and friendly to fuel cycle type core. This study is sponsored by Ministry of International Trade and Industry. (author).

  8. Terrestrial kilometric radiation: 1: Spatial structures studies. [from satellite observation (Explorer 2 satellite) of lunar occultation

    Science.gov (United States)

    Alexander, J. K.; Kaiser, M. L.

    1976-01-01

    Observations are presented of lunar occultations of the earth at 250 kHz obtained with the Radio-Astronomy-Explorer-2 satellite which were used to derive two dimensional maps of the location of the sources of terrestrial kilometric radiation (TKR). By examining the two dimensional source distributions as a function of the observer's location (lunar orbit) with respect to the magnetosphere, the average three dimensional location of the emission regions can be estimated. Although TKR events at 250 kHz can often be observed at projected distances corresponding to the 250 kHz electron gyro or plasma level (approximately 2 earth radii), many events are observed much farther from the earth (between 5 and 15 earth radii). Dayside emission apparently in the region of the polar cusp and the magnetosheath and night emission associated with regions of the magnetotail are examined. The nightside emission is suggestive of a mechanism involving plasma sheet electron precipitation in the pre-midnight sector.

  9. Usage Concepts of Augmented Reality Technology in Islamic Study

    Directory of Open Access Journals (Sweden)

    Norabeerah Saforrudin

    2012-06-01

    Full Text Available The augmented reality (AR has been identified to be suitable for use in education. However, studies that particularly identify this concept are still rare. Therefore, this qualitative study was conducted with objectives to determine the perception of teacher educators from the Islamic Study Department, Teacher Training Institute in Central Zone of Malaysia towards AR, and to develop a usage concept that can be implemented when teaching and learning Islamic Study. Explorative case study method involving three teacher educators was used. They were interviewed by using an in-depth semi-structured interview schedule. From the interview, all responses provided by the informants are very positive and admitted that AR technology is suitable to be used in the Islamic Study. The usage concepts discussed in this paper can be used as guidelines to those who are interested in developing or using the AR application based on Islamic Study topics.

  10. Advancements in satellite gravity gradient data for crustal studies

    NARCIS (Netherlands)

    Ebbing, J.; Bauman, J.; Fuchs, M.; Lieb, V.; Haagmans, R.; Meekes, J.A.C.; Abdul Fattah, R.

    2013-01-01

    In recent years, global gravity models, both based only on satellite data and from combination with terrestrial data, are increasingly available and particularly useful to construct regional models before more local interpretations on the exploration scale are carried out. Often it is challenging to

  11. Advancements in satellite gravity gradient data for crustal studies

    NARCIS (Netherlands)

    Ebbing, J.; Bauman, J.; Fuchs, M.; Lieb, V.; Haagmans, R.; Meekes, J.A.C.; Abdul Fattah, R.

    2013-01-01

    In recent years, global gravity models, both based only on satellite data and from combination with terrestrial data, are increasingly available and particularly useful to construct regional models before more local interpretations on the exploration scale are carried out. Often it is challenging to

  12. Suggestions for teacher education from concept mapping studies

    Directory of Open Access Journals (Sweden)

    Priit Reiska

    2015-03-01

    Full Text Available In order to enhance primary and secondary education, teaching and learning methods need to be continuously developed as well as, of course, promote teaching quality dependent on teacher personality, teacher professional development, teacher self-development, etc. Teacher professional development gives the novice teacher access to a wide set of teaching methods and assessment opportunities, especially geared to flexible learning and assessment methods, which can be considered for adoption. One such flexible method is the use of concept mapping. This article describes the results of several studies, where concept mapping method was used, giving many didactical suggestions for using concept mapping for learning and especially for assessment. Additionally, considerations are introduced on using concept maps as a research instrument.

  13. 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.

  14. 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....

  15. Satellite communications principles and applications

    CERN Document Server

    Calcutt, David

    1994-01-01

    Satellites are increasingly used for global communications, as well as for radio and television transmissions. With the growth of mobile communications, and of digital technology, the use of satellite systems is set to expand substantially and already all students of electronics or communications engineering must study the subject.This book steers a middle path between offering a basic understanding of the process of communication by satellite and the methodology used; and the extensive mathematical analysis normally adopted in similar texts. It presents the basic concepts, using as mu

  16. 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.

  17. 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).

  18. 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.

  19. Study, optimization, and design of a laser heat engine. [for satellite applications

    Science.gov (United States)

    Taussig, R. T.; Cassady, P. E.; Zumdieck, J. F.

    1978-01-01

    Laser heat engine concepts, proposed for satellite applications, are analyzed to determine which engine concept best meets the requirements of high efficiency (50 percent or better), continuous operation in space using near-term technology. The analysis of laser heat engines includes the thermodynamic cycles, engine design, laser power sources, collector/concentrator optics, receiving windows, absorbers, working fluids, electricity generation, and heat rejection. Specific engine concepts, optimized according to thermal efficiency, are rated by their technological availability and scaling to higher powers. A near-term experimental demonstration of the laser heat engine concept appears feasible utilizing an Otto cycle powered by CO2 laser radiation coupled into the engine through a diamond window. Higher cycle temperatures, higher efficiencies, and scalability to larger sizes appear to be achievable from a laser heat engine design based on the Brayton cycle and powered by a CO laser.

  20. Management approach recommendations. Earth Observatory Satellite system definition study (EOS)

    Science.gov (United States)

    1974-01-01

    Management analyses and tradeoffs were performed to determine the most cost effective management approach for the Earth Observatory Satellite (EOS) Phase C/D. The basic objectives of the management approach are identified. Some of the subjects considered are as follows: (1) contract startup phase, (2) project management control system, (3) configuration management, (4) quality control and reliability engineering requirements, and (5) the parts procurement program.

  1. Undergraduate Students' Conceptions of Mathematics: An International Study

    Science.gov (United States)

    Petocz, Peter; Reid, Anna; Wood, Leigh N.; Smith, Geoff H.; Mather, Glyn; Harding, Ansie; Engelbrecht, Johann; Houston, Ken; Hillel, Joel; Perrett, Gillian

    2007-01-01

    In this paper, we report on an international study of undergraduate mathematics students; conceptions of mathematics. Almost 1,200 students in five countries completed a short survey including three open-ended questions asking about their views of mathematics and its role in their future studies and planned professions. Responses were analysed…

  2. Basic didactic principles in the study of mathematical concepts

    Directory of Open Access Journals (Sweden)

    Testоv Vladimir

    2016-01-01

    Full Text Available The problem of understanding in the study of basic mathematical concepts in mathematics education has exacerbated during recent years. This is largely due to the fact that the style of thinking of pupils and students thanks to the intensive use of the Web becomes figurative and emotional, less inclined to abstract constructions. Fragments-clip thinking has become more common for most of students. The article deals with the didactic principles to be used in the study of mathematical concepts, which will contribute to achieving understanding.

  3. Wide Field X-Ray Telescope Mission Concept Study Results

    Science.gov (United States)

    Hopkins, R. C.; Thomas, H. D.; Fabisinski, L. L.; Baysinger, M.; Hornsby, L. S.; Maples, C. D.; Purlee, T. E.; Capizzo, P. D.; Percy, T. K.

    2014-01-01

    The Wide Field X-Ray Telescope (WFXT) is an astrophysics mission concept for detecting and studying extra-galactic x-ray sources, including active galactic nuclei and clusters of galaxies, in an effort to further understand cosmic evolution and structure. This Technical Memorandum details the results of a mission concept study completed by the Advanced Concepts Office at NASA Marshall Space Flight Center in 2012. The design team analyzed the mission and instrument requirements, and designed a spacecraft that enables the WFXT mission while using high heritage components. Design work included selecting components and sizing subsystems for power, avionics, guidance, navigation and control, propulsion, structures, command and data handling, communications, and thermal control.

  4. A study of warm rain detection using A-Train satellite data

    National Research Council Canada - National Science Library

    Ruiyue Chen; Zhanqing Li; Robert J. Kuligowski; Ralph Ferraro; Fuzhong Weng

    2011-01-01

    .... This study exploits multi-sensor data from the A-Train satellite constellation to investigate the rain contribution from warm clouds and the potential of using cloud microphysical parameters for warm rain detection...

  5. A Study on the Timing Technology of Digital Satellite TV

    Science.gov (United States)

    Song, K. X.

    2013-03-01

    Based on analyzing and summarizing the modern timing technologies, through intensive analyzing the characteristics of the current digital satellite TV signals, and without changing equipment configuration of the digital satellite TV transmitter and signal system, this thesis puts forward the method of using the digital TV signal to transmit the standard time and frequency, and carries out the relevant researches on the key technologies. Meanwhile, we make experiments on the digital satellite TV timing system, which are based on the proposed timing method. Through analyzing the test data, the timing method is proved practicable and with a high precision. The main research work is as follows: (1) Firstly, we summarize the necessary conditions and key elements required for timing by analyzing the characteristics of modern timing methods, and analyze China’s digital satellite TV signal system; Secondly, we propose the idea that the inherent flag bit of source coding signals of TV is used to trigger event of timing and then complete this task; Thirdly, we propose the principle of transmitting the standard time and frequency through digital satellite TV signal, analyze the error sources which affect the accuracy of timing, and find the ways to reduce the error effect. (2) Synchronization clock signal is recovered from asynchronous serial interface (ASI) data to achieve bit synchronization, so that the transmitter can accurately access to the high-precision standard time code. At the same time, the TV signal transmission delay on the transmission channel is accurately measured in order to supply the necessary information for timing. Based on the analysis of the ASI data transmission characteristics and transmission standards, a method using over-sampling to recover the ASI clock signal and synchronize the digital TV signal source coding is proposed in this paper. This method is proved effective by the implementation on the FPGA (Field Programmable Gate Array). (3) Using

  6. Phonetic compliance: a proof-of-concept study

    Directory of Open Access Journals (Sweden)

    Véronique eDelvaux

    2014-12-01

    Full Text Available In this paper, we introduce the concept of phonetic compliance, which is defined as the intrinsic individual ability to produce speech sounds that are unusual in the native language, and constitutes a part of the ability to acquire L2 phonetics and phonology. We argue that phonetic compliance represents a systematic source of variance that needs to be accounted for if one wants to improve the control over the independent variables manipulated in SLA experimental studies. We then present the results of a two-fold proof-of-concept study aimed at testing the feasibility of assessing phonetic compliance in terms of gradient. In study 1, a pilot data collection paradigm is implemented on an occasional sample of 10 native French speakers engaged in two reproduction tasks involving respectively vowels and aspirated stops, and data are analysed using descriptive statistics. In study 2, complementary data including L1-typical realizations are collected, resulting in the development of a first set of indicators that may be useful to appropriately assess, and further refine the concept of, phonetic compliance. Based on a critical analysis of the contributions and limitations of the proof-of-concept study, general discussion formulates the guidelines for the following stages of development of a reliable and valid test of phonetic compliance.

  7. 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.

  8. TRADITION, PERMANENCY AND SUBVERSION OF CONCEPTS IN LANGUAGE STUDIES

    Directory of Open Access Journals (Sweden)

    Beth Brait

    2013-12-01

    Full Text Available This paper’s aims at showing how, in the XX century, the concept of dialogue starts to be integrated to language studies, gaining consistency and diversity in different trends.  Amid the wealth contribution brought by this concept, we highlight here the works of Emile Benveniste, Lev Jakubinskij, Valentin Voloshinov and Mikhail Bakhtin. Besides the theoretical route, an example of the book cover titled Retrato calado (Silent Portrait, written by Luiz Roberto Salinas Fortes, impels dialogue, in the XXI century, as a way to address, by its verbal-visuality, aesthetic and ideological forces in tension

  9. Analysis on Inclusion of Social Studies Economy Concepts in Coursebooks

    Science.gov (United States)

    Seker, Mustafa; Osmanoglu, Ahmet Emin

    2015-01-01

    Having an efficient and satisfactory economy education may enable an individual to actively participate in decision making process about economy-related issues. This is very important for democratic societies. This research aims to search methods and levels of teaching "economy" concepts prepared for Turkey 2005 Social Studies Program in…

  10. Study on Concept of Centralization and Decentralization Group Decision Making

    Institute of Scientific and Technical Information of China (English)

    ZHANG Qin-sheng; XI You-min; WANG Ying-luo

    2002-01-01

    The paper extracts the concept of Centralization Group Decision Making (CGDM) and Decentralization Group Decision Making (DGDM) from management systems on bases of studies on Informational Centralization Process (ICP) and Informational Decentralization Process (IDP), then the similarities and differences between CGDM and DGDM are presented. Further, the taxonomy of CGDM and DGDM is researched.

  11. Study of Visual Factors in Concept Formation. Final Report.

    Science.gov (United States)

    Arnheim, Rudolf

    The study undertakes to clarify and redefine some of the concepts underlying the relations between visual perception and thinking. A sample bibliography suggests sources for future research. Psychological and psysiological theory is shown historically to have separated the two mental functions in principle. Correspondingly, present-day education,…

  12. Analysis on Inclusion of Social Studies Economy Concepts in Coursebooks

    Science.gov (United States)

    Seker, Mustafa; Osmanoglu, Ahmet Emin

    2015-01-01

    Having an efficient and satisfactory economy education may enable an individual to actively participate in decision making process about economy-related issues. This is very important for democratic societies. This research aims to search methods and levels of teaching "economy" concepts prepared for Turkey 2005 Social Studies Program in…

  13. Identifying Threshold Concepts for Information Literacy: A Delphi Study

    Science.gov (United States)

    Townsend, Lori; Hofer, Amy R.; Hanick, Silvia Lin; Brunetti, Korey

    2016-01-01

    This study used the Delphi method to engage expert practitioners on the topic of threshold concepts--core ideas and processes in a discipline that students need to grasp in order to progress in their learning, but that are often unspoken or unrecognized by expert practitioners--for information literacy. A panel of experts considered two questions:…

  14. On the choice of orbits for an altimetric satellite to study ocean circulation and tides

    Science.gov (United States)

    Parke, Michael E.; Stewart, Robert H.; Farless, David L.; Cartwright, David E.

    1987-01-01

    The choice of an orbit for satellite altimetric studies of the ocean's circulation and tides requires an understanding of the orbital characteristics that influence the accuracy of the satellite's measurements of sea level and the temporal and spatial distribution of the measurements. The orbital characteristics that influence accurate calculations of the satellite's position as a function of time are examined, and the pattern of ground tracks laid down on the ocean's surface as a function of the satellite's altitude and inclination is studied. The results are used to examine the aliases in the measurements of surface geostrophic currents and tides. Finally, these considerations are used to specify possible orbits that may be useful for the upcoming Topex/Poseidon mission.

  15. 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).

  16. 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).

  17. 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

  18. Experimental study of mountain lee—waves by means of satellite photographs and aircraft measurements

    OpenAIRE

    Cruette, Denise

    2011-01-01

    This paper is a summary of a Ph.D. Thesis1 which was a systematic study of the influence of various meteorological factors on the occurrence and characteristics of mountain waves, more specifically of lee-waves of great horizontal extent. The data used are, beside classical meteorological informations, that given by satellite pictures completed by quasi-simultaneous measurements from planes or gliders. The analysis of many satellite pictures received at the french station of Lannion (Brittany...

  19. [Illness Concepts of Patients with Schizophrenia: A Triangulation Study].

    Science.gov (United States)

    Wigand, Moritz E; Reichhardt, Lea; Lang, Fabian U; Krumm, Silvia; Jäger, Markus

    2017-04-03

    Objective Therapists' and patients' concepts of illness often show severe discrepancies. This study explores the illness concepts of patients with schizophrenic disorders (n = 40). Methods Two German scales were used, the "Causal Belief Questionnaire" and the "Illness Concept Scale for Schizophrenic Patients". We compared our data with data published previously. A semi structured interview was performed in a convenience sample (n = 7). Results The domains "trust in medication" and "trust in the treating physician" yielded high scores, yet in comparison with data published 30 years ago, trust in medication is unaltered, while trust in psychiatrists is even slightly lower. Recent psychosocial factors scored high as a possible cause of mental illness. Several patients felt responsible for being mentally ill. No patient in the interview mentioned the neurotransmitter hypothesis of schizophrenia. Conclusion Illness concepts of patients with schizophrenic disorders are a complex phenomenon. Triangulation of quantitative and qualitative methods proves to be a promising approach for future studies. © Georg Thieme Verlag KG Stuttgart · New York.

  20. Two satellite study of substorm expansion near geosynchronous orbit

    Directory of Open Access Journals (Sweden)

    Ø. Holter

    2004-12-01

    Full Text Available During several time intervals in 1979–1980 the satellites GEOS-2 and SCATHA were situated relatively close on the nightside of the Earth at geosynchronous distances. Several substorm events were identified during these periods. The event considered in this paper was recorded on 22 May 1979, when the satellites were separated by less than 30min in local time around 21:00 LT. The observed 45 to 60 s delay of magnetic signatures observed at the two s/c indicates a westward expansion of ~7.7°/min. At the two s/c, the magnetic signatures are, in particular for the azimuthal magnetic field components, quite different. At GEOS-2, being close to the magnetic equator, the dominant feature is a dipolarization with a weak field-aligned current signature corresponding to a symmetric current which cancels at the equator. On SCATHA, however, being close to the current sheet boundary, the azimuthal magnetic field indicates a strong field-aligned Birkeland current structure. On both s/c the first indication of an approaching substorm was an increase in the high energy ion flux followed by a reduction in the flux intensity of energetic electrons and a further tailward stretching of the magnetic field, starting ~2min before the onset of the magnetic field dipolarization. The tailward stretching, the observed variations of the magnetic field components, and the subsequent dipolarization are interpreted in terms of an azimuthally tilted field-aligned current system passing the s/c on the tailward side from east to west. The westward expansion and dipolarization observed at the two s/c are consistent with the propagation of a Rayleigh-Taylor type instability. The increased radial ion flux corresponds to the ExB-drift due to the substorm associated electric field.

    Key words. Magnetospheric physics (storms and substorms; plasma waves and instabilities; current systems

  1. The concept of care complexity: a qualitative study

    Directory of Open Access Journals (Sweden)

    Milena Guarinoni

    2015-12-01

    Full Text Available Background: Hospital organisations based on the level of care intensity have clearly revealed a concept, that of care complexity, which has been widely used for decades in the healthcare field. Despite its wide use, this concept is still poorly defined and it is often confused with and replaced by similar concepts such as care intensity or workload. This study aims to describe the meaning of care complexity as perceived by nurses in their day-to-day experience of hospital clinical care, rehabilitation, home care, and organisation. Design and methods: Fifteen interviews were conducted with nurses belonging to clinical-care areas and to heterogeneous organisational areas. The interview was of an unstructured type. The participants were selected using a propositional methodology. Colaizzi’s descriptive phenomenological method was chosen for the analysis of the interviews. Results: The nurses who were interviewed predominantly perceive the definition of care complexity as coinciding with that of workload. Nevertheless, the managerial perspective does not appear to be exclusive, as from the in-depth interviews three fundamental themes emerge that are associated with the concept of care complexity: the patient, the nurse and the organisation. Conclusions: The study highlights that care complexity consists of both quantitative and qualitative aspects that do not refer only to the organisational dimension. The use of the terminology employed today should be reconsidered: it appears to be inappropriate to talk of measurement of care complexity, as this concept also consists of qualitative – thus not entirely quantifiable – aspects referring to the person being cared for. In this sense, reference should instead be made to the evaluation of care complexity, which would also constitute a better and more complete basis for defining the nursing skills required in professional nursing practice.

  2. Sampling error study for rainfall estimate by satellite using a stochastic model

    Science.gov (United States)

    Shin, Kyung-Sup; North, Gerald R.

    1988-01-01

    In a parameter study of satellite orbits, sampling errors of area-time averaged rain rate due to temporal sampling by satellites were estimated. The sampling characteristics were studied by accounting for the varying visiting intervals and varying fractions of averaging area on each visit as a function of the latitude of the grid box for a range of satellite orbital parameters. The sampling errors were estimated by a simple model based on the first-order Markov process of the time series of area averaged rain rates. For a satellite of nominal Tropical Rainfall Measuring Mission (Thiele, 1987) carrying an ideal scanning microwave radiometer for precipitation measurements, it is found that sampling error would be about 8 to 12 pct of estimated monthly mean rates over a grid box of 5 X 5 degrees. It is suggested that an observation system based on a low inclination satellite combined with a sunsynchronous satellite simultaneously might be the best candidate for making precipitation measurements from space.

  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. 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.

  6. Concepts of Culture in Middle Eastern and Islamic Studies

    Directory of Open Access Journals (Sweden)

    Pierre Hecker

    2017-01-01

    Full Text Available Introducing the seventh issue of META, this editorial discusses prevalent concepts of culture in Islamic and Middle Eastern Studies. Different conceptualizations of culture that explicitly or implicitly contain qualitative differentiations between cultures are revisited and discussed. Bearing considerable weight in the respective disciplines, the Islam-andthe-West paradigm, the delineation of diverging cultures along ethnic lines, the equation of culture with art or religion, and the culture-as-civilization paradigm are being scrutinized. Serving as an example for the confusion and lack of clarity regarding the concept of "culture", the book The Culture of Ambiguity by the German scholar of Islamic Studies Thomas Bauer is analyzed regarding its use of the term.

  7. Multi-satellite rainfall sampling error estimates – a comparative study

    Directory of Open Access Journals (Sweden)

    A. Loew

    2012-10-01

    Full Text Available This study focus is set on quantifying sampling related uncertainty in the satellite rainfall estimates. We conduct observing system simulation experiment to estimate sampling error for various constellations of Low-Earth orbiting and geostationary satellites. There are two types of microwave instruments currently available: cross track sounders and conical scanners. We evaluate the differences in sampling uncertainty for various satellite constellations that carry instruments of the common type as well as in combination with geostationary observations. A precise orbital model is used to simulate realistic satellite overpasses with orbital shifts taken into account. With this model we resampled rain gauge timeseries to simulate satellites rainfall estimates free of retrieval and calibration errors. We concentrate on two regions, Germany and Benin, areas with different precipitation regimes. Our results show that sampling uncertainty for all satellite constellations does not differ greatly depending on the area despite the differences in local precipitation patterns. Addition of 3 hourly geostationary observations provides equal performance improvement in Germany and Benin, reducing rainfall undersampling by 20–25% of the total rainfall amount. Authors do not find a significant difference in rainfall sampling between conical imager and cross-track sounders.

  8. CMBPol Mission Concept Study: A Mission to Map our Origins

    CERN Document Server

    Baumann, Daniel; Dodelson, Scott; Dunkley, Joanna; Fraisse, Aurélien A; Jackson, Mark G; Kogut, Al; Krauss, Lawrence M; Smith, Kendrick M; Zaldarriaga, Matias

    2008-01-01

    Quantum mechanical metric fluctuations during an early inflationary phase of the universe leave a characteristic imprint in the polarization of the cosmic microwave background (CMB). The amplitude of this signal depends on the energy scale at which inflation occurred. Detailed observations by a dedicated satellite mission (CMBPol) therefore provide information about energy scales as high as $10^{15}$ GeV, twelve orders of magnitude greater than the highest energies accessible to particle accelerators, and probe the earliest moments in the history of the universe. This summary provides an overview of a set of studies exploring the scientific payoff of CMBPol in diverse areas of modern cosmology, such as the physics of inflation, gravitational lensing and cosmic reionization, as well as foreground science and removal .

  9. CMBPol Mission Concept Study: Foreground Science Knowledge and Prospects

    CERN Document Server

    Fraisse, A A; Dobler, G; Dotson, J L; Draine, B T; Frisch, P C; Haverkorn, M; Hirata, C M; Jansson, R; Lazarian, A; Magalhães, A M; Waelkens, A; Wolleben, M

    2008-01-01

    We report on our knowledge of Galactic foregrounds, as well as on how a CMB satellite mission aiming at detecting a primordial B-mode signal (CMBPol) will contribute to improving it. We review the observational and analysis techniques used to constrain the structure of the Galactic magnetic field, whose presence is responsible for the polarization of Galactic emissions. Although our current understanding of the magnetized interstellar medium is somewhat limited, dramatic improvements in our knowledge of its properties are expected by the time CMBPol flies. Thanks to high resolution and high sensitivity instruments observing the whole sky at frequencies between 30 GHz and 850 GHz, CMBPol will not only improve this picture by observing the synchrotron emission from our galaxy, but also help constrain dust models. Polarized emission from interstellar dust indeed dominates over any other signal in CMBPol's highest frequency channels. Observations at these wavelengths, combined with ground-based studies of starlig...

  10. External field characterization using CHAMP satellite data for induction studies

    Indian Academy of Sciences (India)

    Praveen Kunagu; E Chandrasekhar

    2013-06-01

    Knowledge of external inducing source field morphology is essential for precise estimation of electromagnetic (EM) induction response. A better characterization of the external source field of magnetospheric origin can be achieved by decomposing it into outer and inner magnetospheric contributions, which are best represented in Geocentric Solar Magnetospheric (GSM) and Solar Magnetic (SM) reference frames, respectively. Thus we propose a spherical harmonic (SH) model to estimate the outer magnetospheric contribution, following the iterative reweighted least squares approach, using the vector magnetic data of the CHAMP satellite. The data covers almost a complete solar cycle from July 2001 to September 2010, spanning 54,474 orbits. The SH model, developed using orbit-averaged vector magnetic data, reveals the existence of a stable outer magnetospheric contribution of about 7.39 nT. This stable field was removed from the CHAMP data after transforming to SM frame. The residual field in the SM frame acts as a primary source for induction in the Earth. The analysis of this time-series using wavelet transformation showed a dominant 27-day periodicity of the geomagnetic field. Therefore, we calculated the inductive EM -response function in a least squares sense considering the 27-day period variation as the inducing signal. From the estimated -response, we have determined that the global depth to the perfect substitute conductor is about 1132 km and its conductivity is around 1.05 S/m.

  11. Studies of outer planet satellites, Mercury and Uranus

    Science.gov (United States)

    Mckinnon, William B.; Schenk, Paul M.

    1987-01-01

    Arguments were made, based on geometry, for both an impact and an internal origin for the ancient, partially preserved furrow system of Ganymede. It was concluded that furrows were not concentric, but could be impact related if multiringed structures on icy satellites are initially noncircular. The geometry of the Valhalla ring structure on Callisto was examined in order to assess the circularity of an unmodified ring system. The Ganymede furrow system was remapped to make use of improvements in coordinate control. The least-squares center of curvature for all furrows in the Marius and Galileao Regio is -20.7, and 179.2 degrees. Furrows in Marius and Galileo Regio are reasonably concentric, and are much more circular than previously estimated. The perceived present nonalignment of the assumed originally concentric furrows were used to argue for large-scale lateral motion of dark terrain blocks in Ganymede's crust, presumably in association with bright terrain formation., The overall alignment of furrows as well as the inherent scatter in centers of curvature from subregions of Galileo and Marius do not support this hypothesis.

  12. Multibeam Satellite Frequency/Time Duality Study and Capacity Optimization

    CERN Document Server

    Lei, Jiang

    2011-01-01

    In this paper, we investigate two new candidate transmission schemes, Non-Orthogonal Frequency Reuse (NOFR) and Beam-Hoping (BH). They operate in different domains (frequency and time/space, respectively), and we want to know which domain shows overall best performance. We propose a novel formulation of the Signal-to-Interference plus Noise Ratio (SINR) which allows us to prove the frequency/time duality of these schemes. Further, we propose two novel capacity optimization approaches assuming per-beam SINR constraints in order to use the satellite resources (e.g. power and bandwidth) more efficiently. Moreover, we develop a general methodology to include technological constraints due to realistic implementations, and obtain the main factors that prevent the two technologies dual of each other in practice, and formulate the technological gap between them. The Shannon capacity (upper bound) and current state-of-the-art coding and modulations are analyzed in order to quantify the gap and to evaluate the performa...

  13. The Development of Preschoolers' Living Kinds Concept: A Longitudinal Study.

    Science.gov (United States)

    Margett-Jordan, Tessa; Falcon, Rachael G; Witherington, David C

    2016-12-19

    Given limitations in the integrative scope of past research, basic questions about the organization and development of preschoolers' living kinds concept remain open to debate. This study was designed to address past limitations through use of a longitudinal design, extensive stimulus set, and alternate indices of understanding. Thirty-five English-speaking 3-year-olds from middle-class families in Albuquerque, NM participated in four testing sessions over 1 year. Indices of understanding included statements that preschoolers generated about various living and nonliving objects, biological properties they attributed to the objects, and their characterization of objects as "alive" or not. Results reveal a multifaceted picture of developmental change in preschoolers' living kinds concept involving both the construction and elaboration of a core biological understanding.

  14. 3D CAD for concept design - a case study

    Directory of Open Access Journals (Sweden)

    S.K. Mandal

    2013-07-01

    Full Text Available Generally for any new design initially a concept layout in 2D CAD is generated. But sometimes if the geometry of product becomes complicated, then 3D CAD model is preferred. Because 3D CAD model can give us a complete all side view at a time like a real product, but in a virtual world. The present case study will show the utilization of 3D CAD at the concept design stage of a complicated shaped product for a new system. This will also give an idea about cost and time comparison. Thus this paper will describe about the importance of 3D CAD tools for product development. 

  15. Multi-life cycles utilization of retired satellites

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Retired geosynchronous (GEO) communication satellites affect the GEO orbit environment in outer space. According to the new concept of modern design, the authors propose creatively a method of reusing retired GEO communication satellites, through adjusting retired GEO satellites to slightly inclined orbit geosynchronous (SIGSO) satellites. After these retired satellites are applied to the navigation and communication system, integrity of navigation system and positioning accuracy of the system is improved. Meanwhile, some transponders on these retired satellites can be used to establish a new satellite communication service, and initiate the study and utilization of the multi-life cycle for retired satellites. Experimental results show that this project has significant social value and can make remarkable economic benefit.

  16. Multi-life cycles utilization of retired satellites

    Institute of Scientific and Technical Information of China (English)

    SHI HuLi; AI GuoXiang; HAN YanBen; MA LiHua; CHEN JiBin; GENG JianPing

    2009-01-01

    Retired geosynchronous (GEO) communication satellites affect the GEO orbit environment in outer apace.According to the new concept of modern design,the authors propose creatively a method of reusing retired GEO communication satellites,through adjusting retired GEO satellites to slightly inclined orbit geosynchronous (SIGSO) satellites.After these retired satellites are applied to the navigation and communication system,integrity of navigation system and positioning accuracy of the system is improved.Meanwhile,some transponders on these retired satellites can be used to establish a new satellite communication service,and initiate the study and utilization of the multi-life cycle for retired satellites.Experimental results show that this project has significant social value and can make remarkable economic benefit.

  17. SLS launched missions concept studies for LUVOIR mission

    Science.gov (United States)

    Stahl, H. Philip; Hopkins, Randall C.

    2015-09-01

    NASA's "Enduring Quests Daring Visions" report calls for an 8- to 16-m Large UV-Optical-IR (LUVOIR) Surveyor mission to enable ultra-high-contrast spectroscopy and coronagraphy. AURA's "From Cosmic Birth to Living Earth" report calls for a 12-m class High-Definition Space Telescope to pursue transformational scientific discoveries. The multi-center ATLAST Team is working to meet these needs. The MSFC Team is examining potential concepts that leverage the advantages of the SLS (Space Launch System). A key challenge is how to affordably get a large telescope into space. The JWST design was severely constrained by the mass and volume capacities of its launch vehicle. This problem is solved by using an SLS Block II-B rocket with its 10-m diameter x 30-m tall fairing and estimated 45 mt payload to SE-L2. Previously, two development study cycles produced a detailed concept called ATLAST-8. Using ATLAST-8 as a point of departure, this paper reports on a new ATLAST-12 concept. ATLAST-12 is a 12-m class segmented aperture LUVOIR with an 8-m class center segment. Thus, ATLAST-8 is now a de-scope option.

  18. The Oxford Conception Study design and recruitment experience.

    Science.gov (United States)

    Pyper, Cecilia; Bromhall, Lise; Dummett, Sarah; Altman, Douglas G; Brownbill, Pat; Murphy, Michael

    2006-11-01

    The Oxford Conception Study is a randomised controlled trial that aims to determine whether or not information about potential fertility from a device that monitors urinary hormones will increase the conception rate in women wishing to conceive. Three modified versions of a fertility monitor have been developed for the study. The monitor measures the levels of urinary oestrone-3-glucuronide (E3G) and luteinising hormone (LH), and the display indicates high or low fertility. The monitor requests all women to test their urine from day 6 to day 25 of the menstrual cycle inclusive. One-third of women are randomised to receive information from the fertility monitor about the early fertile time (from the first rise in E3G until the LH surge is detected), one-third receive information about the late fertile time (the onset of the LH surge and the following 2 days), and a third do not receive any information (control group). All the women are followed up for 6 months or until they are pregnant. A total of 1453 women have been recruited into the study, reaching the study recruitment goal for 80% power to detect a 10% difference in three-cycle pregnancy rate between the Late Fertile Time group (50%) and the Control group (40%), allowing for a 15% non-pregnancy drop-out rate. Follow-up of the women is currently ongoing. The primary analysis will compare the cumulative three-cycle pregnancy rate between each of the study arms. Time-specific conception probabilities will be estimated from coitus information recorded in 12-h intervals. The data from this study will also allow many additional questions to be addressed, including changes in intercourse patterns with feedback about the fertile days and other questions in relation to menstrual cycle function, sexual intercourse, stress, exposures to tobacco products, alcohol, caffeine and medications, fertility and pregnancy outcomes. In addition to presenting the study design, we review the recruitment experience for the Oxford

  19. The Full-sky Astrometric Mapping Explorer Concept Study

    Science.gov (United States)

    Horner, S. D.; Germain, M. E.; Greene, T. P.; Harris, F. H.; Johnson, M. S.; Johnston, K. J.; Monet, D. G.; Murison, M. A.; Phillips, J. D.; Reasenberg, R. D.; Seidelmann, P. K.; Talabac, S. J.; Urban, S. E.; van Buren, D.; Vassar, R. H.

    1999-05-01

    NASA has selected the Full-sky Astrometric Mapping Explorer (FAME) to be one of five MIDEX missions to be funded for a concept study. This concept study will be submitted to NASA on 18 June, with final selection, scheduled for September, of two of these missions for flight in 2003 or 2004. FAME is designed to perform an all-sky, astrometric survey with unprecedented accuracy. It will create a rigid astrometric catalog of 40,000,000 stars with visual band magnitudes 5 DSS colors. During the concept study, the team has worked to optimize the scientific return from FAME while minimizing cost and risk. The optical design was modified for improved accuracy of individual observations and improved mechanical design. The optical, mechanical, and thermal design of the instrument have been improved. Tests using CCDs in TDI mode are being conducted to confirm the accuracy obtainable from individual observations as well as determine the optimal clocking scheme for astrometric devices operated in TDI mode. The use of solar radiation pressure for spacecraft precession has undergone further feasibility study, as have the mechanisms for deploying the solar shield. Numerous other trade studies have been conducted, including orbit/communications, on board processing, and the use of neutral density filters for astrometry of bright stars versus other options. A detailed error budget has been formulated and the mission requirements have been defined. We look forward to selection for launch and a successful FAME mission that will redefine the extragalactic distance scale and provide a large, rich database of information on stellar properties that will enable numerous science investigations into stellar structure and evolution, the dynamics of the Milky Way, and stellar companions including brown dwarfs and giant planets. FAME is a joint development effort of the US Naval Observatory, the Smithsonian Astrophysical Observatory, the Infrared Processing and Analysis Center, Lockheed Martin

  20. A circumzenithal arc to study optics concepts with geometrical optics

    Science.gov (United States)

    Isik, Hakan

    2017-05-01

    This paper describes the formation of a circumzenithal arc for the purpose of teaching light and optics. A circumzenithal arc, an optic formation rarely witnessed by people, is formed in this study using a water-filled cylindrical glass illuminated by sunlight. Sunlight refracted at the top and side surfaces of the glass of water is dispersed into its constituent colours. First, multi-colour arcs are observed on paper at the bottom of the glass. Then, a single arc for each colour is observed on the floor when the rays are allowed to propagate to the furthest points from the glass. The change in observations is explained by formulating an equation for the geometry of the situation. The formula relates each point on the first refracting surface for an incoming light ray to a point further from the second refracting surface. Then, a parallel graph is drawn to visualize the superposition of colours to the formation of a single arc. The geometrical optics studies in this paper exemplify the concept of Snell’s law, total internal reflection and dispersion. The duration of the observation on a circumzenithal arc is limited by the altitude of the Sun in the sky. This study depends on the use of astronomy software to track solar altitude. Pedagogical aspects of the study are discussed for inquiry-based teaching and learning of light and optics concepts.

  1. Quest for learning: A study of teachers' perceptions of the Satellite Education and Environmental Research Program

    Science.gov (United States)

    Ahern, Kathryn A.

    The purpose of this study was to examine the perceptions of teachers who participated in the Satellite Education and Environmental Research (SEER) Program Water Project, a curriculum design course developed at the University of Nebraska-Lincoln. The distance education course was a complex intervention which used the Nebraska Mathematics and Science Initiative's Model Program criteria for inquiry-based curriculum. Teachers formed communities of inquiry, experienced scientific inquiry processes, integrated different disciplines to create new thematic science curricula, and were encouraged to employ innovative pedagogical practices. National Science Education Standards and Nebraska Mathematics and Science Frameworks were consulted to develop important science process skills and concepts. Multicultural science education was addressed through investigation of local water issues. Teachers were encouraged to form community partnerships, supported with testing materials for conducting scientific research, and expected to use computer technology. Grounded theory was used to examine interviews of 26 participants for their perceptions of the effects of the intervention on their teaching strategies. The self-reports were triangulated through the external evaluation report, classroom artifacts, and a limited number of observations of classroom and field activities. Open coding was used to categorize the interview responses and to propose relationships among them. The central phenomenon that emerged from the axial and select coding was the changed focus: teaching science more thematically. Three theoretical propositions were posed to guide further inquiry: (1) teachers need opportunities and resources to experience science as an authentic, tenable, and realistic process if they are to develop curriculum and focus classroom activities on scientific inquiry; (2) autonomous learning communities must be fostered at downlink sites if distance learning experiences are to affect

  2. SATELLITE GRAVITY SURVEYING TECHNOLOGY AND RESEARCH OF EARTH'S GRAVITY FIELD

    Institute of Scientific and Technical Information of China (English)

    Ning Jinsheng

    2003-01-01

    This is a summarized paper. Two topics are discussed: Firstly, the concept, development and application of four kinds of satellite gravity surveying technology are introduced; Secondly, some problems of theory and method, which must be considered in the study of the Earth's gravity field based on satellite gravity data, are expounded.

  3. A study on quality and availability of COCTS images of HY- 1 satellite by simulation

    Institute of Scientific and Technical Information of China (English)

    李淑菁; 毛天明; 潘德炉

    2002-01-01

    Hy-1 is a first China's ocean color satellite which will be launched as a piggyback satellite on FY- 1 satellite using Long March rocket. On the satellite there are two sensors: one is the China's ocean color and temperature scanner (COCTS), the other is CCD coastal zone imager (CZI).The COCTS is considered to be a main sensor to play a key role. In order to understand the characteristics of future ocean color images observed, a simulation and evaluation study on the quality and availability of the COCTS image has been done. First, the simulation models are introduced briefly, and typical simulated cases of radiance images at visible bands are introduced, in which the radiance distribution is based on geographic location, the satellite orbital parameters and sensor properties, the simulated method to evaluate the image quality and availability is developed by using the characteristics of image called the complex signal noise ratio ( CSNR ). Meanwhile, a series of the CSNR images are generated from the simulated radiance components for different cases, which can be used to evaluate the quality and availability of the COCTS images before the HY - 1 is placed in orbit. Finally, the quality and availability of the COCTS images are quantitatively analyzed with the simulated CSNR data. The results will be beneficial to all scientists who are in charge of the COCTS mission and to those who plan to use the data from the COCTS.

  4. Experimental Study on the Precise Orbit Determination of the BeiDou Navigation Satellite System

    Directory of Open Access Journals (Sweden)

    Jens Wickert

    2013-03-01

    Full Text Available The regional service of the Chinese BeiDou satellite navigation system is now in operation with a constellation including five Geostationary Earth Orbit satellites (GEO, five Inclined Geosynchronous Orbit (IGSO satellites and four Medium Earth Orbit (MEO satellites. Besides the standard positioning service with positioning accuracy of about 10 m, both precise relative positioning and precise point positioning are already demonstrated. As is well known, precise orbit and clock determination is essential in enhancing precise positioning services. To improve the satellite orbits of the BeiDou regional system, we concentrate on the impact of the tracking geometry and the involvement of MEOs, and on the effect of integer ambiguity resolution as well. About seven weeks of data collected at the BeiDou Experimental Test Service (BETS network is employed in this experimental study. Several tracking scenarios are defined, various processing schemata are designed and carried out; and then, the estimates are compared and analyzed in detail. The results show that GEO orbits, especially the along-track component, can be significantly improved by extending the tracking network in China along longitude direction, whereas IGSOs gain more improvement if the tracking network extends in latitude. The involvement of MEOs and ambiguity-fixing also make the orbits better.

  5. Second-generation mobile satellite system. A conceptual design and trade-off study

    Science.gov (United States)

    Sue, M. K.; Park, Y. H.

    1985-01-01

    In recent years, interest has grown in the mobile satellite (MSAT) system, a satellite-based communications system capable of providing integrated voice and data services to a large number of users. To explore the potential of a commercial mobile satellite system (MSS) beyond the horizon of the first generation, using technologies of the 1990's and to assist MSAT-X in directing its efforts, a conceptual design has been performed for a second-generation system to be launched around the mid-1990's. The design goal is to maximize the number of satellite channels and/or minimize the overall life-cycle cost, subject to the constraint of utilizing a commercial satellite bus with minimum modifications. To provide an optimal design, a series of trade-offs are performed, including antenna sizing, feed configurations, and interference analysis. Interference is a serious problem for MSAT and often an overlapping feed design is required to reduce interbeam interference. The trade-off studies will show that a simple non-overlapping feed is sufficient for the second-generation system, thus avoiding the need for the complicated beam-forming network that is associated with the overlapping feed designs. In addition, a system that operates at L-band, an alternative frequency band that is being considered by some for possible MSAT applications, is also presented.

  6. Digital Radio Broadcasting using the mixed satellite/terrestrial approach: An application study

    Science.gov (United States)

    Paiement, Richard V.; Voyer, Rene; Prendergast, Doug

    1995-01-01

    Digital radio broadcasting (DRB) is a new service that offers CD quality stereo programs to fixed, portable and mobile receivers. Terrestrial DRB in Canada is considered as a replacement technology for existing AM and FM services, and it is expected to start up in 1996. Canada currently favors Eureka 147 technology operating in the L-band, in the 1452-1492 MHz frequency band allocated during WARC'92 for DRB. Terrestrial DRB delivery is appropriate for small to medium sized service areas, such as cities and their associated suburbs. For larger areas such as provinces, as well as for sparsely populated areas such as the regions in northern Canada, satellite delivery is more appropriate. The mixed approach is based on both satellite and terrestrial broadcasting services using a common frequency band. Spectrum efficiency is achieved through close coordination of both service types, to achieve proper frequency sharing and spectrum re-use. As well, use of a common transmission format by both types of services allows for a common receiver. This mixed satellite/terrestrial approach to DRB is being seriously considered in Canada and in other countries. This paper studies the feasibility of such a mixed satellite/terrestrial DRB system. It looks at possible coverage scenarios for Canada, and at the satellite and receiver technology requirements.

  7. Study on Spacelab software development and integration concepts

    Science.gov (United States)

    1974-01-01

    A study was conducted to define the complexity and magnitude of the Spacelab software challenge. The study was based on current Spacelab program concepts, anticipated flight schedules, and ground operation plans. The study was primarily directed toward identifying and solving problems related to the experiment flight application and tests and checkout software executing in the Spacelab onboard command and data management subsystem (CDMS) computers and electrical ground support equipment (EGSE). The study provides a conceptual base from which it is possible to proceed into the development phase of the Software Test and Integration Laboratory (STIL) and establishes guidelines for the definition of standards which will ensure that the total Spacelab software is understood prior to entering development.

  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. 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

  10. Study on application potentiality of the first China's ocean satellite HY- 1A

    Institute of Scientific and Technical Information of China (English)

    Pan Delu; He Xianqiang; Li Shujing; Gong Fang

    2003-01-01

    China has launched her first ocean color satellite HY- 1A on May 15, 2002 since American ocean color satellite SeaSTAR was on the orbit in 1997. First, the properties and characteristics of HY - 1A are briefly introduced; second, the quality and availability are evaluated by means of the complex signal noise ratio (CSNR) which is simulated theoretically; third, the received HY- 1A data are compared with SeaSTAR data to understand the accuracy of radiance measurement by the HY- 1A; finally, the remote sensing products of ocean color and temperature are mapped to study the application potentiality of HY- 1A. The results show that the HY- 1A has its latent capability for the application of marine environment detection, the management and protection of marine resources, and the national rights and interests. Meanwhile some suggestions are proposed to modify the next ocean satellite.

  11. Validation of PV performance models using satellite-based irradiance measurements : a case study.

    Energy Technology Data Exchange (ETDEWEB)

    Stein, Joshua S.; Parkins, Andrew (Clean Power Research); Perez, Richard (University at Albany)

    2010-05-01

    Photovoltaic (PV) system performance models are relied upon to provide accurate predictions of energy production for proposed and existing PV systems under a wide variety of environmental conditions. Ground based meteorological measurements are only available from a relatively small number of locations. In contrast, satellite-based radiation and weather data (e.g., SUNY database) are becoming increasingly available for most locations in North America, Europe, and Asia on a 10 x 10 km grid or better. This paper presents a study of how PV performance model results are affected when satellite-based weather data is used in place of ground-based measurements.

  12. The FODA-TDMA satellite access scheme - Presentation, study of the system, and results

    Science.gov (United States)

    Celandroni, Nedo; Ferro, Erina

    1991-12-01

    A description is given of FODA-TDMA, a satellite access scheme designed for mixed traffic. The study of the system is presented and the choice of some parameters is justified. A simplified analytic solution is found, describing the steady-state behavior of the system. Some results of the simulation tests for an already existing hardware environment are also presented for the channel speeds of 2 and 8 Mb/s, considering both the stationary and the transient cases. The results of the experimentation at 2 Mb/s on the satellite Eutelsat-F2 are also presented and compared with the results of the simulation.

  13. Updating Object for GIS Database Information Using High Resolution Satellite Images: a Case Study Zonguldak

    Science.gov (United States)

    Alkan, M.; Arca, D.; Bayik, Ç.; Marangoz, A. M.

    2011-09-01

    Nowadays Geographic Information Systems (GIS) uses Remote Sensing (RS) data for a lot of applications. One of the application areas is the updating of the GIS database using high resolution imagery. In this context high resolution satellite imagery data is very important for many applications areas today's and future. And also, high resolution satellite imagery data will be used in many applications for different purposes. Information systems needs to high resolution imagery data for updating. Updating is very important component for the any of the GIS systems. One of this area will be updated and kept alive GIS database information. High resolution satellite imagery is used with different data base which serve map information via internet and different aims of information systems applications in future topographic and cartographic information systems will very important in our country in this sense use of the satellite images will be unavoidable. In this study explain to how is acquired to satellite images and how is use this images in information systems for object and roads. Firstly, pan-sharpened two of the IKONOS's images have been produced by fusion of high resolution PAN and MS images using PCI Geomatica v9.1 software package. Automatic object extraction has been made using eCognition v4.0.6. On the other hand, these objects have been manually digitized from high resolution images using ArcGIS v9.3. software package. Application section of in this study, satellite images data will be compared each other and GIS objects and road database. It is also determined which data is useful in Geographic Information Systems. Finally, this article explains that integration of remote sensing technology and GIS applications.

  14. Parameter Impact on Sharing Studies Between UAS CNPC Satellite Transmitters and Terrestrial Systems

    Science.gov (United States)

    Kerczewski, Robert J.; Wilson, Jeffrey D.; Bishop, William D.

    2015-01-01

    In order to provide a control and non-payload communication (CNPC) link for civil-use unmanned aircraft systems (UAS) when operating in beyond-line-of-sight (BLOS) conditions, satellite communication links are generally required. The International Civil Aviation Organization (ICAO) has determined that the CNPC link must operate over protected aviation safety spectrum allocations. Although a suitable allocation exists in the 5030-5091 MHz band, no satellites provide operations in this band and none are currently planned. In order to avoid a very lengthy delay in the deployment of UAS in BLOS conditions, it has been proposed to use existing satellites operating in the Fixed Satellite Service (FSS), of which many operate in several spectrum bands. Regulatory actions by the International Telecommunications Union (ITU) are needed to enable such a use on an international basis, and indeed Agenda Item (AI) 1.5 for the 2015 World Radiocommunication Conference (WRC) was established to decide on the enactment of possible regulatory provisions. As part of the preparation for AI 1.5, studies on the sharing FSS bands between existing services and CNPC for UAS are being contributed by NASA and others. These studies evaluate the potential impact of satellite CNPC transmitters operating from UAS on other in-band services, and on the potential impact of other in-band services on satellite CNPC receivers operating on UAS platforms. Such studies are made more complex by the inclusion of what are essentially moving FSS earth stations, compared to typical sharing studies between fixed elements. Hence, the process of determining the appropriate technical parameters for the studies meets with difficulty. In order to enable a sharing study to be completed in a less-than-infinite amount of time, the number of parameters exercised must be greatly limited. Therefore, understanding the impact of various parameter choices is accomplished through selectivity analyses. In the case of sharing

  15. Concept study of a vegetation lidar on International Space Station

    Science.gov (United States)

    Kimura, T.; Imai, T.; Sakaizawa, D.; Kobayashi, T.; Murooka, J.

    2015-10-01

    IPCC Fifth Assessment Report says that there are still large uncertainties of carbon flux estimations in the interaction between ground and atmosphere. That is because of the uncertainties of "change of land use", in other words, "change of biomass" such as deforestation. Biomass estimation needs not only area of the forest but also its height information with topological features. In that sense, active sensors are highly expected for precise height measurement. Laser Altimeter or simply LIDAR is able to measure the height of dense forest, where SAR has salutation. ICESat / GLAS is firstly used to measure biomass as satellite LIDAR. However it was reported that there is uncertainty where terrain relief exists. To calibrate terrain relief using multi footprints, a Vegetation LIDAR named MOLI (Multi Observation LIDAR and Imager) was studied by JAXA. The unique points of MOLI are the dual beams with enough small and close footprints to determine terrain relief. Full wave analysis technique is also under development to distinguish canopy heights, crown depth and other forest features. Co-aligned imager will be used for determination of positions where LIDAR measured and observation of phonology. MOLI system design is about to finalize. Regarding Laser Transmitter, Bread Board Model with pressure vessel is being tested under vacuum condition. Target launch year of MOLI is around 2019.

  16. TOLNet - A Tropospheric Ozone Lidar Profiling Network for Satellite Continuity and Process Studies

    Science.gov (United States)

    Newchurch, Michael J.; Kuang, Shi; Wang, Lihua; LeBlanc, Thierry; Alvarez II, Raul J.; Langford, Andrew O.; Senff, Christoph J.; Brown, Steve; Johnson, Bryan; Burris, John F.; hide

    2015-01-01

    NASA initiated an interagency ozone lidar observation network under the name TOLNet to promote cooperative multiple-station ozone-lidar observations to provide highly time-resolved (few minutes) tropospheric-ozone vertical profiles useful for air-quality studies, model evaluation, and satellite validation.

  17. Celebrate with SATELLITES: An International Polar Year Partnership to Study Earth's Materials

    Science.gov (United States)

    Hedley, Mikell Lynne; Czajkowski, Kevin; Struble, Janet; Benko, Terri; Shellito, Brad; Sheridan, Scott; Stasiuk, Mandy Munroe

    2009-01-01

    The SATELLITES program uses geospatial technologies to study surface temperatures of Earth's materials, such as sand, soil, grass, and water. Data are collected using Global Learning and Observations to Benefit the Environment (GLOBE) protocols, which are then used in research projects that are a part of the International Polar Year (IPY).…

  18. Students' Acquisition of a Threshold Concept in Childhood and Youth Studies

    Science.gov (United States)

    Ashworth, Helen

    2016-01-01

    This paper follows undergraduate students' engagement with the concept of childhood presented to them during a year-long childhood and youth studies module. Through the application of "threshold concepts" as concepts which transform students' understandings of a subject, the challenges of learning new ideas or concepts of childhood are…

  19. Electrolysis Performance Improvement Concept Study (EPICS) Flight Experiment-Reflight

    Science.gov (United States)

    Schubert, F. H.

    1997-01-01

    The Electrolysis Performance Improvement Concept Study (EPICS) is a flight experiment to demonstrate and validate in a microgravity environment the Static Feed Electrolyzer (SFE) concept which was selected for the use aboard the International Space Station (ISS) for oxygen (O2) generation. It also is to investigate the impact of microgravity on electrochemical cell performance. Electrochemical cells are important to the space program because they provide an efficient means of generating O2 and hydrogen (H2) in space. Oxygen and H2 are essential not only for the survival of humans in space but also for the efficient and economical operation of various space systems. Electrochemical cells can reduce the mass, volume and logistical penalties associated with resupply and storage by generating and/or consuming these gases in space. An initial flight of the EPICS was conducted aboard STS-69 from September 7 to 8, 1995. A temperature sensor characteristics shift and a missing line of software code resulted in only partial success of this initial flight. Based on the review and recommendations of a National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) review team a reflight activity was initiated to obtain the remaining desired results, not achieved during the initial flight.

  20. Experiment module concepts study. Volume 1: Management summary

    Science.gov (United States)

    1970-01-01

    The minimum number of standardized (common) module concepts that will satisfy the experiment program for manned space stations at least cost is investigated. The module interfaces with other elements such as the space shuttle, ground stations, and the experiments themselves are defined. The total experiment module program resource and test requirements are also considered. The minimum number of common module concepts that will satisfy the program at least cost is found to be three, plus a propulsion slice and certain experiment-peculiar integration hardware. The experiment modules rely on the space station for operational, maintenance, and logistic support. They are compatible with both expendable and shuttle launch vehicles, and with servicing by shuttle, tug, or directly from the space station. A total experiment module program cost of approximately $2319M under the study assumptions is indicated. This total is made up of $838M for experiment module development and production, $806M for experiment equipment, and $675M for interface hardware, experiment integration, launch and flight operations, and program management and support.

  1. Learning in Networks—An Experimental Study Using Stationary Concepts

    Directory of Open Access Journals (Sweden)

    Siegfried K. Berninghaus

    2014-07-01

    Full Text Available Our study analyzes theories of learning for strategic interactions in networks. Participants played two of the 2 × 2 games used by Selten and Chmura [1]. Every participant played against four neighbors. As a distinct aspect our experimental design allows players to choose different strategies against each different neighbor. The games were played in two network structures: a lattice and a circle. We analyze our results with respect to three aspects. We first compare our results with the predictions of five different equilibrium concepts (Nash equilibrium, quantal response equilibrium, action-sampling equilibrium, payoff-sampling equilibrium, and impulse balance equilibrium which represent the long-run equilibrium of a learning process. Secondly, we relate our results to four different learning models (impulse-matching learning, action-sampling learning, self-tuning EWA, and reinforcement learning which are based on the (behavioral round-by-round learning process. At last, we compare the data with the experimental results of Selten and Chmura [1]. One main result is that the majority of players choose the same strategy against each neighbor. As other results, we observe an order of predictive success for the equilibrium concepts that is different from the order shown by Selten and Chmura and an order of predictive success for the learning models that is only slightly different from the order shown in a recent paper by Chmura, Goerg and Selten [2].

  2. Satellite microwave estimates of soil moisture and applications for desertification studies

    Science.gov (United States)

    Owe, Manfred; Van de Griend, Adriaan A.; de Jeu, Richard A.; de Vries, Jorrit; Seyhan, E.

    1998-12-01

    Based on a series of studies conducted in Botswana and preliminary results from an ongoing study in Spain, developments in microwave remote sensing by satellite which can be used to monitor near real-time surface moisture and also study long term soil moisture climatology are described. A progression of methodologies beginning with single polarization studies and leading to both dual polarization and multiple frequency techniques are described. Continuing analysis of a nine year data set of satellite-derived surface moisture in Spain is ongoing. Preliminary results from this study appear to provide some evidence of long term decertification in certain parts of this region. The methodologies developed during these investigations can be applied to other regions, and have the potential for providing modelers with extended data sets of independently derived surface moisture for simulation and validation studies, and climate change studies at the global scale.

  3. Land vehicle antennas for satellite mobile communications

    Science.gov (United States)

    Haddad, H. A.; Pieper, B. V.; Mckenna, D. B.

    1985-01-01

    The RF performance, size, pointing system, and cost were investigated concepts are: for a mechanically steered 1 x 4 tilted microstrip array, a mechanically steered fixed-beam conformal array, and an electronically steered conformal phased array. Emphasis is on the RF performance of the tilted 1 x 4 antenna array and methods for pointing the various antennas studied to a geosynchronous satellite. An updated version of satellite isolations in a two-satellite system is presented. Cost estimates for the antennas in quantities of 10,000 and 100,000 unites are summarized.

  4. Satellite data compression

    CERN Document Server

    Huang, Bormin

    2011-01-01

    Satellite Data Compression covers recent progress in compression techniques for multispectral, hyperspectral and ultra spectral data. A survey of recent advances in the fields of satellite communications, remote sensing and geographical information systems is included. Satellite Data Compression, contributed by leaders in this field, is the first book available on satellite data compression. It covers onboard compression methodology and hardware developments in several space agencies. Case studies are presented on recent advances in satellite data compression techniques via various prediction-

  5. Flood Monitoring and Hydrologic Studies Using Retracked Satellite Radar Altimetry

    Science.gov (United States)

    Zhang, M.; Shum, C.; Lee, H.; Alsdorf, D.; Schwartz, F.

    2008-12-01

    Nadir, pulse-limited radar altimetry measurements have been used to monitor large surface-water bodies. In spite of progress, there is a need for a robust and automated procedure, which allows classification and stage measurements in small water bodies, which lying along the orbital path, using multiple radar altimeter measurements. Here we used an algorithm, which is mainly based on radar scatter waveform response and statistical analysis of mean and standard deviation of the resulting water level change to classify surface- waters from other land covers. We tested the algorithm using 10-Hz retracked radar altimetry measurements from TOPEX over regions including the Amazon River basin, the Prairie Pothole Region in North America, and south-western Taiwan. The estimated water-level stages are compared with data from available stage measurements, and altimetry data available from public data centers. We also applied the algorithm to study the 1997 hundred-year Red River flood, and the June 2008 fifty-year flood in the Upper Midwest of the United States. For the1997 flood, it is found that the flooded regions detected by altimetry include the Red River Basin in North Dakota and Minnesota, the Missouri River Basin in North Dakota and South Dakota, the Minnesota River Basin and the Mississippi River Basin in Minnesota and Iowa. The extent of the flood agrees with the USGS record. The observed water height in Grand Forks reaches 6 meters above the normal. The ENVISAT altimetry is shown to be able to track the ebb and recede of the 2008 Iowa City flood. The results of this study could be applied to provide improved accuracy and potentially automated classification of nadir radar altimetry observed small inland water body measurements for hydrologic studies and for flood monitoring.

  6. A Study of Future Communications Concepts and Technologies for the National Airspace System-Part III

    Science.gov (United States)

    Ponchak, Denise S.; Apaza, Rafael D.; Wichgersm Joel M.; Haynes, Brian; Roy, Aloke

    2014-01-01

    The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) is investigating current and anticipated wireless communications concepts and technologies that the National Airspace System (NAS) may need in the next 50 years. NASA has awarded three NASA Research Announcements (NAR) studies with the objective to determine the most promising candidate technologies for air-to-air and air-to-ground data exchange and analyze their suitability in a post-NextGen NAS environment. This paper will present progress made in the studies and describe the communications challenges and opportunities that have been identified as part of the study. NASA's NextGen Concepts and Technology Development (CTD) Project integrates solutions for a safe, efficient and high-capacity airspace system through joint research efforts and partnerships with other government agencies. The CTD Project is one of two within NASA's Airspace Systems Program and is managed by the NASA Ames Research Center. Research within the CTD Project is in support the 2011 NASA Strategic Plan Sub-Goal 4.1: Develop innovative solutions and advanced technologies, through a balanced research portfolio, to improve current and future air transportation. The focus of CTD is on developing capabilities in traffic flow management, dynamic airspace configuration, separation assurance, super density operations and airport surface operations. Important to its research is the development of human/automation information requirements and decisionmaking guidelines for human-human and human-machine airportal decision-making. Airborne separation, oceanic intrail climb/descent and interval management applications depend on location and intent information of surrounding aircraft. ADS-B has been proposed to provide the information exchange, but other candidates such as satellite-based receivers, broadband or airborne internet, and cellular communications are possible candidate's.

  7. A longitudinal study of perceptions of self-concept and professional self-concept in Turkish nursing students

    Directory of Open Access Journals (Sweden)

    Ayişe Karadağ

    2013-05-01

    Full Text Available This study was conducted to determine the relationship between self-concept and professional self-concept amongst nursing students undertaking a four year degree. A descriptive longitudinal study was applied amongst all nursing students undertaking a four year degree starting in the academic year 2006-2007. The sample consists of total 78 students. The data collection was via two Likert scale type questionnaires about the self description of students and their descriptions of the professional qualities of nurses which were issued a week apart. The first questionnaire consisted of a self-report form of 40 adjectives and students were asked to rate the suitability of each adjective for describing their personality. The second questionnaire employed the same adjectives as the first questionnaire. Students were asked to rate how necessary it was for professional nurses to possess these qualities. SPSS was used to analyse the data via percentages and Cohen’s Kappa method. The data for first year students showed 77.6% were happy to have chosen nursing but significant nearly a quarter were not. 85.9% thought they had similar characteristics to those required by nursing but there was a significant minority of almost one sixth who felt they did not have the required characteristics. The congruence between self-concept and professional self-concept was highest in the fourth year followed by the first year with the second year being the lowest. Congruence between self-concept and professional self-concept across all four years was evident from our study. Some implications of these findings for nursing education and practice are considered. A realistic approach to what is involved in both the study and practice of nursing can increase the self and professional self-concept congruence. It is important for nursing educators to effectively manage student expectations as a better alignment of these with actual situations helps students cope with the demands

  8. Studies of oceanic tectonics based on GEOS-3 satellite altimetry

    Science.gov (United States)

    Poehls, K. A.; Kaula, W. M.; Schubert, G.; Sandwell, D.

    1979-01-01

    Using statistical analysis, geoidal admittance (the relationship between the ocean geoid and seafloor topography) obtained from GEOS-3 altimetry was compared to various model admittances. Analysis of several altimetry tracks in the Pacific Ocean demonstrated a low coherence between altimetry and seafloor topography except where the track crosses active or recent tectonic features. However, global statistical studies using the much larger data base of all available gravimetry showed a positive correlation of oceanic gravity with topography. The oceanic lithosphere was modeled by simultaneously inverting surface wave dispersion, topography, and gravity data. Efforts to incorporate geoid data into the inversion showed that the base of the subchannel can be better resolved with geoid rather than gravity data. Thermomechanical models of seafloor spreading taking into account differing plate velocities, heat source distributions, and rock rheologies were discussed.

  9. An Object Model for Integrating Diverse Remote Sensing Satellite Sensors: A Case Study of Union Operation

    Directory of Open Access Journals (Sweden)

    Chuli Hu

    2014-01-01

    Full Text Available In the Earth Observation sensor web environment, the rapid, accurate, and unified discovery of diverse remote sensing satellite sensors, and their association to yield an integrated solution for a comprehensive response to specific emergency tasks pose considerable challenges. In this study, we propose a remote sensing satellite sensor object model, based on the object-oriented paradigm and the Open Geospatial Consortium Sensor Model Language. The proposed model comprises a set of sensor resource objects. Each object consists of identification, state of resource attribute, and resource method. We implement the proposed attribute state description by applying it to different remote sensors. A real application, involving the observation of floods at the Yangtze River in China, is undertaken. Results indicate that the sensor inquirer can accurately discover qualified satellite sensors in an accurate and unified manner. By implementing the proposed union operation among the retrieved sensors, the inquirer can further determine how the selected sensors can collaboratively complete a specific observation requirement. Therefore, the proposed model provides a reliable foundation for sharing and integrating multiple remote sensing satellite sensors and their observations.

  10. a Detailed Study about Digital Surface Model Generation Using High Resolution Satellite Stereo Imagery

    Science.gov (United States)

    Gong, K.; Fritsch, D.

    2016-06-01

    Photogrammetry is currently in a process of renaissance, caused by the development of dense stereo matching algorithms to provide very dense Digital Surface Models (DSMs). Moreover, satellite sensors have improved to provide sub-meter or even better Ground Sampling Distances (GSD) in recent years. Therefore, the generation of DSM from spaceborne stereo imagery becomes a vivid research area. This paper presents a comprehensive study about the DSM generation of high resolution satellite data and proposes several methods to implement the approach. The bias-compensated Rational Polynomial Coefficients (RPCs) Bundle Block Adjustment is applied to image orientation and the rectification of stereo scenes is realized based on the Project-Trajectory-Based Epipolarity (PTE) Model. Very dense DSMs are generated from WorldView-2 satellite stereo imagery using the dense image matching module of the C/C++ library LibTsgm. We carry out various tests to evaluate the quality of generated DSMs regarding robustness and precision. The results have verified that the presented pipeline of DSM generation from high resolution satellite imagery is applicable, reliable and very promising.

  11. Assessment studies on the inversion of satellite to satellite electron content to obtain electron density profiles in the ionosphere

    CERN Document Server

    Hochegger, G P

    2000-01-01

    The electron content data, obtained by satellite-to-satellite occultations of radio signals can lead to height profiles of electron density by discrete inversion. Since there is no possibility to verify such profiles by means of other measurements (practically never measurements at the same time and same location) it was necessary to simulate occultation scenarios by means of an ionosphere model to obtain a large number of comparisons sufficient for investigations on a statistical basis. The obtained electron contents were inverted and compared with electron density height profiles, obtained with the same ionospheric model for the occultation point. The differences between these profiles were investigated (difference between the F2-peak maxima, the height of the maxima, the shape of the topside and bottom side ionosphere). Since simulations were done for chosen locations (250 randomly spread on the globe) for every month and every second hour and for two solar activity levels (HSA and LSA), a whole year was '...

  12. 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.

  13. Bias adjustment of satellite-based precipitation estimation using gauge observations: A case study in Chile

    Science.gov (United States)

    Yang, Zhongwen; Hsu, Kuolin; Sorooshian, Soroosh; Xu, Xinyi; Braithwaite, Dan; Verbist, Koen M. J.

    2016-04-01

    Satellite-based precipitation estimates (SPEs) are promising alternative precipitation data for climatic and hydrological applications, especially for regions where ground-based observations are limited. However, existing satellite-based rainfall estimations are subject to systematic biases. This study aims to adjust the biases in the Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Cloud Classification System (PERSIANN-CCS) rainfall data over Chile, using gauge observations as reference. A novel bias adjustment framework, termed QM-GW, is proposed based on the nonparametric quantile mapping approach and a Gaussian weighting interpolation scheme. The PERSIANN-CCS precipitation estimates (daily, 0.04°×0.04°) over Chile are adjusted for the period of 2009-2014. The historical data (satellite and gauge) for 2009-2013 are used to calibrate the methodology; nonparametric cumulative distribution functions of satellite and gauge observations are estimated at every 1°×1° box region. One year (2014) of gauge data was used for validation. The results show that the biases of the PERSIANN-CCS precipitation data are effectively reduced. The spatial patterns of adjusted satellite rainfall show high consistency to the gauge observations, with reduced root-mean-square errors and mean biases. The systematic biases of the PERSIANN-CCS precipitation time series, at both monthly and daily scales, are removed. The extended validation also verifies that the proposed approach can be applied to adjust SPEs into the future, without further need for ground-based measurements. This study serves as a valuable reference for the bias adjustment of existing SPEs using gauge observations worldwide.

  14. Study of the Nevada Test Site using Landsat satellite imagery

    Energy Technology Data Exchange (ETDEWEB)

    Zimmerman, P.D. [Georgetown Univ., Washington, DC (United States). Center for Strategic and International Studies

    1993-07-01

    In the period covered by the purchase order CSIS has obtained one Landsat image and determined that two images previously supplied to the principal investigator under a subcontract with George Washington University were inherently defective. We have negotiated with EOSAT over the reprocessing of those scenes and anticipate final delivery within the next few weeks. A critical early purchase during the subcontract period was of an EXABYTE tape drive, Adaptec SCSI interface, and the appropriate software with which to read Landsat images at CSIS. This gives us the capability of reading and manipulating imagery in house without reliance on outside services which have not proven satisfactory. In addition to obtaining imagery for the study, we have also performed considerable analytic work on the newly and previously purchased images. A technique developed under an earlier subcontract for identifying underground nuclear tests at Pahute Mesa has been significantly refined, and similar techniques were applied to the summit of Rainier Mesa and to the Yucca Flats area. An entirely new technique for enhancing the spectral signatures of different regions of NTS was recently developed, and appears to have great promise of success.

  15. 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

  16. The X-Ray Surveyor Mission: A Concept Study

    Science.gov (United States)

    Gaskin, Jessica A.; Weisskopf, Martin C.; Vikhlinin, Alexey; Tananbaum, Harvey D.; Bandler, Simon R.; Bautz, Marshall W.; Burrows, David N.; Falcone, Abraham D.; Harrison, Fiona A.; Heilmann, Ralf K.; Heinz, Sebastian; Hopkins, Randall C.; Kilbourne, Caroline A.; Kouveliotou, Chryssa; Kraft, Ralph P.; Kravtsov, Andrey V.; McEntaffer, Randall L.; Natarajan, Priyamvada; O'Dell, Stephen L.; Petre, Robert; Prieskorn, Zachary R.; Ptak, Andrew F.; Ramsey, Brian D.; Reid, Paul B.; Schnell, Andrew R.; Schwartz, Daniel A.; Townsley, Leisa K.

    2015-01-01

    NASA's Chandra X-ray Observatory continues to provide an unparalleled means for exploring the high-energy universe. With its half-arcsecond angular resolution, Chandra studies have deepened our understanding of galaxy clusters, active galactic nuclei, galaxies, supernova remnants, neutron stars, black holes, and solar system objects. As we look beyond Chandra, it is clear that comparable or even better angular resolution with greatly increased photon throughput is essential to address ever more demanding science questions-such as the formation and growth of black hole seeds at very high redshifts; the emergence of the first galaxy groups; and details of feedback over a large range of scales from galaxies to galaxy clusters. Recently, we initiated a concept study for such a mission, dubbed X-ray Surveyor. The X-ray Surveyor strawman payload is comprised of a high-resolution mirror assembly and an instrument set, which may include an X-ray microcalorimeter, a high-definition imager, and a dispersive grating spectrometer and its readout. The mirror assembly will consist of highly nested, thin, grazing-incidence mirrors, for which a number of technical approaches are currently under development-including adjustable X-ray optics, differential deposition, and new polishing techniques applied to a variety of substrates. This study benefits from previous studies of large missions carried out over the past two decades and, in most areas, points to mission requirements no more stringent than those of Chandra.

  17. Cost-of-illness studies: concepts, scopes, and methods

    Directory of Open Access Journals (Sweden)

    Changik Jo

    2014-12-01

    Full Text Available Liver diseases are one of the main causes of death, and their ever-increasing prevalence is threatening to cause significant damage both to individuals and society as a whole. This damage is especially serious for the economically active population in Korea. From the societal perspective, it is therefore necessary to consider the economic impacts associated with liver diseases, and identify interventions that can reduce the burden of these diseases. The cost-of-illness study is considered to be an essential evaluation technique in health care. By measuring and comparing the economic burdens of diseases to society, such studies can help health-care decision-makers to set up and prioritize health-care policies and interventions. Using economic theories, this paper introduces various study methods that are generally applicable to most disease cases for estimating the costs of illness associated with mortality, morbidity, disability, and other disease characteristics. It also presents concepts and scopes of costs along with different cost categories from different research perspectives in cost estimations. By discussing the epidemiological and economic grounds of the cost-of-illness study, the reported results represent useful information about several evaluation techniques at an advanced level, such as cost-benefit analysis, cost-effectiveness analysis, and cost-utility analysis.

  18. Stereoscopic observations from meteorological satellites

    Science.gov (United States)

    Hasler, A. F.; Mack, R.; Negri, A.

    two satellites. A general solution for accurate height computation depends on precise navigation of the two satellites. Validation of the geosynchronous satellite stereo using high altitude mountain lakes and vertically pointing aircraft lidar leads to a height accuracy estimate of +/- 500 m for typical clouds which have been studied. Applications of the satellite stereo include: 1) cloud top and base height measurements, 2) cloud-wind height assignment, 3) vertical motion estimates for convective clouds (Mack et al. [13], [14]), 4) temperature vs. height measurements when stereo is used together with infrared observations and 5) cloud emissivity measurements when stereo, infrared and temperature sounding are used together (see Szejwach et al. [15]). When true satellite stereo image pairs are not available, synthetic stereo may be generated. The combination of multispectral satellite data using computer produced stereo image pairs is a dramatic example of synthetic stereoscopic display. The classic case uses the combination of infrared and visible data as first demonstrated by Pichel et al. [16]. Hasler et at. [17], Mosher and Young [18] and Lorenz [19], have expanded this concept to display many channels of data from various radiometers as well as real and simulated data fields. A future system of stereoscopic satellites would be comprised of both low orbiters (as suggested by Lorenz and Schmidt [20], [19]) and a global system of geosynchronous satellites. The low earth orbiters would provide stereo coverage day and night and include the poles. An optimum global system of stereoscopic geosynchronous satellites would require international standarization of scan rate and direction, and scan times (synchronization) and resolution of at least 1 km in all imaging channels. A stereoscopic satellite system as suggested here would make an extremely important contribution to the understanding and prediction of the atmosphere.

  19. Satellite Constellations for Space Weather and Ionospheric Studies: Overview of the COSMIC and COSMIC-2 Missions

    Science.gov (United States)

    Schreiner, W. S.; Pedatella, N. M.; Weiss, J.

    2016-12-01

    Measurements from constellations of low Earth orbiting (LEO) satellites are proving highly useful for ionospheric science and space weather studies. The Constellation Observing System for Meteorology Ionosphere and Climate (COSMIC), a joint US/Taiwan mission launched in April 2006, is a six micro-satellite constellation carrying Global Positioning System (GPS) radio occultation (RO) receivers. COSMIC has collected a large amount of useful data from these scientific payloads and is still currently collecting up to 1,000 RO measurement events per day on average. The GPS RO dual-frequency L-band phase and amplitude measurements can be used to observe absolute Total Electron Content (TEC) and scintillation on lines of sight between the LEO and GPS satellites, and electron density profiles via the RO method. The large number and complete global and local time coverage of COSMIC data are allowing scientists to observe ionospheric and plasmaspheric phenomena that are difficult to see with other instruments. The success of COSMIC has prompted U.S. agencies and Taiwan to execute a COSMIC follow-on mission (called COSMIC-2) that will put twelve satellites with GNSS (Global Navigation Satellite System) RO payloads into orbit on two launches in the 2017-20 time frame. The first launch in 2017 will place six satellites in a 520-km altitude 24 deg inclination orbit, which is ideal for low latitude ionospheric research and space weather forecasting. The planned second launch (not currently funded) places six additional satellites in a 750 km 72 deg inclination orbit to provide global coverage and increased sampling density. COSMIC-2 will make use of an advanced radio occultation receiver with an innovative beam-forming antenna design, and is expected to produce at least 10,000 high-quality atmospheric and ionospheric profiles per day from GPS and GLONASS signals to support operational weather prediction, climate monitoring, and space weather forecasting. Each COSMIC-2 spacecraft

  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. NASA Satellite Observations: A Unique Asset for the Study of the Environment and Implications for Public Health

    Science.gov (United States)

    Estes Sue M.

    2010-01-01

    This slide presentation highlights how satellite observation systems are assets for studying the environment in relation to public health. It includes information on current and future satellite observation systems, NASA's public health and safety research, surveillance projects, and NASA's public health partners.

  2. An Integrative Study on Bioinformatics Computing Concepts, Issues and Problems

    Directory of Open Access Journals (Sweden)

    Muhammad Zakarya

    2011-11-01

    Full Text Available Bioinformatics is the permutation and mishmash of biological science and 4IT. The discipline covers every computational tools and techniques used to administer, examine and manipulate huge sets of biological statistics. The discipline also helps in creation of databases to store up and supervise biological statistics, improvement of computer algorithms to find out relations in these databases and use of computer tools for the study and understanding of biological information, including DNA, RNA, protein sequences, gene expression profiles, protein structures, and biochemical pathways. The study of this paper implements an integrative solution. As we know that solution to a problem in a specific discipline may be a solution to another problem in a different discipline. For example entropy that has been rented from physical sciences is solution to most of the problems and issues in computer science. Another example is bioinformatics, where computing method and applications are implemented over biological information. This paper shows an initiative step towards that and will discuss upon the needs for integration of multiple discipline and sciences. Similarly green chemistry gives birth to a new kind of computing i.e. green computing. In next versions of this paper we will study biological fuel cell and will discuss to develop a mobile battery that will be life time charged using the concepts of biological fuel cell. Another issue that we are going to discuss in our series is brain tumor detection. This paper is a review on BI i.e. bioinformatics to start with.

  3. A satellite born charged particles telescope for the study of cosmic ray nuclei

    Energy Technology Data Exchange (ETDEWEB)

    De Pascale, M.P. [Rome Univ. `Tor Vergata` (Italy)]|[INFN, Rome (Italy); Bocciolini, M. [Florence Univ. (Italy)]|[INFN, Florence (Italy); Barbiellini, G.; Boezio, M. [Trieste Univ. (Italy)]|[INFN, Trieste (Italy); Bellotti, R.; Cafagna, F. [Bari Univ. (Italy)]|[INFN, Bari (Italy)

    1995-09-01

    The description of the high energy particle telescope NINA for the study of cosmic ray nuclei is presented. The instrument will be installed on board of the Resource 01 satellite and will fly on a polar orbit at 690 Km. The telescope consists on a pile of 16 detecting planes each of them is composed by two silicon strip detectors with perpendicular strips and has a total area of 60x60mm{sup 2}. The experiment goals are the study of cosmic ray protons and nuclei in the energy range 12-100 MeV/amu. It will be sensitive to the anomalous component and will also make the observation of the large solar flare events and geophysical phenomena as well. This experiment is the first step of the program RIM whose goal is the satellite study of anti particles in primary cosmic rays.

  4. Social Studies Student Teachers' Levels of Understanding Sociology Concepts within Social Studies Curriculum

    Science.gov (United States)

    Karatekin, Kadir

    2013-01-01

    This study aims at investigating social studies student teachers' levels of understanding sociology concepts within social studies curriculum. Study group of the research consists of 266 teacher candidates attending the Department of Social Studies, Faculty of Education, Kastamonu University during 2012 to 2013 education year. A semi-structured…

  5. Social Studies Student Teachers' Levels of Understanding Sociology Concepts within Social Studies Curriculum

    Science.gov (United States)

    Karatekin, Kadir

    2013-01-01

    This study aims at investigating social studies student teachers' levels of understanding sociology concepts within social studies curriculum. Study group of the research consists of 266 teacher candidates attending the Department of Social Studies, Faculty of Education, Kastamonu University during 2012 to 2013 education year. A semi-structured…

  6. Understanding the biological concept "bird": A kindergarten case study

    Science.gov (United States)

    Buchholz, Dilek

    The purpose of this qualitative, multiple case study of 14 students in a metropolitan public school in the Deep South was to find out, during a period of three months, what these kindergarten-aged children knew about birds, whether this knowledge represented current scientific thought, if such science instruction meaningfully affected their prior knowledge, and if so, what the factors during instruction that seemed to influence their understanding of the concept of bird were. The research was conducted in three phases; preinstruction interviews, instruction, and postinstruction interviews. The theoretical framework for this research was based on the Human Constructivism theory of learning (Mintzes, Wandersee and Novak, 1997). Instructional materials consisted of carefully chosen books (both fiction and non-fiction), guest speakers, field trips, a live bird in the classroom, students' observation journals, teacher-made classification and sorting activities, and picture-based concept maps. The findings suggest that young children's knowledge of birds was limited chiefly to birds' anatomical and morphological characteristics, with repeated references being made by the children to human characteristics. There was a positive, significant difference in young children's pre- and postinstruction scientific knowledge of birds. Although performance varied from child to child after instruction, most children were able to identify some common birds by name. Just one child resisted conceptual change. Kindergarten children's basic knowledge of bird behavior was limited to flight and eating. Although the children had more conceptual knowledge at the end, understanding still appeared to be shallow. The children did develop their skill in observing markedly. It also became evident that these kindergarten children needed more (a) experience in asking questions, (b) practice in techniques of visual representation, and (c) language development in order to be able to explain what they

  7. The Logic of Concepts: Case Studies in Engineering and Law

    Science.gov (United States)

    1981-01-01

    the development of the concept of a feedback control system in engineering and the concept of liability for negli- gence to noncontracting parties in...of a feedback control system is an ex- ample from outside of the basic sciences of a paradigm, i.e., a very important and fruitful concept which is...developed from a set of exem- plars and which is taught to others by means of exemplars. Using data from the early development of the feedback control system paradigm

  8. Study on and Redefinition of the Concept of Culture

    Institute of Scientific and Technical Information of China (English)

    戴剑飞

    2015-01-01

    So far, various opinions about the concept of culture are come up with in both China and the West in which three kinds of culture are classified as follows. The culture in narrow sense denotes merely the ideas. The culture in medium sense embraces ideas, customs, norms, symbols and behaviors, etc. The culture in broad sense refers to the lifestyle constituted of both the material culture and spiritual culture. There is an urgent necessity to redefine the concept of culture by exploring the history of the etymolo-gy of the word"culture"in order to figure out the deviance of different concepts of culture.

  9. The paperless labeling initiative: a proof-of-concept study.

    Science.gov (United States)

    Ruchalski, Charles

    2004-01-01

    Traditional paper professional package inserts (PPIs) are used on a daily basis by a variety of healthcare providers to locate and disseminate drug information. Unfortunately, paper PPIs are sometimes not accessible to the healthcare provider, appear unreadable due to varied font sizes, and are often considered not to be user-friendly. In December 2000, the Food and Drug Administration proposed regulations that would revise the format of PPIs. To determine whether electronic delivery of PPI information is achievable in community pharmacy practice settings. Electronic PPIs are an alternative means of delivering this information. This 12-week proof-of-concept study evaluated the Health Information Designs/Thomson Healthcare and Etreby Computer Company for electronic delivery of PPIs in 6 chain and 4 independent community pharmacies, with 5 pharmacies evaluating each system. Participating pharmacists were asked 9 questions designed to determine the feasibility of implementing electronic PPI delivery, as well as pharmacist satisfaction with each system. Pharmacists deemed both systems to be accessible and user-friendly. Pharmacists from both groups felt that the electronic PPIs were challenging to read and that printing took too long. Future studies in a more diverse selection of dispensing sites, including pharmacies (community and hospital based), clinics, and physician practices, need to be performed to maximize the use of electronic PPIs.

  10. · Concept Learning in the Undergraduate Classroom: A Case Study in Religious Studies

    Directory of Open Access Journals (Sweden)

    Jennifer L. Jones

    2014-07-01

    Full Text Available Popularized by the work of Jerome Bruner in the mid-1990’s, the “Concept Attainment Model” is a process of structured inquiry that requires students to make generalizations and draw conclusions from examples (and non-examples of a particular concept toward developing new insights, hypotheses, and associations regarding what they have previously learned (Bruner, 1977. In order to broaden some of the typical assumptions about the manners and conditions in which it can be effectively employed in the undergraduate classroom, this qualitative research study offers an example of the Concept Attainment Model in action in the teaching of traditional just war theory in an undergraduate religion class. Data was collected and analysed according to Spradley’s qualitative research methodologies (Spradley, 1980. Among the most important findings of this study is that in a religion or similar humanities course, the Concept Attainment Model is most likely to find success when highly scaffolded by the instructor.

  11. Satellite communications application to Pacific countries above Ku band

    Science.gov (United States)

    Iida, Takashi

    1992-01-01

    An application of satellite communications above the Ku band to the Pacific region is described, focusing on: (1) Lightsat system and (2) a high capacity satellite system. A small geostationary satellite system using Ku band for the Federated States of Micronesia is shown as an example. A concept of multi-gigabits/second high capacity communications system using two satellites in the Ka band is described. The onboard bit-by-bit processing is very useful in the low link margin environment due to rain attenuation. These topics were obtained by the Asia Pacific Telecommunications Study granted by NASA conducted by the University of Colorado at Boulder.

  12. A general review of concepts for reducing skin friction, including recommendations for future studies

    Science.gov (United States)

    Fischer, M. C.; Ash, R. L.

    1974-01-01

    Four main concepts which have significantly reduced skin friction in experimental studies are discussed; suction, gaseous injection, particle additives, and compliant wall. It is considered possible that each of these concepts could be developed and applied in viable skin friction reduction systems for aircraft application. Problem areas with each concept are discussed, and recommendations for future studies are made.

  13. Loess studies in central United States: Evolution of concepts

    Science.gov (United States)

    Follmer, L.R.

    1996-01-01

    Few words in the realm of earth science have caused more debate than "loess". It is a common term that was first used as a name of a silt deposit before it was defined in a scientific sense. Because this "loose" deposit is easily distinguished from other more coherent deposits, it was recognized as a matter of practical concern and later became the object of much scientific scrutiny. Loess was first recognized along the Rhine Valley in Germany in the 1830s and was first noted in the United States in 1846 along the lower Mississippi River where it later became the center of attention. The use of the name eventually spread around the world, but its use has not been consistently applied. Over the years some interpretations and stratigraphic correlations have been validated, but others have been hotly contested on conceptual grounds and semantic issues. The concept of loess evolved into a complex issue as loess and loess-like deposits were discovered in different parts of the US. The evolution of concepts in the central US developed in four indefinite stages: the eras of (1) discovery and development of hypotheses, (2) conditional acceptance of the eolian origin of loess, (3) "bandwagon" popularity of loess research, and (4) analytical inquiry on the nature of loess. Toward the end of the first era around 1900, the popular opinion on the meaning of the term loess shifted from a lithological sense of loose silt to a lithogenetic sense of eolian silt. However, the dual use of the term fostered a lingering skepticism during the second era that ended in 1944 with an explosion of interest that lasted for more than a decade. In 1944, R.J. Russell proposed and H.N. Fisk defended a new non-eolian, property-based, concept of loess. The eolian advocates reacted with surprise and enthusiasm. Each side used constrained arguments to show their view of the problem, but did not examine the fundamental problem, which was not in the proofs of their hypothesis, but in the definition of

  14. Reusable Reentry Satellite (RRS) system design study. Phase B, appendix E: Attitude control system study

    Science.gov (United States)

    1991-01-01

    A study which consisted of a series of design analyses for an Attitude Control System (ACS) to be incorporated into the Re-usable Re-entry Satellite (RRS) was performed. The main thrust of the study was associated with defining the control laws and estimating the mass and power requirements of the ACS needed to meet the specified performance goals. The analyses concentrated on the different on-orbit control modes which start immediately after the separation of the RRS from the launch vehicle. The three distinct on-orbit modes considered for these analyses are as follows: (1) Mode 1 - A Gravity Gradient (GG) three-axis stabilized spacecraft with active magnetic control; (2) Mode 2 - A GG stabilized mode with a controlled yaw rotation rate ('rotisserie') using three-axis magnetic control and also incorporating a 10 N-m-s momentum wheel along the (Z) yaw axis; and (3) Mode 3 - A spin stabilized mode of operation with the spin about the pitch (Y) axis, incorporating a 20 N-m-s momentum wheel along the pitch (Y) axis and attitude control via thrusters. To investigate the capabilities of the different controllers in these various operational modes, a series of computer simulations and trade-off analyses have been made to evaluate the achievable performance levels, and the necessary mass and power requirements.

  15. Concept Study of Foundation Systems for Wave Energy Converters

    DEFF Research Database (Denmark)

    Molina, Salvador Devant; Vaitkunaite, Evelina; Ibsen, Lars Bo

    Analysis of possible foundation solution for Wave Energy Converters (WEC) is presented by investigating and optimizing novel foundation systems recently developed for offshore wind turbines. Gravity based, pile and bucket foundations are innovative foundation systems that are analyzed. Concept...

  16. Solar power satellite rectenna design study: Directional receiving elements and parallel-series combining analysis

    Science.gov (United States)

    Gutmann, R. J.; Borrego, J. M.

    1978-01-01

    Rectenna conversion efficiencies (RF to dc) approximating 85 percent were demonstrated on a small scale, clearly indicating the feasibility and potential of efficiency of microwave power to dc. The overall cost estimates of the solar power satellite indicate that the baseline rectenna subsystem will be between 25 to 40 percent of the system cost. The directional receiving elements and element extensions were studied, along with power combining evaluation and evaluation extensions.

  17. Study in the Area of Satellite Meteorology. Volume 1. Mesoscale Weather Analysis and Prediction

    Science.gov (United States)

    1974-11-01

    and E. J. Wiegman , "Study of Time-Lapse Processing for Dynamic Hydrologie Conditions," Final Report, NASA Contract NAS5-21841...J. Wiegman , R. G. Hadfield, and W. E. Evans, "Electronic System for Utilization of Satellite Cloud Pictures, " Bull. Amer...Photographs," S~mp Research Paper 71, University of Chicago, Chicago, Ill., 25 pp. (1968). 21. S. M. Serebreny, E. J. Wiegman , R. G. Hadfield, and W. E

  18. Preceptors' conceptions of a peer learning model: A phenomenographic study.

    Science.gov (United States)

    Nygren, Frida; Carlson, Elisabeth

    2017-02-01

    During the past few years nurses precepting undergraduate nursing students have been put under greater pressure because of increased number of students admitted to the universities combined with a shortage of clinical placements. One solution is the preceptor model peer learning where two students are tutored by the same preceptor simultaneously. The aim of this study was to describe the variation of registered nurses' conceptions of preceptorship in a peer learning model for undergraduate nursing students. The study used a qualitative descriptive design and a phenomenographic approach. The interviews took place at somatic and psychiatric units at two different hospitals in southern Sweden. Twelve informants participated who had worked as registered nurses between 1-17years and acted as peer learning preceptors between 2month and 6years. Each nurse was interviewed individually using a semi structured interview guide. Follow up questions were used to make the informants develop and deepen their answers. Four different descriptive categories emerged in the study: 1) Preceptorship in peer learning generates development and new perspectives 2) Preceptorship in peer learning enables student reflection and independence 3) Preceptorship in peer learning engenders insufficiency and stress 4) Preceptorship in peer learning requires education and support. The result of this study showed that preceptors conceived that peer learning enabled them to take a step back which gave them a new role and perspectives. The consequence was that the students could be more independent which saved time for some of the preceptors. However, some preceptors perceived insufficiency and stress while working with two students. It is also important to educate both students and preceptors to optimise the use of peer learning. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Student Teachers' Conceptions about Global Warming and Changes in Their Conceptions during Pre-Service Education: A Cross Sectional Study

    Science.gov (United States)

    Cimer, Sabiha Odabasi; Cimer, Atilla; Ursavas, Nazihan

    2011-01-01

    Global warming is one of the important environmental problems whose dangerous effects are increasing gradually. The study reported herein aimed to reveal student teachers' conceptions about global warming and the effect of biology teacher education program on their awareness of this environmental issue. An open-ended questionnaire was used to…

  20. Student Teachers' Conceptions about Global Warming and Changes in Their Conceptions during Pre-Service Education: A Cross Sectional Study

    Science.gov (United States)

    Cimer, Sabiha Odabasi; Cimer, Atilla; Ursavas, Nazihan

    2011-01-01

    Global warming is one of the important environmental problems whose dangerous effects are increasing gradually. The study reported herein aimed to reveal student teachers' conceptions about global warming and the effect of biology teacher education program on their awareness of this environmental issue. An open-ended questionnaire was used to…

  1. A 220 GHz reflection-type phased array concept study

    Science.gov (United States)

    Hedden, Abigail S.; Dietlein, Charles R.; Wikner, David A.

    2011-05-01

    The goal of this project is to enable light-weight, durable, and portable systems capable of performing standoff detection of person-borne improvised explosive devices (PB-IEDs) through the development of millimeter-wave reflection-type phased arrays. Electronic beam steering eliminates the need for complex mechanical scanners that are commonly implemented with millimeter-wave imaging systems and would reduce overall system size and weight. We present a concept study of a 220 GHz reflection-type phased array for the purpose of performing beam scanning of a confocal reflector system. Requirements for effective imaging of the desired target region are established, including spatial resolution, total scan angle, and number of image pixels achievable. We examine the effects of array architecture on beam characteristics as it is scanned off broadside, including Gaussicity and encircled energy. Benchmark requirements are determined and compared with the capabilities of several potential phase shifter technologies, including MEMS-based variable capacitor phase shifters, switches, and varactor diode-based phase shifters.

  2. Delayed geochemical hazard: Concept, digital model and case study

    Institute of Scientific and Technical Information of China (English)

    CHEN Ming; FENG Liu; Jacques Yvon

    2005-01-01

    Delayed Geochemical Hazard (DGH briefly) presents the whole process of a kind of serious ecological and environmental hazard caused by sudden reactivation and sharp release of long-term accumulated pollutant from stable species to active ones in soil or sediment system due to the change of physical-chemical conditions (such as temperature, pH, Eh, moisture, the concentrations of organic matters, etc.) or the decrease of environment capacity. The characteristics of DGH are discussed. The process of a typical DGH can be expressed as a nonlinear polynomial. The points where the derivative functions of the first and second orders of the polynomial reach zero, minimum and maximum are keys for risk assessment and harzard pridication.The process and mechanism of the hazard is due to the transform of pollutant among different species principally. The concepts of "total releasable content of pollutant", TRCP, and "total concentration of active specie", TCAS, are necessarily defined to describe the mechanism of DGH. The possibility of the temporal and spatial propagation is discussed. Case study shows that there exists a transform mechanism of "gradual release" and "chain reaction" among the species of the exchangeable and the bounds to carbonate, iron and manganese oxides and organic matter, thus causing the delayed geochemical hazard.

  3. Innovative static spectropolarimeter concept for wide spectral ranges: tolerancing study

    CERN Document Server

    Pertenais, Martin; Parès, Laurent; Petit, Pascal

    2015-01-01

    Developing an efficient and robust polarimeter for wide spectral ranges and space applications is a main issue in many projects. As part of the UVMag consortium created to develop UV facilities in space (e.g. the Arago mission proposed to ESA), we are studying an innovative concept of polarimeter that is robust, simple, and efficient on a wide spectral range. The idea, based on the article by Sparks et al. (2012), is to use polarization scramblers to create a spatial modulation of the polarization. Along the height of the wedges of the scramblers, the thickness of the birefringent material crossed by the light, and thus the retardance, vary continuously. This variation creates an intensity modulation of the light related to the entrance polarization state. Analyzing this modulation with a linear polarizer, and dispersing the light spectrally in the orthogonal spatial direction, enables the measurement of the full Stokes vector over the entire spectrum. This determination is performed with a single-shot measur...

  4. Flettner Rotor Concept for Marine Applications: A Systematic Study

    Directory of Open Access Journals (Sweden)

    A. De Marco

    2016-01-01

    Full Text Available The concept of Flettner rotor, a rotating cylinder immersed in a fluid current, with a top-mounted disk, has been analyzed by means of unsteady Reynolds averaged Navier-Stokes simulations, with the aim of creating a suitable tool for the preliminary design of the Flettner rotor as a ship’s auxiliary propulsion system. The simulation has been executed to evaluate the performance sensitivity of the Flettner rotor with respect to systematic variations of several parameters, that is, the spin ratio, the rotor aspect ratio, the effect of the end plates, and their dimensions. The Flettner rotor device has been characterized in terms of lift and drag coefficients, and these data were compared with experimental trends available in literature. A verification study has been conducted in order to evaluate the accuracy of the simulation results and the main sources of numerical uncertainty. All the simulation results were used to achieve a surrogate model of lift and drag coefficients. This model is an effective mathematical tool for the preliminary design of Flettner rotor. Finally, an example of assessment of the Flettner rotor performance as an auxiliary propulsion device on a real tanker ship is reported.

  5. How can present and future satellite missions support scientific studies that address ocean acidification?

    Science.gov (United States)

    Salisbury, Joseph; Vandemark, Douglas; Jonsson, Bror; Balch, William; Chakraborty, Sumit; Lohrenz, Steven; Chapron, Bertrand; Hales, Burke; Mannino, Antonio; Mathis, Jeremy T.; Reul, Nicolas; Signorini, Sergio; Wanninkhof, Rik; Yates, Kimberly K.

    2016-01-01

    Space-based observations offer unique capabilities for studying spatial and temporal dynamics of the upper ocean inorganic carbon cycle and, in turn, supporting research tied to ocean acidification (OA). Satellite sensors measuring sea surface temperature, color, salinity, wind, waves, currents, and sea level enable a fuller understanding of a range of physical, chemical, and biological phenomena that drive regional OA dynamics as well as the potentially varied impacts of carbon cycle change on a broad range of ecosystems. Here, we update and expand on previous work that addresses the benefits of space-based assets for OA and carbonate system studies. Carbonate chemistry and the key processes controlling surface ocean OA variability are reviewed. Synthesis of present satellite data streams and their utility in this arena are discussed, as are opportunities on the horizon for using new satellite sensors with increased spectral, temporal, and/or spatial resolution. We outline applications that include the ability to track the biochemically dynamic nature of water masses, to map coral reefs at higher resolution, to discern functional phytoplankton groups and their relationships to acid perturbations, and to track processes that contribute to acid variation near the land-ocean interface.

  6. Satellite remote sensing of Asian aerosols: a case study of clean, polluted and dust storm days

    Directory of Open Access Journals (Sweden)

    K. H. Lee

    2010-06-01

    Full Text Available Satellite-based aerosol observation is a useful tool for the estimation of microphysical and optical characteristics of aerosol during more than three decades. Until now, a lot of satellite remote sensing techniques have been developed for aerosol detection. In East Asian region, the role of satellite observation is quite important because aerosols originating from natural and man-made pollution in this region have been recognized as an important source for regional and global scale air pollution. However, it is still difficult to retrieve aerosol over land because of the complexity of the surface reflection and complex aerosol composition, in particular, aerosol absorption. In this study, aerosol retrievals using Look-up Table (LUT based method was applied to MODerate Resolution Imaging Spectroradiometer (MODIS Level 1 (L1 calibrated reflectance data to retrieve aerosol optical thickness (AOT over East Asia. Three case studies show how the methodology works to identify those differences to obtain a better AOT retrieval. The comparison between the MODIS and Aerosol Robotic Network (AERONET shows better results when the suggested methodology using the cluster based LUTs is applied (linear slope=0.94, R=0.92 than when operational MODIS aerosol products are used (linear slope=0.78, R=0.87. In conclusion, the suggested methodology is shown to work well with aerosol models acquired by statistical clustering the observation data in East Asia.

  7. A case study in carbon management during the design process Satellite 3, Stansted Airport, UK

    Institute of Scientific and Technical Information of China (English)

    PeterSHARRATT; CamiloDIAZ

    2003-01-01

    Set within the context of China''s growing need to develop a cleaner and more efficient energy supply infrastructure, this paper describes a procurement process for evaluating and reducing the carbon dioxide emissions arising from operational processes within buildings during the design stage when key decisions affecting long-term energy demand are often made but frequently not understood. The focus of the study is a case-study building, the 8275m2 two-storey arrivals/departures building, Satellite 3, at Stansted Airport, UK. The client set a challenging design performance target of a 20% net CO2 reduction below British Airways Authority''s (BAA) current most energy efficient building, Satellite 1, Stansted. This reduction was to be achieved without compromising the BAA corporate standards on passenger and staff comfort perceptions or appreciable increases in capital costs. The carbon assessment methodology involved the following stages:· Establish baseline CO2 footprint and target from real-time energy data for Satellite 1 of 103 kg CO2/m2/a.· Review of the ‘base-case'' building performance assessment for Satellite 3 using BAA''s standard specification criteria.· Assess the impact on energy demand and CO2 emissions of a number of variations to the ‘base-case'' design parameters ranging from solar shading, insulation levels to control systems and occupancy patterns.· Develop an evaluation methodology that iteratively balances capital cost and revenue expenditure with environmental benefits to enable informed choices to be made by the client on where the most ‘environmentally effective'' design responses lie. Outcomes:· A 23% net CO2 reduction by design was achieved at no additional capital cost.· Learning and environmental costs benefit methodology disseminated to the BAA supply chain and adopted at Gatwick and Heathrow Airports. ·CO2 is now a new key performance indicator for design efficiency within BAA.

  8. Changing Concepts in Activity: Descriptive and Design Studies of Consequential Learning in Conceptual Practices

    Science.gov (United States)

    Hall, Rogers; Jurow, A. Susan

    2015-01-01

    Concepts and conceptual change have been studied extensively as phenomena of individual thinking and action, but changing circumstances of social or cultural groups using concepts are treated as external conditions. We describe research on consequential learning in conceptual practices, where concepts include representational infrastructure that…

  9. Study on TT&C resources scheduling technique based on inter-satellite link

    Science.gov (United States)

    Gu, Xiaosong; Bai, Jian; Zhang, Chunze; Gao, Huili

    2014-11-01

    The navigation constellation will have the capability of supporting Tracking Telemetry and Command (TT&C) operations by inter-satellite link (ISL). The ISL will become an important solution to reduce the shortage of ground TT&C resources. The problems need to be studied urgently in the field of space TT&C network resources scheduling management are how to determine the availability of ISL and how to allocate TT&C resources of ISL. The performance and scheduling constraints of navigation constellation's ISL are analyzed, and three utilization strategies of ISL to perform TT&C operations are proposed. The allocation of TT&C resources based on ISL falls into two successive phases. Firstly, master satellite determination equation is established by using 0-1 Programming model based on the availability matrix. Mathematical method is used to solve the equation to determine the master satellite and the topology of ISL. Secondly, Constraint Programming (CP) model is used to describe the ground TT&C resources scheduling problem with special requirements of TT&C operations based on master satellite, and a heuristic algorithm is designed to solve the CP model. The equations and algorithm are verified by simulation examples. The algorithm of TT&C resources scheduling based on ISL has realized the synthesized usage of both the ISL and ground resources on TT&C field. This algorithm can improve TT&C supports of territorial ground TT&C network for global navigation constellation, and provides technical reference for the TT&C mission planning of global constellation by using ISL.

  10. Cyber security with radio frequency interferences mitigation study for satellite systems

    Science.gov (United States)

    Wang, Gang; Wei, Sixiao; Chen, Genshe; Tian, Xin; Shen, Dan; Pham, Khanh; Nguyen, Tien M.; Blasch, Erik

    2016-05-01

    Satellite systems including the Global Navigation Satellite System (GNSS) and the satellite communications (SATCOM) system provide great convenience and utility to human life including emergency response, wide area efficient communications, and effective transportation. Elements of satellite systems incorporate technologies such as navigation with the global positioning system (GPS), satellite digital video broadcasting, and information transmission with a very small aperture terminal (VSAT), etc. The satellite systems importance is growing in prominence with end users' requirement for globally high data rate transmissions; the cost reduction of launching satellites; development of smaller sized satellites including cubesat, nanosat, picosat, and femtosat; and integrating internet services with satellite networks. However, with the promising benefits, challenges remain to fully develop secure and robust satellite systems with pervasive computing and communications. In this paper, we investigate both cyber security and radio frequency (RF) interferences mitigation for satellite systems, and demonstrate that they are not isolated. The action space for both cyber security and RF interferences are firstly summarized for satellite systems, based on which the mitigation schemes for both cyber security and RF interferences are given. A multi-layered satellite systems structure is provided with cross-layer design considering multi-path routing and channel coding, to provide great security and diversity gains for secure and robust satellite systems.

  11. Argus: An Io observer mission concept study from the 2014 NASA/JPL Planetary Science Summer School

    Science.gov (United States)

    Hays, L. E.; Holstein-Rathlou, C.; Becerra, P.; Basu, K.; Davis, B.; Fox, V. K.; Herman, J. F. C.; Hughes, A. C. G.; Keane, J. T.; Marcucci, E.; Mendez-Ramos, E.; Nelessen, A.; Neveu, M.; Parrish, N. L.; Scheinberg, A. L.; Wrobel, J. S.

    2014-12-01

    Jupiter's satellite Io represents the ideal target for studying extreme tidal heating and volcanism, two of the most important processes in the formation and evolution of planetary bodies. The 2011 Planetary Decadal Survey identified an Io Observer as a high-priority New Frontiers class mission to be considered for the decade 2013-2022. In response to the 2009 New Frontiers Announcement of Opportunity, we propose a mission concept for an Io Observer mission, named Argus (after the mythical watchman of Io), developed by the students of the August 2014 session of the Planetary Science Summer School hosted by NASA's Jet Propulsion Laboratory, together with JPL's Team X. The goals of our mission are: (i) Study the effects of tidal heating and its implications for habitability in the Solar System and beyond; (ii) Investigate active lava flows on Io as an analog for early Earth; (iii) Analyze the interaction of Io with the Jovian system through material exchange and magnetospheric activity; (iv) Study the internal structure of Io, as well as its chemical and tectonic history in order to gain insight into its formation and that of the other Galilean satellites.

  12. Identifying Typical Movements Among Indoor Objects - Concepts and Empirical Study

    DEFF Research Database (Denmark)

    Radaelli, Laura; Sabonis, Dovydas; Lu, Hua

    2013-01-01

    indoor moving objects. Specifically, the paper presents a method for the identification of movement patterns. Leveraging concepts from sequential pattern mining, the method takes into account the specifics of spatial movement and, in particular, the specifics of tracking data that captures indoor...

  13. The GIOME: Concept and current role in gastrointestinal tract studies

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ The goal of the Physiome Project is to understand and describe the physiology and pathophysiology of the human organism. Multiscale mathematical and computer models are developed within this concept to help understand human health. From its beginning about 15 years ago, most of the focus has been in the cardiac field (the Cardiome project)but other areas are developing as well now.

  14. Struggling with solutions : a case study of using organisation concepts

    NARCIS (Netherlands)

    Benders, Jos; Slomp, Jannes

    2009-01-01

    Engineers contribute to the constant flow of new tools and organisation concepts. These tend to be presented as solutions to existing organisational problems. These solutions may become problems themselves, however. We present a longitudinal case of how a truck manufacturer struggled with various si

  15. Recent studies in satellite observations of three-dimensional magnetic reconnection

    Institute of Scientific and Technical Information of China (English)

    XIAO ChiJie; WANG XiaoGang; PU ZuYin; MA ZhiWei; ZHAO Hui; ZHOU GuiPing; WANG JingXiu; LIU ZhenXing

    2007-01-01

    Magnetic reconnection is a main process converting the magnetic energy into thermal and kinetic energy in plasmas. It is one of the fundamental problems of crucial importance not only to space plasmas physics and space weather studies,such as the solar flare, coronal mass ejections and magnetospheric substorms, but also to the stability analysis in magnetically confined fusion. In general, except for cases with periodical boundary conditions, three-dimensional (3D) magnetic reconnection occurs on magnetic separatrices generated by magnetic nulls. Here we briefly introduce/review the theories and some recent satellite observations of 3D magnetic reconnection. Topics to be further studied are also discussed.

  16. Monitoring soil wetness variations by means of satellite passive microwave observations: the HYDROPTIMET study cases

    Directory of Open Access Journals (Sweden)

    T. Lacava

    2005-01-01

    Full Text Available Soil moisture is an important component of the hydrological cycle. In the framework of modern flood warning systems, the knowledge of soil moisture is crucial, due to the influence on the soil response in terms of infiltration-runoff. Precipitation-runoff processes, in fact, are related to catchment's hydrological conditions before the precipitation. Thus, an estimation of these conditions is of significant importance to improve the reliability of flood warning systems. Combining such information with other weather-related satellite products (i.e. rain rate estimation might represent a useful exercise in order to improve our capability to handle (and possibly mitigate or prevent hydro-geological hazards. Remote sensing, in the last few years, has supported several techniques for soil moisture/wetness monitoring. Most of the satellite-based techniques use microwave data, thanks to the all-weather and all-time capability of these data, as well as to their high sensitivity to water content in the soil. On the other hand, microwave data are unfortunately highly affected by the presence of surface roughness or vegetation coverage within the instantaneous satellite field of view (IFOV. Those problems, consequently, strongly limit the efficiency and the reliability of traditional satellite techniques. Recently, using data coming from AMSU (Advanced Microwave Sounding Unit, flying aboard NOAA (National Oceanic and Atmospheric Administration satellites, a new methodology for soil wetness estimation has been proposed. The proposed index, called Soil Wetness Variation Index (SWVI, developed by a multi-temporal analysis of AMSU records, seems able to reduce the problems related to vegetation and/or roughness effects. Such an approach has been tested, with promising results, on the analysis of some flooding events which occurred in Europe in the past. In this study, results achieved for the HYDROPTIMET test cases will be analysed and discussed in detail

  17. CMBPol Mission Concept Study: Probing Inflation with CMB Polarization

    CERN Document Server

    Baumann, Daniel; Adshead, Peter; Amblard, Alexandre; Ashoorioon, Amjad; Bartolo, Nicola; Bean, Rachel; Beltran, Maria; de Bernardis, Francesco; Bird, Simeon; Chen, Xingang; Chung, Daniel Jun Hun; Colombo, Loris; Cooray, Asantha R.; Creminelli, Paolo; Dodelson, Scott; Dunkley, Joanna; Dvorkin, Cora; Easther, Richard; Finelli, Fabio; Flauger, Raphael; Hertzberg, Mark P.; Jones-Smith, Katherine; Kachru, Shamit; Kadota, Kenji; Khoury, Justin; Kinney, William H.; Komatsu, Eiichiro; Krauss, Lawrence M.; Lesgourgues, Julien; Liddle, Andrew R.; Liguori, Michele; Lim, Eugene A.; Linde, Andrei D.; Matarrese, Sabino; Mathur, Harsh; McAllister, Liam; Melchiorri, Alessandro; Nicolis, Alberto; Pagano, Luca; Peiris, Hiranya V.; Peloso, Marco; Pogosian, Levon; Pierpaoli, Elena; Riotto, Antonio; Seljak, Uros; Senatore, Leonardo; Shandera, Sarah E.; Silverstein, Eva; Smith, Tristan; Vaudrevange, Pascal M.; Verde, Licia; Wandelt, Ben; Wands, David; Watson, Scott; Wyman, Mark; Yadav, Amit; Valkenburg, Wessel; Zaldarriaga, Matias

    2009-01-01

    We summarize the utility of precise cosmic microwave background (CMB) polarization measurements as probes of the physics of inflation. We focus on the prospects for using CMB measurements to differentiate various inflationary mechanisms. In particular, a detection of primordial B-mode polarization would demonstrate that inflation occurred at a very high energy scale, and that the inflaton traversed a super-Planckian distance in field space. We explain how such a detection or constraint would illuminate aspects of physics at the Planck scale. Moreover, CMB measurements can constrain the scale-dependence and non-Gaussianity of the primordial fluctuations and limit the possibility of a significant isocurvature contribution. Each such limit provides crucial information on the underlying inflationary dynamics. Finally, we quantify these considerations by presenting forecasts for the sensitivities of a future satellite experiment to the inflationary parameters.

  18. STUDIES REGARDING THE CONCEPTION RATES AT DAIRY COWS

    Directory of Open Access Journals (Sweden)

    N. PACALA

    2013-12-01

    Full Text Available The conception rate is defined as the aptitude of a female to romaine pregnant after the first A.I. and represents the proportion between the number of pregnant cows at first A.I and the number of cows inseminated in that period. In our experiments of estrus induction and synchronization, in order to increase the pregnancy rates, we used the Ovsynch protocol and other protocols for PgF2α and GnRH. In order to establish the pregnancy rates, the number of females that have not return in heats after A.I. were taken in consideration. The conception rates were 45.5 – 52.6%. The estrus synchronization offers the possibility to increase the pregnancy rates at first service after calving and creates the possibility to inseminate at certain time without heat detection.

  19. Spacelab software development and integration concepts study report, volume 1

    Science.gov (United States)

    Rose, P. L.; Willis, B. G.

    1973-01-01

    The proposed software guidelines to be followed by the European Space Research Organization in the development of software for the Spacelab being developed for use as a payload for the space shuttle are documented. Concepts, techniques, and tools needed to assure the success of a programming project are defined as they relate to operation of the data management subsystem, support of experiments and space applications, use with ground support equipment, and for integration testing.

  20. Material Identification Technology (MIT) concept technical feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Jones, J.L.; Harker, Y.D.; Yoon, W.Y.; Johnson, L.O.

    1993-09-01

    The Idaho National Engineering Laboratory (INEL) has initiated the design and development of a novel pulsed accelerator-based, active interrogation concept. The proposed concept, referred to as the Material Identification Technology (MIT), enables rapid (between accelerator pulses), non-destructive, elemental composition analysis of both nuclear and non-nuclear materials. Applications of this technique include material monitoring in support of counter-proliferation activities, such as export controls (at domestic and international inspection locations), SNM controls, nuclear weapon dismantlement, and chemical weapon verification. Material Identification Technology combines a pulsed, X-ray source (an electron accelerator) and a gamma detection system. The accelerator must maximize neutron production (pulse width, beam current, beam energy, and repetition rate) and minimize photon dose to the object. Current available accelerator technology can meet these requirements. The detection system must include detectors which provide adequate gamma energy resolution capability, rapid recovery after the initial X-ray interrogation pulse, and multiple single gamma event detection between accelerator pulses. Further research is required to develop the detection system. This report provides the initial feasibility assessment of the MIT concept.

  1. Quantifying offshore wind resources from satellite wind maps: Study area the North Sea

    DEFF Research Database (Denmark)

    Hasager, Charlotte Bay; Barthelmie, Rebecca Jane; Christiansen, Merete B.;

    2006-01-01

    Offshore wind resources are quantified from satellite synthetic aperture radar (SAR) and satellite scatterometer observations at local and regional scale respectively at the Horns Rev site in Denmark. The method for wind resource estimation from satellite observations interfaces with the wind atl...

  2. A Model To Address Design Constraints of Training Delivered via Satellite. Study Number Eight.

    Science.gov (United States)

    Montler, Joseph; Geroy, Gary D.

    This document: summarizes how some companies are addressing the design constraints involved in using satellite technology to deliver training, presents a model aimed at examining cost effectiveness of the satellite option, and includes a guide to designing instructional materials for delivery by satellite. A survey of 39 organizations, 12…

  3. A Study on the Potential Applications of Satellite Data in Air Quality Monitoring and Forecasting

    Science.gov (United States)

    Li, Can; Hsu, N. Christina; Tsay, Si-Chee

    2011-01-01

    In this study we explore the potential applications of MODIS (Moderate Resolution Imaging Spectroradiometer) -like satellite sensors in air quality research for some Asian regions. The MODIS aerosol optical thickness (AOT), NCEP global reanalysis meteorological data, and daily surface PM(sub 10) concentrations over China and Thailand from 2001 to 2009 were analyzed using simple and multiple regression models. The AOT-PM(sub 10) correlation demonstrates substantial seasonal and regional difference, likely reflecting variations in aerosol composition and atmospheric conditions, Meteorological factors, particularly relative humidity, were found to influence the AOT-PM(sub 10) relationship. Their inclusion in regression models leads to more accurate assessment of PM(sub 10) from space borne observations. We further introduced a simple method for employing the satellite data to empirically forecast surface particulate pollution, In general, AOT from the previous day (day 0) is used as a predicator variable, along with the forecasted meteorology for the following day (day 1), to predict the PM(sub 10) level for day 1. The contribution of regional transport is represented by backward trajectories combined with AOT. This method was evaluated through PM(sub 10) hindcasts for 2008-2009, using ohservations from 2005 to 2007 as a training data set to obtain model coefficients. For five big Chinese cities, over 50% of the hindcasts have percentage error less than or equal to 30%. Similar performance was achieved for cities in northern Thailand. The MODIS AOT data are responsible for at least part of the demonstrated forecasting skill. This method can be easily adapted for other regions, but is probably most useful for those having sparse ground monitoring networks or no access to sophisticated deterministic models. We also highlight several existing issues, including some inherent to a regression-based approach as exemplified by a case study for Beijing, Further studies will be

  4. Monitoring Animal Behaviour and Environmental Interactions Using Wireless Sensor Networks, GPS Collars and Satellite Remote Sensing

    National Research Council Canada - National Science Library

    Handcock, Rebecca N; Swain, Dave L; Bishop-Hurley, Greg J; Patison, Kym P; Wark, Tim; Valencia, Philip; Corke, Peter; O'Neill, Christopher J

    2009-01-01

    ...). We explore this concept using a case-study from an extensive cattle enterprise in northern Australia and demonstrate the potential for combining GPS collars and satellite images in a WSN to monitor...

  5. Study of land surface temperature and spectral emissivity using multi-sensor satellite data

    Indian Academy of Sciences (India)

    P K Srivastava; T J Majumdar; Amit K Bhattacharya

    2010-02-01

    In this study, an attempt has been made to estimate land surface temperatures (LST) and spectral emissivities over a hard rock terrain using multi-sensor satellite data. The study area, of about 6000 km2, is a part of Singhbhum–Orissa craton situated in the eastern part of India. TIR data from ASTER, MODIS and Landsat ETM+ have been used in the present study. Telatemp Model AG-42D Portable Infrared Thermometer was used for ground measurements to validate the results derived from satellite (MODIS/ASTER) data. LSTs derived using Landsat ETM+ data of two different dates have been compared with the satellite data (ASTER and MODIS) of those two dates. Various techniques, viz., temperature and emissivity separation (TES) algorithm, gray body adjustment approach in TES algorithm, Split-Window algorithms and Single Channel algorithm along with NDVI based emissivity approach have been used. LSTs derived from bands 31 and 32 of MODIS data using Split-Window algorithms with higher viewing angle (50°) (LST1 and LST2) are found to have closer agreement with ground temperature measurements (ground LST) over waterbody, Dalma forest and Simlipal forest, than that derived from ASTER data (TES with AST 13). However, over agriculture land, there is some uncertainty and difference between the measured and the estimated LSTs for both validation dates for all the derived LSTs. LST obtained using Single Channel algorithm with NDVI based emissivity method in channel 13 of ASTER data has yielded closer agreement with ground measurements recorded over vegetation and mixed lands of low spectral contrast. LST results obtained with TIR band 6 of Landsat ETM+ using Single Channel algorithm show close agreement over Dalma forest, Simlipal forest and waterbody with LSTs obtained using MODIS and ASTER data for a different date. Comparison of LSTs shows good agreement with ground measurements in thermally homogeneous area. However, results in agriculture area with less homogeneity show

  6. Synergy of Satellite-Surface Observations for Studying the Properties of Absorbing Aerosols in Asia

    Science.gov (United States)

    Tsay, Si-Chee

    2010-01-01

    Through interaction with clouds and alteration of the Earth's radiation budget, atmospheric aerosols significantly influence our weather and climate. Monsoon rainfalls, for example, sustain the livelihood of more than half of the world's population. Thus, understanding the mechanism that drives the water cycle and freshwater distribution is high-lighted as one of the major near-term goals in NASA's Earth Science Enterprise Strategy. Every cloud droplet/ice-crystal that serves as an essential element in portraying water cycle and distributing freshwater contains atmospheric aerosols at its core. In addition, the spatial and temporal variability of atmospheric aerosol properties is complex due to their dynamic nature. In fact, the predictability of the tropical climate system is much reduced during the boreal spring, which is associated with the peak season of biomass burning activities and regional/long-range transport of dust aerosols. Therefore, to accurately assess the impact of absorbing aerosols on regional-to-global climate requires not only modeling efforts but also continuous observations from satellites, aircraft, networks of ground-based instruments and dedicated field experiments. Since 1997 NASA has been successfully launching a series of satellites the Earth Observing System - to intensively study, and gain a better understanding of, the Earth as an integrated system. Through participation in many satellite remote-sensing/retrieval and validation projects over the years, we have gradually developed and refined the SMART (Surface-sensing Measurements for Atmospheric Radiative Transfer) and COMMIT (Chemical, Optical & Microphysical Measurements of In-situ Troposphere) mobile observatories, a suite of surface remote sensing and in-situ instruments that proved to be vital in providing high temporal measurements, which complement the satellite observations. In this talk, we will present SMART-COMMIT which has played key roles, serving as network or supersite

  7. 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.

  8. Optimization of post-classification processing of high-resolution satellite image: A case study

    Institute of Scientific and Technical Information of China (English)

    DONG; Rencai; DONG; Jiajia; WU; Gang; DENG; Hongbing

    2006-01-01

    The application of remote sensing monitoring techniques plays a crucial role in evaluating and governing the vast amount of ecological construction projects in China. However, extracting information of ecological engineering target through high-resolution satellite image is arduous due to the unique topography and complicated spatial pattern on the Loess Plateau of China. As a result, enhancing classification accuracy is a huge challenge to high-resolution image processing techniques. Image processing techniques have a definitive effect on image properties and the selection of different parameters may change the final classification accuracy during post-classification processing. The common method of eliminating noise and smoothing image is majority filtering. However, the filter function may modify the original classified image and the final accuracy. The aim of this study is to develop an efficient and accurate post-processing technique for acquiring information of soil and water conservation engineering, on the Loess Plateau of China, using SPOT image with 2.5 rn resolution. We argue that it is vital to optimize satellite image filtering parameters for special areas and purposes, which focus on monitoring ecological construction projects. We want to know how image filtering influences final classified results and which filtering kernel is optimum. The study design used a series of window sizes to filter the original classified image, and then assess the accuracy of each output map and image quality. We measured the relationship between filtering window size and classification accuracy, and optimized the post-processing techniques of SPOT5satellite images. We conclude that (1) smoothing with the majority filter is sensitive to the information accuracy of soil and water conservation engineering, and (2) for SPOT5 2.5 m image, the 5×5 pixel majority filter is most suitable kernel for extracting information of ecological construction sites in the Loess Plateau of

  9. A Comparative Study on Satellite- and Model-Based Crop Phenology in West Africa

    Directory of Open Access Journals (Sweden)

    Elodie Vintrou

    2014-02-01

    Full Text Available Crop phenology is essential for evaluating crop production in the food insecure regions of West Africa. The aim of the paper is to study whether satellite observation of plant phenology are consistent with ground knowledge of crop cycles as expressed in agro-simulations. We used phenological variables from a MODIS Land Cover Dynamics (MCD12Q2 product and examined whether they reproduced the spatio-temporal variability of crop phenological stages in Southern Mali. Furthermore, a validated cereal crop growth model for this region, SARRA-H (System for Regional Analysis of Agro-Climatic Risks, provided precise agronomic information. Remotely-sensed green-up, maturity, senescence and dormancy MODIS dates were extracted for areas previously identified as crops and were compared with simulated leaf area indices (LAI temporal profiles generated using the SARRA-H crop model, which considered the main cropping practices. We studied both spatial (eight sites throughout South Mali during 2007 and temporal (two sites from 2002 to 2008 differences between simulated crop cycles and determined how the differences were indicated in satellite-derived phenometrics. The spatial comparison of the phenological indicator observations and simulations showed mainly that (i the satellite-derived start-of-season (SOS was detected approximately 30 days before the model-derived SOS; and (ii the satellite-derived end-of-season (EOS was typically detected 40 days after the model-derived EOS. Studying the inter-annual difference, we verified that the mean bias was globally consistent for different climatic conditions. Therefore, the land cover dynamics derived from the MODIS time series can reproduce the spatial and temporal variability of different start-of-season and end-of-season crop species. In particular, we recommend simultaneously using start-of-season phenometrics with crop models for yield forecasting to complement commonly used climate data and provide a better

  10. Concept Study: Exploration and Production in Environmentally Sensitive Arctic Areas

    Energy Technology Data Exchange (ETDEWEB)

    Shirish Patil; Rich Haut; Tom Williams; Yuri Shur; Mikhail Kanevskiy; Cathy Hanks; Michael Lilly

    2008-12-31

    The Alaska North Slope offers one of the best prospects for increasing U.S. domestic oil and gas production. However, this region faces some of the greatest environmental and logistical challenges to oil and gas production in the world. A number of studies have shown that weather patterns in this region are warming, and the number of days the tundra surface is adequately frozen for tundra travel each year has declined. Operators are not allowed to explore in undeveloped areas until the tundra is sufficiently frozen and adequate snow cover is present. Spring breakup then forces rapid evacuation of the area prior to snowmelt. Using the best available methods, exploration in remote arctic areas can take up to three years to identify a commercial discovery, and then years to build the infrastructure to develop and produce. This makes new exploration costly. It also increases the costs of maintaining field infrastructure, pipeline inspections, and environmental restoration efforts. New technologies are needed, or oil and gas resources may never be developed outside limited exploration stepouts from existing infrastructure. Industry has identified certain low-impact technologies suitable for operations, and has made improvements to reduce the footprint and impact on the environment. Additional improvements are needed for exploration and economic field development and end-of-field restoration. One operator-Anadarko Petroleum Corporation-built a prototype platform for drilling wells in the Arctic that is elevated, modular, and mobile. The system was tested while drilling one of the first hydrate exploration wells in Alaska during 2003-2004. This technology was identified as a potentially enabling technology by the ongoing Joint Industry Program (JIP) Environmentally Friendly Drilling (EFD) program. The EFD is headed by Texas A&M University and the Houston Advanced Research Center (HARC), and is co-funded by the National Energy Technology Laboratory (NETL). The EFD

  11. Study of a Novel Concept for a Liquid Argon Calorimeter \

    CERN Multimedia

    2002-01-01

    % RD33 \\\\ \\\\ The development of a fast, highly granular and compact electromagnetic liquid argon calorimeter prototype is proposed as a generic R\\&D project for a novel concept of calorimetry in proton-proton and electron-positron collider detectors: the $^{\\prime$Thin Gap Turbine$^{\\prime}$ (TGT). The TGT calorimeter has a modular construction, is flexible in its longitudinal and transverse granularity, and offers a uniform energy response and resolution, independent of the production angle of incident particles. An important aspect of the project is the development of fast, radiation-hard front-end electronics which is operating in the cold.

  12. Preliminary study on migration pattern of the Tibetan antelope ( Pantholops hodgsonii) based on satellite tracking

    Science.gov (United States)

    Buho, Hoshino; Jiang, Z.; Liu, C.; Yoshida, T.; Mahamut, Halik; Kaneko, M.; Asakawa, M.; Motokawa, M.; Kaji, K.; Wu, X.; Otaishi, N.; Ganzorig, Sumiya; Masuda, R.

    2011-07-01

    The spatial and temporal patterns of the endangered Tibetan antelope or chiru ( Pantholops hodgsonii) have been studied using satellite-based ARGOS platform transmitter terminal (PTT) tracking data. The data was obtained from the satellite tracking of two female Tibetan antelopes that were collared with satellite transmitters and have been tracked from August 2007 to April 2009. Analysis of the locality data (LC) obtained, shows that both antelopes were migrant individuals, they shared the same calving ground surrounding lake Huiten (or Zhuonai lake), but different wintering pastures. Each antelope covered 250-300 km from the wintering to summer pastures. Annual range consisted of a core area that was used for at least 9 months; a calving ground used for a short time (from 8-20 days); and temporal pastures used during migration to and from the calving ground. Seasonal migration cycle was about 3 months, 27-30 days to reach the calving ground; 8-20 days staying there; and 36-40 days returning to the core area. Examination of the spatial distribution during migration showed that both chiru crossed the Qinghai-Tibetan railway (QTR) and the Golmud-Lhasa highway (GLH) at least two times, and reached calving ground (118-120 km from there) in 8 days, maintaining an average speed of 15 km per day. However, the return migration took twice as long (from 14 to 16 days). Each time, after reaching the QTR and GLH, the antelopes spent 20-40 days in that area, probably looking for passages and waiting. So far, we suppose that the QTR and the GLH have become a hindrance to the migration of the Tibetan antelopes and seriously delay their movement to and from the calving area. Extended aggregation of the herds of Tibetan antelopes along the QTR and the GLH may impact negatively with increased mortality among offspring, the spread of various diseases and overgrazing of pastures.

  13. Gold Minerogenetic Prognosis Using Satellite Data: Case Study of Paishanlou Gold Mine, Liaoning Province, China

    Institute of Scientific and Technical Information of China (English)

    Malogo J M Kongola; Wang Ende

    2005-01-01

    The major scientific goal of using satellite data for mineral prospecting in the study area was two-fold: (a) mapping geology, faults and fractures that localize ore deposits; (b) recognizing hydrothermally altered rocks by interpreting their spectral signatures. The lithology, properties, and geological relations of the rocks were key to understanding such varied phenomena as convection, melting and transport mechanisms, rock deformation and alteration, the sources of magnetic anomalies, and the hydrothermal circulation and formation of gold deposits. Satellite data were enhanced using the following techniques: band combinations, ratios, directional sharpening filtering, Laplacian transform, spatial convolution, and density slicing. By mapping a larger area, the Paishanlou Gold Mine was discovered to be located within an accommodation zone, with three significant populations of faults having bearings of 95, 145, and 180 degrees. Faults bearing 145 degrees make up the faults of the main shear zone. The faults bearing 180 degrees have large sinistral offsets, typically 1.5 km, and form a synthetic-antithetic set with the faults bearing 145 degrees, which have dextral displacements of tens of meters. In the Landsat ETM+ image composed of bands 7-4-2 RGB, gneiss rocks were clearly seen as red purple, and granitic and plagioclase bodies in pale brown/pink. The strongest alteration signature in the image was found along the detachment fault antiform located closest to the mine and the plutons responsible for the Paishanlou gold mineralization. Satellite image interpretation coupled with field surveys led to the identification of iron mineral composites, hydrothermally altered areas, fractures, and an accommodation zone. These anomalies finally resulted in the discovery of three new gold-mineralized sites.

  14. A Study on Contingency Learning in Introductory Physics Concepts

    Science.gov (United States)

    Scaife, Thomas M.

    Instructors of physics often use examples to illustrate new or complex physical concepts to students. For any particular concept, there are an infinite number of examples, thus presenting instructors with a difficult question whenever they wish to use one in their teaching: which example will most effectively illustrate the concept so that student learning is maximized? The choice is typically made by an intuitive assumption about which exact example will result in the most lucid illustration and the greatest student improvement. By questioning 583 students in four experiments, I examined a more principled approach to example selection. By controlling the manner in which physical dimensions vary, the parameter space of each concept can be divided into a discrete number of example categories. The effects of training with members of each of category was explored in two different physical contexts: projectile motion and torque. In the first context, students were shown two trajectories and asked to determine which represented the longer time of flight. Height, range, and time of flight were the physical dimensions that were used to categorize the examples. In the second context, students were shown a balance-scale with loads of differing masses placed at differing positions along either side of the balance-arm. Mass, lever-arm length, and torque were the physical dimensions used to categorize these examples. For both contexts, examples were chosen so that one or two independent dimensions were varied. After receiving training with examples from specific categories, students were tested with questions from all question categories. Successful training or instruction can be measured either as producing correct, expert-like behavior (as observed through answers to the questions) or as explicitly instilling an understanding of the underlying rule that governs a physical phenomenon. A student's behavior might not be consistent with their explicit rule, so following the

  15. Black adolescents: a descriptive study of their self-concepts and academic achievement.

    Science.gov (United States)

    Mboya, M M

    1986-01-01

    This study was designed to determine the relationships among global self-concept, self-concept of academic ability, and academic achievement of black American adolescents. The subjects were 211 tenth-grade students in five public high schools in the Pacific Northwest school district who volunteered to participate in the study. Global self-concept was measured by the Coopersmith Self-Esteem Inventory (SEI), self-concept of academic ability by the Brookover Self-Concept of Ability (General) Scale, and academic achievement by the California Achievement Test (CAT). The major statistical tools were the Pearson product-moment correlations and Fisher Z statistic. In all of the tests the decision was made to reject the null hypothesis at the .05 level of significance. No significant relationship was found between global self-concept and academic achievement, although the relationship between self-concept of academic ability and academic achievement reached significance. The relationship between self-concept of academic ability and academic achievement correlated more strongly than the relationship between global self-concept and academic achievement. These results suggest that the enhancement of global self-concept might not be a potent intervention for academic improvement for black adolescents.

  16. A satellite based study of tropospheric bromine explosion events and their linkages to polar cyclone development

    Science.gov (United States)

    Blechschmidt, Anne-Marlene; Richter, Andreas; Burrows, John P.; Kaleschke, Lars; Strong, Kimberly; Theys, Nicolas; Weber, Mark; Zhao, Xiaoyi; Zien, Achim; Hodges, Kevin I.

    2016-04-01

    Intense, cyclone-like shaped plumes of tropospheric bromine monoxide (BrO) are regularly observed by the UV-vis satellite instruments GOME-2/MetOp-A and SCIAMACHY/Envisat over Arctic and Antarctic sea ice in polar spring. The plumes are associated with an autocatalytic chemical chain reaction involving tropospheric ozone depletion and initiated by the release of bromine from cold brine-covered ice or snow to the atmosphere. This influences atmospheric chemistry as it affects the oxidising capacity of the troposphere through OH production and may also influence the local weather/temperature of the polar atmosphere, as ozone is a major greenhouse gas. Here, we make combined use of satellite retrievals and numerical model simulations to study individual BrO plume cases in the polar atmosphere. In agreement with previous studies, our analysis shows that the plumes are often transported by high latitude cyclones, sometimes over several days despite the short atmospheric lifetime of BrO. Moreover, general characteristics of bromine explosion events linked to transport by polar weather systems, such as frequency, spatial distribution and favourable weather conditions are derived based on a new detection method. Our results show that BrO cyclone transport events are by far more common in the Antarctic than in the Arctic.

  17. 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.

  18. A Longitudinal Study of Depressive Symptomology and Self-Concept in Adolescents

    Science.gov (United States)

    Montague, Marjorie; Enders, Craig; Dietz, Samantha; Dixon, Jennifer; Cavendish, Wendy Morrison

    2008-01-01

    The purpose of the study was to investigate the trajectories of depressive symptomology and self-concept in adolescents between the ages of 13 and 17 and to determine whether primary school teacher ratings of adaptive and maladaptive behavior predict self-reported depressive symptoms and self-concept in adolescence. This study is part of an…

  19. Quality and Rigor of the Concept Mapping Methodology: A Pooled Study Analysis

    Science.gov (United States)

    Rosas, Scott R.; Kane, Mary

    2012-01-01

    The use of concept mapping in research and evaluation has expanded dramatically over the past 20 years. Researchers in academic, organizational, and community-based settings have applied concept mapping successfully without the benefit of systematic analyses across studies to identify the features of a methodologically sound study. Quantitative…

  20. Intermediality in early cinema studies: An interrogation of a widely used concept for research practice

    NARCIS (Netherlands)

    Dellmann, S.; Ruppin, D.; de Zwaan, K.

    2012-01-01

    The authors discuss the concept of intermediality for research in early cinema. After a general introduction to intermediality as research problem in media studies, the question is raised whether the concept of intermediality can be used in diachronic research designs and for media studies that deal

  1. CO2 laser as a possible candidate for optical transmitter in free-space satellite-ground-satellite laser communication: a case study

    Science.gov (United States)

    Kumar, M. A.; Naik, Govind; Shenoy, N. V.; Rao, Mandavilli M.

    1999-04-01

    Terrestrial fiber optic communication systems handle most of the inter-continental communication systems today. However recent studies indicate that these links, in spite of their huge bandwidth will be saturated in the near future. Hence attempts are being made is augment and may be even replace these by inter satellite links (ISLs). Though high power laser diodes have been found to be suitable for ISLs, they are unfortunately inadequate for satellite-ground links (SGL and GSL) as they are not powerful enough. So we have to look for more powerful lasers for SGLs & GSLs. One possible candidate is the CO2 laser. It is a gas laser. It provides a number of advantages over other sources. They include high life time, high efficiency and stability. Besides it can generate a high power continuous wave and requires only radiative cooling. CO2 can provide a high bit rate and long range transmission with low bit error rate. Also CO2 laser is in near infra-red and hence the turbulence effects due to clouds is minimum. All these make CO2 laser a very economical choice. The use of optical communication in GSLs provides many advantages over radio links. Laser being a high energy source provides the advantage of greater bandwidth, smaller beam divergence angles, smaller antennae, greater security and a new spectrum. Lesser power consumption and smaller size make it more suitable for use in a satellite. The present paper deals with a case study of a CO2 laser based free space optical communication link by making the link budget analysis.

  2. Study on distributed generation algorithm of variable precision concept lattice based on ontology heterogeneous database

    Science.gov (United States)

    WANG, Qingrong; ZHU, Changfeng

    2017-06-01

    Integration of distributed heterogeneous data sources is the key issues under the big data applications. In this paper the strategy of variable precision is introduced to the concept lattice, and the one-to-one mapping mode of variable precision concept lattice and ontology concept lattice is constructed to produce the local ontology by constructing the variable precision concept lattice for each subsystem, and the distributed generation algorithm of variable precision concept lattice based on ontology heterogeneous database is proposed to draw support from the special relationship between concept lattice and ontology construction. Finally, based on the standard of main concept lattice of the existing heterogeneous database generated, a case study has been carried out in order to testify the feasibility and validity of this algorithm, and the differences between the main concept lattice and the standard concept lattice are compared. Analysis results show that this algorithm above-mentioned can automatically process the construction process of distributed concept lattice under the heterogeneous data sources.

  3. Sampling errors for satellite-derived tropical rainfall - Monte Carlo study using a space-time stochastic model

    Science.gov (United States)

    Bell, Thomas L.; Abdullah, A.; Martin, Russell L.; North, Gerald R.

    1990-01-01

    Estimates of monthly average rainfall based on satellite observations from a low earth orbit will differ from the true monthly average because the satellite observes a given area only intermittently. This sampling error inherent in satellite monitoring of rainfall would occur even if the satellite instruments could measure rainfall perfectly. The size of this error is estimated for a satellite system being studied at NASA, the Tropical Rainfall Measuring Mission (TRMM). First, the statistical description of rainfall on scales from 1 to 1000 km is examined in detail, based on rainfall data from the Global Atmospheric Research Project Atlantic Tropical Experiment (GATE). A TRMM-like satellite is flown over a two-dimensional time-evolving simulation of rainfall using a stochastic model with statistics tuned to agree with GATE statistics. The distribution of sampling errors found from many months of simulated observations is found to be nearly normal, even though the distribution of area-averaged rainfall is far from normal. For a range of orbits likely to be employed in TRMM, sampling error is found to be less than 10 percent of the mean for rainfall averaged over a 500 x 500 sq km area.

  4. Study of the triple-mass Tethered Satellite System under aerodynamic drag and J2 perturbations

    Science.gov (United States)

    Razzaghi, Pourya; Assadian, Nima

    2015-11-01

    The dynamics of multi-tethered satellite formations consisting of three masses are studied in this paper. The triple-mass triple-tethered satellite system is modeled under the low Earth orbit perturbations of drag and Earth's oblateness and its equilibrium conditions are derived. It is modeled as three equal end-masses connected by a uniform-mass straight tether. The lengths of tethers are supposed to be constant and in this manner the angles of the plane consisting the masses are taken as the state variables of the system. The governing equations of motion are derived using Lagrangian approach. The aerodynamic drag perturbation is expressed as an external non-conservative force and the Earth oblateness (J2 perturbation) is considered as a term of potential energy. The equilibrium conditions of this system are found and their stability is investigated through the linear stability theory. Then, the results are verified by using a nonlinear simulation for three types of equilibrium conditions.

  5. Satellite-based Studies on Large-Scale Vegetation Changes in China

    Institute of Scientific and Technical Information of China (English)

    Xia Zhao; Daojing Zhou; Jingyun Fang

    2012-01-01

    Remotely-sensed vegetation indices,which indicate the density and photosynthetic capacity of vegetation,have been widely used to monitor vegetation dynamics over broad areas.In this paper,we reviewed satellite-based studies on vegetation cover changes,biomass and productivity variations,phenological dynamics,desertification,and grassland degradation in China that occurred over the past 2-3 decades.Our review shows that the satellite-derived index (Normalized Difference Vegetation Index,NDVI) during growing season and the vegetation net primary productivity in major terrestrial ecosystems (for example forests,grasslands,shrubs,and croplands) have significantly increased,while the number of fresh lakes and vegetation coverage in urban regions have experienced a substantial decline.The start of the growing season continually advanced in China's temperate regions until the 1990s,with a large spatial heterogeneity.We also found that the coverage of sparsely-vegetated areas declined,and the NDVI per unit in vegetated areas increased in arid and semi-arid regions because of increased vegetation activity in grassland and oasis areas.However,these results depend strongly not only on the periods chosen for investigation,but also on factors such as data sources,changes in detection methods,and geospatial heterogeneity.Therefore,we should be cautious when applying remote sensing techniques to monitor vegetation structures,functions,and changes.

  6. Autoionization study of the Argon 2p satellites excited near the argon 2s threshold

    Energy Technology Data Exchange (ETDEWEB)

    Wang, H.; Glans, P.; Hemmers, O. [Univ. of Nevada, Las Vegas, NV (United States)] [and others

    1997-04-01

    The dynamics of near-threshold photoionization is a complex phenomenon in which the many-electron character of the wavefunctions plays an important role. According to generalized time-independent resonant scattering theory, the transition matrix element from an initial state to a final state is the summation of the amplitudes of direct photoionization and an indirect term in which intermediate states are involved and the resonant behavior is embedded. Studies of the interference effects of intermediate states have been explored in the cases where the direct term is negligible. In the present work, electron time-of-flight spectra of the Ar 2p satellites were measured at two angles (magic and 0{degrees}) in the dipole plane with the exciting photon energy tuned in the vicinity of the Ar 2s threshold. For excitation far below or above the 2s threshold, the 2p satellites spectrum is dominated by 3p to np shakeup contributions upon the ionization of a 2p electron.

  7. On self-boundary: a study of the development of the concept of secrecy.

    Science.gov (United States)

    Meares, R; Orlay, W

    1988-12-01

    The child's developing concept of a 'boundary' between an inner world of 'self' and an outer world 'non-self' is central to a number of systems of psychodynamic theory. The notion of boundary is also essential to Piaget. Despite the evident importance of the subject, there have been few attempts to discover the age at which this concept emerges. This study of 40 urban Australian children uses the development of the concept of secrecy as a marker. Most children attained this concept during the fifth year of life.

  8. The study of gravity gradient effect on attitude of low earth orbit satellite

    Science.gov (United States)

    Hamzah, Nor Hazadura; Yaacob, Sazali; Muthusamy, Hariharan; Hamzah, Norhizam; Ghazali, Najah

    2013-04-01

    Simulations and mathematical models are increasingly used to assist the process of decision making in engineering design. The objective of this paper is to simulate the linear attitude dynamics of small satellites under gravity gradient torque which is inherent in low earth orbit. The equations were first derived in their nonlinear form, and then manipulated and simulated in their linear form. Simulation results demonstrate the importance of choosing the appropriate values of satellite's moment of inertia in designing phase of a satellite.

  9. Using Satellite Imagery to Monitor the Major Lakes; Case Study Lake Hamun

    Science.gov (United States)

    Norouzi, H.; Islam, R.; Bah, A.; AghaKouchak, A.

    2015-12-01

    Proper lakes function can ease the impact of floods and drought especially in arid and semi-arid regions. They are important environmentally and can directly affect human lives. Better understanding of the effect of climate change and human-driven changes on lakes would provide invaluable information for policy-makers and local people. As part of a comprehensive study, we aim to monitor the land-cover/ land-use changes in the world's major lakes using satellite observations. As a case study, Hamun Lake which is a pluvial Lake, also known as shallow Lake, located on the south-east of Iran and adjacent to Afghanistan, and Pakistan borders is investigated. The Lake is the main source of resources (agriculture, fishing and hunting) for the people around it and politically important in the region since it is shared among three different countries. The purpose of the research is to find the Lake's area from 1972 to 2015 and to see if any drought or water resources management has affected the lake. Analyzing satellites imagery from Landsat shows that the area of the Lake changes seasonally and intra-annually. Significant seasonal effects are found in 1975,1977, 1987, 1993, 1996, 1998, 2000, 2009 and 2011, as well as, substantial amount of shallow water is found throughout the years. The precipitation records as well as drought historical records are studied for the lake's basin. Meteorological studies suggest that the drought, decrease of rainfalls in the province and the improper management of the Lake have caused environmental, economic and geographical consequences. The results reveal that lake has experienced at least two prolong dryings since 1972 which drought cannot solely be blamed as main forcing factor.Proper lakes function can ease the impact of floods and drought especially in arid and semi-arid regions. They are important environmentally and can directly affect human lives. Better understanding of the effect of climate change and human-driven changes on lakes

  10. Recent studies in satellite observations of three-dimensional magnetic reconnection

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Magnetic reconnection is a main process converting the magnetic energy into thermal and kinetic energy in plasmas. It is one of the fundamental problems of crucial importance not only to space plasmas physics and space weather studies,such as the solar flare,coronal mass ejections and magnetospheric substorms,but also to the stability analysis in magnetically confined fusion. In general,except for cases with periodical boundary conditions,three-dimensional(3D) magnetic re-connection occurs on magnetic separatrices generated by magnetic nulls. Here we briefly introduce/review the theories and some recent satellite observations of 3D magnetic reconnection. Topics to be further studied are also discussed.

  11. Developing a Satellite Based Automatic System for Crop Monitoring: Kenya's Great Rift Valley, A Case Study

    Science.gov (United States)

    Lucciani, Roberto; Laneve, Giovanni; Jahjah, Munzer; Mito, Collins

    2016-08-01

    The crop growth stage represents essential information for agricultural areas management. In this study we investigate the feasibility of a tool based on remotely sensed satellite (Landsat 8) imagery, capable of automatically classify crop fields and how much resolution enhancement based on pan-sharpening techniques and phenological information extraction, useful to create decision rules that allow to identify semantic class to assign to an object, can effectively support the classification process. Moreover we investigate the opportunity to extract vegetation health status information from remotely sensed assessment of the equivalent water thickness (EWT). Our case study is the Kenya's Great Rift valley, in this area a ground truth campaign was conducted during August 2015 in order to collect crop fields GPS measurements, leaf area index (LAI) and chlorophyll samples.

  12. Conceptual design study advanced concepts test (ACT) facility

    Energy Technology Data Exchange (ETDEWEB)

    Zaloudek, F.R.

    1978-09-01

    The Advanced Concepts Test (ACT) Project is part of program for developing improved power plant dry cooling systems in which ammonia is used as a heat transfer fluid between the power plant and the heat rejection tower. The test facility will be designed to condense 60,000 lb/hr of exhaust steam from the No. 1 turbine in the Kern Power Plant at Bakersfield, CA, transport the heat of condensation from the condenser to the cooling tower by an ammonia phase-change heat transport system, and dissipate this heat to the environs by a dry/wet deluge tower. The design and construction of the test facility will be the responsibility of the Electric Power Research Institute. The DOE, UCC/Linde, and the Pacific Northwest Laboratories will be involved in other phases of the project. The planned test facilities, its structures, mechanical and electrical equipment, control systems, codes and standards, decommissioning requirements, safety and environmental aspects, and energy impact are described. Six appendices of related information are included. (LCL)

  13. Student nurses' conceptions of internationalization: a phenomenographic study.

    Science.gov (United States)

    Wihlborg, M

    1999-10-01

    A phenomenographic approach was used when analysing and interpreting interviews with 25 student nurses in order to describe their conceptions of internationalization. The results are presented in five categories and various subcategories, forming an outcome space. The categories describe forms of understanding, or ways of thinking about internationalization, which, in relation to internationalization as a whole, were either atomistic or holistic in character. The data revealed that nursing students shared some aspects of meaning when thinking of internationalization. These aspects seemed to be understood in a similar way by all students, whereas, when students thought about internationalization as a whole, they assigned it different meanings. In two of the categories aspects of meaning were fragmentarily related to each other, and represented only one perspective. These two categories are to be compared to the other three categories which were more complex and holistic in character, since they contained more than one perspective as well as more aspects of meaning, and related in several different ways. From a pedagogical point of view, the findings point to the importance of teachers trying, in an active way, to confront students with as many existing variations of conceptualized wholes related to internationalization as possible, by using forms of understanding originating from a holistic approach.

  14. Study on Overall Concept Planning of Terminal Correction Mortar Projectiles

    Institute of Scientific and Technical Information of China (English)

    XU Jin-xiang

    2008-01-01

    The system composition, the operational principle of terminal correction mortar projectiles (TCMP) and the concept planning design of TCMP are researched in this paper. An overall design and aerodynamic configuration layout for TCMP are made in this paper, and its aerodynamic coefficients are calculated by using computational fluid dynamics (CFD) software. Test results of TCMP simulated ballistic projectiles indicate the designed TCMP can satisfy the interior ballistic demand and has a fine flight stability. The drag coefficients identified from the radar velocity-time data are in accord with the CFD computed results. According to the exposure frequency of the ground laser designator, a four-quadrant impulse correction scheme and a high exposure frequency impulse correction scheme are brought. The latter can calculate the target azimuth angle by counting the times of the facula passing through one quadrant. Simulation results also show that the guidance precision of the velocity pursuit is higher than that of the body pursuit, and the detector axis is less circuitous. Researches on the typical trajectory indicate that the terminal impulse correction can improve the hit precision of TCMP remarkably.

  15. 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...

  16. Alternative Conceptions in Animal Classification Focusing on Amphibians and Reptiles: A Cross-Age Study

    Science.gov (United States)

    Yen, Chiung-Fen; Yao, Tsung-Wei; Chiu, Yu-Chih

    2004-01-01

    This study examined students' alternative conceptions of reptiles and amphibians and the extent to which these conceptions remain intact through the elementary (grades 4 and 6), junior, and senior high school years. We administered multiple-choice and free-response instruments to a total of 513 students and interviewed at least 20 students at each…

  17. Teaching L2 Spanish Sociopragmatics through Concepts: A Classroom-Based Study

    Science.gov (United States)

    van Compernolle, Rémi A.; Gomez-Laich, Maria Pia; Weber, Ashley

    2016-01-01

    This study explores the teaching of second language (L2) Spanish sociopragmatics through concept-based pragmatics instruction (van Compernolle, 2014). The concepts of self-presentation, social distance, and power were the focus of a pedagogical enrichment program in 2 sections of a beginning-level Spanish class at a northeastern U.S. university.…

  18. Conceptions of happiness and life satisfaction: An exploratory study in 14 national groups

    NARCIS (Netherlands)

    Joshanloo, Mohsen; Rizwan, Muhammad; Khilji, Imran Ahmed; Ferreira, Maria Cristina; Poon, Wai-Ching; Sundaram, Suresh; Ho, Lok Sang; Yeung, Victoria Wai Lan; Han, Gyuseog; Bae, Jaechang; Demir, Meliksah; Achoui, Mustapha; Pang, Joyce S.; Jiang, Ding-Yu; Lamers, Sanne M.A.; Turan, Yücel; Lepshokova, Zarina Kh.; Panyusheva, Tatiana; Natalia, Amerkhanova; Asano, Ryosuke; Igarashi, Tasuku; Tsukamoto, Saori

    2016-01-01

    This study examined the relationship between 4 conceptions of happiness and life satisfaction in a sample of 2715 university students across 14 national groups. The 4 conceptions were self-transcendence, self-directed hedonism, conservation, and self-enhancement, which emerged from a principal compo

  19. The Concept of Distance: A Conceptual Problem in the Study of Literature.

    Science.gov (United States)

    Kasprisin, Lorraine

    1984-01-01

    Explanations critics have given of the concept of distance in the study of literature, i.e., distance and detachment from literary works necessary on the part of the reader, are discussed. The author then sketches her own ideas concerning a concept of distance that might be used in a future theory of literary response. (RM)

  20. Clusters of Concepts in Molecular Genetics: A Study of Swedish Upper Secondary Science Students' Understanding

    Science.gov (United States)

    Gericke, Niklas; Wahlberg, Sara

    2013-01-01

    To understand genetics, students need to be able to explain and draw connections between a large number of concepts. The purpose of the study reported herein was to explore the way upper secondary science students reason about concepts in molecular genetics in order to understand protein synthesis. Data were collected by group interviews. Concept…

  1. A Study of the Relationship Between Gesell's Developmental Age and Piaget's Concept of Conservation.

    Science.gov (United States)

    Civretta, Adeline E.

    A study was conducted to determine whether a significant correlation exists between developmental age and the concept of conservation. The hypothesis was that if developmental age and the concept of conservation are related, then stages of understanding conservation will increase as developmental age increases. Ss consisted of 30 primary children…

  2. Organic Chemistry Educators' Perspectives on Fundamental Concepts and Misconceptions: An Exploratory Study

    Science.gov (United States)

    Duis, Jennifer M.

    2011-01-01

    An exploratory study was conducted with 23 organic chemistry educators to discover what general chemistry concepts they typically review, the concepts they believe are fundamental to introductory organic chemistry, the topics students find most difficult in the subject, and the misconceptions they observe in undergraduate organic chemistry…

  3. Is 1 a Prime Number? Developing Teacher Knowledge through Concept Study

    Science.gov (United States)

    Davis, Brent

    2008-01-01

    "Concept study" is described in this article as a collaboration of teachers to investigate images, analogies, metaphors, exercises, and other experiences that are used to support students' understandings of concepts. The discussion is illustrated with the examples of multiplication and prime numbers. (Contains 3 figures.)

  4. Music Performance Teachers' Conceptions about Learning and Instruction: A Descriptive Study of Spanish Piano Teachers

    Science.gov (United States)

    Bautista, Alfredo; Echeverria, Ma Del Puy Perez; Pozo, J. Ignacio

    2010-01-01

    There has been little research into the conceptions music performance teachers have about learning and instruction, by either psychological or educational researchers. The main aim of this study was to describe the conceptions of 45 Spanish piano teachers from music conservatories, by analysing their differences according to the variable "Years of…

  5. Clusters of Concepts in Molecular Genetics: A Study of Swedish Upper Secondary Science Students' Understanding

    Science.gov (United States)

    Gericke, Niklas; Wahlberg, Sara

    2013-01-01

    To understand genetics, students need to be able to explain and draw connections between a large number of concepts. The purpose of the study reported herein was to explore the way upper secondary science students reason about concepts in molecular genetics in order to understand protein synthesis. Data were collected by group interviews. Concept…

  6. The Persistence of "Solid" and "Liquid" Naive Conceptions: A Reaction Time Study

    Science.gov (United States)

    Babai, Reuven; Amsterdamer, Anat

    2008-01-01

    The study explores whether the naive concepts of "solid" and "liquid" persist in adolescence. Accuracy of responses and reaction times where measured while 41 ninth graders classified different solids (rigid, non-rigid and powders) and different liquids (runny, dense) into solid or liquid. The results show that these naive conceptions affect…

  7. Organic Chemistry Educators' Perspectives on Fundamental Concepts and Misconceptions: An Exploratory Study

    Science.gov (United States)

    Duis, Jennifer M.

    2011-01-01

    An exploratory study was conducted with 23 organic chemistry educators to discover what general chemistry concepts they typically review, the concepts they believe are fundamental to introductory organic chemistry, the topics students find most difficult in the subject, and the misconceptions they observe in undergraduate organic chemistry…

  8. Study of the Relationship Between Nurse Self-Concept and Clinical Performance Among Nursing Students

    OpenAIRE

    Badiyepeymaie Jahromi; Kargar; Ramezanli

    2015-01-01

    Background Scholars believe that if nursing students appreciate the value of their services, their sense of professionalism will increase and performance will improve. Nevertheless, little is known about the relationship between nursing students’ professional self-concept and clinical performance. Objectives This study examines the relationship between nurse self-concept and clinical performance among nursing students. ...

  9. Music Performance Teachers' Conceptions about Learning and Instruction: A Descriptive Study of Spanish Piano Teachers

    Science.gov (United States)

    Bautista, Alfredo; Echeverria, Ma Del Puy Perez; Pozo, J. Ignacio

    2010-01-01

    There has been little research into the conceptions music performance teachers have about learning and instruction, by either psychological or educational researchers. The main aim of this study was to describe the conceptions of 45 Spanish piano teachers from music conservatories, by analysing their differences according to the variable…

  10. Conceptions and Misconceptions about Neuroscience in Preschool Teachers: A Study from Argentina

    Science.gov (United States)

    Hermida, M. J.; Segretin, M. S.; Soni García, A.; Lipina, S. J.

    2016-01-01

    Background: Teachers' conceptions and misconceptions about neuroscience are crucial in establishing a proper dialogue between neuroscience and education. In recent years, studies in different countries have examined primary and secondary school teachers' conceptions. However, although preschool education has proved its importance to later academic…

  11. Ethnocentric and Stereotypical Concepts in the Study of Islamic and World History.

    Science.gov (United States)

    Rahme, Joseph G.

    1999-01-01

    Evaluates the usage of five concepts in the study of Islamic and world history that serve to perpetuate the image of Islamic civilization as the Other: (1) Middle East; (2) East and West; (3) Judaic-Christian heritage; (4) Islamic fundamentalism; and (5) jihad. Argues for replacing these concepts. (CMK)

  12. Swedish Nursing Students' Perceptions of the Concept of Health: A Phenomenographic Study

    Science.gov (United States)

    Skär, Lisa; Söderberg, Siv

    2016-01-01

    Objectives: Health is a central and important concept in nursing and nursing education, and has been theorised about in both positive and negative terms. The purpose of this study was to explore Swedish nursing students' perceptions of the concept of health. Design: A phenomenographic research approach was used to understand how nursing students…

  13. An Exploratory Study of Taiwanese Mathematics Teachers' Conceptions of School Mathematics, School Statistics, and Their Differences

    Science.gov (United States)

    Yang, Kai-Lin

    2014-01-01

    This study used phenomenography, a qualitative method, to investigate Taiwanese mathematics teachers' conceptions of school mathematics, school statistics, and their differences. To collect data, we interviewed five mathematics teachers by open questions. They also responded to statements drawn on mathematical/statistical conceptions and…

  14. Music Performance Teachers' Conceptions about Learning and Instruction: A Descriptive Study of Spanish Piano Teachers

    Science.gov (United States)

    Bautista, Alfredo; Echeverria, Ma Del Puy Perez; Pozo, J. Ignacio

    2010-01-01

    There has been little research into the conceptions music performance teachers have about learning and instruction, by either psychological or educational researchers. The main aim of this study was to describe the conceptions of 45 Spanish piano teachers from music conservatories, by analysing their differences according to the variable…

  15. Comment on "Retrieval practice produces more learning than elaborative studying with concept mapping".

    Science.gov (United States)

    Mintzes, Joel J; Canas, Alberto; Coffey, John; Gorman, James; Gurley, Laine; Hoffman, Robert; McGuire, Saundra Y; Miller, Norma; Moon, Brian; Trifone, James; Wandersee, James H

    2011-10-28

    Karpicke and Blunt (Reports, 11 February 2011, p. 772) reported that retrieval practice produces greater gains in learning than elaborative studying with concept mapping and concluded that this strategy is a powerful way to promote meaningful learning of complex concepts commonly found in science education. We question their findings on methodological and epistemological grounds.

  16. A STUDY OF HOW A CHILD LEARNS CONCEPTS ABOUT CHARACTERISTICS OF LIQUID MATERIALS. FINAL REPORT.

    Science.gov (United States)

    ENGELMANN, SIEGFRIED; GALLAGHER, JAMES J.

    THE PURPOSE OF THE STUDY WAS TO EXPLORE THE PIAGET CONCEPT OF CONSERVATION WITH REGARD TO THE CHILD'S CONCEPT OF THE PROPERTY OF LIQUIDS. AN INVESTIGATOR-CONSTRUCTED CONSERVATION INVENTORY WAS GIVEN TO 45 KINDERGARTEN AND FIRST GRADE PUPILS SELECTED FROM THE PRAIRIE ELEMENTARY SCHOOLS, URBANA, ILLINOIS, TO PROVIDE AN INDEX OF THE CHILD'S…

  17. Recommended satellite imagery capabilities for disaster management

    Science.gov (United States)

    Richards, P. B.; Robinove, C. J.; Wiesnet, D. R.; Salomonson, V. V.; Maxwell, M. S.

    1982-01-01

    This study explores the role that satellite imaging systems might play in obtaining information needed in the management of natural and manmade disasters. Information requirements which might conceivably be met by satellite were identified for over twenty disasters. These requirements covered pre-disaster mitigation and preparedness activities, disaster response activities, and post-disaster recovery activities. The essential imaging satellite characteristics needed to meet most of the information requirements are 30 meter (or finer) spatial resolution, frequency of observations of one week or less, data delivery times of one day or less, and stereo, synoptic all-weather coverage of large areas in the visible, near infrared, thermal infrared and microwave bands. Of the current and planned satellite systems investigated for possible application to disaster management, Landsat-D and SPOT appear to have the greatest potential during disaster mitigation and preparedness activities, but all satellites studied have serious deficiencies during response and recovery activities. Several strawman concepts are presented for a satellite system optimized to support all disaster management activities.

  18. Reading for Integration, Identifying Complementary Threshold Concepts: The ACRL Framework in Conversation with Naming What We Know: Threshold Concepts of Writing Studies

    Directory of Open Access Journals (Sweden)

    Brittney Johnson

    2016-12-01

    Full Text Available In 2015, threshold concepts formed the foundation of two disciplinary documents: the ACRL Framework for Information Literacy (2015 and Naming What We Know: Threshold Concepts of Writing Studies (2015. While there is no consensus in the fields about the value of threshold concepts in teaching, reading the six Frames in the ACRL document alongside the threshold concepts of writing studies illuminates overlapping elements that may empower faculty in both fields to advocate collectively against skills-focused writing and research instruction through cross-disciplinary integrations. To facilitate cross-disciplinary conversations around the documents, the authors propose an order for reading the Frames, identify the associated writing concepts, and explain how the shared concepts reveal an internal complexity which may have implications for teaching the ACRL Framework.

  19. Validating a Modified Gagnean Concept-Acquisition Model: The Results of an Experimental Study Using Art-Related Content.

    Science.gov (United States)

    Stahl, Robert J.

    This paper describes a study to determine whether students can, with appropriate instructional materials, develop and apply a knowledge of art concepts. An opening section reviews research on concept acquisition. This study utilized a concept acquisition model developed in 1970 by R. Gagne. Gagne's model proposed that concepts are learned through…

  20. Tropical forest monitoring, combining satellite and social data, to inform management and livelihood implications: Case studies from Indonesian West Timor

    Science.gov (United States)

    Fisher, Rohan

    2012-06-01

    Deforestation in the world's tropics is an urgent international issue. One response has been the development of satellite based monitoring initiatives largely focused on the carbon rich forests of western Indonesia. In contrast this study focuses on one eastern Indonesian district, Kabupaten Kupang, which has some of the largest and least studied tracts of remaining forest in West Timor. A combination of remote sensing, GIS and social science methods were used to describe the state of forests in Kabupaten Kupang, how and why they are changing. Using satellite imagery, case studies and on-ground interviews, this study explores the proposition that transdisciplinary local social, cultural and biophysical knowledge is important for effectively using remotely sensed data as a tool to inform local management policies. When compared to some other parts of Indonesia, the rate and extent of deforestation in West Timor was found to be relatively small and a satellite based assessment alone could conclude that it is not a critical issue. However this study showed that when on-ground social data are coupled with (such) satellite-based data a more complex picture emerges, related to key livelihood issues. The causes of forest cover change were found to be multivariate and location specific, requiring management approaches tailored to local social issues. This study suggests that integrative research can maximise the utility of satellite data for understanding causation and thus informing management strategies. In addition, the satellite based assessment found that at the time of the study less than 4% of forested land was within national parks and nature reserves and less than a third of the protected catchment forest zone was forested. These data suggest considerable scope for upland re-forestation activities or the redrawing of protected forest boundaries.

  1. A study of temperature's spatial distribution in Neuquen River valley through satellite imaging

    Directory of Open Access Journals (Sweden)

    Marisa Gloria Cogliati

    2010-01-01

    Full Text Available This paper looks into the spatial distribution of brightness and surface temperature through the use of LAND SAT7 ETM+ and NO AA-AVHRR satellite imagery in the cultivated valley of the Neuquén river. Studying the spatial distribution of temperatures in an area with a somewhat complex terrain requires the use of a great density of meteorological measurements. It is often impossible to obtain the right density of the argometeorological network due to the high installation and maintenance costs. Remote sensors provide a large flow of information in various resolutions, at considerably lower costs. Determining the valley's warm and cold zones would allow for more efficient irrigation and frost-protection methods, and it would provide tools to improve the area's productive planning.

  2. A Deep Study of the Dwarf Satellites Andromeda XXVIII & Andromeda XXIX

    CERN Document Server

    Slater, Colin T; Martin, Nicolas F; Tollerud, Erik J; Ho, Nhung

    2015-01-01

    We present the results of a deep study of the isolated dwarf galaxies Andromeda XXVIII and Andromeda XXIX with Gemini/GMOS and Keck/DEIMOS. Both galaxies are shown to host old, metal-poor stellar populations with no detectable recent star formation, conclusively identifying both of them as dwarf spheroidal galaxies (dSphs). And XXVIII exhibits a complex horizontal branch morphology, which is suggestive of metallicity enrichment and thus an extended period of star formation in the past. Decomposing the horizontal branch into blue (metal poor, assumed to be older) and red (relatively more metal rich, assumed to be younger) populations shows that the metal rich are also more spatially concentrated in the center of the galaxy. We use spectroscopic measurements of the Calcium triplet, combined with the improved precision of the Gemini photometry, to measure the metallicity of the galaxies, confirming the metallicity spread and showing that they both lie on the luminosity-metallicity relation for dwarf satellites. ...

  3. Rain induced attenuation studies for V-band satellite communication in tropical region

    Science.gov (United States)

    Badron, Khairayu; Ismail, Ahmad Fadzil; Din, Jafri; Tharek, Abd. Rahman

    2011-04-01

    Satellite communications operating at 10 GHz and above in the tropics suffer severe signal degradation due to rain. Attenuation due to rain at 38 GHz had been measured for a period of 20 months in Malaysia. Analyses carried out include seasonal variations, diurnal effects and the annual cumulative distributions. Obtained results were compared with several established prediction models including the ITU-R. The rain fade characteristics were also investigated in determining the levels of signal loss and fading. In addition, the studies highlight several potential fade mitigation techniques that can be embarked. These fundamental aprehensions are very critical for future earth space communication link design and can be exploited as preliminary groundwork plan for the researchers as well as engineers.

  4. Satellite Altimetry And Radiometry for Inland Hydrology, Coastal Sea-Level And Environmental Studies

    Science.gov (United States)

    Tseng, Kuo-Hsin

    In this study, we demonstrate three environmental-related applications employing altimetry and remote sensing satellites, and exemplify the prospective usage underlying the current progressivity in mechanical and data analyzing technologies. Our discussion starts from the improved waveform retracking techniques in need for altimetry measurements over coastal and inland water regions. We developed two novel auxiliary procedures, namely the Subwaveform Filtering (SF) method and the Track Offset Correction (TOC), for waveform retracking algorithms to operationally detect altimetry waveform anomalies and further reduce possible errors in determination of the track offset. After that, we present two demonstrative studies related to the ionospheric and tropospheric compositions, respectively, as their variations are the important error sources for satellite electromagnetic signals. We firstly compare the total electron content (TEC) measured by multiple altimetry and GNSS sensors. We conclude that the ionosphere delay measured by Jason-2 is about 6-10 mm shorter than the GPS models. On the other hand, we use several atmospheric variables to study the climate change over high elevation areas. Five types of satellite data and reanalysis models were used to study climate change indicators. We conclude that the spatial distribution of temperature trend among data products is quite different, which is probably due to the choice of various time spans. Following discussions about the measuring techniques and relative bias between data products, we applied our improved altimetry techniques to three environmental science applications with helps of remote sensing imagery. We first manifest the detectability of hydrological events by satellite altimetry and radiometry. The characterization of one-dimensional (along-track) water boundary using former Backscattering Coefficient (BC) method is assisted by the two-dimensional (horizontal) estimate of water extent using the Moderate

  5. Techniques for Conducting Effective Concept Design and Design-to-Cost Trade Studies

    Science.gov (United States)

    Di Pietro, David A.

    2015-01-01

    Concept design plays a central role in project success as its product effectively locks the majority of system life cycle cost. Such extraordinary leverage presents a business case for conducting concept design in a credible fashion, particularly for first-of-a-kind systems that advance the state of the art and that have high design uncertainty. A key challenge, however, is to know when credible design convergence has been achieved in such systems. Using a space system example, this paper characterizes the level of convergence needed for concept design in the context of technical and programmatic resource margins available in preliminary design and highlights the importance of design and cost evaluation learning curves in determining credible convergence. It also provides techniques for selecting trade study cases that promote objective concept evaluation, help reveal unknowns, and expedite convergence within the trade space and conveys general practices for conducting effective concept design-to-cost studies.

  6. Nanosar-case study of synthetic aperture radar for nano-satellites

    NARCIS (Netherlands)

    Engelen, S.; Oever, M. van den; Mahapatra, P.; Sundaramoorthy, P.; Gill, E.; Meijer, R.J.; Verhoeven, C.

    2012-01-01

    Nano-satellites have a cost advantage due to their low mass and usage of commercial-off-the-shelf technologies. However, the low mass also restricts the functionality of a nano-satellite's payload. Typically, this would imply instruments with very low to low resolution and accuracy, essentially

  7. Nanosar-case study of synthetic aperture radar for nano-satellites

    NARCIS (Netherlands)

    Engelen, S.; Oever, M. van den; Mahapatra, P.; Sundaramoorthy, P.; Gill, E.; Meijer, R.J.; Verhoeven, C.

    2012-01-01

    Nano-satellites have a cost advantage due to their low mass and usage of commercial-off-the-shelf technologies. However, the low mass also restricts the functionality of a nano-satellite's payload. Typically, this would imply instruments with very low to low resolution and accuracy, essentially ruli

  8. 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.

  9. A long-term satellite study of aerosol effects on convective clouds in Nordic background air

    Directory of Open Access Journals (Sweden)

    M. K. Sporre

    2013-05-01

    Full Text Available Aerosol-cloud interactions constitute a~major uncertainty in future climate predictions. This study combines 10 yr of ground-based aerosol particle measurements from 2 Nordic background stations (Vavihill and Hyytiälä with MODIS (Moderate Resolution Imaging Spectroradiometer satellite data of convective clouds. The merged data are used to examine the indirect aerosol effects on convective clouds over the Nordic countries. From the satellite scenes, vertical profiles of cloud droplet effective radius (re are created by plotting re against cloud top temperature. The profiles have been divided according to aerosol loading but also modeled meteorological parameters from the ECMWF (European Centre for Medium-Range Forecasts. Furthermore, weather radar data from the BALTEX (Baltic Sea Experiment and ground based precipitation measurements from several ground-based meteorological measurement stations have been investigated to determine whether aerosols affect precipitation intensity and amount. Higher aerosol number concentrations result in smaller re throughout the entire profiles at both stations. Profiles associated with no or little precipitation have smaller droplets than those associated with more precipitation. Furthermore, an increase in aerosol loadings results in a suppression of precipitation rates, when the vertical extent of the clouds has been taken into account. Clouds with greater vertical extent have the highest precipitation rates and are most sensitive to aerosol perturbations. Nevertheless, meteorological parameters such as the vertical extent of the clouds, the atmospheric instability and the relative humidity in the lower atmosphere affect the amount of precipitation that reaches the ground more than the aerosols do. The combination of these ground-based and remote sensing datasets provides a unique long-term study of the effects of aerosols on convective clouds over the Nordic countries.

  10. A study of L-dependent Pc3 pulsations observed by low Earth orbiting CHAMP satellite

    Directory of Open Access Journals (Sweden)

    D. C. Ndiitwani

    2010-02-01

    Full Text Available Field line resonances (FLR driven by compressional waves are an important mechanism for the generation of ULF geomagnetic pulsations observed at all latitudes during local daytime. References to observations of toroidal standing Alfvén mode oscillations with clearly L-dependent frequencies from spacecraft in the outer magnetosphere for L>3 are limited in the literature. Such observations in the inner magnetosphere for L<3 have not yet been reported in the literature. This study offers two interesting case studies of observations of ULF waves by the low Earth orbiting CHAMP satellite. The magnetic field measurements from CHAMP, which are of unprecedented accuracy and resolution, are compared to Hermanus magnetometer data for times when CHAMP crosses the ground station L-shell, namely for 13 February 2002 and 18 February 2003. The data were analysed for Pc3 pulsation activity using the Maximum Entropy Spectral Analysis (MESA method to visualise FLRs in the vector magnetometer data. For the first time observations of Pc3 toroidal oscillations with clearly L-dependent frequencies for lower L-shell values (L<3 observed by an LEO satellite are reported. These observations show FLR frequencies increasing as a function of decreasing latitude down to L=1.6 and then decreasing as a result of the larger plasma density of the upper ionosphere. The L-dependent frequency oscillations were observed in the presence of a broadband compressional wave spectrum. Our observations thus confirm the well-known magnetohydrodynamic (MHD wave theoretical prediction of a compressional wave being the driver of the field line resonance.

  11. Cadastral Resurvey using High Resolution Satellite Ortho Image - challenges: A case study in Odisha, India

    Science.gov (United States)

    Parida, P. K.; Sanabada, M. K.; Tripathi, S.

    2014-11-01

    Advancements in satellite sensor technology enabling capturing of geometrically accurate images of earth's surface coupled with DGPS/ETS and GIS technology holds the capability of large scale mapping of land resources at cadastral level. High Resolution Satellite Images depict field bunds distinctly. Thus plot parcels are to be delineated from cloud free ortho-images and obscured/difficult areas are to be surveyed using DGPS and ETS. The vector datasets thus derived through RS/DGPS/ETS survey are to be integrated in GIS environment to generate the base cadastral vector datasets for further settlement/title confirmation activities. The objective of this paper is to illustrate the efficacy of a hybrid methodology employed in Pitambarpur Sasana village under Digapahandi Tahasil of Ganjam district, as a pilot project, particularly in Odisha scenario where the land parcel size is very small. One of the significant observations of the study is matching of Cadastral map area i.e. 315.454 Acres, the image map area i.e. 314.887 Acres and RoR area i.e. 313.815 Acre. It was revealed that 79 % of plots derived by high-tech survey method show acceptable level of accuracy despite the fact that the mode of area measurement by ground and automated method has significant variability. The variations are more in case of Government lands, Temple/Trust lands, Common Property Resources and plots near to river/nalas etc. The study indicates that the adopted technology can be extended to other districts and cadastral resurvey and updating work can be done for larger areas of the country using this methodology.

  12. 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.

  13. Severe thunderstorm activity over Bihar on 21st April, 2015: a simulation study by satellite based Nowcasting technique

    Science.gov (United States)

    Goyal, Suman; Kumar, Ashish; Sangar, Ghansham; Mohapatra, M.

    2016-05-01

    Satellite based Nowcasting technique is customized version of Forecast and Tracking the Evolution of Cloud Clusters (ForTraCC), it uses the extrapolation technique that allows for the tracking of Mesoscale convective systems (MCS) radiative and morphological properties and forecasts the evolution of these properties (based on cloud-top brightness temperature and area of the cloud cluster) up to 360 minutes, using infrared satellite imagery. The Thermal Infrared (TIR) channel of the weather satellite has been broadly used to study the behaviour of the cloud systems associated with deep convection. The main advantage of this approach is that for most of the globe the best statistics can only be obtained from satellite observations. Such a satellite survey would provide the statistics of MCSs covering the range of meteorological conditions needed to generalize the result and on the other hand only satellite observations can cover the very large range of space and time scale. The algorithm script is taken from Brazilian Scientist Dr. Danial Vila and implemented it into the Indian environment and made compatible with INSAT-3D hdf5 data format. For Indian region it utilizes the INSAT-3D satellite data of TIR1 (10.8 μm) channel and creates nowcast. The output is made compatible with GUI based software MIAS by generating the output in hdf5 format for better understanding and analysis of forecast. The main features of this algorithm are detection of Cloud Cluster based on Cloud Top Brightness Temperature (CTBT) and area i.e. ≤235 ºK and ≥2400 km2 respectively. The tracking technique based on MCS overlapping areas in successive images. The script has been automized in Auxiliary Data Processing System (ADPS) and generating the forecast file in every half an hour and convert the output file in geotiff format. The geotiff file is easily converted into KMZ file format using ArcGIS software to overlay it on google map and hosted on the web server.

  14. 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.

  15. 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.

  16. Study of the Relationship Between Nurse Self-Concept and Clinical Performance Among Nursing Students

    Directory of Open Access Journals (Sweden)

    Badiyepeymaie Jahromi

    2015-09-01

    Full Text Available Background Scholars believe that if nursing students appreciate the value of their services, their sense of professionalism will increase and performance will improve. Nevertheless, little is known about the relationship between nursing students’ professional self-concept and clinical performance. Objectives This study examines the relationship between nurse self-concept and clinical performance among nursing students. Patients and Methods This cross-sectional analytical study employed the census method. The sample comprised 86 senior and junior nursing students at Jahrom university of medical sciences. Nurse self-concept and clinical performance were measured by using the nurses’ self-concept questionnaire (NSCQ, and the 6-dimension scale of nurse performance (6-DSNP, respectively. Results The mean and standard deviation of nurse self-concept and clinical performance scores were 5.46 ± 1.11 and 2.94 ± 1.45, respectively. Nurse self-concept was related to clinical performance (r = 0.24, P = 0.02. Total NSCQ scores were significantly related to four of the 6-DSNP dimensions: planning and evaluation, interpersonal relations and communication, critical care, and leadership. Conclusions Attempts should be made to enhance students’ nurse self-concept during their education. Counseling, improving public respect for nurses, and implementing measures to enhance students’ professional self-concept are essential for improving their performance.

  17. 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...

  18. 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

  19. Students' conceptions of the medical profession: an interview study.

    OpenAIRE

    Nieuwhof, M.G.H.; Rademakers, J.J.D.J.M.; Kuyvenhoven, M M; Soethout, M.B.M.; ten Cate, Th.J.

    2005-01-01

    Students' beliefs and attitudes towards the medical profession have been studied in relation to career choices, but most research has been restricted to either predetermined aspects or to a limited number of specialties. This study aimed at getting unprompted insight in the students' perceptions of their future profession in dimensions that may be determinants of study success and career choice. Undergraduate and graduated medical students were interviewed and asked to characterize the medica...

  20. A Case Study Examining Egypt, Nigeria, and Venezuela and their Flaring Behavior Utilizing VIIRS Satellite Data

    Science.gov (United States)

    Englander, J. G.; Austin, A. T.; Brandt, A. R.

    2016-12-01

    The need to quantify flaring by oil and gas fields is receiving more scrutiny, as there has been scientific and regulatory interest in quantifying the greenhouse gas (GHG) impact of oil and gas production. The National Oceanic and Atmospheric Administration (NOAA) has developed a method to track flaring activity using a Visible Infrared Imaging Radiometer Suite (VIIRS) satellite.[1] This reports data on the average size, power, and light intensity of each flare. However, outside of some small studies, the flaring intensity has generally been estimated at the country level.[2]While informative, country-level assessments cannot provide guidance about the sustainability of particular crude streams or products produced. In this work we generate detailed oil-field-level flaring intensities for a number of global oilfield operations. We do this by merging the VIIRS dataset with global oilfield atlases and other spatial data sources. Joining these datasets together with production data allows us to provide better estimates for the GHG intensity of flaring at the field level for these countries.[3]First, we compute flaring intensities at the field level for 75 global oil fields representing approximately 25% of global production. In addition, we examine in detail three oil producing countries known to have high rates of flaring: Egypt, Nigeria, and Venezuela. For these countries we compute the flaring rate for all fields in the country and explore within-and between-country variation. The countries' fields will be analyzed to determine the correlation of flare activity to a certain field type, crude type, region, or production method. [1] Cao, C. "Visible Infrared Imaging Radiometer Suite (VIIRS)." NOAA NPP VIIRS. NOAA, 2013. Web. 30 July 2016. [2] Elvidge, C. D. et al., "A Fifteen Year Record of Global Natural Gas Flaring Derived from Satellite Data," Energies, vol. 2, no. 3, pp. 595-622, Aug. 2009. [3] World Energy Atlas. 6th ed. London: Petroleum Economist, 2011. Print.

  1. The study of Be stars with the CoRoT satellite

    Science.gov (United States)

    Diago, P. D.; Gutierrez-Soto, J.; Fabregat, J.; Suso, J.; COROT Be Team

    2011-11-01

    The CoRoT space mission, launched in December 2006, is a spacecraft devoted to the study of the stellar interiors and the exo-planet search. Concerning the seismology of the Be stars, the presence of pulsations in late-type Be stars is still a matter of controversy. It constitutes an important issue to establish the relationship between non-radial pulsations and the mass-loss mechanism in Be stars. In this field, the CoRoT satellite is providing data with an unprecedent quality and precision that is confirming non-radial pulsations in Be stars. The CoRoT Be Team is an international collaboration composed by members from France, Spain, Brazil and Belgium and is in charge of the exploitation and analysis of the Be stars data. In this work we present the highlighted results of the observed Be stars by CoRoT and the future prospects of the CoRoT Be Team. These results include the detection of the Be star HD 49 330 during an outburst phase and the measurement of the change in the oscillation spectrum during this rare event. These observations gave insight into the nature of the explosion. It will help to solve a question that has been pending for years: are oscillations the cause of the outbursts? Moreover, for the first time, the CoRoT satellite has detected simultaneously the rotational and the pulsational frequencies for the Be star HD 50 209, which constitutes a proof of the presence of pulsations in the Be stars. %J Highlights of Spanish Astrophysics VI, Proceedings of the IX Scientific Meeting of the Spanish Astronomical Society (SEA), held in Madrid, September 13 - 17, 2010, Eds.: M. R. Zapatero Osorio, J. Gorgas, J. Maiz Apellaniz, J. R. Pardo, and A. Gil de Paz., p. 531-531

  2. Study on the detection of red-tide outbreaks using big satellite database

    Science.gov (United States)

    Son, Young Baek; Eun, Yoon Joo; Park, Kyongseok; Lee, Sanghwan; Lee, Ryong; Kim, Sang-Hyun; Yoo, Sinjae

    2014-11-01

    Satellite remote sensing has been successfully employed to monitor and detect the increasing incidence of harmful algal blooms (HABs) under various water conditions. In this study, to establish a comprehensive monitoring system of HAB outbreaks (particularly Cochlodinium polykrikoides blooms) in the southern coast of Korea (SCK), we tested the several proposed red-tide detection methods using SeaWiFS and MODIS ocean color data. Temporal and spatial information of red tide events from 2002 to 2013 were obtained from the National Fisheries Research and Development of Korea (NFRDI), which were matched with synchronously obtained satellite-derived ocean color data. The spectral characteristics of C. polykrikoides red tides were that increased phytoplankton absorption at 443 nm and pigment backscattering 555 nm resulted in a steeper slope between 488 and 555 nm with a hinge point at 488 (or 490) nm. On the other hand, non-red tide water, typically were presented by broader radiance spectra between the blue and green bands were associated with reduced pigment absorption and backscattering. The analysis of ocean color imageries that captured C. polykrikoides red tide blooms showed discolored waters with enhanced pigment concentrations, high chlorophyll, fluorescence, absorption at 443 nm. However, most red tide detection algorithms found a large number of false positive but only a small number of true positive areas. These proposed algorithms are not useful to distinguish true red tide water from complex non-red tide water. Our proposed method substantially reduces the false signal rate (false positive) from strong absorption at short wavelengths and provide a more reliable and robust detection of C. polykrikoides blooms in the SCK from the space.

  3. Students' conceptions of the medical profession: an interview study.

    NARCIS (Netherlands)

    Nieuwhof, M.G.H.; Rademakers, J.J.D.J.M.; Kuyvenhoven, M.M.; Soethout, M.B.M.; Cate, Th.J. ten

    2005-01-01

    Students' beliefs and attitudes towards the medical profession have been studied in relation to career choices, but most research has been restricted to either predetermined aspects or to a limited number of specialties. This study aimed at getting unprompted insight in the students' perceptions of

  4. Revisiting Style, a Key Concept in Literary Studies

    NARCIS (Netherlands)

    Herrmann, J. Berenike; van Dalen-Oskam, K.H.; Schöch, Christof

    2015-01-01

    Language and literary studies have studied style for centuries, and even since the advent of ›stylistics‹ as a discipline at the beginning of the twentieth century, definitions of ›style‹ have varied heavily across time, space and fields. Today, with increasingly large collections of literary texts

  5. Students' conceptions of the medical profession: an interview study.

    NARCIS (Netherlands)

    Nieuwhof, M.G.H.; Rademakers, J.J.D.J.M.; Kuyvenhoven, M.M.; Soethout, M.B.M.; Cate, Th.J. ten

    2005-01-01

    Students' beliefs and attitudes towards the medical profession have been studied in relation to career choices, but most research has been restricted to either predetermined aspects or to a limited number of specialties. This study aimed at getting unprompted insight in the students' perceptions of

  6. Revisiting Style, a Key Concept in Literary Studies

    NARCIS (Netherlands)

    Herrmann, J. Berenike; van Dalen-Oskam, K.H.; Schöch, Christof

    2015-01-01

    Language and literary studies have studied style for centuries, and even since the advent of ›stylistics‹ as a discipline at the beginning of the twentieth century, definitions of ›style‹ have varied heavily across time, space and fields. Today, with increasingly large collections of literary texts

  7. Ecocultural effects on self-concept. A study with young indigenous people from different sociodemographic contexts.

    Science.gov (United States)

    Esteban-Guitart, Moisès; Borke, Jörn; Monreal-Bosch, Pilar

    2015-08-01

    This study explores self-concept among indigenous young people from different ecocultural niches in Chiapas (Mexico) through a particular self-concept task. Previous theory and research has described 3 cultural models linked with specific sociodemographic settings that foster particular psychologies. Our aim was to compare the results of the self-concept test among indigenous groups from different sociodemographic settings in order to observed possible differences. We predicted that individuals from rural communities with little formal education (hypothesised to be Interdependent) would have self-concepts with more social and less personal components than would those with an urban, highly educated (hypothesised to be Independent), and we expected a third group of highly educated young people living in an urban context but with a rural background (hypothesised to be autonomous-related group) to value social and personal components equally. The results supported this hypothesis. Based on ecocultural theory, it is suggested that sociodemographic contexts affect the self-concept.

  8. The determinations of remote sensing satellite data delivery service quality: A positivistic case study in Chinese context

    Science.gov (United States)

    Jin, Jiahua; Yan, Xiangbin; Tan, Qiaoqiao; Li, Yijun

    2014-03-01

    With the development of remote sensing technology, remote-sensing satellite has been widely used in many aspects of national construction. Big data with different standards and massive users with different needs, make the satellite data delivery service to be a complex giant system. How to deliver remote-sensing satellite data efficiently and effectively is a big challenge. Based on customer service theory, this paper proposes a hierarchy conceptual model for examining the determinations of remote-sensing satellite data delivery service quality in the Chinese context. Three main dimensions: service expectation, service perception and service environment, and 8 sub-dimensions are included in the model. Large amount of first-hand data on the remote-sensing satellite data delivery service have been obtained through field research, semi-structured questionnaire and focused interview. A positivist case study is conducted to validate and develop the proposed model, as well as to investigate the service status and related influence mechanisms. Findings from the analysis demonstrate the explanatory validity of the model, and provide potentially helpful insights for future practice.

  9. A qualitative study on using concept maps in problem-based learning.

    Science.gov (United States)

    Chan, Zenobia C Y

    2017-05-01

    The visual arts, including concept maps, have been shown to be effective tools for facilitating student learning. However, the use of concept maps in nursing education has been under-explored. The aim of this study was to explore how students develop concept maps and what these concept maps consist of, and their views on the use of concept maps as a learning activity in a PBL class. A qualitative approach consisting of an analysis of the contents of the concept maps and interviews with students. The study was conducted in a school of nursing in a university in Hong Kong. A total of 38 students who attended the morning session (20 students) and afternoon session (18 students) respectively of a nursing problem-based learning class. The students in both the morning and afternoon classes were allocated into four groups (4-5 students per group). Each group was asked to draw two concept maps based on a given scenario, and then to participate in a follow-up interview. Two raters individually assessed the concept maps, and then discussed their views with each other. Among the concept maps that were drawn, four were selected. Their four core features of those maps were: a) the integration of informative and artistic elements; b) the delivery of sensational messages; c) the use of images rather than words; and d) three-dimensional and movable. Both raters were concerned about how informative the presentation was, the composition of the elements, and the ease of comprehension, and appreciated the three-dimensional presentation and effective use of images. From the results of the interview, the pros and cons of using concept maps were discerned. This study demonstrated how concept maps could be implemented in a PBL class to boost the students' creativity and to motivate them to learn. This study suggests the use of concept maps as an initiative to motivate student to learn, participate actively, and nurture their creativity. To conclude, this study explored an alternative way

  10. 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

  11. The behaviour of satellite cells in response to exercise: what have we learned from human studies?

    DEFF Research Database (Denmark)

    Kadi, Fawzi; Olsen, Steen Schytte

    2005-01-01

    Understanding the complex role played by satellite cells in the adaptive response to exercise in human skeletal muscle has just begun. The development of reliable markers for the identification of satellite cell status (quiescence/activation/proliferation) is an important step towards the underst......Understanding the complex role played by satellite cells in the adaptive response to exercise in human skeletal muscle has just begun. The development of reliable markers for the identification of satellite cell status (quiescence/activation/proliferation) is an important step towards...... the understanding of satellite cell behaviour in exercised human muscles. It is hypothesised currently that exercise in humans can induce (1) the activation of satellite cells without proliferation, (2) proliferation and withdrawal from differentiation, (3) proliferation and differentiation to provide myonuclei...... and (4) proliferation and differentiation to generate new muscle fibres or to repair segmental fibre injuries. In humans, the satellite cell pool can increase as early as 4 days following a single bout of exercise and is maintained at higher level following several weeks of training. Cessation...

  12. 492 Study Habit, Self-Concept and Science Achievement of Public ...

    African Journals Online (AJOL)

    Nekky Umera

    Key Words: Study habit, self-concept, science achievement, public and private schools ... teacher commitment and sometimes better facilities than government schools. ... skills like note-taking, time management, organizing for a test, recording.

  13. 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...

  14. Study of the turbulence in the central plasma sheet using the CLUSTER satellite data

    Science.gov (United States)

    Stepanova, M.; Arancibia Riveros, K.; Bosqued, J.; Antonova, E.

    2008-05-01

    Recent studies are shown that the turbulent processes in the space plasmas are very important. It includes the behavior of the plasma sheet plasma during geomagnetic substorms and storms. Study of the plasma turbulence in the central plasma sheet was made using the CLUSTER satellite mission data. For this studies we used the Cluster Ion Spectrometry experiment (CIS), and fluxgate magnetometer (FGM) data for studying fluctuations of the plasma bulk velocity and geomagnetic field fluctuations for different levels of geomagnetic activity and different locations inside the plasma sheet. Case studies for the orbits during quiet geomagnetic conditions, different phases of geomagnetic substroms and storms showed that the properties of plasma turbulence inside the sheet differ significantly for all afore mentioned cases. Variations in the probability distribution functions, flatness factors, local intermittency measure parameters, and eddy diffusion coefficients indicate that the turbulence increases significantly during substorm growth and expansion phases and decreases slowly to the initial level during the recovery phase. It became even stronger during the storm main phase.

  15. Forest fires detection in Indonesia using satellite Himawari-8 (case study: Sumatera and Kalimantan on august-october 2015)

    Science.gov (United States)

    Fatkhuroyan; Wati, Trinah; Panjaitan, Andersen

    2017-01-01

    Forest fires in Indonesia are serious problem affecting widely in material losses, health and environment. Himawari-8 as one of meteorological satellites with high resolution 0,5 km x 0,5 km can be used for forest fire monitoring and detection. Combination between 3, 4 and 6 channels using Sataid (Satellite Animation and Interactive Diagnosis) software will visualize forest fire in the study site. Monitoring which used Himawari-8 data on August, September and October 2015 can detect the distribution of smoke and the extents of forest fire in Sumatera and Kalimantan. The result showed the extent of forest fire can be identified for anticipation in the next step.

  16. Study to forecast and determine characteristics of world satellite communications market

    Science.gov (United States)

    Filep, R. T.; Schnapf, A.; Fordyce, S. W.

    1983-01-01

    The world commercial communications satellite market during the spring and summer of 1983 was examined and characteristics and forecasts of the market extending to the year 2000 were developed. Past, present and planned satellites were documented in relation to frequencies, procurement and launch dates, costs, transponders, and prime contractor. Characteristics of the market are outlined for the periods 1965 - 1985, 1986 - 1989, and 1990 - 2000. Market share forecasts, discussions of potential competitors in various world markets, and profiles of major communication satellite manufacturing and user countries are documented.

  17. Concept Studies of Micro-Pump for Chemical Concentration in Handheld Micro Sensors

    Science.gov (United States)

    2007-11-02

    This report summarizes the preliminary results of a short-term innovative research project on the concept study of micro pumps for chemical...main objective of the work is to study the feasibility of certain micro pumping concepts and their potential integration with the sensing material and... micro pumps is demonstrated, although the quantitative assessment of the pumping system is still elusive, partly because of lack of specifications. The

  18. Concept study and validation of Antartic telescope tower

    NARCIS (Netherlands)

    Lanford, E.; Swain, M.; Meyers, C.; Muramatsu, T.; Nielson, G.; Olson, V.; Ronsse, S.; Vinding Nyden, E.; Hammerschlag, R.H.; Little, P.

    2006-01-01

    Studies by Mark Swain and a colleague at the Max Planck Institut für Astronomie, coupled with results from past and ongoing projects at Harvey Mudd College, strongly suggest that it may be possible to achieve imaging performance comparable to the Hubble Space Telescope at relatively low cost using a

  19. Adolescents’ Interpretation of the Concept of Wellness: A Qualitative Study

    OpenAIRE

    Ezihe Loretta Ahanonu; Karien Jooste

    2016-01-01

    Introduction: This study sought to explore and describe the interpretation which adolescents ascribe to the term wellness at a selected high school in the Western Cape Province of South Africa. Methods: A qualitative research design was utilized. Nine focus-group discussions were conducted among 58 adolescents. Sample was selected purposefully and collected data was analyzed using open coding. Results: Findings reflected adolescents’ interpretation...

  20. Anti-aging proof of concept study: results and summary.

    Science.gov (United States)

    Bruce, Suzanne; Karnik, Jwala; Dryer, Laurence; Burkholder, David

    2014-09-01

    The etiology of aging human skin includes intrinsic physiologic changes greatly accelerated by photoaging, predominantly through exposure to UV light. Consumer interest and demand for anti-aging skin care products is extremely high especially in light of aging populations. Prenatal (fetal) tissue has been shown to possess healing characteristics and regenerative effects. A proprietary tissue engineering technology has been developed to produce a soluble human extracellular matrix material with growth factors and proteins. Neonatal cells are cultured on microbeads under conditions of low oxygen tension. This human cell-conditioned media (hCCM) contains a variety of growth factors and cytokines similar to those found in fetal cells and has been incorporated into a topical preparation for use in facial wound healing (after laser resurfacing procedures) and improving the appearance of aging skin. The objective of this study was to observe the effects of an MRCx™-containing topical skincare regimen on subjects with demonstrated aging skin damage (photodamage) when used consistently over a 3 month time period. Female subjects age 35-65 with Fitzpatrick Skin Type I-IV and mild to moderate amounts of photodamage, fine lines, and wrinkles used Regenica® Replenishing Crème and Regenica® Renew SPF 15 for 3 months. At each visit, photos were taken of subjects while investigators completed skin grading assessments and subjects completed self-assessments. Investigator assessments included evaluation of tactile roughness, visual texture, wrinkles, blotchiness, skin tone evenness, radiance, and translucence on a 5-point scale. Subjects' self-assessments included assessment of fine lines and wrinkles, firmness, evenness of skin tone, brightness, resilience, clarity, and radiance. Changes from baseline were evaluated for each parameter and P values for changes from baseline to each study visit for investigator's assessments and to end-of-study for self-assessments were

  1. Students' conceptions of the medical profession; an interview study.

    Science.gov (United States)

    Nieuwhof, M G H; Rademakers, J J D J M; Kuyvenhoven, M M; Soethout, M B M; ten Cate, Th J

    2005-12-01

    Students' beliefs and attitudes towards the medical profession have been studied in relation to career choices, but most research has been restricted to either predetermined aspects or to a limited number of specialties. This study aimed at getting unprompted insight in the students' perceptions of their future profession in dimensions that may be determinants of study success and career choice. Undergraduate and graduated medical students were interviewed and asked to characterize the medical profession in general and four contrasting specialties in particular. Grounded Theory methodology was used to analyse the data. Participants were medical students at the start of their training (n = 16), during clerkships (n = 10) and after graduation (n = 37). Beginning students perceive the medical profession in limited dimensions: the activities of a physician, their relationship to patients and the physician's knowledge, skills and personality. They do not see many differences between specialties, in contrast with students with clinical experience and graduate students. Undergraduate students' perception is focussed more on social aspects of the profession compared to graduates.

  2. Advanced vehicle concepts systems and design analysis studies

    Science.gov (United States)

    Waters, Mark H.; Huynh, Loc C.

    1994-01-01

    The work conducted by the ELORET Institute under this Cooperative Agreement includes the modeling of hypersonic propulsion systems and the evaluation of hypersonic vehicles in general and most recently hypersonic waverider vehicles. This work in hypersonics was applied to the design of a two-stage to orbit launch vehicle which was included in the NASA Access to Space Project. Additional research regarded the Oblique All-Wing (OAW) Project at NASA ARC and included detailed configuration studies of OAW transport aircraft. Finally, work on the modeling of subsonic and supersonic turbofan engines was conducted under this research program.

  3. WWC Quick Review of "Retrieval Practice Produces More Learning than Elaborative Studying with Concept Mapping"

    Science.gov (United States)

    What Works Clearinghouse, 2011

    2011-01-01

    The study examined whether using the retrieval-practice studying technique--in which students alternate between reading a passage and writing memorable information from that passage--improved student learning of a science passage more than the study-once, repeated-study, or concept-mapping techniques. The study found that students using the…

  4. Concepts and Methodologies to Study Protein SUMOylation: An Overview.

    Science.gov (United States)

    Matunis, Michael J; Rodriguez, Manuel S

    2016-01-01

    Protein modification by the small ubiquitin-related modifier (SUMO) was simultaneously discovered by several groups at the middle of the 1990s. Although distinct names were proposed including Sentrin, GMP1, PIC1, or SMT3, SUMO became the most popular. Early studies on the functions of SUMOylation focused on activities in the nucleus, including transcription activation, chromatin structure, and DNA repair. However, it is now recognized that SUMOylation affects a large diversity of cellular processes both in the nucleus and the cytoplasm and functions of SUMOylation appear to have undefined limits. SUMO-conjugating enzymes and specific proteases actively regulate the modification status of target proteins. The recent discoveries of ubiquitin-SUMO hybrid chains, multiple SUMO-interacting motifs, and macromolecular complexes regulated by SUMOylation underscore the high complexity of this dynamic reversible system. New conceptual frameworks suggested by these findings have motivated the development of new methodologies to study pre- and post-SUMOylation events in vitro and in vivo, using distinct model organisms. Here we summarize some of the new developments and methodologies in the field, particularly those that will be further elaborated on in the chapters integrating this book.

  5. Satellite and ship studies of phytoplankton along the west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Goes, J.I.; Gomes, H.; Kumar, A; Gouveia, A; Devassy, V.P.; Parulekar, A; Rao, L.V.G.

    AidEd. by a sequence of chlorophyll images from the Coastal Zone Color Scanner on board the Nimbus-7 satellite and extensive shipboard observations, a descriptive analysis of the factors influencing the distribution and production of phytoplankton...

  6. Exploration of satellite-derived data products for atmospheric turbulence studies

    CSIR Research Space (South Africa)

    Griffith, DJ

    2014-09-01

    Full Text Available layer. This has included all satellite data products that are relevant to the surface energy balance such as surface reflectance, temperature and emissivity. It was also important to identify active archive data services that can provide preprocessed...

  7. Qualification study of LiF flight crystals for the objective crystal spectrometer on the SPECTRUM-X-GAMMA satellite

    DEFF Research Database (Denmark)

    Christensen, Finn Erland; Rasmussen, I.; Schnopper, Herbert W.;

    1992-01-01

    The Objective Crystal Spectrometer (OXS) on the SPECTRUM-X-GAMMA satellite will carry these types of natural crystals LiF(220), Ge(111) and RAP(001). They will be used to study, among others, the H- and the He-like emission from the cosmically important elements Fe, S, Ar and O. More than 300 Li...

  8. Self-concept in adult children of schizophrenic parents: an exploratory study.

    Science.gov (United States)

    Manjula, M; Raguram, A

    2009-09-01

    Much of the work on children of schizophrenic parents has primarily focused on the risk of developing various kinds of psychiatric disorders, behavioural problems and cognitive vulnerability factors. There has been inadequate attention given to children without a clinical diagnosis and particularly the adult offspring of schizophrenic parents. It would be worthwhile to study the wellness or otherwise of these children, especially in terms of the self-concept of these individuals. To study the impact of parental mental illness on the self-concept of adult children. Thirty subjects who had one parent diagnosed as suffering from schizophrenia formed the study group, and 30 subjects, matched on age and gender with the study group, formed the control group. Subjects were assessed using a socio-demographic and clinical data sheet and a self-concept scale. The results showed that the study group had significantly poorer self-concept compared to the control group. The current clinical status of the parents had an impact on the family self-esteem of the children. Subjects who were above 10 years of age at the onset of the parental mental illness had a poorer self-concept, as compared to those who were below 10 years at the onset of illness in their parents. The results provide evidence for poor self-concept in adult children of schizophrenic parents compared to children of normal parents.

  9. Undergraduate Conceptions About What it Means to Study Something Scientifically

    Science.gov (United States)

    Nieberding, Megan; Impey, Chris; Buxner, Sanlyn; Romine, James

    2014-11-01

    Non-science major students represent individuals who will become productive members of society in non-science fields including our business leaders, policy makers, and teachers. Their college non-major science courses are often the last formal instruction they will receive in science. As such, it important to understand what students already know about science and provide instruction that is engaging and helps them gain a greater appreciation for doing science. We report on a study of almost 12,000 undergraduate students enrolled in introduction astronomy courses from 1989 - 2014, most of who were freshman or sophomore students. Almost every year during the 25 year period, students were asked to complete an in-class survey that included basic science content questions and attitude towards science questions. They were also asked to write a response to the question, “What does it mean to study something scientifically?”Sixty-five percent of responses were meaningful and considered to be on target. In their responses 16% of students described science as a way of gaining knowledge or learning about something. Twenty three percent of respondents described science as using observations or experimentation and 10% described it as involving a hypothesis. Only 8% of respondents mentioned data analysis while 6% described using data or evidence. Four percent of respondents mentioned science was a way to solve problems and 4% described science as being systematic. Students who were self-reported STEM majors (Pre-med, engineering, math, and science majors) more often mentioned that science is an empirical technique as well as the use of hypotheses in science STEM majors also mentioned data twice as often as non-STEM majors in their responses. Education majors, who made up 6% of the sample, had the least descriptive answers overall, and were the group who most often not include aspects that were essential to studying science.Gathering this information has helped characterize

  10. Children's understanding of scientific concepts: A developmental study

    Science.gov (United States)

    Bickerton, Gillian Valerie

    Combining theory-oriented inquiry and research that aims to improve instruction is a major goal of neo-Piagetian theory. Within this tradition, Case's (1992) developmental model enables educational researchers to conduct a detailed analysis of the structural and conceptual changes that occur in children's representation of knowledge in different domains at various points in their development. In so doing, it is now possible for educators to first assess children's "entering competence" in a specific subject and then set developmentally realistic instructional goals. Using Case's (1992) model as a theoretical framework, a developmental study was conducted investigating children's understanding of scientific phenomena, specifically buoyancy, at the ages of 6, 8, and 10 years. The main goal was to determine whether or not children's conceptual levels of understanding change systematically with age in a progressive manner consistent with neo-Piagetian stages of development hypothesized by Case. Participants attended one elementary school in a suburban school district near Vancouver, B.C. Sixty children were individually administered a set of five buoyancy tasks that varied in level of difficulty and involved objects of different weights, shapes and sizes. Each student was asked to predict whether an object would float or sink in different liquids and to support their prediction with an explanation. Analyses using the neo-Piagetian approach of articulating the semantic and syntactic nature of children's mental structures were conducted on the students' responses. Shape, size, weight and substance were identified as the semantic components of buoyancy which are syntactically related Using Case's dimensional metric for classifying different levels of conceptual understanding of buoyancy, the results of the study confirmed that children's understanding of buoyancy did progress through the developmental sequence as hypothesized. The structural progression from

  11. Analysis of space concepts enabled by new transportation (ASCENT) study

    Science.gov (United States)

    Webber, Derek

    2002-01-01

    The ASCENT Study is evaluating all those markets (both commercial and government missions) that may be served by a future Second Generation Reusable Launch Vehicle. The markets are being analyzed, and twenty-year forecasts are being generated, in order to assist NASA in defining the attributes of the Second Generation RLV that will eventually replace the Space Shuttle. The forecasts will make possible an evaluation of alternative architectures for the Second Generation RLV, and also help assess the extent to which new commercial markets, enabled by the proposed pricing and reliability benefits of the Second Generation RLV, can contribute to the funding of the vehicle. This paper provides a status of the project at the time of the conference, and describes the way in which the markets are being treated and data is being obtained. The sectors range from the relatively well understood telecommunications markets to the newer evolving market opportunities like public space travel. .

  12. CFRP panel concept design study for the CCAT

    Science.gov (United States)

    Martin, Robert N.; Romeo, Robert C.; Kingsley, Jeffrey S.

    2006-06-01

    Under contract from the Cornell-Caltech Atacama Telescope Project (CCAT), Composite Mirror Applications, Inc. (CMA) has undertaken a feasibility design study for the use of Carbon Fiber Reinforced Plastic (CFRP) panels in forming the primary mirror surface. We review some of the past projects using CFRP panel technology for millimeter and submillimeter wavelength radio astronomy telescopes. Pros and cons of the technology are discussed. A particular panel configuration was proposed and computer modeled with finite element analysis (FEA). The technology of replicated CFRP panels for short wavelength radio astronomical telescopes is mature and cost effective. For shorter wavelengths into the IR and visible, it is becoming a very attractive alternative to traditional, heavy glass or metal technologies.

  13. Adolescents' Interpretation of the Concept of Wellness: A Qualitative Study.

    Science.gov (United States)

    Ahanonu, Ezihe Loretta; Jooste, Karien

    2016-12-01

    Introduction: This study sought to explore and describe the interpretation which adolescents ascribe to the term wellness at a selected high school in the Western Cape Province of South Africa. Methods: A qualitative research design was utilized. Nine focus-group discussions were conducted among 58 adolescents. Sample was selected purposefully and collected data was analyzed using open coding. Results: Findings reflected adolescents' interpretations of the term wellness in the realm of holistic well-being transcending the nonexistence of illness or sickness in the body. The interpretations given include: healthy living which embrace eating enough nutritious foods, exercising regularly and being actively involved in physical activities; practicing self-care habits such as personal hygiene and grooming; well-being of the mind (psychological, emotional); having a balanced personality and interpersonal processes; being focused and goal directed and spiritual well-being. Conclusion: It is imperative to consider adolescents' understandings of wellness when planning, designing, implementing and evaluating adolescent wellness programs.

  14. Analytical study of pulsed laser irradiation on some materials used for photovoltaic cells on satellites

    Directory of Open Access Journals (Sweden)

    Afaf M. Abd El-Hameed

    2015-12-01

    Full Text Available The present research concerns on the study of laser-powered solar panels used for space applications. A mathematical model representing the laser effects on semiconductors has been developed. The temperature behavior and heat flow on the surface and through a slab has been studied after exposed to nano-second pulsed laser. The model is applied on two different types of common active semiconductor materials that used for photovoltaic cells fabrication as silicon (Si, and gallium arsenide (GaAs. These materials are used for receivers’ manufacture for laser beamed power in space. Various values of time are estimated to clarify the heat flow through the material sample and generated under the effects of pulsed laser irradiation. These effects are theoretically studied in order to determine the performance limits of the solar cells when they are powered by laser radiation during the satellite eclipse. Moreover, the obtained results are carried out to optimize conversion efficiency of photovoltaic cells and may be helpful to give more explanation for layout of the light-electricity space systems.

  15. Analytical study of pulsed laser irradiation on some materials used for photovoltaic cells on satellites

    Science.gov (United States)

    Abd El-Hameed, Afaf M.

    2015-12-01

    The present research concerns on the study of laser-powered solar panels used for space applications. A mathematical model representing the laser effects on semiconductors has been developed. The temperature behavior and heat flow on the surface and through a slab has been studied after exposed to nano-second pulsed laser. The model is applied on two different types of common active semiconductor materials that used for photovoltaic cells fabrication as silicon (Si), and gallium arsenide (GaAs). These materials are used for receivers' manufacture for laser beamed power in space. Various values of time are estimated to clarify the heat flow through the material sample and generated under the effects of pulsed laser irradiation. These effects are theoretically studied in order to determine the performance limits of the solar cells when they are powered by laser radiation during the satellite eclipse. Moreover, the obtained results are carried out to optimize conversion efficiency of photovoltaic cells and may be helpful to give more explanation for layout of the light-electricity space systems.

  16. Model Based Systems Engineering on the Europa Mission Concept Study

    Science.gov (United States)

    Bayer, Todd J.; Chung, Seung; Cole, Bjorn; Cooke, Brian; Dekens, Frank; Delp, Chris; Gontijo, I.; Lewis, Kari; Moshir, Mehrdad; Rasmussen, Robert; hide

    2012-01-01

    At the start of 2011, the proposed Jupiter Europa Orbiter (JEO) mission was staffing up in expectation of becoming an official project later in the year for a launch in 2020. A unique aspect of the pre-project work was a strong emphasis and investment on the foundations of Model-Based Systems Engineering (MBSE). As so often happens in this business, plans changed: NASA's budget and science priorities were released and together fundamentally changed the course of JEO. As a result, it returned to being a study task whose objective is to propose more affordable ways to accomplish the science. As part of this transition, the question arose as to whether it could continue to afford the investment in MBSE. In short, the MBSE infusion has survived and is providing clear value to the study effort. By leveraging the existing infrastructure and a modest additional investment, striking advances in the capture and analysis of designs using MBSE were achieved. In the process, the need to remain relevant in the new environment has brought about a wave of innovation and progress. The effort has reaffirmed the importance of architecting. It has successfully harnessed the synergistic relationship of architecting to system modeling. We have found that MBSE can provide greater agility than traditional methods. We have also found that a diverse 'ecosystem' of modeling tools and languages (SysML, Mathematica, even Excel) is not only viable, but an important enabler of agility and adaptability. This paper will describe the successful application of MBSE in the dynamic environment of early mission formulation, the significant results produced and lessons learned in the process.

  17. Model Based Systems Engineering on the Europa Mission Concept Study

    Science.gov (United States)

    Bayer, Todd J.; Chung, Seung; Cole, Bjorn; Cooke, Brian; Dekens, Frank; Delp, Chris; Gontijo, I.; Lewis, Kari; Moshir, Mehrdad; Rasmussen, Robert; Wagner, Dave

    2012-01-01

    At the start of 2011, the proposed Jupiter Europa Orbiter (JEO) mission was staffing up in expectation of becoming an official project later in the year for a launch in 2020. A unique aspect of the pre-project work was a strong emphasis and investment on the foundations of Model-Based Systems Engineering (MBSE). As so often happens in this business, plans changed: NASA's budget and science priorities were released and together fundamentally changed the course of JEO. As a result, it returned to being a study task whose objective is to propose more affordable ways to accomplish the science. As part of this transition, the question arose as to whether it could continue to afford the investment in MBSE. In short, the MBSE infusion has survived and is providing clear value to the study effort. By leveraging the existing infrastructure and a modest additional investment, striking advances in the capture and analysis of designs using MBSE were achieved. In the process, the need to remain relevant in the new environment has brought about a wave of innovation and progress. The effort has reaffirmed the importance of architecting. It has successfully harnessed the synergistic relationship of architecting to system modeling. We have found that MBSE can provide greater agility than traditional methods. We have also found that a diverse 'ecosystem' of modeling tools and languages (SysML, Mathematica, even Excel) is not only viable, but an important enabler of agility and adaptability. This paper will describe the successful application of MBSE in the dynamic environment of early mission formulation, the significant results produced and lessons learned in the process.

  18. Online self-service processing system of ZY-3 satellite: a prospective study of image cloud services

    Science.gov (United States)

    Wang, Hongyan; Wang, Huabin; Shi, Shaoyu

    2015-12-01

    The strong demands for satellite images are increasing not only in professional fields, but also in the non-professionals. But the online map services with up-to-date satellite images can serve few demands. One challenge is how to provide online processing service, which need to handle real-time online data-intensive geospatial computation and visualization. Under the background of the development of cloud computing technology, the problem can be figured out partly. The other challenge is how to implement user-customized online processing without professional background and knowledge. An online self-service processing system of ZY-3 Satellite images is designed to implement an on-demand service mode in this paper. It will work with only some simple parameters being set up for the non-professionals without having to care about the specific processing steps. And the professionals can assemble the basic processing services to a service chain, which can work out a more complex processing and a better result. This intelligent self-service online system for satellite images processing, which is called the prototype of satellite image cloud service in this paper, is accelerated under the development of cloud computing technology and researches on data-intensive computing. To realize the goal, the service mode and framework of the online self-service processing system of ZY-3 Satellite images are figured out in this paper. The details of key technologies are also discussed, including user space virtualization management, algorithm-level parallel image processing, image service chain construction, etc. And the experimental system is built up as a prospective study of image cloud services.

  19. Adolescents’ Interpretation of the Concept of Wellness: A Qualitative Study

    Directory of Open Access Journals (Sweden)

    Ezihe Loretta Ahanonu

    2016-12-01

    Full Text Available Introduction: This study sought to explore and describe the interpretation which adolescents ascribe to the term wellness at a selected high school in the Western Cape Province of South Africa. Methods: A qualitative research design was utilized. Nine focus-group discussions were conducted among 58 adolescents. Sample was selected purposefully and collected data was analyzed using open coding. Results: Findings reflected adolescents’ interpretations of the term wellness in the realm of holistic well-being transcending the nonexistence of illness or sickness in the body. The interpretations given include: healthy living which embrace eating enough nutritious foods, exercising regularly and being actively involved in physical activities; practicing self-care habits such as personal hygiene and grooming; well-being of the mind (psychological, emotional; having a balanced personality and interpersonal processes; being focused and goal directed and spiritual well-being. Conclusion: It is imperative to consider adolescents’ understandings of wellness when planning, designing, implementing and evaluating adolescent wellness programs.

  20. Advanced transportation system study: Manned launch vehicle concepts for two way transportation system payloads to LEO

    Science.gov (United States)

    Duffy, James B.

    1993-12-01

    The purpose of the Advanced Transportation System Study (ATSS) task area 1 study effort is to examine manned launch vehicle booster concepts and two-way cargo transfer and return vehicle concepts to determine which of the many proposed concepts best meets NASA's needs for two-way transportation to low earth orbit. The study identified specific configurations of the normally unmanned, expendable launch vehicles (such as the National Launch System family) necessary to fly manned payloads. These launch vehicle configurations were then analyzed to determine the integrated booster/spacecraft performance, operations, reliability, and cost characteristics for the payload delivery and return mission. Design impacts to the expendable launch vehicles which would be required to perform the manned payload delivery mission were also identified. These impacts included the implications of applying NASA's man-rating requirements, as well as any mission or payload unique impacts. The booster concepts evaluated included the National Launch System (NLS) family of expendable vehicles and several variations of the NLS reference configurations to deliver larger manned payload concepts (such as the crew logistics vehicle (CLV) proposed by NASA JSC). Advanced, clean sheet concepts such as an F-1A engine derived liquid rocket booster (LRB), the single stage to orbit rocket, and a NASP-derived aerospace plane were also included in the study effort. Existing expendable launch vehicles such as the Titan 4, Ariane 5, Energia, and Proton were also examined. Although several manned payload concepts were considered in the analyses, the reference manned payload was the NASA Langley Research Center's HL-20 version of the personnel launch system (PLS). A scaled up version of the PLS for combined crew/cargo delivery capability, the HL-42 configuration, was also included in the analyses of cargo transfer and return vehicle (CTRV) booster concepts. In addition to strictly manned payloads, two-way cargo

  1. A Study of Concept Mapping as an Instructional Intervention in an Undergraduate General Chemistry Calorimetry Laboratory

    Science.gov (United States)

    Stroud, Mary W.

    This investigation, rooted in both chemistry and education, considers outcomes occurring in a small-scale study in which concept mapping was used as an instructional intervention in an undergraduate calorimetry laboratory. A quasi-experimental, multiple-methods approach was employed since the research questions posed in this study warranted the use of both qualitative and quantitative perspectives and evaluations. For the intervention group of students, a convenience sample, post-lab concept maps, written discussions, quiz responses and learning surveys were characterized and evaluated. Archived quiz responses for non-intervention students were also analyzed for comparison. Students uniquely constructed individual concept maps containing incorrect, conceptually correct and "scientifically thin" calorimetry characterizations. Students more greatly emphasized mathematical relationships and equations utilized during the calorimetry experiment; the meaning of calorimetry concepts was demonstrated to a lesser extent.

  2. RESEARCH REPORT: Definitions of Physical Concepts: A study of physics teachers' knowledge and views

    Science.gov (United States)

    Galili, Igal; Lehavi, Yaron

    2006-04-01

    A study was made of the ability of a population of high-school physics teachers to define physics concepts and of their views regarding the importance of such definitions. It was found possible to arrange the definitions accumulated in categories, and the classification so obtained was consonant with that of the philosophy of science. Although the subjects of this study were experienced teachers, the definitions they supplied exhibited shortcomings. Despite this, however, the teachers attached great importance to a knowledge of concept definitions. The implications of these findings in connection with the ongoing debate regarding the importance of concept definitions in science education are discussed. The high educational value of concept definitions is argued and a deficiency in this knowledge points to the shortcoming in teacher training.

  3. Managing Expectations in the Transition to Proof of Concept Studies.

    Science.gov (United States)

    Kieber-Emmons, Thomas; Makhoul, Issam; Pennisi, Angela; Siegel, Eric R; Emanuel, Peter D; Monzavi-Karbassi, Bejotaloh; Steplewski, Zenon; Beck, J Thaddeus; Hutchins, Laura F

    2017-01-01

    As we move away from the traditional chemotherapy era to targeted therapy, the validity of old assessment paradigms associated with therapeutics are being raised in the context of immunotherapy. The old paradigm required elaborating on the toxicity assessment, with no expectation of efficacy in early phase trials. Safety data from Phase 1 and 2 studies with many immunotherapeutics show limited toxicities and draw attention to the need to demonstrate efficacy in the early evaluation of new agents. Literature searches indicate that molecular oncology mechanistic-based agents are being linked with molecular disease status and clinical benefit. Biomarkers and other endpoints are being employed to accomplish this. Perspectives for a meaningful context of integrating biomarkers and clinical trial design are reviewed. The design and conduct of clinical trials have not been fully adjusted to the new era of personalized oncology, and so we are in transition. A part of this transition is the management of expectations and trial designs that need to be considered relative to preclinical experience in the development of therapeutics. For example, pathological complete response is now considered a surrogate marker for favorable prognosis in breast cancer patients who are treated in the neoadjuvant setting. This surrogate marker is tied to novel agents' mechanistic characteristics with no preclinical counterpart. The old paradigm considers patients equal with similar chances to respond to treatments, but the new paradigm considers patient's heterogeneity, a major fact that informs the design of clinical trials. By linking every treatment to a mechanism of action and to the presence of a specific biomarker, new trials are going to have more subjects who are likely to respond to the treatment. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  4. The small satellite NINA-MITA to study galactic and solar cosmic rays in low-altitude polar orbit

    Science.gov (United States)

    Furano, G.; Bidoli, V.; Casolino, M.; de Pascale, M. P.; Iannucci, A.; Morselli, A.; Picozza, P.; Reali, E.; Sparvoli, R.; Bakaldin, A.; Galper, A.; Koldashov, M.; Korotkov, M.; Leonov, A.; Mikhailov, V.; Murashov, A.; Voronov, S.; Mazzenga, G.; Ricci, M.; Castellini, G.; Barbiellini, M.; Boezio, M.; Bonvicini, V.; Cirami, R.; Vacchi, A.; Zampa, N.; Ambriola, M.; Bellotti, R.; Cafagna, F.; Ciacio, F.; Circella, M.; de Marzo, C.; Adriani, O.; Papini, P.; Piccardi, S.; Spillantini, P.

    The satellite MITA, carrying on board the scientific payload NINA-2, was launched on July the 15th, 2000 from the cosmodrome of Plesetsk (Russia) with a Cosmos-3M rocket. The satellite and the payload are currently operating within nominal parameters. NINA-2 is the first scientific payload for the technological flight of the Italian small satellite MITA. The detector used in this mission is identical to the one already flying on the Russian satellite Resurs-O1 n.4 in a 840-km sun-synchronous orbit, but makes use of the extensive computer and telemetry capabilities of MITA bus to improve the active data acquisition time. NINA physics objectives are to study cosmic nuclei from hydrogen to iron in the energy range between 10 MeV/n and 1 GeV/n during the years 2000-2003, that is the solar maximum period. The device is capable of charge identification up to iron with isotope sensitivity up to oxigen. The 87.3 degrees, 460 km altitude polar orbit allows investigations of cosmic rays of solar and galactic origin, so to study long and short term solar transient phenomena, and the study of the trapped radiation at higher geomagnetic cutoff.

  5. The availability and accessibility of basic concept vocabulary in AAC software: a preliminary study.

    Science.gov (United States)

    McCarthy, Jillian H; Schwarz, Ilsa; Ashworth, Morgan

    2017-09-01

    Core vocabulary lists obtained through the analyses of children's utterances include a variety of basic concept words. Supporting young children who use augmentative and alternative communication (AAC) to develop their understanding and use of basic concepts is an area of practice that has important ramifications for successful communication in a classroom environment. This study examined the availability of basic concept words across eight frequently used, commercially available AAC language systems, iPad© applications, and symbol libraries used to create communication boards. The accessibility of basic concept words was subsequently examined using two AAC language page sets and two iPad applications. Results reveal that the availability of basic concept words represented within the different AAC language programs, iPad applications, and symbol libraries varied but was limited across programs. However, there is no significant difference in the accessibility of basic concept words across the language program page sets or iPad applications, generally because all of them require sophisticated motor and cognitive plans for access. These results suggest that educators who teach or program vocabulary in AAC systems need to be mindful of the importance of basic concept words in classroom settings and, when possible, enhance the availability and accessibility of these words to users of AAC.

  6. Relationships between lightning activity and various thundercloud parameters: satellite and modelling studies

    Science.gov (United States)

    Baker, M. B.; Blyth, A. M.; Christian, H. J.; Latham, J.; Miller, K. L.; Gadian, A. M.

    The lightning frequency model developed by Baker et al. [Baker, M.B., Christian, H.J., Latham, J., 1995. A computational study of the relationships linking lightning frequency and other thundercloud parameters, Q. J. R. Meteorol. Soc., 121, 1525-1548] has been refined and extended, in an effort to provide a more realistic framework from which to examine computationally the relationships that might exist between lightning frequency f (which is now being routinely measured from a satellite, using the NASA/MSFC Optical Transient Detector (OTD)) and a variety of cloud physical parameters. Specifically, superior or more comprehensive representations were utilised of: (1) glaciation via the Hallett-Mossop (H-M) process; (2) the updraught structure of the model cloud; (3) the liquid-water-content structure of the model cloud; (4) the role of the reversal temperature Trev in influencing lightning characteristics; (5) the critical breakdown field for lightning initiation; and (6) the electrical characteristics of the ice crystal anvil of the model cloud. Although our extended studies yielded some new insights into the problem, the basic pattern of relationships between f and the other parameters was very close to that reported by Baker et al. (1995). The more elaborate treatment of Trev restricted somewhat the range of conditions under which reverse-polarity lightning could be produced if the cloud glaciated via H-M, but confirmed the earlier conclusion that such lightning would not occur if the glaciation was of the Fletcher type. The computations yielded preliminary support for the hypothesis that satellite measurements of f might be used to determine values of the ice-content of cumulonimbus anvils: a parameter of climatological importance. The successful launch and continuing satisfactory functioning of the OTD [Christian, H.J., Goodman, S., 1992. Global observations of lightning from space, Proc. 9th Int. Conf. on Atmospheric Electricity, St. Petersburg, pp. 316

  7. Space station automation study. Automation requirements derived from space manufacturing concepts. Volume 1: Executive summary

    Science.gov (United States)

    1984-01-01

    The two manufacturing concepts developed represent innovative, technologically advanced manufacturing schemes. The concepts were selected to facilitate an in depth analysis of manufacturing automation requirements in the form of process mechanization, teleoperation and robotics, and artificial intelligence. While the cost effectiveness of these facilities has not been analyzed as part of this study, both appear entirely feasible for the year 2000 timeframe. The growing demand for high quality gallium arsenide microelectronics may warrant the ventures.

  8. Study on ABCD Analysis Technique for Business Models, business strategies, Operating Concepts & Business Systems

    OpenAIRE

    Aithal, Sreeramana

    2016-01-01

    Studying the implications of a business model, choosing success strategies, developing viable operational concepts or evolving a functional system, it is important to analyse it in all dimensions. For this purpose, various analysing techniques/frameworks are used. This paper is a discussion on how to use an innovative analysing framework called ABCD model on a given business model, or on a business strategy or a operational concept/idea or business system. Based on four constructs Advantages,...

  9. Comparative Study of Ground Measured, Satellite-Derived, and Estimated Global Solar Radiation Data in Nigeria

    Directory of Open Access Journals (Sweden)

    Boluwaji M. Olomiyesan

    2016-01-01

    Full Text Available In this study, the performance of three global solar radiation models and the accuracy of global solar radiation data derived from three sources were compared. Twenty-two years (1984–2005 of surface meteorological data consisting of monthly mean daily sunshine duration, minimum and maximum temperatures, and global solar radiation collected from the Nigerian Meteorological (NIMET Agency, Oshodi, Lagos, and the National Aeronautics Space Agency (NASA for three locations in North-Western region of Nigeria were used. A new model incorporating Garcia model into Angstrom-Prescott model was proposed for estimating global radiation in Nigeria. The performances of the models used were determined by using mean bias error (MBE, mean percentage error (MPE, root mean square error (RMSE, and coefficient of determination (R2. Based on the statistical error indices, the proposed model was found to have the best accuracy with the least RMSE values (0.376 for Sokoto, 0.463 for Kaduna, and 0.449 for Kano and highest coefficient of determination, R2 values of 0.922, 0.938, and 0.961 for Sokoto, Kano, and Kaduna, respectively. Also, the comparative study result indicates that the estimated global radiation from the proposed model has a better error range and fits the ground measured data better than the satellite-derived data.

  10. Study on the volcanic ash cloud with Feng Yun-3 meteorological satellite data

    Science.gov (United States)

    Gong, Cai-lan T.; Jiang, Shan; Hu, Yong; Meng, Peng

    2013-09-01

    Volcano eruption can produce a mass of volcanic ash floating in the air for a long period, which will seriously threaten the aerial planes safety, and cause the air pollution, it could do harm to people's living environment and their health. Take the Iceland Eyjafjallajokull volcano as an example which erupted in April to May 2010, the volcano ash cloud were derived with the visible and infrared scanning radiometer of FengYun-3(FY-3 VIRR) meteorological satellite data. The medium wave infrared (MWIR) and the thermal infrared split windows (THIR-SW) data were used separately. the MODIS THIR-SW data were also be used to retrieve ash cloud to test the results derived from FY-3 VIRR data. It showed that the MWIR was more applicable for the ash cloud retrieving than the THIR-SW with FY-3 VIRR data, and the threshold value should be adjusted to around negative 1 rather than 0 for VIRR THIR-SW data. And the threshold should be adjusted with the THIR-SW of FY-3. The ash cloud radiation and bright temperature(BT), spatial distribution characteristics were also analyzed quantitatively with the two channels data. The study could provide parameters for the prediction of volcanic ash cloud dispersion simulate. When the real temperature of lava flow were high enough, the sensor will show a false bright temperature, how to retrieve the real temperature of the higher lava flow is a problem need to be studied in the future.

  11. Real time deforestation detection using ann and satellite images the Amazon rainforest study case

    CERN Document Server

    Nunes Kehl, Thiago; Roberto Veronez, Maurício; Cesar Cazella, Silvio

    2015-01-01

    The foremost aim of the present study was the development of a tool to detect daily deforestation in the Amazon rainforest, using satellite images from the MODIS/TERRA sensor and Artificial Neural Networks. The developed tool provides parameterization of the configuration for the neural network training to enable us to select the best neural architecture to address the problem. The tool makes use of confusion matrices to determine the degree of success of the network. A spectrum-temporal analysis of the study area was done on 57 images from May 20 to July 15, 2003 using the trained neural network. The analysis enabled verification of quality of the implemented neural network classification and also aided in understanding the dynamics of deforestation in the Amazon rainforest, thereby highlighting the vast potential of neural networks for image classification. However, the complex task of detection of predatory actions at the beginning, i.e., generation of consistent alarms, instead of false alarms has not bee...

  12. Studying bio-thermal effects at and around MSW dumps using Satellite Remote Sensing and GIS.

    Science.gov (United States)

    Mahmood, Khalid; Batool, Syeda Adila; Chaudhry, Muhammad Nawaz

    2016-09-01

    Estimating negative impacts of MSW dumps on its surrounding environment is the key requirement for any remedial measures. This study has been undertaken to map bio-thermal effects of MSW dumping at and around dumping facilities (non-engineered) using satellite imagery for Faisalabad, Pakistan. Thirty images of Landsat 8 have been selected after validation for the accuracy of their observational details from April 2013 to October 2015. Land Surface Temperature (LST), NDVI, SAVI and MSAVI have been derived from these images through Digital Image Processing (DIP) and have been subjected to spatio-temporal analysis in GIS environment. MSW dump has been found with average temperature elevation of 4.3K and 2.78K from nearby agriculture land and urban settlement respectively. Vegetation health has been used as the bio-indicator of MSW effects and is implemented through NDVI, SAVI, MSAVI. Spatial analyses have been used to mark boundary of bio-thermally affected zone around dumped MSW and measure 700m. Seasonal fluctuations of elevated temperatures and boundary of the bio-thermally affected zones have also been discussed. Based on the direct relation found between vegetation vigor and the level of deterioration within the bio-thermally affected region, use of crops with heavy vigor is recommended to study MSW hazard influence using bio-indicators of vegetation health.

  13. Capturing Pre-Service Social Studies Teachers' Perceptions about the Concept of Election through Metaphor Analysis

    Science.gov (United States)

    Hamarat, Ercenk

    2016-01-01

    The aim of this study is to analyze the perception of pre-service social studies teachers (PSSTs) about the concept of election via metaphors. A study group of this work consisted of 61 PSSTs from Nigde University, Faculty of Education, Social Studies Teaching Department. Implementation and data collection was done in 2014 to 2015 academic year.…

  14. Study of the comparative costs of five wet/dry cooling tower concepts

    Energy Technology Data Exchange (ETDEWEB)

    Zaloudek, F.R.; Allemann, R.T.; Faletti, D.W.; Johnson, B.M.; Parry, H.L.; Smith, G.C.; Tokarz, R.D.; Walter, R.A.

    1976-09-01

    The projected cost of five alternative dry/wet power plant heat rejection concepts was studied under conditions imposed by hypothetical use in association with the San Juan Plant Unit 3, a 550-MWe facility currently under construction near the ''Four Corners'' area of New Mexico. The five alternative concepts were: integrated dry/wet tower; separate dry and wet towers; metal fin-tube induced draft tower with deluge water augmentation; plastic heat exchanger tower with deluge water augmentation, and metal fin-tube/deluge augmentation tower with an intermediate ammonia evaporation-condensation condenser and the cooling tower. The integrated dry/wet tower concept, already chosen for service at San Juan Unit 3, was included for reference purposes. All concepts were conceptually designed and estimated using the same bases and employing uniform practices. Each concept was assumed to use all water allocated for consumptive use in Unit 3. The cost estimates obtained showed the following descending order of ''comparable capital cost'': separate dry/wet; metal fin-tube/deluge; integrated dry/wet; plastic tube/deluge; and metal fin-tube/deluge/ammonia. The results indicate that two of the advanced concepts considered, i.e., the plastic tube/deluge concept and the metal fin tube/deluge/ammonia concept, can possibly reduce the overall costs of dry/wet cooling under conditions imposed by the site considered. It was recommended that these two concepts receive additional attention by the ERDA Dry Cooling Tower Program and industry to further quantify their potential benefits and demonstrate their performance and reliability.

  15. [Self-concept level in children with burns sequelae: A comparative study].

    Science.gov (United States)

    Castillo C, Carmen; Santander M, Dolores; Solís F, Fresia

    2015-01-01

    Self-concept is the set of ideas and attitudes that a person has about him/herself. To evaluate whether there are differences in the level of self-concept in children 8-12 years old with and without burns sequelae. To identify predictive variables of self-concept in children with sequelae. A comparative cross-sectional study of self-concept in 109 children with burns sequelae, from 8 to 12 years old, with 109 children without burns sequelae, and of the same age and socioeconomic status. The Piers-Harris self-concept scale is used, which provides a general measurement of self-concept and behavioural, intellectual and school status, appearance, and physical attributes, anxiety, popularity, happiness and satisfaction dimensions. There were no significant differences in the level of general self-concept or their dimensions (P>.05). In the group with burns sequelae, the protective factor was the variable number of sequels was associated with the dimensions of anxiety, popularity, happiness-satisfaction and general self-concept. The location variable emerged as a risk factor for the behavioural dimension. The absence of differences in self-concept between children with burns sequelae and children without them is similar to that reported in the literature. The finding in the risk and protective factors encourages to further research, and perhaps incorporating pre-morbidity and family background. Copyright © 2015 Sociedad Chilena de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

  16. Secondary school physics teachers' conceptions of scientific evidence: An exploratory case study

    Science.gov (United States)

    Taylor, Joseph A.; Dana, Thomas M.

    2003-10-01

    This article describes an exploratory case study of secondary school physics teachers' conceptions of scientific evidence. The nature of teachers' conceptions of evidence was derived from an analysis of data collected from 1 preservice and 2 in-service teachers. Each teacher responded to a series of research prompts in multiple interviews and handwritten tasks. In these research prompts, the teachers thought aloud while designing experiments and critically evaluating student-collected data as presented in hypothetical classroom scenarios. Spoken and written data were recorded. The data set was coded and analyzed using standard qualitative analysis techniques. Data from this study suggest that, while contemplating the reliability and validity of hypothetical student-generated scientific evidence, the teachers frequently intertwined conceptions of evidence with subject matter concepts centrally relevant to the hypothetical investigation. Data also indicate that the relationship between subject matter knowledge and conceptions of evidence was more pronounced for some conceptions of evidence than for others. Results suggest that a fuller study is warranted. Suggestions for future research include exploring such relationships in other physics content areas as well as other scientific disciplines. Implications for science teacher education suggest that science and science methods courses should encourage preservice teachers to engage in original scientific research, as well as participate in peer review and critique.

  17. Several thoughts for using new satellite remote sensing and global modeling for aerosol and cloud climate studies

    Science.gov (United States)

    Nakajima, Teruyuki; Hashimoto, Makiko; Takenaka, Hideaki; Goto, Daisuke; Oikawa, Eiji; Suzuki, Kentaroh; Uchida, Junya; Dai, Tie; Shi, Chong

    2017-04-01

    The rapid growth of satellite remote sensing technologies in the last two decades widened the utility of satellite data for understanding climate impacts of aerosols and clouds. The climate modeling community also has received the benefit of the earth observation and nowadays closed-collaboration of the two communities make us possible to challenge various applications for societal problems, such as for global warming and global-scale air pollution and others. I like to give several thoughts of new algorithm developments, model use of satellite data for climate impact studies and societal applications related with aerosols and clouds. Important issues are 1) Better aerosol detection and solar energy application using expanded observation ability of the third generation geostationary satellites, i.e. Himawari-8, GOES-R and future MTG, 2) Various observation functions by directional, polarimetric, and high resolution near-UV band by MISR, POLDER&PARASOL, GOSAT/CAI and future GOSAT2/CAI2, 3) Various applications of general purpose-imagers, MODIS, VIIRS and future GCOM-C/SGLI, and 4) Climate studies of aerosol and cloud stratification and convection with active and passive sensors, especially climate impact of BC aerosols using CLOUDSAT&CALIPSO and future Earth Explorer/EarthCARE.

  18. Preface to the Special Issue on "Geophysical and Climate Change Studies in Tibet, Xinjiang, and Siberia (TibXS from Satellite Geodesy"

    Directory of Open Access Journals (Sweden)

    Cheinway Hwang

    2013-01-01

    Full Text Available This special issue publishes papers on recent results in geophysical and climate change studies over Tibet, Xinjiang and Siberia (TibXS based upon some of the key sensors used in satellite geodesy, including satellite gravimetric sensors (GRACE and GOCE, satellite altimeters (TOPEX, Jason-1 and -2, and ENVISAT, and Global Positioning System satellites. Results from ground- and airborne-based geodetic observations, notably those based on airborne gravimeter, superconducting gravimeter (SG and seismometers are also included in the special issue. In all, 22 papers were submitted for this special issue; 17 papers were accepted.

  19. Integration of environmental simulation models with satellite remote sensing and geographic information systems technologies: case studies

    Science.gov (United States)

    Steyaert, Louis T.; Loveland, Thomas R.; Brown, Jesslyn F.; Reed, Bradley C.

    1993-01-01

    Environmental modelers are testing and evaluating a prototype land cover characteristics database for the conterminous United States developed by the EROS Data Center of the U.S. Geological Survey and the University of Nebraska Center for Advanced Land Management Information Technologies. This database was developed from multi temporal, 1-kilometer advanced very high resolution radiometer (AVHRR) data for 1990 and various ancillary data sets such as elevation, ecological regions, and selected climatic normals. Several case studies using this database were analyzed to illustrate the integration of satellite remote sensing and geographic information systems technologies with land-atmosphere interactions models at a variety of spatial and temporal scales. The case studies are representative of contemporary environmental simulation modeling at local to regional levels in global change research, land and water resource management, and environmental simulation modeling at local to regional levels in global change research, land and water resource management and environmental risk assessment. The case studies feature land surface parameterizations for atmospheric mesoscale and global climate models; biogenic-hydrocarbons emissions models; distributed parameter watershed and other hydrological models; and various ecological models such as ecosystem, dynamics, biogeochemical cycles, ecotone variability, and equilibrium vegetation models. The case studies demonstrate the important of multi temporal AVHRR data to develop to develop and maintain a flexible, near-realtime land cover characteristics database. Moreover, such a flexible database is needed to derive various vegetation classification schemes, to aggregate data for nested models, to develop remote sensing algorithms, and to provide data on dynamic landscape characteristics. The case studies illustrate how such a database supports research on spatial heterogeneity, land use, sensitivity analysis, and scaling issues

  20. Relationships between intrinsic motivation, physical self-concept and satisfaction with life: a longitudinal study.

    Science.gov (United States)

    Martín-Albo, José; Núñez, Juan L; Domínguez, Evelia; León, Jaime; Tomás, José M

    2012-01-01

    In this study, we examined the relationships between intrinsic motivation, physical self-concept, and satisfaction with life using cross-lagged panel models analysed via structural equation models. The sample consisted of 293 participants (148 men, 145 women) aged 18-70 years who performed diverse types of physical exercise. Three alternative models were tested. The data were better represented by a model in which physical self-concept mediates the relationships between intrinsic motivation and satisfaction with life. Specifically, the direct effects of intrinsic motivation on physical self-concept, and of physical self-concept on satisfaction with life were significant, with the amount of explained variance increasing over time. In conclusion, people who perform physical exercise regularly, and who have fun over time will tend to have a better physical self-perception and, consequently, more psychological well-being.

  1. Longitudinal study of preadolescent sport self-concept and performance: reciprocal effects and causal ordering.

    Science.gov (United States)

    Marsh, Herbert W; Gerlach, Erin; Trautwein, Ulrich; Lüdtke, Oliver; Brettschneider, Wolf-Dietrich

    2007-01-01

    Do preadolescent sport self-concepts influence subsequent sport performance? Longitudinal data (Grades 3, 4, and 6) for young boys and girls (N= 1,135; mean age = 9.67) were used to test reciprocal effects model (REM) predictions that sport self-concept is both a cause and a consequence of sport accomplishments. Controlling prior sport performance (performance-based measures and teacher assessments), prior sport self-concept had positive effects on subsequent sport performance in both Grade 4 and Grade 6 and for both boys and girls. Coupled with previous REM studies of adolescents in the academic domain, this first test for preadolescents in the sport domain supports the generalizability of REM predictions over gender, self-concept domain, preadolescent ages, and the transition from primary to secondary school.

  2. Preliminary study on direct assimilation of cloud-affected satellite microwave brightness temperatures

    Science.gov (United States)

    Zhang, Sibo; Guan, Li

    2017-02-01

    Direct assimilation of cloud-affected microwave brightness temperatures from AMSU-A into the GSI three-dimensional variational (3D-Var) assimilation system is preliminarily studied in this paper. A combination of cloud microphysics parameters retrieved by the 1D-Var algorithm (including vertical profiles of cloud liquid water content, ice water content, and rain water content) and atmospheric state parameters from objective analysis fields of an NWP model are used as background fields. Three cloud microphysics parameters (cloud liquid water content, ice water content, and rain water content) are applied to the control variable. Typhoon Halong (2014) is selected as an example. The results show that direct assimilation of cloud-affected AMSU-A observations can effectively adjust the structure of large-scale temperature, humidity and wind analysis fields due to the assimilation of more AMSU-A observations in typhoon cloudy areas, especially typhoon spiral cloud belts. These adjustments, with temperatures increasing and humidities decreasing in the movement direction of the typhoon, bring the forecasted typhoon moving direction closer to its real path. The assimilation of cloud-affected satellite microwave brightness temperatures can provide better analysis fields that are more similar to the actual situation. Furthermore, typhoon prediction accuracy is improved using these assimilation analysis fields as the initial forecast fields in NWP models.

  3. Application of Satellite-Based Spectrally-Resolved Solar Radiation Data to PV Performance Studies

    Directory of Open Access Journals (Sweden)

    Ana Maria Gracia Amillo

    2015-04-01

    Full Text Available In recent years, satellite-based solar radiation data resolved in spectral bands have become available. This has for the first time made it possible to produce maps of the geographical variation in the solar spectrum. It also makes it possible to estimate the influence of these variations on the performance of photovoltaic (PV modules. Here, we present a study showing the magnitude of the spectral influence on PV performance over Europe and Africa. The method has been validated using measurements of a CdTe module in Ispra, Italy, showing that the method predicts the spectral influence to within ±2% on a monthly basis and 0.1% over a 19-month period. Application of the method to measured spectral responses of crystalline silicon, CdTe and single-junction amorphous silicon (a-Si modules shows that the spectral effect is smallest over desert areas for all module types, higher in temperate Europe and highest in tropical Africa, where CdTe modules would be expected to yield +6% and single- junction a-Si modules up to +10% more energy due to spectral effects. In contrast, the effect for crystalline silicon modules is less than ±1% in nearly all of Africa and Southern Europe, rising to +1% or +2% in Northern Europe.

  4. Object-oriented industrial solid waste identification using HJ satellite imagery: a case study of phosphogypsum

    Science.gov (United States)

    Fu, Zhuo; Shen, Wenming; Xiao, Rulin; Xiong, Wencheng; Shi, Yuanli; Chen, Baisong

    2012-10-01

    The increasing volume of industrial solid wastes presents a critical problem for the global environment. In the detection and monitoring of these industrial solid wastes, the traditional field methods are generally expensive and time consuming. With the advantages of quick observations taken at a large area, remote sensing provides an effective means for detecting and monitoring the industrial solid wastes in a large scale. In this paper, we employ an object-oriented method for detecting the industrial solid waste from HJ satellite imagery. We select phosphogypsum which is a typical industrial solid waste as our target. Our study area is located in Fuquan in Guizhou province of China. The object oriented method we adopted consists of the following steps: 1) Multiresolution segmentation method is adopted to segment the remote sensing images for obtaining the object-based images. 2) Build the feature knowledge set of the object types. 3) Detect the industrial solid wastes based on the object-oriented decision tree rule set. We analyze the heterogeneity in features of different objects. According to the feature heterogeneity, an object-oriented decision tree rule set is then built for aiding the identification of industrial solid waste. Then, based on this decision tree rule set, the industrial solid waste can be identified automatically from remote sensing images. Finally, the identified results are validated using ground survey data. Experiments and results indicate that the object-oriented method provides an effective method for detecting industrial solid wastes.

  5. Self-Concept in Student Learning and Motivation Truant : Descriptive-Correlational Studies

    Directory of Open Access Journals (Sweden)

    Erlina Harahap

    2017-08-01

    Full Text Available This research is aimed describ the learning motivation and self-concept of students who truant. This study used a descriptive quantitative method. The research conducted by the students of SMAN 5 Padangsidimpuan in the period of 2015/2016 with the total of the population was 420 students. Amount of research sample was 36 students and had been chosen by using purposive sampling technique. An instrument employed in this study was a Likert-scaled questionnaire. Data were analyzed by using percentage technique and the relationship between the two variables was analyzed by using nonparametric statistic, that is Spearman’s Coefficient of Rank Correlation. Results of this research are just like the following: 1 participants’ level of achievement on self-concept of students who truant is about 69,8%, 2 participants’ level of achievement on learning motivation of students who truant is about 69,2%, and 3 correlation coefficient of self-concept and learning motivation of students who truant is about 0,581. Therefore, it can be concluded that students who truancy have very low self-concept and learning motivation, and there is a significant relationship between self-concept and learning motivation. The implication in guidance counseling services is to create a service program which can increase self-concept and be learning motivation of students who truant

  6. Family Communication about Donor Conception: A Qualitative Study with Lesbian Parents.

    Science.gov (United States)

    Van Parys, Hanna; Wyverkens, Elia; Provoost, Veerle; De Sutter, Petra; Pennings, Guido; Buysse, Ann

    2016-03-01

    In this qualitative study of 10 lesbian couples who built their families through anonymous donor conception, we explore how lesbian parents experience communication about the donor conception within the family. While for these families "disclosure" of donor conception is often seen as evident, the way parents and children discuss this subject and how this is experienced by the parents themselves has not received much research attention. To meet this gap in the literature, in-depth interviews with lesbian couples were conducted. An Interpretative Phenomenological Analysis showed that this family communication process can be understood within the broader relational context of parent-child relationships. Even though parents handled this family communication in many different ways, these were all inspired by the same motives: acting in the child's best interest and-on a more implicit level-maintaining good relations within the family. Furthermore, parents left the initiative for talking about the DC mostly to the child. Overall, parents aimed at constructing a donor conception narrative that they considered acceptable for both the children and themselves. They used different strategies, such as gradual disclosure, limiting the meaning of the donor, and justifying the donor conception. Building an acceptable donor conception narrative was sometimes challenged by influences from the social environment. In the discussion, we relate this qualitative systemic study to the broader issues of selective disclosure and bidirectionality within families.

  7. Building technological capability within satellite programs in developing countries

    Science.gov (United States)

    Wood, Danielle; Weigel, Annalisa

    2011-12-01

    outside the space arena in which organizations have pursued technological capability. Scholars have analyzed these examples and developed insightful frameworks. The paper draws key concepts from this literature about the nature of development, technology, knowledge and organizational learning. These concepts are relevant to learning in new satellite programs, but the ideas must be applied cautiously because of the nature of satellite technology. The paper draws three major lessons from the international development literature regarding absorptive capacity, tacit knowledge and organizational learning; it synthesizes these lessons into a cohesive, original framework. The closing section proposes future work on a detailed study of technological learning in specific government satellite programs.

  8. 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....

  9. Pre-Service Teachers' Conceptions on Use of Social Media in Social Studies Education

    Science.gov (United States)

    Kahveci, Nihat Gürel

    2015-01-01

    The use of social media is tremendously increasing trend for personal use. At the same time, social media are penetrating to the educational settings as well. Thus purpose of this study is to investigate pre-service social studies teachers' conceptions on use of social media in social studies education; it is possible implications on social…

  10. Pre-Service Teachers' Conceptions on Use of Social Media in Social Studies Education

    Science.gov (United States)

    Kahveci, Nihat Gürel

    2015-01-01

    The use of social media is tremendously increasing trend for personal use. At the same time, social media are penetrating to the educational settings as well. Thus purpose of this study is to investigate pre-service social studies teachers' conceptions on use of social media in social studies education; it is possible implications on social…

  11. A Study of Seventh-Graders Comprehensions of Human Reproduction Concepts

    Science.gov (United States)

    Barrow, Lloyd Harley

    1977-01-01

    Study of an Iowa junior high school revealed that: (1) seventh grade pupils' knowledge levels were raised after studying human reproduction concepts and that (2) the pupils were of the opinion that human reproduction studies should be included in life science classes. (MB)

  12. 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.

  13. Flood modelling with global precipitation measurement (GPM) satellite rainfall data: a case study of Dehradun, Uttarakhand, India

    Science.gov (United States)

    Sai Krishna, V. V.; Dikshit, Anil Kumar; Pandey, Kamal

    2016-05-01

    Urban expansion, water bodies and climate change are inextricably linked with each other. The macro and micro level climate changes are leading to extreme precipitation events which have severe consequences on flooding in urban areas. Flood simulations shall be helpful in demarcation of flooded areas and effective flood planning and preparedness. The temporal availability of satellite rainfall data at varying spatial scale of 0.10 to 0.50 is helpful in near real time flood simulations. The present research aims at analysing stream flow and runoff to monitor flood condition using satellite rainfall data in a hydrologic model. The satellite rainfall data used in the research was NASA's Integrated Multi-satellite Retrievals for Global Precipitation Measurement (IMERG), which is available at 30 minutes temporal resolution. Landsat data was used for mapping the water bodies in the study area. Land use land cover (LULC) data was prepared using Landsat 8 data with maximum likelihood technique that was provided as an input to the HEC-HMS hydrological model. The research was applied to one of the urbanized cities of India, viz. Dehradun, which is the capital of Uttarakhand State. The research helped in identifying the flood vulnerability at the basin level on the basis of the runoff and various socio economic parameters using multi criteria analysis.

  14. The Bobath concept in stroke rehabilitation: a focus group study of the experienced physiotherapists' perspective.

    Science.gov (United States)

    Lennon, S; Ashburn, A

    2000-10-15

    The Bobath concept, usually known as neuro-developmental treatment (NDT) in America, is one of the major approaches used to rehabilitate patients following stroke; however since the last publication of Bobath (1990), the concept has been taught via an oral tradition on postgraduate courses. This study therefore aimed to explore with experienced therapists firstly how the Bobath concept had changed since 1990, and secondly what they considered its main theoretical assumptions to be using a focus group research design. Eight peer-nominated expert physiotherapists agreed to participate in two focus groups organized according to specialist interest in either neurology (group A) or elderly care (group B). Therapists were asked to discuss six topics based on a review of published literature. Data analysis involved several readings of verbatim transcriptions, from which key themes and concepts were developed. All therapists agreed on the following core themes defining Bobath: analysis of normal movement, control of tone and facilitation of movement. Neuroplasticity was described as the primary rationale for treatment with therapists using afferent information to target the damaged central nervous system. In addition group A discussed motor learning, whereas group B discussed patient focused goals and relating treatment to function. This study highlighted changes in theory, terminology, and techniques. Tone remained a major problem in the rehabilitation management of the hemiplegic patient; however much attention was also directed towards the musculoskeletal system. Both facilitation of normal movement components and task specific practice using specific manual guidance were considered critical elements of the Bobath concept. For Bobath therapists, physiotherapy has an important impact on both the performance components of movement and functional outcomes. In view of the small numbers involved in this preliminary study, further studies are now needed to determine if these

  15. Physical self-concept of adolescents in Western Balkan countries: a pilot study.

    Science.gov (United States)

    Janić, Snežana Radisavljević; Jurak, Gregor; Milanović, Ivana; Lazarević, Dušanka; Kovač, Marjeta; Novak, Dario

    2014-10-01

    The aim of this study was to explore physical self-concept of adolescents of the Western Balkans (Serbia, Slovenia, Croatia, and Bosnia and Herzegovina) according to sex and country. The participants were 2,606 students, ages 13 and 14 years (M = 13.5, SD = 0.9). The Physical Self-Description Questionnaire (PSDQ) was used to assess multidimensional physical self-concept. The results show the interaction of sex and country for three dimensions of physical self-concept (Appearance, Global Physical Self-Concept, and Self-Esteem). It was shown that female and male adolescents' perception of physical appearance, self-esteem, and global physical self-concept is more susceptible to influences of socio-cultural factors in the monitored countries. In all other dimensions of Physical self-concept, sex differences were consistently manifested in favour of male adolescents, except in Flexibility. Regardless of adolescents' sex, under the increasing influence of Western culture in the Western Balkan countries, adolescents more critically evaluate their body and motor abilities.

  16. Pilot Study of Flow and Meaningfulness as Psychological Learning Concepts in Patient Education: A Short Report

    DEFF Research Database (Denmark)

    Nicic, Sara; Nørby, Karina; Bruun Johansen, Clea

    2014-01-01

    Abstract Background: The aim of this pilot study was to explore patient experiences of meaningfulness and flow related to group based patient education in type 2 diabetes. Meaningfulness and flow are underexposed as psychological learning concepts in patient education, and the ambition...... of this study was to investigate the applicability of these concepts of positive psychological theory in a patient education setting. Methods: This pilot study combines participating observation of group based patient education and 8 qualitative interviews with 4 patients with type 2 diabetes. Meaning...

  17. Possible Major Influences of Children Learning Social Studies on Academic Self Concept and Achievement

    Directory of Open Access Journals (Sweden)

    Laurens Kaluge

    2016-02-01

    Full Text Available This study was aimed at finding the best model to explain pupil academic attainment in learning social studies. The data came from pupils learning Social Studies at grade 3 and 4 of primary schools. The structural equation model contained 2 exogenous constructs–attitudes toward school and locus of control–and 2 endogenous constructs–self-concept and academic achievement. It was confirmed that the academic self-concept and achievement related to each other and both were influenced by attitudes toward school and internal locus of control. The model was fitting differently for different grade.

  18. Pilot Study of Flow and Meaningfulness as Psychological Learning Concepts in Patient Education: A Short Report

    DEFF Research Database (Denmark)

    Nicic, Sara; Nørby, Karina; Bruun Johansen, Clea;

    2014-01-01

    Abstract Background: The aim of this pilot study was to explore patient experiences of meaningfulness and flow related to group based patient education in type 2 diabetes. Meaningfulness and flow are underexposed as psychological learning concepts in patient education, and the ambition...... of this study was to investigate the applicability of these concepts of positive psychological theory in a patient education setting. Methods: This pilot study combines participating observation of group based patient education and 8 qualitative interviews with 4 patients with type 2 diabetes. Meaning...

  19. Erosion, Transportation, and Deposition on Outer Solar System Satellites: Landform Evolution Modeling Studies

    Science.gov (United States)

    Moore, Jeffrey Morgan; Howard, Alan D.; Schenk, Paul M.

    2013-01-01

    Mass movement and landform degradation reduces topographic relief by moving surface materials to a lower gravitational potential. In addition to the obvious role of gravity, abrasive mechanical erosion plays a role, often in combination with the lowering of cohesion, which allows disaggregation of the relief-forming material. The identification of specific landform types associated with mass movement and landform degradation provides information about local sediment particle size and abundance and transportation processes. Generally, mass movements can be classified in terms of the particle sizes of the transported material and the speed the material moved during transport. Most degradation on outer planet satellites appears consistent with sliding or slumping, impact erosion, and regolith evolution. Some satellites, such as Callisto and perhaps Hyperion and Iapetus, have an appearance that implies that some additional process is at work, most likely sublimation-driven landform modification and mass wasting. A variant on this process is thermally driven frost segregation as seen on all three icy Galilean satellites and perhaps elsewhere. Titan is unique among outer planet satellites in that Aeolian and fluvial processes also operate to erode, transport, and deposit material. We will evaluate the sequence and extent of various landform-modifying erosional and volatile redistribution processes that have shaped these icy satellites using a 3-D model that simulates the following surface and subsurface processes: 1) sublimation and re-condensation of volatiles; 2) development of refractory lag deposits; 3) disaggregation and downward sloughing of surficial material; 4) radiative heating/cooling of the surface (including reflection, emission, and shadowing by other surface elements); 5) thermal diffusion; and 6) vapor diffusion. The model will provide explicit simulations of landform development and thusly predicts the topographic and volatile evolution of the surface

  20. A comparative study of spherical and flat-Earth geopotential modeling at satellite elevations

    Science.gov (United States)

    Parrott, M. H.; Hinze, W. J.; Braile, L. W.

    1985-01-01

    Flat-Earth and spherical-Earth geopotential modeling of crustal anomaly sources at satellite elevations are compared by computing gravity and scalar magnetic anomalies perpendicular to the strike of variably dimensioned rectangular prisms at altitudes of 150, 300, and 450 km. Results indicate that the error caused by the flat-Earth approximation is less than 10% in most geometric conditions. Generally, error increase with larger and wider anomaly sources at higher altitudes. For most crustal source modeling applications at conventional satellite altitudes, flat-Earth modeling can be justified and is numerically efficient.

  1. Preserving self-concept in the burn survivors: A qualitative study

    Directory of Open Access Journals (Sweden)

    Vahid Zamanzadeh

    2015-01-01

    Full Text Available Background: Burn injury is a devastating experience affecting all aspects of a person′s essence, including his/her identity and perception. These patients require complex cognitive efforts to redefine their identity to deal with difficult condition after burn injury and preserve self-concept. The experience of life after burn injury is generally a solitary one, closely related to the patients′ cultural and religious context. Therefore, this study was conducted aiming at investigating burn patients′ experiences regarding how to preserve self-concept in life after burn injury in Iran. Materials and Methods: This qualitative study was carried out using qualitative content analysis and in-depth unstructured interviews with 17 surviving burn subjects. Results: During the qualitative content analysis process, the concept of "locating" as the essence of the participants′ experience was extracted as follows: (A self-exploration (exploring the changes in one′s life, (B others′ exploration (exploring the changes in the life of family members and the relationship between self and others, (C position evaluation (self-position analysis, and (D self-concept preservation. Conclusion: The present study has developed new understandings of mental experiences of burn patients′ self-concept by describing the concept of "self-locating." It helps us in classifying and understanding the concepts described in comprehensive theories developed in this area. They do this by focusing on what burn patients experience for choosing self-preservation strategies and having a meaningful life. The finding can be used as a conceptual framework for palliative care program in Iran.

  2. Comparative Study between Traditional and Heuristic Approach on Close-degree Concept Lattice for better Attribute Reduction

    Directory of Open Access Journals (Sweden)

    Mr. Ravindra k. Gupta

    2012-03-01

    Full Text Available Concept lattice is a new mathematical tool for data analysis and knowledge processing. There is an increasing interest on application of concept lattices in the different information systems. The concept lattice may be used for representation of the concept generalization structure generated from the underlying data set. Attribute reduction is very important in the theory of concept lattice because it can make the discovery of implicit knowledge in data easier and the representation simpler. The paper presents a modified lattice building algorithm where the generated concept nodes may contain not only the attributes of the children nodes but some other generalized attributes, too. The generalization structure of the attributes is called attribute lattice. In this approach we find concept lattice, Attribute Concept lattice and, Formal Concept Lattice based on all the deduction we find the Heuristic Result which provide better attribute reduction. We also discuss a comparative study between the traditional and the new heuristic approach.

  3. Concept Learning in the Undergraduate Classroom: A Case Study in Religious Studies

    Science.gov (United States)

    Jones, Jennifer L.; St. Hilaire, Robert

    2014-01-01

    Popularized by the work of Jerome Bruner in the mid-1990's, the "Concept Attainment Model" is a process of structured inquiry that requires students to make generalizations and draw conclusions from examples (and non-examples) of a particular concept toward developing new insights, hypotheses, and associations regarding what they have…

  4. Effects of concept map teaching on students' critical thinking and approach to learning and studying.

    Science.gov (United States)

    Chen, Shiah-Lian; Liang, Tienli; Lee, Mei-Li; Liao, I-Chen

    2011-08-01

    The purpose of this study was to explore the effects of concept mapping in developing critical thinking ability and approach to learning and studying. A quasi-experimental study design with a purposive sample was drawn from a group of nursing students enrolled in a medical-surgical nursing course in central Taiwan. Students in the experimental group were taught to use concept mapping in their learning. Students in the control group were taught by means of traditional lectures. After the intervention, the experimental group had better overall critical thinking scores than did the control group, although the difference was not statistically significant. After controlling for the effects of age and the pretest score on critical thinking using analysis of covariance, the experimental group had significantly higher adjusted mean scores on inference and overall critical thinking compared with the control group. Concept mapping is an effective tool for improving students' ability to think critically.

  5. Social phobia and self-concept: a correlational study with physical activity practice

    Directory of Open Access Journals (Sweden)

    Christi Noriko Sonoo

    2008-12-01

    Full Text Available The objective of this study was to analyze social phobia in teenagers aged 14 to 20 years and its possiblerelationship with regular practice of physical activity and their self-concept. This study enrolled 191 students from privateand public schools and the measurement instruments used were a test of social phobia, a test of self-concept and a physicalactivity questionnaire. The results indicate that students from private schools are shyer than students from public schools. Inrelation to self-concept, there were significant differences in security factor for boys and moral factor for girls. This indicatesthat boys are more stable, brave and secure, while girls are more influenced by moral and ethical rules. These resultsdemonstrate that no relationship was detected between social phobia and physical activity, but it was possible to observea relationship between social phobia and some of the self-concept factors, and a relationship between physical activityand some of the self-concept factors. It is therefore concluded that the negative influence of high levels of social phobia onthe receptivity and security factors of men and women suggests a need for further studies in the area, which could help inthe prevention and treatment of social phobia, which could worsen over the years and compromise these young people’sability to socialize.

  6. Study of time-lapse processing for dynamic hydrologic conditions. [electronic satellite image analysis console for Earth Resources Technology Satellites imagery

    Science.gov (United States)

    Serebreny, S. M.; Evans, W. E.; Wiegman, E. J.

    1974-01-01

    The usefulness of dynamic display techniques in exploiting the repetitive nature of ERTS imagery was investigated. A specially designed Electronic Satellite Image Analysis Console (ESIAC) was developed and employed to process data for seven ERTS principal investigators studying dynamic hydrological conditions for diverse applications. These applications include measurement of snowfield extent and sediment plumes from estuary discharge, Playa Lake inventory, and monitoring of phreatophyte and other vegetation changes. The ESIAC provides facilities for storing registered image sequences in a magnetic video disc memory for subsequent recall, enhancement, and animated display in monochrome or color. The most unique feature of the system is the capability to time lapse the imagery and analytic displays of the imagery. Data products included quantitative measurements of distances and areas, binary thematic maps based on monospectral or multispectral decisions, radiance profiles, and movie loops. Applications of animation for uses other than creating time-lapse sequences are identified. Input to the ESIAC can be either digital or via photographic transparencies.

  7. Are Alternative Conceptions Dependent on Researchers' Methodology and Definition?: A Review of Empirical Studies Related to Concepts of Heat

    Science.gov (United States)

    Wong, Chee Leong; Chu, Hye-Eun; Yap, Kueh Chin

    2016-01-01

    Currently, there is no agreement among scientists and science educators on whether heat should be defined as a "process of energy transfer" or "form of energy." For example, students may conceive of heat as "molecular kinetic energy," but the interpretation of this alternative conception is dependent on educational…

  8. The Effect of Compensation Studies on Disadvantaged Children's Self Concept Levels and Locus of Control

    Science.gov (United States)

    Sadioglu, Ömür

    2017-01-01

    The aim of this study is to determine the effect of "Bir Umut Ol Benim Için" (Be My Hope) project which was prepared for the children who were disadvantaged by being influenced from several risk factors as compared to their peers on the self-concepts and locus of controls of the children. The study group consisted of 33 children who were…

  9. A review of structurally inspired approaches in housing studies: Concepts, contributions and future perspectives

    NARCIS (Netherlands)

    Lawson, J.M.

    2009-01-01

    Housing studies is a broad field, which has ploughed the disciplines of political economy, radical geography and sociology since the 1970s, making use of structural theories, concepts and methods. These studies have embroidered notions of human agency engaged in different aspects of housing provisio

  10. A Study of Taiwanese Children's Conceptions of and Relation to Nature: Curricular and Policy Implications

    Science.gov (United States)

    Dai, Amy Hsin-I

    2011-01-01

    The present study investigated children's conceptions of and relations to nature. Understanding the factors that influence them was the goal. The study used the Contextual Model of Learning as the theoretical framework to structure the research questions and data analysis to understand children's nature learning in the personal, sociocultural, and…

  11. Students' Conceptions of the Second Law of Thermodynamics--An Interpretive Study.

    Science.gov (United States)

    Kesidou, Sofia; Duit, Reinders

    1993-01-01

    Interviews were conducted with grade 10 students (n=34) who had received 4 years of physics instruction. Interview's focus was to understand students' responses from their point of view. The results of the study confirm and deepen findings from other studies concerning students' severe difficulties in learning the energy concept, the particle…

  12. A Phenomenographic Study of Lecturers' Conceptions of Using Learning Technology in a Pakistani Context

    Science.gov (United States)

    Hodgson, Vivien; Shah, Uzair

    2017-01-01

    While there are many studies exploring the phenomenon of lecturers' use of learning technology within teaching practices in western higher education contexts, currently we know little about this phenomenon within less developed countries. In the paper, we discuss the findings from a phenomenographic study of lecturers' conceptions of using…

  13. Reflections on Teaching Periodic Table Concepts: A Case Study of Selected Schools in South Africa

    Science.gov (United States)

    Mokiwa, Hamza Omari

    2017-01-01

    The Periodic Table of Elements is central to the study of modern Physics and Chemistry. It is however, considered by teachers as difficult to teach. This paper reports on a case study exploring reflections on teaching periodic table concepts in five secondary schools from South Africa. Qualitative methodology of interviews and document analysis…

  14. A Cross-Age Study of an Understanding of Light and Sight Concepts in Physics

    Science.gov (United States)

    Uzun, Salih; Alev, Nedim; Karal, Isik Saliha

    2013-01-01

    The aim of this study is to reveal the students' and pre-service teachers' understanding of light, sight and related concepts at different educational levels, from primary to higher education. A cross-sectional approach was used since the participants were of different age and educational level. The sample of this study consisted of 30 eighth…

  15. Reducing antimicrobial therapy for asymptomatic bacteriuria among noncatheterized inpatients: a proof-of-concept study.

    Science.gov (United States)

    Leis, Jerome A; Rebick, Gabriel W; Daneman, Nick; Gold, Wayne L; Poutanen, Susan M; Lo, Pauline; Larocque, Michael; Shojania, Kaveh G; McGeer, Allison

    2014-04-01

    This proof-of-concept study demonstrates that no longer routinely reporting urine culture results from noncatheterized medical and surgical inpatients can greatly reduce unnecessary antimicrobial therapy for asymptomatic bacteriuria without significant additional laboratory workload. Larger studies are needed to confirm the generalizability, safety, and sustainability of this model of care.

  16. The Influence of Arthur A. Schomburg on My Concept of Africana Studies.

    Science.gov (United States)

    Clarke, John Henrik

    1992-01-01

    Discusses the influence of Arthur A. Schomburg on the present author's concept of African studies and his knowledge of African history. Schomburg is presented as the antecedent of the Black Studies Revolution and one of the ideological fathers of this generation of scholars. (SLD)

  17. A Case Study in Master Planning the Learning Landscape Hub Concepts for the University at Buffalo

    Science.gov (United States)

    Dugdale, Shirley; Torino, Roger; Felix, Elliot

    2009-01-01

    This case study describes concepts for three types of learning spaces that grew out of a Learning Landscape planning process. The process was part of a master plan study for the three campuses of the University at Buffalo. It involved research into user needs and aspirations about future pedagogy, development of learning space strategy,…

  18. Gaps in EU Foreign Policy: the Role of Concepts in European Studies

    DEFF Research Database (Denmark)

    Larsen, Henrik

    of Capability-Expectations Gap in the study of European foreign policy. Through examples from the literature, it is shown that the concept sets up standards for the EU as a foreign policy actor that are not met by most other international actors and that this curtails analysis of EU foreign policy....... It then demonstrates that the widespread use of the concept of ‘gap’ in different forms affects the way in which EU foreign policy has been studied and that it always produces the same result: the EU is an unfulfilled actor outside the realm of “normal” actors in IR....

  19. Pre-service teachers’ conceptions on use of social media in social studies education

    OpenAIRE

    Kahveci, Nihat Gürel

    2015-01-01

    The use of social media is tremendously increasing trend for personal use. At the same time, social media are penetrating to the educational settings as well. Thus purpose of this study is to investigate pre-service social studies teachers’ conceptions on use of social media in social studies education; it is possible implications on social studies teacher education, social studies classroom and consequently citizenship education. Data were collected through open- ended interviews with 12 (6 ...

  20. Customer premise service study for 30/20 GHz satellite system

    Science.gov (United States)

    Milton, R. T.; Ross, D. P.; Harcar, A. R.; Freedenberg, P.; Schoen, D.

    1983-01-01

    Satellite systems in which the space segment operates in the 30/20 GHz frequency band are defined and compared as to their potential for providing various types of communications services to customer premises and the economic and technical feasibility of doing so. Technical tasks performed include: market postulation, definition of the ground segment, definition of the space segment, definition of the integrated satellite system, service costs for satellite systems, sensitivity analysis, and critical technology. Based on an analysis of market data, a sufficiently large market for services is projected so as to make the system economically viable. A large market, and hence a high capacity satellite system, is found to be necessary to minimize service costs, i.e., economy of scale is found to hold. The wide bandwidth expected to be available in the 30/20 GHz band, along with frequency reuse which further increases the effective system bandwidth, makes possible the high capacity system. Extensive ground networking is required in most systems to both connect users into the system and to interconnect Earth stations to provide spatial diversity. Earth station spatial diversity is found to be a cost effective means of compensating the large fading encountered in the 30/20 GHz operating band.

  1. Satellite Altimetry and GRACE Gravimetry for Studies of Annual Water Storage Variations in Bangladesh

    Directory of Open Access Journals (Sweden)

    Ole Andersen

    2008-01-01

    Full Text Available Four different data sources have been compared with respect to observations of the annual water storage variations in the region of Bangladesh. Data from satellite altimeters and river gauges estimates the variation in surface water storage in the major rivers of Bangladesh.

  2. Simultaneous optical and satellite observations of auroras in the mantle: Case study

    Science.gov (United States)

    Safargaleev, V. V.; Mitrofanov, V. M.; Roldugin, A. V.

    2016-11-01

    The all-sky camera data obtained in Barentsburg (Spitsbergen Archipelago) are compared with specific features of electron and ion precipitations on the DMSP F18 satellite during its flight within the camera field of view on December 15, 2012. Before arriving at the cusp from the mantle side, the satellite detects two outbursts of precipitating particles. The burst of mantle precipitations far from the cusp is observed simultaneously in both ionic and electronic components. In the ionosphere related to the satellite, no auroras are detected, which is likely due to the low intensity of the flux of precipitating electrons and their low energy (80 eV). Near the cusp, a more intensive burst of precipitations of higher-energy electrons (140 eV) is accompanied by an almost complete "locking" of ions. This burst of mantle precipitations is related to the faint luminous structure in the ionosphere. The ion locking is indicative of the accelerating potential difference in the force tube, which is based on the glowing region. The luminous structure is an element of the so-called "polewar moving auroral forms," which is related in the literature to the reconnection in the daytime magnetopause. The possible relation of the observed phenomena to the reconnected magnetic force tubes, which drift from the cusp in the antisolar direction, is also confirmed by the dispersion of ionic precipitations, i.e., an increase in ion energy as the satellite approaches to the cusp.

  3. NanoSAR – Case study of synthetic aperture radar for nano-satellites

    NARCIS (Netherlands)

    Engelen, S.; Oever, M. van den; Mahapatra, P.S.; Sundaramoorthy, P.P.; Gill, E.K.A.; Meijer, R.J.; Verhoeven, C.J.M.

    2012-01-01

    Nano-satellites have a cost advantage due to their low mass and usage of commercial-off-the-shelf technologies. However, the low mass also restricts the functionality of a nano-satellite’s payload. Typically, this would imply instruments with very low to low resolution and accuracy, essentially

  4. Conjunction of tail satellites for substorm study: ISTP event of 1997 January 2

    DEFF Research Database (Denmark)

    Lui, A.T.Y.; Liou, K.; Newell, P.T.;

    2000-01-01

    dipolarization at Geotail and highly fluctuating magnetic field (mostly northward B-z) at IMP-8. Observations for this substorm showed no indication of mid-tail activities occurring prior to auroral brightening for both onset and intensification even though the satellites observed activities subsequently. Close...

  5. Initializing HYSPLIT with satellite observations of volcanic ash: A case study of the 2008 Kasatochi eruption

    Science.gov (United States)

    Crawford, Alice M.; Stunder, Barbara J. B.; Ngan, Fong; Pavolonis, Michael J.

    2016-09-01

    The current work focuses on improving volcanic ash forecasts by integrating satellite observations of ash into the Lagrangian transport and dispersion model, HYSPLIT. The accuracy of HYSPLIT output is dependent on the accuracy of the initialization: the initial position, size distribution, and amount of ash as a function of time. Satellite observations from passive infrared, IR, sensors are used both to construct the initialization term and for verification. Space-based lidar observations are used for further verification. We compare model output produced using different initializations for the 2008 eruption of Kasatochi in the Aleutian Islands. Simple source terms, such as a uniform vertical line or cylindrical source above the vent, are compared to initializations derived from satellite measurements of position, mass loading, effective radius, and height of the downwind ash cloud. Using satellite measurements of column mass loading of ash to constrain the source term produces better long-term predictions than using an empirical equation relating mass eruption rate and plume height above the vent. Even though some quantities, such as the cloud thickness, must be estimated, initializations which release particles at the position of the observed ash cloud produce model output which is comparable to or better than the model output produced with source terms located above and around the vent. Space-based lidar data, passive IR retrievals of ash cloud top height, and model output agree well with each other, and all suggest that the Kasatochi ash cloud evolved into a complex three-dimensional structure.

  6. Study on networking issues of medium earth orbit satellite communications systems

    Science.gov (United States)

    Araki, Noriyuki; Shinonaga, Hideyuki; Ito, Yasuhiko

    1993-01-01

    Two networking issues of communications systems with medium earth orbit (MEO) satellites, namely network architectures and location determination and registration methods for hand-held terminals, are investigated in this paper. For network architecture, five candidate architectures are considered and evaluated in terms of signaling traffic. For location determination and registration, two methods are discussed and evaluated.

  7. Fractional calculus approach to study temperature distribution within a spinning satellite

    Directory of Open Access Journals (Sweden)

    Jyotindra C. Prajapati

    2016-09-01

    Full Text Available This paper deals with the temperature distribution within spinning satellites and problem is formulated in terms of fractional differential equation. Applying fractional calculus approach, solution of this equation is obtained in terms of Wright generalized hypergeometric function, a generalization of exponential function.

  8. Advanced EVA Capabilities: A Study for NASA's Revolutionary Aerospace Systems Concept Program

    Science.gov (United States)

    Hoffman, Stephen J.

    2004-01-01

    This report documents the results of a study carried out as part of NASA s Revolutionary Aerospace Systems Concepts Program examining the future technology needs of extravehicular activities (EVAs). The intent of this study is to produce a comprehensive report that identifies various design concepts for human-related advanced EVA systems necessary to achieve the goals of supporting future space exploration and development customers in free space and on planetary surfaces for space missions in the post-2020 timeframe. The design concepts studied and evaluated are not limited to anthropomorphic space suits, but include a wide range of human-enhancing EVA technologies as well as consideration of coordination and integration with advanced robotics. The goal of the study effort is to establish a baseline technology "road map" that identifies and describes an investment and technical development strategy, including recommendations that will lead to future enhanced synergistic human/robot EVA operations. The eventual use of this study effort is to focus evolving performance capabilities of various EVA system elements toward the goal of providing high performance human operational capabilities for a multitude of future space applications and destinations. The data collected for this study indicate a rich and diverse history of systems that have been developed to perform a variety of EVA tasks, indicating what is possible. However, the data gathered for this study also indicate a paucity of new concepts and technologies for advanced EVA missions - at least any that researchers are willing to discuss in this type of forum.

  9. A DEEP STUDY OF THE DWARF SATELLITES ANDROMEDA XXVIII AND ANDROMEDA XXIX

    Energy Technology Data Exchange (ETDEWEB)

    Slater, Colin T.; Bell, Eric F. [Department of Astronomy, University of Michigan, 1085 S. University Ave., Ann Arbor, MI 48109 (United States); Martin, Nicolas F. [Observatoire astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, 11 rue de l’Université, F-67000 Strasbourg (France); Tollerud, Erik J.; Ho, Nhung [Astronomy Department, Yale University, P.O. Box 208101, New Haven, CT 06510 (United States)

    2015-06-20

    We present the results of a deep study of the isolated dwarf galaxies Andromeda XXVIII and Andromeda XXIX with Gemini/GMOS and Keck/DEIMOS. Both galaxies are shown to host old, metal-poor stellar populations with no detectable recent star formation, conclusively identifying both of them as dwarf spheroidal galaxies (dSphs). And XXVIII exhibits a complex horizontal branch morphology, which is suggestive of metallicity enrichment and thus an extended period of star formation in the past. Decomposing the horizontal branch into blue (metal-poor, assumed to be older) and red (relatively more metal-rich, assumed to be younger) populations shows that the metal-rich are also more spatially concentrated in the center of the galaxy. We use spectroscopic measurements of the calcium triplet, combined with the improved precision of the Gemini photometry, to measure the metallicity of the galaxies, confirming the metallicity spread and showing that they both lie on the luminosity–metallicity relation for dwarf satellites. Taken together, the galaxies exhibit largely typical properties for dSphs despite their significant distances from M31. These dwarfs thus place particularly significant constraints on models of dSph formation involving environmental processes such as tidal or ram pressure stripping. Such models must be able to completely transform the two galaxies into dSphs in no more than two pericentric passages around M31, while maintaining a significant stellar population gradient. Reproducing these features is a prime requirement for models of dSph formation to demonstrate not just the plausibility of environmental transformation but the capability of accurately recreating real dSphs.

  10. Photometric and spectroscopic study of the ultra-faint Milky Way satellite Pegasus III

    Science.gov (United States)

    Kim, Dongwon; Jerjen, Helmut; Geha, Marla C.; Chiti, Anirudh; Milone, Antonino; Da Costa, Gary S.; Mackey, Dougal; Frebel, Anna; Conn, Blair

    2017-01-01

    Pegasus III (Peg III) is one of the few known ultra-faint dwarf (UFD) satellite galaxies in the outer halo (R >150 kpc) of the Milky Way (MW). We present results from a recent study of Peg III using Magellan/IMACS and Keck/DEIMOS. Our newly-measured structural parameters confirm that Peg III is large (rh = 53±14pc), elongated (∈ = 0.38+0.22-0.38 ), and faint (MV=-3.4±0.4 mag) — indicative of its nature as a dwarf rather than a globular cluster. In the color-magnitude diagram, Peg III is well described by an old (>12Gyr) and metal-poor ([Fe/H]measurements of individual stars, we identify seven kinematic members of Peg III. The Ca II triplet lines of the brightest members verify that Peg III indeed contains stars with metallicity as low as [Fe/H]=-2.55±0.15 dex. The systemic velocity and velocity dispersion of Peg III are -222.9±2.6 km/s and 5.4+3.0-2.5 km/s, respectively. The inferred dynamical mass within the half-light radius of 1.4+3.0-1.1×106M⊙, and the mass-to-light ratio of M/LV = 1470+5660-1240M⊙/L⊙ provide further evidence that Peg III is a bona fide UFD. Peg III and another distant UFD Pisces II lie relatively close to each other (△dspatial=43±19 kpc) and share similar systemic radial velocities (△vGSR=12.3±3.7 km/s), which suggests that they may share a common origin.

  11. A Deep Study of the Dwarf Satellites Andromeda XXVIII and Andromeda XXIX

    Science.gov (United States)

    Slater, Colin T.; Bell, Eric F.; Martin, Nicolas F.; Tollerud, Erik J.; Ho, Nhung

    2015-06-01

    We present the results of a deep study of the isolated dwarf galaxies Andromeda XXVIII and Andromeda XXIX with Gemini/GMOS and Keck/DEIMOS. Both galaxies are shown to host old, metal-poor stellar populations with no detectable recent star formation, conclusively identifying both of them as dwarf spheroidal galaxies (dSphs). And XXVIII exhibits a complex horizontal branch morphology, which is suggestive of metallicity enrichment and thus an extended period of star formation in the past. Decomposing the horizontal branch into blue (metal-poor, assumed to be older) and red (relatively more metal-rich, assumed to be younger) populations shows that the metal-rich are also more spatially concentrated in the center of the galaxy. We use spectroscopic measurements of the calcium triplet, combined with the improved precision of the Gemini photometry, to measure the metallicity of the galaxies, confirming the metallicity spread and showing that they both lie on the luminosity-metallicity relation for dwarf satellites. Taken together, the galaxies exhibit largely typical properties for dSphs despite their significant distances from M31. These dwarfs thus place particularly significant constraints on models of dSph formation involving environmental processes such as tidal or ram pressure stripping. Such models must be able to completely transform the two galaxies into dSphs in no more than two pericentric passages around M31, while maintaining a significant stellar population gradient. Reproducing these features is a prime requirement for models of dSph formation to demonstrate not just the plausibility of environmental transformation but the capability of accurately recreating real dSphs.

  12. Status and path forward for the large ultraviolet/optical/infrared surveyor (LUVOIR) mission concept study

    Science.gov (United States)

    Crooke, Julie A.; Roberge, Aki; Domagal-Goldman, Shawn D.; Mandell, Avi M.; Bolcar, Matthew R.; Rioux, Norman M.; Perez, Mario R.; Smith, Erin C.

    2016-07-01

    In preparation of the 2020 Astrophysics Decadal Survey, National Aeronautics and Space Administration (NASA) has commenced a process for the astronomical community to study several large mission concepts leveraging the lessons learned from past Decadal Surveys. This will enable the Decadal Survey committee to make more informed recommendations to NASA on its astrophysics science and mission priorities with respect to cost and risk. Four astrophysics large mission concepts were identified. Each of them had a Science and Technology Definition Teem (STDT) chartered to produce scientifically compelling, feasible, and executable design reference mission (DRM) concepts to present to the 2020 Decadal Survey. In addition, The Aerospace Corporation will perform an independent cost and technical evaluation (CATE) of each of these mission concept studies in advance of the 2020 Decadal Survey, by interacting with the STDTs to provide detailed technical details on certain areas for which "deep dives" are appropriate. This paper presents the status and path forward for one of the four large mission concepts, namely, the Large UltraViolet, Optical, InfraRed surveyor (LUVOIR).

  13. 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.

  14. A Study to Determine the Contribution Made by Concept Maps to a Computer Architecture and Organization Course

    Science.gov (United States)

    Aydogan, Tuncay; Ergun, Serap

    2016-01-01

    Concept mapping is a method of graphical learning that can be beneficial as a study method for concept linking and organization. Concept maps, which provide an elegant, easily understood representation of an expert's domain knowledge, are tools for organizing and representing knowledge. These tools have been used in educational environments to…

  15. A study of possible sea state information in the sample and hold gate statistics for the GEOS-3 satellite altimeter

    Science.gov (United States)

    Wells, W. T.; Borman, K. L.; Mitchell, R. D.; Dempsey, D. J.

    1979-01-01

    The statistical variations in the sample gate outputs of the GEOS-3 satellite altimeter were studied for possible sea state information. After examination of a large number of statistical characteristics of the altimeter waveforms, it was found that the best sea predictor for H-1/3 in the range of 0 to 3 meters was the 75th percentile of sample and hold gate number 11.

  16. Concept study for the next generation medium-energy gamma-ray astronomy mission: MEGA

    Science.gov (United States)

    Kanbach, Gottfried; Andritschke, Robert; Bloser, Peter F.; Schopper, Florian; Schoenfelder, Volker; Zoglauer, Andreas

    2003-03-01

    A new telescope for Medium Energy Gamma-Ray Astronomy, MEGA, is being developed for the energy band 0.4 - 50 MeV as a successor to COMPTEL on CGRO. MEGA aims to improve the sensitivity for astronomical sources by at least an order of magnitude with respect to past instruments and will fill a severe sensitivity gap between already scheduled hard-X-ray and high-energy gamma-ray missions. MEGA records and images gamma rays by completely tracking Compton and pair creation events in a stack of double sided Si-strip track detectors surrounded by a pixelated CsI calorimeter. MEGA will have an effective area of ~100 square cm, a large field of view of ~130 degrees, angular resolution of ~2 degrees, and energy resolution of ~8% (all FWHM at ~2 MeV). Key science objectives for MEGA are the investigation of cosmic high-energy accelerators, nucleosynthesis sites with gamma-ray lines, and the mapping of large-scale structures in the Galaxy and beyond. If operated on a zenith pointing satellite MEGA will be an ideal continuous all-sky monitor for transient sources. This paper describes the development of a small scale prototype and the concept of a space mission for MEGA.

  17. Academic self-concept, academic achievement, and leadership in university students studying in a physical therapy program.

    Science.gov (United States)

    Gottlieb, Rosemary J; Rogers, Janet L

    2002-01-01

    Students enrolled in a selected admissions program, in which there are a limited number of student positions available, were assessed for academic self-concept using the Dimensions of Self-Concept upon entry into the program. This study was performed to explore whether academic self-concept scores could predict successful completion of an academic program and the impact of self-concept scores on academic achievement and professional leadership.

  18. 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.

  19. New concepts for the comparison of tropospheric NO2 column densities derived from car-MAX-DOAS observations, OMI satellite observations and the regional model CHIMERE during two MEGAPOLI campaigns in Paris 2009/10

    Directory of Open Access Journals (Sweden)

    R. Shaiganfar

    2015-03-01

    Full Text Available We compare tropospheric column densities (vertically integrated concentrations of NO2 from three data sets for the metropolitan area of Paris during two extensive measurement campaigns (25 days in summer 2009 and 29 days in winter 2010 within the European research project MEGAPOLI. The selected data sets comprise a regional chemical transport model (CHIMERE as well as two observational data sets: ground based mobile Multi-AXis-Differential Optical Absorption Spectroscopy (car-MAX-DOAS measurements and satellite measurements from the Ozone Monitoring Instrument (OMI. On most days, car-MAX-DOAS measurements were carried out along large circles (diameter ~35 km around Paris. The car-MAX-DOAS results are compared to coincident data from CHIMERE and OMI. All three data sets have their specific strengths and weaknesses, especially with respect to their spatio-temporal resolution and coverage as well as their uncertainties. Thus we compare them in two different ways: first, we simply consider the original data sets. Second, we compare modified versions making synergistic use of the complementary information from different data sets. For example, profile information from the regional model is used to improve the satellite data, observations of the horizontal trace gas distribution are used to adjust the respective spatial patterns of the model simulations, or the model is used as a transfer tool to bridge the spatial scales between car-MAX-DOAS and satellite observations. Using the modified versions of the data sets, the comparison results substantially improve compared to the original versions. In general, good agreement between the data sets is found outside the emission plume, but inside the emission plumes the tropospheric NO2 VCDs are systematically underestimated by the CHIMERE model and the satellite observations (compared to the car-MAX-DOAS observations. One major result from our study is that for satellite validation close to strong emission

  20. A comparative study on undergraduate students' academic motivation and academic self-concept.

    Science.gov (United States)

    Isiksal, Mine

    2010-11-01

    The purpose of this study was to investigate Turkish and American undergraduate students' academic motivation and academic self-concept scores regarding the years that they spent in university. The analysis was based on 566 (284 Turkish, 282 American) undergraduate students where, Academic Motivation Scale and Academic Self-Concept Scale were used as measuring instruments. The results showed that there was a statistical significant effect of nationality and number of years spent in university on undergraduate students' intrinsic motivation, extrinsic motivation, and self-concept scores. Turkish students had higher intrinsic scores whereas American students had higher extrinsic scores and more positive academic-self concept compared to Turkish partners. Regarding grade level, senior students from both cultures had higher intrinsic motivation and academic self-concept scores compared to other grade levels. In terms of extrinsic motivation, there is steady decline in American students' scores as grade level increases. On the other hand, Turkish undergraduates' extrinsic scores decrease in the second year but increase in the third and fourth year of university education. Results were discussed by taking into consideration the social and cultural differences between two nations.

  1. Market Potential Study for Standing Cabin Concept for Domestic Low-Cost Commercial Airlines in Malaysia

    Science.gov (United States)

    Romli, Fairuz I.; Dasuki, Norhafizah; Yazdi Harmin, Mohammad

    2016-02-01

    An affordable air transportation has become the operational aim of many airlines these days. This is to cater the growing air travel demands from people of different social and economic status. One of the revolutionary proposals to reduce the operational costs, hence the flight ticket price, is by introducing the so-called standing cabin concept. This concept involves transporting passengers during the entire flight in their standing position with a proper support of a vertical seat. As can be expected with many new inventions, despite its clear advantages, the concept has been met with mixed reactions from the public. This study intends to establish whether the standing cabin concept has a market potential to be implemented for domestic flights in Malaysia. The public perception is determined from collected data through a survey done at two major local low-cost airport terminals. It can be concluded from the results that the concept has a good market potential for application on flights with duration of less than two hours.

  2. Design optimization studies for large-scale contoured beam deployable satellite antennas

    Science.gov (United States)

    Tanaka, Hiroaki

    2006-05-01

    Satellite communications systems over the past two decades have become more sophisticated and evolved new applications that require much higher flux densities. These new requirements to provide high data rate services to very small user terminals have in turn led to the need for large aperture space antenna systems with higher gain. Conventional parabolic reflectors constructed of metal have become, over time, too massive to support these new missions in a cost effective manner and also have posed problems of fitting within the constrained volume of launch vehicles. Designers of new space antenna systems have thus begun to explore new design options. These design options for advanced space communications networks include such alternatives as inflatable antennas using polyimide materials, antennas constructed of piezo-electric materials, phased array antenna systems (especially in the EHF bands) and deployable antenna systems constructed of wire mesh or cabling systems. This article updates studies being conducted in Japan of such deployable space antenna systems [H. Tanaka, M.C. Natori, Shape control of space antennas consisting of cable networks, Acta Astronautica 55 (2004) 519-527]. In particular, this study shows how the design of such large-scale deployable antenna systems can be optimized based on various factors including the frequency bands to be employed with such innovative reflector design. In particular, this study investigates how contoured beam space antennas can be effective by constructed out of so-called cable networks or mesh-like reflectors. This design can be accomplished via "plane wave synthesis" and by the "force density method" and then to iterate the design to achieve the optimum solution. We have concluded that the best design is achieved by plane wave synthesis. Further, we demonstrate that the nodes on the reflector are best determined by a pseudo-inverse calculation of the matrix that can be interpolated so as to achieve the minimum

  3. Concepts of person-centred care: a framework analysis of five studies in daily care practices

    Directory of Open Access Journals (Sweden)

    Margreet

    2016-11-01

    Full Text Available Background: Person-centred care is used as a term to indicate a ‘made to measure’ approach in care. But what does this look like in daily practice? The person-centred nursing framework developed by McCormack and McCance (2010 offers specific concepts but these are still described in rather general terms. Empirical studies, therefore, could help to clarify them and make person-centredness more tangible for nurses. Aims: This paper describes how a framework analysis aimed to clarify the concepts described in the model of McCormack and McCance in order to guide professionals using them in practice. Methods: Five separate empirical studies focusing on older adults in the Netherlands were used in the framework analysis. The research question was: ‘How are concepts of person-centred care made tangible where empirical data are used to describe them?’ Analysis was done in five steps, leading to a comparison between the description of the concepts and the empirical significance found in the studies. Findings: Suitable illustrations were found for the majority of concepts. The results show that an empirically derived specification emerges from the data. In the concept of ‘caring relationship’ for example, it is shown that the personal character of each relationship is expressed by what the nurse and the older person know about each other. Other findings show the importance of values being present in care practices. Conclusions: The framework analysis shows that concepts can be clarified when empirical studies are used to make person-centred care tangible so nurses can understand and apply it in practice. Implications for practice: The concepts of the person-centred nursing framework are recognised when: Nurses know unique characteristics of the person they care for and what is important to them, and act accordingly Nurses use values such as trust, involvement and humour in their care practice Acknowledgement of emotions and compassion create

  4. Space-Based Gravitational-Wave Observatory (SGO) Mission Concept Study

    Science.gov (United States)

    Livas, Jeffrey; McNamara, Paul; Jennrich, Oliver

    2012-01-01

    The LISA Mission Concept has been under study for over two decades as a space-based gravitational-wave detector capable of observing astrophysical sources in the 0.0001 to 1 Hz band. The concept has consistently received strong recommendations from various review panels based on the expected science, most recently from the US Astr02010 Decadal Review. Budget constraints have led both the US and European Space agencies to search for lower cost options. We report results from the US effort to explore the tradeoffs between mission cost and science return.

  5. Studies of Credit and Equity Markets with Concepts of Theoretical Physics

    CERN Document Server

    Münnix, Michael C

    2011-01-01

    Financial markets are becoming increasingly complex. The financial crisis of 2008 to 2009 has demonstrated that an improved understanding of the mechanisms embedded in the market is a key requirement for the estimation of financial risk. Recently, concepts of theoretical physics, in particular concepts of complex systems, have proven to be very useful in this regard. Michael C. Münnix analyses the statistical dependencies in financial markets and develops mathematical models using concepts and methods from physics. The author focuses on aspects that played a key role in the emergence of the recent financial crisis: estimation of credit risk, dynamics of statistical dependencies, and correlations on small time-scales. He visualizes the findings for various large-scale empirical studies of market data. The results give novel insights into the mechanisms of financial markets and allow conclusions on how to reduce financial risk significantly.

  6. Using Enabling Technologies to Facilitate the Comparison of Satellite Observations with the Model Forecasts for Hurricane Study

    Science.gov (United States)

    Li, P.; Knosp, B.; Hristova-Veleva, S. M.; Niamsuwan, N.; Johnson, M. P.; Shen, T. P. J.; Tanelli, S.; Turk, J.; Vu, Q. A.

    2014-12-01

    Due to their complexity and volume, the satellite data are underutilized in today's hurricane research and operations. To better utilize these data, we developed the JPL Tropical Cyclone Information System (TCIS) - an Interactive Data Portal providing fusion between Near-Real-Time satellite observations and model forecasts to facilitate model evaluation and improvement. We have collected satellite observations and model forecasts in the Atlantic Basin and the East Pacific for the hurricane seasons since 2010 and supported the NASA Airborne Campaigns for Hurricane Study such as the Genesis and Rapid Intensification Processes (GRIP) in 2010 and the Hurricane and Severe Storm Sentinel (HS3) from 2012 to 2014. To enable the direct inter-comparisons of the satellite observations and the model forecasts, the TCIS was integrated with the NASA Earth Observing System Simulator Suite (NEOS3) to produce synthetic observations (e.g. simulated passive microwave brightness temperatures) from a number of operational hurricane forecast models (HWRF and GFS). An automated process was developed to trigger NEOS3 simulations via web services given the location and time of satellite observations, monitor the progress of the NEOS3 simulations, display the synthetic observation and ingest them into the TCIS database when they are done. In addition, three analysis tools, the joint PDF analysis of the brightness temperatures, ARCHER for finding the storm-center and the storm organization and the Wave Number Analysis tool for storm asymmetry and morphology analysis were integrated into TCIS to provide statistical and structural analysis on both observed and synthetic data. Interactive tools were built in the TCIS visualization system to allow the spatial and temporal selections of the datasets, the invocation of the tools with user specified parameters, and the display and the delivery of the results. In this presentation, we will describe the key enabling technologies behind the design of

  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. Prospects of Source-Separation-Based Sanitation Concepts: A Model-Based Study

    NARCIS (Netherlands)

    Tervahauta, T.H.; Trang Hoang,; Hernández, L.; Zeeman, G.; Buisman, C.J.N.

    2013-01-01

    Separation of different domestic wastewater streams and targeted on-site treatment for resource recovery has been recognized as one of the most promising sanitation concepts to re-establish the balance in carbon, nutrient and water cycles. In this study a model was developed based on literature data

  9. Using Concept Maps to Elicit and Study Student Teachers' Perceptions about Inclusive Education: A Tanzanian Experience

    Science.gov (United States)

    Wormnaes, Siri; Mkumbo, Kitila; Skaar, Bjørn; Refseth, Yngve

    2015-01-01

    In this study, concept map activities were used to trigger group discussions about inclusive education, with a focus on learners with disabilities. The participants were 226 Tanzanian student teachers. This article reports and discusses how the maps were analysed and what they indicate about the students' thinking about certain aspects of…

  10. Testing the Twofold Multidimensionality of Academic Self-Concept: A Study with Chinese Vocational Students

    Science.gov (United States)

    Yang, Lan; Arens, A. Katrin; Watkins, David A.

    2016-01-01

    In order to extend previous research on the twofold multidimensionality of academic self-concept (i.e. its domain-specific structure and separation into competence and affect components), the present study tests its generalisability among vocational students from mainland China. A Chinese version of self-description questionnaire I was…

  11. Reliability, availability and maintenance aspects of large-scale offshore wind farms, a concepts study

    NARCIS (Netherlands)

    Van Bussel, G.J.W.; Zaayer, M.B.

    2001-01-01

    The DOWEC projects aims at implementation of large wind turbines in large scale wind farms. part of the DOWEC project a concepts study was performed regarding the achievable reliability and availability levels. A reduction with a factor of 2 with regard to the present state of the art seems fairly e

  12. Applying Threshold Concepts Theory to an Unsettled Field: An Exploratory Study in Criminal Justice Education

    Science.gov (United States)

    Wimshurst, Kerry

    2011-01-01

    Criminal justice education is a relatively new program in higher education in many countries, and its curriculum and parameters remain unsettled. An exploratory study investigated whether threshold concepts theory provided a useful lens by which to explore student understandings of this multidisciplinary field. Eight high-performing final-year…

  13. Zero-gravity cloud physics laboratory: Experiment program definition and preliminary laboratory concept studies

    Science.gov (United States)

    Eaton, L. R.; Greco, E. V.

    1973-01-01

    The experiment program definition and preliminary laboratory concept studies on the zero G cloud physics laboratory are reported. This program involves the definition and development of an atmospheric cloud physics laboratory and the selection and delineations of a set of candidate experiments that must utilize the unique environment of zero gravity or near zero gravity.

  14. A Classical Test Theory Analysis of the Light and Spectroscopy Concept Inventory National Study Data Set

    Science.gov (United States)

    Schlingman, Wayne M.; Prather, Edward E.; Wallace, Colin S.; Brissenden, Gina; Rudolph, Alexander L.

    2012-01-01

    This paper is the first in a series of investigations into the data from the recent national study using the Light and Spectroscopy Concept Inventory (LSCI). In this paper, we use classical test theory to form a framework of results that will be used to evaluate individual item difficulties, item discriminations, and the overall reliability of the…

  15. Using Concept Maps to Elicit and Study Student Teachers' Perceptions about Inclusive Education: A Tanzanian Experience

    Science.gov (United States)

    Wormnaes, Siri; Mkumbo, Kitila; Skaar, Bjørn; Refseth, Yngve

    2015-01-01

    In this study, concept map activities were used to trigger group discussions about inclusive education, with a focus on learners with disabilities. The participants were 226 Tanzanian student teachers. This article reports and discusses how the maps were analysed and what they indicate about the students' thinking about certain aspects of…

  16. Applying Threshold Concepts Theory to an Unsettled Field: An Exploratory Study in Criminal Justice Education

    Science.gov (United States)

    Wimshurst, Kerry

    2011-01-01

    Criminal justice education is a relatively new program in higher education in many countries, and its curriculum and parameters remain unsettled. An exploratory study investigated whether threshold concepts theory provided a useful lens by which to explore student understandings of this multidisciplinary field. Eight high-performing final-year…

  17. The Temporal Properties of E-Learning: An Exploratory Study of Academics' Conceptions

    Science.gov (United States)

    Martins, Jorge; Nunes, Miguel Baptista

    2016-01-01

    Purpose: The purpose of this paper is to present the results of an exploratory study that investigates Portuguese academics' conceptions concerning the temporal properties of e-learning, in the context of traditional Higher Education Institutions. Design/methodology/approach: Grounded Theory methodology was used to systematically analyse data…

  18. A concept mapping study on perpetuating factors of functional somatic symptoms from clinicians' perspective

    NARCIS (Netherlands)

    Janssens, Karin A M; Houtveen, Jan H; Tak, Lineke M; Bonvanie, Irma J; Scholtalbers, Anna; van Gils, Anne; Geenen, Rinie; Rosmalen, Judith G M

    2017-01-01

    OBJECTIVE: The aim of this concept mapping study was to identify the structure and alleged importance of perpetuating factors of functional somatic symptoms (FSS) from the perspective of professionals. Further, we examined to which extent these factors have been addressed in scientific literature. M

  19. A Study on the Teaching of the Concept of Negative Numbers

    Science.gov (United States)

    Altiparmak, Kemal; Ozdogan, Ece

    2010-01-01

    This study mainly aims to develop an effective strategy to overcome the known difficulties in teaching negative numbers. Another aim is to measure the success of this teaching strategy among a group of elementary level pupils in Izmir, Turkey. Learning negative concepts are supported by computer animations. The academic achievement test developed…

  20. Third-Graders' Conceptions about the Origin of Species before and after Instruction: An Exploratory Study

    Science.gov (United States)

    Berti, Anna Emilia; Barbetta, Valentina; Toneatti, Laura

    2017-01-01

    This study examines how third-graders' conceptions about the origin of species are affected by formal instruction and whether children can learn not only about evolution but also about natural selection. We interviewed the same group of third-grade children (8-9 years old) twice, before and after following a curriculum about these topics.…

  1. Third-Graders' Conceptions about the Origin of Species before and after Instruction: An Exploratory Study

    Science.gov (United States)

    Berti, Anna Emilia; Barbetta, Valentina; Toneatti, Laura

    2017-01-01

    This study examines how third-graders' conceptions about the origin of species are affected by formal instruction and whether children can learn not only about evolution but also about natural selection. We interviewed the same group of third-grade children (8-9 years old) twice, before and after following a curriculum about these topics.…

  2. Prospects of Source-Separation-Based Sanitation Concepts: A Model-Based Study

    NARCIS (Netherlands)

    Tervahauta, T.H.; Trang Hoang,; Hernández, L.; Zeeman, G.; Buisman, C.J.N.

    2013-01-01

    Separation of different domestic wastewater streams and targeted on-site treatment for resource recovery has been recognized as one of the most promising sanitation concepts to re-establish the balance in carbon, nutrient and water cycles. In this study a model was developed based on literature data

  3. A Study on Applying the Concept of Innovation Management to Accounting Curriculum

    Science.gov (United States)

    Cheng, Kai-Wen

    2008-01-01

    This study introduces the concept of innovation management into curriculum design through a 4-month teaching project. Through this process, constant review and modification, and continuous analyses and verifications, two conclusions were obtained: (1) The design of teaching content should be oriented to thinking, sharing, and transfer of learning;…

  4. Concepts and approaches to study disruption and change of everyday life during flash flood events.

    NARCIS (Netherlands)

    Jeuring, Jelmer

    2013-01-01

    Concepts and approaches to study disruption and change of everyday life during flash flood events. The dynamics of extreme precipitations and consequential flash-floods in Southern France lead to important variations in vulnerability of people and property across space and time. In turn, these event

  5. A process approach to children's understanding of scientific concepts : A longitudinal case study

    NARCIS (Netherlands)

    Steen, Steffie van der; Steenbeek, Henderien; Dijk, Marijn van; Geert, Paul van

    2014-01-01

    Using a longitudinal study on childrens’ understanding of scientific concepts, we compare the relative importance of general (e.g., standardized test scores) and microgenetic measures (interaction patterns) to characterize the development of scientific understanding over 1.5 years. A researcher work

  6. Teaching the "Diagonalization Concept" in Linear Algebra with Technology: A Case Study at Galatasaray University

    Science.gov (United States)

    Yildiz Ulus, Aysegul

    2013-01-01

    This paper examines experimental and algorithmic contributions of advanced calculators (graphing and computer algebra system, CAS) in teaching the concept of "diagonalization," one of the key topics in Linear Algebra courses taught at the undergraduate level. Specifically, the proposed hypothesis of this study is to assess the effective…

  7. Definitions of Physical Concepts: A Study of Physics Teachers' Knowledge and Views. Research Report

    Science.gov (United States)

    Galili, Igal; Lehavi, Yaron

    2006-01-01

    A study was made of the ability of a population of high-school physics teachers to define physics concepts and of their views regarding the importance of such definitions. It was found possible to arrange the definitions accumulated in categories, and the classification so obtained was consonant with that of the philosophy of science. Although the…

  8. A Study on Applying the Concept of Innovation Management to Accounting Curriculum

    Science.gov (United States)

    Cheng, Kai-Wen

    2008-01-01

    This study introduces the concept of innovation management into curriculum design through a 4-month teaching project. Through this process, constant review and modification, and continuous analyses and verifications, two conclusions were obtained: (1) The design of teaching content should be oriented to thinking, sharing, and transfer of learning;…

  9. Relational Understanding of the Derivative Concept through Mathematical Modeling: A Case Study

    Science.gov (United States)

    Sahin, Zulal; Aydogan Yenmez, Arzu; Erbas, Ayhan Kursat

    2015-01-01

    The purpose of this study was to investigate three second-year graduate students' awareness and understanding of the relationships among the "big ideas" that underlie the concept of derivative through modeling tasks and Skemp's distinction between relational and instrumental understanding. The modeling tasks consisting of warm-up,…

  10. Density and Flow-Velocity Measurement Technology for Dredging Applications - Proof of Concept Study

    Energy Technology Data Exchange (ETDEWEB)

    Greenwood, Margaret S.; Tucker, Brian J.; Diaz, Aaron A.

    2004-10-01

    This technical letter report provides the results of all PNNL managed activities on this project, and contains a description of the data acquisition configuration and testing protocols, results and conclusions from this work. This technical letter report constitutes the final deliverable to be submitted to the client for this proof-of-concept study.

  11. An Exploratory Study on Principals' Conceptions about Their Role as School Leaders

    Science.gov (United States)

    Devos, Geert; Bouckenooghe, Dave

    2009-01-01

    This inquiry, by means of the case study method, explored how principals' conceptions about their role as school leader contribute to a better understanding of their leadership behavior and how this is related to school climate. The results indicated that differences of how principals conceive their leadership role are related, indirectly through…

  12. 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

  13. A concept mapping study on organic food consumers in Shanghai, China.

    Science.gov (United States)

    Hasimu, Huliyeti; Marchesini, Sergio; Canavari, Maurizio

    2017-01-01

    Despite some similarities with developed countries, the growth of organic market in China seems to follow a different path. Thus, important questions are how Chinese urban consumers perceive organic food, and what are the main concepts associated to the organic attribute. We aimed at representing in graphic form the network of mental associations with the organic concept. We used an adapted version of the "Brand concept mapping" method to acquire, process, and draw individual concept networks perceived by 50 organic food consumers in Shanghai. We then analyzed the data using network and cluster analysis to create aggregated maps for two distinct groups of consumers. Similarly to their peers in developed countries, Chinese consumers perceive organic food as healthy, safe and expensive. However, organic is not necessarily synonymous with natural produce in China, also due to a translation of the term that conveys the idea of a "technology advanced" product. Organic overlaps with the green food label in terms of image and positioning in the market, since they are easily associated and often confused. The two groups we identified show clear differences in the way the organic concept is associated to other concepts and features. The study provides useful information for practitioners: marketers of organic products in China should invest in communication to emphasize the differences with Green Food products and they should consider the possibility of segmenting organic consumers; Chinese policy makers should consider implementing information campaigns aimed at achieving a better understanding of the features of these quality labels among consumers. For researchers, the study confirms that the BCM method is effective and its integration with network and cluster analysis improves the interpretation of individual and aggregated maps.

  14. Flood hazard and flood risk assessment using a time series of satellite images: a case study in Namibia.

    Science.gov (United States)

    Skakun, Sergii; Kussul, Nataliia; Shelestov, Andrii; Kussul, Olga

    2014-08-01

    In this article, the use of time series of satellite imagery to flood hazard mapping and flood risk assessment is presented. Flooded areas are extracted from satellite images for the flood-prone territory, and a maximum flood extent image for each flood event is produced. These maps are further fused to determine relative frequency of inundation (RFI). The study shows that RFI values and relative water depth exhibit the same probabilistic distribution, which is confirmed by Kolmogorov-Smirnov test. The produced RFI map can be used as a flood hazard map, especially in cases when flood modeling is complicated by lack of available data and high uncertainties. The derived RFI map is further used for flood risk assessment. Efficiency of the presented approach is demonstrated for the Katima Mulilo region (Namibia). A time series of Landsat-5/7 satellite images acquired from 1989 to 2012 is processed to derive RFI map using the presented approach. The following direct damage categories are considered in the study for flood risk assessment: dwelling units, roads, health facilities, and schools. The produced flood risk map shows that the risk is distributed uniformly all over the region. The cities and villages with the highest risk are identified. The proposed approach has minimum data requirements, and RFI maps can be generated rapidly to assist rescuers and decisionmakers in case of emergencies. On the other hand, limitations include: strong dependence on the available data sets, and limitations in simulations with extrapolated water depth values.

  15. Estimating daily surface NO2 concentrations from satellite data - a case study over Hong Kong using land use regression models

    Science.gov (United States)

    Anand, Jasdeep S.; Monks, Paul S.

    2017-07-01

    Land use regression (LUR) models have been used in epidemiology to determine the fine-scale spatial variation in air pollutants such as nitrogen dioxide (NO2) in cities and larger regions. However, they are often limited in their temporal resolution, which may potentially be rectified by employing the synoptic coverage provided by satellite measurements. In this work a mixed-effects LUR model is developed to model daily surface NO2 concentrations over the Hong Kong SAR during the period 2005-2015. In situ measurements from the Hong Kong Air Quality Monitoring Network, along with tropospheric vertical column density (VCD) data from the OMI, GOME-2A, and SCIAMACHY satellite instruments were combined with fine-scale land use parameters to provide the spatiotemporal information necessary to predict daily surface concentrations. Cross-validation with the in situ data shows that the mixed-effects LUR model using OMI data has a high predictive power (adj. R2 = 0. 84), especially when compared with surface concentrations derived using the MACC-II reanalysis model dataset (adj. R2 = 0. 11). Time series analysis shows no statistically significant trend in NO2 concentrations during 2005-2015, despite a reported decline in NOx emissions. This study demonstrates the utility in combining satellite data with LUR models to derive daily maps of ambient surface NO2 for use in exposure studies.

  16. Satellite remote sensing of Asian aerosols: a case study of clean, polluted, and Asian dust storm days

    Directory of Open Access Journals (Sweden)

    K. H. Lee

    2010-12-01

    Full Text Available In East Asia, satellite observation is important because aerosols from natural and anthropogenic sources have been recognized as a major source of regional and global air pollution. However, retrieving aerosols properties from satellite observations over land can be difficult because of the surface reflection, complex aerosol composition, and aerosol absorption. In this study, a new aerosol retrieval method called as the Moderate Resolution Imaging Spectroradiometer (MODIS satellite aerosol retrieval (MSTAR was developed and applied to three different aerosol event cases over East Asia. MSTAR uses a separation technique that can distinguish aerosol reflectance from top-of-atmosphere (TOA reflectance. The aerosol optical thickness (AOT was determined by comparing this aerosol reflectance with pre-calculated values. Three case studies show how the methodology identifies discrepancies between measured and calculated values to retrieve more accurate AOT. The comparison between MODIS and the Aerosol Robotic Network (AERONET showed improvement using the suggested methodology with the cluster-based look-up-tables (LUTs (linear slope = 0.94, R = 0.92 than using operational MODIS collection 5 aerosol products (linear slope = 0.78, R = 0.87. In conclusion, the suggested methodology is shown to work well with aerosol models acquired by statistical clustering of the observation data in East Asia.

  17. Study of landwater variation over Chao Phraya river basin using GRACE, satellite altimetry and in situ data

    Science.gov (United States)

    Yamamoto, K.; Fukuda, Y.; Nakaegawa, T.; Taniguchi, M.

    2009-12-01

    A project to assess the effects of human activities on the subsurface environment in Asian developing cities has been in progress (Research Institute for Humanity and Nature, Japan, 2009). Bangkok, Thailand is one of the study cities in this project. Using GRACE satellite gravity data, we previously recovered landwater mass variation over the Chao Phraya river basin, where Bangkok is located on downstream. However, mainly because of insufficient spatial resolution of the GRACE data then released, it was difficult to distinguish mass variation over the Chao Phraya basin with the ones of the neighboring Mekong, Irrawaddy and Salween river basins. Recently, some new versions of GRACE data sets have been available, and thus we estimated again the mass variations over these basins using version 2 of CNS/GRGS data set. The result shows that mass variations of the each basin could be distinguished due to improvement of the spatial resolution of the data. One of the interesting things is that a negative interannual mass trend is observed only over the Chao Phraya river basin, while the other basins show positive trend values. One of our concerns was which of the landwater components were decreasing. Because GRACE can only detect total terrestrial water storage, we further used satellite altimeter data to separate surface- and groundwater components. EnviSat data were mainly used as satellite altimetry data in this study, because the mission period is overlapping with GRACE mission and the ground track separation is relatively small. River water levels were recovered from satellite altimetry data, and converted to river water storage. Estimated river water storage was subtracted from the GRACE data. Thus, interannual surface- and groundwater trends were discussed separately. Another concern is whether the landwater decrease is caused by meteorological factors or factors of human activities. Thus, we also compared above results with global hydrological simulation model and

  18. The MSFC Collaborative Engineering Process for Preliminary Design and Concept Definition Studies

    Science.gov (United States)

    Mulqueen, Jack; Jones, David; Hopkins, Randy

    2011-01-01

    This paper describes a collaborative engineering process developed by the Marshall Space Flight Center's Advanced Concepts Office for performing rapid preliminary design and mission concept definition studies for potential future NASA missions. The process has been developed and demonstrated for a broad range of mission studies including human space exploration missions, space transportation system studies and in-space science missions. The paper will describe the design team structure and specialized analytical tools that have been developed to enable a unique rapid design process. The collaborative engineering process consists of integrated analysis approach for mission definition, vehicle definition and system engineering. The relevance of the collaborative process elements to the standard NASA NPR 7120.1 system engineering process will be demonstrated. The study definition process flow for each study discipline will be will be outlined beginning with the study planning process, followed by definition of ground rules and assumptions, definition of study trades, mission analysis and subsystem analyses leading to a standardized set of mission concept study products. The flexibility of the collaborative engineering design process to accommodate a wide range of study objectives from technology definition and requirements definition to preliminary design studies will be addressed. The paper will also describe the applicability of the collaborative engineering process to include an integrated systems analysis approach for evaluating the functional requirements of evolving system technologies and capabilities needed to meet the needs of future NASA programs.

  19. Proceedings of the Seventeenth NASA Propagation Experimenters Meeting (NAPEX 17) and the Advanced Communications Technology Satellite (ACTS) Propagation Studies Miniworkshop

    Science.gov (United States)

    Davarian, Faramaz (Editor)

    1993-01-01

    The NASA Propagation Experimenters Meeting (NAPEX) is convened annually to discuss studies made on radio wave propagation by investors from domestic and international organizations. NAPEX 17 was held on 15 June 1993. The meeting was organized into two technical sessions. The first session was dedicated to slant path propagation studies and experiments. The second session focused on propagation studies for mobile and personal communications. Preceding NAPEX 17, the Advanced Communications Technology Satellite (ACTS) Propagation Studies Miniworkshop was held on 14 June 1993 to review ACTS propagation activities with emphasis on ACTS experiments status and data collection, processing, and exchange.

  20. A Cusp Density Enhancement Study using e-POP Satellite Data

    Science.gov (United States)

    Sadler, B.

    2015-12-01

    CHAMP satellite observations have confirmed neutral density enhancements which are localized to the high latitude polar cusp region. These small-scale density structures are consistently correlated with strong fine-scale field-aligned currents. A possible driver of these density enhancements is soft electron precipitation which, through processes associated with ion-outflow, results in a density enhancement in the cusp vicinity at the altitudes observed by CHAMP. We investigate this mechanism with recent observations from the CASSIOPE / e-POP satellite and numerical simulations. In-situ data for selected cusp transit events are presented. Numerical simulation predictions are discussed comparing two electron-precipitation models: a fine-scale ion-outflow model and a global-scale Joule heating / increased conductivity model (CMIT).