WorldWideScience

Sample records for open space control

  1. An Open Specification for Space Project Mission Operations Control Architectures

    Science.gov (United States)

    Hooke, A.; Heuser, W. R.

    1995-01-01

    An 'open specification' for Space Project Mission Operations Control Architectures is under development in the Spacecraft Control Working Group of the American Institute for Aeronautics and Astro- nautics. This architecture identifies 5 basic elements incorporated in the design of similar operations systems: Data, System Management, Control Interface, Decision Support Engine, & Space Messaging Service.

  2. Virtual Visit to the ATLAS Control Room by Open Discovery Space webinar in Europe

    CERN Multimedia

    2013-01-01

    Open Discovery Space (ODS) is a socially-powered and multilingual open learning infrastructure to boost the adoption of eLearning resources. ODS brings millions of educational resources directly into school classrooms. A key part of planning engaging lessons is access to high-quality, trustworthy teaching content. The platform empowers teachers by helping them build their schools` digital libraries, join lively communities of peers to share best practices, and connect their schools virtually with the world`s best research centres, museums and libraries.

  3. Open Spaces, Public Spaces, Publics, Open-minded Places

    Directory of Open Access Journals (Sweden)

    Luisa Bravo

    2013-05-01

    Full Text Available In 1993 a double issue of the international architectural review (published in Italy “Casabella” was dedicated to “The design of open spaces”. Different positions and scholars and diverse point of views explored this complex theme, trying to explain the reasons, the modes and the possibilities of a new strategy in design research and practice. The starting point was the very term “open space”, which doesn’t belong to the classical vocabulary of architectural theory, with no reference to modern town planning manuals.Nowadays the difference between “open space”, as indicated in regulations of urban city spaces, and “public space” has found new declensions related to public life of groups or individuals, taking place in consolidated environments as well as in peripheral areas or in residual spaces up to edge cities, able to give values and functions to neglected or abandoned places. Next to public meeting spaces, such as large congress hall, fair precincts, political or cultural events, shopping centers, and to waiting spaces, such as offices, public institutions, underground stations, airports, many public spaces do not have an architectural connotation: life can be found at the corner of two suburban roads, where spontaneous conversation or some kind of special event slowly starts to layer, indicating a kind of rituality, or in anonymous suburban places where minority ethnic or immigrant groups gather, becoming places of solidarity and sharing. All these expressions, as already Vittorio Gregotti pointed out in his introductory essay on Casabella, articulate in a new way the demands for public space and for its architectural definition.

  4. Occupancy-based lighting control in open-plan office spaces : A state-of-the-art review

    OpenAIRE

    de Bakker, C Christel; Aries, MBC Myriam; Kort, HSM Helianthe; Rosemann, ALP Alexander

    2017-01-01

    Lighting accounts for a significant amount of electrical energy consumption in office buildings, up to 45% of the total consumed. This energy consumption can be reduced by as much as 60% through an occupant-dependent lighting control strategy. With particular focus on open-plan offices, where the application of this strategy is more challenging to apply due to differences in individual occupancy patterns, this paper covers (1) to which extent individual occupancy-based lighting control has be...

  5. Open architecture robot control based on Matlab/Simulink and a dSPACE real time system

    Science.gov (United States)

    Heuer, Kerstin; Pokar, Gero; Hesselbach, Juergen

    2004-03-01

    The elements of an open architecture robot control system developed using Matlab/Simulink and a real time system are described. It offers the opportunity to control almost every robotic system (serial or parallel) with up to six axes while commercial robot controls are often designed for serial kinematic systems and can hardly be adapted to control robots with parallel structures. The described open architecture robot control programmed in Matlab/Simulink and ANSI-C is a modular system. To adapt the control to a new robotic structure it is necessary to add the transformation algorithms, position control algorithms, inputs and outputs and machine specific error states to the pre-programmed modules of the system. These modules are programmed by using Simulink elements extended by special functions of the real time system and so called S-Functions that are programmed in C-Code. In the control new functionalities can be implemented easily by adding new modules and connecting them with the present system. A pre-designed graphical user interface provides most of the input buttons and display information needed for a robot control. Graphical buttons or displays can be added and connected with the required signal from Matlab/Simulink by drag and drop. An application example of a parallel robot shows the functionalities of the control.

  6. Using Open Space Technology for School Improvement.

    Science.gov (United States)

    Cox, David

    2002-01-01

    Describes a theory referred to as Open Space Technology (OST), which holds that the most productive learning in conference settings takes place in the open space between formally scheduled conference sessions. Argues that OST can be applied to staff development days and other educational development programs. (Contains 10 references.) (NB)

  7. The Spaces of Open-Source Politics

    DEFF Research Database (Denmark)

    Husted, Emil; Plesner, Ursula

    constructed by the Alternative as techniques for practicing open-source politics, and observe that physical and digital spaces create a vacillation between openness and closure. This vacillation produces a dialectic relationship between practices of imagination and affirmation. Curiously, it seems...

  8. Space Shuttle flight control system

    Science.gov (United States)

    Klinar, W. J.; Kubiak, E. T.; Peters, W. H.; Saldana, R. L.; Smith, E. E., Jr.; Stegall, H. W.

    1975-01-01

    The Space Shuttle is a control stabilized vehicle with control provided by an all digital, fly-by-wire flight control system. This paper gives a description of the several modes of flight control which correspond to the Shuttle mission phases. These modes are ascent flight control (including open loop first stage steering, the use of four computers operating in parallel and inertial guidance sensors), on-orbit flight control (with a discussion of reaction control, phase plane switching logic, jet selection logic, state estimator logic and OMS thrust vector control), entry flight control and TAEM (terminal area energy management to landing). Also discussed are redundancy management and backup flight control.

  9. Active Control of Open Cavities

    Science.gov (United States)

    UKeiley, Lawrence

    2010-01-01

    Open loop edge blowing was demonstrated as an effective method for reducing the broad band and tonal components of the fluctuating surface pressure in open cavities. Closed loop has been successfully applied to low Mach number open cavities. Need to push actuators that are viable for closed loop control in bandwidth and output. Need a better understanding of the effects of control on the flow through detailed measurements so better actuation strategies can be developed.

  10. 46 CFR 45.149 - Machinery space openings.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Machinery space openings. 45.149 Section 45.149 Shipping... Assignment § 45.149 Machinery space openings. (a) Machinery space openings in position 1 or 2 must be framed... funnel or machinery space ventilator that must be kept open for the essential operations of the ship...

  11. Healthy campus by open space design: Approaches and guidelines

    Directory of Open Access Journals (Sweden)

    Stephen Siu Yu Lau

    2014-12-01

    Full Text Available This paper examines the architectural and landscape design strategies and intentions for green, open spaces facilities targeting stress alleviation for learning environments such as those of university campuses in a compact urban setting. Literature reviews provide three prevailing perspectives for physical design pedagogical operatives: healing gardens where greenery and plants produce restorative effects; flexible spaces that accommodate functional needs of different activities; and green buildings that incorporate open space as a catalyst for integrated eco-system. Corresponding design approaches (landscape design, spatial design and green design are scrutinized by case study. A comparison of two university campuses with different urban contexts is conducted to identify challenges and opportunities for applying these design approaches. For a compact campus, high-dense surroundings may limit the size of an open space and may handicap circulation and accessibility; on the other side, a small open space may provide its users more intimate contact with natural restorative elements and also a more controllable microclimate for physical comfort. A healthy campus should encompass diverse open spaces to satisfy different purposes. Finally, a framework that integrates the three approaches is combined to produce a sustainable design rubric.

  12. A Monstrous Alliance: Open Architecture and Common Space

    Directory of Open Access Journals (Sweden)

    Gökhan Kodalak

    2015-06-01

    Full Text Available The contemporary built environment is absorbed by a dualist spatial organisation model divided between public and private space. Within this restrictive grammar, public space, despite its democratic promise, is heavily indoctrinated and anesthetised under the hegemony of regulatory apparatuses and control mechanisms, whereas private space has catalysed, if not directly engendered, prevalent spatial problems, such as ever-increasing slums, discriminatory gentrification and ecological catastrophes, despite its self-approving assurance. Underneath this dysfunctional couple lies common space, a third category that constitutes the shared spatial commonwealth of our entire natural and cultural milieu.The multitude, as an emerging body of self-organising political and spatial actors, has already started to unearth the potential of common space, actualising emergent and interactive spatial configurations all around the world. In this new, self-organisational model, architects do not become obsolete; rather, they leave behind their conventional roles as submissive experts and cosmetic speculators. By becoming anomalous architects, they affirm and augment the opening of spatial and architectural milieus to a myriad of new possibilities.This article theorises the possibility of a monstrous alliance between anomalous architects and the multitude, between open architectures and common space. Two specific case studies accompany these theoretical frameworks: the Gezi Event (Istanbul, 2013 demonstrates the actual emancipation of common space through the self-organising activity of the multitude, while Open-Cube (Antalya, 2013 attests to an early open architecture experiment based on the potentiating activity of the anomalous architect. 

  13. Open space preservation, property value, and optimal spatial configuration

    Science.gov (United States)

    Yong Jiang; Stephen K. Swallow

    2007-01-01

    The public has increasingly demonstrated a strong support for open space preservation. How to finance the socially efficient level of open space with the optimal spatial structure is of high policy relevance to local governments. In this study, we developed a spatially explicit open space model to help identify the socially optimal amount and optimal spatial...

  14. Restorative urban open space: Exploring the spatial configuration of human emotional fulfilment in urban open space

    OpenAIRE

    Thwaites, K.; Helleur, E.; Simkins, I.M.

    2005-01-01

    The capacity of outdoor settings to benefit human well being is well established by research. Examples of restorative settings can be found throughout history and are still applied today in health-care facilities, as healing or restorative gardens for the sick, but their wider significance in the urban public realm remains insufficiently explored. A conceptual framework for restorative urban open space based on mosaics of linked and nested spaces woven into the urban fabric is presented. The ...

  15. Open loop control of an induction motor's velocity using PWM with space vectors; Control en lazo abierto de la velocidad de un motor de induccion utilizando PWM con vectores espaciales

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Lopez, Manuel

    2001-10-15

    This work describes the design and implementation of an open loop speed controller for an induction motor. This controller is based on a DSP TMS320F240 chip from Texas Instruments. Speed control is achieved by maintaining the magnetic flux constant through the regularization of stator voltage/frequency relationship. Voltage and frequency variation are achieved using the strategy of pulse width modulation with space vectors. Hardware design is presented (current source and the printed circuit for the intelligent power module) and the software (control algorithms and the modulation strategy using space vectors). The algorithms given were implement using the TMS320F240 language. [Spanish] Este trabajo describe el diseno y la implementacion de un control de la velocidad en lazo abierto de un motor de induccion, basado en el DSP TMS320F240 de Texas Instruments. El control de la velocidad se logra manteniendo el flujo en el entre hierro constante, lo cual es realizado al regular el valor de la relacion voltaje/frecuencia en el estator. La variacion del voltaje y la frecuencia se realiza utilizando la estrategia de modulacion del ancho de los pulsos con vectores espaciales. Se presenta el diseno de los circuitos (fuente de corriente continua y circuito impreso para el modulo inteligente de potencia) y de los programas (algoritmos de control y de la estrategia de modulacion con vectores espaciales) necesarios que se utilizaron durante la implementacion del accionamiento del motor. Los algoritmos dados fueron implementados en el lenguaje ensamblador del TMS320F240.

  16. 46 CFR 42.15-35 - Machinery space openings.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Machinery space openings. 42.15-35 Section 42.15-35... BY SEA Conditions of Assignment of Freeboard § 42.15-35 Machinery space openings. (a) Machinery space..., funnel, or machinery space ventilators in an exposed position on the freeboard or superstructure...

  17. Space as an open plasma laboratory

    Science.gov (United States)

    Papadopoulos, Konstantinos

    2011-10-01

    Ionospheric heaters supplemented by ground and space based diagnostic instruments have for a long time being used to conduct plasma physics, geophysical and radio science investigations. The recently completed HF transmitter associated with the High Frequency Active Ionospheric Research Program (HAARP), far exceeds the capabilities of previous ionospheric heaters and allows for new frontier research in plasma physics, geophysics and radio science. The transmitter radiates 3.6 MW of HF power in the 2.8-10.0 MHz frequency range. The beam-width varies from 15-5 degrees, corresponding to 20-30 dB gain and resulting in Effective Radiating Power (ERP) between.36-4.0 GW. The antenna can point to any direction in a cone of 30 degrees from the vertical, with a reposition time of 15 degrees in 15 microseconds resulting in super-luminous scanning speeds. The transmitter can synthesize essentially any desired waveform in linear and circular polarization. We present a number of HAARP experiments that used space as an open plasma laboratory. The experiments cover the areas of (i) Artificial ULF/ELF/VLF generation and injection in the magnetosphere (ii) Studies of wave-particle interactions in the magnetosphere (iii) Langmuir turbulence, parametric instabilities, electron acceleration and optical emissions (iv) Artificial ionization. Ionospheric heaters supplemented by ground and space based diagnostic instruments have for a long time being used to conduct plasma physics, geophysical and radio science investigations. The recently completed HF transmitter associated with the High Frequency Active Ionospheric Research Program (HAARP), far exceeds the capabilities of previous ionospheric heaters and allows for new frontier research in plasma physics, geophysics and radio science. The transmitter radiates 3.6 MW of HF power in the 2.8-10.0 MHz frequency range. The beam-width varies from 15-5 degrees, corresponding to 20-30 dB gain and resulting in Effective Radiating Power (ERP

  18. Elements that influence living quality in open urban space

    Directory of Open Access Journals (Sweden)

    Petra Krajner

    2007-01-01

    Full Text Available The number of people living in cities in Slovenia is increasing. There fore, the city spreads, urban space is created mostly by different buildings with minimum of open space, usually designed for parking spaces. But despite the fact, that urban structure is spreading, and there should be more of public open spaces, or green open spaces, those are in many cases reached by developers as well. Despite global worming, higher temperatures in city centres and what appears to be what citizens want, the urban open spaces are not big enough, and are usually not designed with key elements, to improve quality of lifestyle in the urban space such as trees, water or natural elements. Therefore at all levels of urban planning it is necessary to strive for larger amount of space that could be designed as public open space or green space to improve quality of life in the city.

  19. Sound preferences in urban open public spaces

    Science.gov (United States)

    Kang, Jian; Yang, Wei

    2003-10-01

    This paper studies people's perception of sound, based on an intensive questionnaire survey in fourteen urban open public spaces of five European countries. The questionnaire includes identification of recognized sounds, classification of sound preference, and indication of wanted and unwanted sounds. The results indicate three facets to people's sound preferences. First, people generally prefer natural and culture-related sounds rather than artificial sounds. Vehicle sounds and construction sounds are regarded as the most unpopular, whereas sounds from human activities are normally rated as neutral. Second, cultural background and long-term environmental experience play an important role in people's judgment of sound preference. People from a similar environment may show a similar tendency on their sound preferences, which can be defined as macro-preference. Third, personal differences, such as age and gender, further influence people's sound preference, which can be defined as micro-preference. For example, with increasing age, a higher percentage of people are favorable to, or tolerate, sounds relating to nature, culture or human activities. Male and female exhibit only slight differences. [Work supported by the European Commission.

  20. Space Digital Controller for Improved Motor Control

    Science.gov (United States)

    Alves-Nunes, Samuel; Daras, Gaetan; Dehez, Bruno; Maillard, Christophe; Bekemans, Marc; Michel, Raymond

    2014-08-01

    Performing digital motor control into space equipment is a new challenge. The new DPC (Digital Programmable Controller) is the first chip that we can use as a micro-controller, allowing us to drive motors with digital control schemes. In this paper, the digital control of hybrid stepper motors is considered. This kind of motor is used for solar array rotation and antenna actuation. New digital control technology brings a lot of advantages, allowing an important reduction of thermal losses inside the motor, and a reduction of thermal constraints on power drive electronic components. The opportunity to drive motors with a digital controller also brings many new functionalities like post-failure torque analysis, micro- vibrations and cogging torque reduction, or electro- mechanical damping of solar array oscillations. To evaluate the performance of the system, Field-Oriented Control (FOC) is implemented on a hybrid stepper motor. A test-bench, made of an active load, has been made to emulate the mechanical behaviour of the solar array, by the use of a torsionally-compliant model. The experimental results show that we can drastically reduce electrical power consumption, compared with the currently used open-loop control scheme.

  1. 78 FR 18416 - Commercial Space Transportation Advisory Committee; Open Meeting

    Science.gov (United States)

    2013-03-26

    ... Federal Aviation Administration Commercial Space Transportation Advisory Committee; Open Meeting AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Commercial Space Transportation Advisory.... 92-463, 5 U.S.C. App. 2), notice is hereby given of a meeting of the Commercial Space...

  2. 78 FR 53496 - Commercial Space Transportation Advisory Committee; Open Meeting

    Science.gov (United States)

    2013-08-29

    ... Federal Aviation Administration Commercial Space Transportation Advisory Committee; Open Meeting AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Commercial Space Transportation Advisory.... 92-463, 5 U.S.C. App. 2), notice is hereby given of a meeting of the Commercial Space...

  3. Courts and open spaces in the Late Helladic III Argolid

    DEFF Research Database (Denmark)

    Siennicka, Malgorzata

    2015-01-01

    and significance of courts and other open spaces in the Mycenaean settlements in the Argolid during the Palatial and Post-Palatial periods (c. 15th–11th centuries BC). Various categories of areas, like courts, open spaces and open-air areas are discussed, with an emphasis on their functions and status. Courts......While space remains a neglected subject in research on Mycenaean settlements, archaeological and ethnographical studies devoted to social meaning of places and areas used by the inhabitants of the prehistoric and other communities increase in number. This paper aims to review the use...... and open spaces are considered as reflecting patterns of spatial organization in the settlements and of the diverse activities of their residents. The differences between the use of open areas in the acropoleis and in the lower towns are pointed out, as well as changes in the use patterns after the fall...

  4. Wide Open Spaces: Wikis Ready or Not

    Science.gov (United States)

    Lamb, Brian

    2004-01-01

    Remember when the Internet was about opening up access to information and breaking down the barriers between content creators and content consumers? Think back to when spam was just a meatlike substance. To those heady days when Timothy Leary was predicting that the PC would be the LSD of the nineties. Before the DMCA. Before eBay. Back when the…

  5. Wide Open Spaces: Wikis Ready or Not

    Science.gov (United States)

    Lamb, Brian

    2004-01-01

    Remember when the Internet was about opening up access to information and breaking down the barriers between content creators and content consumers? Think back to when spam was just a meatlike substance. To those heady days when Timothy Leary was predicting that the PC would be the LSD of the nineties. Before the DMCA. Before eBay. Back when the…

  6. Controls on open water evaporation

    Directory of Open Access Journals (Sweden)

    R. J. Granger

    2010-05-01

    Full Text Available The paper presents the initial results of a field study of boundary layer behaviour and open water evaporation carried out on two small- to medium-sized lakes in Western and Northern Canada. Meteorological and boundary layer measurements were made over the water surfaces and over the upwind land surface, allowing for an examination of the effect of lake-land contrasts of temperature on the wind speed over the open water and on the evaporation rates. Lake evaporation was measured directly using eddy covariance equipment.

    The study showed that, for time periods shorter than daily, the open water evaporation bears no relationship to the net radiation. The wind speed is the most significant factor governing the evaporation rates, followed by the land-water temperature contrast and the land-water vapour pressure contrast. The effect of the stability on the wind field is demonstrated; stability over the water and adjacent land surfaces are, for the most part, out of phase. The derived relationships will be used to develop a model for estimating the hourly evaporation rates from open water.

    Examination of the seasonal trends shows that the open water period can be separated into two distinct evaporative regimes: the warming period in the Spring, when the land temperature is greater than the water temperature, the turbulent fluxes over water are suppressed; and the cooling period, when the water temperature is greater than the air temperature, and the turbulent fluxes over water are enhanced.

  7. An Opened-Intelligent Parking Lot and Design of Parking Space Control System%一种开放式智能停车场及其停车位控制系统设计①

    Institute of Scientific and Technical Information of China (English)

    古辉; 李侠君

    2013-01-01

    提出了一种基于磁阻感应技术与无线传感网络技术相结合的开放式智能停车场的控制与管理技术方案。开放式智能停车场的基本单元是停车位的控制部件设计,方案中应用磁阻感应技术设计了地磁传感器,自动检测和确定车位中有无车辆以及停泊车辆的离开意图,通过构建无线传感网络,实现整个开放式智能停车场系统的管理。%We present a kind of intelligent parking lot which is open style in this paper. We called it Opened-Intelligent Parking. It is a technological solution of management which is based on the combining of the geomagnetic sensor and Wireless Sensor Network technology. The Opened-Intelligent Parking lot's basic unit is the designing of the parking space's control unit. It can detect cars automatically as well as the purpose of leaving with the geomagnetic sensor. The Opened-Intelligent Parking uses Wireless Sensor Network technology to sending messages to manage the system of the whole Opened-Intelligent Parking.

  8. Hyperconnectivity, Attribute-Space Connectivity and Path Openings : Theoretical Relationships

    NARCIS (Netherlands)

    Wilkinson, M.H.F.; Wilkinson, MHF; Roerdink, JBTM

    2009-01-01

    In this paper the relationship of hyperconnected filters with path openings and attribute-space connected filters is studied. Using a recently developed axiomatic framework based on hyperconnectivity operators, which are the hyperconnected equivalents of connectivity openings, it is shown that path

  9. 77 FR 52108 - Commercial Space Transportation Advisory Committee; Open Meeting

    Science.gov (United States)

    2012-08-28

    ... TRANSPORTATION Federal Aviation Administration Commercial Space Transportation Advisory Committee; Open Meeting AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Commercial Space Transportation... Act (Pub. L. 92-463, 5 U.S.C. App. 2), notice is hereby given of a meeting of the Commercial...

  10. Randomized control of open quantum systems

    CERN Document Server

    Viola, L

    2006-01-01

    The problem of open-loop dynamical control of generic open quantum systems is addressed. In particular, I focus on the task of effectively switching off environmental couplings responsible for unwanted decoherence and dissipation effects. After revisiting the standard framework for dynamical decoupling via deterministic controls, I describe a different approach whereby the controller intentionally acquires a random component. An explicit error bound on worst-case performance of stochastic decoupling is presented.

  11. DESIGN OF URBAN OPEN SPACES FOR USER NEEDS

    Directory of Open Access Journals (Sweden)

    Zerrin İnan

    2008-04-01

    Full Text Available The researches done in both the natural and built environments suggest that inspired design can make significant improvements in the lives of people and the environment. While considerable numbers of studies have been done on user needs and conflicts in open space, no single document integrates all of this knowledge and makes it available to professionals, students and researchers. This article aims to review and synthesize the knowledge addressing basic user needs that include comfort, relaxation, passive and active engagements, privatization of public space etc. Also gives some suggestions for reducing conflict among various groups competing for the use of open space in order to be created successful urban open spaces. More researches in the form of new case studies needed to show how user needs can be effectively translated into design. Programming, planning, design and management based on human needs will be essential to the future development of open spaces as well as the growth of the professions designing for open spaces.

  12. Backstepping feedback control of open channel flow

    OpenAIRE

    Huo, Mandy; Malek, Sami

    2014-01-01

    We derive a feedback control law for the control of the downstream flow in a 1-D open channel by manipulating the water flow at an upstream location. We use backstepping for controller design and Lyapunov techniques for stability analysis. Finally, the controller is verified with simulations.

  13. Open problems in the geometry and analysis of Banach spaces

    CERN Document Server

    Guirao, Antonio J; Zizler, Václav

    2016-01-01

    This is a collection of some easily-formulated problems that remain open in the study of the geometry and analysis of Banach spaces. Assuming the reader has a working familiarity with the basic results of Banach space theory, the authors focus on concepts of basic linear geometry, convexity, approximation, optimization, differentiability, renormings, weak compact generating, Schauder bases and biorthogonal systems, fixed points, topology and nonlinear geometry. The main purpose of this work is to help convince young researchers in Functional Analysis that the theory of Banach spaces is a fertile field of research, full of interesting open problems. Inside the Banach space area, the text should help expose young researchers to the depth and breadth of the work that remains, and to provide the perspective necessary to choose a direction for further study. Some of the problems presented herein are longstanding open problems, some are recent, some are more important and some are only "local" problems. Some would ...

  14. Soundscape of Urban Open Spaces in Hong Kong

    Science.gov (United States)

    Lin, Hui

    This study aims to investigate the soundscape of urban open spaces in Hong Kong. Open space in densely populated cities has been considered as an important asset for urban inhabitants in that they afford opportunities for leisure, recreation and an active involvement with nature. For quite a long time, visual aesthetic was the dominant consideration in open space design and other senses were given less concern. Continuous stream of attention-demanding sounds from the noisy environment may bombard these open spaces, rendering them no longer able to satisfy the eye alone. Sound and consequently the acoustic environment are receiving increasing attention. This study used noise mapping technique supplemented by GIS spatial analysis tools to delineate quiet open spaces with traffic noise exposure less than 60 dB (A) L10, 1h and conducted field observations to determine their usages. The identified quiet open spaces are either concentrated in hilly and remote areas with low accessibility, or sporadically scattered among tall buildings. Some large urban parks and small sitting-out areas are even located in the center of the city. Larger open spaces serve group visits, such as hiking and sightseeing, while smaller ones are easily accessible to local residents for social and recreational purposes. The acoustic environment III urban open spaces varies with space and time. To characterize the acoustic quality of soundscapes in the quiet open spaces, sound walk and field recording were undertaken place in 25 selected study sites. Despite the dominance of traffic noise, soundscapes in the urban open spaces are also shaped by natural sounds. Sounds from birds and water are common and prevalent particularly in gardens and playgrounds. Soundscape approach is a human-centered point of view. How the visitors perceive and evaluate sounds and the acoustic quality has great implication for soundscape design. On-site interview of 1,610 visitors unravels human preference of individual

  15. Open control/display system for a telerobotics work station

    Science.gov (United States)

    Keslowitz, Saul

    1987-01-01

    A working Advanced Space Cockpit was developed that integrated advanced control and display devices into a state-of-the-art multimicroprocessor hardware configuration, using window graphics and running under an object-oriented, multitasking real-time operating system environment. This Open Control/Display System supports the idea that the operator should be able to interactively monitor, select, control, and display information about many payloads aboard the Space Station using sets of I/O devices with a single, software-reconfigurable workstation. This is done while maintaining system consistency, yet the system is completely open to accept new additions and advances in hardware and software. The Advanced Space Cockpit, linked to Grumman's Hybrid Computing Facility and Large Amplitude Space Simulator (LASS), was used to test the Open Control/Display System via full-scale simulation of the following tasks: telerobotic truss assembly, RCS and thermal bus servicing, CMG changeout, RMS constrained motion and space constructible radiator assembly, HPA coordinated control, and OMV docking and tumbling satellite retrieval. The proposed man-machine interface standard discussed has evolved through many iterations of the tasks, and is based on feedback from NASA and Air Force personnel who performed those tasks in the LASS.

  16. OPEN PUBLIC SPACE ATTRIBUTES AND CATEGORIES – COMPLEXITY AND MEASURABILITY

    Directory of Open Access Journals (Sweden)

    Ljiljana Čavić

    2014-12-01

    Full Text Available Within the field of architectural and urban research, this work addresses the complexity of contemporary public space, both in a conceptual and concrete sense. It aims at systematizing spatial attributes and their categories and discussing spatial complexity and measurability, all this in order to reach a more comprehensive understanding, description and analysis of public space. Our aim is to improve everyday usage of open public space and we acknowledged users as its crucial factor. There are numerous investigations on the complex urban and architectural reality of public space that recognise importance of users. However, we did not find any that would holistically account for what users find essential in public space. Based on the incompleteness of existing approaches on open public space and the importance of users for their success, this paper proposes a user-orientated approach. Through an initial survey directed to users, we collected the most important aspects of public spaces in the way that contemporary humans see them. The gathered data is analysed and coded into spatial attributes from which their role in the complexity of open public space and measurability are discussed. The work results in an inventory of attributes that users find salient in public spaces. It does not discuss their qualitative values or contribution in generating spatial realities. It aims to define them clearly so that any further logical argumentation on open space concerning users may be solidly constructed. Finally, through categorisation of attributes it proposes the disciplinary levels necessary for the analysis of complex urban-architectural reality

  17. Open space suitability analysis for emergency shelter after an earthquake

    Directory of Open Access Journals (Sweden)

    J. Anhorn

    2014-06-01

    Full Text Available In an emergency situation shelter space is crucial for people affected by natural hazards. Emergency planners in disaster relief and mass care can greatly benefit from a sound methodology that identifies suitable shelter areas and sites where shelter services need to be improved. A methodology to rank suitability of open spaces for contingency planning and placement of shelter in the immediate aftermath of a disaster is introduced. The Open Space Suitability Index (OSSI uses the combination of two different measures: a qualitative evaluation criterion for the suitability and manageability of open spaces to be used as shelter sites, and a second quantitative criterion using a capacitated accessibility analysis based on network analysis. For the qualitative assessment, implementation issues, environmental considerations, and basic utility supply are the main categories to rank candidate shelter sites. Geographic Information System (GIS is used to reveal spatial patterns of shelter demand. Advantages and limitations of this method are discussed on the basis of a case study in Kathmandu Metropolitan City (KMC. According to the results, out of 410 open spaces under investigation, 12.2% have to be considered not suitable (Category D and E while 10.7% are Category A and 17.6% are Category B. Almost two third (59.5% are fairly suitable (Category C.

  18. A Global Space Control Strategy

    Science.gov (United States)

    2014-12-01

    Russia have sur- passed the post–Cold War taboos of talking about the development of space control activity with the announcement of the fielding of... searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send...and commercial entities seeking a benign environment. It is politically taboo to discuss space control events. Do- ing so runs the risk of creating

  19. Book Review: Opening Space Research: Dreams, Technology, and Scientific Discovery

    Science.gov (United States)

    Good, Gregory A.

    2012-05-01

    In Opening Space Research: Dreams, Technology, and Scientific Discovery, George Ludwig takes the reader behind the scenes of space exploration in the 1950s. The well-known episodes in this history—such as the stories of Sputnik, Laika the cosmodog, and the founding of NASA—are here placed in the rich context of the scientific and technical goals that motivated Ludwig and his fellow researchers. Ludwig relates the personal experiences of the many engineers, physicists, and university students who made possible humanity’s first ventures into space.

  20. A Discourse Approach to Theorising HRD: Opening a Discursive Space

    Science.gov (United States)

    Lawless, Aileen; Sambrook, Sally; Garavan, Tom; Valentin, Claire

    2011-01-01

    Purpose: The purpose of this paper is to discuss how a discourse approach to theorising human resource development (HRD) can open a "discursive space" to challenge dominant discourses within the field; enabling a more critical discourse to emerge. Design/methodology/approach: Discusses two approaches to discourse analysis, a "practice" and a…

  1. A Discourse Approach to Theorising HRD: Opening a Discursive Space

    Science.gov (United States)

    Lawless, Aileen; Sambrook, Sally; Garavan, Tom; Valentin, Claire

    2011-01-01

    Purpose: The purpose of this paper is to discuss how a discourse approach to theorising human resource development (HRD) can open a "discursive space" to challenge dominant discourses within the field; enabling a more critical discourse to emerge. Design/methodology/approach: Discusses two approaches to discourse analysis, a "practice" and a…

  2. Opening Spaces for Critical Literacy: Introducing Books to Young Readers

    Science.gov (United States)

    Labadie, Meredith; Wetzel, Melissa Mosley; Rogers, Rebecca

    2012-01-01

    How might book introductions open up spaces for critical literacy? This is the research question we asked while examining the records of teaching and learning within a yearlong teacher-research project in a second grade classroom. We designed a series of literacy units focused on themes of human rights, freedom, peace, and civil rights. Our focus…

  3. $\\gamma^{*}$-semi-open Sets in Topological Spaces-II

    CERN Document Server

    Hussain, Sabir

    2011-01-01

    In this paper, we continue studying the properties of $\\gamma^{*}$-semi-open sets in topological spaces introduced by S. Hussain, B. Ahmad and T. Noiri[8]. We also introduce and discuss the $\\gamma^{*}$-semi-continuous functions which generalize semi-continuous functions defined by N. Levine [10].

  4. Interactive human behavior analysis in open or public spaces

    NARCIS (Netherlands)

    Hung, H.; Odobez, J.M.; Gavrila, D.M.

    2011-01-01

    In the past years, efforts in surveillance and open space analysis have focused on traditional computer vision problems like scene modeling or object detection and tracking. Research on human behavior recognition have tended to work on predefined simple activities such as running, jumping or left lu

  5. An Open and Holistic Approach for Geo and Space Sciences

    Science.gov (United States)

    Ritschel, Bernd; Seelus, Christoph; Neher, Günther; Toshihiko, Iyemori; Yatagai, Akiyo; Koyama, Yukinobu; Murayama, Yasuhiro; King, Todd; Hughes, Steve; Fung, Shing; Galkin, Ivan; Hapgood, Mike; Belehaki, Anna

    2016-04-01

    Geo and space sciences thus far have been very successful, even often an open, cross-domain and holistic approach did not play an essential role. But this situation is changing rapidly. The research focus is shifting into more complex, non-linear and multi-domain specified phenomena, such as e.g. climate change or space environment. This kind of phenomena only can be understood step by step using the holistic idea. So, what is necessary for a successful cross-domain and holistic approach in geo and space sciences? Research and science in general become more and more dependent from a rich fundus of multi-domain data sources, related context information and the use of highly advanced technologies in data processing. Such buzzword phrases as Big Data and Deep Learning are reflecting this development. Big Data also addresses the real exponential growing of data and information produced by measurements or simulations. Deep Learning technology may help to detect new patterns and relationships in data describing high sophisticated natural phenomena. And further on, we should not forget science and humanities are only two sides of the same medal in the continuing human process of knowledge discovery. The concept of Open Data or in particular the open access to scientific data is addressing the free and open availability of -at least publicly founded and generated- data. The open availability of data covers the free use, reuse and redistribution of data which have been established with the formation of World Data Centers already more than 50 years ago. So, we should not forget, the foundation for open data is the responsibility of the individual scientist up until the big science institutions and organizations for a sustainable management of data. Other challenges are discovering and collecting the appropriate data, and preferably all of them or at least the majority of the right data. Therefore a network of individual or even better institutional catalog-based and at least

  6. Control of NASA's Space Launch System

    Science.gov (United States)

    VanZwieten, Tannen S.

    2014-01-01

    The flight control system for the NASA Space Launch System (SLS) employs a control architecture that evolved from Saturn, Shuttle & Ares I-X while also incorporating modern enhancements. This control system, baselined for the first unmanned launch, has been verified and successfully flight-tested on the Ares I-X rocket and an F/A-18 aircraft. The development of the launch vehicle itself came on the heels of the Space Shuttle retirement in 2011, and will deliver more payload to orbit and produce more thrust than any other vehicle, past or present, opening the way to new frontiers of space exploration as it carries the Orion crew vehicle, equipment, and experiments into new territories. The initial 70 metric ton vehicle consists of four RS-25 core stage engines from the Space Shuttle inventory, two 5- segment solid rocket boosters which are advanced versions of the Space Shuttle boosters, and a core stage that resembles the External Tank and carries the liquid propellant while also serving as the vehicle's structural backbone. Just above SLS' core stage is the Interim Cryogenic Propulsion Stage (ICPS), based upon the payload motor used by the Delta IV Evolved Expendable Launch Vehicle (EELV).

  7. Decomposition theorem in ideal topological spaces via a*-I-open sets and Asemi*-I-open sets

    Science.gov (United States)

    AL-Omeri, W.; Noorani, Mohd. Salmi.; AL-Omari, A.

    2014-09-01

    In this paper, we investigate some properties of a*-I-open set [3] and Asemi*-I-open sets defined in [3] in ideal topological space. The relationships of other related classes of sets are investigated. Also, a new decomposition of continuous functions is obtained by using δβA-I-open and SA*-set functions in an ideal topological space.

  8. Open Education as a Way for Space Education in Russia

    Science.gov (United States)

    Malyshev, V. V.; Karp, K. A.

    2002-01-01

    low level of state financial support. As a result there is a decreasing education quality. Scientific research was always an integral part of education and an alternative way for education financial support. But today the level of such support is too low as well. High experience of Russian space education system is not useful completely. This paper shows, that at present an open education could be a new step of space education in Russia. discussed in the paper. of students per one professor and also the number of students, which pay for education. New technology based on Internet technology would provide high methodology and technical level of education. The open education guarantees training in different areas and specialties on international standard level. education process, new education technology, new equipment of education system, new ways of financial support, international cooperation in education process, new professors and staffs in education system, increasing the level of salary for staff and comfortable conditions for students are discussed at the first. free education period, both traditional and new education methods are very important on the other side. about 4-5 years. The necessity of international educational system integration has to be taken into account. The international standard request, educational courses in different languages and free market conditions have to be under consideration. The partially ready open space education is discussed also. That system can be started even today.

  9. Open source software to control Bioflo bioreactors.

    Directory of Open Access Journals (Sweden)

    David A Burdge

    Full Text Available Bioreactors are designed to support highly controlled environments for growth of tissues, cell cultures or microbial cultures. A variety of bioreactors are commercially available, often including sophisticated software to enhance the functionality of the bioreactor. However, experiments that the bioreactor hardware can support, but that were not envisioned during the software design cannot be performed without developing custom software. In addition, support for third party or custom designed auxiliary hardware is often sparse or absent. This work presents flexible open source freeware for the control of bioreactors of the Bioflo product family. The functionality of the software includes setpoint control, data logging, and protocol execution. Auxiliary hardware can be easily integrated and controlled through an integrated plugin interface without altering existing software. Simple experimental protocols can be entered as a CSV scripting file, and a Python-based protocol execution model is included for more demanding conditional experimental control. The software was designed to be a more flexible and free open source alternative to the commercially available solution. The source code and various auxiliary hardware plugins are publicly available for download from https://github.com/LibourelLab/BiofloSoftware. In addition to the source code, the software was compiled and packaged as a self-installing file for 32 and 64 bit windows operating systems. The compiled software will be able to control a Bioflo system, and will not require the installation of LabVIEW.

  10. Open source software to control Bioflo bioreactors.

    Science.gov (United States)

    Burdge, David A; Libourel, Igor G L

    2014-01-01

    Bioreactors are designed to support highly controlled environments for growth of tissues, cell cultures or microbial cultures. A variety of bioreactors are commercially available, often including sophisticated software to enhance the functionality of the bioreactor. However, experiments that the bioreactor hardware can support, but that were not envisioned during the software design cannot be performed without developing custom software. In addition, support for third party or custom designed auxiliary hardware is often sparse or absent. This work presents flexible open source freeware for the control of bioreactors of the Bioflo product family. The functionality of the software includes setpoint control, data logging, and protocol execution. Auxiliary hardware can be easily integrated and controlled through an integrated plugin interface without altering existing software. Simple experimental protocols can be entered as a CSV scripting file, and a Python-based protocol execution model is included for more demanding conditional experimental control. The software was designed to be a more flexible and free open source alternative to the commercially available solution. The source code and various auxiliary hardware plugins are publicly available for download from https://github.com/LibourelLab/BiofloSoftware. In addition to the source code, the software was compiled and packaged as a self-installing file for 32 and 64 bit windows operating systems. The compiled software will be able to control a Bioflo system, and will not require the installation of LabVIEW.

  11. Generalizations of γ-open set in topological spaces

    Science.gov (United States)

    Bhattacharya, Baby; Paul, Arnab

    2016-06-01

    The main aim of this work is to study three generalized forms of γ-open set due to D. Andrijevic (D. Andrijevic, On the Topology Generated by pre-open sets, Presented at the Sixth Prague Topological Symposium, 39 (1987), 367-376)in a topological space. Out of which the dual appearance of one is the stronger form of b-locally closed set in the sense of Arafa A. Nasef (A. A Nasef,On b-locally closed sets and related topics, CHAOS SOLITONS & FRACTALS 12(2001) 1909-1915). Also, we introduce the concept of different types of continuity and study their basic properties by using these newly defined sets. Finally, we establish the interrelationships among themselves together with some already existing generalized forms of continuity.

  12. Linguistic Landscape and Space: A Multimodal Analysis of Linguistic landscape in Robot Open Space

    Directory of Open Access Journals (Sweden)

    Song Chen

    2016-11-01

    Full Text Available The paper examines the linguistic landscape in an indoor public place, Robot Open Space in Zhongguancun Dream Laboratory, which is a building housing a handful of innovative entrepreneurial enterprises. The subject of analysis in this present paper is the impact of different spaces on the features of linguistic landscape. Each of the three major sub-spaces in the company Robot Open Space has different functions and the linguistic landscape with its different features varies accordingly. This present study has the following contributions. First, the shift of analytical attention from the outdoor linguistic landscape to the indoor linguistic landscape provides a new angle for LL analysis and further expands the scenery of linguistic landscape. Then, the newly establish analytical framework, the “multimodal model for linguistic landscape analysis” enrich the current theoretical models that is quite rare. Last, the qualitative analysis of the linguistic landscapes in different spaces shed light on the correlation between space and linguistic landscape, indicating that space is an integral factor to be considered when it comes to LL analysis.Keywords: linguistic landscape; multimodal model; qualitative analysis; space

  13. Hybrid open public space of landscape elements and built structure

    Directory of Open Access Journals (Sweden)

    Gordana Bence

    2008-01-01

    Full Text Available The trend today in the cities in Europe and elsewhere is in combining landscape elements, built structure and different uses into a complex urban structure. Physical and program interweaving of landscape elements and built structure enables the consumers daily practice of leisure programs – relaxation, recreation and experiencing other cultural, educational and social events in the public green space. On the basis of determinate social changes and new approaches in urban planning practice, analyses of architectural and urban case studies from the point of view of integrating the landscape elements into the urban structure, the article defines the phenomenon of hybrid open public space and proposes methodical guidelines for the planning.

  14. Global Positioning System-Based Stimulation for Robo-Pigeons in Open Space

    Directory of Open Access Journals (Sweden)

    Junqing Yang

    2017-08-01

    Full Text Available An evaluation method is described that will enable researchers to study fight control characteristics of robo-pigeons in fully open space. It is not limited by the experimental environment and overcomes environmental interference with flight control in small experimental spaces using a compact system. The system consists of two components: a global positioning system (GPS-based stimulator with dimensions of 38 mm × 26 mm × 8 mm and a weight of 18 g that can easily be carried by a pigeon as a backpack and a PC-based program developed in Virtual C++. The GPS-based stimulator generates variable stimulation and automatically records the GPS data and stimulus parameters. The PC-based program analyzes the recorded data and displays the flight trajectory of the tested robo-pigeon on a digital map. This method enables quick and clear evaluation of the flight control characteristics of a robo-pigeon in open space based on its visual trajectory, as well as further optimization of the microelectric stimulation parameters to improve the design of robo-pigeons. The functional effectiveness of the method was investigated and verified by performing flight control experiments using a robo-pigeon in open space.

  15. Economic analysis of open space box model utilization in spacecraft

    Science.gov (United States)

    Mohammad, Atif F.; Straub, Jeremy

    2015-05-01

    It is a known fact that the amount of data about space that is stored is getting larger on an everyday basis. However, the utilization of Big Data and related tools to perform ETL (Extract, Transform and Load) applications will soon be pervasive in the space sciences. We have entered in a crucial time where using Big Data can be the difference (for terrestrial applications) between organizations underperforming and outperforming their peers. The same is true for NASA and other space agencies, as well as for individual missions and the highly-competitive process of mission data analysis and publication. In most industries, conventional opponents and new candidates alike will influence data-driven approaches to revolutionize and capture the value of Big Data archives. The Open Space Box Model is poised to take the proverbial "giant leap", as it provides autonomic data processing and communications for spacecraft. We can find economic value generated from such use of data processing in our earthly organizations in every sector, such as healthcare, retail. We also can easily find retailers, performing research on Big Data, by utilizing sensors driven embedded data in products within their stores and warehouses to determine how these products are actually used in the real world.

  16. OMAC4S- Open Modular Avionics for Space Applications

    Science.gov (United States)

    Herpel, H.-J.; Willich, G.; Vogel, T.; Schuettauf, A.; Pletner, S.; Schoen, F.; Fidi, C.; Loetzke, M.; Dittrich, L.; Schuelke, P.; Wolf, T.

    2013-08-01

    Today's spacecraft avionics architecture is characterised by a broad variety of processing modules, operating systems and interfaces for exchanging data between different processing modules. The software that implements most of the satellite functionality has to deal with this fact and is one of the reasons why software has become one of the major cost drivers in satellite projects. Similar problems have triggered developments in other industrial domains like AUTOSAR in the automotive area or Integrated Modular Architecture (IMA) in the aerospace industry [8]. All these initiatives are based on the definition of standards for computing platforms and the interfaces between these platforms. The goals of the Open Modular Avionics Architecture for Space Applications (OMAC4S) initiative started by Astrium, Fraunhofer FOKUS, STI, SYSGO and TTTech are to outline a solution that helps to reduce complexity and costs for space avionics significantly. This initiative is partly funded by the German national space agency (DLR) through the project On-Board Computer System Architecture (OBC-SA). In this paper we describe how standardization and the usage of already proven technologies from other industrial domains will help to limit the effect of the software development on schedule and costs of satellite projects. In addition we will demonstrate a migration path to make these technologies available for space applications.

  17. Personal Spaces in Public Repositories as a Facilitator for Open Educational Resource Usage

    Science.gov (United States)

    Cohen, Anat; Reisman, Sorel; Sperling, Barbra Bied

    2015-01-01

    Learning object repositories are a shared, open and public space; however, the possibility and ability of personal expression in an open, global, public space is crucial. The aim of this study is to explore personal spaces in a big learning object repository as a facilitator for adoption of Open Educational Resources (OER) into teaching practices…

  18. Public evaluation of open space in Illinois: citizen support for natural area acquisition.

    Science.gov (United States)

    Backlund, Erik A; Stewart, William P; McDonald, Cary; Miller, Craig

    2004-11-01

    Numerous studies have indicated a broad-based support for open space preservation and protection. Research also has characterized the public values and rationale that underlie the widespread support for open space. In recognition of the widespread public support for open space, various levels of government have implemented programs to provide public access to open space. There are many different types of open space, ranging from golf courses, ball parks, wildlife areas, and prairies, to name a few. This paper addresses questions related to the types of open space that should be prioritized by planners and natural resource managers. The results of this study are based on a stratified random sample of 5000 households in Illinois that were sent a questionnaire related to their support for various types of open space. Through a comparatively simple action grid analysis, the open space types that should be prioritized for public access include forest areas, stream corridors, wildlife habitat, and lakes/ponds. These were the open space types rated of the highest importance, yet were also the open space types rated the lowest in respondent satisfaction. This kind of analysis does not require the technical expertise of other options for land-use prioritizations (e.g., conjoint analysis, contingent valuation), yet provides important policy directives for planners. Although open space funds often allow for purchase of developed sites such as golf courses, ball parks, and community parks, this study indicates that undeveloped (or nature-based) open space lands are most needed in Illinois.

  19. Controllability of open quantum systems with Kraus-map dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Wu Rong; Pechen, Alexander; Brif, Constantin; Rabitz, Herschel [Department of Chemistry, Princeton University, Princeton, NJ 08544 (United States)

    2007-05-25

    This paper presents a constructive proof of complete kinematic state controllability of finite-dimensional open quantum systems whose dynamics are represented by Kraus maps. For any pair of states (pure or mixed) on the Hilbert space of the system, we explicitly show how to construct a Kraus map that transforms one state into another. Moreover, we prove by construction the existence of a Kraus map that transforms all initial states into a predefined target state (such a process may be used, for example, in quantum information dilution). Thus, in sharp contrast to unitary control, Kraus-map dynamics allows for the design of controls which are robust to variations in the initial state of the system. The capabilities of non-unitary control for population transfer between pure states illustrated for an example of a two-level system by constructing a family of non-unitary Kraus maps to transform one pure state into another. The problem of dynamic state controllability of open quantum systems (i.e., controllability of state-to-state transformations, given a set of available dynamical resources such as coherent controls, incoherent interactions with the environment, and measurements) is also discussed.

  20. Task-space sensory feedback control of robot manipulators

    CERN Document Server

    Cheah, Chien Chern

    2015-01-01

    This book presents recent advances in robot control theory on task space sensory feedback control of robot manipulators. By using sensory feedback information, the robot control systems are robust to various uncertainties in modelling and calibration errors of the sensors. Several sensory task space control methods that do not require exact knowledge of either kinematics or dynamics of robots, are presented. Some useful methods such as approximate Jacobian control, adaptive Jacobian control, region control and multiple task space regional feedback are included. These formulations and methods give robots a high degree of flexibility in dealing with unforeseen changes and uncertainties in its kinematics and dynamics, which is similar to human reaching movements and tool manipulation. It also leads to the solution of several long-standing problems and open issues in robot control, such as force control with constraint uncertainty, control of multi-fingered robot hand with uncertain contact points, singularity i...

  1. Nonlinear Control of an Open-Loop Open-Winding Motor System with Modulated Converters

    Directory of Open Access Journals (Sweden)

    Oleschuk V.I.

    2017-04-01

    Full Text Available Purpose of this work - to provide wider control opportunities for multiphase open-end winding motor drive by modification of basic scheme of space-vector pulse-width modulation (PWM. It has been shown, that the proposed development of basic PWM scheme insures available solutions for realization of specific control dependences and modes of operation of adjustable speed ac drives with different types and kinds of loads. Suitable algorithms of PWM of converters of multiphase drive have been analyzed and compared. Extensive simulation studies have been executed for evaluation of performance and effectiveness of the proposed control strategy. Assessment of harmonic composition of the phase voltages of drive system with modified scheme of space-vector modulation has been done. Results of the executed simulations proved the fact, that the developed techniques of space-vector pulse-width modulation allow providing quarter-wave or half-wave symmetry of waveforms of the output voltage of six-phase adjustable speed drive systems during the analyzed non-standard modes and regimes of its operation.

  2. Open Space Box: communication to support Big Data in orbit

    Science.gov (United States)

    Mohammad, Atif F.; Straub, Jeremy

    2015-05-01

    Communication to and from a small spacecraft can be at an extremely slow Baud rate, means both sending and receiving any communication will take some time. Extract, Transform and Load tools designed to transmit and receive data needs to have a flexible protocol. The Open Space Box model provides this base for smaller spacecraft to provide users data in a fashion that is pervasive within satellites as well as the ground stations. It also autonomically distinguishes data streams and disseminates relevant information to the related end users. Streaming Data can also be considered the generation of Big Data. At a ground station, the receiving of data can create the problem of Big Data and its management. Messages are sent in batch mode and communications are done using MapReduce.

  3. Spotting East African mammals in open savannah from space.

    Directory of Open Access Journals (Sweden)

    Zheng Yang

    Full Text Available Knowledge of population dynamics is essential for managing and conserving wildlife. Traditional methods of counting wild animals such as aerial survey or ground counts not only disturb animals, but also can be labour intensive and costly. New, commercially available very high-resolution satellite images offer great potential for accurate estimates of animal abundance over large open areas. However, little research has been conducted in the area of satellite-aided wildlife census, although computer processing speeds and image analysis algorithms have vastly improved. This paper explores the possibility of detecting large animals in the open savannah of Maasai Mara National Reserve, Kenya from very high-resolution GeoEye-1 satellite images. A hybrid image classification method was employed for this specific purpose by incorporating the advantages of both pixel-based and object-based image classification approaches. This was performed in two steps: firstly, a pixel-based image classification method, i.e., artificial neural network was applied to classify potential targets with similar spectral reflectance at pixel level; and then an object-based image classification method was used to further differentiate animal targets from the surrounding landscapes through the applications of expert knowledge. As a result, the large animals in two pilot study areas were successfully detected with an average count error of 8.2%, omission error of 6.6% and commission error of 13.7%. The results of the study show for the first time that it is feasible to perform automated detection and counting of large wild animals in open savannahs from space, and therefore provide a complementary and alternative approach to the conventional wildlife survey techniques.

  4. Control of rock joint parameters on deformation of tunnel opening

    Institute of Scientific and Technical Information of China (English)

    Suman Panthee; P.K. Singh; Ashutosh Kainthola; T.N. Singh

    2016-01-01

    Tunneling in complex rock mass conditions is a challenging task, especially in the Himalayan terrain, where a number of unpredicted conditions are reported. Rock joint parameters such as persistence, spacing and shear strength are the factors which significantly modify the working environments in the vicinity of the openings. Therefore, a detailed tunnel stability assessment is critically important based on the field data collection on the excavated tunnel’s face. In this context, intact as well as rock mass strength and defor-mation modulus is obtained from laboratory tests for each rock type encountered in the study area. Finite element method (FEM) is used for stability analysis purpose by parametrically varying rock joint persis-tence, spacing and shear strength parameters, until the condition of overbreak is reached. Another case of marginally stable condition is also obtained based on the same parameters. The results show that stability of tunnels is highly influenced by these parameters and the size of overbreak is controlled by joint persistence and spacing. Garnetiferous schist and slate characterized using high persistence show the development of large plastic zones but small block size, depending upon joint spacing; whereas low persistence, low spacing and low shear strength in marble and quartzite create rock block fall condition.

  5. 21 CFR 11.30 - Controls for open systems.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Controls for open systems. 11.30 Section 11.30... RECORDS; ELECTRONIC SIGNATURES Electronic Records § 11.30 Controls for open systems. Persons who use open systems to create, modify, maintain, or transmit electronic records shall employ procedures and...

  6. Access control mechanism of wireless gateway based on open flow

    Science.gov (United States)

    Peng, Rong; Ding, Lei

    2017-08-01

    In order to realize the access control of wireless gateway and improve the access control of wireless gateway devices, an access control mechanism of SDN architecture which is based on Open vSwitch is proposed. The mechanism utilizes the features of the controller--centralized control and programmable. Controller send access control flow table based on the business logic. Open vSwitch helps achieve a specific access control strategy based on the flow table.

  7. SATA Controller Into a Space CPU

    Science.gov (United States)

    De Nino, M.; Titomanlio, D.; Calvanese, R.; Capuano, G.; Rovatti, M.

    2014-08-01

    This paper is dedicated to the presentation of a project, funded by ESA, named "SATA Controller into a Space CPU" aimed at starting a development activity to spin- in the SATA technology to the space market.Space applications could benefit from the adoption of the SATA protocol as interface layer between the host controller and the mass memory module. Currently no space-proven implementation of the SATA specification exists.

  8. Autonomous Control of Space Nuclear Reactors Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Nuclear reactors to support future robotic and manned missions impose new and innovative technological requirements for their control and protection instrumentation....

  9. Cesium Diffusion through Angstrom-Scale Open Spaces in Clay Minerals

    Science.gov (United States)

    Fujimoto, Koichiro; Sato, Kiminori; Nakata, Masataka

    2017-03-01

    Saponite clay minerals possess the local molecular structures, where one and two nanosheets are inserted into interlayer spaces forming open spaces with their sizes of ˜3 and ˜9 Å, respectively. Here, Cs diffusion via the above-mentioned open spaces is highlighted based on the results of open space analysis using positronium (Ps) lifetime spectroscopy coupled with a conventional diffusion experiment. A population of Cs is found to significantly migrate in the saponite clay yielding a diffusion coefficient of ˜2.0 × 10-7 cm2 s-1 with an application of Fick's second law, which arises from overall diffusion contributed from open spaces with a variety of sizes. On the other hand, the diffusion coefficient solely attributable to the angstrom-scale open space is ˜2.5 × 10-8 cm2 s-1, which amounts to more than ˜10% than that of overall diffusion.

  10. Public open space, physical activity, urban design and public health: Concepts, methods and research agenda.

    Science.gov (United States)

    Koohsari, Mohammad Javad; Mavoa, Suzanne; Villanueva, Karen; Sugiyama, Takemi; Badland, Hannah; Kaczynski, Andrew T; Owen, Neville; Giles-Corti, Billie

    2015-05-01

    Public open spaces such as parks and green spaces are key built environment elements within neighbourhoods for encouraging a variety of physical activity behaviours. Over the past decade, there has been a burgeoning number of active living research studies examining the influence of public open space on physical activity. However, the evidence shows mixed associations between different aspects of public open space (e.g., proximity, size, quality) and physical activity. These inconsistencies hinder the development of specific evidence-based guidelines for urban designers and policy-makers for (re)designing public open space to encourage physical activity. This paper aims to move this research agenda forward, by identifying key conceptual and methodological issues that may contribute to inconsistencies in research examining relations between public open space and physical activity.

  11. A hybrid approach to space power control

    Science.gov (United States)

    Gholdston, E. W.; Janik, D. F.; Newton, K. A.

    1990-01-01

    Conventional control systems have traditionally been utilized for space-based power designs. However, the use of expert systems is becoming important for NASA applications. Rocketdyne has been pursuing the development of expert systems to aid and enhance control designs of space-based power systems. The need for integrated expert systems is vital for the development of autonomous power systems.

  12. Portable Low-Frequency Noise Reduction Device for Both Small Open and Closed Spaces

    Directory of Open Access Journals (Sweden)

    Chao Wang

    2016-01-01

    Full Text Available Noise pollution has been given more attention due to its negative impacts on human health and disease. The portable low-frequency noise reduction device we developed in this research can provide an effective way for solving low-frequency noise pollution problem in the small space. This work describes the design principle and the prototype structures for two versions of V1.5 and V2.0 and builds the noise test systems for small spaces, respectively. These devices, installed on the outer surface of the small spaces, can automatically identify the noise spectrum and implement noise reduction by means of the active noise control (ANC technology. The testing results indicate that the noise can be reduced 12 dB in the range of 250 Hz~400 Hz for the small closed space while, for the small open space, the best effect of 5.88 dB occurs in the optimal frequency of 450 Hz. These effects will be weakened with the increasing distance away from the source and show the obvious axisymmetric distribution in the inverted cone space.

  13. The value of urban open space: meta-analyses of contingent valuation and hedonic pricing results.

    Science.gov (United States)

    Brander, Luke M; Koetse, Mark J

    2011-10-01

    Urban open space provides a number of valuable services to urban populations, including recreational opportunities, aesthetic enjoyment, environmental functions, and may also be associated with existence values. In separate meta-analyses of the contingent valuation (CV) and hedonic pricing (HP) literature we examine which physical, socio-economic, and study characteristics determine the value of open space. The dependent variable in the CV meta-regression is defined as the value of open space per hectare per year in 2003 US$, and in the HP model as the percentage change in house price for a 10 m decrease in distance to open space. Using a multi-level modelling approach we find in both the CV and HP analyses that there is a positive and significant relationship between the value of urban open space and population density, indicating that scarcity and crowdedness matter, and that the value of open space does not vary significantly with income. Further, urban parks are more highly valued than other types of urban open space (forests, agricultural and undeveloped land) and methodological differences in study design have a large influence on estimated values from both CV and HP. We also find important regional differences in preferences for urban open space, which suggests that the potential for transferring estimated values between regions is likely to be limited. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Quantum Control of Open Systems and Dense Atomic Ensembles

    Science.gov (United States)

    DiLoreto, Christopher

    Controlling the dynamics of open quantum systems; i.e. quantum systems that decohere because of interactions with the environment, is an active area of research with many applications in quantum optics and quantum computation. My thesis expands the scope of this inquiry by seeking to control open systems in proximity to an additional system. The latter could be a classical system such as metal nanoparticles, or a quantum system such as a cluster of similar atoms. By modelling the interactions between the systems, we are able to expand the accessible state space of the quantum system in question. For a single, three-level quantum system, I examine isolated systems that have only normal spontaneous emission. I then show that intensity-intensity correlation spectra, which depend directly on the density matrix of the system, can be used detect whether transitions share a common energy level. This detection is possible due to the presence of quantum interference effects between two transitions if they are connected. This effect allows one to asses energy level structure diagrams in complex atoms/molecules. By placing an open quantum system near a nanoparticle dimer, I show that the spontaneous emission rate of the system can be changed "on demand" by changing the polarization of an incident, driving field. In a three-level, Lambda system, this allows a qubit to both retain high qubit fidelity when it is operating, and to be rapidly initialized to a pure state once it is rendered unusable by decoherence. This type of behaviour is not possible in a single open quantum system; therefore adding a classical system nearby extends the overall control space of the quantum system. An open quantum system near identical neighbours in a dense ensemble is another example of how the accessible state space can be expanded. I show that a dense ensemble of atoms rapidly becomes disordered with states that are not directly excited by an incident field becoming significantly populated

  15. An Urban Open Space Extraction Method:Combining Spectral and Geometric Characteristics

    Institute of Scientific and Technical Information of China (English)

    ZHU Guobin; Dan G. Blumberg

    2004-01-01

    This paper introduces an advanced method based on remote sensing and Geographic Information System for urban open space extraction combining spectral and geometric characteristics. From both semantic and remote sensing perspectives, a hybrid hierarchy structure and class organization of open space are issues and mapped from one to another. Based on per-pixel and segmentation mechanism separately, two classification approaches are performed. Owing to prior of spatial aggregation and spectral contribution, the segmentation-based classification exhibits its superiority over a pixel-based classification. Finally a GIS-based post procedure is hired to eliminate some unsuitable open space components in both spatial and numerical constraints on the one hand, and separate open space some fabrics from fused remote sensing classes by defining their Shape Index on the other hand. The case study of Beer Sheva based on ASTER data proves this method is a feasible way for open space extraction.

  16. Gauge Theories on Open Lie Algebra Noncommutative Spaces

    Science.gov (United States)

    Agarwal, A.; Akant, L.

    It is shown that noncommutative spaces, which are quotients of associative algebras by ideals generated by highly nonlinear relations of a particular type, admit extremely simple formulae for deformed or star products. Explicit construction of these star products is carried out. Quantum gauge theories are formulated on these spaces, and the Seiberg-Witten map is worked out in detail.

  17. Open Problem: Kernel methods on manifolds and metric spaces

    DEFF Research Database (Denmark)

    Feragen, Aasa; Hauberg, Søren

    2016-01-01

    Radial kernels are well-suited for machine learning over general geodesic metric spaces, where pairwise distances are often the only computable quantity available. We have recently shown that geodesic exponential kernels are only positive definite for all bandwidths when the input space has strong...

  18. Open Data and Open Science for better Research in the Geo and Space Domain

    Science.gov (United States)

    Ritschel, B.; Seelus, C.; Neher, G.; Iyemori, T.; Koyama, Y.; Yatagai, A. I.; Murayama, Y.; King, T. A.; Hughes, S.; Fung, S. F.; Galkin, I. A.; Hapgood, M. A.; Belehaki, A.

    2015-12-01

    Main open data principles had been worked out in the run-up and finally adopted in the Open Data Charta at the G8 summit in Lough Erne, Northern Ireland in June 2013. Important principles are also valid for science data, such as Open Data by Default, Quality and Quantity, Useable by All, Releasing Data for Improved Governance, Releasing Data for Innovation. There is also an explicit relationship to such areas of high values as earth observation, education and geospatial data. The European union implementation plan of the Open Data Charta identifies among other things objectives such as making data available in an open format, enabling semantic interoperability, ensuring quality, documentation and where appropriate reconciliation across different data sources, implementing software solutionsallowing easy management, publication or visualization of datasets and simplifying clearance of intellectual property rights.Open Science is not just a list of already for a longer time known principles but stands for a lot of initiatives and projects around a better handling of scientific data and openly shared scientific knowledge. It is also about transparency in methodology and collection of data, availability and reuse of scientific data, public accessibility to scientific communication and using of social media to facility scientific collaboration. Some projects are concentrating on open sharing of free and open source software and even further hardware in kind of processing capabilities. In addition question about the mashup of data and publication and an open peer review process are addressed.Following the principles of open data and open science the newest results of the collaboration efforts in mashing up the data servers related to the Japanese IUGONET, the European Union ESPAS and the GFZ ISDC semantic Web projects will be presented here. The semantic Web based approach for the mashup is focusing on the design and implementation of a common but still distributed data

  19. 75 FR 54002 - Commercial Space Transportation Advisory Committee-Open Meeting

    Science.gov (United States)

    2010-09-02

    ... Federal Aviation Administration Commercial Space Transportation Advisory Committee--Open Meeting AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Commercial Space Transportation Advisory.... 92-463, 5 U.S.C. App. 2), notice is hereby given of a meeting of the Commercial Space...

  20. 77 FR 16891 - Commercial Space Transportation Advisory Committee-Open Meeting

    Science.gov (United States)

    2012-03-22

    ... Federal Aviation Administration Commercial Space Transportation Advisory Committee--Open Meeting AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Commercial Space Transportation Advisory.... 92-463, 5 U.S.C. App. 2), notice is hereby given of a meeting of the Commercial Space...

  1. 76 FR 17474 - Commercial Space Transportation Advisory Committee-Open Meeting

    Science.gov (United States)

    2011-03-29

    ... Federal Aviation Administration Commercial Space Transportation Advisory Committee--Open Meeting AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Commercial Space Transportation Advisory.... 92-463, 5 U.S.C. App. 2), notice is hereby given of a meeting of the Commercial Space...

  2. 78 FR 69742 - Commercial Space Transportation Advisory Committee-Open Meeting

    Science.gov (United States)

    2013-11-20

    ... Federal Aviation Administration Commercial Space Transportation Advisory Committee--Open Meeting AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Commercial Space Transportation Advisory.... 92-463, 5 U.S.C. App. 2), notice is hereby given of a meeting of the Commercial Space...

  3. Autonomous Control of Space Nuclear Reactors Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Nuclear reactors to support future lunar and Mars robotic and manned missions impose new and innovative technological requirements for their control and protection...

  4. Next Generation Space Interconnect Standard (NGSIS): a modular open standards approach for high performance interconnects for space

    Science.gov (United States)

    Collier, Charles Patrick

    2017-04-01

    The Next Generation Space Interconnect Standard (NGSIS) effort is a Government-Industry collaboration effort to define a set of standards for interconnects between space system components with the goal of cost effectively removing bandwidth as a constraint for future space systems. The NGSIS team has selected the ANSI/VITA 65 OpenVPXTM standard family for the physical baseline. The RapidIO protocol has been selected as the basis for the digital data transport. The NGSIS standards are developed to provide sufficient flexibility to enable users to implement a variety of system configurations, while meeting goals for interoperability and robustness for space. The NGSIS approach and effort represents a radical departure from past approaches to achieve a Modular Open System Architecture (MOSA) for space systems and serves as an exemplar for the civil, commercial, and military Space communities as well as a broader high reliability terrestrial market.

  5. Analysis of Cisco Open Network Environment (ONE) OpenFlow Controller Implementation

    Science.gov (United States)

    2014-08-01

    or match criteria to ports that are not connected) as well as the ability to install and uninstall a flow from switches without deleting it entirely...Port recognition Not explicit Yes Install/ uninstall flows NA Yes Set dynamic flows Requires code manipulation Yes 6 5.2 OpenFlow Control Channel...Setup The initial handshake between the controller and switch was monitored using packet analysis tools capable of understanding OpenFlow protocol

  6. Remaking Nigeria’s Urbanism: Assessing and Redressing the Dearth of Open Spaces in Benin City

    Directory of Open Access Journals (Sweden)

    Ndubisi Onwuanyi

    2017-05-01

    Full Text Available Unplanned land use in most Nigerian cities has meant that all urban land needs are not adequately provided for within their landscapes. Open spaces are either conspicuously missing or inadequate. There is a tendency for existing open spaces to be lost to urban development pressure and a disregard for zoning. This paper identifies available and accessible open spaces in Benin City and assesses their adequacy using as a guide standards established in two selected international jurisdictions, discusses the potential benefits of open space to the city on the one hand and its residents on the other given the incipient impacts of global warming and climate change, and the prospects of mitigation by greening the city even in its already built-up state. Data is sourced from journals, reports, archival records and inspections of the urban environment. The findings confirm a great dearth of open spaces as well as deteriorating urban environmental conditions which have implications for health, well-being and urban sustainability. The recommendations are that future expansions of the city space incorporate adequate provisions for open spaces, whilst within the existing built-up city, solutions be sought in the creation of greenways, green paths, private green spaces, promoting street trees and the conversion of brownfield sites to green areas.

  7. Exploring Open-Ended Design Space of Mechatronic Systems

    DEFF Research Database (Denmark)

    Fan, Zhun; Wang, J.; Goodman, E.

    2004-01-01

    To realize design automation of mechatronic systems, there are two major issues to be dealt with: open-topology generation of mechatronic systems and simulation or analysis of those models. For the first issue, we exploit the strong topology exploration capability of genetic programming to create...

  8. Open-Space Lab Provides Data on a New Concept

    Science.gov (United States)

    Kreamer, Ralph

    1972-01-01

    Describes the Jenkins Elementary School which not only serves as a neighborhood elementary education facility, but also provides students at Millersville State College, Pennsylvania, an opportunity to learn, work with, and observe the many different concepts embodied in open education. (Author/MB)

  9. Open standards for unattended sensors (OSUS) power managed controller

    Science.gov (United States)

    Rohrer, Matt; Porter, Rich; Fish, Robert; Knobler, Ron

    2014-06-01

    The Open Standards for Unattended Sensors (OSUS) program, formerly named Terra Harvest, was launched in 2009 to develop an open, integrated battlefield unattended ground sensors (UGS) architecture that ensures interoperability among disparate UGS components and systems. McQ has developed a power managed controller, which is a rugged fielded device that runs an embedded Linux operating system using an open Java software architecture, runs for over 30 days on a small battery pack, and provides various critical functions including the required management, monitoring, and control functions. The OSUS power managed controller system overview, design, and compatibility with other systems will be discussed.

  10. Auditory Perception in an Open Space: Detection and Recognition

    Science.gov (United States)

    2015-06-01

    line of sight provides attenuation of about 5 dB or more across most of the auditory frequency range, and higher barriers can attenuate sound by as much...distance estimation to, various sound sources spread across a large open field. This report presents results of the detection and recognition tasks. Both...acoustic (target sound and noise level) and meteorological (wind direction and strength, temperature, atmospheric pressure, humidity) data were

  11. Space Application for ITMA ASIA + CITME 2010 Exhibition Opens

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    @@ 28 April 2009 - Leading textile machinery manufacturers from around the world are invited to apply for space at the second combined ITMA ASIA + CITME exhibition to be held at the Shanghai New International Expo Cen-tre from 22 to 26 June 2010.

  12. Homology of the open moduli space of curves

    DEFF Research Database (Denmark)

    Madsen, Ib Henning

    2012-01-01

    This is a survey on the proof of a generalized version of the Mumford conjecture obtained in joint work with M. Weiss stating that a certain map between some classifying spaces which a priori have different natures induces an isomorphism at the level of integral homology. We also discuss our proof...

  13. Modular reconfigurable machines incorporating modular open architecture control

    CSIR Research Space (South Africa)

    Padayachee, J

    2008-01-01

    Full Text Available degrees of freedom on a single platform. A corresponding modular Open Architecture Control (OAC) system is presented. OAC overcomes the inflexibility of fixed proprietary automation, ensuring that MRMs provide the reconfigurability and extensibility...

  14. Autonomous Control of Space Reactor Systems

    Energy Technology Data Exchange (ETDEWEB)

    Belle R. Upadhyaya; K. Zhao; S.R.P. Perillo; Xiaojia Xu; M.G. Na

    2007-11-30

    Autonomous and semi-autonomous control is a key element of space reactor design in order to meet the mission requirements of safety, reliability, survivability, and life expectancy. Interrestrial nuclear power plants, human operators are avilable to perform intelligent control functions that are necessary for both normal and abnormal operational conditions.

  15. Distribution of green open space in Malang City based on multispectral data

    Science.gov (United States)

    Hasyim, A. W.; Hernawan, F. P.

    2017-06-01

    Green open space is one of the land that its existence is quite important in urban areas where the minimum area is set to reach 30% of the total area of the city. Malang which has an area of 110,6 square kilometers, is one of the major cities in East Java Province that is prone to over-land conversion due to development needs. In support of the green space program, calculation of green space is needed precisely so that remote sensing which has high accuracy is now used for measurement of green space. This study aims to analyze the area of green open space in Malang by using Landsat 8 image in 2015. The method used was the vegetation index that is Normalized Difference Vegetation Index (NDVI). From the study obtained the calculation of green open space was better to use the vegetation index method to avoid the occurrence of misclassification of other types of land use. The results of the calculation of green open space using NDVI found that the area of green open space in Malang City in 2015 reached 39% of the total area.

  16. Open string fluctuations in AdS space with and without torsion

    DEFF Research Database (Denmark)

    Larsen, A.L.; Lomholt, Michael Andersen

    2003-01-01

    The equations of motion and boundary conditions for the fluctuations around a classical open string, in a curved space-time with torsion, are considered in compact and world-sheet covariant form. The rigidly rotating open strings in anti-de Sitter space with and without torsion are investigated i...... dangerous than expected in these cases. The general formalism can be straightforwardly used also to study the (bosonic part of the) fluctuations around the closed strings, recently considered in connection with the AdS/conformal field theory duality, on AdS ×S and AdS ×S ×T .......The equations of motion and boundary conditions for the fluctuations around a classical open string, in a curved space-time with torsion, are considered in compact and world-sheet covariant form. The rigidly rotating open strings in anti-de Sitter space with and without torsion are investigated...

  17. Automatic Open Space Area Extraction and Change Detection from High Resolution Urban Satellite Images

    CERN Document Server

    Kodge, B G

    2011-01-01

    In this paper, we study efficient and reliable automatic extraction algorithm to find out the open space area from the high resolution urban satellite imagery, and to detect changes from the extracted open space area during the period 2003, 2006 and 2008. This automatic extraction and change detection algorithm uses some filters, segmentation and grouping that are applied on satellite images. The resultant images may be used to calculate the total available open space area and the built up area. It may also be used to compare the difference between present and past open space area using historical urban satellite images of that same projection, which is an important geo spatial data management application.

  18. Adaptive Power Control for Space Communications

    Science.gov (United States)

    Thompson, Willie L., II; Israel, David J.

    2008-01-01

    This paper investigates the implementation of power control techniques for crosslinks communications during a rendezvous scenario of the Crew Exploration Vehicle (CEV) and the Lunar Surface Access Module (LSAM). During the rendezvous, NASA requires that the CEV supports two communication links: space-to-ground and crosslink simultaneously. The crosslink will generate excess interference to the space-to-ground link as the distances between the two vehicles decreases, if the output power is fixed and optimized for the worst-case link analysis at the maximum distance range. As a result, power control is required to maintain the optimal power level for the crosslink without interfering with the space-to-ground link. A proof-of-concept will be described and implemented with Goddard Space Flight Center (GSFC) Communications, Standard, and Technology Lab (CSTL).

  19. Open Hardware For CERN's Accelerator Control Systems

    CERN Document Server

    van der Bij, E; Ayass, M; Boccardi, A; Cattin, M; Gil Soriano, C; Gousiou, E; Iglesias Gonsálvez, S; Penacoba Fernandez, G; Serrano, J; Voumard, N; Wlostowski, T

    2011-01-01

    The accelerator control systems at CERN will be renovated and many electronics modules will be redesigned as the modules they will replace cannot be bought anymore or use obsolete components. The modules used in the control systems are diverse: analog and digital I/O, level converters and repeaters, serial links and timing modules. Overall around 120 modules are supported that are used in systems such as beam instrumentation, cryogenics and power converters. Only a small percentage of the currently used modules are commercially available, while most of them had been specifically designed at CERN. The new developments are based on VITA and PCI-SIG standards such as FMC (FPGA Mezzanine Card), PCI Express and VME64x using transition modules. As system-on-chip interconnect, the public domain Wishbone specification is used. For the renovation, it is considered imperative to have for each board access to the full hardware design and its firmware so that problems could quickly be resolved by CERN engineers or its ...

  20. On some classes of nearly open sets in nano topological spaces

    Directory of Open Access Journals (Sweden)

    A.  A. Nasef

    2016-10-01

    Full Text Available One of the aims of this paper is to study some near nano open sets in nano topological spaces. Secondly, some properties for near nano open (closed sets. Also, we introduce the notion of nano β-continuity and we study the relationships between some types of nano continuous functions between nano topological spaces. Finally, we introduce two application examples in nano topology.

  1. Exploring Open-Ended Design Space of Mechatronic Systems

    Directory of Open Access Journals (Sweden)

    Zhun Fan

    2004-12-01

    Full Text Available To realize design automation of mechatronic systems, there are two major issues to be dealt with: open-topology generation of mechatronic systems and simulation or analysis of those models. For the first issue, we exploit the strong topology exploration capability of genetic programming to create and evolve structures representing mechatronic systems. With the use of ERCs (ephemeral random constants in genetic programming, we can evolve the sizing of mechatronic system components together with the system structures simultaneously. The second issue, simulation and analysis of those system models, is made more complex when the systems are mixed-energy-domain systems. We take advantage of bond graphs as a tool for multi- or mixed-domain modeling and simulation of mechatronic systems. Because there are many considerations in mechatronic system design that are not completely captured by a bond graph, it is beneficial to generate multiple solutions, allowing the designer more latitude in choosing a model to implement. The approach in this paper is capable of providing a variety of design choices to the designer for further analysis, comparison and trade-off study. The approach is shown to be efficient and effective and is demonstrated in an example of open-ended real-world mechatronic system design application, a typewriter re-design problem.

  2. DEVELOPMENT AND IMPLEMENTATION OF SMART-CMD IN THE OPEN EDUCATIONAL SPACE

    Directory of Open Access Journals (Sweden)

    Konstantin P. Dinnik

    2013-01-01

    Full Text Available In the work we highlight need to transform the educational-methodical complex in Smart-EMC in the open education space. For example, the modular structure of the discipline of the Insurance is demonstrated the composition and features of the Smart-EMC. The author depicts methodical techniques for teaching in open education system. 

  3. Metacognitive control and the spacing effect.

    Science.gov (United States)

    Son, Lisa K

    2010-01-01

    This study investigates whether the use of a spacing strategy absolutely improves final performance, even when the learner had chosen, metacognitively, to mass. After making judgments of learning, adult and child participants chose to mass or space their study of word pairs. However, 1/3 of their choices were dishonored. That is, they were forced to mass after having chosen to space and forced to space after having chosen to mass. Results showed that the spacing effect obtained for both adults and children when choices were honored. However, using a spacing strategy when it was in disagreement with the participant's own choice, or forced, did not enhance performance for the adults (Experiment 1). And although performance was enhanced for the children (beyond massing strategies), it was not as good as when the spacing decisions were self-chosen (Experiment 2). The data suggest that although spacing is an effective strategy for learning, it is not universal, particularly when the strategy is not chosen by the learner. In short, metacognitive control is often crucial and should be honored. (PsycINFO Database Record (c) 2009 APA, all rights reserved).

  4. Micropropulsion Systems for Precision Controlled Space Flight

    DEFF Research Database (Denmark)

    Larsen, Jack

    . This project is thus concentrating on developing a method by which an entire, ecient, control system compensating for the disturbances from the space environment and thereby enabling precision formation flight can be realized. The space environment is initially studied and the knowledge gained is used...... to deduce the requirements for a propulsion system consituting the actuator part of a control system eliminating the disturbances from the space environment. Due to the minute magnitudes of the forces to be delivered, this type of propulsion has been denoted Micropropulsion. Initially a theoretical study...... of the disturbance forces and their influence on a precision controlled spacecraft, is used to deduce the requirements for a micropropulsion system compensating for these. Following this an LTCC based resistojet microthruster is developed and fabricated, utilizing water as fuel. Towards the end of the project...

  5. Exploring Open-Ended Design Space of Mechatronic Systems

    DEFF Research Database (Denmark)

    Fan, Zhun; Wang, J.; Goodman, E.

    2004-01-01

    To realize design automation of mechatronic systems, there are two major issues to be dealt with: open-topology generation of mechatronic systems and simulation or analysis of those models. For the first issue, we exploit the strong topology exploration capability of genetic programming to create...... and evolve structures representing mechatronic systems. With the help of ERCs (ephemeral random constants) in genetic programming, we can also evolve the sizing of mechatronic system components along with the structures. The second issue, simulation and analysis of those system models, is made more complex...... when they represent mixed-energy-domain systems. We take advantage of bond graphs as a tool for multi- or mixed-domain modeling and simulation of mechatronic systems. Because there are many considerations in mechatronic system design that are not completely captured by a bond graph, we would like...

  6. Alternative utilization of underground spaces with abandoned mine openings

    Energy Technology Data Exchange (ETDEWEB)

    Chung, So Keul; Cho, Won Jai; Han, Kong Chang; Choi, Sung Oong [Korea Institute of Geology Mining and Materials, Taejon (Korea)

    1998-12-01

    Utilization of the openings of the abandoned mines could be planned by the principal parameters such as location and geotechnical impact. The local governments have not only to lead the each stage of the utilization project from the very beginning of conceptual design up to the construction stage, but also to promote the project for the development of public purpose. The possible tentative candidates for the utilization of the abandoned mine openings which are supported by the local governments could be summarized as follows. a. The Gahak mine of Kwangmyung, Kyunggi: The mine caverns which have been served as the storage of the pickled fishes, could be reexcavated by taking into consideration the geotechnical parameters for the public use such as: 1) Training center for the youth, 2) Fermentation and storehouse of marine products, 3) Sightseeing resort, 4) Sports and leisure complex, 5) Underground parking lot, 6) Underground shopping mall and chilled room storage, 7) Library, concert hall and museum. b. Hamtae mine of Taebaek, Kangwon: The Hambaek main haulage way and its shaft should be investigated in detail in order to find out a possible use as the underground challenging park of the coal mining operation. c. Mines of Boryung and Hongsung, Chungnam: Lots of mine caverns have been used as the storehouse for the pickled shrimp. However, they have to be promoted to a large scale industries. d. Imgok mine of Kwangju and Palbong mine of Jeongeup, Chunbuk: Mine caverns which have been used as the storehouse of pickles, need a detailed investigation for alternative promotion. e. Yongho mine of Pusan Dalsung mine of Taegu: Both of the mines are located near metropolitan communities. Reconstruction of the old mine caverns of the Yongho mine is highly recommended for a public use. The caverns of the Dalsung mine could be utilized as the storage facilities. Detailed geotechnical survey and sit investigation could be suggested to design the recommended facilities for both

  7. Opening Spaces of Academic Culture: Doors of Perception; Heaven and Hell

    Science.gov (United States)

    Habel, Chad; Whitman, Kirsty

    2016-01-01

    Academic culture is a distinct and unique field, and perhaps may best be conceptualised as a space. Although access to university has traditionally been restricted, recent efforts on a number of fronts have attempted to "open" the space of the academy. In particular, enabling programmes such as Preparatory Programs and Foundation Courses…

  8. 76 FR 51461 - Commercial Space Transportation Advisory Committee-Open Meeting

    Science.gov (United States)

    2011-08-18

    ... TRANSPORTATION Federal Aviation Administration Commercial Space Transportation Advisory Committee--Open Meeting AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Commercial Space Transportation... Act (Pub. L. 92-463, 5 U.S.C. App. 2), notice is hereby given of a meeting of the Commercial...

  9. 75 FR 16901 - Commercial Space Transportation Advisory Committee-Open Meeting

    Science.gov (United States)

    2010-04-02

    ... Federal Aviation Administration Commercial Space Transportation Advisory Committee--Open Meeting AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of Commercial Space Transportation Advisory.... 92-463, 5 U.S.C. App. 2), notice is hereby given of the meetings of the Commercial...

  10. Going Open: Does it Mean Giving Away Control?

    Directory of Open Access Journals (Sweden)

    Michael Weiss

    2013-01-01

    Full Text Available Open source software has evolved from being an effort driven by a collective of volunteers to become an integral part of commercial software. Constant demands for new features besides maintaining product quality made companies seek open source as an answer for these demands. These growing demands brought with them control of quality, architecture, contribution management, and community management. This article explores the governance strategies adopted by open source software projects to manage the quality of complements (such as plug-ins that extend a platform's functionality developed by community members outside the core team. The outcomes of the research contribute to our understanding of the strategies followed by different open source platform owners (the open source project initiators to manage external innovation in the case of platform extensions in two areas: i governance models and ii regulatory tools.

  11. Optimizing Ocean Space: Co-siting Open Ocean Aquaculture

    Science.gov (United States)

    Cobb, B. L.; Wickliffe, L. C.; Morris, J. A., Jr.

    2016-12-01

    In January of 2016, NOAA's National Marine Fisheries Service released the Gulf Aquaculture Plan (GAP) to manage the development of environmentally sound and economically sustainable open ocean finfish aquaculture in the Gulf of Mexico (inside the U.S. Exclusive Economic Zone [EEZ]). The GAP provides the first regulatory framework for aquaculture in federal waters with estimated production of 64 million pounds of finfish, and an estimated economic impact of $264 million annually. The Gulf of Mexico is one of the most industrialized ocean basins in the world, with many existing ocean uses including oil and natural gas production, shipping and commerce, commercial fishing operations, and many protected areas to ensure conservation of valuable ecosystem resources and services. NOAA utilized spatial planning procedures and tools identifying suitable sites for establishing aquaculture through exclusion analyses using authoritative federal and state data housed in a centralized geodatabase. Through a highly collaborative, multi-agency effort a mock permitting exercise was conducted to illustrate the regulatory decision-making process for the Gulf. Further decision-making occurred through exploring co-siting opportunities with oil and natural gas platforms. Logistical co-siting was conducted to reduce overall operational costs by looking at distance to major port and commodity tonnage at each port. Importantly, the process of co-siting allows aquaculture to be coupled with other benefits, including the availability of previously established infrastructure and the reduction of environmental impacts.

  12. An open cycle gas core fusion rocket for space exploration

    Science.gov (United States)

    Kammash, T.; Godfrey, T.

    A nuclear propulsion system that utilizes fusion reactions to heat a plasma in a magnetically confined device is examined as a potential rocket. It makes use of a high density plasma in a magnetic mirror geometry with a collision mean free path much shorter than its length. Under these conditions the plasma behaves like a fluid with confinement properties dictated by gasdynamic laws. Accordingly, the plasma escape from the device is analogous to the flow of a gas into vacuum from a vessel with a hole. Such a system is capable of producing a very high specific impulse albeit at modest thrust. One approach for enhancing the thrust is to use an auxiliary hydrogen propellant that could be regeneratively heated before it is introduced into the reactor chamber. As is flows past the fusion plasma it will be further heated by the radiation (bremsstrahlung and synchrotron) emanating from the plasma, and upon emergence from the nozzle it will generate the desired thrust. The system thus functions much like an open cycle gas core rocket with very attractive propulsive capabilities. In this paper we present the underlying physics principles of such a concept and assess its capability by applying the results to a round trip mission to Mars. It is shown that the propulsion parameters exceed those of a gas core fission reactor and without many of major hydrodynamic problems confronted by the latter.

  13. Exploring Open-Ended Design Space of Mechatronic Systems

    Directory of Open Access Journals (Sweden)

    Zhun Fan

    2008-11-01

    Full Text Available To realize design automation of mechatronic systems, there are two major issues to be dealt with: opentopology generation of mechatronic systems and simulation or analysis of those models. For the first issue, we exploit the strong topology exploration capability of genetic programming to create and evolve structures representing mechatronic systems. With the use of ERCs (ephemeral random constants in genetic programming, we can evolve the sizing of mechatronic system components together with the system structures simultaneously. The second issue, simulation and analysis of those system models, is made more complex when the systems are mixed-energy-domain systems. We take advantage of bond graphs as a tool for multi- or mixed-domain modeling and simulation of mechatronic systems. Because there are many considerations in mechatronic system design that are not completely captured by a bond graph, it is beneficial to generate multiple solutions, allowing the designer more latitude in choosing a model to implement. The approach in this paper is capable of providing a variety of design choices to the designer for further analysis, comparison and trade-off study. The approach is shown to be efficient and effective and is demonstrated in an example of open-ended real-world mechatronic system design application, a typewriter re-design problem.

  14. Open Cultural Spaces in Search of New Frontiers

    Directory of Open Access Journals (Sweden)

    Nada Švob-Đokić

    2008-09-01

    Full Text Available Crossing cultural borders opens up a new creativity, new expectations and new emptiness that provoke fear and existential nausea. Are we lost forever, in a specific historical time, in a specific culture, or in a specific geographical location? Are we forgotten in transitions, translations and intercultural misunderstandings? Are we bound to remain foreigners forever? In order to provide some answers, we hurriedly establish new borders and define new relations between the recently-established entities, a new creativity or a new understanding and knowledge that can help us to survive the confrontation with a limitless nihility. In the age of globalisation, an increased effort to position cultural creativity and cultural identification within the local, now multicultural and largely redefined context, is strongly felt. How does this affect people and societies? What are the limits of transgressions between cultures and different cultural values? How can the new cultural identities be redefined? The answers to these questions can turn out to be very different, but they seem to be confined to at least two already discernible directions: cultural hybridisation (García Canclini and the emergence of virtual cultures that promote de-standardised identities.

  15. Valuing urban open space using the travel-cost method and the implications of measurement error.

    Science.gov (United States)

    Hanauer, Merlin M; Reid, John

    2017-08-01

    Urbanization has placed pressure on open space within and adjacent to cities. In recent decades, a greater awareness has developed to the fact that individuals derive multiple benefits from urban open space. Given the location, there is often a high opportunity cost to preserving urban open space, thus it is important for both public and private stakeholders to justify such investments. The goals of this study are twofold. First, we use detailed surveys and precise, accessible, mapping methods to demonstrate how travel-cost methods can be applied to the valuation of urban open space. Second, we assess the degree to which typical methods of estimating travel times, and thus travel costs, introduce bias to the estimates of welfare. The site we study is Taylor Mountain Regional Park, a 1100-acre space located immediately adjacent to Santa Rosa, California, which is the largest city (∼170,000 population) in Sonoma County and lies 50 miles north of San Francisco. We estimate that the average per trip access value (consumer surplus) is $13.70. We also demonstrate that typical methods of measuring travel costs significantly understate these welfare measures. Our study provides policy-relevant results and highlights the sensitivity of urban open space travel-cost studies to bias stemming from travel-cost measurement error. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Learning to Control Opening and Closing a Myoelectric Hand

    OpenAIRE

    2010-01-01

    Bouwsema H, van der Sluis CK, Bongers RM. Learning to control opening and closing a myoelectric hand. Arch Phys Med Rehabil 2010;91:1442-6. Objective: To compare 3 different types of myoelectric signal training. Design: A cohort analytic study. Setting: University laboratory. Participants: Able-bodied right-handed participants (N=34) randomly assigned to 1 of 3 groups. Interventions: Participants trained hand opening and closing on 3 consecutive days. One group trained with a virtual myoelect...

  17. Open versus Controlled-Access Data | Office of Cancer Genomics

    Science.gov (United States)

    OCG employs stringent human subjects’ protection and data access policies to protect the privacy and confidentiality of the research participants. Depending on the risk of patient identification, OCG programs data are available to the scientific community in two tiers: open or controlled access. Both types of data can be accessed through its corresponding OCG program-specific data matrix or portal. Open-access Data

  18. Economics of Peppers and Salad Cucumbers Production on an Open Land and in a Protected Space

    Directory of Open Access Journals (Sweden)

    Silvio Pozderec

    2014-02-01

    Full Text Available The research is based on the economic analysis of growing peppers (Capsicum annum L. and salad cucumbers (Cucumis sativus L. in an open land and in a protected space. For this purpose the simulation models were developed for the growing of the peppers and salad cucumbers that were based on the technological-economic input data for two growing systems, in the open and in the protected space. The results of the economic analysis show that the growing of peppers and salad cucumbers in the protected space is more profi table than growing them in the open land. The growing of salad cucumbers in the protected space has proven to be more reasonable than growing peppers, as the coefficient of economics (Ce of growing salad cucumbers reached the value Ce = 1.4, while the value in growing peppers was Ce = 1.1. This was also confirmed with two scenarios that were analysed using the sensitivity analysis.

  19. Economics of Peppers and Salad Cucumbers Production on an Open Land and in a Protected Space

    Directory of Open Access Journals (Sweden)

    Silvio Pozderec

    2010-09-01

    Full Text Available The research is based on the economic analysis of growing peppers (Capsicum annum L. and salad cucumbers (Cucumis sativus L. in an open land and in a protected space. For this purpose the simulation models were developed for the growing of the peppers and salad cucumbers that were based on the technological-economic input data for two growing systems, in the open and in the protected space. The results of the economic analysis show that the growing of peppers and salad cucumbers in the protected space is more profi table than growing them in the open land. The growing of salad cucumbers in the protected space has proven to be more reasonable than growing peppers, as the coefficient of economics (Ce of growing salad cucumbers reached the value Ce = 1.4, while the value in growing peppers was Ce = 1.1. This was also confirmed with two scenarios that were analysed using the sensitivity analysis.

  20. The impacts of open-mouth breathing on upper airway space in obstructive sleep apnea: 3-D MDCT analysis.

    Science.gov (United States)

    Kim, Eun Joong; Choi, Ji Ho; Kim, Kang Woo; Kim, Tae Hoon; Lee, Sang Hag; Lee, Heung Man; Shin, Chol; Lee, Ki Yeol; Lee, Seung Hoon

    2011-04-01

    Open-mouth breathing during sleep is a risk factor for obstructive sleep apnea (OSA) and is associated with increased disease severity and upper airway collapsibility. The aim of this study was to investigate the effect of open-mouth breathing on the upper airway space in patients with OSA using three-dimensional multi-detector computed tomography (3-D MDCT). The study design included a case-control study with planned data collection. The study was performed at a tertiary medical center. 3-D MDCT analysis was conducted on 52 patients with OSA under two experimental conditions: mouth closed and mouth open. Under these conditions, we measured the minimal cross-sectional area of the retropalatal and retroglossal regions (mXSA-RP, mXSA-RG), as well as the upper airway length (UAL), defined as the vertical dimension from hard palate to hyoid. We also computed the volume of the upper airway space by 3-D reconstruction of both conditions. When the mouth was open, mXSA-RP and mXSA-RG significantly decreased and the UAL significantly increased, irrespective of the severity of OSA. However, between the closed- and open-mouth states, there was no significant change in upper airway volume at any severity of OSA. Results suggest that the more elongated and narrow upper airway during open-mouth breathing may aggravate the collapsibility of the upper airway and, thus, negatively affect OSA severity.

  1. The Impact of Green Open Space on Community Attachment—A Case Study of Three Communities in Beijing

    Directory of Open Access Journals (Sweden)

    Yuemei Zhu

    2017-04-01

    Full Text Available With the development of urbanization in China, the quality of urban life and community attachment have attracted increasing attention of the governments and society. Existing research on community attachment has mainly examined how individual characteristics affect community attachment, such as their length of residence and socioeconomic status. However, some scholars have become interested in exploring the effects of green open space on community attachment. This research examined whether the distribution of green open space in communities had significant effects on community attachment, and both the impact and path were also investigated. Through a questionnaire survey, relevant data in three communities of Beijing were collected. The impact of green open space layout on community attachment was evaluated by using hierarchical regression, and the impact path was examined by using a structural equation model. The results showed that green open space in a community had significant effects on the community attachment, with centralized green open space layout having a greater effect than that of dispersed green open space. Moreover, the more complex the shape of green open space is, the greater the impact is. The degree of satisfaction with the green open space had direct effects on the community attachment. The accessibility and perceived area of green open space could indirectly have an impact on the community attachment by affecting the degree of satisfaction with the green open space. Nevertheless, residents’ perceived importance of green open space could affect the community attachment directly and indirectly, as it affects the degree of satisfaction.

  2. An Open-Control Concept for a Holonic Multiagent System

    Science.gov (United States)

    Adam, Emmanuel; Berger, Thierry; Sallez, Yves; Trentesaux, Damien

    MAS are particularly adapted to deal with distributed and dynamic environment. The management of business workflow, or data flow, flexible manufacturing systems is typically a good application field for them. This kind of application requires centralization of the data control and flexibility to face with changes on the network. In the context of FMS, where products and resources entities can be seen as active, this paper presents the open-control concept and gives an example of its instantiation with holonic scheme. The open-control concept proposed in this paper exhibits the classic explicit control, as well as an innovative type of control called implicit control that allows system entities to be influenced via an Optimization Mechanism (OM). We illustrate our proposition by an implementation on a flexible assembly cell in our university.

  3. Controlling open quantum systems: tools, achievements, and limitations

    Science.gov (United States)

    Koch, Christiane P.

    2016-06-01

    The advent of quantum devices, which exploit the two essential elements of quantum physics, coherence and entanglement, has sparked renewed interest in the control of open quantum systems. Successful implementations face the challenge of preserving relevant nonclassical features at the level of device operation. A major obstacle is decoherence, which is caused by interaction with the environment. Optimal control theory is a tool that can be used to identify control strategies in the presence of decoherence. Here we review recent advances in optimal control methodology that allow typical tasks in device operation for open quantum systems to be tackled and discuss examples of relaxation-optimized dynamics. Optimal control theory is also a useful tool to exploit the environment for control. We discuss examples and point out possible future extensions.

  4. The geography of recreational open space: influence of neighborhood racial composition and neighborhood poverty.

    Science.gov (United States)

    Duncan, Dustin T; Kawachi, Ichiro; White, Kellee; Williams, David R

    2013-08-01

    The geography of recreational open space might be inequitable in terms of minority neighborhood racial/ethnic composition and neighborhood poverty, perhaps due in part to residential segregation. This study evaluated the association between minority neighborhood racial/ethnic composition, neighborhood poverty, and recreational open space in Boston, Massachusetts (US). Across Boston census tracts, we computed percent non-Hispanic Black, percent Hispanic, and percent families in poverty as well as recreational open space density. We evaluated spatial autocorrelation in study variables and in the ordinary least squares (OLS) regression residuals via the Global Moran's I. We then computed Spearman correlations between the census tract socio-demographic characteristics and recreational open space density, including correlations adjusted for spatial autocorrelation. After this, we computed OLS regressions or spatial regressions as appropriate. Significant positive spatial autocorrelation was found for neighborhood socio-demographic characteristics (all p value = 0.001). We found marginally significant positive spatial autocorrelation in recreational open space (Global Moran's I = 0.082; p value = 0.053). However, we found no spatial autocorrelation in the OLS regression residuals, which indicated that spatial models were not appropriate. There was a negative correlation between census tract percent non-Hispanic Black and recreational open space density (r S = -0.22; conventional p value = 0.005; spatially adjusted p value = 0.019) as well as a negative correlation between predominantly non-Hispanic Black census tracts (>60 % non-Hispanic Black in a census tract) and recreational open space density (r S = -0.23; conventional p value = 0.003; spatially adjusted p value = 0.007). In bivariate and multivariate OLS models, percent non-Hispanic Black in a census tract and predominantly Black census tracts were associated with

  5. Control of nonlinear flexible space structures

    Science.gov (United States)

    Shi, Jianjun

    With the advances made in computer technology and efficiency of numerical algorithms over last decade, the MPC strategies have become quite popular among control community. However, application of MPC or GPC to flexible space structure control has not been explored adequately in the literature. The work presented in this thesis primarily focuses on application of GPC to control of nonlinear flexible space structures. This thesis is particularly devoted to the development of various approximate dynamic models, design and assessment of candidate controllers, and extensive numerical simulations for a realistic multibody flexible spacecraft, namely, Jupiter Icy Moons Orbiter (JIMO)---a Prometheus class of spacecraft proposed by NASA for deep space exploratory missions. A stable GPC algorithm is developed for Multi-Input-Multi-Output (MIMO) systems. An end-point weighting (penalty) is used in the GPC cost function to guarantee the nominal stability of the closed-loop system. A method is given to compute the desired end-point state from the desired output trajectory. The methodologies based on Fake Algebraic Riccati Equation (FARE) and constrained nonlinear optimization, are developed for synthesis of state weighting matrix. This makes this formulation more practical. A stable reconfigurable GPC architecture is presented and its effectiveness is demonstrated on both aircraft as well as spacecraft model. A representative in-orbit maneuver is used for assessing the performance of various control strategies using various design models. Different approximate dynamic models used for analysis include linear single body flexible structure, nonlinear single body flexible structure, and nonlinear multibody flexible structure. The control laws evaluated include traditional GPC, feedback linearization-based GPC (FLGPC), reconfigurable GPC, and nonlinear dissipative control. These various control schemes are evaluated for robust stability and robust performance in the presence of

  6. On Modeling and Constrained Model Predictive Control of Open Irrigation Canals

    Directory of Open Access Journals (Sweden)

    Lihui Cen

    2017-01-01

    Full Text Available This paper proposes a model predictive control of open irrigation canals with constraints. The Saint-Venant equations are widely used in hydraulics to model an open canal. As a set of hyperbolic partial differential equations, they are not solved explicitly and difficult to design optimal control algorithms. In this work, a prediction model of an open canal is developed by discretizing the Saint-Venant equations in both space and time. Based on the prediction model, a constrained model predictive control was firstly investigated for the case of one single-pool canal and then generalized to the case of a cascaded canal with multipools. The hydraulic software SICC was used to simulate the canal and test the algorithms with application to a real-world irrigation canal of Yehe irrigation area located in Hebei province.

  7. Development of a robot Holon using an open modular controller

    DEFF Research Database (Denmark)

    Schnell, Jakob; Andersen, Søren; Sørensen, Christian

    1999-01-01

    System (HoMuCS) architecture and methodology for implementing a HMS. This paper specifically reviews the development of a Robot Holon based on an open controller in the context of the HoMuCS architecture. The paper will describe the results and research work that was involved in developing a robot holon...... for a physical robot. The robot holon was implemented on an existing robot at the department which was upgraded by removing its native control system and replacing it with a new PC-based open controller. The development of the robot holon builds on the notion that a robot holon will be able to performboth......Holonic Manufacturing Systems (HMS) has during the last period presented itself as an advantageous theoretical foundation for the problems that arise in controlling agile manufacturing systems. Previous research, at the Department, has demonstrated how modern shop floor control systems can...

  8. Nearest level spacing statistics in open chaotic systems: generalization of the Wigner surmise.

    Science.gov (United States)

    Poli, Charles; Luna-Acosta, Germán A; Stöckmann, Hans-Jürgen

    2012-04-27

    We investigate the nearest level spacing statistics of open chaotic wave systems. To this end we derive the spacing distributions for the three Wigner ensembles in the one-channel case. The theoretical results give a clear physical meaning of the modifications on the spacing distributions produced by the coupling to the environment. Based on the analytical expressions obtained, we then propose general expressions of the spacing distributions for any number of channels, valid from weak to strong coupling. The latter expressions contain one free parameter. The surmise is successfully compared with numerical simulations of non-Hermitian random matrices and with experimental data obtained with a lossy electromagnetic chaotic cavity.

  9. Impact of suntracking on Space Station controllability

    Science.gov (United States)

    Chipman, Richard; Hu, Tsay-Hsin G.; Barber, Mark; Holmes, Eric

    The multibody dynamics of the Space Station is studied as affected by the suntracking motions of the photovotaic arrays. Dynamic responses are simulated for the Station being controlled by control moment gyros (CMGs). Controllability is shown to be a function of flight orientation, stage (inertial properties, CP-CG offset) and the suntracking dynamics. For certain combinations of these parameters, the aerodynamic, inertial disturbances and motor torques from alpha joint(s) arising from near-perfect suntracking are too large for the control moment gyro system to control. However, by imposing slight restrictions on the dynamics of the suntracking, CMGs are able to provide Station attitude stability with excellent pointing performance and an excellent microgravity environment.

  10. Space-Mass Relation And Gravity In A Geometrically Open Space Universe

    Directory of Open Access Journals (Sweden)

    Saravanan Govindaraj

    2015-04-01

    Full Text Available Abstract Gravity is a property of space-time fabric and not a universal force of attraction between two objects with mass. Considering that energy is distributed in space-time while mass replaces space-time from its place producing a denser or warped space-time around the mass problems regarding the nature of gravity can be addressed. This paper talks about understanding the nature of gravity as a virtual force created by warped space time and also explains what gives a particle its mass. Irrespective of mass gravity can exist anywhere in the universe but can be experienced only by the presence of mass or by distributing of energy through it. Mass is a void in space-time but in real world matter exists in their smallest form as sub-atomic particles separated with a space-time. If a particle is said to have a greater energy then it has created a relatively bigger void in space-time.

  11. Investigating the Impact of Schools' Open Space on Learning and Educational Achievement of Elementary Students

    Directory of Open Access Journals (Sweden)

    Abdolreza Gilavand

    2016-04-01

    Full Text Available Background It is obvious that most of informal learnings of social skills and constructive plays occur in school yards and play-fields where children spend much of their non-official time of teaching. This study aimed to investigate the impact of schools' open space on learning and educational achievement of elementary students in Ahvaz, Southwest of Iran. Materials and Methods At a cross-sectional study, 210 students were selected randomly as sample of study. Data collection tools included Hermance’s achievement motivation questionnaire and researcher-constructed questionnaire (observation checklist to examine the physical parameters of learning schools' open space and interviews with students. Data of study were analyzed in SPSS- 21 software. Results Results of this study showed that schools' open space has a significant impact on learning and academic achievement of elementary school students in Ahvaz- Iran (P

  12. Common front end systems for Space Shuttle and Space Station control centers at Johnson Space Center

    Science.gov (United States)

    Uljon, Linda; Muratore, John

    1993-03-01

    In the beginning of the fiscal year 1992, the development organizations of Johnson Space Center (JSC) were poised to begin two major projects: the Space Station Control Center and the refurbishment of the telemetry processing area of the Space Shuttle Mission Control Center. A study team established that a common front end concept could be used and could reduce development costs for both projects. A standard processor was defined to support most of the front end functions of both control centers and supports a consolidation of control positions which effectively reduces operations cost. This paper defines that common concept and describes the progress that has been made in development of the Consolidated Communications Facility (CCF) during the past year.

  13. Learning to Control Opening and Closing a Myoelectric Hand

    NARCIS (Netherlands)

    Bouwsema, Hanneke; van der Sluis, Corry K.; Bongers, Raoul M.

    2010-01-01

    Bouwsema H, van der Sluis CK, Bongers RM. Learning to control opening and closing a myoelectric hand. Arch Phys Med Rehabil 2010;91:1442-6. Objective: To compare 3 different types of myoelectric signal training. Design: A cohort analytic study. Setting: University laboratory. Participants: Able-bodi

  14. Space Station Control Moment Gyroscope Lessons Learned

    Science.gov (United States)

    Gurrisi, Charles; Seidel, Raymond; Dickerson, Scott; Didziulis, Stephen; Frantz, Peter; Ferguson, Kevin

    2010-01-01

    Four 4760 Nms (3510 ft-lbf-s) Double Gimbal Control Moment Gyroscopes (DGCMG) with unlimited gimbal freedom about each axis were adopted by the International Space Station (ISS) Program as the non-propulsive solution for continuous attitude control. These CMGs with a life expectancy of approximately 10 years contain a flywheel spinning at 691 rad/s (6600 rpm) and can produce an output torque of 258 Nm (190 ft-lbf)1. One CMG unexpectedly failed after approximately 1.3 years and one developed anomalous behavior after approximately six years. Both units were returned to earth for failure investigation. This paper describes the Space Station Double Gimbal Control Moment Gyroscope design, on-orbit telemetry signatures and a summary of the results of both failure investigations. The lessons learned from these combined sources have lead to improvements in the design that will provide CMGs with greater reliability to assure the success of the Space Station. These lessons learned and design improvements are not only applicable to CMGs but can be applied to spacecraft mechanisms in general.

  15. Open quantum system approach to the Gibbons-Hawking effect of de Sitter space-time.

    Science.gov (United States)

    Yu, Hongwei

    2011-02-11

    We analyze, in the paradigm of open quantum systems, the reduced dynamics of a freely falling two-level detector in de Sitter space-time in weak interaction with a reservoir of fluctuating quantized conformal scalar fields in the de Sitter-invariant vacuum. We find that the detector is asymptotically driven to a thermal state at the Gibbons-Hawking temperature, regardless of its initial state. Our discussion, therefore, shows that the Gibbons-Hawking effect of de Sitter space-time can be understood as a manifestation of thermalization phenomena that involves decoherence and dissipation in open quantum systems.

  16. Dynamic control of the space tethered system

    Science.gov (United States)

    Malashin, A. A.; Smirnov, N. N.; Bryukvina, O. Yu.; Dyakov, P. A.

    2017-02-01

    We discuss the problem of simultaneous dynamical stabilization and suppression of transverse and longitudinal vibrations of the space tethered system deployed along a certain trajectory. The dynamics of the system is described by a system of nonlinear partial differential equations for the longitudinal and transverse waves and we consider a non-classical version of the problem with one moving boundary. We formulate a mathematical model and perform the analytic and numerical analysis of the boundary control problem based on the Lyapunov method. A scheme of the deployment mechanism is suggested. It includes a control torque and transverse displacement of the boundary and ensures stable deployment of the whole system.

  17. Federated Space-Time Query for Earth Science Data Using OpenSearch Conventions

    Science.gov (United States)

    Lynnes, Chris; Beaumont, Bruce; Duerr, Ruth; Hua, Hook

    2009-01-01

    This slide presentation reviews a Space-time query system that has been developed to assist the user in finding Earth science data that fulfills the researchers needs. It reviews the reasons why finding Earth science data can be so difficult, and explains the workings of the Space-Time Query with OpenSearch and how this system can assist researchers in finding the required data, It also reviews the developments with client server systems.

  18. Field-oriented control of five-phase induction motor with open-end stator winding

    Directory of Open Access Journals (Sweden)

    Listwan Jacek

    2016-09-01

    Full Text Available The mathematical model of the five-phase squirrel-cage induction motor and the system of the dual five-phase voltage source inverter have been presented. The control methods and control systems of the field-oriented control of the five-phase induction motor with an open-end stator winding are described. The structures of the direct fieldoriented control system (DFOC and the Indirect Field-oriented control system (IFOC with PI controllers in outer and inner control loops are analyzed. A method of space vector modulation used to control the system of the dual five-phase voltage source inverter has been discussed. The results of simulation studies of the field-oriented control methods are presented. Comparative analysis of the simulation results was carried out.

  19. Controls of eolian dune size and spacing

    Science.gov (United States)

    Lancaster, N.

    1988-11-01

    Data for the Namib and Gran Desierto sand seas suggest that the controls of dune size and spacing are complex. The relation between dune height and spacing varies with dune type and location and reflects both dune dynamics (vertical accretion vs. migration or extension) and availability of sand. There is no general relation between dune spacing and grain size. In the Namib sand sea the height of compound and complex dunes (draas) is inversely proportional to potential sand-transport rates, whereas the height of dunes superimposed on their flanks varies directly with potential sand-transport rates. These observations can be combined with data on dune spacing to demonstrate the existence of a hierarchy of eolian dunes, each element of which responds to variations in sand-transport rates at different temporal and spatial scales. Whereas the morphology of individual simple dunes and superimposed dunes on draas is related to contemporary rates and directions of sand transport, the morphology and development of draas reflects long-term and regional patterns of sand transport and deposition.

  20. The Conductive Thermal Control Material Systems for Space Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal is submitted to develop and demonstrate the feasibility of processing the space environment stable, multifunctional thermal control material system...

  1. Open Hypermedia as User Controlled Meta Data for the Web

    DEFF Research Database (Denmark)

    Grønbæk, Kaj; Sloth, Lennert; Bouvin, Niels Olof

    2000-01-01

    distributed open hypermedia linking between Web pages and WebDAV aware desktop applications. The paper describes the OHIF format and demonstrates how the Webvise system handles OHIF. Finally, it argues for better support for handling user controlled meta data, e.g. support for linking in non-XML data......This paper introduces an approach to utilise open hypermedia structures such as links, annotations, collections and guided tours as meta data for Web resources. The paper introduces an XML based data format, called Open Hypermedia Interchange Format - OHIF, for such hypermedia structures. OHIF...... segments. By means of the Webvise system, OHIF structures can be authored, imposed on Web pages, and finally linked on the Web as any ordinary Web resource. Following a link to an OHIF file automatically invokes a Webvise download of the meta data structures and the annotated Web content will be displayed...

  2. Open-space preservation in the Netherlands: Planning, practice and prospects

    NARCIS (Netherlands)

    Koomen, E.; Dekkers, J.; Dijk, van T.

    2008-01-01

    Open-space preservation is a planner's issue that is constantly debated, in particular on the success of the implemented instruments. Assessments of policy effectiveness face many methodological problems that are briefly discussed here. We choose to analyse the contribution of Dutch policies to

  3. Open-space preservation in the Netherlands : Planning, practice and prospects

    NARCIS (Netherlands)

    Koomen, Eric; Dekkers, Jasper; van Dijk, Terry

    Open-space preservation is a planner's issue that is constantly debated, in particular on the success of the implemented instruments. Assessments of policy effectiveness face many methodological problems that are briefly discussed here. We choose to analyse the contribution of Dutch policies to

  4. Butterflies Diversity in Brawijaya University, Veteran, Jakarta and Velodrom Green Open Space

    Directory of Open Access Journals (Sweden)

    Ayu Raisa Khairun Nisa'

    2013-05-01

    Full Text Available Butterflies have some roles in environmental as pollinator and bioindicator. Habitat is one of important factor to support butterflies growth. The aim of this research was to describe butterflies diversity in some green open spaces in Malang. Direct observations of butterflies diversity, vegetation structures and abiotic factors in Brawijaya University, Veteran, Jakarta and Velodrom Green Open Space were conducted on June 2012. Sampling was took place in each sites using cruising method in three times observation at 07.00, 11.00 a.m. and 3.30 p.m . Data were analyzed by statistical descriptive using Microsoft Excel 2007 and PAST. The result showed that butterflies composition in all sites dominated by Delias sp., Leptosia nina and Eurema venusta. The diversity index of all sites showed moderate rank that indicate communities equilibrium in environment was still good. In this case, Velodrom Green Open Space has the highest one of diversity index, it was about 2,199. Brawijaya University and Jakarta Green Open Space have a high similarity index based on Morisita Index. The highest abundance of butterflies was observed at 11.00-12.30 a.m. Delias sp. and Leptosia nina has temporal spread all day long, while Eurema venusta just in day light.

  5. Open space in human settlements: the lesson from the Islamic tradition.

    NARCIS (Netherlands)

    Germeraad, P.W.

    1990-01-01

    The pressure on the development of adequate open space systems in the Arab-Muslim countries in the Middle East is growing due to: massive migration to the cities, changes in the patterns of life and social networks, and an increasing growth in population. This process results in the development of n

  6. COSMO: a decision-support system for the central open space, the Netherlands

    NARCIS (Netherlands)

    Harms, W.B.; Knaapen, J.P.; Roos-Klein-Lankhorst sic, J.

    1995-01-01

    To evaluate scenarios for nature restoration, a landscape ecological decision-support system has been developed, a knowledge-based system integrated in a geographical information system. The grid-based application in the Central Open Space of the Netherlands (the COSMO model) is presented here. Four

  7. The role of open space in urban neighbourhoods for health-related lifestyle.

    Science.gov (United States)

    Lestan, Katarina Ana; Eržen, Ivan; Golobič, Mojca

    2014-06-01

    The research reported in this paper addresses the relationship between quality of open space and health related lifestyle in urban residential areas. The research was performed in the residential developments in Ljubljana, Slovenia, dating from the time of political and economic changes in the early nineties. Compared to the older neighborhoods, these are typically single-use residential areas, with small open spaces and poor landscape design. The research is concerned with the quality of life in these areas, especially from the perspective of the vulnerable users, like the elderly and children. Both depend on easily accessible green areas in close proximity to their homes. The hypothesis is that the poor open space quality affects their health-related behavior and their perceived health status. The research has three methodological phases: (1) a comparison between urban residential areas by criteria describing their physical characteristics; (2) behavior observation and mapping and (3) a resident opinion survey. The results confirm differences between open spaces of the selected residential areas as well as their relation with outdoor activities: a lack of outdoor programs correlates with poor variety of outdoor activities, limited to transition type, less time spent outdoors and lower satisfaction with their home environment. The survey also disclosed a strong influence of a set of socio-economic variables such as education and economic status on physical activity and self-perceived health status of people. The results therefore confirm the hypothesis especially for less affluent and educated; i.e., vulnerable groups.

  8. COSMO: a decision-support system for the central open space, the Netherlands

    NARCIS (Netherlands)

    Harms, W.B.; Knaapen, J.P.; Roos-Klein-Lankhorst sic, J.

    1995-01-01

    To evaluate scenarios for nature restoration, a landscape ecological decision-support system has been developed, a knowledge-based system integrated in a geographical information system. The grid-based application in the Central Open Space of the Netherlands (the COSMO model) is presented here. Four

  9. 77 FR 13261 - Request for Applications: The Community Forest and Open Space Conservation Program

    Science.gov (United States)

    2012-03-06

    ... Forest Service Request for Applications: The Community Forest and Open Space Conservation Program AGENCY..., State and Private Forestry, Cooperative Forestry staff, published a document in the Federal Register of... Conservation Program (Community Forest Program or CFP). The document contained incorrect funding information...

  10. Best Management Practice, Fact Sheet 2. Sheet Flow to Open Space

    OpenAIRE

    2013-01-01

    This publication explains what sheet flow to open space is, where and how it is used, their limitations, routine and nonroutine maintenance, expected costs, and a glossary of terms. This fact sheet is one of a 15-part series on urban stormwater management practices.

  11. The Role of Open Space in Urban Neighbourhoods for Health-Related Lifestyle

    Directory of Open Access Journals (Sweden)

    Katarina Ana Lestan

    2014-06-01

    Full Text Available The research reported in this paper addresses the relationship between quality of open space and health related lifestyle in urban residential areas. The research was performed in the residential developments in Ljubljana, Slovenia, dating from the time of political and economic changes in the early nineties. Compared to the older neighborhoods, these are typically single-use residential areas, with small open spaces and poor landscape design. The research is concerned with the quality of life in these areas, especially from the perspective of the vulnerable users, like the elderly and children. Both depend on easily accessible green areas in close proximity to their homes. The hypothesis is that the poor open space quality affects their health-related behavior and their perceived health status. The research has three methodological phases: (1 a comparison between urban residential areas by criteria describing their physical characteristics; (2 behavior observation and mapping and (3 a resident opinion survey. The results confirm differences between open spaces of the selected residential areas as well as their relation with outdoor activities: a lack of outdoor programs correlates with poor variety of outdoor activities, limited to transition type, less time spent outdoors and lower satisfaction with their home environment. The survey also disclosed a strong influence of a set of socio-economic variables such as education and economic status on physical activity and self-perceived health status of people. The results therefore confirm the hypothesis especially for less affluent and educated; i.e., vulnerable groups.

  12. CERN opens up its control rooms to youngsters

    CERN Multimedia

    CERN Bulletin

    2011-01-01

    CERN is inviting 13 to 18 year-olds to come and spend a couple of hours in the control rooms of the LHC and its experiments. Registration is now open.   Is your neighbour's kid eager to come and see what's going on in the CERN control rooms for himself? Is your niece from Germany fascinated by the famous accelerator near Geneva that she's heard about and asking to know more? Then Researchers Night is for them! From 6.00 p.m. on Friday 23 September until 1.00 a.m. the following morning, the LHC and its experiments will open their doors to 13 to 18 year-olds. They are invited to come and spend a couple of hours in the control rooms watching the physicists and taking part in various activities. ALICE, ATLAS, CMS, LHCb, TOTEM, and the CERN Control Centre (CCC) will all be welcoming visitors. For this second year of CERN's involvement in European Researchers Night, the CERN exhibitions will be open late and special activities will be organised in Microcosm....

  13. Public opinion and interest group positions on open-space issues in Albuquerque, New Mexico, USA: Implications for resource management

    Science.gov (United States)

    Tannery, Thomas Allan

    1987-07-01

    The purpose of this research was to elicit and compare the open-space preferences of citizens and openspace experts in Albuquerque, New Mexico, USA. A randomly selected sample of 492 citizens and 35 open-space experts participated in a telephone survey during May 5 18, 1986. The following hypothesis was tested and used as a guideline for the study: HO1: There is no significant difference between respondents' status and preference for open space in Albuquerque, New Mexico. The hypothesis was rejected. Findings confirmed respondents' status affected preference for open space. Of the eight issues on which the citizen and expert groups were compared, five recorded significant differences in response profiles. The open-space expert group was significantly more supportive of using open space to accommodate offroad vehicle facilities, wildlife preserves, a citywide recreational trail, and a trail system along the arroyos and city ditches. The citizen sample was significantly more supportive of using open space to accommodate overnight camping facilities. Both groups equally supported using open space to accommodate an outdoor amphitheater, outdoor education facilities, and rafting, kayaking, and canoeing facilities. The finding indicated that expert preferences did not represent an aggregate of citizen preferences for managing open-space resources. Understanding both expert and citizen positions will facilitate decision-making processes and help resolve environmental disputes.

  14. Perception of open urban space – Bevk square in Nova Gorica

    Directory of Open Access Journals (Sweden)

    Nataša Bratina

    1997-01-01

    Full Text Available In research on perception of open urban space, psychological and structural aspects are important, as well as social use. Social use however is most important, because open urban space and its green surfaces satisfies needs of an urban population. The psychological aspect applies to direct experiencing and perception of space, while the structural aspect proves that public urban places are an important category in the urban structure. On the example of Bevk square, Nova Gorica, three types of analyses were carried out. With the structural analysis and evaluation, development and structure of the place were shown, its problems and qualities. The survey on public opinion utilised the method of cognitive mapping, enabled definition of the image of the square, as perceived by everyday users. With the method of time samples events on the square were observed, in different time slots and days of the week.

  15. Forced acoustical response of an open cavity coupled with a semi-infinite space

    CERN Document Server

    Tong, Yuhui; Pan, Jie

    2016-01-01

    This paper presents a study of the forced acoustical response of an open cavity from the perspective of modal expansion. Based on the coupled mode theory, it is shown that the sound pressure distribution of an open cavity excited by a point source placed within the cavity can be expanded by a set of frequency-dependent eigenmodes, which are derived from the coupling between the cavity and a semi-infinite space. The calculation of the acoustical responses for baffled and unbaffled open cavities indicates that the proposed modal expansion converges with only a few frequency-dependent eigenmodes in the frequency range of interest. The results of this study eliminate the ambiguity involving the selection of appropriate basis functions, in modal expansion for the forced response problem in open cavities.

  16. An open plus nonlinear closed loop control of chaotic oscillators

    Institute of Scientific and Technical Information of China (English)

    陈立群

    2002-01-01

    An open plus nonlinear closed loop control law is presented for chaotic oscillations described by a set of non-autonomous second-order ordinary differential equations. It is proven that the basins of entrainment are global whenthe right-hand sides of the equations are given by arbitrary polynomial functions. The forced Duffing oscillator and theforced van der Pol oscillator are treated as numerical examples to demonstrate the applications of the method.

  17. The Modeling Strategies for Open Software Architecture of Robot Controller

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Although the modeling technologies for open robot controllers have been discussed widely, not much literature is devoted to the actual general modeling principles and strategies. The reason is that many researches focus on specific application fields. This paper accommodates for this lacuna and provides some general modeling principles and strategies. At last, the actual new modeling method -Hierarchical Object-Oriented Petri net (HOONet) which has been proved to be an effective modeling methodology, is used to illustrate the modeling strategies.

  18. Public open spaces of small centralised settlements: Researching the typology of public open spaces and their occurrence in the area of Slovenia

    Directory of Open Access Journals (Sweden)

    Mia Crnič

    2014-10-01

    Full Text Available The area of Slovenia is rather widely intertwined with a network of centralised areas of various hierarchies. Several researchers (Drozg, Ravbar, Vrišer, Fister, and many others, who used a variety of input data and received adequate results, have been dealing with the topic of the influence of centres, their connections and characteristics. For a settlement to exist, it has to possess a program for the provision of its citizens. At the same time such a settlement has its own characteristics and ingredients at the level of the design of the settlement as well as construction. Fister (1993 dealt with the latter topic while Vrišer (1998 focused on the functionality of settlements and their influence on the catchment areas. In this context the question arises as to whether there is a connection between the categorisation of the Slovenian area in regards to the characteristics of construction by Fister and classification in regards to the program, its importance and the question whether classification criteria exists which could be connected into larger rounded off units with similar characteristics in regards to the building and similar program characteristics of public open spaces by Vrišer. The basis for researching the problem in question was the comparison of the model by Fister with the model by Vrišer. Acquired results formed the basis for further research of public open spaces connecting constructions in settlements with centres of second level by Vrišer.

  19. Space shuttle digital flight control system

    Science.gov (United States)

    Minott, G. M.; Peller, J. B.; Cox, K. J.

    1976-01-01

    The space shuttle digital, fly by wire, flight control system presents an interesting challenge in avionics system design. In residence in each of four redundant general purpose computers at lift off are the guidance, navigation, and control algorithms for the entire flight. The mission is divided into several flight segments: first stage ascent, second stage ascent; abort to launch site, abort once around; on orbit operations, entry, terminal area energy management; and approach and landing. The FCS is complicated in that it must perform the functions to fly the shuttle as a boost vehicle, as a spacecraft, as a reentry vehicle, and as a conventional aircraft. The crew is provided with both manual and automatic modes of operations in all flight phases including touchdown and rollout.

  20. Multiple model-informed open-loop control of uncertain intracellular signaling dynamics.

    Directory of Open Access Journals (Sweden)

    Jeffrey P Perley

    2014-04-01

    Full Text Available Computational approaches to tune the activation of intracellular signal transduction pathways both predictably and selectively will enable researchers to explore and interrogate cell biology with unprecedented precision. Techniques to control complex nonlinear systems typically involve the application of control theory to a descriptive mathematical model. For cellular processes, however, measurement assays tend to be too time consuming for real-time feedback control and models offer rough approximations of the biological reality, thus limiting their utility when considered in isolation. We overcome these problems by combining nonlinear model predictive control with a novel adaptive weighting algorithm that blends predictions from multiple models to derive a compromise open-loop control sequence. The proposed strategy uses weight maps to inform the controller of the tendency for models to differ in their ability to accurately reproduce the system dynamics under different experimental perturbations (i.e. control inputs. These maps, which characterize the changing model likelihoods over the admissible control input space, are constructed using preexisting experimental data and used to produce a model-based open-loop control framework. In effect, the proposed method designs a sequence of control inputs that force the signaling dynamics along a predefined temporal response without measurement feedback while mitigating the effects of model uncertainty. We demonstrate this technique on the well-known Erk/MAPK signaling pathway in T cells. In silico assessment demonstrates that this approach successfully reduces target tracking error by 52% or better when compared with single model-based controllers and non-adaptive multiple model-based controllers. In vitro implementation of the proposed approach in Jurkat cells confirms a 63% reduction in tracking error when compared with the best of the single-model controllers. This study provides an experimentally

  1. Multiple model-informed open-loop control of uncertain intracellular signaling dynamics.

    Science.gov (United States)

    Perley, Jeffrey P; Mikolajczak, Judith; Harrison, Marietta L; Buzzard, Gregery T; Rundell, Ann E

    2014-04-01

    Computational approaches to tune the activation of intracellular signal transduction pathways both predictably and selectively will enable researchers to explore and interrogate cell biology with unprecedented precision. Techniques to control complex nonlinear systems typically involve the application of control theory to a descriptive mathematical model. For cellular processes, however, measurement assays tend to be too time consuming for real-time feedback control and models offer rough approximations of the biological reality, thus limiting their utility when considered in isolation. We overcome these problems by combining nonlinear model predictive control with a novel adaptive weighting algorithm that blends predictions from multiple models to derive a compromise open-loop control sequence. The proposed strategy uses weight maps to inform the controller of the tendency for models to differ in their ability to accurately reproduce the system dynamics under different experimental perturbations (i.e. control inputs). These maps, which characterize the changing model likelihoods over the admissible control input space, are constructed using preexisting experimental data and used to produce a model-based open-loop control framework. In effect, the proposed method designs a sequence of control inputs that force the signaling dynamics along a predefined temporal response without measurement feedback while mitigating the effects of model uncertainty. We demonstrate this technique on the well-known Erk/MAPK signaling pathway in T cells. In silico assessment demonstrates that this approach successfully reduces target tracking error by 52% or better when compared with single model-based controllers and non-adaptive multiple model-based controllers. In vitro implementation of the proposed approach in Jurkat cells confirms a 63% reduction in tracking error when compared with the best of the single-model controllers. This study provides an experimentally

  2. Control of Open Contour Formations of Autonomous Underwater Vehicles

    Directory of Open Access Journals (Sweden)

    Uwe Zimmer

    2008-11-01

    Full Text Available In this paper, we propose a distributed elastic behaviour for a deformable chain-like formation of small autonomous underwater vehicles with the task of forming special shapes which have been explicitly defined or are defined by some iso-contour of an environmental concentration field. In the latter case, the formation has to move in such a way as to meet certain formation parameters as well as adapt to the iso-line. We base our controller on our previous models (for manually controlled end points using general curve evolution theory but will also propose appropriate motions for the end robots of an open chain.

  3. Scaffolding open inquiry: How a teacher provides students with structure and space

    Directory of Open Access Journals (Sweden)

    Birgitte Bjønness

    2015-11-01

    Full Text Available The present case study examines a teacher’s scaffolding strategies supporting his students during a twelve-week open inquiry project at an upper secondary school. We use interaction analysis to identify how he provides structure and space in the different phases of open inquiry as well as how it constitutes the students’ inquiry process. The study reveals that the teacher scaffolded this open inquiry in two opposing ways; he created space for the students to make their own experiences and ideas, which eventually set up the need for more directed scaffolding to discuss the challenges students experienced, and directing students’ ideas in certain directions in phases with structure. We suggest that the interplay between structure and space creates what can be seen as a driving force providing both exploration and direction for open inquiry. Moreover, we propose that the dual concept of ‘structure and space’ can work as a thinking tool to promote teachers’ competence on how to scaffold more authentic versions of scientific inquiry in schools.

  4. Federated Space-Time Query for Earth Science Data Using OpenSearch Conventions

    Science.gov (United States)

    Lynnes, C.; Beaumont, B.; Duerr, R. E.; Hua, H.

    2009-12-01

    The past decade has seen a burgeoning of remote sensing and Earth science data providers, as evidenced in the growth of the Earth Science Information Partner (ESIP) federation. At the same time, the need to combine diverse data sets to enable understanding of the Earth as a system has also grown. While the expansion of data providers is in general a boon to such studies, the diversity presents a challenge to finding useful data for a given study. Locating all the data files with aerosol information for a particular volcanic eruption, for example, may involve learning and using several different search tools to execute the requisite space-time queries. To address this issue, the ESIP federation is developing a federated space-time query framework, based on the OpenSearch convention (www.opensearch.org), with Geo and Time extensions. In this framework, data providers publish OpenSearch Description Documents that describe in a machine-readable form how to execute queries against the provider. The novelty of OpenSearch is that the space-time query interface becomes both machine callable and easy enough to integrate into the web browser's search box. This flexibility, together with a simple REST (HTTP-get) interface, should allow a variety of data providers to participate in the federated search framework, from large institutional data centers to individual scientists. The simple interface enables trivial querying of multiple data sources and participation in recursive-like federated searches--all using the same common OpenSearch interface. This simplicity also makes the construction of clients easy, as does existing OpenSearch client libraries in a variety of languages. Moreover, a number of clients and aggregation services already exist and OpenSearch is already supported by a number of web browsers such as Firefox and Internet Explorer.

  5. Space Telescope precision pointing control system

    Science.gov (United States)

    Beals, G. A.; Crum, R. C.; Dougherty, H. J.; Hegel, D. K.; Kelley, J. L.

    1986-01-01

    The Hubble Space Telescope has the most stringent pointing requirements imposed on any spacecraft to date. The overall HST stability shall not exceed 0.007 arc-seconds rms. The Pointing Control System utilizes fine guidance sensors and rate gyros for attitude reference and rate information. Control torques are provided by reaction wheels. A digital computer collects the sensor data, performs the control law computations, and sends torque commands to the reaction wheels. To attain this precision pointing, improvements were made to the rate gyros to lower their noise characteristics and to the reaction wheels to reduce their emitted vibration levels. The control system design was validated in a test sequence which progressed from model verification tests on an air-bearing to operations-oriented, closed loop testing on the assembled vehicle. A test system is described which allowed the simultaneous production of test case command loads for the flight computer and plots of predicted profiles to assist in test data analysis. Workarounds were required during system test to accommodate gyro biases and noise introduced into the closed loop system. Testing and analysis indicate that the HST will provide the capability to meet the requirements for precision pointing.

  6. Agent Control for Reconfigurable Open Kinematic Chain Manipulators

    Directory of Open Access Journals (Sweden)

    Janez Sluga

    2013-10-01

    Full Text Available This paper presents a method for the autonomous control of differently structured open kinematic chains based on multi-agent system technology. The appropriate level of distributing local autonomy (agents to a manipulative structure is defined, which makes it possible to dynamically change the number, type and structure of manipulative components without modifying their behavioural logic. To achieve fast reconfigurable and scalable manipulative systems, a new multi-agent method is developed for controlling the manipulator kinematics. The new method enables independent manipulator structure from the control system because of its structural and system modularity. The proposed method consists of kinematic equations for use in an agent environment, agent motion-planning algorithms, evaluation functions, agent control logic and kinematic algorithms. The results of simulations and real- world experiments demonstrate the usefulness of the approach for different non-redundant and redundant manipulation structures.

  7. Planning open spaces for Biodiversity: Evaluating Urban Parks for Wildlife Habitat

    Directory of Open Access Journals (Sweden)

    Margaret Livingston

    2004-06-01

    Full Text Available Natural open spaces adjacent to developing cities are frequently affected by advancing urban sprawl. It requires a delicate balancing act to conserve habitats while developing new environments for city inhabitants. As landscape architects, planners, and managers of these areas, we continue to explore mitigation strategies for habitats affected by development. One strategy focuses on creating new spaces within development that can fulfil some of the functions previously provided by natural areas and serve as resource links among remaining peripheral natural areas (Forman and Godron, 1986. Previous research has shown that created open spaces, such as parks and golf courses may provide critical habitat functions associated with natural areas if planned appropriately (Mannan and Boal, 2000; Shaw et al, 1998. However, few studies have evaluated the specific characteristics associated with created open spaces for their wildlife habitat value. This research addresses the following question: What is the potential habitat value of current vegetation in urban parks in Tucson, Arizona? The goals of this study were to: 1 evaluate potential habitat value of urban parks using a wildlife habitat value index (Shaw et al, 1998, and 2 provide recommendations emphasising increased biodiversity through habitat development in these open spaces. Most vegetation in the surveyed parks was non-native and provided little escape cover for wildlife. Plant species richness and abundance were relatively low in most parks, but higher for sites where existing native vegetation was incorporated into the park. Recommendations emphasise: 1 appropriate arrangement and placement of species based on functions required by human and wildlife users; 2 increased horizontal and vertical vegetation layers; 3 design focus on regional plant communities; and 4 development of written specifications for parks that address design uses of native species and their maintenance.

  8. Scientific competency questions as the basis for semantically enriched open pharmacological space development

    DEFF Research Database (Denmark)

    Azzaoui, Kamal; Jacoby, Edgar; Senger, Stefan

    2013-01-01

    (IMI) Open PHACTS consortium for the design of an open pharmacological space (OPS) information system. The focus of this work is the integration of compound–target–pathway–disease/phenotype data for public and industrial drug discovery research. Typical scientific competency questions provided......Molecular information systems play an important part in modern data-driven drug discovery. They do not only support decision making but also enable new discoveries via association and inference. In this review, we outline the scientific requirements identified by the Innovative Medicines Initiative...

  9. OpenRRArch: An open, robust and reliable architecture for controlling autonomous robots

    Directory of Open Access Journals (Sweden)

    Fredy Hernán Martínez Sarmiento

    2017-01-01

    Full Text Available Context: The control and navigation systems of autonomous robots constitute a dynamic field of research in robotics. The possible solutions to problems are often evaluated with laboratory prototypes in order to determine their real performance. We propose in this paper an architecture for the design and development of robotic systems (particularly autonomous multi-robot Systems that facilitate the work in laboratory due to an open robust and reliable architecture. Method: The architecture is supported in open source hardware and software. The operation and communication strategy is characterized by a low consumption of resources, both in processing and communication, and real-time operation. As developement platform and Operating System, we used Linux: the communication scheme and the embedded systems run on a 32-bit processor, with a 16-bit instruction set (not ARM, but with Harvard architecture, at 80 MHz (Tensilica Xtensa LX106 for the implementation of the agents. The tools used allow the solution to be bothe efficient and inexpensive. Results: The architecture has been successfully applied in the implementation of a strategy of navigation for a set of small autonomous robots. A set of robots were provided with wireless communication capability, minimum capacity of environmental sensing (obstacle detection and a navigation algorithm based on population sizes (mimicking the bacterial Quorum Sensing. The system is implemented with great ease, demonstrating both the viability of the navigation strategy and the versatility, robustness and scalability of the OpenRRArch architecture. Conclusions: The proposed architecture constitutes a solution for the construction of distributed control systems, in particular multi-agent robotic systems. It enables the rapid, low-cost and high-performance implementation of systems with real-time cooperation and communication capabilities. The architecture allows the integration of agents with different processing

  10. Applied Joint-Space Torque and Stiffness Control of Tendon-Driven Fingers

    Science.gov (United States)

    Abdallah, Muhammad E.; Platt, Robert, Jr.; Wampler, Charles W.; Hargrave, Brian

    2010-01-01

    Existing tendon-driven fingers have applied force control through independent tension controllers on each tendon, i.e. in the tendon-space. The coupled kinematics of the tendons, however, cause such controllers to exhibit a transient coupling in their response. This problem can be resolved by alternatively framing the controllers in the joint-space of the manipulator. This work presents a joint-space torque control law that demonstrates both a decoupled and significantly faster response than an equivalent tendon-space formulation. The law also demonstrates greater speed and robustness than comparable PI controllers. In addition, a tension distribution algorithm is presented here to allocate forces from the joints to the tendons. It allocates the tensions so that they satisfy both an upper and lower bound, and it does so without requiring linear programming or open-ended iterations. The control law and tension distribution algorithm are implemented on the robotic hand of Robonaut-2.

  11. Access to the parapharyngeal space: an anatomical study comparing the endoscopic and open approaches.

    Science.gov (United States)

    Van Rompaey, Jason; Suruliraj, Anand; Carrau, Ricardo; Panizza, Benedict; Solares, C Arturo

    2013-10-01

    A subtemporal preauricular approach to the infratemporal fossa and parapharyngeal space has been the traditional path to tumors of this region. The morbidity associated with this procedure has lead to the pursuit of less invasive techniques. Endoscopic access using a minimally invasive transmaxillary/transpterygoid approach potentially may obviate the drawbacks associated with open surgery. The anatomy of the parapharyngeal space is complex and critical; therefore, a comparison of the anatomy exposed by these different approaches could aid in the decision making toward a minimally invasive surgical corridor. Technical Note. The parapharyngeal space was accessed endonasally by removal of the medial and posterior walls of the maxillary sinus. To allow better visualization and increased triangulation of a bimanual dissection technique, a sublabial canine fossa antrostomy was created. The medial and lateral pterygoid plates were removed. Further lateral dissection exposed the relevant anatomy of the parapharyngeal space. A subtemporal preauricular infratemporal approach was also completed. The endoscopic approach provided sufficient access to the superior portion of the parapharyngeal space. The open approach also provided adequate access; however, it required a larger surgical window, causing greater injury. A significant advantage of the subtemporal approach is the improved access to the petrous portion of the internal carotid artery. Conversely, the endonasal approach provided improved access to the anterior and medial portions of the superior parapharyngeal space. Endoscopic endonasal access utilizing a transmaxillary/transpterygoid approach provides a sufficient surgical window for tumor extirpation. Utilization of this approach obviates some of the morbidity associated with an open procedure. 5. Copyright © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

  12. Developing the urban blue: Comparative health responses to blue and green urban open spaces in Germany.

    Science.gov (United States)

    Völker, Sebastian; Kistemann, Thomas

    2015-09-01

    Recently, new perspectives upon healthy urban open spaces propose that open spaces can be regarded as urban green or blue spaces. However, there has so far been very little research into blue environments and their benefits for mental well-being. Our article focuses on the effects of water in cities, "urban blue" (as compared to "urban green"), on human health and well-being. To assess the mental well-being of visitors, we conducted qualitative semi-standardised interviews (n=113), asking which differences in well-being occur when visiting urban green and blue spaces in high-density areas of the inner city in Dusseldorf and Cologne, Germany. Although we found many similarities, some health-enhancing effects for users turned out to be prominent for urban blue in the four conceptual therapeutic landscape dimensions: experienced, symbolic, social and activity space. These effects include enhanced contemplation, emotional bonding, participation, and physical activity. The results suggest that urban blue as a health-promoting factor needs more detailed and accurate determination and examination of its general and local health-enhancing effects.

  13. B -> tau nu: Opening up the Charged Higgs Parameter Space with R-parity Violation

    CERN Document Server

    Bose, Roshni

    2011-01-01

    The theoretically clean channel B+ -> tau+ nu shows a close to 3sigma discrepancy between the Standard Model prediction and the data. This in turn puts a strong constraint on the parameter space of a two-Higgs doublet model, including R-parity conserving supersymmetry. The constraint is so strong that it almost smells of fine-tuning. We show how the parameter space opens up with the introduction of suitable R-parity violating interactions, and release the tension between data and theory.

  14. GeneLab: NASA's Open Access, Collaborative Platform for Systems Biology and Space Medicine

    Science.gov (United States)

    Berrios, Daniel C.; Thompson, Terri G.; Fogle, Homer W.; Rask, Jon C.; Coughlan, Joseph C.

    2015-01-01

    NASA is investing in GeneLab1 (http:genelab.nasa.gov), a multi-year effort to maximize utilization of the limited resources to conduct biological and medical research in space, principally aboard the International Space Station (ISS). High-throughput genomic, transcriptomic, proteomic or other omics analyses from experiments conducted on the ISS will be stored in the GeneLab Data Systems (GLDS), an open-science information system that will also include a biocomputation platform with collaborative science capabilities, to enable the discovery and validation of molecular networks.

  15. A methodology for the evaluation of the human-bioclimatic performance of open spaces

    Science.gov (United States)

    Charalampopoulos, Ioannis; Tsiros, Ioannis; Chronopoulou-Sereli, Aik.; Matzarakis, Andreas

    2016-02-01

    The purpose of this paper is to present a simple methodology to improve the evaluation of the human-biometeorological benefits of open spaces. It is based on two groups of new indices using as basis the well-known PET index. This simple methodology along with the accompanying indices allows a qualitative and quantitative evaluation of the climatic behavior of the selected sites. The proposed methodology was applied in a human-biometeorology research in the city of Athens, Greece. The results of this study are in line with the results of other related studies indicating the considerable influence of the sky view factor (SVF), the existence of the vegetation and the building material on human-biometeorological conditions. The proposed methodology may provide new insights in the decision-making process related to urban open spaces' best configuration.

  16. 100 Most Cited Articles in Urban Green and Open Spaces: A Bibliometric Analysis

    OpenAIRE

    Mehdi Rakhshandehroo; Mohd Johari Mohd Yusof; Nader Ale Ebrahim; Ali Sharghi; Roozbeh Arabi

    2015-01-01

    Researchers have contributed significantly to the development of the subject of urban green and open spaces (UGOS) in both practical and fundamental aspects. As the number of citations indicates a paper and author’s competency, the online web of science (ISI) was browsed to identify the 100 most cited papers in the field of UGOS from 1980 to 2013. Papers were analyzed for authorship, journal sources, publishers, institutions, countries, year of publication, categories, and author keywords. Th...

  17. Modular Open System Architecture for Reducing Contamination Risk in the Space and Missile Defense Supply Chain

    Science.gov (United States)

    Seasly, Elaine

    2015-01-01

    To combat contamination of physical assets and provide reliable data to decision makers in the space and missile defense community, a modular open system architecture for creation of contamination models and standards is proposed. Predictive tools for quantifying the effects of contamination can be calibrated from NASA data of long-term orbiting assets. This data can then be extrapolated to missile defense predictive models. By utilizing a modular open system architecture, sensitive data can be de-coupled and protected while benefitting from open source data of calibrated models. This system architecture will include modules that will allow the designer to trade the effects of baseline performance against the lifecycle degradation due to contamination while modeling the lifecycle costs of alternative designs. In this way, each member of the supply chain becomes an informed and active participant in managing contamination risk early in the system lifecycle.

  18. Open space anxiety test in rodents: the elevated platform with steep slopes.

    Science.gov (United States)

    Ennaceur, Abdelkader

    2012-01-01

    This report describes a behavioral test protocol for assessing anxiety in mice and rats in single or multiple sessions. The test is based on exposure of animals to an open-space elevated platform with suspended steep slopes attached on two opposite sides. In this test, all animals cross frequently onto and spend more time in the areas adjacent to slopes than in the areas adjacent to a void space. Balb/c mice (albinos) were shown consistently to be more anxious than CD-1 mice (albinos), c57/Bl6J and c57/Bl6N (pigmented) mice; they do not cross onto the slopes. When Balb/c mice are treated with amphetamine or diazepam, the number of crossings on the platform is significantly increased but only diazepam-treated mice do cross onto the slopes. In the presence of a protected space on the platform, the behavior of c57/Bl6J compares to that of Balb/c mice; they stop crossings onto the slopes and demonstrate avoidance response. Unlike the current existing tests, the present open-space anxiety test demonstrates reliable and consistent results with strong construct and discriminant validity. It provides unequivocal measures of fear-induced anxiety, which are not confounded with measures of fear-induced escape/avoidance responses, hyperactivity or impulsive responses.

  19. A public hedonic analysis of environmental attributes in an open space preservation program

    Science.gov (United States)

    Nordman, Erik E.

    The Town of Brookhaven, on Long Island, NY, has implemented an open space preservation program to protect natural areas, and the ecosystem services they provide, from suburban growth. I used a public hedonic model of Brookhaven's open space purchases to estimate implicit prices for various environmental attributes, locational variables and spatial metrics. I also measured the correlation between cost per acre and non-monetary environmental benefit scores and tested whether including cost data, as opposed to non-monetary environmental benefit score alone, would change the prioritization ranks of acquired properties. The mean acquisition cost per acre was 82,501. I identified the key on-site environmental and locational variables using stepwise regression for four functional forms. The log-log specification performed best ( R2adj= 0.727). I performed a second stepwise regression (log-log form) which included spatial metrics, calculated from a high-resolution land cover classification, in addition to the environmental and locational variables. This markedly improved the model's performance ( R2adj=0.866). Statistically significant variables included the property size, location in the Pine Barrens Compatible Growth Area, location in a FEMA flood zone, adjacency to public land, and several other environmental dummy variables. The single significant spatial metric, the fractal dimension of the tree cover class, had the largest elasticity of any variable. Of the dummy variables, location within the Compatible Growth Area had the largest implicit price (298,792 per acre). The priority rank for the two methods, non-monetary environmental benefit score alone and the ratio of non-monetary environmental benefit score to acquisition cost were significantly positively correlated. This suggests that, despite the lack of cost data in their ranking method, Brookhaven does not suffer from efficiency losses. The economics literature encourages using both environmental benefits and

  20. Transanal opening of intersphincteric space (TROPIS) - A new procedure to treat high complex anal fistula.

    Science.gov (United States)

    Garg, Pankaj

    2017-04-01

    The sepsis in intersphincteric space has important role in pathogenesis of most complex fistula-in-ano. This sepsis is like a small abscess in a closed space. This closed space needs to be drained adequately and then kept open for the fistula-in-ano to heal properly. The aim was to lay open and drain the intersphincteric space through internal opening via transanal approach. This has been tried in submucosal and intersphincteric rectal abscesses but has never been tried in complex fistula-in-ano. All consecutive patients of complex high (involving >1/3 of sphincter complex) fistula-in-ano who were operated were included in the prospective cohort study. Preoperative MRI scan was done in all the patients. Transanal laying open of the intersphincteric space (TROPIS) was done through the internal opening. The external sphincter was not cut. The tracts in the ischiorectal fossa were curetted and cleaned. The incontinence scores were measured. 61 patients with high complex fistula-in-ano were included (follow-up:6-21 months). Male/Female:59/2, age-42.3 ± 9.5 years. 85.2% (52) were recurrent, 83.6% (51) had multiple tracts, 36.1% (22) had horseshoe tract, 34.4% (21) had supralevator extension and 26.2% (16) had associated abscess. 95.1% (58) were posterior fistula out of which 90.2% (55) were in posterior midline. Nine patients were excluded (due to tuberculosis, lost to follow-up). Fistula healed completely in 84.6% (44/52) and didn't heal in 15.4% (9/52). 4/9 of these were reoperated and fistula healed in three patients. Thus overall healing rate was 90.4% (47/52). There was no significant change in incontinence scores. TROPIS is a simple effective sphincter sparing procedure to treat high complex fistula-in-ano including supralevator and horseshoe fistula. Copyright © 2017 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

  1. Bursting into space: alterations of sympathetic control by space travel

    Science.gov (United States)

    Eckberg, D. L.

    2003-01-01

    AIM: Astronauts return to Earth with reduced red cell masses and hypovolaemia. Not surprisingly, when they stand, their heart rates may speed inordinately, their blood pressures may fall, and some may experience frank syncope. We studied autonomic function in six male astronauts (average +/- SEM age: 40 +/- 2 years) before, during, and after the 16-day Neurolab space shuttle mission. METHOD: We recorded electrocardiograms, finger photoplethysmographic arterial pressures, respiration, peroneal nerve muscle sympathetic activity, plasma noradrenaline and noradrenaline kinetics, and cardiac output, and we calculated stroke volume and total peripheral resistance. We perturbed autonomic function before and during spaceflight with graded Valsalva manoeuvres and lower body suction, and before and after the mission with passive upright tilt. RESULTS: In-flight baseline sympathetic nerve activity was increased above pre-flight levels (by 10-33%) in three subjects, in whom noradrenaline spillover and clearance also were increased. Valsalva straining provoked greater reductions of arterial pressure, and proportionally greater sympathetic responses in space than on Earth. Lower body suction elicited greater increases of sympathetic nerve activity, plasma noradrenaline, and noradrenaline spillover in space than on Earth. After the Neurolab mission, left ventricular stroke volume was lower and heart rate was higher during tilt, than before spaceflight. No astronaut experienced orthostatic hypotension or pre-syncope during 10 min of post-flight tilting. CONCLUSION: We conclude that baseline sympathetic outflow, however measured, is higher in space than on earth, and that augmented sympathetic nerve responses to Valsalva straining, lower body suction, and post-flight upright tilt represent normal adjustments to greater haemodynamic stresses associated with hypovolaemia.

  2. IR image generation of space target based on OpenGL

    Science.gov (United States)

    Shen, Tongsheng; Guo, Ming; Wang, Chenggang

    2007-11-01

    IR Scene simulation has been an important way to design and assess the IR sensor, and the key of simulation is the generation of IR scene image. Based on OpenGL, the method of IR image generation is proposed. The geometry model is constructed with professional CAD software, and the observer location is determined after scene transformation. The full infrared model of space target is built based on infrared physics and heat transfer, which includes the radiation, convection, conduction between different parts of the space target, and which also includes the radiation, convection of environment. Radiance of space target is converted to gray value, and properties of scene are defined according to the gray level. After a series of processing, dynamic IR images are generated with the technology of double buffering.

  3. Open modular architecture controls at GM Powertrain: technology and implementation

    Science.gov (United States)

    Bailo, Clark P.; Yen, C. J.

    1997-01-01

    General Motors Powertrain Group (GMPTG) has been the leader in implementing open, modular architecture controller (OMAC) technologies in its manufacturing applications since 1986. The interest in OMAC has been greatly expanded for the past two years because of the advancement of personal computer technologies and the publishing of the OMAC whitepaper by the US automotive companies stating the requirements of OMAC technologies in automotive applications. The purpose of this paper is to describe the current OMAC projects and the future direction of implementation at GMPTG. An overview of the OMAC project and the definition of the OMAC concept are described first. The rationale of pursuing open technologies is explained from the perspective of GMPTG in lieu of its agile manufacturing strategy. Examples of existing PC-based control applications are listed to demonstrate the extensive commitment to PC-based technologies that has already been put in place. A migration plan form PC-based to OMAC-based systems with the thorough approach of validation are presented next to convey the direction that GMPTG is taking in implementing OMAC technologies. Leveraged technology development projects are described to illustrate the philosophy and approaches toward the development of OMAC technologies at GMPTG. Finally, certain implementation issues are discussed to emphasize efforts that are still required to have successful implementations of OMAC systems.

  4. Open architecture controller solution for custom machine systems

    Science.gov (United States)

    Anderson, Ronald L.; Reagin, J. M.; Garner, T. D.; Sweeny, T. E.

    1997-01-01

    In today's marketplace, product quality and price have become requirements for entry and are no longer sufficient to differentiate one's product and gain a competitive advantage. A key to competition in the future will be a company's ability to respond quickly to a rapidly-changing global marketplace. Developers of manufacturing equipment must play a role in the reduction of the product development cycle time by increasing the flexibility of their equipment and decreasing its cost and time to market. This paper will discuss the implementation of an open-architecture machine controller on a flip-chip placement machine and how this implementation supports the goals of reduced development time and increased equipment flexibility. The following subjects are discussed: 1) Issues related to the selection of a standard operating system, including real-time performance, preemptive multi-tasking, multi-threaded applications, and development tools. 2) The use of a common API for motion, and I/O. 3) Use of a rapid application development and object-oriented programming techniques on the machine controller to shorten development time and support code reuse. 4) Specific hardware and software issues related to the implementation of the flip chip controller. This includes hardware and software implementation details, controller performance, and human interface issues.

  5. DAYLIGHTING PERFORMANCE OF HORIZONTAL LIGHT PIPE BRANCHING ON OPEN PLAN OFFICE SPACE

    Directory of Open Access Journals (Sweden)

    Feny ELSIANA

    2015-12-01

    Full Text Available For daylighting purpose, office buildings should have a shallow plan and increase the ratio of surface to building’s volume. However, intensive use of air-conditioning drives office building’s plan to be deep with a minimum surface to volume ratio. This leads to the presence of areas that have insufficient daylight level at the work plane. Considering limitations of some daylighting methods in distributing daylight to these areas, Horizontal Light Pipe (HLP was selected. The aim of this research was to evaluate and explain the effect of HLP branching on daylight quantity and distribution inside open plan office space. Experimental with simulation as a tool was used as the research method. HLP branching’s uniformity ratio, illuminance and Daylight Factor were compared with unbranching HLP, simultaneously with daylighting standards. Results showed that office space with HLP-L branching had higher daylight level than HLP-T branching, 296 lux and 295 lux, HLP-L and HLP-T, respectively. However, HLP-T branching distributed daylight more evenly than HLP-L branching, with uniformity ratio as 1.49:1 and 1.50:1, HLP-T and HLP-L, respectively. Both of them met the illuminance target value and uniformity at work plane. Light’s deflection and improvement amount of opening distribution decreased average illuminance and Daylight Factor up to 3.59%. Those also decreased uniformity of daylight inside the space.

  6. Thermal Performance of Housing Open Spaces in the City of Mosul

    Directory of Open Access Journals (Sweden)

    Dr. TURKI HASAN ALI ALHADIDI

    2012-03-01

    Full Text Available The rapid urban growth has lead to an urgent need to increase residential buildings in such a way that requires quick execution of such buildings. The appearance of modern materials such as reinforced concrete has helped in getting fast-constructed houses of a westerly pattern such that excluding the inherited styles that are in harmony with severe environment like that of the Middle East. This has resulted in a modern pattern of buildings lacks the microclimate which was enjoyed by the traditional pattern and which have provided the inhabitant with a relative thermal comfort. ‎This research try to compare different microclimates due to the variation of open architectural spaces patterns in the residential units (traditional ones represented by (the courtyards and Iwan and the modem one represented by the space of (garages and terraces in Summer in Mosul city. ‎ ‎The results showed that the traditional open spaces are the nearest to the thermal comfort zone, although both of them don't represent the ideal state of human comfort in this ‎period of Summer.

  7. Metacognitive Control and the Spacing Effect

    Science.gov (United States)

    Son, Lisa K.

    2010-01-01

    This study investigates whether the use of a spacing strategy absolutely improves final performance, even when the learner had chosen, metacognitively, to mass. After making judgments of learning, adult and child participants chose to mass or space their study of word pairs. However, 1/3 of their choices were dishonored. That is, they were forced…

  8. Clifford algebra-valued orthogonal polynomials in the open unit ball of Euclidean space

    Directory of Open Access Journals (Sweden)

    Fred Brackx

    2004-01-01

    Full Text Available A new method for constructing Clifford algebra-valued orthogonal polynomials in the open unit ball of Euclidean space is presented. In earlier research, we only dealt with scalar-valued weight functions. Now the class of weight functions involved is enlarged to encompass Clifford algebra-valued functions. The method consists in transforming the orthogonality relation on the open unit ball into an orthogonality relation on the real axis by means of the so-called Clifford-Heaviside functions. Consequently, appropriate orthogonal polynomials on the real axis give rise to Clifford algebra-valued orthogonal polynomials in the unit ball. Three specific examples of such orthogonal polynomials in the unit ball are discussed, namely, the generalized Clifford-Jacobi polynomials, the generalized Clifford-Gegenbauer polynomials, and the shifted Clifford-Jacobi polynomials.

  9. Real-time control open systems of five DOF nanomanipulators

    Science.gov (United States)

    Vladareanu, Luige; Vasile, Alexandru

    2010-11-01

    The main paper presents studies and research concerning the development of new open architectures for real-time control of a 5 degrees of freedom platform with 4 nano-manipulators, based on multiprocessor systems operating in a cooperation regime in order to achieve experiments in the 4 research domains: robotics, vibro-acustica, tribology, carbon nano tubes (CNTs ). In order to obtain this performance a positioning method with high precision at high speed is developed through reducing and compensating the induced dynamic vibrations by the system movement using the inverse dynamics method. The system's performance will allow the introduction of new functions without significant change to the hardware system. Through determining the optimal trajectory using a quadratic cost function for reducing tracking errors results increased motion speed and micro or nanometric positioning precision.

  10. Grassland communities of urban open spaces in Bloemfontein, Free State, South Africa

    Directory of Open Access Journals (Sweden)

    Mamokete N.V. Dingaan

    2013-02-01

    Full Text Available Natural vegetation in urban environments is greatly impacted by human activities and it is in constant threat of degradation and destruction as a result of urbanisation. This vegetation, although fragmented, serves an important ecological function and needs to be properly managed and conserved. Studies on urban vegetation are lacking in South Africa, with only a handful having been carried out since the end of the last century. This study was initiated to identify, classify and describe the grassland communities of the urban open spaces in Bloemfontein. Relevés were compiled in 61 sample plots, where species present and habitat information were recorded. Care was taken to restrict sample plots to vegetation in pristine condition, wherever possible, and severely degraded stands were avoided. A two-way indicator species analysis (TWINSPAN classification, refined by Braun-Blanquet procedures, revealed two distinct major communities, seven communities and four sub-communities. Both detrended and canonical correspondence analyses indicated the vegetation units to be associated with soil texture and pH, although biotic factors such as overgrazing, burning and mowing also influence the composition of the vegetation. The proper management and conservation of urban open spaces requires in-depth knowledge of the spatial distribution, floristic, structural and functional compositions within the major vegetation types in this environment. The present study further contributed towards formulating ways for the proper management, utilisation and functioning of the open spaces within the Bloemfontein area.Conservation implications: The Grassland Biome of South Africa is poorly conserved, mainly because of its status as an agricultural hub of the country. The preservation of natural and semi-natural forms of urban vegetation is important because such vegetation, although often disturbed and degraded, could form dispersal corridors between peri-urban and rural

  11. All conjugate-maximal-helicity-violating amplitudes from topological open string theory in twistor space.

    Science.gov (United States)

    Roiban, Radu; Volovich, Anastasia

    2004-09-24

    It has recently been proposed that the D-instanton expansion of the open topological B model on P(3|4) is equivalent to the perturbative expansion of the maximally supersymmetric Yang-Mills theory in four dimensions. In this letter we show how to construct the gauge theory results for all n-point conjugate-maximal-helicity-violating amplitudes by computing the integral over the moduli space of curves of degree n-3 in P(3|4), providing strong support to the string theory construction.

  12. Open Discussion Session: Challenges and Advancements in Coordinated Space Weather Activities

    Science.gov (United States)

    Kauristie, Kirsti

    2016-07-01

    Besides addressing the key questions in space weather research the Cospar/ILWS Roadmap presents also recommendations for teaming in the research environment and for collaboration between agencies and communities. Coordinated work of different research groups facilitate our efforts for a holistic view on the entire Sun-Earth system with its complicated feedback processes in different scale sizes. Seamless knowledge transfer from research to operational services is a crucial factor for the success of space weather research field. In this open discussion session we encourage the participants to share their views on most important challenges and advancements in our field, both in science and in collaboration. We also welcome comments on the roadmap recommendations and guidance for similar activities in the future.

  13. What Attracts People to Visit Community Open Spaces? A Case Study of the Overseas Chinese Town Community in Shenzhen, China

    Directory of Open Access Journals (Sweden)

    Yiyong Chen

    2016-06-01

    Full Text Available A well-designed open space that encourages outdoor activity and social communication is a community asset that could potentially contribute to the health of local residents and social harmony of the community. Numerous factors may influence the use of each single space and may result in a variety of visitors. Compared with previous studies that focused on accessibility, this study highlights the relationship between the utilization and characteristics of community open spaces in China. The Overseas Chinese Town community in Shenzhen is regarded as an example. The association between the number of visitors and space characteristics is examined with multivariate regression models. Results show that large areas with accessible lawns, well-maintained footpaths, seats, commercial facilities, and water landscapes are important characteristics that could increase the use of community open spaces. However, adding green vegetation, sculptures, and landscape accessories in open spaces has limited effects on increasing the outdoor activities of residents. Thus, to increase the use of community open spaces, landscape designers should focus more on creating user-oriented spaces with facilities that encourage active use than on improving ornamental vegetation and accessories.

  14. The Space Apps Challenge: Using Open Innovation Competitions to Engage The Public in the Scientific Process

    Science.gov (United States)

    Gupta, S. S.

    2016-12-01

    NASA's Space Apps Challenge encourages innovation, creativity and collaborative problem solving by gathering coders, builders, artists, designers, and storytellers in a 48-hour hackathon. Open Innovation competitions such as the Space Apps Challenge bring the scientific world to members of the public, regardless of age, experience, credentials, or expertise. In the past five years, this model of public engagement has been widely employed by government, nonprofit and academic institutions, allowing the building of partnerships between the scientific community and the individuals and communities they serve. Furthermore, advances in technology and challenge models have lowered the barriers and costs to scientific collaboration with and for the public. NASA's Space Apps Challenge, structured as a competition seeking solutions from the public to posed problems, brings together teams and forges collaborations between individuals and groups who would otherwise have never worked together for a short but high intensity problem solving session, Space Apps has has created a pathway to public engagement and innovation that is often faster, cheaper, and more impactful than traditional approaches.

  15. Opened athletic-educational space - the condition of professional development of future teacher of physical culture is needed

    Directory of Open Access Journals (Sweden)

    Dragnev Y.V.

    2012-04-01

    Full Text Available It is shown that the opening of the sports and educational space is determined by the whole space, where the interaction of the activity of the pedagogical university with different educational institutions on the basis of integration, continuity of the educational process, aimed at physical education, the development of children and young people take place. It is revealed the importance of awareness of such concepts as the world educational space, the international educational space, the European higher education area, European space of higher education and educational space of the CIS countries.

  16. asymptotics for open-loop window flow control

    Directory of Open Access Journals (Sweden)

    Arthur W. Berger

    1994-01-01

    Full Text Available An open-loop window flow-control scheme regulates the flow into a system by allowing at most a specified window size W of flow in any interval of length L. The sliding window considers all subintervals of length L, while the jumping window considers consecutive disjoint intervals of length L. To better understand how these window control schemes perform for stationary sources, we describe for a large class of stochastic input processes the asymptotic behavior of the maximum flow in such window intervals over a time interval [0,T] as T and Lget large, with T substantially bigger than L. We use strong approximations to show that when T≫L≫logT an invariance principle holds, so that the asymptotic behavior depends on the stochastic input process only via its rate and asymptotic variability parameters. In considerable generality, the sliding and jumping windows are asymptotically equivalent. We also develop an approximate relation between the two maximum window sizes. We apply the asymptotic results to develop approximations for the means and standard deviations of the two maximum window contents. We apply computer simulation to evaluate and refine these approximations.

  17. Factors Influencing Visitors to Suburban Open Space Areas near a Northern Japanese City

    Directory of Open Access Journals (Sweden)

    Yasushi Shoji

    2012-04-01

    Full Text Available Visitor information often serves as the basis for the management plan of parks. However, there exist few scientific and fundamental surveys for parks and open spaces in Japan. We analyzed the correlation between the number of visitors and the various factors in a suburban open space in a northern Japanese city, Takino Park. To explain the fluctuations in the number of visitors in Takino Park, multiple regression analyses with the stepwise method were conducted. The analyses employed social factors and meteorological factors, such as the day of the week, school vacations, temperature and the weather. The results show that the most influential factor is the day of the week, i.e., Sundays and holidays. The weather is also influential as the number of visitors decreases on rainy and snowy days. Comparing different seasons of the year, we found that influential factors varied from one season to the other. A key distinguishing finding of our results is that the weather conditions at the departure site and the weather forecast are also determining factors. These findings will help park managers understand the current situations and examine future management strategies to maintain and enhance visitor satisfaction, and improve information services.

  18. Evaluation of speech transmission in open public spaces affected by combined noises.

    Science.gov (United States)

    Lee, Pyoung Jik; Jeon, Jin Yong

    2011-07-01

    In the present study, the effects of interference from combined noises on speech transmission were investigated in a simulated open public space. Sound fields for dominant noises were predicted using a typical urban square model surrounded by buildings. Then road traffic noise and two types of construction noises, corresponding to stationary and impulsive noises, were selected as background noises. Listening tests were performed on a group of adults, and the quality of speech transmission was evaluated using listening difficulty as well as intelligibility scores. During the listening tests, two factors that affect speech transmission performance were considered: (1) temporal characteristics of construction noise (stationary or impulsive) and (2) the levels of the construction and road traffic noises. The results indicated that word intelligibility scores and listening difficulty ratings were affected by the temporal characteristics of construction noise due to fluctuations in the background noise level. It was also observed that listening difficulty is unable to describe the speech transmission in noisy open public spaces showing larger variation than did word intelligibility scores. © 2011 Acoustical Society of America

  19. Examining public open spaces by neighborhood-level walkability and deprivation.

    Science.gov (United States)

    Badland, Hannah M; Keam, Rosanna; Witten, Karen; Kearns, Robin

    2010-11-01

    Public open spaces (POS) are recognized as important to promote physical activity engagement. However, it is unclear how POS attributes, such as activities available, environmental quality, amenities present, and safety, are associated with neighborhood-level walkability and deprivation. Twelve neighborhoods were selected within 1 constituent city of Auckland, New Zealand based on higher (n = 6) or lower (n = 6) walkability characteristics. Neighborhoods were dichotomized as more (n = 7) or less (n = 5) socioeconomically deprived. POS (n = 69) were identified within these neighborhoods and audited using the New Zealand-Public Open Space Tool. Unpaired 1-way analysis of variance tests were applied to compare differences in attributes and overall score of POS by neighborhood walkability and deprivation. POS located in more walkable neighborhoods have significantly higher overall scores when compared with less walkable neighborhoods. Deprivation comparisons identified POS located in less deprived communities have better quality environments, but fewer activities and safety features present when compared with more deprived neighborhoods. A positive relationship existed between presence of POS attributes and neighborhood walkability, but the relationship between POS and neighborhood-level deprivation was less clear. Variation in neighborhood POS quality alone is unlikely to explain poorer health outcomes for residents in more deprived areas.

  20. Operation approaches on α-γ-I-open sets and α-γ-I-continuous functions in topological spaces

    Directory of Open Access Journals (Sweden)

    N. Kalaivani

    2014-07-01

    Full Text Available In this paper, the notion of α-γ-I-open sets in a topological space together with its corresponding interior and closure operators are introduced. Further, the concept of α-γ-I-continuous functions and α-γ-I-open functions are introduced and some of their basic properties are studied.

  1. Space Telescope Sensitivity and Controls for Exoplanet Imaging

    Science.gov (United States)

    Lyon, Richard G.; Clampin, Mark

    2012-01-01

    Herein we address design considerations and outline requirements for space telescopes with capabilities for high contrast imaging of exoplanets. The approach taken is to identify the span of potentially detectable Earth-sized terrestrial planets in the habitable zone of the nearest stars within 30 parsecs and estimate their inner working angles, flux ratios, SNR, sensitivities, wavefront error requirements and sensing and control times parametrically versus aperture size. We consider 1, 2, 4, 8 and 16-meter diameter telescope apertures. The achievable science, range of telescope architectures, and the coronagraphic approach are all active areas of research and are all subject to change in a rapidly evolving field. Thus, presented is a snapshot of our current understanding with the goal of limiting the choices to those that appear currently technically feasible. We describe the top-level metrics of inner working angle, contrast and photometric throughput and explore how they are related to the range of target stars. A critical point is that for each telescope architecture and coronagraphic choice the telescope stability requirements have differing impacts on the design for open versus closed-loop sensing and control.

  2. An Effective Approach Control Scheme for the Tethered Space Robot System

    Directory of Open Access Journals (Sweden)

    Zhongjie Meng

    2014-09-01

    Full Text Available The tethered space robot system (TSR, which is composed of a platform, a gripper and a space tether, has great potential in future space missions. Given the relative motion among the platform, tether, gripper and the target, an integrated approach model is derived. Then, a novel coordinated approach control scheme is presented, in which the tether tension, thrusters and the reaction wheel are all utilized. It contains the open-loop trajectory optimization, the feedback trajectory control and attitude control. The numerical simulation results show that the rendezvous between TSR and the target can be realized by the proposed coordinated control scheme, and the propellant consumption is efficiently reduced. Moreover, the control scheme performs well in the presence of the initial state’s perturbations, actuator characteristics and sensor errors.

  3. STRUCTURAL EVALUATION OF PSSDB WALL PANEL WITH SQUARE OPENING AND VARIED SCREW SPACING

    Directory of Open Access Journals (Sweden)

    SITI HAWA HAMZAH

    2009-03-01

    Full Text Available Profiled steel sheet dry boards or PSSDB system is an alternative composite construction system comprising of profiled steel sheet compositely connected to dry boards by self-tapping self-driving screws. PSSDB system was used widely as flooring system in the lightweight construction of buildings and office space in factories. Due to its superiority in the installation techniques, PSSDB system was expanded in the application as load bearing wall panel system in buildings. The PSSDB system is as an alternative construction technique on load bearing wall panel that offers cost savings synonymously with the rapid progress of science and technology which leads to the shift from traditional utilization of construction materials to newer construction techniques. A finite element analysis was carried out to determine the effect of screw spacing on the PSSDB wall panel. The spacing selected was between 100 mm to 500 mm, at an increment of 100 mm in each different model. The wall panel measured 3000 mm by 3000 mm with a 1200 mm square window opening, 78 mm thick and butt joints vertically positioned in the dry boards. This paper looks into the system as load bearing wall panels, analyzing it under axial compressive load using established Finite Element technique. The deformation profile of the PSSDB wall panel system showed a single curvature deformation profile, maximum lateral displacement at two-thirds wall panel height and critical sections at the upper corners of the square opening. The finite element analysis had provided good prediction of the structural behavior of the PSSDB wall panel system and it is concluded that the PW200 model possesses the optimum arrangement of the fixing screws used.

  4. Optimal control of large space structures via generalized inverse matrix

    Science.gov (United States)

    Nguyen, Charles C.; Fang, Xiaowen

    1987-01-01

    Independent Modal Space Control (IMSC) is a control scheme that decouples the space structure into n independent second-order subsystems according to n controlled modes and controls each mode independently. It is well-known that the IMSC eliminates control and observation spillover caused when the conventional coupled modal control scheme is employed. The independent control of each mode requires that the number of actuators be equal to the number of modelled modes, which is very high for a faithful modeling of large space structures. A control scheme is proposed that allows one to use a reduced number of actuators to control all modeled modes suboptimally. In particular, the method of generalized inverse matrices is employed to implement the actuators such that the eigenvalues of the closed-loop system are as closed as possible to those specified by the optimal IMSC. Computer simulation of the proposed control scheme on a simply supported beam is given.

  5. An Experimental Study on the Influence of Soundscapes on People’s Behaviour in an Open Public Space

    Directory of Open Access Journals (Sweden)

    Francesco Aletta

    2016-09-01

    Full Text Available Several studies have investigated how environmental sounds and music can modulate people’s behaviours, particularly in marketing research. However, there are relatively few examples of research about such relationships with a focus on the management of urban public spaces. The current study investigated an open public space used mainly as a pedestrian crossing to analyse the relationship between the audio stimuli and peoples’ behaviours. An experiment relying on covert behavioural observation was performed. During the experiment, three different music stimuli and a control condition (i.e., no music were reproduced in order to find out firstly whether music compared to no music could elicit an increase in the number of people stopping in the investigated area, and secondly whether music is associated with a longer duration of stay for those who stop. Results showed that the presence of music had no effect on the number of people stopping in the area, but it had a statistically significant effect on the duration of stay for those who stopped. The above findings support the idea that people felt more invited to stay in the area with music rather than with no music, and suggest that the acoustical manipulation of the existing sound environment could provide soundscape strategies capable of promoting social cohesion in public spaces.

  6. Management of an Adult with Spaced Dentition, Class III Malocclusion and Open-bite Tendency.

    Science.gov (United States)

    Kaya, Demet; Taner, Tulin Ugur

    2011-01-01

    The aim of this case report was to present the orthodontic treatment of an adult with spaced dentition, Class III malocclusion, and open-bite tendency. A 28.4-year-old adult woman was concerned about the unesthetic appearance of her spaced dentition localized at both upper and lower arches while smiling. She had a mild tongue thrust, hypertropic upper frenum, and mild speech difficulty while pronouncing "s". Her profile was straight with prominent lips. Molar relationship was Class III on both sides. Anterior teeth were in an end-to-end relationship. Lower dental midline was deviated to the left side. Cephalometric analysis revealed a skeletal Class III relationship with hyperdivergent facial pattern. The treatment plan included myotherapeutic exercises for the tongue thrust habit and a diagnostic set-up for closure of diastemas. A strict retention protocol was followed combined with gingivoplasty, fiberotomy, and frenectomy procedures. All spaces were closed successfully, adequate overbite and overjet relationships were obtained, and tongue thrust habit and speech difficulty while pronouncing "s" were eliminated. Clinical and cephalometric results indicated the maintenance of the treatment outcome at 6-months post-retention period.

  7. Open Innovation Drug Discovery (OIDD): a potential path to novel therapeutic chemical space.

    Science.gov (United States)

    Alvim-Gaston, Maria; Grese, Timothy; Mahoui, Abdelaziz; Palkowitz, Alan D; Pineiro-Nunez, Marta; Watson, Ian

    2014-01-01

    The continued development of computational and synthetic methods has enabled the enumeration or preparation of a nearly endless universe of chemical structures. Nevertheless, the ability of this chemical universe to deliver small molecules that can both modulate biological targets and have drug-like physicochemical properties continues to be a topic of interest to the pharmaceutical industry and academic researchers alike. The chemical space described by public, commercial, in-house and virtual compound collections has been interrogated by multiple approaches including biochemical, cellular and virtual screening, diversity analysis, and in-silico profiling. However, current drugs and known chemical probes derived from these efforts are contained within a remarkably small volume of the predicted chemical space. Access to more diverse classes of chemical scaffolds that maintain the properties relevant for drug discovery is certainly needed to meet the increasing demands for pharmaceutical innovation. The Lilly Open Innovation Drug Discovery platform (OIDD) was designed to tackle barriers to innovation through the identification of novel molecules active in relevant disease biology models. In this article we will discuss several computational approaches towards describing novel, biologically active, drug-like chemical space and illustrate how the OIDD program may facilitate access to previously untapped molecules that may aid in the search for innovative pharmaceuticals.

  8. Open Hypermedia as User Controlled Meta Data for the Web

    DEFF Research Database (Denmark)

    Grønbæk, Kaj; Sloth, Lennert; Bouvin, Niels Olof

    2000-01-01

    This paper introduces an approach to utilise open hypermedia structures such as links, annotations, collections and guided tours as meta data for Web resources. The paper introduces an XML based data format, called Open Hypermedia Interchange Format - OHIF, for such hypermedia structures. OHIF re...

  9. Acceleration of a Particle-in-Cell Code for Space Plasma Simulations with OpenACC

    Science.gov (United States)

    Peng, Ivy Bo; Markidis, Stefano; Vaivads, Andris; Vencels, Juris; Deca, Jan; Lapenta, Giovanni; Hart, Alistair; Laure, Erwin

    2015-04-01

    We simulate space plasmas with the Particle-in-cell (PIC) method that uses computational particles to mimic electrons and protons in solar wind and in Earth magnetosphere. The magnetic and electric fields are computed by solving the Maxwell's equations on a computational grid. In each PIC simulation step, there are four major phases: interpolation of fields to particles, updating the location and velocity of each particle, interpolation of particles to grids and solving the Maxwell's equations on the grid. We use the iPIC3D code, which was implemented in C++, using both MPI and OpenMP, for our case study. By November 2014, heterogeneous systems using hardware accelerators such as Graphics Processing Unit (GPUs) and the Many Integrated Core (MIC) coprocessors for high performance computing continue growth in the top 500 most powerful supercomputers world wide. Scientific applications for numerical simulations need to adapt to using accelerators to achieve portability and scalability in the coming exascale systems. In our work, we conduct a case study of using OpenACC to offload the computation intensive parts: particle mover and interpolation of particles to grids, in a massively parallel Particle-in-Cell simulation code, iPIC3D, to multi-GPU systems. We use MPI for inter-node communication for halo exchange and communicating particles. We identify the most promising parts suitable for GPUs accelerator by profiling using CrayPAT. We implemented manual deep copy to address the challenges of porting C++ classes to GPU. We document the necessary changes in the exiting algorithms to adapt for GPU computation. We present the challenges and findings as well as our methodology for porting a Particle-in-Cell code to multi-GPU systems using OpenACC. In this work, we will present the challenges, findings and our methodology of porting a Particle-in-Cell code for space applications as follows: We profile the iPIC3D code by Cray Performance Analysis Tool (CrayPAT) and identify

  10. Experimental implementation of the modified independent modal space control method

    Science.gov (United States)

    Baz, A.; Poh, S.

    1990-01-01

    An experimental realization of a modified independent modal space control (MIMSC) method to control the vibration of a flexible cantilevered beam is presented. In its operation the method relies on the use of one piezoelectric actuator to control several vibration modes through a time-sharing strategy. The effectiveness of the MIMSC method in damping out the beam vibration is demonstrated by comparing the results with those obtained by other modal control methods. Two methods are considered, the independent modal space control method and the pseudo-inverse method. The feasibility of the MIMSC method as a viable alternative for controlling large flexible structures with a very small number of actuators is emphasized.

  11. Sustainable Sites Initiative: US updated rating criteria for open spaces design

    Directory of Open Access Journals (Sweden)

    Renata Valente

    2014-10-01

    Full Text Available The paper presents the U.S. Sustainable Sites Initiative, by illustrating and commenting the recent updates of the rating criteria in addition to a number of certified projects, including some sites visited by the author in California. The system is compared with existing tools, as LEED 2009 for Neighborhood Development Rating System, albeit some differences also in scale of interventions. In the work, scientific literature and personal considerations are given about those aspects still not evaluated by the system and its potential wider applicability with regard to directions of research on the topic. The theme fits well in the mainstream of studies dedicated to the design of resilient open spaces, contributing to adaptation and mitigation of climate change.

  12. Statistics of scattered photons from a driven three-level emitter in 1D open space

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Dibyendu [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Div. and Center for Nonlinear Studies; Bondyopadhaya, Nilanjan [Visva-Bharati University, Santiniketan (India). Integrated Science Education and Research Centre

    2014-01-07

    We derive the statistics of scattered photons from a Λ- or ladder-type three-level emitter (3LE) embedded in a 1D open waveguide. The weak probe photons in the waveguide are coupled to one of the two allowed transitions of the 3LE, and the other transition is driven by a control beam. This system shows electromagnetically induced transparency (EIT) which is accompanied with the Autler-Townes splitting (ATS) at a strong driving by the control beam, and some of these effects have been observed recently. We show that the nature of second-order coherence of the transmitted probe photons near two-photon resonance changes from bunching to antibunching to constant as strength of the control beam is ramped up from zero to a higher value where the ATS appears.

  13. Investment in Open Innovation Service Providers: NASA's Innovative Strategy for Solving Space Exploration Challenges

    Science.gov (United States)

    Fogarty, Jennifer A.; Rando, Cynthia; Baumann, David; Richard, Elizabeth; Davis, Jeffrey

    2010-01-01

    In an effort to expand routes for open communication and create additional opportunities for public involvement with NASA, Open Innovation Service Provider (OISP) methodologies have been incorporated as a tool in NASA's problem solving strategy. NASA engaged the services of two OISP providers, InnoCentive and Yet2.com, to test this novel approach and its feasibility in solving NASA s space flight challenges. The OISPs were chosen based on multiple factors including: network size and knowledge area span, established process, methodology, experience base, and cost. InnoCentive and Yet2.com each met the desired criteria; however each company s approach to Open Innovation is distinctly different. InnoCentive focuses on posting individual challenges to an established web-based network of approximately 200,000 solvers; viable solutions are sought and granted a financial award if found. Based on a specific technological need, Yet2.com acts as a talent scout providing a broad external network of experts as potential collaborators to NASA. A relationship can be established with these contacts to develop technologies and/or maintained as an established network of future collaborators. The results from the first phase of the pilot study have shown great promise for long term efficacy of utilizing the OISP methodologies. Solution proposals have been received for the challenges posted on InnoCentive and are currently under review for final disposition. In addition, Yet2.com has identified new external partners for NASA and we are in the process of understanding and acting upon these new opportunities. Compared to NASA's traditional routes for external problem solving, the OISP methodologies offered NASA a substantial savings in terms of time and resources invested. In addition, these strategies will help NASA extend beyond its current borders to build an ever expanding network of experts and global solvers.

  14. Investment in Open Innovation Service Providers: NASA's Innovative Strategy for Solving Space Exploration Challenges

    Science.gov (United States)

    Fogarty, Jennifer A.; Rando, Cynthia; Baumann, David; Richard, Elizabeth; Davis, Jeffrey

    2010-01-01

    In an effort to expand routes for open communication and create additional opportunities for public involvement with NASA, Open Innovation Service Provider (OISP) methodologies have been incorporated as a tool in NASA's problem solving strategy. NASA engaged the services of two OISP providers, InnoCentive and Yet2.com, to test this novel approach and its feasibility in solving NASA s space flight challenges. The OISPs were chosen based on multiple factors including: network size and knowledge area span, established process, methodology, experience base, and cost. InnoCentive and Yet2.com each met the desired criteria; however each company s approach to Open Innovation is distinctly different. InnoCentive focuses on posting individual challenges to an established web-based network of approximately 200,000 solvers; viable solutions are sought and granted a financial award if found. Based on a specific technological need, Yet2.com acts as a talent scout providing a broad external network of experts as potential collaborators to NASA. A relationship can be established with these contacts to develop technologies and/or maintained as an established network of future collaborators. The results from the first phase of the pilot study have shown great promise for long term efficacy of utilizing the OISP methodologies. Solution proposals have been received for the challenges posted on InnoCentive and are currently under review for final disposition. In addition, Yet2.com has identified new external partners for NASA and we are in the process of understanding and acting upon these new opportunities. Compared to NASA's traditional routes for external problem solving, the OISP methodologies offered NASA a substantial savings in terms of time and resources invested. In addition, these strategies will help NASA extend beyond its current borders to build an ever expanding network of experts and global solvers.

  15. Design of a real-time open architecture controller for a reconfigurable machine tool

    CSIR Research Space (South Africa)

    Masekamela, I

    2008-11-01

    Full Text Available The paper presents the design and the development of a real-time, open architecture controller that is used for control of reconfigurable manufacturing tools (RMTs) in reconfigurable manufacturing systems (RMS). The controller that is presented can...

  16. Predictive Control Based upon State Space Models

    Directory of Open Access Journals (Sweden)

    Jens G. Balchen

    1989-04-01

    Full Text Available Repetitive online computation of the control vector by solving the optimal control problem of a non-linear multivariable process with arbitrary performance indices is investigated. Two different methods are considered in the search for an optimal, parameterized control vector: Pontryagin's Maximum Principle and optimization by using the performance index and its gradient directly. Unfortunately, solving this optimization problem has turned out to be a rather time-consuming task which has resulted in a time delay that cannot be accepted when the actual process is exposed to rapidly-varying disturbances. However, an instantaneous feedback strategy operating in parallel with the original control aogorithm was found to be able to cope with this problem.

  17. Controllability of Impulsive Neutral Functional Differential Inclusions in Banach Spaces

    Directory of Open Access Journals (Sweden)

    X. J. Wan

    2013-01-01

    Full Text Available We investigate the controllability of impulsive neutral functional differential inclusions in Banach spaces. Our main aim is to find an effective method to solve the controllability problem of impulsive neutral functional differential inclusions with multivalued jump sizes in Banach spaces. Based on a fixed point theorem with regard to condensing map, sufficient conditions for the controllability of the impulsive neutral functional differential inclusions in Banach spaces are derived. Moreover, a remark is given to explain less conservative criteria for special cases, and work is improved in the previous literature.

  18. Sensitivity study on critical flow models of SPACE for inadvertent opening of containment spray valve in Shin Kori unit 1

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seyun; Kim, Minhee [KHNP Central Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    SPACE (Safety and Performance Analysis Code for Nuclear Power Plants) has been developed by KHNP with the cooperation with KEPCO E and C and KAERI. SPACE code is expected to be applied to the safety analysis for LOCA (Loss of Coolant Accident) and Non-LOCA scenarios. SPACE code solves two-fluid, three-field governing equations and programmed with C++ computer language using object-oriented concepts. To evaluate the analysis capability for the transient phenomena in the actual nuclear power plant, an inadvertent opening of spray valve in startup test phase of Shin Kori unit 1 was simulated with SPACE. To assess the critical flow models of SPACE, the calculation with several critical flow models were carried out. The simulations of an inadvertent opening of spray valve of Shin Kori unit 1 with several critical flow models were carried out. The calculated transient behaviors of major reactor parameters with four critical flow models generally show good agreement with the measured.

  19. The Relationship of Children Connectivity and Physical Activities with Satisfaction of Open Spaces in High Rise Apartments in Tehran

    Directory of Open Access Journals (Sweden)

    Ali Sharghi

    2014-07-01

    Full Text Available Increase of urbanization has pressure on the urban children's lives and physical activities. While in designing of residential apartments’ open spaces, there is little attention to the children. The children, who live in the high-rise apartments found to have less physical activities. However, supposedly, children need to engage in the physical activity in the outdoor areas as WHO recommend that children take part in at least one hour of moderate physical activity in every day. This paper firstly, reviews different researches in this area. Then, it attempts to find children’s satisfaction regarding connectivity to open spaces as a dependent variable and their preferred activities, perceived safety, and familiarity about connectivity to open spaces as independent variables. The method of study is a semi-interview survey with 80 children between 6 and 12 years old (primary school ages in two cases in Tehran. The result of this research shows that children satisfaction from open space has an effect on their outdoor activities. Therefore, the designers should be considering children physical activities needs in open spaces.

  20. Applying Space Technology to Enhance Control of an Artificial Arm

    Science.gov (United States)

    Atkins, Diane; Donovan, William H.; Novy, Mara; Abramczyk, Robert

    1997-01-01

    At the present time, myoelectric prostheses perform only one function of the hand: open and close with the thumb, index and middle finger coming together to grasp various shaped objects. To better understand the limitations of the current single-function prostheses and the needs of the individuals who use them, The Institute for Rehabilitation and Research (TIRR), sponsored by the National Institutes of Health (August 1992 - November 1994), surveyed approximately 2500 individuals with upper limb loss. When asked to identify specific features of their current electric prosthesis that needed improvement, the survey respondents overwhelmingly identified the lack of wrist and finger movement as well as poor control capability. Simply building a mechanism with individual finger and wrist motion is not enough. Individuals with upper limb loss tend to reject prostheses that require continuous visual monitoring and concentration to control. Robotics researchers at NASA's Johnson Space Center (JSC) and Rice University have made substantial progress in myoelectric teleoperation. A myoelectric teleoperation system translates signals generated by an able-bodied robot operator's muscles during hand motions into commands that drive a robot's hand through identical motions. Farry's early work in myoelectric teleoperation used variations over time in the myoelectric spectrum as inputs to neural networks to discriminate grasp types and thumb motions. The resulting schemes yielded up to 93% correct classification on thumb motions. More recently, Fernandez achieved 100% correct non-realtime classification of thumb abduction, extension, and flexion on the same myoelectric data. Fernandez used genetic programming to develop functions that discriminate between thumb motions using myoelectric signal parameters. Genetic programming (GP) is an evolutionary programming method where the computer can modify the discriminating functions' form to improve its performance, not just adjust

  1. Modeling Open Software Architectures of Robot Controllers: A Brief Survey of Modeling Methods and Developing Methods

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Openness is one of the features of modern robot controllers. Although many modeling technologies have been discussed to model and develop open robot controllers, the focus is always on modeling methodologies. Meanwhile, the relations between the former and the latter are usually ignored. According to the general software architecture of open robot controllers, this paper discusses modeling and developing methods. And the relationships between the typical ones are also analyzed.

  2. Remote control circuit breaker evaluation testing. [for space shuttles

    Science.gov (United States)

    Bemko, L. M.

    1974-01-01

    Engineering evaluation tests were performed on several models/types of remote control circuit breakers marketed in an attempt to gain some insight into their potential suitability for use on the space shuttle vehicle. Tests included the measurement of several electrical and operational performance parameters under laboratory ambient, space simulation, acceleration and vibration environmental conditions.

  3. Remote control circuit breaker evaluation testing. [for space shuttles

    Science.gov (United States)

    Bemko, L. M.

    1974-01-01

    Engineering evaluation tests were performed on several models/types of remote control circuit breakers marketed in an attempt to gain some insight into their potential suitability for use on the space shuttle vehicle. Tests included the measurement of several electrical and operational performance parameters under laboratory ambient, space simulation, acceleration and vibration environmental conditions.

  4. Application of innovative policies for controlling radionuclide releases: The {open_quotes}open-market trading rule{close_quotes}

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, D.W. [Dade Moeller & Associates, Inc., New Bern, NC (United States)

    1997-08-01

    In the past, most efforts for reducing airborne radio nuclide releases and controlling radioactive wastes have been directed to the development of new and improved technologies. Little attention has been paid to the possible application to these problems of new, innovative policies. Yet, experience in other fields shows that such applications could be beneficial. A prime example is the {open_quotes}open-market trading rule,{close_quotes} now being widely used in the U.S. for the control of a range of environmental problems. Through this rule, nuclear facility operators would be permitted to control airborne emissions in a more cost-effective manner, and those responsible for decommissioning and decontaminating nuclear facilities no longer in operation could do so at far lower costs while generating significantly smaller volumes of radioactive wastes. Application of such a policy would also significantly reduce the demands on existing, and the need for research to develop new, improved, control technologies. 16 refs.

  5. Approximate controllability of semilinear neutral systems in Hilbert spaces

    Directory of Open Access Journals (Sweden)

    N. I. Mahmudov

    2003-01-01

    Full Text Available The approximate controllability of semilinear neutral systems in Hilbert spaces is studied using the Schauder fixed point theorem. It is shown that the approximate controllability of the semilinear system under some conditions is implied by the approximate controllability of its linear part.

  6. Null controllability and the algebraic Riccati equation in Banach Spaces

    NARCIS (Netherlands)

    Van Neerven, J.M.A.M.

    2005-01-01

    By a recent result of Priola and Zabczyk, a null controllable linear system [y'(t) = Ay(t) + Bu(t)] in a Hilbert space E is null controllable with vanishing energy if and only if it is null controllable and the only positive self-adjoint solution of the associated algebraic Riccati equation [XA + A*

  7. Coordinated coupling control of tethered space robot using releasing characteristics of space tether

    Science.gov (United States)

    Huang, Panfeng; Zhang, Fan; Xu, Xiudong; Meng, Zhongjie; Liu, Zhengxiong; Hu, Yongxin

    2016-04-01

    Tethered space robot (TSR) is a new concept of space robot, which is released from the platform satellite, and retrieved via connected tether after space debris capture. In this paper, we propose a new coordinate control scheme for optimal trajectory and attitude tracking, and use releasing motor torque to instead the tension force, since it is difficult to track in practical. Firstly, the 6-DOF dynamics model of TSR is derived, in which the dynamics of tether releasing system is taken into account. Then, we propose and design the coordinated coupled controller, which is composed of a 6-DOF sliding mode controller and a PD controller tether's releasing. Thrust is treated as control input of the 6-DOF sliding mode controller to control the in-plane and out-of-plane angle of the tether and attitude angles of the TSR. The torque of releasing motor is used as input of PD controller, which controls the length rate of space tether. After the verification of the control scheme, finally, the simulation experiment is presented in order to validate the effectiveness of this control method. The results show that TSR can track the optimal approaching trajectory accurately. Simultaneously, the attitude angles can be changed to the desired attitude angles in control period, and the terminal accuracy is ±0.3°.

  8. Universal Brushless-DC Motor Controller for Space Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The goal of this SBIR is to adapt an initial prototype ultra-miniature high-performance brushless-DC-motor controller, code named 'Puck', for use by NASA across a...

  9. Boundary Controllability of Integrodifferential Systems in Banach Spaces

    Indian Academy of Sciences (India)

    K Balachandran; E R Anandhi

    2001-02-01

    Sufficient conditions for boundary controllability of integrodifferential systems in Banach spaces are established. The results are obtained by using the strongly continuous semigroup theory and the Banach contraction principle. Examples are provided to illustrate the theory.

  10. Research into command, control, and communications in space construction

    Science.gov (United States)

    Davis, Randal

    1990-01-01

    Coordinating and controlling large numbers of autonomous or semi-autonomous robot elements in a space construction activity will present problems that are very different from most command and control problems encountered in the space business. As part of our research into the feasibility of robot constructors in space, the CSC Operations Group is examining a variety of command, control, and communications (C3) issues. Two major questions being asked are: can we apply C3 techniques and technologies already developed for use in space; and are there suitable terrestrial solutions for extraterrestrial C3 problems? An overview of the control architectures, command strategies, and communications technologies that we are examining is provided and plans for simulations and demonstrations of our concepts are described.

  11. OPEN

    DEFF Research Database (Denmark)

    Nickelsen, Anders; Paterno, Fabio; Grasselli, Agnese;

    2010-01-01

    One important aspect of ubiquitous environments is to provide users with the possibility to freely move about and continue to interact with the available applications through a variety of interactive devices such as cell phones, PDAs, desktop computers, intelligent watches or digital television...... and be controlled by the platform to enrich the user experience with the application. We describe the challenges following the centralisation of a migration platform that can support different types of applications, both games and business applications, implemented with either web-technologies or as component...

  12. Space Transportation Systems Life Cycle Cost Assessment and Control

    Science.gov (United States)

    Robinson, John W.; Rhodes, Russell E.; Zapata, Edgar; Levack, Daniel J. H.; Donahue, Benjaamin B.; Knuth, William

    2008-01-01

    Civil and military applications of space transportation have been pursued for just over 50 years and there has been, and still is, a need for safe, dependable, affordable, and sustainable space transportation systems. Fully expendable and partially reusable space transportation systems have been developed and put in operation that have not adequately achieved this need. Access to space is technically achievable, but presently very expensive and will remain so until there is a breakthrough in the way we do business. Since 1991 the national Space Propulsion Synergy Team (SPST) has reviewed and assessed the lessons learned from the major U.S. space programs of the past decades focusing on what has been learned from the assessment and control of Life Cycle Cost (LCC) from these systems. This paper presents the results of a selected number of studies and analyses that have been conducted by the SPST addressing the need, as well as the solutions, for improvement in LCC. The major emphasis of the SPST processes is on developing the space transportation system requirements first (up front). These requirements must include both the usual system flight performance requirements and also the system functional requirements, including the infrastructure on Earth's surface, in-space and on the Moon and Mars surfaces to determine LCC. This paper describes the development of specific innovative engineering and management approaches and processes. This includes a focus on flight hardware maturity for reliability, ground operations approaches, and business processes between contractor and government organizations. A major change in program/project cost control is being proposed by the SPST to achieve a sustainable space transportation system LCC - controlling cost as a program metric in addition to the existing practice of controlling performance and weight. Without a firm requirement and methodically structured cost control, it is unlikely that an affordable and sustainable space

  13. Identification and control of structures in space

    Science.gov (United States)

    Meirovitch, L.; Quinn, R. D.; Norris, M. A.

    1984-01-01

    The derivation of the equations of motion for the Spacecraft Control Laboratory Experiment (SCOLE) is reported and the equations of motion of a similar structure orbiting the earth are also derived. The structure is assumed to undergo large rigid-body maneuvers and small elastic deformations. A perturbation approach is proposed whereby the quantities defining the rigid-body maneuver are assumed to be relatively large, with the elastic deformations and deviations from the rigid-body maneuver being relatively small. The perturbation equations have the form of linear equations with time-dependent coefficients. An active control technique can then be formulated to permit maneuvering of the spacecraft and simultaneously suppressing the elastic vibration.

  14. Toward an open-access global database for mapping, control, and surveillance of neglected tropical diseases.

    Directory of Open Access Journals (Sweden)

    Eveline Hürlimann

    2011-12-01

    Full Text Available BACKGROUND: After many years of general neglect, interest has grown and efforts came under way for the mapping, control, surveillance, and eventual elimination of neglected tropical diseases (NTDs. Disease risk estimates are a key feature to target control interventions, and serve as a benchmark for monitoring and evaluation. What is currently missing is a georeferenced global database for NTDs providing open-access to the available survey data that is constantly updated and can be utilized by researchers and disease control managers to support other relevant stakeholders. We describe the steps taken toward the development of such a database that can be employed for spatial disease risk modeling and control of NTDs. METHODOLOGY: With an emphasis on schistosomiasis in Africa, we systematically searched the literature (peer-reviewed journals and 'grey literature', contacted Ministries of Health and research institutions in schistosomiasis-endemic countries for location-specific prevalence data and survey details (e.g., study population, year of survey and diagnostic techniques. The data were extracted, georeferenced, and stored in a MySQL database with a web interface allowing free database access and data management. PRINCIPAL FINDINGS: At the beginning of 2011, our database contained more than 12,000 georeferenced schistosomiasis survey locations from 35 African countries available under http://www.gntd.org. Currently, the database is expanded to a global repository, including a host of other NTDs, e.g. soil-transmitted helminthiasis and leishmaniasis. CONCLUSIONS: An open-access, spatially explicit NTD database offers unique opportunities for disease risk modeling, targeting control interventions, disease monitoring, and surveillance. Moreover, it allows for detailed geostatistical analyses of disease distribution in space and time. With an initial focus on schistosomiasis in Africa, we demonstrate the proof-of-concept that the establishment

  15. Adaptive Correlation Space Adjusted Open-Loop Tracking Approach for Vehicle Positioning with Global Navigation Satellite System in Urban Areas.

    Science.gov (United States)

    Ruan, Hang; Li, Jian; Zhang, Lei; Long, Teng

    2015-08-28

    For vehicle positioning with Global Navigation Satellite System (GNSS) in urban areas, open-loop tracking shows better performance because of its high sensitivity and superior robustness against multipath. However, no previous study has focused on the effects of the code search grid size on the code phase measurement accuracy of open-loop tracking. Traditional open-loop tracking methods are performed by the batch correlators with fixed correlation space. The code search grid size, which is the correlation space, is a constant empirical value and the code phase measuring accuracy will be largely degraded due to the improper grid size, especially when the signal carrier-to-noise density ratio (C/N₀) varies. In this study, the Adaptive Correlation Space Adjusted Open-Loop Tracking Approach (ACSA-OLTA) is proposed to improve the code phase measurement dependent pseudo range accuracy. In ACSA-OLTA, the correlation space is adjusted according to the signal C/N₀. The novel Equivalent Weighted Pseudo Range Error (EWPRE) is raised to obtain the optimal code search grid sizes for different C/N₀. The code phase measuring errors of different measurement calculation methods are analyzed for the first time. The measurement calculation strategy of ACSA-OLTA is derived from the analysis to further improve the accuracy but reduce the correlator consumption. Performance simulation and real tests confirm that the pseudo range and positioning accuracy of ASCA-OLTA are better than the traditional open-loop tracking methods in the usual scenarios of urban area.

  16. Experimental implementation of adaptive control for flexible space structures

    Science.gov (United States)

    Mcgraw, Gary A.

    1988-01-01

    On-going research at The Aerospace Corporation studying the feasibility of applying adaptive control methodologies to the control of flexible space structures is described. A laboratory testbed was established to test system identification and control approaches. The laboratory set-up and controller design approach are discussed. The ARX least squares parameter estimation technique is analyzed in terms of frequency domain transfer function bias error. This analysis approach enables the determination of the effects of sampling rate, sensor type, and data prefiltering on the estimation performance. The ability to identify space structure dynamics over a range of frequencies is shown to be heavily dependent on these factors.

  17. Space station contamination control study: Internal combustion, phase 1

    Science.gov (United States)

    Ruggeri, Robert T.

    1987-01-01

    Contamination inside Space Station modules was studied to determine the best methods of controlling contamination. The work was conducted in five tasks that identified existing contamination control requirements, analyzed contamination levels, developed outgassing specification for materials, wrote a contamination control plan, and evaluated current materials of offgassing tests used by NASA. It is concluded that current contamination control methods can be made to function on the Space Station for up to 1000 days, but that current methods are deficient for periods longer than about 1000 days.

  18. Implementation of the Forest Service Open Space Conservation Strategy in Washington State: Exploring the Role of the National Forest System

    Science.gov (United States)

    Richard J. Pringle; Lee K. Cerveny; Gordon A. Bradley

    2015-01-01

    The loss of open space was declared one of the “four threats to the health of our nation’s forests” by former USDA Forest Service Chief Dale Bosworth in 2004. Since then, the agencywide Open Space Conservation Strategy (OSCS) was released and the “four threats” were incorporated into the agency’s National Strategic Plan. These actions indicate that the OSCS is in the...

  19. A digital open-loop Doppler processing prototype for deep-space navigation

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A prototype based on digital radio technology with associated open-loop Doppler signal processing techniques has been developed to measure a spacecraft’s line-of-sight velocity. The prototype was tested in China’s Chang’E-1 lunar mission relying on S-band telemetry signals transmitted by the sat-ellite,with results showing that the residuals had a RMS value of ~3 mm/s (1σ ) using 1-sec integration,which is consistent with the Chinese conventional USB (Unified S-Band) tracking system. Such preci-sion is mainly limited by the short-term stability of the atomic (e.g. rubidium) clock at the uplink ground station. It can also be improved with proper calibration to remove some effects of the transmission media (such as solar plasma,troposphere and ionosphere),and a longer integration time (e.g. down to 0.56 mm/s at 34 seconds) allowed by the spacecraft dynamics. The tracking accuracy can also be in-creased with differential methods that may effectively remove most of the long-term drifts and some of the short-term uncertainties of the uplink atomic clock,thereby further reducing the residuals to the 1 mm/s level. Our experimental tracking data have been used in orbit determination for Chang’E-1,while other applications (such as the upcoming YH-1 Mars orbiter) based on open-loop Doppler tracking will be initiated in the future. Successful application of the prototype to the Chang’E-1 mission in 2008 is believed to have great significance for China’s future deep space exploration.

  20. DETECTABILITY OF FREE FLOATING PLANETS IN OPEN CLUSTERS WITH THE JAMES WEBB SPACE TELESCOPE

    Energy Technology Data Exchange (ETDEWEB)

    Pacucci, Fabio; Ferrara, Andrea [Scuola Normale Superiore, Piazza dei Cavalieri 7, I-56126 Pisa (Italy); D' Onghia, Elena [University of Wisconsin, 475 Charter St., Madison, WI 53706 (United States)

    2013-12-01

    Recent observations have shown the presence of extra-solar planets in Galactic open stellar clusters, such as in Praesepe (M44). These systems provide a favorable environment for planetary formation due to the high heavy-element content exhibited by the majority of their population. The large stellar density, and corresponding high close-encounter event rate, may induce strong perturbations of planetary orbits with large semimajor axes. Here we present a set of N-body simulations implementing a novel scheme to treat the tidal effects of external stellar perturbers on planetary orbit eccentricity and inclination. By simulating five nearby open clusters, we determine the rate of occurrence of bodies extracted from their parent stellar system by quasi-impulsive tidal interactions. We find that the specific free-floating planet production rate N-dot {sub o} (total number of free-floating planets per unit of time, normalized by the total number of stars), is proportional to the stellar density ρ{sub *} of the cluster: N-dot {sub o}=αρ{sub ⋆}, with α = (23 ± 5) × 10{sup –6} pc{sup 3} Myr{sup –1}. For the Pleiades (M45), we predict that ∼26% of stars should have lost their planets. This raises the exciting possibility of directly observing these wandering planets with the James Webb Space Telescope in the near-infrared band. Assuming a surface temperature for the planet of ∼500 K, a free-floating planet of Jupiter size inside the Pleiades would have a specific flux of F {sub ν} (4.4 μm) ≈4 × 10{sup 2} nJy, which would lead to a very clear detection (S/N ∼ 100) in only one hour of integration.

  1. A digital open-loop Doppler processing prototype for deep-space navigation

    Institute of Scientific and Technical Information of China (English)

    JIAN NianChuan; QIU Shi; FUNG Lai-Wo; ZHANG Hua; WANG Zhen; GOU Wei; SHANG Kun; ZHANG SuJun; WANG MingYuan; SHI Xian; PING JingSong; YAN JianGuo; TANG GeShi; LIU JunZe

    2009-01-01

    A prototype based on digital radio technology with associated open-loop Doppler signal processing techniques has been developed to measure a spacecraft's line-of-sight velocity. The prototype was tested in China's Chang'E-1 lunar mission relying on S-band telemetry signals transmitted by the satellite, with results showing that the residuals had a RMS value of ~3 mm/s (1 σ ) using 1-sec integration, which is consistent with the Chinese conventional USB (Unified S-Band) tracking system. Such precision is mainly limited by the short-term stability of the atomic (e.g. Rubidium) clock at the uplink ground station. It can also be improved with proper calibration to remove some effects of the transmission media (such as solar plasma, troposphere and ionosphere), and a longer integration time (e.g. Down to 0.56 mm/s at 34 seconds) allowed by the spacecraft dynamics. The tracking accuracy can also be increased with differential methods that may effectively remove most of the long-term drifts and some of the short-term uncertainties of the uplink atomic clock, thereby further reducing the residuals to the 1 mm/s level. Our experimental tracking data have been used in orbit determination for Chang'E-1, while other applications (such as the upcoming YH-1 Mars orbiter) based on open-loop Doppler tracking will be initiated in the future. Successful application of the prototype to the Chang'E-1 mission in 2008 is believed to have great significance for China's future deep space exploration.

  2. Evaluation of SPACE code for simulation of inadvertent opening of spray valve in Shin Kori unit 1

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seyun; Youn, Bumsoo [KHNP Central Research Institute, Daejeon (Korea, Republic of)

    2013-05-15

    SPACE code is expected to be applied to the safety analysis for LOCA (Loss of Coolant Accident) and Non-LOCA scenarios. SPACE code solves two-fluid, three-field governing equations and programmed with C++ computer language using object-oriented concepts. To evaluate the analysis capability for the transient phenomena in the actual nuclear power plant, an inadvertent opening of spray valve in startup test phase of Shin Kori unit 1 was simulated with SPACE code. To evaluate the analysis capability for the transient phenomena in the actual nuclear power plant, an inadvertent opening of spray valve in startup test phase of Shin Kori unit 1 was simulated with SPACE code.

  3. Neuromorphic Continuous-Time State Space Pole Placement Adaptive Control

    Institute of Scientific and Technical Information of China (English)

    卢钊; 孙明伟

    2003-01-01

    A neuromorphic continuous-time state space pole assignment adaptive controller is proposed, which is particularly appropriate for controlling a large-scale time-variant state-space model due to the parallely distributed nature of neurocomputing. In our approach, Hopfield neural network is exploited to identify the parameters of a continuous-time state-space model, and a dedicated recurrent neural network is designed to compute pole placement feedback control law in real time. Thus the identification and the control computation are incorporated in the closed-loop, adaptive, real-time control system. The merit of this approach is that the neural networks converge to their solutions very quickly and simultaneously.

  4. Dancing droplets: Chemical space, substrates, and control

    Science.gov (United States)

    Cira, Nate; Benusiglio, Adrien; Prakash, Manu

    2015-11-01

    Previously we showed that droplets of propylene glycol and water display remarkable properties when placed on clean glass due to an interplay between surface tension and evaporation. (Cira, Benusiglio, Prakash: Nature, 2015). We showed that these mechanisms apply to a range of two-component mixtures of miscible liquids where one component has both higher surface tension and higher vapor pressure on a variety of high energy surfaces. We now show how this rule can be cheated using a simple trick. We go on to demonstrate applications for cleaning, and show how this system works on substrates prepared only with sunlight. We finish by demonstrating active control of droplets, allowing access to a host of new possibilities.

  5. Robust coordinated control of a dual-arm space robot

    Science.gov (United States)

    Shi, Lingling; Kayastha, Sharmila; Katupitiya, Jay

    2017-09-01

    Dual-arm space robots are more capable of implementing complex space tasks compared with single arm space robots. However, the dynamic coupling between the arms and the base will have a serious impact on the spacecraft attitude and the hand motion of each arm. Instead of considering one arm as the mission arm and the other as the balance arm, in this work two arms of the space robot perform as mission arms aimed at accomplishing secure capture of a floating target. The paper investigates coordinated control of the base's attitude and the arms' motion in the task space in the presence of system uncertainties. Two types of controllers, i.e. a Sliding Mode Controller (SMC) and a nonlinear Model Predictive Controller (MPC) are verified and compared with a conventional Computed-Torque Controller (CTC) through numerical simulations in terms of control accuracy and system robustness. Both controllers eliminate the need to linearly parameterize the dynamic equations. The MPC has been shown to achieve performance with higher accuracy than CTC and SMC in the absence of system uncertainties under the condition that they consume comparable energy. When the system uncertainties are included, SMC and CTC present advantageous robustness than MPC. Specifically, in a case where system inertia increases, SMC delivers higher accuracy than CTC and costs the least amount of energy.

  6. Procedures adopted by orthodontists for space closure and anchorage control

    Directory of Open Access Journals (Sweden)

    André da Costa Monini

    2013-12-01

    Full Text Available OBJECTIVE: The aim of this study was to identify the procedures adopted by Brazilian orthodontists in the following situations: extraction space closure, anchorage control in case of necessary anchorage for group A and frequency of skeletal anchorage use, especially in the upper jaw. METHOD: A questionnaire was sent to the e-mail address of all dentists registered in the Brazilian Federal Council of Dentistry. RESULTS: The results showed that most Brazilian orthodontists usually perform extraction space closure by means of sliding mechanics. The use of palatal bar, inclusion of second molars in the archwire and space closure performed in two phases are the most used techniques for anchorage control in the upper jaw. The skeletal anchorage is referenced by 36.5% of specialists as a routine practice for the upper jaw anchorage. CONCLUSIONS: There is a wide variety of procedures adopted by Brazilian orthodontists for orthodontic space closure and anchorage control.

  7. A geometric approach to quantum control in projective hilbert spaces

    Science.gov (United States)

    Pastorello, Davide

    2017-02-01

    A quantum theory in a finite-dimensional Hilbert space can be formulated as a proper geometric Hamiltonian theory as explained in [2, 3, 7, 9]. From this point of view a quantum system can be described within a classical-like framework where quantum dynamics is represented by a Hamiltonian flow in the phase space given by a projective Hilbert space. This paper is devoted to investigating how the notion of an accessibility algebra from classical control theory can be applied within the geometric Hamiltonian formulation of quantum mechanics to study controllability of a quantum system. A new characterization of quantum controllability in terms of Killing vector fields w.r.t. the Fubini-Study metric on projective space is also discussed.

  8. Automatic Design of a Maglev Controller in State Space

    Science.gov (United States)

    1991-12-01

    conventional trains with steel wheels on steel rails. Several experimen- tal maglev systems in Germany and Japan have demonstrated that this mode of...Design of a Maglev Controller in State Space Feng Zhao Richard Thornton Abstract We describe the automatic synthesis of a global nonlinear controller for...the global switching points of the controller is presented. The synthesized control system can stabilize the maglev vehicle with large initial displace

  9. Generalized Ψ;ρ-closed sets and generalized &Psiρ-open sets in double fuzzy topological spaces

    Science.gov (United States)

    Mohammed, Fatimah. M.; Noorani, M. S. M.; Ghareeb, A.

    2014-06-01

    The aim of this paper is to use the notion of Ψ-operations in double fuzzy topological spaces to study the concept of (r,s)-fuzzy generalized Ψρ-closed sets and (r,s)-fuzzy generalized Ψρ-open sets, some characterizations and properties of these concepts are given. Moreover, we discussed the relationship between these sets in double fuzzy topological spaces.

  10. Improving active space telescope wavefront control using predictive thermal modeling

    Science.gov (United States)

    Gersh-Range, Jessica; Perrin, Marshall D.

    2015-01-01

    Active control algorithms for space telescopes are less mature than those for large ground telescopes due to differences in the wavefront control problems. Active wavefront control for space telescopes at L2, such as the James Webb Space Telescope (JWST), requires weighing control costs against the benefits of correcting wavefront perturbations that are a predictable byproduct of the observing schedule, which is known and determined in advance. To improve the control algorithms for these telescopes, we have developed a model that calculates the temperature and wavefront evolution during a hypothetical mission, assuming the dominant wavefront perturbations are due to changes in the spacecraft attitude with respect to the sun. Using this model, we show that the wavefront can be controlled passively by introducing scheduling constraints that limit the allowable attitudes for an observation based on the observation duration and the mean telescope temperature. We also describe the implementation of a predictive controller designed to prevent the wavefront error (WFE) from exceeding a desired threshold. This controller outperforms simpler algorithms even with substantial model error, achieving a lower WFE without requiring significantly more corrections. Consequently, predictive wavefront control based on known spacecraft attitude plans is a promising approach for JWST and other future active space observatories.

  11. [Open loop gain of the CO2-ventilation feedback control system in chronic obstructive pulmonary disease].

    Science.gov (United States)

    Kimura, H; Kunitomo, F; Okita, S; Tojima, H; Tatsumi, K; Kuriyama, T; Hashizume, I; Honda, Y

    1989-07-01

    To evaluate the stability of the CO2-ventilation feedback system, we measured its open loop gain (G) in 12 patients with chronic obstructive pulmonary disease (COPD) and 15 control subjects. Then, we compared G to the conventional slope of the CO2-ventilation response line (S) and that of the metabolic hyperbola (SL). G was determined as the ratio of S to SL by applying external dead space of 250 and 500 ml. G, S and 1/SL in the control and the COPD were +17.1 +/- 7.2 (Mean +/- SD), 1.70 +/- 0.75 L.min-1.Torr-1 and -10.4 +/- 2.0 L-1.min.Torr, and -7.2 +/- 3.3, 0.48 +/- 0.27 L.min-1.Torr-1 and -16.1 +/- 6.4 L-1.min.Torr, respectively. G was significantly correlated with S in both groups, but that was not the case in 1/SL. The magnitude of G and S in COPD was about 42% and 28% of the control, indicating that G was maintained more stable than S. These data suggest that the decreased G in the COPD resulted from insufficient compensation of ventilatory drive, whereas 1/SL increased higher than the control. We conclude that G can be used to indicate the stability of the CO2-ventilation feedback system better than S.

  12. Energy efficient window opening for air quality control in classrooms

    DEFF Research Database (Denmark)

    Faria Da Silva, Nuno Alexandre

    2012-01-01

    on air quality when no CO2 feedback is installed, as less windows are opened then suggesting temperature as the main factor causing window opening. Children reported that they liked to use the CO2 feedback, with their perceptions and symptoms somewhat improved when feedback was installed but the results...... did not reach statistical significance. To improve indoor air quality in schools, CO2 feedback was shown to be an effective tool in naturally ventilated classrooms.......The aim of the present work was to study how to maximize indoor environmental quality and energy performance in classrooms, when having different ventilation alternatives combined with a visual CO2 feedback. In this effort, in heating and cooling seasons, field experiments were carried out in pairs...

  13. Dynamical control of quantum state transfer within hybrid open systems

    CERN Document Server

    Escher, B M; Clausen, J; Kurizki, G; Davidovich, L

    2010-01-01

    We analyze quantum state-transfer optimization within hybrid open systems, from a "noisy" (write-in) qubit to its "quiet" counterpart (storage qubit). Intriguing interplay is revealed between our ability to avoid bath-induced errors that profoundly depend on the bath-memory time and the limitations imposed by leakage out of the operational subspace. Counterintuitively, under no circumstances is the fastest transfer optimal (for a given transfer energy).

  14. Intelligent (Autonomous) Power Controller Development for Human Deep Space Exploration

    Science.gov (United States)

    Soeder, James; Raitano, Paul; McNelis, Anne

    2016-01-01

    As NASAs Evolvable Mars Campaign and other exploration initiatives continue to mature they have identified the need for more autonomous operations of the power system. For current human space operations such as the International Space Station, the paradigm is to perform the planning, operation and fault diagnosis from the ground. However, the dual problems of communication lag as well as limited communication bandwidth beyond GEO synchronous orbit, underscore the need to change the operation methodology for human operation in deep space. To address this need, for the past several years the Glenn Research Center has had an effort to develop an autonomous power controller for human deep space vehicles. This presentation discusses the present roadmap for deep space exploration along with a description of conceptual power system architecture for exploration modules. It then contrasts the present ground centric control and management architecture with limited autonomy on-board the spacecraft with an advanced autonomous power control system that features ground based monitoring with a spacecraft mission manager with autonomous control of all core systems, including power. It then presents a functional breakdown of the autonomous power control system and examines its operation in both normal and fault modes. Finally, it discusses progress made in the development of a real-time power system model and how it is being used to evaluate the performance of the controller and well as using it for verification of the overall operation.

  15. Real Space Multigrid (RMG) Open Source Software Suite for Multi-Petaflops Electronic Structure Calculations

    Science.gov (United States)

    Briggs, Emil; Hodak, Miroslav; Lu, Wenchang; Bernholc, Jerry; Li, Yan

    RMG is a cross platform open source package for ab initio electronic structure calculations that uses real-space grids, multigrid pre-conditioning, and subspace diagonalization to solve the Kohn-Sham equations. The code has been successfully used for a wide range of problems ranging from complex bulk materials to multifunctional electronic devices and biological systems. RMG makes efficient use of GPU accelerators, if present, but does not require them. Recent work has extended GPU support to systems with multiple GPU's per computational node, as well as optimized both CPU and GPU memory usage to enable large problem sizes, which are no longer limited by the memory of the GPU board. Additional enhancements include increased portability, scalability and performance. New versions of the code are regularly released at sourceforge.net/projects/rmgdft/. The releases include binaries for Linux, Windows and MacIntosh systems, automated builds for clusters using cmake, as well as versions adapted to the major supercomputing installations and platforms.

  16. SiGN-SSM: open source parallel software for estimating gene networks with state space models.

    Science.gov (United States)

    Tamada, Yoshinori; Yamaguchi, Rui; Imoto, Seiya; Hirose, Osamu; Yoshida, Ryo; Nagasaki, Masao; Miyano, Satoru

    2011-04-15

    SiGN-SSM is an open-source gene network estimation software able to run in parallel on PCs and massively parallel supercomputers. The software estimates a state space model (SSM), that is a statistical dynamic model suitable for analyzing short time and/or replicated time series gene expression profiles. SiGN-SSM implements a novel parameter constraint effective to stabilize the estimated models. Also, by using a supercomputer, it is able to determine the gene network structure by a statistical permutation test in a practical time. SiGN-SSM is applicable not only to analyzing temporal regulatory dependencies between genes, but also to extracting the differentially regulated genes from time series expression profiles. SiGN-SSM is distributed under GNU Affero General Public Licence (GNU AGPL) version 3 and can be downloaded at http://sign.hgc.jp/signssm/. The pre-compiled binaries for some architectures are available in addition to the source code. The pre-installed binaries are also available on the Human Genome Center supercomputer system. The online manual and the supplementary information of SiGN-SSM is available on our web site. tamada@ims.u-tokyo.ac.jp.

  17. Abundance of diurnal raptors on open space grasslands in an urbanized landscape

    Science.gov (United States)

    Berry, M.E.; Bock, C.E.; Haire, S.L.

    1998-01-01

    We conducted point counts of diurnal raptors on Boulder, Colorado, grasslands for three winters and summers, and compared results to landscape features of the count areas. Four wintering species were scarce on plots that included significant amounts of urban habitat, with a critical landscape threshold at about 5-7% urbanization: Bald Eagle (Haliaeetus leucocephalus), Ferruginous Hawk (Buteo regalis), Rough-legged Hawk (B. lagopus), and Prairie Falcon (Falco mexicanus). Counts of the first three species also were positively correlated with proximity of the count plots to the nearest colony of black-tailed prairie dogs (Cynomys ludovicianus). Two breeding species, the Red-tailed Hawk (B. jamaicensis) and Swainson's Hawk (B. swainsoni), were more abundant on plots dominated by lowland hayfields and tallgrass prairies, as opposed to upland mixed and shortgrass prairies. They, along with the ubiquitous American Kestrel (Falco sparverius), were not sensitive to the amounts of urbanization (up to 30%) that occurred in the landscapes sampled. Results of this study suggest that urban open space grasslands can support sizable populations of most diurnal raptors, as long as prey populations persist, but that some species are highly sensitive to landscape urbanization.

  18. Plutonium contamination in soils in open space and residential areas near Rocky Flats, Colorado.

    Science.gov (United States)

    Litaor, M I

    1999-02-01

    Spatial analysis of the 240Pu:239Pu isotopic ratio of 42 soil samples collected around Rocky Flats Plant near Golden, Colorado, was conducted to assess the effect of Rocky Flats Plant activity on the soil environment. Two probability maps that quantified the uncertainty of the spatial distribution of plutonium isotopic ratios were constructed using the sequential Gaussian simulation technique (sGs). Assuming a plutonium isotopic ratio range of 0.152+/-0.003 to 0.169+/-0.009 is characteristic to global fallout in Colorado, and a mean value of 0.155 is representative for the Rocky Flats Plant area, the main findings of the current work were (1) the areas northwest and southwest of Rocky Flats Plant exhibited a plutonium ratio > or = 0.155, thus were minimally impacted by the plant activity; (2) the study area east of Rocky Flats Plant (approximately 120 km2) exhibited a plutonium isotopic ratio open space and residential areas amounted to 111.2 GBq, with a standard error of estimate of 50.8 GBq.

  19. State Space Reduction of Linear Processes Using Control Flow Reconstruction

    NARCIS (Netherlands)

    Pol, van de Jaco; Timmer, Mark; Liu, Z.; Ravn, A.P.

    2009-01-01

    We present a new method for fighting the state space explosion of process algebraic specifications, by performing static analysis on an intermediate format: linear process equations (LPEs). Our method consists of two steps: (1) we reconstruct the LPE's control flow, detecting control flow parameters

  20. State Space Reduction of Linear Processes using Control Flow Reconstruction

    NARCIS (Netherlands)

    Pol, van de Jaco; Timmer, Mark

    2009-01-01

    We present a new method for fighting the state space explosion of process algebraic specifications, by performing static analysis on an intermediate format: linear process equations (LPEs). Our method consists of two steps: (1) we reconstruct the LPE's control flow, detecting control flow parameters

  1. Design and control considerations for industrial and space manipulators

    Science.gov (United States)

    Whitney, D. E.; Book, W. J.; Lynch, P. M.

    1974-01-01

    This paper is a progress report summarizing theoretical and practical results concerning integration of design and control aspects of manipulator arms for industrial or space applications. The relationships between task specifications, gross motions, fine motions, actuator type and location, size and strength of structural members, control servos and strategies, and overall design evaluation are briefly discussed, with some technical examples.

  2. Approximate controllability of neutral stochastic integrodifferential systems in Hilbert spaces

    Directory of Open Access Journals (Sweden)

    Krishnan Balachandran

    2008-12-01

    Full Text Available In this paper sufficient conditions are established for the controllability of a class of neutral stochastic integrodifferential equations with nonlocal conditions in abstract space. The Nussbaum fixed point theorem is used to obtain the controllability results, which extends the linear system to the stochastic settings with the help of compact semigroup. An example is provided to illustrate the theory.

  3. Design and control considerations for industrial and space manipulators

    Science.gov (United States)

    Whitney, D. E.; Book, W. J.; Lynch, P. M.

    1974-01-01

    This paper is a progress report summarizing theoretical and practical results concerning integration of design and control aspects of manipulator arms for industrial or space applications. The relationships between task specifications, gross motions, fine motions, actuator type and location, size and strength of structural members, control servos and strategies, and overall design evaluation are briefly discussed, with some technical examples.

  4. Model predictive control for cooperative control of space robots

    Science.gov (United States)

    Kannan, Somasundar; Alamdari, Seyed Amin Sajadi; Dentler, Jan; Olivares-Mendez, Miguel A.; Voos, Holger

    2017-01-01

    The problem of Orbital Manipulation of Passive body is discussed here. Two scenarios including passive object rigidly attached to robotic servicers and passive body attached to servicers through manipulators are discussed. The Model Predictive Control (MPC) technique is briefly presented and successfully tested through simulations on two cases of position control of passive body in the orbit.

  5. Design of pilot-assisted load control valve with load velocity control ability and fast opening feature

    Directory of Open Access Journals (Sweden)

    Haibo Xie

    2015-11-01

    Full Text Available This article presents a design of pilot-assisted load control valve with load velocity control ability and fast opening feature based on static and dynamic modeling. Traditional load control valves do not have the load velocity control ability and its opening feature is very poor because the high spring stiffness comes along with the pressure–spring balance–based principle. Some improvement has been done by employing a two-stage pressure–pressure balance principle to make a load control valve to achieve load velocity control ability while the opening feature was not improved much. In this design, another pressure–pressure balance principle is proposed to make the load control valve achieve load velocity control ability and fast opening closing feature at the same time. Static modeling method based on force balance and Bernoulli orifice pressure-flow equation is used to design the load velocity control ability of the valve. Dynamic modeling method based on Newton’s second law and fluid continuity equation is used to optimize the parameters to give the proposed load control valve a fast opening feature. An actual load control valve was developed according to the above methods and the test results show both good load velocity control ability and fast opening feature of the design, which validates the potentiality of the proposed design in many applications.

  6. Integrating Space Flight Resource Management Skills into Technical Lessons for International Space Station Flight Controller Training

    Science.gov (United States)

    Baldwin, Evelyn

    2008-01-01

    The Johnson Space Center s (JSC) International Space Station (ISS) Space Flight Resource Management (SFRM) training program is designed to teach the team skills required to be an effective flight controller. It was adapted from the SFRM training given to Shuttle flight controllers to fit the needs of a "24 hours a day/365 days a year" flight controller. More recently, the length reduction of technical training flows for ISS flight controllers impacted the number of opportunities for fully integrated team scenario based training, where most SFRM training occurred. Thus, the ISS SFRM training program is evolving yet again, using a new approach of teaching and evaluating SFRM alongside of technical materials. Because there are very few models in other industries that have successfully tied team and technical skills together, challenges are arising. Despite this, the Mission Operations Directorate of NASA s JSC is committed to implementing this integrated training approach because of the anticipated benefits.

  7. The influence of personal belief, agency mission and city size on open space decision making processes in three southwestern cities

    Science.gov (United States)

    Megan Friggens; Carol Raish; Deborah Finch; Alice McSweeney

    2015-01-01

    The southwest has experienced dramatic population increases over the last 30 years, a trend that is expected to continue. Open space conservation is important both from the standpoint of preserving ecosystem services as well as maintaining quality of life for urban populations. Federal agencies manage a large proportion of the public land in the Southwestern U.S. We...

  8. NASA's Controlled Environment Agriculture Testing for Space Habitats

    Science.gov (United States)

    Wheeler, Raymond M.

    2014-01-01

    NASA and other space agencies have an interest in using plants for human life support in space. The plants could provide food and O2 for the humans, while removing CO2 and helping purify wastewater. Studies to date have shown that a wide range of crops can be grown in controlled environment conditions envisioned for space. Light is a critical factor both for crop productivity and system power costs, and recent improvements in LEDs make them a preferred lighting option for space. Because space systems would be tightly closed, issues such as ethylene build-up and management must be considered. Ultimately, the costs and reliability of biological life support options must be compared with more conventional life support approaches. Findings to date suggest that about 20-25 sq. meters of crops could supply the O2 for one human, while about 50 sq. meters would be required for food (dietary calories).

  9. Control of free-flying space robot manipulator systems

    Science.gov (United States)

    Cannon, Robert H., Jr.

    1990-01-01

    New control techniques for self contained, autonomous free flying space robots were developed and tested experimentally. Free flying robots are envisioned as a key element of any successful long term presence in space. These robots must be capable of performing the assembly, maintenance, and inspection, and repair tasks that currently require human extravehicular activity (EVA). A set of research projects were developed and carried out using lab models of satellite robots and a flexible manipulator. The second generation space robot models use air cushion vehicle (ACV) technology to simulate in 2-D the drag free, zero g conditions of space. The current work is divided into 5 major projects: Global Navigation and Control of a Free Floating Robot, Cooperative Manipulation from a Free Flying Robot, Multiple Robot Cooperation, Thrusterless Robotic Locomotion, and Dynamic Payload Manipulation. These projects are examined in detail.

  10. Tethered actuator for vibration control of space structures

    Science.gov (United States)

    Fujii, H. A.; Sugimoto, Y.; Watanabe, T.; Kusagaya, T.

    2015-12-01

    Effectiveness of a micro-tension actuator for vibration control of such flexible space structures as the tethered space solar power satellites is experimentally studied on the ground. A flexible leverage is employed as the micro-tension actuator in order to control the microtension of tether. The flexible leverage is connected through a tether to the flexible beam as an experimental model of the flexible solar panel with the low first modal frequency of order 1 Hz. The nonlinearity of the flexible tether is taken into account for the vibration control since the tether becomes ineffective when it slacks, i.e., when it is tension-free. The feedback controller is designed by means of the Mission Function control algorithm. Flexural rigidity of the flexible leverage plays an important role in the vibration suppression and is studied experimentally to shed light on the effectiveness of the leverages with five different kinds of rigidity. The experimental results show not only the effect of the flexural rigidity of the flexible leverage on the control performance of the vibration suppression but also the importance of selection of the rigidity to control the vibration of tethered flexible space structures through the microtension of tethers in space.

  11. Space Weather Influence on Relative Motion Control using the Touchless Electrostatic Tractor

    Science.gov (United States)

    Hogan, Erik A.; Schaub, Hanspeter

    2016-09-01

    With recent interest in the use of electrostatic forces for contactless tugging and attitude control of noncooperative objects for orbital servicing and active debris mitigation, the need for a method of remote charge control arises. In this paper, the use of a directed electron beam for remote charge control is considered in conjunction with the relative motion control. A tug vehicle emits an electron beam onto a deputy object, charging it negatively. At the same time, the tug is charged positively due to beam emission, resulting in an attractive electrostatic force. The relative position feedback control between the tug and the passive debris object is studied subject to the charging being created through an electron beam. Employing the nominal variations of the GEO space weather conditions across longitude slots, two electrostatic tugging strategies are considered. First, the electron beam current is adjusted throughout the orbit in order to maximize this resulting electrostatic force. This open-loop control strategy compensates for changes in the nominally expected local space weather environment in the GEO region to adjust for fluctuations in the local plasma return currents. Second, the performance impact of using a fixed electron beam current on the electrostatic tractor is studied if the same natural space weather variations are assumed. The fixed electron beam current shows a minor performance penalty (<5 %) while providing a much simpler implementation that does not require any knowledge of local space weather conditions.

  12. Sensitivity and open-loop control of stochastic response in a noise amplifier flow: the backward-facing step

    CERN Document Server

    Boujo, Edouard

    2014-01-01

    The two-dimensional backward-facing step flow is a canonical example of noise amplifier flow: global linear stability analysis predicts that it is stable, but perturbations can undergo large amplification in space and time as a result of non-normal effects. This amplification potential is best captured by optimal transient growth analysis, optimal harmonic forcing, or the response to sustained noise. In view of reducing disturbance amplification in these globally stable open flows, a variational technique is proposed to evaluate the sensitivity of stochastic amplification to steady control. Existing sensitivity methods are extended in two ways to achieve a realistic representation of incoming noise: (i) perturbations are time-stochastic rather than time-harmonic, (ii) perturbations are localised at the inlet rather than distributed in space. This allows for the identification of regions where small-amplitude control is the most effective, without actually computing any controlled flows. In particular, passive...

  13. Sliding Mode Thermal Control System for Space Station Furnace Facility

    Science.gov (United States)

    Jackson Mark E.; Shtessel, Yuri B.

    1998-01-01

    The decoupled control of the nonlinear, multiinput-multioutput, and highly coupled space station furnace facility (SSFF) thermal control system is addressed. Sliding mode control theory, a subset of variable-structure control theory, is employed to increase the performance, robustness, and reliability of the SSFF's currently designed control system. This paper presents the nonlinear thermal control system description and develops the sliding mode controllers that cause the interconnected subsystems to operate in their local sliding modes, resulting in control system invariance to plant uncertainties and external and interaction disturbances. The desired decoupled flow-rate tracking is achieved by optimization of the local linear sliding mode equations. The controllers are implemented digitally and extensive simulation results are presented to show the flow-rate tracking robustness and invariance to plant uncertainties, nonlinearities, external disturbances, and variations of the system pressure supplied to the controlled subsystems.

  14. An expert system based intelligent control scheme for space bioreactors

    Science.gov (United States)

    San, Ka-Yiu

    1988-01-01

    An expert system based intelligent control scheme is being developed for the effective control and full automation of bioreactor systems in space. The scheme developed will have the capability to capture information from various resources including heuristic information from process researchers and operators. The knowledge base of the expert system should contain enough expertise to perform on-line system identification and thus be able to adapt the controllers accordingly with minimal human supervision.

  15. Active vibration control techniques for flexible space structures

    Science.gov (United States)

    Parlos, Alexander G.; Jayasuriya, Suhada

    1990-01-01

    Two proposed control system design techniques for active vibration control in flexible space structures are detailed. Control issues relevant only to flexible-body dynamics are addressed, whereas no attempt was made to integrate the flexible and rigid-body spacecraft dynamics. Both of the proposed approaches revealed encouraging results; however, further investigation of the interaction of the flexible and rigid-body dynamics is warranted.

  16. Control software analysis, Part I Open-loop properties

    CERN Document Server

    Feron, Eric

    2008-01-01

    As the digital world enters further into everyday life, questions are raised about the increasing challenges brought by the interaction of real-time software with physical devices. Many accidents and incidents encountered in areas as diverse as medical systems, transportation systems or weapon systems are ultimately attributed to "software failures". Since real-time software that interacts with physical systems might as well be called control software, the long litany of accidents due to real-time software failures might be taken as an equally long list of opportunities for control systems engineering. In this paper, we are interested only in run-time errors in those pieces of software that are a direct implementation of control system specifications: For well-defined and well-understood control architectures such as those present in standard textbooks on digital control systems, the current state of theoretical computer science is well-equipped enough to address and analyze control algorithms. It appears tha...

  17. "Festival of Flight Special": Opening Space for Next Generation Explorers. NASA CONNECT[TM]. [Videotape].

    Science.gov (United States)

    National Aeronautics and Space Administration, Hampton, VA. Langley Research Center.

    The National Aeronautics and Space Administration's (NASA) Space Launch Initiative (SLI) Program will ultimately move from the explorations of the Mercury, Gemini, Apollo, and Space Shuttle missions to a new period of pioneering in which people and businesses are more routinely traveling, working, and living in space. (Author/NB)

  18. A camera space control system for an automated forklift

    Energy Technology Data Exchange (ETDEWEB)

    Miller, R.K.; Stewart, D.G.; Brockman, W.H. (Iowa State Univ., Ames, IA (United States)); Skaar, S.B. (Univ. of Notre Dame, IN (United States). Dept. of Aerospace and Mechanical Engineering)

    1994-10-01

    The authors present experimental results on a method of camera space control applied to a mobile cart with an on-board robot, operated as a forklift. The objective is to extend earlier results to the task of the precise and robust three-dimensional object placement. The method is illustrated with a box stacking task. Camera space control does not rely on producing absolute position measurements. All measurements, estimates and control criteria are done relative to camera images in units of pixels. The resulting ''camera space'' technique is found to be very robust, i.e., extremely accurate modeling and calibration are not needed in order to achieve a precise result.

  19. Universal computer control system (UCCS) for space telerobots

    Science.gov (United States)

    Bejczy, Antal K.; Szakaly, Zoltan

    1987-01-01

    A universal computer control system (UCCS) is under development for all motor elements of a space telerobot. The basic hardware architecture and software design of UCCS are described, together with the rich motor sensing, control, and self-test capabilities of this all-computerized motor control system. UCCS is integrated into a multibus computer environment with direct interface to higher level control processors, uses pulsewidth multiplier power amplifiers, and one unit can control up to sixteen different motors simultaneously at a high I/O rate. UCCS performance capabilities are illustrated by a few data.

  20. Open questions in the present heliospheric research and challenges for upcoming space mission like IMAP

    Science.gov (United States)

    Fahr, H. J.

    2015-12-01

    Since the appearance of the first IBEX ENA fullsky maps in 2009 up to the present time it remained an open question what ENA sources are reponsible for the famous "IBEX-ribbon" feature. Both innerheliospheric and outerheliospheric ENA sources still today compete as reponsible candidates for that feature. Whether the ribbon-producing ENA`s are due to charge exchange processes inside or outside the heliopause is an outstanding question up to the present days. The answer, as I will show, will surely come with an extended energy range of the ENA detector and with a better time resolution in ENA maps, helping to control the reflection of temporal variations of solar wind flux patterns in ENA features as it all will be realized with IMAP.A second open question concerns the compressibility of the heliosheath plasma. Incompressibility prevails under very low Mach number flows or very high effective sound speeds, as could be realized by hot PUI`s or hot electrons downstream of the termination shock. Hot suprathermal electrons have been predicted, but not yet confirmed by VOYAGER measurements. At the low energy side of the spectrum this is explained by the negative charge-up of the spacecraft, at the medium energy range (0.5-1.0 MeV) shock-processed suprathermal electrons are likely to in fact explain the observations.Furthermore these electrons would directly influence the electrostatic wave characteristics in the heliosheath leading to unexpected propagation properties of such waves. To clarify on some of these points IMAP should have a sensitive electron detector which could monitor solar wind electron properties at passages of travelling shocks and thus prove the efficiency of shock processing.If in fact hot electrons have to be expected in the heliosheath, then electron impact ionization processes have to be studied in new details, and the question may arise whether also LISM helium under these new auspices becomes partially ionized when crossing the heliosheath.

  1. Controllable generation of partially coherent light pulses with direct space-to-time pulse shaper.

    Science.gov (United States)

    Torres-Company, Víctor; Mínguez-Vega, Gladys; Lancis, Jesús; Friberg, Ari T

    2007-06-15

    We demonstrate the possibility of creating user-defined partially coherent light pulses by means of a slight modification of the direct space-to-time pulse shaper. Specifically, we generate a mutual coherence function that corresponds to the independent-elementary-pulse representation model. The theoretical limits in the parameter of global coherence and the efficiency of the system are studied. Our result opens the door to a new way of quantum control in laser-assisted chemical reactions, namely, control by partial coherence.

  2. Adaptive Backstepping Controller Design for Leveling Control of an Underwater Platform Based on Joint Space

    Directory of Open Access Journals (Sweden)

    Zhi-Lin Zeng

    2014-01-01

    Full Text Available This paper focuses on high precision leveling control of an underwater heavy load platform, which is viewed as an underwater parallel robot on the basis of its work pattern. The kinematic of platform with deformation is analyzed and the dynamics model of joint space is established. An adaptive backstepping controller according to Lyapunov's function is proposed for leveling control of platform based on joint space. Furthermore, the “lowest point fixed angle error” leveling scheme called “chase” is chosen for leveling control of platform. The digital simulation and practical experiment of single joint space actuator are carried out, and the results show high precision servo control of joint space. On the basis of this, the platform leveling control simulation relies on the hardware-in-loop system. The results indicate that the proposed controller can effectively restrain the influence from system parameter uncertainties and external disturbance to realize high precision leveling control of the underwater platform.

  3. Open Spaces and Urban Ecosystem Services. Cooling Effect towards Urban Planning in South American Cities

    Directory of Open Access Journals (Sweden)

    Luis Inostroza

    2014-05-01

    Full Text Available Open space (OS is a key element in the provision of ecosystem services (ES in urban environments. Under a land cover-land use perspective, cities are incorporating into the expansion process to different types of surfaces: sealed, paved surfaces and OS. The first corresponds to a land cover change while the second, which includes bare soil, grass, forest or any other type of non-sealed surface, corresponds to a land use change, without physical transformations. As a land use change OS is able to keep fundamental pre-existing ecological properties. However, besides specific ecological characteristics, the overall capacity to provide ES depends also on the size, number and spatial distribution of OSs within the urban fabric. Those aspects which can determine the very ecological performance of urban ecosystem services (UES are not yet included in the current urban planning in Latin America. OS is still understood mainly as green infrastructure and related mostly with aesthetic and cultural benefits. On the contrary, under an ecological point of view, OS is capable to provide fundamental UES, which can be spatially assessed and analyzed. In this paper the provision of cooling services (CS is assessed in 2 South American cities: Lima and Santiago de Chile. The provision of CS is measured by means of a Remote Sensing-GIS-based method. Two aspects of CS are explored: (1 the current amount of existing OS; and (2 the trend of increasing/reducing CS within the urban tissue, in a dynamic assessment of spatial distribution and rates of OS incorporation to the continuous urban tissue. The aim is to analyze the CS generated by OS in those two cities. The analysis discusses the role of OS in the provision of CS, considering the current urban development trends and planning practice in these specific Latin American cities, highlighting the need to keep unsealed surfaces and increase in trees coverage, to retain the CS provision in certain levels.

  4. State-space control of prosthetic hand shape.

    Science.gov (United States)

    Velliste, M; McMorland, A J C; Diril, E; Clanton, S T; Schwartz, A B

    2012-01-01

    In the field of neuroprosthetic control, there is an emerging need for simplified control of high-dimensional devices. Advances in robotic technology have led to the development of prosthetic arms that now approach the look and number of degrees of freedom (DoF) of a natural arm. These arms, and especially hands, now have more controllable DoFs than the number of control DoFs available in many applications. In natural movements, high correlations exist between multiple joints, such as finger flexions. Therefore, discrepancy between the number of control and effector DoFs can be overcome by a control scheme that maps low-DoF control space to high-DoF joint space. Imperfect effectors, sensor noise and interactions with external objects require the use of feedback controllers. The incorporation of feedback in a system where the command is in a different space, however, is challenging, requiring a potentially difficult inverse high-DoF to low-DoF transformation. Here we present a solution to this problem based on the Extended Kalman Filter.

  5. Set point control in the state space setting

    DEFF Research Database (Denmark)

    Poulsen, Niels Kjølstad

    . The focus is in this report related to the problem of handling a set point or a constant reference in a state space setting. In principle just about any (state space control) design methodology may be applied. Here the presentation is based on LQ design, but other types such as poleplacement can be applied......This report is intented as a supplement or an extension to the material used in connection to or after the courses Stochastic Adaptive Control (02421) and Static and Dynamic Optimization (02711) given at the Department of Informatics and Mathematical Modelling, The Technical University of Denmark...

  6. Electronic controls and displays for a Space Station workstation

    Science.gov (United States)

    Busquets, A. M.; Parrish, R. V.; Hogge, T. W.

    1986-01-01

    A workstation to serve as a man/machine interface for one of the test beds used in the NASA-Space Station development effort is described which will also serve as a demonstrator of the advanced technologies anticipated for the Space Station workstation. Thin-film electroluminescent flat-panels may replace the presently used CRTs for image generation, and the development of multifunctional controls, advanced graphic generators, and videodisc technology are considered. A generalized window management algorithm will control the large volume of information required, and conventional office automation tools such as spread sheets and database managers will be applied to workstation image management.

  7. Integrated open loop control and design of a food storage room

    NARCIS (Netherlands)

    Mourik, van S.; Zwart, H.; Keesman, K.J.

    2009-01-01

    Usually, control design in a food storage room takes place after the plant has been designed. However, the performance of the plant connected to the controller might be improved by simultaneous design of the plant and the controller. In the case of open loop control, expressions that describe the dy

  8. An assessment of overall open-loop "gain" of CO2-ventilation feedback control system in hypoxia.

    Science.gov (United States)

    Masuyama, H; Akiyama, S; Honda, Y

    1985-01-01

    Overall open-loop gain of the CO2-ventilation feedback control system in hypoxia (GHCO2) was determined on 8 male and one female healthy subjects. They breathed in a closed circuit, and were subjected to the progressive hypoxia test. This procedure was first conducted without dead space (DS), then with 250, 500, and finally 750 ml DS, consecutively. GHCO2 was calculated by dividing the slope of the CO2 response curve (S) by that of the metabolic hyperbola (SL). GHCO2 was considerably larger than the overall open-loop gain of the O2-ventilation feedback control system (GO2) previously obtained. This was ascribed to the facts that S was larger than the slope of the hypoxia response curve, and that the absolute value of SL in GHCO2 was smaller than that in GO2.

  9. Overview of Carbon Dioxide Control Issues During International Space Station/Space Shuttle Joint Docked Operations

    Science.gov (United States)

    Matty, Christopher M.

    2010-01-01

    Crewed space vehicles have a common requirement to remove the carbon dioxide (CO2) created by the metabolic processes of the crew. The space shuttle [Space Transportation System (STS)] and International Space Station (ISS) each have systems in place that allow control and removal of CO2 from the habitable cabin environment. During periods in which the space shuttle is docked to the ISS, known as "joint docked operations," the space shuttle and ISS share a common atmosphere environment. During this period, an elevated amount of CO2 is produced through the combined metabolic activity of the STS and ISS crews. This elevated CO2 production, together with the large effective atmosphere created by collective volumes of the docked vehicles, creates a unique set of requirements for CO2 removal. This paper will describe individual CO2 control plans implemented by STS and ISS engineering teams, as well as the integrated plans used when both vehicles are docked. The paper will also discuss some of the issues and anomalies experienced by both engineering teams.

  10. Adaptive Correlation Space Adjusted Open-Loop Tracking Approach for Vehicle Positioning with Global Navigation Satellite System in Urban Areas

    Directory of Open Access Journals (Sweden)

    Hang Ruan

    2015-08-01

    Full Text Available For vehicle positioning with Global Navigation Satellite System (GNSS in urban areas, open-loop tracking shows better performance because of its high sensitivity and superior robustness against multipath. However, no previous study has focused on the effects of the code search grid size on the code phase measurement accuracy of open-loop tracking. Traditional open-loop tracking methods are performed by the batch correlators with fixed correlation space. The code search grid size, which is the correlation space, is a constant empirical value and the code phase measuring accuracy will be largely degraded due to the improper grid size, especially when the signal carrier-to-noise density ratio (C/N0 varies. In this study, the Adaptive Correlation Space Adjusted Open-Loop Tracking Approach (ACSA-OLTA is proposed to improve the code phase measurement dependent pseudo range accuracy. In ACSA-OLTA, the correlation space is adjusted according to the signal C/N0. The novel Equivalent Weighted Pseudo Range Error (EWPRE is raised to obtain the optimal code search grid sizes for different C/N0. The code phase measuring errors of different measurement calculation methods are analyzed for the first time. The measurement calculation strategy of ACSA-OLTA is derived from the analysis to further improve the accuracy but reduce the correlator consumption. Performance simulation and real tests confirm that the pseudo range and positioning accuracy of ASCA-OLTA are better than the traditional open-loop tracking methods in the usual scenarios of urban area.

  11. Thermal control system for Space Station Freedom photovoltaic power module

    Science.gov (United States)

    Hacha, Thomas H.; Howard, Laura

    1994-01-01

    The electric power for Space Station Freedom (SSF) is generated by the solar arrays of the photovoltaic power modules (PVM's) and conditioned, controlled, and distributed by a power management and distribution system. The PVM's are located outboard of the alpha gimbals of SSF. A single-phase thermal control system is being developed to provide thermal control of PVM electrical equipment and energy storage batteries. This system uses ammonia as the coolant and a direct-flow deployable radiator. The description and development status of the PVM thermal control system is presented.

  12. Preparation Of Control Space For Remeshing Of Polygonal Surfaces

    Directory of Open Access Journals (Sweden)

    Tomasz Jurczyk

    2013-01-01

    Full Text Available The subject of the article concerns the issues of remeshing, transforming a polygonal mesh into a triangular mesh adapted to surface. From the initial polygonal mesh the curvature of surface and boundary is retrieved and used to calculate a metric tensor varying in three-dimensional space. In the proposed approach the curvature is computed using local approximation of surfaces and curves on the basis of vertices of the polygonal mesh. An essential part of the presented remeshing procedure is creation of a control space structure based on the retrieved discrete data. The subsequent process of remeshing is then supervised by the contents of this auxiliary structure. The article presents various aspects related to the procedure of initialization, creation and adjusting the control space structure.

  13. Increasing Mission Reliability Using Open-Loop Control

    Science.gov (United States)

    1993-08-01

    Jersey, 1986. 2. J. J. DiStefano, A. R. Stubberud, and I. J. Williams , Feedback and Control Systems - Schaum’s Outline, McGraw-Hill, New York, 1967. 3. Z...ATTN: SMCRI-ENM THE PENTAGON ROCK ISLAND, IL 61299-5000 WASHINGTON. D.C. 20310-0103 MIAC/ CINDAS ADMINISTRATOR PURDUE UNIVERSITY DEFENSE TECHNICAL INFO

  14. A platform for dynamic simulation and control of movement based on OpenSim and MATLAB.

    Science.gov (United States)

    Mansouri, Misagh; Reinbolt, Jeffrey A

    2012-05-11

    Numerical simulations play an important role in solving complex engineering problems and have the potential to revolutionize medical decision making and treatment strategies. In this paper, we combine the rapid model-based design, control systems and powerful numerical method strengths of MATLAB/Simulink with the simulation and human movement dynamics strengths of OpenSim by developing a new interface between the two software tools. OpenSim is integrated with Simulink using the MATLAB S-function mechanism, and the interface is demonstrated using both open-loop and closed-loop control systems. While the open-loop system uses MATLAB/Simulink to separately reproduce the OpenSim Forward Dynamics Tool, the closed-loop system adds the unique feature of feedback control to OpenSim, which is necessary for most human movement simulations. An arm model example was successfully used in both open-loop and closed-loop cases. For the open-loop case, the simulation reproduced results from the OpenSim Forward Dynamics Tool with root mean square (RMS) differences of 0.03° for the shoulder elevation angle and 0.06° for the elbow flexion angle. MATLAB's variable step-size integrator reduced the time required to generate the forward dynamic simulation from 7.1s (OpenSim) to 2.9s (MATLAB). For the closed-loop case, a proportional-integral-derivative controller was used to successfully balance a pole on model's hand despite random force disturbances on the pole. The new interface presented here not only integrates the OpenSim and MATLAB/Simulink software tools, but also will allow neuroscientists, physiologists, biomechanists, and physical therapists to adapt and generate new solutions as treatments for musculoskeletal conditions. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Dynamic Control of Completely Free-Flying Space Robot System

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J.J. [Korea Advanced Energy Research Inst., Daeduk-Danji (Korea, Republic of). Korea Nuclear Safety Center; Xu, Y.; Kanade, T. [Carnegie-Mellon Univ., Pittsburgh, PA (United States). Robotics Inst.

    1993-03-01

    In this paper we discuss dynamic control of a completely- free-flying space robot system where the base attitude is not controlled. We first derive the system dynamic formulations in joint space and in inertia space, based on Lagrangian dynamics and linear and angular momentum conservation laws. The properties of completely free-flying robot system dynamics are studied. The nonlinear parameterization, one of the most important properties of the system dynamics, is demonstrated in theory and by a case study. Based on the system dynamic model in inertial space, globally stable dynamics control schemes are then proposed. Two algorithms are presented for the normal regulation problem and trajectory tracking applications. The PD algorithm is simple and easy to implement. The dynamic control algorithm has a fast and accurate system response even for the system with small mass/inertia ratio of the base with respect to the robot. The effectiveness of proposed algorithms is demonstrated by simulation studies. Future research work is identified. (author). 22 refs., 10 figs.

  16. Strategic directions of government control of national information space

    Directory of Open Access Journals (Sweden)

    Ірина Романівна Боднар

    2015-03-01

    Full Text Available The main directions of state information politics are considered. The legal framework and functioning of national information sphere is analyzed. The basic directions of government control of Ukraine's information space are considered. The approaches to the efficiency of the national information system are proposed

  17. Controlling floor heave of extraction opening by reinforcing sides and roof

    Institute of Scientific and Technical Information of China (English)

    WANG Wei-jun

    2005-01-01

    The effect of reinforcing roof, sides and floor corners to control floor heave of extraction opening was analyzed, It was proved by engineering practice and numerical simulation that reinforcing any part of surrounding rock have certainly control effect for floor heave, in the basis of this, the new way that roof, sides and floor corners were reinforced to control floor heave was put forward. Contrasting control result of reinforcing floor with this, it is determined that reinforcing is more suitable to control floor heave of extraction opening than reinforcing floor when advancing abutment pressure is in some range.

  18. A Backstepping Simple Adaptive Control Application to Flexible Space Structures

    Institute of Scientific and Technical Information of China (English)

    LIU Min; XU Shijie; HAN Chao

    2012-01-01

    Although the simple adaptive control (SAC) is widely studied both in theory and application in flexible space structure control and other control problems,it is restricted by the almost strictly positive real (ASPR) conditions.In most practical control problems,the ASPR conditions are not satisfied.Therefore,based on the SAC theory,this paper proposes a backstepping simple adaptive control algorithm which suits the system with arbitrary relative degree with no need of parallel feedforward compensator.The proposed control algorithm consists of decomposition of the arbitrary relative degree system into a known subsystem and an unknown ASPR subsystem which are eonneeted in cascade,design of constant outpul feedback controller for the known subsystem,and implementation of backstepping method and SAC of the unknown ASPR subsystem.Inheriting the characteristics of the SAC,this method can be adaptive online for the parameter uncertainties.Then,the application of the proposed controller to large flexible space structure with collocated sensors and actuators is studied,and the simulation results validate the proposed controller.It is a new strategy to apply the classical SAC to high relative degree plants.

  19. Supervised exercise therapy versus usual care for patellofemoral pain syndrome : an open label randomised controlled trial

    NARCIS (Netherlands)

    van Linschoten, R.; van Middelkoop, M.; Berger, M. Y.; Heintjes, E. M.; Verhaar, J. A. N.; Willemsen, S. P.; Koes, B. W.; Bierma-Zeinstra, S. M.

    2009-01-01

    Objective To assess the effectiveness of supervised exercise therapy compared with usual care with respect to recovery, pain, and function in patients with patellofemoral pain syndrome. Design Open label randomised controlled trial. Setting General practice and sport physician practice. Participants

  20. Supervised exercise therapy versus usual care for patellofemoral pain syndrome : an open label randomised controlled trial

    NARCIS (Netherlands)

    van Linschoten, R.; van Middelkoop, M.; Berger, M. Y.; Heintjes, E. M.; Verhaar, J. A. N.; Willemsen, S. P.; Koes, B. W.; Bierma-Zeinstra, S. M.

    2009-01-01

    Objective To assess the effectiveness of supervised exercise therapy compared with usual care with respect to recovery, pain, and function in patients with patellofemoral pain syndrome. Design Open label randomised controlled trial. Setting General practice and sport physician practice. Participants

  1. Sustaining Composition: Studying Content-Based, Ecological, and Economical Sustainability of Open-Source Textbooks through "Writing Spaces: Readings on Writing"

    Science.gov (United States)

    Munson, Margaret

    2013-01-01

    Writing programs in institutions of higher education work to prepare students for real-world writing within any field of study. The composition of "Writing Spaces: Readings on Writing" offers an open-source text for students, teachers, and policy-makers at all levels. Exposure to an open space for learning encourages access to information,…

  2. Moving targets: Promoting physical activity in public spaces via open streets in the US.

    Science.gov (United States)

    Hipp, J Aaron; Bird, Alyssa; van Bakergem, Margaret; Yarnall, Elizabeth

    2016-10-20

    Popularity of Open Streets, temporarily opening streets to communities and closing streets to vehicles, in the US has recently surged. As of January 2016, 122 cities have hosted an Open Streets program. Even with this great expansion, the sustainability of Open Streets remains a challenge in many cities and overall Open Streets in the US differ from their successful counterparts in Central and South America. Between summer 2015 and winter 2016, we reviewed the websites and social media of the 122 identified programs and interviewed 32 unique Open Streets programs. Websites and social media were reviewed for program initiation, number of Open Streets days, length of routes, duration of program, and reported participation. Interview questions focused on barriers and facilitators of expanding Open Streets and specific questioning regarding local evaluation activities. All interviews were transcribed verbatim and analyzed with constant comparative methodology. Over three-quarters of US Open Streets programs have been initiated since 2010, with median frequency of one time per year, 4h per date, and 5000-9999 participants. Seventy-seven percent of program routes are under 5km in length. Success of programs was measured by enthusiasm, attendance, social media, survey metrics, and sustainability. Thirteen of 32 program organizers expressed interest in expanding their programs to 12 dates per year, but noted consistent barriers to expansion including funding, permitting, and branding. Though many cities now host Open Streets programs, their ability to effect public health remains limited with few program dates per year. Coordinated efforts, especially around funding, permitting, and branding may assist in expanding program dates. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Discrete state space modeling and control of nonlinear unknown systems.

    Science.gov (United States)

    Savran, Aydogan

    2013-11-01

    A novel procedure for integrating neural networks (NNs) with conventional techniques is proposed to design industrial modeling and control systems for nonlinear unknown systems. In the proposed approach, a new recurrent NN with a special architecture is constructed to obtain discrete-time state-space representations of nonlinear dynamical systems. It is referred as the discrete state-space neural network (DSSNN). In the DSSNN, the outputs of the hidden layer neurons of the DSSNN represent the system's (pseudo) state. The inputs are fed to output neurons and the delayed outputs of the hidden layer neurons are fed to their inputs via adjustable weights. The discrete state space model of the actual system is directly obtained by training the DSSNN with the input-output data. A training procedure based on the back-propagation through time (BPTT) algorithm is developed. The Levenberg-Marquardt (LM) method with a trust region approach is used to update the DSSNN weights. Linear state space models enable to use well developed conventional analysis and design techniques. Thus, building a linear model of a system has primary importance in industrial applications. Thus, a suitable linearization procedure is proposed to derive the linear state space model from the nonlinear DSSNN representation. The controllability, observability and stability properties are examined. The state feedback controllers are designed with both the linear quadratic regulator (LQR) and the pole placement techniques. The regulator and servo control problems are both addressed. A full order observer is also designed to estimate the state variables. The performance of the proposed procedure is demonstrated by applying for both single-input single-output (SISO) and multiple-input multiple-output (MIMO) nonlinear control problems. © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

  4. Expose-R experiment on effects of open space condition on survivorship in dormant stages of aquatic invertebrates

    Science.gov (United States)

    Alekseev, Victor; Novikova, Nataliya; Levinskikh, Margarita; Sychev, Vladimir; Yusoff, Fatimah; Azuraidi, Osman

    2012-07-01

    Dormancy protects animals and plants in harsh environmental conditions from months up to hundred years. This phenomenon is perspective for space researches especially for interplanetary missions. Direct experiments in open space BYORYSK supported in principle the fact of survivorship of bacteria, fungi spores, seed of plants and crustacean dormant cysts. Even though the rate of survivorship in long-term treatments was low but good enough to conclude that biological invasion even to Mars is a real danger. As soon as the BYORYSK lunch was made of metal the possibility for resting stages to survive under UV treatment in vacuum without some protection was not clear. To test it an ESA and RSA equipment titled EXPOSE-R was applied. The EXPOSE-R facility was an external facility attached to the outside of the Zvezda Service Module in ISS in the end of November 2008. It had glace windows transparent for UV-radiation and possibility to measure temperature, space- and UV-radiation. Among a number of experiments requiring exposure to the open space environment it had a biological launch containing resting stages of terrestrial and aquatic organisms. These stages included dried ephippia of cladoceran Daphnia magna differentiated on size, dormant eggs of ostracode Eucypris ornate, cysts of fair-shrimp Streptocephalus torvicornis ( all from hemi desert Caspian area) and Artemis salina from salt lake Crimean populations. All dormant stages were kept in transparent to UV plastic bags placed in three layers. After about two years of exposing in open space dormant stages of 3 species A. salina, D. magna, S. torvicornis successfully survived at different scales but in second and third layers only . The highest level of survivorship was found in A. salina cysts. In preliminary land experiments that imitated land EXPOSE imitation of outside space station UV and vacuum conditions survivorship in resting eggs of D .magna, S. torvicornis and E. ornate was tested also. The total UV dose of

  5. An Approach to Autonomous Control for Space Nuclear Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    Wood, Richard Thomas [ORNL; Upadhyaya, Belle R. [University of Tennessee, Knoxville (UTK)

    2011-01-01

    Under Project Prometheus, the National Aeronautics and Space Administration (NASA) investigated deep space missions that would utilize space nuclear power systems (SNPSs) to provide energy for propulsion and spacecraft power. The initial study involved the Jupiter Icy Moons Orbiter (JIMO), which was proposed to conduct in-depth studies of three Jovian moons. Current radioisotope thermoelectric generator (RTG) and solar power systems cannot meet expected mission power demands, which include propulsion, scientific instrument packages, and communications. Historically, RTGs have provided long-lived, highly reliable, low-power-level systems. Solar power systems can provide much greater levels of power, but power density levels decrease dramatically at {approx} 1.5 astronomical units (AU) and beyond. Alternatively, an SNPS can supply high-sustained power for space applications that is both reliable and mass efficient. Terrestrial nuclear reactors employ varying degrees of human control and decision-making for operations and benefit from periodic human interaction for maintenance. In contrast, the control system of an SNPS must be able to provide continuous operatio for the mission duration with limited immediate human interaction and no opportunity for hardware maintenance or sensor calibration. In effect, the SNPS control system must be able to independently operate the power plant while maintaining power production even when subject to off-normal events and component failure. This capability is critical because it will not be possible to rely upon continuous, immediate human interaction for control due to communications delays and periods of planetary occlusion. In addition, uncertainties, rare events, and component degradation combine with the aforementioned inaccessibility and unattended operation to pose unique challenges that an SNPS control system must accommodate. Autonomous control is needed to address these challenges and optimize the reactor control design.

  6. Space Shuttle Main Engine control system. [hydraulic actuator with digital control

    Science.gov (United States)

    Seitz, P. F.; Searle, R. F.

    1973-01-01

    The Space Shuttle Main Engine is a reusable, high-performance rocket engine being developed by the Rocketdyne Div. of Rockwell International to satisfy the operational requirements of the Space Shuttle Orbiter Vehicle. The design incorporates a hydraulically actuated, closed-loop servosystem controlled and monitored by a programmable electronic digital controller. The controller accepts vehicle commands for the various engine operational phases, positions the appropriate valves, monitors the engine for the required performance precisions and conditions, and provides redundancy management.

  7. Changes in nutrient and antinutrient composition of Vigna racemosa flour in open and controlled fermentation

    OpenAIRE

    Difo, V. H.; Onyike, E.; D.A. Ameh; Njoku, G. C.; Ndidi, U. S.

    2014-01-01

    This study was conducted to investigate the effect of open and controlled fermentation on the proximate composition, mineral elements, antinutritional factors and flatulence-causing oligosaccharides in Vigna racemosa. The open fermentation was carried out using the microorganisms present in the atmosphere while the controlled fermentation was carried out using Aspergillus niger as a starter. The proximate composition of the Vigna racemosa, some anti-nutrients and the mineral elements were ana...

  8. Optimal boundary control of a tracking problem for a parabolic distributed system with open-loop control using evolutionary algorithms

    Directory of Open Access Journals (Sweden)

    Russel J Stonier

    2003-08-01

    Full Text Available In this paper we examine the application of evolutionary algorithms to find open-loop control solutions of the optimal control problem arising from the semidiscretisation of a linear parabolic tracking problem with boundary control. The solution is compared with the solutions obtained by methods based upon the variational equations of the Minimum Principle and the finite element method.

  9. Integrated structural control design of large space structures

    Energy Technology Data Exchange (ETDEWEB)

    Allen, J.J.; Lauffer, J.P.

    1995-01-01

    Active control of structures has been under intensive development for the last ten years. Reference 2 reviews much of the identification and control technology for structural control developed during this time. The technology was initially focused on space structure and weapon applications; however, recently the technology is also being directed toward applications in manufacturing and transportation. Much of this technology focused on multiple-input/multiple-output (MIMO) identification and control methodology because many of the applications require a coordinated control involving multiple disturbances and control objectives where multiple actuators and sensors are necessary for high performance. There have been many optimal robust control methods developed for the design of MIMO robust control laws; however, there appears to be a significant gap between the theoretical development and experimental evaluation of control and identification methods to address structural control applications. Many methods have been developed for MIMO identification and control of structures, such as the Eigensystem Realization Algorithm (ERA), Q-Markov Covariance Equivalent Realization (Q-Markov COVER) for identification; and, Linear Quadratic Gaussian (LQG), Frequency Weighted LQG and H-/ii-synthesis methods for control. Upon implementation, many of the identification and control methods have shown limitations such as the excitation of unmodelled dynamics and sensitivity to system parameter variations. As a result, research on methods which address these problems have been conducted.

  10. Integration of advanced teleoperation technologies for control of space robots

    Science.gov (United States)

    Stagnaro, Michael J.

    1993-01-01

    Teleoperated robots require one or more humans to control actuators, mechanisms, and other robot equipment given feedback from onboard sensors. To accomplish this task, the human or humans require some form of control station. Desirable features of such a control station include operation by a single human, comfort, and natural human interfaces (visual, audio, motion, tactile, etc.). These interfaces should work to maximize performance of the human/robot system by streamlining the link between human brain and robot equipment. This paper describes development of a control station testbed with the characteristics described above. Initially, this testbed will be used to control two teleoperated robots. Features of the robots include anthropomorphic mechanisms, slaving to the testbed, and delivery of sensory feedback to the testbed. The testbed will make use of technologies such as helmet mounted displays, voice recognition, and exoskeleton masters. It will allow tor integration and testing of emerging telepresence technologies along with techniques for coping with control link time delays. Systems developed from this testbed could be applied to ground control of space based robots. During man-tended operations, the Space Station Freedom may benefit from ground control of IVA or EVA robots with science or maintenance tasks. Planetary exploration may also find advanced teleoperation systems to be very useful.

  11. Command and control displays for space vehicle operations

    Science.gov (United States)

    Desjardins, Daniel D.; Zetocha, Paul; Aleva, Denise

    2010-04-01

    This paper shall examine several command and control facility display architectures supporting space vehicle operations, to include TacSat 2, TacSat 3, STPSat 2, and Communications Navigation Outage Forecasting System (CNOFS), located within the Research Development Test & Evaluation Support Complex (RSC) Satellite Operations Center 97 (SOC-97) at Kirtland Air Force Base. A principal focus is to provide an understanding for the general design class of displays currently supporting space vehicle command and control, e.g., custom, commercial-off-the-shelf, or ruggedized commercial-off-the-shelf, and more specifically, what manner of display performance capabilities, e.g., active area, resolution, luminance, contrast ratio, frame/refresh rate, temperature range, shock/vibration, etc., are needed for particular aspects of space vehicle command and control. Another focus shall be to address the types of command and control functions performed for each of these systems, to include how operators interact with the displays, e.g., joystick, trackball, keyboard/mouse, as well as the kinds of information needed or displayed for each function. [Comparison with other known command and control facilities, such as Cheyenne Mountain and NORAD Operations Center, shall be made.] Future, anticipated display systems shall be discussed.

  12. Control of water erosion and sediment in open cut coal mines in tropical areas

    Energy Technology Data Exchange (ETDEWEB)

    Ueda, T.; Nugraha, C.; Matsui, K.; Shimada, H.; Ichinose, M.; Gottfried, J. [Kyushu University, Fukuoka (Japan). Department of Earth Resources Engineering

    2005-07-01

    The purpose is to reduce the environmental impacts from open cut mining in tropical areas, such as Indonesia and Vietnam. Research conducted on methods for the control of water erosion and sediment from open cut coal mines is described. Data were collected on climate and weathering in tropical areas, mechanism of water erosion and sedimentation, characteristics of rocks in coal measures under wet conditions, water management at pits and haul roads and ramps, and construction of waste dumps and water management. The results will be applied to the optimum control and management of erosion and sediments in open cut mining. 6 refs., 8 figs.

  13. Study on mechanism of reinforcing sides to control floor heave of extraction opening

    Institute of Scientific and Technical Information of China (English)

    FENG Tao

    2005-01-01

    Roadway surrounding rock is a compound structure consisted of roof, floor and sides. The sides of extraction opening is the weak coal mass, which affect immediately the stability of floor. It was simulated by numerical calculation for the strength of sides coal to affect the floor heave, the higher strength of sides coal is, the lower degree of floor heave was. So it was put forward reinforcing sides to control floor heave of extraction opening,and it was proved by engineering practice that the floor heave of deep extraction opening can be controlled to a certain degree by reinforcing sides of roadway.

  14. An approach for an open control system for substations

    Energy Technology Data Exchange (ETDEWEB)

    Thang, W.Y.; Boussion, J.Y. [Electricite de France (France). Research and Development Div.; Peruzzo, B. [Schneider Electric (France); Hubner, R. [Siemens SA, 92 - Saint-Denis (France). Service Instrumentation Scientifique

    1997-12-31

    The aim of the PCCN project, a digital protection and control system, is to bring a new technological generation into use for the HM/MV substation protection and control systems. The project arose from the need to replace the current systems of EDF`s substations with fully digital facilities, mainly in order to improve their reliability, reduce their maintenance costs and to compensate equipment obsolescence. Thus, in 1992, the difficulty involved in replacing the existing systems, coupled with the incoming of industrial-grade digital products and the advantages of digital technology, led EDF to embark on the PCCN project for a new technological generation. This project consists of three phases: design, manufacturing and deployment. After reiterating the major industrial issues at stake for EDF, the paper will concentrate on the approach taken during the design phase in collaboration with two large-scale international industrial concerns, Siemens and Schneider Electric. It will then describe the action which resulted from these design studies and which is currently being carried out in the context of the manufacturing phase. (Author)

  15. Development of magnetostrictive active members for control of space structures

    Science.gov (United States)

    Johnson, Bruce G.; Avakian, Kevin M.; Fenn, Ralph C.; Gaffney, Monique S.; Gerver, Michael J.; Hawkey, Timothy J.; Boudreau, Donald J.

    1992-01-01

    The goal of this Phase 2 Small Business Innovative Research (SBIR) project was to determine the technical feasibility of developing magnetostrictive active members for use as truss elements in space structures. Active members control elastic vibrations of truss-based space structures and integrate the functions of truss structure element, actively controlled actuator, and sensor. The active members must control structural motion to the sub-micron level and, for many proposed space applications, work at cryogenic temperatures. Under this program both room temperature and cryogenic temperature magnetostrictive active members were designed, fabricated, and tested. The results of these performance tests indicated that room temperature magnetostrictive actuators feature higher strain, stiffness, and force capability with lower amplifier requirements than similarly sized piezoelectric or electrostrictive active members, at the cost of higher mass. Two different cryogenic temperature magnetostrictive materials were tested at liquid nitrogen temperatures, both with larger strain capability than the room temperature magnetostrictive materials. The cryogenic active member development included the design and fabrication of a cryostat that allows operation of the cryogenic active member in a space structure testbed.

  16. Impact of demographic trends on future development patterns and the loss of open space in the California Mojave Desert.

    Science.gov (United States)

    Gomben, Peter; Lilieholm, Robert; Gonzalez-Guillen, Manuel

    2012-02-01

    During the post-World War II era, the Mojave Desert Region of San Bernardino County, California, has experienced rapid levels of population growth. Over the past several decades, growth has accelerated, accompanied by significant shifts in ethnic composition, most notably from predominantly White non-Hispanic to Hispanic. This study explores the impacts of changing ethnicity on future development and the loss of open space by modeling ethnic propensities regarding family size and settlement preferences reflected by U.S. Census Bureau data. Demographic trends and land conversion data were obtained for seven Mojave Desert communities for the period between 1990 and 2001. Using a spatially explicit, logistic regression-based urban growth model, these data and trends were used to project community-specific future growth patterns from 2000 to 2020 under three future settlement scenarios: (1) an "historic" scenario reported in earlier research that uses a Mojave-wide average settlement density of 3.76 persons/ha; (2) an "existing" scenario based on community-specific settlement densities as of 2001; and (3) a "demographic futures" scenario based on community-specific settlement densities that explicitly model the Region's changing ethnicity. Results found that under the demographic futures scenario, by 2020 roughly 53% of within-community open space would remain, under the existing scenario only 40% would remain, and under the historic scenario model the communities would have what amounts to a deficit of open space. Differences in the loss of open space across the scenarios demonstrate the importance of considering demographic trends that are reflective of the residential needs and preferences of projected future populations.

  17. Interaction Network, State Space and Control in Social Dynamics

    CERN Document Server

    Aydogdu, Aylin; McQuade, Sean; Piccoli, Benedetto; Duteil, Nastassia Pouradier; Rossi, Francesco; Trélat, Emmanuel

    2016-01-01

    In the present chapter we study the emergence of global patterns in large groups in first and second-order multi-agent systems, focusing on two ingredients that influence the dynamics: the interaction network and the state space. The state space determines the types of equilibrium that can be reached by the system. Meanwhile, convergence to specific equilibria depends on the connectivity of the interaction network and on the interaction potential. When the system does not satisfy the necessary conditions for convergence to the desired equilibrium, control can be exerted, both on finite-dimensional systems and on their mean-field limit.

  18. Integrated multi-sensory control of space robot hand

    Science.gov (United States)

    Bejczy, A. K.; Kan, E. P.; Killion, R. R.

    1985-01-01

    Dexterous manipulation of a robot hand requires the use of multiple sensors integrated into the mechanical hand under distributed microcomputer control. Where space applications such as construction, assembly, servicing and repair tasks are desired of smart robot arms and robot hands, several critical drives influence the design, engineering and integration of such an electromechanical hand. This paper describes a smart robot hand developed at the Jet Propulsion Laboratory for experimental use and evaluation with the Protoflight Manipulator Arm (PFMA) at the Marshall Space Flight Center (MSFC).

  19. Neural Network Schemes in Cartesian Space Control of Robot Manipulators

    Directory of Open Access Journals (Sweden)

    Yiannis S. BOUTALIS

    2001-12-01

    Full Text Available In this paper we are studying the Cartesian space robot manipulator control problem by using Neural Networks (NN. Although NN compensation for model uncertainties has been traditionally carried out by modifying the joint torque/force of the robot, it is also possible to achieve the same objective by using the NN to modify other quantities of the controller. We present and evaluate four different NN controller designs to achieve disturbance rejection for an uncertain system. The design perspectives are dependent on the compensated position by NN. There are four quantities that can be compensated: torque , force F, control input U and the input trajectory Xd. By defining a unified training signal all NN control schemes have the same goal of minimizing the same objective functions. We compare the four schemes in respect to their control performance and the efficiency of the NN designs, which is demonstrated via simulations.

  20. Kane Method Based Dynamics Modeling and Control Study for Space Manipulator Capturing a Space Target

    Directory of Open Access Journals (Sweden)

    Yanhua Han

    2016-01-01

    Full Text Available Dynamics modeling and control problem of a two-link manipulator mounted on a spacecraft (so-called carrier freely flying around a space target on earth’s circular orbit is studied in the paper. The influence of the carrier’s relative movement on its manipulator is considered in dynamics modeling; nevertheless, that of the manipulator on its carrier is neglected with the assumption that the mass and inertia moment of the manipulator is far less than that of the carrier. Meanwhile, we suppose that the attitude control system of the carrier guarantees its side on which the manipulator is mounted points accurately always the space target during approaching operation. The ideal constraint forces can be out of consideration in dynamics modeling as Kane method is used. The path functions of the manipulator’s end-effector approaching the space target as well as the manipulator’s joints control torque functions are programmed to meet the soft touch requirement that the end-effector’s relative velocity to the space target is zero at touch moment. Numerical simulation validation is conducted finally.

  1. [Style of communication between mission control centers and space crews].

    Science.gov (United States)

    Iusupova, A K; Gushchin, V I; Shved, D M; Cheveleva, L M

    2011-01-01

    The article deals with a pilot investigation into the audio communication of cosmonauts with ground controllers. The purpose was to verify in space flight the patterns and trends revealed in model tests of intergroup communication, and to pinpoint the signature of multinational crew communication with 2 national mission control centers (MCCs). The investigation employed authors' content-analysis adapted to the scenario of long-duration mission. The investigation resulted in a phenomenon of double-loop ground-orbit communication, divergence, difference in opinion predictable from the concept formulated by G.T.Beregovoi. Also, there was a notable difference of expressions used by controllers of 2 MCCs.

  2. Morphological Control: A Design Principal for Applications in Space Science

    Science.gov (United States)

    Füchslin, R. M.; Dumont, E.; Flumini, D.; Fuchs, H. U.; Hauser, H.; Jaeger, C.; Scheidegger, S.; Schönenberger-Deuel, J.; Lichtensteiger, L.; Luchsinger, R.; Weyland, M.

    Designing robots for applications in space flight requires a different prioritization of design criteria than for systems operating on Earth. In this article, we argue that the field of soft robotics offers novel approaches meeting the specific requirements of space flight. We present one especially promising construction principle, so called Tensairity, in some detail. Tensairity, as the name suggests, takes ideas from Tensegrity, but uses inflatable structures instead of cables and struts. Soft robots pose substantial challenges with respect to control. One way to meet these challenges is given by the concept of morphological computation and control. Morphological computation can be loosely defined as the exploitation of the shape, material properties, and dynamics of a physical system to improve the efficiency of computation and to deal with systems for which it is difficult to construct a virtual representation using a kinematic model. We discuss fundamental aspects of morphological control and their relevance for space flight. Besides low weight, small consumption of space in the inactive state and advantageous properties with respect to intrinsic safety and energy consumption, we discuss how the blurring of the discrimination of hard- and software leads to control strategies that require only very little and very simple electronic circuitry (which is beneficial in an environment with high irradiation). Finally, we present a research strategy that bundles activities in space flight with research and development in medicine, especially for support systems for an aging population, that are faced with similar morphological computing challenges to astronauts. Such a combination meets the demands for research that is not only effective, but also efficient with respect to economic resources.

  3. Key characteristics for software for open architecture controllers

    Science.gov (United States)

    Pfeffer, Lawrence E.; Tran, Hy D.

    1997-01-01

    Software development time, cost, and ease of (re)use are now among the major issues in development of advanced machines, whether for machine tools, automation systems, or process systems. Two keys to reducing development time are powerful, user-friendly development tools and software architectures that provide clean, well-documented interfaces to the various real-time functions that such machines require. Examples of essential functions are signal conditioning, servo-control, trajectory generation, calibration/registration, coordination of a synchronous events, task sequencing, communication with external systems, and user interfaces. There are a number of existing standards that can help with software development, such as the IEEE POSIX standards for operating systems and real time services; software tools to compliment these standards are beginning to see use. This paper will detail some of the existing standards, some new tools, and development activities relevant to advanced, 'smart' machines.

  4. Learning Competences in Open Mobile Environments: A Comparative Analysis Between Formal and Non-Formal Spaces

    Directory of Open Access Journals (Sweden)

    Daniel Dominguez

    2014-07-01

    Full Text Available As a result of the increasing use of mobile devices in education, new approaches to define the learning competences in the field of digitally mediated learning have emerged. This paper examines these approaches, using data obtained from empirical research with a group of Spanish university students. The analysis is focused on the experiences of students in the use of mobile devices in both formal and open-informal educational contexts. The theoretical framework of the study is based on the ecological focus applied to explanatory models of digital literacy. As a result of the data it is possible to study this framework in depth, taking into account the theories defending an open view of digital literacy. The study may be of interest to instructional designers and researchers in the fields of open educational resources and technologies applied to education in open contexts.

  5. Open Source Patient-Controlled Analgesic Pump Requirements Documentation.

    Science.gov (United States)

    Larson, Brian R; Hatcliff, John; Chalin, Patrice

    2013-01-01

    The dynamic nature of the medical domain is driving a need for continuous innovation and improvement in techniques for developing and assuring medical devices. Unfortunately, research in academia and communication between academics, industrial engineers, and regulatory authorities is hampered by the lack of realistic non-proprietary development artifacts for medical devices. In this paper, we give an overview of a detailed requirements document for a Patient-Controlled Analgesic (PCA) pump developed under the US NSF's Food and Drug Administration (FDA) Scholar-in-Residence (SIR) program. This 60+ page document follows the methodology outlined in the US Federal Aviation Administrations (FAA) Requirements Engineering Management Handbook (REMH) and includes a domain overview, use cases, statements of safety & security requirements, and formal top-level system architectural description. Based on previous experience with release of a requirements document for a cardiac pacemaker that spawned a number of research and pedagogical activities, we believe that the described PCA requirements document can be an important research enabler within the formal methods and software engineering communities.

  6. Open-loop versus closed-loop control of MEMS devices: choices and issues

    Science.gov (United States)

    Borovic, B.; Liu, A. Q.; Popa, D.; Cai, H.; Lewis, F. L.

    2005-10-01

    From a controls point of view, micro electromechanical systems (MEMS) can be driven in an open-loop and closed-loop fashion. Commonly, these devices are driven open-loop by applying simple input signals. If these input signals become more complex by being derived from the system dynamics, we call such control techniques pre-shaped open-loop driving. The ultimate step for improving precision and speed of response is the introduction of feedback, e.g. closed-loop control. Unlike macro mechanical systems, where the implementation of the feedback is relatively simple, in the MEMS case the feedback design is quite problematic, due to the limited availability of sensor data, the presence of sensor dynamics and noise, and the typically fast actuator dynamics. Furthermore, a performance comparison between open-loop and closed-loop control strategies has not been properly explored for MEMS devices. The purpose of this paper is to present experimental results obtained using both open- and closed-loop strategies and to address the comparative issues of driving and control for MEMS devices. An optical MEMS switching device is used for this study. Based on these experimental results, as well as computer simulations, we point out advantages and disadvantages of the different control strategies, address the problems that distinguish MEMS driving systems from their macro counterparts, and discuss criteria to choose a suitable control driving strategy.

  7. Active absorption of acoustic wave using state-space control approach

    Science.gov (United States)

    Wu, Zhen; Varadan, Vijay K.; Varadan, Vasundara V.; Lee, Kwang Y.

    1994-05-01

    This paper presents a computer modeling and simulation of an active sound absorbing system with an optimal state-feedback controller. First, a state-space model is developed to describe one-dimensional sound reflection and transmission in the time domain. In the model derivation, the difficulty of discretizing the wave equation in an unbounded region is overcome by combining the finite-difference and analytical solutions. Numerical simulation of the open- loop model response is performed, which shows a good agreement with the well known frequency domain solutions. Second, a state-feedback controller including a linear quadratic regulator and a Kalman filter type state-estimator is designed using the optimal control theory. Numerical simulation of the closed-loop model response of an active sound control system containing two sensors and one actuator is presented. It is shown that a broadband attenuation of more than 30 dB over 2 octaves has been reached.

  8. Level of Abstraction and Feelings of Presence in Virtual Space: Business English Negotiation in Open Wonderland

    Science.gov (United States)

    Chen, Judy F.; Warden, Clyde A.; Tai, David Wen-Shung; Chen, Farn-Shing; Chao, Chich-Yang

    2011-01-01

    Virtual spaces allow abstract representations of reality that not only encourage student self-directed learning but also reinforce core content of the learning objective through visual metaphors not reproducible in the physical world. One of the advantages of such a space is the ability to escape the restrictions of the physical classroom, yet…

  9. Galerkin approximations of nonlinear optimal control problems in Hilbert spaces

    Directory of Open Access Journals (Sweden)

    Mickael D. Chekroun

    2017-07-01

    Full Text Available Nonlinear optimal control problems in Hilbert spaces are considered for which we derive approximation theorems for Galerkin approximations. Approximation theorems are available in the literature. The originality of our approach relies on the identification of a set of natural assumptions that allows us to deal with a broad class of nonlinear evolution equations and cost functionals for which we derive convergence of the value functions associated with the optimal control problem of the Galerkin approximations. This convergence result holds for a broad class of nonlinear control strategies as well. In particular, we show that the framework applies to the optimal control of semilinear heat equations posed on a general compact manifold without boundary. The framework is then shown to apply to geoengineering and mitigation of greenhouse gas emissions formulated here in terms of optimal control of energy balance climate models posed on the sphere $\\mathbb{S}^2$.

  10. Multifunctional Cooling Garment for Space Suit Environmental Control

    Science.gov (United States)

    Izenson, Michael; Chen, Weibo; Phillips, Scott; Chepko, Ariane; Bue, Grant; Ferl, Janet; Cencer, Daniel

    2015-01-01

    Future manned space exploration missions will require space suits with capabilities beyond the current state of the art. Portable Life Support Systems for these future space suits face daunting challenges, since they must maintain healthy and comfortable conditions inside the suit for long-duration missions while minimizing weight and water venting. We have demonstrated the feasibility of an innovative, multipurpose garment for thermal and humidity control inside a space suit pressure garment that is simple, rugged, compact, and lightweight. The garment is a based on a conventional liquid cooling and ventilation garment (LCVG) that has been modified to directly absorb latent heat as well as sensible heat. This hybrid garment will prevent buildup of condensation inside the pressure garment, prevent loss of water by absorption in regenerable CO2 removal beds, and conserve water through use of advanced lithium chloride absorber/radiator (LCAR) technology for nonventing heat rejection. We have shown the feasibility of this approach by sizing the critical components for the hybrid garment, developing fabrication methods, building and testing a proof-of-concept system, and demonstrating by test that its performance is suitable for use in space suit life support systems.

  11. [Development of open cycling air pressure control system used for glaucoma research].

    Science.gov (United States)

    Zhang, Hong; Li, Gui-gang; Wang, Xue-fang; Hu, Wei-kun; Xie, Er-juan; Chen, Lian-yi; Shan, Chang-mei; Zhao, Guo-hong

    2006-06-01

    To develop and set up a new culture system, which can apply pressure to cultured cells with open cycling air. The effects of this new system on the pH value, HCO(3)(-) concentration, O(2) pressure (pO(2)), CO2 pressure (pCO(2)) and the proliferation of retinal pigment epithelium (RPE) were tested to evaluate its efficiency in the study of glaucoma. In the open cycling air pressure control culture system, the pressure inside the culture flasks was controlled by increase or decrease of the perfuse airflow. The influence of different culture systems (normal pressure culture system, open cycling air pressure control system and occlusive pressure control system) on the pH value, HCO(3)(-) concentration, pO(2), pCO(2) and proliferation of RPE were tested. The data were analyzed with SPSS software. The open cycling air pressure control culture system worked effectively, the pressure inside the culture flask can be controlled from 0 to 100 mm Hg. The difference of pH value, HCO(3)(-) concentration, pO(2), and pCO(2) of culture medium and the proliferation of RPE between normal pressure culture system and open cycling air pressure control system were not significant (P = 0.927, 0.887, 0.818, 0.770, 0.719, respectively). There was significant difference in these data between normal pressure culture system and occlusive pressure control system (P = 0.001, 0.000, 0.000, 0.000, 0.000, respectively). A new designed standard culture system applying pressure to cells with open cycling air was effective at pressure controlling and pH value, HCO(3)(-) concentration, pO(2) and pCO(2) controlling. This system may act as an ideal model in the experimental study of glaucoma.

  12. Mechanical stratigraphic controls on natural fracture spacing and penetration

    Science.gov (United States)

    McGinnis, Ronald N.; Ferrill, David A.; Morris, Alan P.; Smart, Kevin J.; Lehrmann, Daniel

    2017-02-01

    Fine-grained low permeability sedimentary rocks, such as shale and mudrock, have drawn attention as unconventional hydrocarbon reservoirs. Fracturing - both natural and induced - is extremely important for increasing permeability in otherwise low-permeability rock. We analyze natural extension fracture networks within a complete measured outcrop section of the Ernst Member of the Boquillas Formation in Big Bend National Park, west Texas. Results of bed-center, dip-parallel scanline surveys demonstrate nearly identical fracture strikes and slight variation in dip between mudrock, chalk, and limestone beds. Fracture spacing tends to increase proportional to bed thickness in limestone and chalk beds; however, dramatic differences in fracture spacing are observed in mudrock. A direct relationship is observed between fracture spacing/thickness ratio and rock competence. Vertical fracture penetrations measured from the middle of chalk and limestone beds generally extend to and often beyond bed boundaries into the vertically adjacent mudrock beds. In contrast, fractures in the mudrock beds rarely penetrate beyond the bed boundaries into the adjacent carbonate beds. Consequently, natural bed-perpendicular fracture connectivity through the mechanically layered sequence generally is poor. Fracture connectivity strongly influences permeability architecture, and fracture prediction should consider thin bed-scale control on fracture heights and the strong lithologic control on fracture spacing.

  13. Attention control learning in the decision space using state estimation

    Science.gov (United States)

    Gharaee, Zahra; Fatehi, Alireza; Mirian, Maryam S.; Nili Ahmadabadi, Majid

    2016-05-01

    The main goal of this paper is modelling attention while using it in efficient path planning of mobile robots. The key challenge in concurrently aiming these two goals is how to make an optimal, or near-optimal, decision in spite of time and processing power limitations, which inherently exist in a typical multi-sensor real-world robotic application. To efficiently recognise the environment under these two limitations, attention of an intelligent agent is controlled by employing the reinforcement learning framework. We propose an estimation method using estimated mixture-of-experts task and attention learning in perceptual space. An agent learns how to employ its sensory resources, and when to stop observing, by estimating its perceptual space. In this paper, static estimation of the state space in a learning task problem, which is examined in the WebotsTM simulator, is performed. Simulation results show that a robot learns how to achieve an optimal policy with a controlled cost by estimating the state space instead of continually updating sensory information.

  14. Automated electric power management and control for Space Station Freedom

    Science.gov (United States)

    Dolce, James L.; Mellor, Pamela A.; Kish, James A.

    1990-01-01

    A comprehensive automation design is being developed for Space Station Freedom's electric power system. It strives to increase station productivity by applying expert systems and conventional algorithms to automate power system operation. An integrated approach to the power system command and control problem is defined and used to direct technology development in: diagnosis, security monitoring and analysis, battery management, and cooperative problem-solving for resource allocation. The prototype automated power system is developed using simulations and test-beds.

  15. Man-Machine Control of Space Robots under Uncertainty

    OpenAIRE

    Kanata, S.

    2008-01-01

    Control problem of space robots is characterized by several challenges. The first one is that the area is full of uncertainties due to lack of information. Another difficulty is tasksharing between an operator and a partly autonomous robot. Moreover, there are several constrains on the robot operations, including communication delay and an appropriate temperature at which robot can work. Design of the robots navigation should be based on consideration of trade-offs between several conf...

  16. Robust Task Space Trajectory Tracking Control of Robotic Manipulators

    Science.gov (United States)

    Galicki, M.

    2016-08-01

    This work deals with the problem of the accurate task space trajectory tracking subject to finite-time convergence. Kinematic and dynamic equations of a redundant manipulator are assumed to be uncertain. Moreover, globally unbounded disturbances are allowed to act on the manipulator when tracking the trajectory by the end-effector. Furthermore, the movement is to be accomplished in such a way as to reduce both the manipulator torques and their oscillations thus eliminating the potential robot vibrations. Based on suitably defined task space non-singular terminal sliding vector variable and the Lyapunov stability theory, we propose a class of chattering-free robust controllers, based on the estimation of transpose Jacobian, which seem to be effective in counteracting both uncertain kinematics and dynamics, unbounded disturbances and (possible) kinematic and/or algorithmic singularities met on the robot trajectory. The numerical simulations carried out for a redundant manipulator of a SCARA type consisting of the three revolute kinematic pairs and operating in a two-dimensional task space, illustrate performance of the proposed controllers as well as comparisons with other well known control schemes.

  17. Sensorless speed control of a five-phase induction machine under open-phase condition

    Directory of Open Access Journals (Sweden)

    Ahmed S. Morsy

    2014-05-01

    Full Text Available Recently, multiphase machines have been promoted as competitors to their three-phase counterparts in high-power safety-critical drive applications. Among numerous advantages of multiphase induction machine (IM drives, self-starting and operation under open phase(s stand as the most salient features. With open phase(s, optimal current control provides disturbance- free operation given a set of objective functions. Although hysteresis current control was merely employed in the literature as it offers a simple controller structure to control the remaining healthy phases, it is not suitable for high-power applications. In the literature, multiple synchronous reference frame (dq control can be an alternative; however, it requires back and forth transformations with several calculations and additional sophistication. In this paper, a simple technique employing adaptive proportional resonant (PR current controllers is presented to control a five-phase IM under open-phase conditions. Results for both volt/hertz (V/f and field oriented control (FOC systems are presented. Moreover, sensorless operation under fault condition is also demonstrated by estimating the machine speed using a rotor flux-based model reference adaptive system (MRAS speed estimator. The proposed controllers are experimentally verified and compared. Although FOC provides better dynamic performance, V/f control offers a simpler control structure and a lower number of PR controllers.

  18. Cursor Control using Smartphone in Large Display Space

    Institute of Scientific and Technical Information of China (English)

    Sungbae; Kim; Sungkuk; Chun; Kwangj; in; Hong; Keechul; Jung

    2010-01-01

    <正>We present a novel approach as a smartphone based interface that enables the users to control the cursor position in large display space.In the proposed method, computational techniques using image processing and accelerometer processing methodology serves as the core engine for fine cursor control.Unlike previous positioning mechanisms based on image processing,the proposed system is free from restraint of movement with velocity.For the implementation of our system,we combine the block matching algorithm for optical flow with three-axis acceleration to improve an accuracy and clutch.

  19. An open-plus-closed-loop control for chaotic Mathieu-Duffing oscillator

    Institute of Scientific and Technical Information of China (English)

    Jian-he SHEN; Shu-hui CHEN

    2009-01-01

    By using the idea of open-plus-closed-loop(OPCL) control, a controller com-posed of an external excitation and a linear feedback is designed to entrain chaotic tra-jectories of Mathieu-Duffing oscillator to its periodic and higher periodic orbits. The global basin of entrainment of this open-plus-closed-loop control is proved by combining the Lyapunov stability theory with a comparative theorem of initial value problems for second-order ordinary differential equations. Numerical simulations are performed to ver-ify the theoretical results.

  20. An Assessment of Educational Benefits from the OpenOrbiter Space Program

    Directory of Open Access Journals (Sweden)

    David Whalen

    2013-07-01

    Full Text Available This paper analyzes the educational impact of the OpenOrbiter Small Spacecraft Development Initiative, a CubeSat development program underway at the University of North Dakota. OpenOrbiter includes traditional STEM activities (e.g., spacecraft engineering, software development; it also incorporates students from non-STEM disciplines not generally involved in aerospace engineering projects such as management, entrepreneurship, education and fine arts. The value of the program to participants is analyzed quantitatively, in terms of improvement related to five key learning objectives.

  1. Recovery Act: Water Heater ZigBee Open Standard Wireless Controller

    Energy Technology Data Exchange (ETDEWEB)

    Butler, William P. [Emerson Electric Co., St. Louis, MO (United States); Buescher, Tom [Emerson Electric Co., St. Louis, MO (United States)

    2014-04-30

    The objective of Emerson's Water Heater ZigBee Open Standard Wireless Controller is to support the DOE's AARA priority for Clean, Secure Energy by designing a water heater control that levels out residential and small business peak electricity demand through thermal energy storage in the water heater tank.

  2. An Autonomous Underwater Vehicle Simulation Using Linear Quadratic Servo Based on Open Control Platform

    Directory of Open Access Journals (Sweden)

    Nanang Syahroni

    2012-01-01

    Full Text Available This paper presents an optimal regulator for depth control simulation of an autonomous underwater vehicle (AUV using a new approach of decentralized system environment called open control platform (OCP. Simulation results are presented to demonstrate performance of the proposed method.

  3. Design of a real-time open architecture controller for reconfigurable machine tool

    CSIR Research Space (South Africa)

    Masekamela, I

    2008-06-01

    Full Text Available modular structure in form of modular machines and open architecture controllers that can quickly change the physical structure and appropriately adjust the control system to adapt to the new production requirements. The paper aims to present the design...

  4. Residence space/graphic space: engravings in the open air in the municipality of La Hinojosa (Cuenca

    Directory of Open Access Journals (Sweden)

    Bueno Ramírez, Primitiva

    1998-06-01

    Full Text Available The work that now we present is based on the analysis of graphic designs, their location and their relationship to the environment, in the municipality of La Hinojosa Cuenca, a place where we have well documented occupations of the Copper and Bronze Ages. Our aim is to understand these engravings as part of the expressions of peninsular Schematic Art, in this case associated with an occupational context, and to provide elements for the comprehension of its message in a broader context that includes occupational contexts for other open aire engravings in the Iberian Peninsula.

    El trabajo que ahora presentamos se basa en el análisis de las grafías, su ubicación en el soporte y su relación con el entorno, en una zona concreta, el término de La Hinojosa, en Cuenca, lugar en el que tenemos bien documentadas ocupaciones calcolíticas y de la Edad del Bronce. Nuestra propuesta es la de comprender dichos grabados como una parte de las expresiones del Arte Esquemático peninsular, en este caso asociadas a un contexto habitacional y, a partir de ahí, aportar elementos para la comprensión de su "mensaje" desde una perspectiva más amplia que incluye otros contextos habitacionales para conjuntos de grabados al aire libre en la Península Ibérica.

  5. Pylogeny: an open-source Python framework for phylogenetic tree reconstruction and search space heuristics

    OpenAIRE

    Alexander Safatli; Christian Blouin

    2015-01-01

    Summary. Pylogeny is a cross-platform library for the Python programming language that provides an object-oriented application programming interface for phylogenetic heuristic searches. Its primary function is to permit both heuristic search and analysis of the phylogenetic tree search space, as well as to enable the design of novel algorithms to search this space. To this end, the framework supports the structural manipulation of phylogenetic trees, in particular using rearrangement operator...

  6. An acquisition control for the laser interferometer space antenna

    Energy Technology Data Exchange (ETDEWEB)

    Maghami, P G [NASA Goddard Space Flight Center, Guidance, Navigation and Control Division, Greenbelt, MD 20771 (United States); Hyde, T T [NASA Goddard Space Flight Center, Guidance, Navigation and Control Division, Greenbelt, MD 20771 (United States); Kim, J [Swales Aerospace, Inc., Greenbelt, MD 20771 (United States)

    2005-05-21

    The Laser Interferometer Space Antenna mission is a planned gravitational wave detector consisting of three spacecraft in heliocentric orbit. Laser interferometry is used to measure distance fluctuations between test masses aboard each spacecraft to the picometre level over a 5 million km separation. The disturbance reduction system comprises the pointing and positioning control of the spacecraft, electrostatic suspension control of the test masses and point-ahead and acquisition control. This paper presents an approach for the acquisition control of the LISA formation. The approach establishes one link at a time. For each link, it defocuses the incoming beams to make its light detectable by the receiving spacecraft. Simulations are performed to demonstrate the feasibility of the proposed approach.

  7. Hyperbaric environmental control assembly for the Space Station Freedom airlock

    Science.gov (United States)

    Rubly, Robert P.; Schimenti, Dan

    The hyperbaric environmental control assembly (HECA) monitors and controls temperature, humidity and CO2 levels in the Space Station Freedom airlock when the airlock is used for extravehicular activity (EVA) prebreathing campouts and as a hyperbaric treatment facility. Prebreathing is required prior to extravehicular activity due to the differential between the station nominal pressure and the EVA suit pressure. Hyperbaric treatment is required in the event of decompression sickness. The HECA consists of an atmosphere recirculation circuit which provides air circulation and temperature control, and a separate CO2 and humidity control circuit. CO2 and latent water production rates have been calculated from established metabolic profiles for both campout and hyperbaric protocols. An analytical model has been used to predict carbon dioxide and humidity levels as functions of initial crewlock conditions and the specified loads. This model has demonstrated the suitability and robustness of the dual-bed molecular sieve system for the HECA.

  8. Practical Application of Neural Networks in State Space Control

    DEFF Research Database (Denmark)

    Bendtsen, Jan Dimon

    In the present thesis we address some problems in discrete-time state space control of nonlinear dynamical systems and attempt to solve them using generic nonlinear models based on artificial neural networks. The main aim of the work is to examine how well such control algorithms perform when...... applied to a realistic process. The thesis therefore strives to provide a thorough treatment of two classes of neural network-based controllers, and to make a rigorous comparison between them and a classical linear controller. Thus, the thesis starts out with a short review of some relevant system...... theoretic notions followed by a detailed description of the topology, neuron functions and learning rules of the two types of neural networks treated in the thesis, the multilayer perceptron and the neurofuzzy networks. In both cases, a Least Squares second-order gradient method is used to train...

  9. Survey of orbital dynamics and control of space rendezvous

    Institute of Scientific and Technical Information of China (English)

    Luo Yazhong; Zhang Jin; Tang Guojin

    2014-01-01

    Rendezvous orbital dynamics and control (RODC) is a key technology for operating space rendezvous and docking missions. This paper surveys the studies on RODC. Firstly, the basic relative dynamics equation set is introduced and its improved versions are evaluated. Secondly, studies on rendezvous trajectory optimization are commented from three aspects:the linear rendez-vous, the nonlinear two-body rendezvous, and the perturbed and constrained rendezvous. Thirdly, studies on relative navigation are briefly reviewed, and then close-range control methods including automated control, manual control, and telecontrol are analyzed. Fourthly, advances in rendezvous trajectory safety and robust analysis are surveyed, and their applications in trajectory optimization are discussed. Finally, conclusions are drawn and prospects of studies on RODC are presented.

  10. Adaptive Task-Space Cooperative Tracking Control of Networked Robotic Manipulators Without Task-Space Velocity Measurements.

    Science.gov (United States)

    Liang, Xinwu; Wang, Hesheng; Liu, Yun-Hui; Chen, Weidong; Hu, Guoqiang; Zhao, Jie

    2016-10-01

    In this paper, the task-space cooperative tracking control problem of networked robotic manipulators without task-space velocity measurements is addressed. To overcome the problem without task-space velocity measurements, a novel task-space position observer is designed to update the estimated task-space position and to simultaneously provide the estimated task-space velocity, based on which an adaptive cooperative tracking controller without task-space velocity measurements is presented by introducing new estimated task-space reference velocity and acceleration. Furthermore, adaptive laws are provided to cope with uncertain kinematics and dynamics and rigorous stability analysis is given to show asymptotical convergence of the task-space tracking and synchronization errors in the presence of communication delays under strongly connected directed graphs. Simulation results are given to demonstrate the performance of the proposed approach.

  11. Niches in the urban forest: Organizations and their role in acquiring metropolitan open space.

    Science.gov (United States)

    Jane A. Ruliffson; Paul H. Gobster; Robert G. Haight; Francis R. Homans

    2002-01-01

    As a response strategy to minimize the impacts of urban sprawl, public and private organizations are striving to acquire open lands that will contribute to a resilient and multifunctional urban forest. In the Chicago metropolitan region, we interviewed representatives of 15 organizations to understand the land acquisition process--the structures and functions of...

  12. Panoramic Stereoscopic Video System for Remote-Controlled Robotic Space Operations Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Phase I project will demonstrate the feasibility of providing panoramic stereoscopic images for remote-controlled robotic space operations using three...

  13. Generalized space vector control for current source inverters and rectifiers

    Directory of Open Access Journals (Sweden)

    Roseline J. Anitha

    2016-06-01

    Full Text Available Current source inverters (CSI is one of the widely used converter topology in medium voltage drive applications due to its simplicity, motor friendly waveforms and reliable short circuit protection. The current source inverters are usually fed by controlled current source rectifiers (CSR with a large inductor to provide a constant supply current. A generalized control applicable for both CSI and CSR and their extension namely current source multilevel inverters (CSMLI are dealt in this paper. As space vector pulse width modulation (SVPWM features the advantages of flexible control, faster dynamic response, better DC utilization and easy digital implementation it is considered for this work. This paper generalizes SVPWM that could be applied for CSI, CSR and CSMLI. The intense computation involved in framing a generalized space vector control are discussed in detail. The algorithm includes determination of band, region, subregions and vectors. The algorithm is validated by simulation using MATLAB /SIMULINK for CSR 5, 7, 13 level CSMLI and for CSR fed CSI.

  14. Unexpected Control Structure Interaction on International Space Station

    Science.gov (United States)

    Gomez, Susan F.; Platonov, Valery; Medina, Elizabeth A.; Borisenko, Alexander; Bogachev, Alexey

    2017-01-01

    On June 23, 2011, the International Space Station (ISS) was performing a routine 180 degree yaw maneuver in support of a Russian vehicle docking when the on board Russian Segment (RS) software unexpectedly declared two attitude thrusters failed and switched thruster configurations in response to unanticipated ISS dynamic motion. Flight data analysis after the maneuver indicated that higher than predicted structural loads had been induced at various locations on the United States (U.S.) segment of the ISS. Further analysis revealed that the attitude control system was firing thrusters in response to both structural flex and rigid body rates, which resonated the structure and caused high loads and fatigue cycles. It was later determined that the thruster themselves were healthy. The RS software logic, which was intended to react to thruster failures, had instead been heavily influenced by interaction between the control system and structural flex. This paper will discuss the technical aspects of the control structure interaction problem that led to the RS control system firing thrusters in response to structural flex, the factors that led to insufficient preflight analysis of the thruster firings, and the ramifications the event had on the ISS. An immediate consequence included limiting which thrusters could be used for attitude control. This complicated the planning of on-orbit thruster events and necessitated the use of suboptimal thruster configurations that increased propellant usage and caused thruster lifetime usage concerns. In addition to the technical aspects of the problem, the team dynamics and communication shortcomings that led to such an event happening in an environment where extensive analysis is performed in support of human space flight will also be examined. Finally, the technical solution will be presented, which required a multidisciplinary effort between the U.S. and Russian control system engineers and loads and dynamics structural engineers to

  15. Process Control for Precipitation Prevention in Space Water Recovery Systems

    Science.gov (United States)

    Sargusingh, Miriam; Callahan, Michael R.; Muirhead, Dean

    2015-01-01

    The ability to recover and purify water through physiochemical processes is crucial for realizing long-term human space missions, including both planetary habitation and space travel. Because of their robust nature, rotary distillation systems have been actively pursued by NASA as one of the technologies for water recovery from wastewater primarily comprised of human urine. A specific area of interest is the prevention of the formation of solids that could clog fluid lines and damage rotating equipment. To mitigate the formation of solids, operational constraints are in place that limits such that the concentration of key precipitating ions in the wastewater brine are below the theoretical threshold. This control in effected by limiting the amount of water recovered such that the risk of reaching the precipitation threshold is within acceptable limits. The water recovery limit is based on an empirically derived worst case wastewater composition. During the batch process, water recovery is estimated by monitoring the throughput of the system. NASA Johnson Space Center is working on means of enhancing the process controls to increase water recovery. Options include more precise prediction of the precipitation threshold. To this end, JSC is developing a means of more accurately measuring the constituent of the brine and/or wastewater. Another means would be to more accurately monitor the throughput of the system. In spring of 2015, testing will be performed to test strategies for optimizing water recovery without increasing the risk of solids formation in the brine.

  16. The TJO-OAdM robotic observatory: OpenROCS and dome control

    Science.gov (United States)

    Colomé, Josep; Francisco, Xavier; Ribas, Ignasi; Casteels, Kevin; Martín, Jonatan

    2010-07-01

    The Telescope Joan Oró at the Montsec Astronomical Observatory (TJO - OAdM) is a small-class observatory working in completely unattended control. There are key problems to solve when a robotic control is envisaged, both on hardware and software issues. We present the OpenROCS (ROCS stands for Robotic Observatory Control System), an open source platform developed for the robotic control of the TJO - OAdM and similar astronomical observatories. It is a complex software architecture, composed of several applications for hardware control, event handling, environment monitoring, target scheduling, image reduction pipeline, etc. The code is developed in Java, C++, Python and Perl. The software infrastructure used is based on the Internet Communications Engine (Ice), an object-oriented middleware that provides object-oriented remote procedure call, grid computing, and publish/subscribe functionality. We also describe the subsystem in charge of the dome control: several hardware and software elements developed to specially protect the system at this identified single point of failure. It integrates a redundant control and a rain detector signal for alarm triggering and it responds autonomously in case communication with any of the control elements is lost (watchdog functionality). The self-developed control software suite (OpenROCS) and dome control system have proven to be highly reliable.

  17. Truss Climbing Robot for Space Station: Design, Analysis, and Motion Control

    Science.gov (United States)

    Chung, Wing Kwong

    The application of space robots has become more popular in performing tasks such as Intra and Extra Vehicular Activities (EVA) in Low Earth Orbit. For EVA, space robots were always designed as a chain-like manipulator with a joint configuration similar to on the earth robotic arm. Based on their joint configuration, they can be classified into two main categories. The first one is the six degrees of freedom (DOF) robotic arm including Shuttle Remote Manipulator System (SRMS), Engineering Test Satellite No. 7 (ETS-VII), the Main Arm (MA) and the Small Fine Arm (SFA) of Module Remote Manipulator System (JEMRMS). The other group is the seven-DOF space robotic arm which includes European Robotic Arm (ERA) and Space Station Remote Manipulator System (SSRMS), or Canadarm2. They not only perform manipulation tasks, but also be able to navigate on the exterior of the International Space Station (ISS). In a free floating environment, motions of a space robotic arm cause the attitude change of a space station because of their dynamic coupling effect. Hence, the stabilization of the space station attitude is important to maintain the electrical energy generated by the solar panels and the signal strength for communication. Most of research in this area focuses on the motion control of a space manipulator through the study of Generalized Jacobian Matrix. Little research has been conducted specifically on the design of locomotion mechanism of a space manipulator. This dissertation proposes a novel methodology for the locomotion on a space station which aims to lower the disturbance on a space station. Without modifying the joint configuration of conventional space manipulators, the use of a new gripping mechanism is proposed which combines the advantages of active wheels and conventional grippers. To realize the proposed gripping mechanism, this dissertation also presents the design of a novel frame climbing robot (Frambot) which is equipped with the new gripping mechanism

  18. Digital flight control software design requirements. [for space shuttle orbiter

    Science.gov (United States)

    1973-01-01

    The objective of the integrated digital flight control system is to provide rotational and translational control of the space shuttle orbiter in all phases of flight: from launch ascent through orbit to entry and touchdown, and during powered horizontal flights. The program provides a versatile control system structure while maintaining uniform communications with other programs, sensors, and control effects by using an executive routine/function subroutine format. The program reads all external variables at a single point, copies them into its dedicated storage, and then calls the required subroutines in the proper sequence. As a result, the flight control program is largely independent of other programs in the GN and C computer complex and is equally insensitive to the characteristics of the processor configuration. The integrated structure of the control system and the DFCS executive routine which embodies that structure are described. The specific estimation and control algorithms used in the various mission phases are shown. Attitude maneuver routines that interface with the DFCS are also described.

  19. Camera-Based Control for Industrial Robots Using OpenCV Libraries

    Science.gov (United States)

    Seidel, Patrick A.; Böhnke, Kay

    This paper describes a control system for industrial robots whose reactions base on the analysis of images provided by a camera mounted on top of the robot. We show that such control system can be designed and implemented with an open source image processing library and cheap hardware. Using one specific robot as an example, we demonstrate the structure of a possible control algorithm running on a PC and its interaction with the robot.

  20. Using VAPEPS for noise control on Space Station Freedom

    Science.gov (United States)

    Badilla, Gloria; Bergen, Thomas; Scharton, Terry

    1991-01-01

    Noise environmental control is an important design consideration for Space Station Freedom (SSF), both for crew safety and productivity. Acoustic noise requirements are established to eliminate fatigue and potential hearing loss by crew members from long-term exposure and to facilitate speech communication. VAPEPS (VibroAcoustic Payload Environment Prediction System) is currently being applied to SSF for prediction of the on-orbit noise and vibration environments induced in the 50 to 10,000 Hz frequency range. Various sources such as fans, pumps, centrifuges, exercise equipment, and other mechanical devices are used in the analysis. The predictions will be used in design tradeoff studies and to provide confidence that requirements will be met. Preliminary predictions show that the required levels will be exceeded unless substantial noise control measures are incorporated in the SSF design. Predicted levels for an SSF design without acoustic control treatments exceed requirements by 25 dB in some one-third octave frequency bands.

  1. Controller Design for Direct Torque Controlled Space Vector Modulated (DTC-SVM) Induction Motor Drives

    DEFF Research Database (Denmark)

    Zelechowski, M.; Kazmierkowski, M.P.; Blaabjerg, Frede

    2005-01-01

    In this paper two different methods of PI controllers for direct torque controlled-space vector modulated induction motor drives have been studied. The first one is simple method based only on symmetric optimum criterion. The second approach takes into account the full model of induction motor in...

  2. Formation control of multiple Euler-Lagrange systems via null-space-based behavioral control

    NARCIS (Netherlands)

    Chen, Jie; Huang, Jie; Dou, Lihua; Fang, Hao

    2016-01-01

    This paper addresses the formation control problem of multiple Euler-Lagrange systems with model uncertainties in the environment containing obstacles. Utilizing the null-space-based (NSB) behavioral control architecture, the proposed problem can be decomposed into elementary missions (behaviors) wi

  3. A novel mechanism controls anther opening and closing in Paris polyphylla var. Yunnanensis

    Institute of Scientific and Technical Information of China (English)

    WANG DingKang; SUN GuiFang; WANG LiFang; ZHAI ShuHua; CEN XiaoJiang

    2009-01-01

    a School of Information Science and Engineering, Yunnan University, Kunming 650091, China The phenomena of anther opening and closing in Paris polyphylla var. yunnanensis (Franch)Hand.-Mazz were described in detail, and the effects of ecological factors on those phenomena related to anther opening, closing and the fly-pollination mechanism were discussed. Anthers of P. polyphylla var. yunnanensls open in the morning and close in the evening every day during an over 20 days' pe-riod of anthesis. Light was detected as the main factor controlling this daily anther opening and closing.Anther opening can be reversed in response to rain and re-opens when rain stops. Relative humidity (RH) has a slight effect on anther opening and closing. Flower spans can be prolonged under labora-tory conditions. This novel behavior of anther is likely to be a mechanism to enhance the male fitness in this species, of which has no inherited structure to protect pollen from the perianth.

  4. Note: Tormenta: An open source Python-powered control software for camera based optical microscopy

    Science.gov (United States)

    Barabas, Federico M.; Masullo, Luciano A.; Stefani, Fernando D.

    2016-12-01

    Until recently, PC control and synchronization of scientific instruments was only possible through closed-source expensive frameworks like National Instruments' LabVIEW. Nowadays, efficient cost-free alternatives are available in the context of a continuously growing community of open-source software developers. Here, we report on Tormenta, a modular open-source software for the control of camera-based optical microscopes. Tormenta is built on Python, works on multiple operating systems, and includes some key features for fluorescence nanoscopy based on single molecule localization.

  5. Open DeveloperSpace: An Enabling Infrastructure for Stakeholders to Generate New Access Solutions.

    Science.gov (United States)

    Vanderheiden, Gregg; Riedel, Till; Peissner, Matthias; Clark, Colin; Peinado, Ignacio; Atkins, Tony; Tsakou, Gianna; Basman, Antranig; Bates, Simon; Gill, Avtar

    2017-01-01

    The DeveloperSpace, one of the core components of GPII, is a self-sustainable infrastructure and collaborative environment, where developers, implementers, consumers, prosumers and other directly and indirectly involved actors (e.g. teachers, caregivers, clinicians) may interact with and play a role in its viability and the development of new access solutions.

  6. A new open-source Python-based Space Weather data access, visualization, and analysis toolkit

    Science.gov (United States)

    de Larquier, S.; Ribeiro, A.; Frissell, N. A.; Spaleta, J.; Kunduri, B.; Thomas, E. G.; Ruohoniemi, J.; Baker, J. B.

    2013-12-01

    Space weather research relies heavily on combining and comparing data from multiple observational platforms. Current frameworks exist to aggregate some of the data sources, most based on file downloads via web or ftp interfaces. Empirical models are mostly fortran based and lack interfaces with more useful scripting languages. In an effort to improve data and model access, the SuperDARN community has been developing a Python-based Space Science Data Visualization Toolkit (DaViTpy). At the center of this development was a redesign of how our data (from 30 years of SuperDARN radars) was made available. Several access solutions are now wrapped into one convenient Python interface which probes local directories, a new remote NoSQL database, and an FTP server to retrieve the requested data based on availability. Motivated by the efficiency of this interface and the inherent need for data from multiple instruments, we implemented similar modules for other space science datasets (POES, OMNI, Kp, AE...), and also included fundamental empirical models with Python interfaces to enhance data analysis (IRI, HWM, MSIS...). All these modules and more are gathered in a single convenient toolkit, which is collaboratively developed and distributed using Github and continues to grow. While still in its early stages, we expect this toolkit will facilitate multi-instrument space weather research and improve scientific productivity.

  7. Task-Space Iterative Learning for Redundant Robotic Systems: Existence of a Task-Space Control and Convergence of Learning

    Science.gov (United States)

    Arimoto, Suguru; Sekimoto, Masahiro; Kawamura, Sadao

    This paper presents a feasibility study of iterative learning control for a class of redundant multi-joint robotic systems when a desired motion trajectory is specified in task-space with less dimension than that of joint space. First, it is shown that if the desired trajectory described in task-space for a time interval t ∈ [0,T] is twice continuously differentiable then a unique control signal describable in task-space exists despite of the system joint-redundancy. Second, a learning control update law is constructed through transpose of the Jacobian matrix of task-space coordinates with respect to joint coordinates by using measured data of motion trajectories in task-space. Third, the convergence of trajectory trackings through iterative learning is proved theoretically on the basis of original nonlinear robot dynamics in joint space.

  8. ÁREAS VERDES URBANAS, ESPAÇOS LIVRES PARA O LAZER / Urban green areas, open spaces for leisure

    Directory of Open Access Journals (Sweden)

    Kátia MAZZEI Mazzei

    2007-06-01

    Full Text Available The creation and the management of Conservation Units in urban areas, as in the category ofintegral protection as of sustainable use, aims to improve the quality of life of the urban citizenat the same time that it promotes an improvement in the urban environment quality, endowingthe urban space with vegetal covering and fundamental green areas to the reproduction of thenatural cycle and maintenance of the dynamic balance. In the urban environment, the differentcategories of open spaces and the indexes of green area per inhabitant intend to offer optionsto the leisure and recreation activities, besides of characterizing as strategic instruments forthe municipal planning, integrating the characteristics and the limits of the environment to theurban expansion.

  9. Cell Culture in Microgravity: Opening the Door to Space Cell Biology

    Science.gov (United States)

    Pellis, Neal R.; Dawson, David L. (Technical Monitor)

    1999-01-01

    Adaptational response of human cell populations to microgravity is investigated using simulation, short-term Shuttle experiments, and long-term microgravity. Simulation consists of a clinostatically-rotated cell culture system. The system is a horizontally-rotated cylinder completely filled with culture medium. Low speed rotation results in continuous-fall of the cells through the fluid medium. In this setting, cells: 1) aggregate, 2) propagate in three dimensions, 3) synthesize matrix, 4) differentiate, and 5) form sinusoids that facilitate mass transfer. Space cell culture is conducted in flight bioreactors and in static incubators. Cells grown in microgravity are: bovine cartilage, promyelocytic leukemia, kidney proximal tubule cells, adrenal medulla, breast and colon cancer, and endothelium. Cells were cultured in space to test specific hypotheses. Cartilage cells were used to determine structural differences in cartilage grown in space compared to ground-based bioreactors. Results from a 130-day experiment on Mir revealed that cartilage grown in space was substantially more compressible due to insufficient glycosaminoglycan in the matrix. Interestingly, earth-grown cartilage conformed better to the dimensions of the scaffolding material, while the Mir specimens were spherical. The other cell populations are currently being analyzed for cell surface properties, gene expression, and differentiation. Results suggest that some cells spontaneously differentiate in microgravity. Additionally, vast changes in gene expression may occur in response to microgravity. In conclusion, the transition to microgravity may constitute a physical perturbation in cells resulting in unique gene expressions, the consequences of which may be useful in tissue engineering, disease modeling, and space cell biology.

  10. Cell Culture in Microgravity: Opening the Door to Space Cell Biology

    Science.gov (United States)

    Pellis, Neal R.; Dawson, David L. (Technical Monitor)

    1999-01-01

    Adaptational response of human cell populations to microgravity is investigated using simulation, short-term Shuttle experiments, and long-term microgravity. Simulation consists of a clinostatically-rotated cell culture system. The system is a horizontally-rotated cylinder completely filled with culture medium. Low speed rotation results in continuous-fall of the cells through the fluid medium. In this setting, cells: 1) aggregate, 2) propagate in three dimensions, 3) synthesize matrix, 4) differentiate, and 5) form sinusoids that facilitate mass transfer. Space cell culture is conducted in flight bioreactors and in static incubators. Cells grown in microgravity are: bovine cartilage, promyelocytic leukemia, kidney proximal tubule cells, adrenal medulla, breast and colon cancer, and endothelium. Cells were cultured in space to test specific hypotheses. Cartilage cells were used to determine structural differences in cartilage grown in space compared to ground-based bioreactors. Results from a 130-day experiment on Mir revealed that cartilage grown in space was substantially more compressible due to insufficient glycosaminoglycan in the matrix. Interestingly, earth-grown cartilage conformed better to the dimensions of the scaffolding material, while the Mir specimens were spherical. The other cell populations are currently being analyzed for cell surface properties, gene expression, and differentiation. Results suggest that some cells spontaneously differentiate in microgravity. Additionally, vast changes in gene expression may occur in response to microgravity. In conclusion, the transition to microgravity may constitute a physical perturbation in cells resulting in unique gene expressions, the consequences of which may be useful in tissue engineering, disease modeling, and space cell biology.

  11. An optimal open/closed-loop control method with application to a pre-stressed thin duralumin plate

    Science.gov (United States)

    Nadimpalli, Sruthi Raju

    The excessive vibrations of a pre-stressed duralumin plate, suppressed by a combination of open-loop and closed-loop controls, also known as open/closed-loop control, is studied in this thesis. The two primary steps involved in this process are: Step (I) with an assumption that the closed-loop control law is proportional, obtain the optimal open-loop control by direct minimization of the performance measure consisting of energy at terminal time and a penalty on open-loop control force via calculus of variations. If the performance measure also involves a penalty on closed-loop control effort then a Fourier based method is utilized. Step (II) the energy at terminal time is minimized numerically to obtain optimal values of feedback gains. The optimal closed-loop control gains obtained are used to describe the displacement and the velocity of open-loop, closed-loop and open/closed-loop controlled duralumin plate.

  12. Approximation of reachable sets for coherently controlled open quantum systems: Application to quantum state engineering

    Science.gov (United States)

    Li, Jun; Lu, Dawei; Luo, Zhihuang; Laflamme, Raymond; Peng, Xinhua; Du, Jiangfeng

    2016-07-01

    Precisely characterizing and controlling realistic quantum systems under noises is a challenging frontier in quantum sciences and technologies. In developing reliable controls for open quantum systems, one is often confronted with the problem of the lack of knowledge on the system controllability. The purpose of this paper is to give a numerical approach to this problem, that is, to approximately compute the reachable set of states for coherently controlled quantum Markovian systems. The approximation consists of setting both upper and lower bounds for system's reachable region of states. Furthermore, we apply our reachability analysis to the control of the relaxation dynamics of a two-qubit nuclear magnetic resonance spin system. We implement some experimental tasks of quantum state engineering in this open system at a near optimal performance in view of purity: e.g., increasing polarization and preparing pseudopure states. These results demonstrate the usefulness of our theory and show interesting and promising applications of environment-assisted quantum dynamics.

  13. Open-phase operating modes of power flow control topologies in a Smart Grid Distribution Network

    Science.gov (United States)

    Astashev, M. G.; Novikov, M. A.; Panfilov, D. I.; Rashitov, P. A.; Remizevich, T. V.; Fedorova, M. I.

    2015-12-01

    The power flow regulating circuit node in an alternating current system is reviewed. The circuit node is accomplished based on a thyristor controlled phase angle regulator (TCPAR) with controlled thyristor switch. Research results of the individual phase control of the output voltage for the TCPAR are presented. Analytical expressions for the overvoltage factor calculation in the thyristor switch circuit for open-phase operating modes are received. Based on evaluation of overvoltage in operational and emergency modes, the implementability conditions of the individual phase control of the output voltage are determined. Under these conditions, maximal performance and complete controllability are provided.

  14. Active control of counter-rotating open rotor interior noise in a Dornier 728 experimental aircraft

    Science.gov (United States)

    Haase, Thomas; Unruh, Oliver; Algermissen, Stephan; Pohl, Martin

    2016-08-01

    The fuel consumption of future civil aircraft needs to be reduced because of the CO2 restrictions declared by the European Union. A consequent lightweight design and a new engine concept called counter-rotating open rotor are seen as key technologies in the attempt to reach this ambitious goals. Bearing in mind that counter-rotating open rotor engines emit very high sound pressures at low frequencies and that lightweight structures have a poor transmission loss in the lower frequency range, these key technologies raise new questions in regard to acoustic passenger comfort. One of the promising solutions for the reduction of sound pressure levels inside the aircraft cabin are active sound and vibration systems. So far, active concepts have rarely been investigated for a counter-rotating open rotor pressure excitation on complex airframe structures. Hence, the state of the art is augmented by the preliminary study presented in this paper. The study shows how an active vibration control system can influence the sound transmission of counter-rotating open rotor noise through a complex airframe structure into the cabin. Furthermore, open questions on the way towards the realisation of an active control system are addressed. In this phase, an active feedforward control system is investigated in a fully equipped Dornier 728 experimental prototype aircraft. In particular, the sound transmission through the airframe, the coupling of classical actuators (inertial and piezoelectric patch actuators) into the structure and the performance of the active vibration control system with different error sensors are investigated. It can be shown that the active control system achieves a reduction up to 5 dB at several counter-rotating open rotor frequencies but also that a better performance could be achieved through further optimisations.

  15. TCP-Call Admission Control Interaction in Multiplatform Space Architectures

    Directory of Open Access Journals (Sweden)

    Georgios Theodoridis

    2007-06-01

    Full Text Available The implementation of efficient call admission control (CAC algorithms is useful to prevent congestion and guarantee target quality of service (QoS. When TCP protocol is adopted, some inefficiencies can arise due to the peculiar evolution of the congestion window. The development of cross-layer techniques can greatly help to improve efficiency and flexibility for wireless networks. In this frame, the present paper addresses the introduction of TCP feedback into the CAC procedures in different nonterrestrial wireless architectures. CAC performance improvement is shown for different space-based architectures, including both satellites and high altitude platform (HAP systems.

  16. Optimal control of open quantum systems: a combined surrogate hamiltonian optimal control theory approach applied to photochemistry on surfaces.

    Science.gov (United States)

    Asplund, Erik; Klüner, Thorsten

    2012-03-28

    In this paper, control of open quantum systems with emphasis on the control of surface photochemical reactions is presented. A quantum system in a condensed phase undergoes strong dissipative processes. From a theoretical viewpoint, it is important to model such processes in a rigorous way. In this work, the description of open quantum systems is realized within the surrogate hamiltonian approach [R. Baer and R. Kosloff, J. Chem. Phys. 106, 8862 (1997)]. An efficient and accurate method to find control fields is optimal control theory (OCT) [W. Zhu, J. Botina, and H. Rabitz, J. Chem. Phys. 108, 1953 (1998); Y. Ohtsuki, G. Turinici, and H. Rabitz, J. Chem. Phys. 120, 5509 (2004)]. To gain control of open quantum systems, the surrogate hamiltonian approach and OCT, with time-dependent targets, are combined. Three open quantum systems are investigated by the combined method, a harmonic oscillator immersed in an ohmic bath, CO adsorbed on a platinum surface, and NO adsorbed on a nickel oxide surface. Throughout this paper, atomic units, i.e., ℏ = m(e) = e = a(0) = 1, have been used unless otherwise stated.

  17. Open Architecture Standard for NASA's Software-Defined Space Telecommunications Radio Systems

    Science.gov (United States)

    Reinhart, Richard C.; Johnson, Sandra K.; Kacpura, Thomas J.; Hall, Charles S.; Smith, Carl R.; Liebetreu, John

    2008-01-01

    NASA is developing an architecture standard for software-defined radios used in space- and ground-based platforms to enable commonality among radio developments to enhance capability and services while reducing mission and programmatic risk. Transceivers (or transponders) with functionality primarily defined in software (e.g., firmware) have the ability to change their functional behavior through software alone. This radio architecture standard offers value by employing common waveform software interfaces, method of instantiation, operation, and testing among different compliant hardware and software products. These common interfaces within the architecture abstract application software from the underlying hardware to enable technology insertion independently at either the software or hardware layer. This paper presents the initial Space Telecommunications Radio System (STRS) Architecture for NASA missions to provide the desired software abstraction and flexibility while minimizing the resources necessary to support the architecture.

  18. Opening My Voice, Claiming My Space: Theorizing the Possibilities of Postcolonial Approaches to Autoethnography

    Directory of Open Access Journals (Sweden)

    Archana A. Pathak

    2010-01-01

    Full Text Available This essay examines the ways in which postcoloniality and autoethnography can be integrated to create a space of scholarly inquiry that disrupts the colonialist enterprise prevalent in the academy. By utilizing González's four ethics of postcolonial ethnography, this essay presents an ethics for postcolonial autoethnography as a mode to build a body of scholarly research that disrupts scientific imperialism.

  19. Pylogeny: an open-source Python framework for phylogenetic tree reconstruction and search space heuristics

    Directory of Open Access Journals (Sweden)

    Alexander Safatli

    2015-06-01

    Full Text Available Summary. Pylogeny is a cross-platform library for the Python programming language that provides an object-oriented application programming interface for phylogenetic heuristic searches. Its primary function is to permit both heuristic search and analysis of the phylogenetic tree search space, as well as to enable the design of novel algorithms to search this space. To this end, the framework supports the structural manipulation of phylogenetic trees, in particular using rearrangement operators such as NNI, SPR, and TBR, the scoring of trees using parsimony and likelihood methods, the construction of a tree search space graph, and the programmatic execution of a few existing heuristic programs. The library supports a range of common phylogenetic file formats and can be used for both nucleotide and protein data. Furthermore, it is also capable of supporting GPU likelihood calculation on nucleotide character data through the BEAGLE library.Availability. Existing development and source code is available for contribution and for download by the public from GitHub (http://github.com/AlexSafatli/Pylogeny. A stable release of this framework is available for download through PyPi (Python Package Index at http://pypi.python.org/pypi/pylogeny.

  20. Research on Open-Closed-Loop Iterative Learning Control with Variable Forgetting Factor of Mobile Robots

    Directory of Open Access Journals (Sweden)

    Hongbin Wang

    2016-01-01

    Full Text Available We propose an iterative learning control algorithm (ILC that is developed using a variable forgetting factor to control a mobile robot. The proposed algorithm can be categorized as an open-closed-loop iterative learning control, which produces control instructions by using both previous and current data. However, introducing a variable forgetting factor can weaken the former control output and its variance in the control law while strengthening the robustness of the iterative learning control. If it is applied to the mobile robot, this will reduce position errors in robot trajectory tracking control effectively. In this work, we show that the proposed algorithm guarantees tracking error bound convergence to a small neighborhood of the origin under the condition of state disturbances, output measurement noises, and fluctuation of system dynamics. By using simulation, we demonstrate that the controller is effective in realizing the prefect tracking.

  1. Open access, readership, citations: a randomized controlled trial of scientific journal publishing.

    Science.gov (United States)

    Davis, Philip M

    2011-07-01

    Does free access to journal articles result in greater diffusion of scientific knowledge? Using a randomized controlled trial of open access publishing, involving 36 participating journals in the sciences, social sciences, and humanities, we report on the effects of free access on article downloads and citations. Articles placed in the open access condition (n=712) received significantly more downloads and reached a broader audience within the first year, yet were cited no more frequently, nor earlier, than subscription-access control articles (n=2533) within 3 yr. These results may be explained by social stratification, a process that concentrates scientific authors at a small number of elite research universities with excellent access to the scientific literature. The real beneficiaries of open access publishing may not be the research community but communities of practice that consume, but rarely contribute to, the corpus of literature.

  2. Ground controlled robotic assembly operations for Space Station Freedom

    Science.gov (United States)

    Parrish, Joseph C.

    1991-01-01

    A number of dextrous robotic systems and associated positioning and transportation devices are available on Space Station Freedom (SSF) to perform assembly tasks that would otherwise need to be performed by extravehicular activity (EVA) crewmembers. The currently planned operating mode for these robotic systems during the assembly phase is teleoperation by intravehicular activity (IVA) crewmembers. While this operating mode is less hazardous and expensive than manned EVA operations, and has insignificant control loop time delays, the amount of IVA time available to support telerobotic operations is much less than the anticipated requirements. Some alternative is needed to allow the robotic systems to perform useful tasks without exhausting the available IVA resources; ground control is one such alternative. The issues associated with ground control of SSF robotic systems to alleviate onboard crew time availability constraints are investigated. Key technical issues include the effect of communication time delays, the need for safe, reliable execution of remote operations, and required modifications to the SSF ground and flight system architecture. Time delay compensation techniques such as predictive displays and world model-based force reflection are addressed and collision detection and avoidance strategies to ensure the safety of the on-orbit crew, Orbiter, and SSF are described. Although more time consuming and difficult than IVA controlled teleoperations or manned EVA, ground controlled telerobotic operations offer significant benefits during the SSF assembly phase, and should be considered in assembly planning activities.

  3. Space Shuttle Orbiter entry guidance and control system sensitivity analysis

    Science.gov (United States)

    Stone, H. W.; Powell, R. W.

    1976-01-01

    An approach has been developed to determine the guidance and control system sensitivity to off-nominal aerodynamics for the Space Shuttle Orbiter during entry. This approach, which uses a nonlinear six-degree-of-freedom interactive, digital simulation, has been applied to both the longitudinal and lateral-directional axes for a portion of the orbiter entry. Boundary values for each of the aerodynamic parameters have been identified, the key parameters have been determined, and system modifications that will increase system tolerance to off-nominal aerodynamics have been recommended. The simulations were judged by specified criteria and the performance was evaluated by use of key dependent variables. The analysis is now being expanded to include the latest shuttle guidance and control systems throughout the entry speed range.

  4. Space Station CMIF extended duration metabolic control test

    Science.gov (United States)

    Schunk, Richard G.; Bagdigian, Robert M.; Carrasquillo, Robyn L.; Ogle, Kathryn Y.; Wieland, Paul O.

    1989-01-01

    The Space Station Extended Duration Metabolic Control Test (EMCT) was conducted at the MSFC Core Module Integration Facility. The primary objective of the EMCT was to gather performance data from a partially-closed regenerative Environmental Control and Life Support (ECLS) system functioning under steady-state conditions. Included is a description of the EMCT configuration, a summary of events, a discussion of anomalies that occurred during the test, and detailed results and analysis from individual measurements of water and gas samples taken during the test. A comparison of the physical, chemical, and microbiological methods used in the post test laboratory analyses of the water samples is included. The preprototype ECLS hardware used in the test, providing an overall process description and theory of operation for each hardware item. Analytical results pertaining to a system level mass balance and selected system power estimates are also included.

  5. Planar reorientation maneuvers of space multibody systems using internal controls

    Science.gov (United States)

    Reyhanoglu, Mahmut; Mcclamroch, N. H.

    1992-01-01

    In this paper a reorientation maneuvering strategy for an interconnection of planar rigid bodies in space is developed. It is assumed that there are no exogeneous torques, and torques generated by joint motors are used as means of control so that the total angular momentum of the multibody system is a constant, assumed to be zero in this paper. The maneuver strategy uses the nonintegrability of the expression for the angular momentum. We demonstrate that large-angle maneuvers can be designed to achieve an arbitrary reorientation of the multibody system with respect to an inertial frame. The theoretical background for carrying out the required maneuvers is briefly summarized. Specifications and computer simulations of a specific reorientation maneuver, and the corresponding control strategies, are described.

  6. Individual dynamic lighting control in a daylit space

    DEFF Research Database (Denmark)

    Logadóttir, Asta; Christoffersen, Jens

    2008-01-01

    in combination with daylight. Subjects performed office work for one day in a simulated office environment. Every 30 minutes the subjects were invited to use the dimmer controls to change the lighting conditions to their preferred level. Measurements were made of illuminance, luminance, CCT and energy use......The objectives of the study are to observe individual preferences for dynamic lighting, individual control and possibly achieve energy savings in a daylit space. The dynamics in this study are modifications of light level and correlated colour temperature (CCT) from the electric lighting system......, whereas questionnaires were used to evaluate user satisfaction. The study shows that subjects tended to choose a preferred CCT level, which they maintained to some extent during the day; the subjects did not regulate according to a fixed light level throughout the day. Energy savings were not accomplished...

  7. a Spatial Analysis on Gis-Hedonic Pricing Model on the Influence of Public Open Space and House Price in Klang Valley, Malaysia

    Science.gov (United States)

    Zainora, A. M.; Norzailawati, M. N.; Tuminah, P.

    2016-06-01

    Presently, it is noticeable that there is a significant influence of public open space about house price, especially in many developed nations. Literature suggests the relationship between the two aspects give impact on the housing market, however not many studies undertaken in Malaysia. Thus, this research was initiated to analyse the relationship of open space and house price via the techniques of GIS-Hedonic Pricing Model. In this regards, the GIS tool indicates the pattern of the relationship between open space and house price spatially. Meanwhile, Hedonic Pricing Model demonstrates the index of the selected criteria in determining the housing price. This research is a perceptual study of 200 respondents who were the house owners of double-storey terrace houses in four townships, namely Bandar Baru Bangi, Taman Melawati, Subang Jaya and Shah Alam, in Klang Valley. The key research question is whether the relationship between open space and house price exists and the nature of its pattern and intensity. The findings indicate that there is a positive correlation between open space and house price. Correlation analysis reveals that a weak relationship (rs research has achieved its research aims and thus, offers the value added in applying the GIS-Hedonic pricing model in analysing the influence of open space to the house price in the form of spatially and textually.

  8. Adaptive Controller for Compact Fourier Transform Spectrometer with Space Applications

    Science.gov (United States)

    Keymeulen, D.; Yiu, P.; Berisford, D. F.; Hand, K. P.; Carlson, R. W.; Conroy, M.

    2014-12-01

    Here we present noise mitigation techniques developed as part of an adaptive controller for a very compact Compositional InfraRed Interferometric Spectrometer (CIRIS) implemented on a stand-alone field programmable gate array (FPGA) architecture with emphasis on space applications in high radiation environments such as Europa. CIRIS is a novel take on traditional Fourier Transform Spectrometers (FTS) and replaces linearly moving mirrors (characteristic of Michelson interferometers) with a constant-velocity rotating refractor to variably phase shift and alter the path length of incoming light. The design eschews a monochromatic reference laser typically used for sampling clock generation and instead utilizes constant time-sampling via internally generated clocks. This allows for a compact and robust device, making it ideal for spaceborne measurements in the near-IR to thermal-IR band (2-12 µm) on planetary exploration missions. The instrument's embedded microcontroller is implemented on a VIRTEX-5 FPGA and a PowerPC with the aim of sampling the instrument's detector and optical rotary encoder in order to construct interferograms. Subsequent onboard signal processing provides spectral immunity from the noise effects introduced by the compact design's removal of a reference laser and by the radiation encountered during space flight to destinations such as Europa. A variety of signal processing techniques including resampling, radiation peak removal, Fast Fourier Transform (FFT), spectral feature alignment, dispersion correction and calibration processes are applied to compose the sample spectrum in real-time with signal-to-noise-ratio (SNR) performance comparable to laser-based FTS designs in radiation-free environments. The instrument's FPGA controller is demonstrated with the FTS to characterize its noise mitigation techniques and highlight its suitability for implementation in space systems.

  9. Controlled Release of Agrochemicals Intercalated into Montmorillonite Interlayer Space

    Directory of Open Access Journals (Sweden)

    Harrison Wanyika

    2014-01-01

    Full Text Available Periodic application of agrochemicals has led to high cost of production and serious environmental pollution. In this study, the ability of montmorillonite (MMT clay to act as a controlled release carrier for model agrochemical molecules has been investigated. Urea was loaded into MMT by a simple immersion technique while loading of metalaxyl was achieved by a rotary evaporation method. The successful incorporation of the agrochemicals into the interlayer space of MMT was confirmed by several techniques, such as, significant expansion of the interlayer space, reduction of Barrett-Joyner-Halenda (BJH pore volumes and Brunauer-Emmett-Teller (BET surface areas, and appearance of urea and metalaxyl characteristic bands on the Fourier-transform infrared spectra of the urea loaded montmorillonite (UMMT and metalaxyl loaded montmorillonite (RMMT complexes. Controlled release of the trapped molecules from the matrix was done in water and in the soil. The results reveal slow and sustained release behaviour for UMMT for a period of 10 days in soil. For a period of 30 days, MMT delayed the release of metalaxyl in soil by more than 6 times. It is evident that MMT could be used to improve the efficiency of urea and metalaxyl delivery in the soil.

  10. Controlled Release of Agrochemicals Intercalated into Montmorillonite Interlayer Space

    Science.gov (United States)

    2014-01-01

    Periodic application of agrochemicals has led to high cost of production and serious environmental pollution. In this study, the ability of montmorillonite (MMT) clay to act as a controlled release carrier for model agrochemical molecules has been investigated. Urea was loaded into MMT by a simple immersion technique while loading of metalaxyl was achieved by a rotary evaporation method. The successful incorporation of the agrochemicals into the interlayer space of MMT was confirmed by several techniques, such as, significant expansion of the interlayer space, reduction of Barrett-Joyner-Halenda (BJH) pore volumes and Brunauer-Emmett-Teller (BET) surface areas, and appearance of urea and metalaxyl characteristic bands on the Fourier-transform infrared spectra of the urea loaded montmorillonite (UMMT) and metalaxyl loaded montmorillonite (RMMT) complexes. Controlled release of the trapped molecules from the matrix was done in water and in the soil. The results reveal slow and sustained release behaviour for UMMT for a period of 10 days in soil. For a period of 30 days, MMT delayed the release of metalaxyl in soil by more than 6 times. It is evident that MMT could be used to improve the efficiency of urea and metalaxyl delivery in the soil. PMID:24696655

  11. Linux-based Platform for Open Architecture Controller and Its Modular Developing Method

    Institute of Scientific and Technical Information of China (English)

    迟永琳; 王宇晗; 吴祖育; 蔡建国

    2003-01-01

    Linux-based Platform for Open Architecture Controller ( POAC ), a new open architecture controller and its modular developing method are discussed. POAC divides the application software of controller into the developing system and the application system. In the developing system, PAOC abstracts a series of function modules with unified data interface and function interface. In the application system, POAC defines the model of the architecture module, realizing the interoperability and interchangeability between the architecture modules. The modular developing method entitles the users to make up an application system with some architecture modules, which consist of a set of function modules. The modular developing method decreases the developing time from the standard of controller architecture to the product.

  12. Two neural network algorithms for designing optimal terminal controllers with open final time

    Science.gov (United States)

    Plumer, Edward S.

    1992-01-01

    Multilayer neural networks, trained by the backpropagation through time algorithm (BPTT), have been used successfully as state-feedback controllers for nonlinear terminal control problems. Current BPTT techniques, however, are not able to deal systematically with open final-time situations such as minimum-time problems. Two approaches which extend BPTT to open final-time problems are presented. In the first, a neural network learns a mapping from initial-state to time-to-go. In the second, the optimal number of steps for each trial run is found using a line-search. Both methods are derived using Lagrange multiplier techniques. This theoretical framework is used to demonstrate that the derived algorithms are direct extensions of forward/backward sweep methods used in N-stage optimal control. The two algorithms are tested on a Zermelo problem and the resulting trajectories compare favorably to optimal control results.

  13. Control of open-loop neutrally stable systems subject to actuator saturation and external disturbances

    NARCIS (Netherlands)

    Wang, Xu; Saberi, Ali; Grip, H°avard Fjær; Stoorvogel, Antonie Arij

    2013-01-01

    In this paper, we study the disturbance response of open-loop neutrally stable linear systems with saturating linear feedback controller. It is shown that the closed-loop states remain bounded if the disturbances con- sists of those signals that do not have large sustained frequency components

  14. Open reduction versus endoscopically controlled reconstruction of orbital floor fractures: a retrospective analysis.

    NARCIS (Netherlands)

    Hundepool, A.C.; Willemsen, M.A.A.P.; Koudstaal, M.J.; Wal, K.G.H. van der

    2012-01-01

    The aim of this study was to compare the postoperative results of open reduction versus endoscopically controlled reconstructions of orbital floor fractures. The medical records of 83 patients, treated between January 2000 and December 2008, were reviewed for enophthalmos, diplopia and complications

  15. Open-loop quantum control as a resource for secure communications

    Science.gov (United States)

    Pastorello, Davide

    2016-05-01

    Properties of unitary time evolution of quantum systems can be applied to define quantum cryptographic protocols. Dynamics of a qubit can be exploited as a data encryption/decryption procedure by means of timed measurements, implementation of an open-loop control scheme over a qubit increases robustness of a protocol employing this principle.

  16. Open-loop quantum control as a resource for secure communications

    CERN Document Server

    Pastorello, Davide

    2015-01-01

    Properties of unitary time evolution of quantum systems can be applied to define quantum cryptographic protocols. Dynamics of a qubit can be exploited as a data encryption/decryption procedure by means of timed measurements, implementation of an open-loop control scheme over a qubit increases robustness of a protocol employing this principle.

  17. Implementing Randomised Control Trials in Open and Distance Learning: A Feasibility Study

    Science.gov (United States)

    Herodotou, Christothea; Heiser, Sarah; Rienties, Bart

    2017-01-01

    Randomised control trials (RCTs) are an evidence-based research approach which has not yet been adopted and widely used in open and distance education to inform educational policy and practice. Despite the challenges entailed in their application, RCTs hold the power to robustly evaluate the effects of educational interventions in distance…

  18. Supervised exercise therapy versus usual care for patellofemoral pain syndrome: an open label randomised controlled trial.

    NARCIS (Netherlands)

    R. van Linschoten (Robbart); M. van Middelkoop (Marienke); M.Y. Berger (Marjolein); E.M. Heintjes (Edith); J.A.N. Verhaar (Jan); S.P. Willemsen (Sten); B.W. Koes (Bart); S.M. Bierma-Zeinstra (Sita)

    2009-01-01

    textabstractOBJECTIVE: To assess the effectiveness of supervised exercise therapy compared with usual care with respect to recovery, pain, and function in patients with patellofemoral pain syndrome. DESIGN: Open label randomised controlled trial. SETTING: General practice and sport physician practic

  19. Toward an open-access global database for mapping, control, and surveillance of neglected tropical diseases

    DEFF Research Database (Denmark)

    Hürlimann, Eveline; Schur, Nadine; Boutsika, Konstantina

    2011-01-01

    for monitoring and evaluation. What is currently missing is a georeferenced global database for NTDs providing open-access to the available survey data that is constantly updated and can be utilized by researchers and disease control managers to support other relevant stakeholders. We describe the steps taken...

  20. The Model-Driven openETCS Paradigm for Secure, Safe and Certifiable Train Control Systems

    DEFF Research Database (Denmark)

    Peleska, Jan; Feuser, Johannes; Haxthausen, Anne Elisabeth

    2012-01-01

    A novel approach to managing development, verification, and validation artifacts for the European Train Control System as open, publicly available items is analyzed and discussed with respect to its implications on system safety, security, and certifiability. After introducing this so-called model...

  1. Critical Spaces for Critical Times: Global Conversations in Literacy Research as an Open Professional Development and Practices Resource

    Directory of Open Access Journals (Sweden)

    Peggy Albers

    2015-09-01

    Full Text Available This paper reflects an OER (Open Educational Resources critical literacy project, Global Conversations in Literacy Research (GCLR, (www.globalconversationsinliteracy.wordpress.com, now in its fourth year. GCLR annually hosts seven web seminars presented by internationally recognized literacy and education scholars. We outline key dimensions of GCLR not only as an OER but as an open educational practice (OEP (Andrade et al., 2011 that through its design, not only provides open access to scholarship, but also understands the critical nexus among resources, practices and theory. Informed by data from a longitudinal study, this paper situates these dimensions within professional development literature, and outlines GCLR as a critical space designed for critical times, and the importance of intentionality when accessing OER. Like scholars before us, we argue that that availability is not the only consideration when using OER (Andrade et al., 2011; OER must be considered in relation to pedagogical considerations and how OER are used as a critical component to online professional development.

  2. Multipurpose Cooling Garment for Improved Space Suit Environmental Control Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Future manned space exploration missions will require space suits with capabilities beyond the current state of the art. Portable Life Support Systems for these...

  3. Monitoring of International Space Station Telemetry Using Shewhart Control Charts

    Science.gov (United States)

    Fitch, Jeffery T.; Simon, Alan L.; Gouveia, John A.; Hillin, Andrew M.; Hernandez, Steve A.

    2012-01-01

    Shewhart control charts have been established as an expedient method for analyzing dynamic, trending data in order to identify anomalous subsystem performance as soon as such performance would exceed a statistically established baseline. Additionally, this leading indicator tool integrates a selection methodology that reduces false positive indications, optimizes true leading indicator events, minimizes computer processor unit duty cycles, and addresses human factor concerns (i.e., the potential for flight-controller data overload). This innovation leverages statistical process control, and provides a relatively simple way to allow flight controllers to focus their attention on subtle system changes that could lead to dramatic off-nominal system performance. Finally, this capability improves response time to potential hardware damage and/or crew injury, thereby improving space flight safety. Shewhart control charts require normalized data. However, the telemetry from the ISS Early External Thermal Control System (EETCS) was not normally distributed. A method for normalizing the data was implemented, as was a means of selecting data windows, the number of standard deviations (Sigma Level), the number of consecutive points out of limits (Sequence), and direction (increasing or decreasing trend data). By varying these options, and treating them like dial settings, the number of nuisance alerts and leading indicators were optimized. The goal was to capture all leading indicators while minimizing the number of nuisances. Lean Six Sigma (L6S) design of experiment methodologies were employed. To optimize the results, Perl programming language was used to automate the massive amounts of telemetry data, control chart plots, and the data analysis.

  4. Opening Up a ‘Third Space’ To Innovate Curricula

    Directory of Open Access Journals (Sweden)

    Hannelize Jacobs

    2012-01-01

    Full Text Available Problem statement: Against the background of innovating learner experiences in South African schools and higher learning institutions in the 21st century, it is crucial to determine, in the analogy to the words, ‘what holds a place together’. It is necessary to know how to create that sense of belonging, what the vision and mission are, what is valued and expected, what one can identify with and what will make educators move collectively towards taking united ownership of the future and create the next best learning and teaching practice. Approach: Appreciate inquiry, as research method for this study, searches for the identification and enhancement of the life-giving forces as it explores what should be present or need to be present in a uniquely constructed third space. Appreciative inquiry is crafted in a post-positivist tradition grounded in affirmation and appreciation. True to the vision of the creators of this method who regard it as an inquiry to uncover profound knowledge entities of human systems in order to co-construct the best and highest future of that system, this investigation focuses on uncovering past, present and future learning and teaching practices to innovate the next curricula. Conclusion/Recommendations: In this study we argue that when innovating curricula, South African educators have to elicit local pre-knowledge and experiences to shape them into a leveled playing field before they can add on global international knowledge. South African educators have to construct the next practice in learning and teaching by integrating local and global knowledge in a unique space (what Bhabha refers to as a ‘third’ space.

  5. Wave emission from heterogeneities opens a way to controlling chaos in the heart.

    Science.gov (United States)

    Pumir, A; Nikolski, V; Hörning, M; Isomura, A; Agladze, K; Yoshikawa, K; Gilmour, R; Bodenschatz, E; Krinsky, V

    2007-11-16

    The effectiveness of chaos control in large systems increases with the number of control sites. We find that electric field induced wave emission from heterogeneities (WEH) in the heart gives a unique opportunity to have as many control sites as needed. The number of pacing sites grows with the amplitude of the electric field. We demonstrate that WEH has important advantages over methods used in clinics, and opens a new way to manipulate vortices in experiments, and potentially to radically improve the clinical methods of chaos control in the heart.

  6. The Conductive Thermal Control Material Systems for Space Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This Phase II proposal is submitted to further develop and Validate materials and process engineering of the space environment stable, multifunctional conductive...

  7. Integrated Power and Attitude Control Systems for Space Station

    Science.gov (United States)

    Oglevie, R. E.; Eisenhaure, D. B.

    1985-01-01

    Integrated Power and Attitude Control Systems (IPACS) studies performed over a decade ago established the feasibility of simultaneously storing electrical energy in wheels and utilizing the resulting momentum for spacecraft attitude control. It was shown that such a system possessed many advantages over other contemporary energy storage and attitude control systems in many applications. More recent technology advances in composite rotors, magnetic bearings, and power control electronics have triggered new optimism regarding the feasibility and merits of such a system. The paper presents the results of a recent study whose focus was to define an advanced IPACS and to evaluate its merits for the Space Station application. A system and component design concept is developed to establish the system performance capability. A system level trade study, including life-cycle costing, is performed to define the merits of the system relative to two other candidate systems. It is concluded that an advanced IPACS concept is not only feasible, but offers substantial savings in mass, and life-cycle cost.

  8. Generating optimal control simulations of musculoskeletal movement using OpenSim and MATLAB.

    Science.gov (United States)

    Lee, Leng-Feng; Umberger, Brian R

    2016-01-01

    Computer modeling, simulation and optimization are powerful tools that have seen increased use in biomechanics research. Dynamic optimizations can be categorized as either data-tracking or predictive problems. The data-tracking approach has been used extensively to address human movement problems of clinical relevance. The predictive approach also holds great promise, but has seen limited use in clinical applications. Enhanced software tools would facilitate the application of predictive musculoskeletal simulations to clinically-relevant research. The open-source software OpenSim provides tools for generating tracking simulations but not predictive simulations. However, OpenSim includes an extensive application programming interface that permits extending its capabilities with scripting languages such as MATLAB. In the work presented here, we combine the computational tools provided by MATLAB with the musculoskeletal modeling capabilities of OpenSim to create a framework for generating predictive simulations of musculoskeletal movement based on direct collocation optimal control techniques. In many cases, the direct collocation approach can be used to solve optimal control problems considerably faster than traditional shooting methods. Cyclical and discrete movement problems were solved using a simple 1 degree of freedom musculoskeletal model and a model of the human lower limb, respectively. The problems could be solved in reasonable amounts of time (several seconds to 1-2 hours) using the open-source IPOPT solver. The problems could also be solved using the fmincon solver that is included with MATLAB, but the computation times were excessively long for all but the smallest of problems. The performance advantage for IPOPT was derived primarily by exploiting sparsity in the constraints Jacobian. The framework presented here provides a powerful and flexible approach for generating optimal control simulations of musculoskeletal movement using OpenSim and MATLAB. This

  9. Generating optimal control simulations of musculoskeletal movement using OpenSim and MATLAB

    Directory of Open Access Journals (Sweden)

    Leng-Feng Lee

    2016-01-01

    Full Text Available Computer modeling, simulation and optimization are powerful tools that have seen increased use in biomechanics research. Dynamic optimizations can be categorized as either data-tracking or predictive problems. The data-tracking approach has been used extensively to address human movement problems of clinical relevance. The predictive approach also holds great promise, but has seen limited use in clinical applications. Enhanced software tools would facilitate the application of predictive musculoskeletal simulations to clinically-relevant research. The open-source software OpenSim provides tools for generating tracking simulations but not predictive simulations. However, OpenSim includes an extensive application programming interface that permits extending its capabilities with scripting languages such as MATLAB. In the work presented here, we combine the computational tools provided by MATLAB with the musculoskeletal modeling capabilities of OpenSim to create a framework for generating predictive simulations of musculoskeletal movement based on direct collocation optimal control techniques. In many cases, the direct collocation approach can be used to solve optimal control problems considerably faster than traditional shooting methods. Cyclical and discrete movement problems were solved using a simple 1 degree of freedom musculoskeletal model and a model of the human lower limb, respectively. The problems could be solved in reasonable amounts of time (several seconds to 1–2 hours using the open-source IPOPT solver. The problems could also be solved using the fmincon solver that is included with MATLAB, but the computation times were excessively long for all but the smallest of problems. The performance advantage for IPOPT was derived primarily by exploiting sparsity in the constraints Jacobian. The framework presented here provides a powerful and flexible approach for generating optimal control simulations of musculoskeletal movement using

  10. Genelab: Scientific Partnerships and an Open-Access Database to Maximize Usage of Omics Data from Space Biology Experiments

    Science.gov (United States)

    Reinsch, S. S.; Galazka, J..; Berrios, D. C; Chakravarty, K.; Fogle, H.; Lai, S.; Bokyo, V.; Timucin, L. R.; Tran, P.; Skidmore, M.

    2016-01-01

    NASA's mission includes expanding our understanding of biological systems to improve life on Earth and to enable long-duration human exploration of space. The GeneLab Data System (GLDS) is NASA's premier open-access omics data platform for biological experiments. GLDS houses standards-compliant, high-throughput sequencing and other omics data from spaceflight-relevant experiments. The GeneLab project at NASA-Ames Research Center is developing the database, and also partnering with spaceflight projects through sharing or augmentation of experiment samples to expand omics analyses on precious spaceflight samples. The partnerships ensure that the maximum amount of data is garnered from spaceflight experiments and made publically available as rapidly as possible via the GLDS. GLDS Version 1.0, went online in April 2015. Software updates and new data releases occur at least quarterly. As of October 2016, the GLDS contains 80 datasets and has search and download capabilities. Version 2.0 is slated for release in September of 2017 and will have expanded, integrated search capabilities leveraging other public omics databases (NCBI GEO, PRIDE, MG-RAST). Future versions in this multi-phase project will provide a collaborative platform for omics data analysis. Data from experiments that explore the biological effects of the spaceflight environment on a wide variety of model organisms are housed in the GLDS including data from rodents, invertebrates, plants and microbes. Human datasets are currently limited to those with anonymized data (e.g., from cultured cell lines). GeneLab ensures prompt release and open access to high-throughput genomics, transcriptomics, proteomics, and metabolomics data from spaceflight and ground-based simulations of microgravity, radiation or other space environment factors. The data are meticulously curated to assure that accurate experimental and sample processing metadata are included with each data set. GLDS download volumes indicate strong

  11. Acoustic evaluation and adjustment of an open-plan office through architectural design and noise control.

    Science.gov (United States)

    Passero, Carolina Reich Marcon; Zannin, Paulo Henrique Trombetta

    2012-11-01

    Arranging office space into a single open room offers advantages in terms of easy exchange of information and interaction among coworkers, but reduces privacy and acoustic comfort. Thus, the purpose of this work was to evaluate the acoustic quality of a real open-plan office and to propose changes in the room to improve the acoustic conditioning of this office. The computational model of the office under study was calibrated based on RT and STI measurements. Predictions were made of the RT and STI, which generated the radius of distraction r(D), and the rate of spatial decay of sound pressure levels per distance doubling DL(2) in the real conditions of the office and after modifications of the room. The insertion of dividers between work stations and an increase in the ceiling's sound absorption improved the acoustic conditions in the office under study. Copyright © 2012 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  12. Space motion sickness: The sensory motor controls and cardiovascular correlation

    Science.gov (United States)

    Souvestre, Philippe A.; Blaber, Andrew P.; Landrock, Clinton K.

    Background and PurposeSpace motion sickness (SMS) and related symptoms remain a major limiting factor in Space operations. A recent comprehensive literature review [J.R. Lackner, Z. DiZio, Space motion sickness, Experimental Brain Research 175 (2006) 377-399, doi 10.1007/s00221-006-0697-y] concluded that SMS does not represent a unique diagnostic entity, and there is no adequate predictor of SMS' susceptibility and severity. No countermeasure has been found reliable to prevent or treat SMS symptoms onset. Recent neurophysiological findings on sensory-motor controls monitoring [P.A. Souvestre, C. Landrock, Biomedical-performance monitoring and assessment of astronauts by means of an ocular vestibular monitoring system, Acta Astronautica, 60 (4-7) (2007) 313-321, doi:10.1016/j.actaastro.2006.08.013] and heart-rate variability (HRV) measurements relationship could explain post-flight orthostatic intolerance (PFOI) in astronauts [A.P. Blaber, R.L. Bondar, M.S. Kassam, Heart rate variability and short duration space flight: relationship to post-flight orthostatic intolerance, BMC Physiology 4 (2004) 6]. These two methodologies are generally overlooked in SMS' analysis. In this paper we present the case for a strong relationship between sensory-motor controls related symptoms, including orthostatic intolerance (OI) and SMS symptoms. MethodsThis paper expands on several previously published papers [J.R. Lackner, Z. DiZio, Space motion sickness, Experimental Brain Research 175 (2006) 377-399, doi 10.1007/s00221-006-0697-y; P.A. Souvestre, C. Landrock, Biomedical-performance monitoring and assessment of astronauts by means of an ocular vestibular monitoring system, Acta Astronautica, 60 (4-7) (2007) 313-321, doi:10.1016/j.actaastro.2006.08.013] along with an updated literature review. An analysis of a 10-year period clinical data from trauma patients experiencing postural deficiency syndrome (PDS) show assessment and monitoring techniques which successfully identify trauma

  13. 46 CFR 32.56-55 - Control spaces-T/ALL.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Control spaces-T/ALL. 32.56-55 Section 32.56-55 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS SPECIAL EQUIPMENT, MACHINERY, AND HULL....56-55 Control spaces—T/ALL. Bulkheads and decks that separate control spaces from adjacent spaces...

  14. 46 CFR 30.10-19a - Control space-TB/ALL.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Control space-TB/ALL. 30.10-19a Section 30.10-19a Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS GENERAL PROVISIONS Definitions § 30.10-19a Control space—TB/ALL. The term control space means an enclosed space in which is located a...

  15. Vector Control of Three-Phase Induction Motor with Two Stator Phases Open-Circuit

    Directory of Open Access Journals (Sweden)

    Seyed Hesam Asgari

    2015-06-01

    Full Text Available Variable frequency drives are used to provide reliable dynamic systems and significant reduction in usage of energy and costs of the induction motors. Modeling and control of faulty or an unbalanced three-phase induction motor is obviously different from healthy three-phase induction motor. Using conventional vector control techniques such as Field-Oriented Control (FOC for faulty three-phase induction motor, results in a significant torque and speed oscillation. This research presented a novel method for vector control of three-phase induction motor under fault condition (two-phase open circuit fault. The proposed method for vector control of faulty machine is based on rotor FOC method. A comparison between conventional and modified controller shows that the modified controller has been significantly reduced the torque and speed oscillations.

  16. Nonparametric Problem-Space Clustering: Learning Efficient Codes for Cognitive Control Tasks

    Directory of Open Access Journals (Sweden)

    Domenico Maisto

    2016-02-01

    Full Text Available We present an information-theoretic method permitting one to find structure in a problem space (here, in a spatial navigation domain and cluster it in ways that are convenient to solve different classes of control problems, which include planning a path to a goal from a known or an unknown location, achieving multiple goals and exploring a novel environment. Our generative nonparametric approach, called the generative embedded Chinese restaurant process (geCRP, extends the family of Chinese restaurant process (CRP models by introducing a parameterizable notion of distance (or kernel between the states to be clustered together. By using different kernels, such as the the conditional probability or joint probability of two states, the same geCRP method clusters the environment in ways that are more sensitive to different control-related information, such as goal, sub-goal and path information. We perform a series of simulations in three scenarios—an open space, a grid world with four rooms and a maze having the same structure as the Hanoi Tower—in order to illustrate the characteristics of the different clusters (obtained using different kernels and their relative benefits for solving planning and control problems.

  17. Controller design approaches for large space structures using LQG control theory. [Linear Quadratic Gaussian

    Science.gov (United States)

    Joshi, S. M.; Groom, N. J.

    1979-01-01

    The paper presents several approaches for the design of reduced order controllers for large space structures. These approaches are shown to be based on LQG control theory and include truncation, modified truncation regulators and estimators, use of higher order estimators, selective modal suppression, and use of polynomial estimators. Further, the use of direct sensor feedback, as opposed to a state estimator, is investigated for some of these approaches. Finally, numerical results are given for a long free beam.

  18. Dynamic Control of a Space Robot System With No Thrust Jets Controlled Base

    Science.gov (United States)

    1991-08-01

    properties of the system are studied. It is found that the free-flying space robot dynamics cannot be linearly expressed in terms of dynamic parameters...control. Nearly all of these algorithms are based on the property of linwar parameterization in the robot dynamics , i.e., possibility of selecting a...proper set of equivalent parameters such that the robot dynamics depends linearly on these parameters. These controllers can take full consideration

  19. Simulation of neutron multiplicity measurements using Geant4. Open source software for nuclear arms control

    Energy Technology Data Exchange (ETDEWEB)

    Kuett, Moritz

    2016-07-07

    Nuclear arms control, including nuclear safeguards and verification technologies for nuclear disarmament typically use software as part of many different technological applications. This thesis proposes to use three open source criteria for such software, allowing users and developers to have free access to a program, have access to the full source code and be able to publish modifications for the program. This proposition is presented and analyzed in detail, together with the description of the development of ''Open Neutron Multiplicity Simulation'', an open source software tool to simulate neutron multiplicity measurements. The description includes physical background of the method, details of the developed program and a comprehensive set of validation calculations.

  20. Amphiphilic Nanoparticles Control the Growth and Stability of Lipid Bilayers with Open Edges

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Sun Hae Ra; Lee, Hee-Young; Bishop, Kyle J. M.

    2015-07-23

    Molecular amphiphiles self-assemble in polar media to form ordered structures such as micelles and vesicles essential to a broad range of industrial and biological processes. Some of these architectures such as bilayer sheets, helical ribbons, and hollow tubules are potentially useful but inherently unstable owing to the presence of open edges that expose the hydrophobic bilayer core. Here, we describe a strategy to stabilize open bilayer structures using amphiphilic nanoparticle surfactants that present mixtures of hydrophilic and hydrophobic ligands on their surface. We observe that these particles bind selectively to the open edge of bilayer membranes to stabilize otherwise transient amphiphile assemblies. We show how such particles can precisely control the size of lipid tubules, how they can inhibit the formation of undesirable assemblies such as gallstone precursors, and how they can stabilize free-floating lipid microdiscs.

  1. Space station freedom resource nodes internal thermal control system

    Science.gov (United States)

    Merhoff, Paul; Dellinger, Brent; Taggert, Shawn; Cornwell, John

    1993-01-01

    This paper presents an overview of the design and operation of the internal thermal control system (ITCS) developed for Space Station Freedom by the NASA-Johnson Space Center and McDonnell Douglas Aerospace to provide cooling for the resource nodes, airlock, and pressurized logistics modules. The ITCS collects, transports and rejects waste heat from these modules by a dual-loop, single-phase water cooling system. ITCS performance, cooling, and flow rate requirements are presented. An ITCS fluid schematic is shown and an overview of the current baseline system design and its operation is presented. Assembly sequence of the ITCS is explained as its configuration develops from Man Tended Capability (MTC), for which node 2 alone is cooled, to Permanently Manned Capability (PMC) where the airlock, a pressurized logistics module, and node 1 are cooled, in addition to node 2. A SINDA/FLUINT math model of the ITCS is described, and results of analyses for an MTC and a PMC case are shown and discussed.

  2. Preliminary design of the Space Station internal thermal control system

    Science.gov (United States)

    Herrin, Mark T.; Patterson, David W.; Turner, Larry D.

    1987-01-01

    The baseline preliminary design configuration of the Internal Thermal Control system (ITCS) of the U.S. Space Station pressurized elements (i.e., the Habitation and U.S. Laboratory modules, pressurized logistics carrier, and resources nodes) is defined. The ITCS is composed of both active and passive components. The subsystems which comprise the ITCS are identified and their functional descriptions are provided. The significant trades and analyses, which were performed during Phase B (i.e., the preliminary design phase) that resulted in the design described herein, are discussed. The ITCS interfaces with the station's central Heat Rejection and Transport System (HRTS), other systems, and externally attached pressurized payloads are described. Requirements on the ITCS with regard to redundancy and experiment support are also addressed.

  3. Multivariable control of the Space Shuttle Remote Manipulator System

    Science.gov (United States)

    Adams, Neil J.; Appleby, Brent D.; Prakash, OM, II

    1991-01-01

    Linear controllers are designed to regulate the end effector of the Space Shuttle Remote Manipulator System (SRMS) operating in position hold mode. Design techniques used include H2 and H-infinity optimization. The nonlinear SRMS is linearized by modeling the effects of the significant nonlinearities as uncertain parameters. Each regulator design is evaluated for robust stability using both the small gain theorem with an H-infinity norm and the less conservative mu-analysis test. Regulator designs offer significant improvement over the current system for the nominal plant. Unfortunately, the SRMS model suffers from lightly damped poles with real parametric uncertainty. Under such conditions, the mu-analysis test, which allows for complex perturbations, cannot guarantee robust stability.

  4. Laparoscopic versus open gastrectomy for gastric cancer, a multicenter prospectively randomized controlled trial (LOGICA-trial).

    Science.gov (United States)

    Haverkamp, Leonie; Brenkman, Hylke J F; Seesing, Maarten F J; Gisbertz, Suzanne S; van Berge Henegouwen, Mark I; Luyer, Misha D P; Nieuwenhuijzen, Grard A P; Wijnhoven, Bas P L; van Lanschot, Jan J B; de Steur, Wobbe O; Hartgrink, Henk H; Stoot, Jan H M B; Hulsewé, Karel W E; Spillenaar Bilgen, Ernst J; Rütter, Jeroen E; Kouwenhoven, Ewout A; van Det, Marc J; van der Peet, Donald L; Daams, Freek; Draaisma, Werner A; Broeders, Ivo A M J; van Stel, Henk F; Lacle, Miangela M; Ruurda, Jelle P; van Hillegersberg, Richard

    2015-07-29

    For gastric cancer patients, surgical resection with en-bloc lymphadenectomy is the cornerstone of curative treatment. Open gastrectomy has long been the preferred surgical approach worldwide. However, this procedure is associated with considerable morbidity. Several meta-analyses have shown an advantage in short-term outcomes of laparoscopic gastrectomy compared to open procedures, with similar oncologic outcomes. However, it remains unclear whether the results of these Asian studies can be extrapolated to the Western population. In this trial from the Netherlands, patients with resectable gastric cancer will be randomized to laparoscopic or open gastrectomy. The study is a non-blinded, multicenter, prospectively randomized controlled superiority trial. Patients (≥18 years) with histologically proven, surgically resectable (cT1-4a, N0-3b, M0) gastric adenocarcinoma and European Clinical Oncology Group performance status 0, 1 or 2 are eligible to participate in the study after obtaining informed consent. Patients (n = 210) will be included in one of the ten participating Dutch centers and are randomized to either laparoscopic or open gastrectomy. The primary outcome is postoperative hospital stay (days). Secondary outcome parameters include postoperative morbidity and mortality, oncologic outcomes, readmissions, quality of life and cost-effectiveness. In this randomized controlled trial laparoscopic and open gastrectomy are compared in patients with resectable gastric cancer. It is expected that laparoscopic gastrectomy will result in a faster recovery of the patient and a shorter hospital stay. Secondly, it is expected that laparoscopic gastrectomy will be associated with a lower postoperative morbidity, less readmissions, higher cost-effectiveness, better postoperative quality of life, but with similar mortality and oncologic outcomes, compared to open gastrectomy. The study started on 1 December 2014. Inclusion and follow-up will take 3 and 5

  5. Toward an open-access global database for mapping, control, and surveillance of neglected tropical diseases

    DEFF Research Database (Denmark)

    Hürlimann, Eveline; Schur, Nadine; Boutsika, Konstantina;

    2011-01-01

    After many years of general neglect, interest has grown and efforts came under way for the mapping, control, surveillance, and eventual elimination of neglected tropical diseases (NTDs). Disease risk estimates are a key feature to target control interventions, and serve as a benchmark...... for monitoring and evaluation. What is currently missing is a georeferenced global database for NTDs providing open-access to the available survey data that is constantly updated and can be utilized by researchers and disease control managers to support other relevant stakeholders. We describe the steps taken...

  6. A Survey on Open-Source Flight Control Platforms of Unmanned Aerial Vehicle

    DEFF Research Database (Denmark)

    Ebeid, Emad Samuel Malki; Skriver, Martin; Jin, Jie

    2017-01-01

    Recently, Unmanned Aerial Vehicle (UAV), so-called drones, have gotten a lot of attention in academic research and commercial applications due to their simple structure, ease of operations and low-cost hardware components. Flight controller, embedded electronics component, represents the core part...... of the drone. It aims at performing the main operations of the drone (e.g., autonomous control and navigation). There are various types of flight controllers and each of them has its own characteristics and features. This paper presents an extensive survey on the publicly available open-source flight...

  7. A SPATIAL ANALYSIS ON GIS-HEDONIC PRICING MODEL ON THE INFLUENCE OF PUBLIC OPEN SPACE AND HOUSE PRICE IN KLANG VALLEY, MALAYSIA

    Directory of Open Access Journals (Sweden)

    A. M. Zainora

    2016-06-01

    Full Text Available Presently, it is noticeable that there is a significant influence of public open space about house price, especially in many developed nations. Literature suggests the relationship between the two aspects give impact on the housing market, however not many studies undertaken in Malaysia. Thus, this research was initiated to analyse the relationship of open space and house price via the techniques of GIS-Hedonic Pricing Model. In this regards, the GIS tool indicates the pattern of the relationship between open space and house price spatially. Meanwhile, Hedonic Pricing Model demonstrates the index of the selected criteria in determining the housing price. This research is a perceptual study of 200 respondents who were the house owners of double-storey terrace houses in four townships, namely Bandar Baru Bangi, Taman Melawati, Subang Jaya and Shah Alam, in Klang Valley. The key research question is whether the relationship between open space and house price exists and the nature of its pattern and intensity. The findings indicate that there is a positive correlation between open space and house price. Correlation analysis reveals that a weak relationship (rs < 0.1 established between the variable of open space and house price (rs = 0.91, N = 200, p = 0.2. Consequently, the rate of house price change is rather small. In overall, this research has achieved its research aims and thus, offers the value added in applying the GIS-Hedonic pricing model in analysing the influence of open space to the house price in the form of spatially and textually.

  8. A Bullet Entered through the Open Mouth and Ended Up in the Parapharyngeal Space and Skull Base

    Directory of Open Access Journals (Sweden)

    Saileswar Goswami

    2015-01-01

    Full Text Available Shot from a revolver from a close range, a bullet pierced the chest of a policeman and entered through the open mouth of a young male person standing behind. The entry wound was found in the cheek mucosa adjacent to the left lower third molar. After hitting and fracturing the body and the ramus of the mandible, the bullet was deflected and was finally lodged in the parapharyngeal space and skull base, anterolateral to the transverse process of the atlas. The great vessels of the neck were not injured. The patient’s condition was very critical but his life could be saved. The bullet was approached through a modified Blair’s incision and was found to be lying over the carotid sheath. It was removed safely and the patient recovered completely.

  9. Ground and excited states of doubly open-shell nuclei from ab initio valence-space Hamiltonians

    CERN Document Server

    Stroberg, S R; Holt, J D; Bogner, S K; Schwenk, A

    2015-01-01

    We present ab initio predictions for ground and excited states of doubly open-shell fluorine and neon isotopes based on chiral two- and three-nucleon interactions. We use the in-medium similarity renormalization group, in both flow-equation and Magnus formulations, to derive mass-dependent sd valence-space Hamiltonians. The experimental ground-state energies are reproduced through neutron number N=14, beyond which a new targeted normal-ordering procedure improves agreement with data and large-scale multi-reference calculations. For spectroscopy, we focus on neutron-rich 23-26F and 24-26Ne isotopes near N=14,16 magic numbers. In all cases we find an agreement with experiment competitive with established phenomenology. Moreover, yrast states are well described in 20Ne and 24Mg, providing an ab initio description of deformation in the medium-mass region.

  10. Open public spaces and street furniture: the potential for increased use of photovoltaics in the built environment

    Energy Technology Data Exchange (ETDEWEB)

    Abbate-Gardner, C. [Officine di Architettura, Rome (Italy)

    1996-07-01

    The trend toward industrializing architectural components, the increasing complexity and multifunctional purpose of buildings and the concern for the CO{sub 2} emissions common to our cities is pushing design research to experiment with new environmentally friendly construction technology. Current experiments in integrating photovoltaic (PV) systems in buildings and the built environment have already been proven to offer numerous advantages. This article focuses on the notable flexibility and adaptability of PV integration in urban structures due to the features of its industrial components. To illustrate this point, I should like to offer a brief overview of some selected examples of the use of PV in public open spaces to demonstrate that it is possible to achieve a positive integration with its environmental context, while enhancing the architectural quality of the PV material and respecting its technological efficiency. (author)

  11. Offset-Free Model Predictive Control of Open Water Channel Based on Moving Horizon Estimation

    Science.gov (United States)

    Ekin Aydin, Boran; Rutten, Martine

    2016-04-01

    Model predictive control (MPC) is a powerful control option which is increasingly used by operational water managers for managing water systems. The explicit consideration of constraints and multi-objective management are important features of MPC. However, due to the water loss in open water systems by seepage, leakage and evaporation a mismatch between the model and the real system will be created. These mismatch affects the performance of MPC and creates an offset from the reference set point of the water level. We present model predictive control based on moving horizon estimation (MHE-MPC) to achieve offset free control of water level for open water canals. MHE-MPC uses the past predictions of the model and the past measurements of the system to estimate unknown disturbances and the offset in the controlled water level is systematically removed. We numerically tested MHE-MPC on an accurate hydro-dynamic model of the laboratory canal UPC-PAC located in Barcelona. In addition, we also used well known disturbance modeling offset free control scheme for the same test case. Simulation experiments on a single canal reach show that MHE-MPC outperforms disturbance modeling offset free control scheme.

  12. Nonlinear Attitude Control of Planar Structures in Space Using Only Internal Controls

    Science.gov (United States)

    Reyhanoglu, Mahmut; Mcclamroch, N. Harris

    1993-01-01

    An attitude control strategy for maneuvers of an interconnection of planar bodies in space is developed. It is assumed that there are no exogeneous torques and that torques generated by joint motors are used as means of control so that the total angular momentum of the multibody system is a constant, assumed to be zero. The control strategy utilizes the nonintegrability of the expression for the angular momentum. Large angle maneuvers can be designed to achieve an arbitrary reorientation of the multibody system with respect to an inertial frame. The theoretical background for carrying out the required maneuvers is summarized.

  13. International Space Station power module thermal control system hydraulic performance

    Energy Technology Data Exchange (ETDEWEB)

    Goldberg, V. [Boeing North American, Inc., Canoga Park, CA (United States). Rocketdyne Div.

    1997-12-31

    The International Space Station (ISS) uses four photovoltaic power modules (PVMs) to provide electric power for the US On-Orbit Segment. The PVMs consist of photovoltaic arrays (PVAs), orbit replaceable units (ORUs), photovoltaic radiators (PVRs), and a thermal control system (TCS). The PVM TCS function is to maintain selected PVM components within their specified operating ranges. The TCS consists of the pump flow control subassembly (PFCS), piping system, including serpentine tubing for individual component heat exchangers, headers/manifolds, fluid disconnect couplings (FQDCs), and radiator (PVR). This paper describes the major design requirements for the TCS and the results of the system hydraulic performance predictions in regard to these requirements and system component sizing. The system performance assessments were conducted using the PVM TCS fluid network hydraulic model developed for predicting system/component pressure losses and flow distribution. Hardy-Cross method of iteration was used to model the fluid network configuration. Assessments of the system hydraulic performance were conducted based on an evaluation of uncertainties associated with the manufacturing and design tolerances. Based on results of the analysis, it was concluded that all design requirements regarding system performance could be met. The hydraulic performance range, enveloping possible system operating parameter variations was determined.

  14. OPEN-LOOP CONTROL OF A BIPOLAR STEPPER MOTORS USING THE SPECIALIZED INTEGRATED CIRCUITS

    Directory of Open Access Journals (Sweden)

    Gheorghe BALUTA

    2004-12-01

    Full Text Available This paper describes the open-loop control of a stepper motors. Bipolar stepper motors can be driven with an L297, an L298N bridge driver and very few external components. With an L298N this configuration drives motors with winding currents up to 2.5A. If very high powers are required an equivalent circuit made with discrete transistors replaces the bridge driver. Together these two chips form a complete microprocessor-to-stepper motor interface. The command signals for the controller L297 are generated through an IBM-PC486 interface. It was developed an open-loop command program written in BorlandC programming language.

  15. Control-Relevant Identification Test Design for Open-Loop Experiment

    Institute of Scientific and Technical Information of China (English)

    张立群; 邵惠鹤

    2004-01-01

    An optimal experiment design (DED) with respect to the use of designing model-base controller was studied. The mean squared error at the setpoint is chosen as the performance criterion. Simple design formulas are derived based on the asymptotic theory. The signal is used for the open loop experiment. The design constraint is the power of the process signal or the process input signal. The results give guideline for identification application.

  16. Opening up a philosophical space in early literacy with Little Beauty by Anthony Browne and the movie King Kong

    Directory of Open Access Journals (Sweden)

    Karin Murris

    2015-04-01

    Full Text Available The article begins with setting the South African educational context for a postgraduate early literacy research project in the foundation phase (ages 4–9. The research examines how philosophy with children (P4C might be part of a solution to current problems in reading comprehension. The second author reports on her P4C action research with her own children as well as her observations of a Grade 2 classroom in a school near Johannesburg. The research shows how the picturebook Little Beauty by Anthony Browne opens up a philosophical space within which children are allowed to draw on their own life experiences and prior knowledge. The project reveals the depth of their thinking when making intra-textual connections between Little Beauty and the movie King Kong. The facilitated philosophical space also makes it possible for the children to make complex philosophical links between the emotion anger, destructive behaviour and the ethico-political dimensions of punishment. Central to this article are the second author’s critical reflections on how her literacy practices as a mother and foundation phase teacher have fundamentally changed as a result of this project. The article concludes with some implications for the teaching of early literacy in South Africa.

  17. Space vehicle electrical power processing distribution and control study. Volume 1: Summary

    Science.gov (United States)

    Krausz, A.

    1972-01-01

    A concept for the processing, distribution, and control of electric power for manned space vehicles and future aircraft is presented. Emphasis is placed on the requirements of the space station and space shuttle configurations. The systems involved are referred to as the processing distribution and control system (PDCS), electrical power system (EPS), and electric power generation system (EPGS).

  18. Open-Switch Fault Diagnosis and Fault Tolerant for Matrix Converter with Finite Control Set-Model Predictive Control

    DEFF Research Database (Denmark)

    Peng, Tao; Dan, Hanbing; Yang, Jian

    2016-01-01

    To improve the reliability of the matrix converter (MC), a fault diagnosis method to identify single open-switch fault is proposed in this paper. The introduced fault diagnosis method is based on finite control set-model predictive control (FCS-MPC), which employs a time-discrete model of the MC...... topology and a cost function to select the best switching state for the next sampling period. The proposed fault diagnosis method is realized by monitoring the load currents and judging the switching state to locate the faulty switch. Compared to the conventional modulation strategies such as carrier...

  19. Dynamics and Control of a Disordered System in Space

    Science.gov (United States)

    Quadrelli, Marco B.

    2013-01-01

    In this paper, we present some ideas regarding the modeling, dynamics and control aspects of granular spacecraft. Granular spacecraft are complex multibody systems composed of a spatially disordered distribution of a large number of elements, for instance a cloud of N grains in orbit, with N greater than 10(exp 3). These grains can be large (Cubesat-size) or small (mm-size), and can be active, i.e., a fully equipped vehicle capable sensing their own position and attitude, and enabled with propulsion means, or entirely passive. The ultimate objective would be to study the behavior of the single grains and of large ensembles of grains in orbit and to identify ways to guide and control the shape of a cloud composed of these grains so that it can perform a useful function in space, for instance, as an element of an optical imaging system for astrophysical applications. This concept, in which the aperture does not need to be continuous and monolithic, would increase the aperture size several times compared to large NASA observatories such as ATLAST, allowing for a true Terrestrial Planet Imager that would be able to resolve exo-planet details and do meaningful spectroscopy on distant world. In the paper, we address the modeling and autonomous operation of a distributed assembly (the cloud) of large numbers of highly miniaturized space-borne elements (the grains). A multi-scale, multi-physics model is proposed of the dynamics of the cloud in orbit, as well as a control law for cloud shape maintenance, and preliminary simulation studies yield an estimate of the computational effort, indicating a scale factor of approximately N(exp 1.4) as a function of the number of grains. A granular spacecraft can be defined as a collection of a large number of space-borne elements (in the 1000s) designed and controlled such that a desirable collective behavior emerges, either from the interactions among neighboring grains, and/or between the grains and the environment. In this paper

  20. Preliminary control system design and analysis for the Space Station Furnace Facility thermal control system

    Science.gov (United States)

    Jackson, M. E.

    1995-01-01

    This report presents the Space Station Furnace Facility (SSFF) thermal control system (TCS) preliminary control system design and analysis. The SSFF provides the necessary core systems to operate various materials processing furnaces. The TCS is defined as one of the core systems, and its function is to collect excess heat from furnaces and to provide precise cold temperature control of components and of certain furnace zones. Physical interconnection of parallel thermal control subsystems through a common pump implies the description of the TCS by coupled nonlinear differential equations in pressure and flow. This report formulates the system equations and develops the controllers that cause the interconnected subsystems to satisfy flow rate tracking requirements. Extensive digital simulation results are presented to show the flow rate tracking performance.

  1. Robust trajectory tracking control of a dual-arm space robot actuated by control moment gyroscopes

    Science.gov (United States)

    Jia, Yinghong; Misra, Arun K.

    2017-08-01

    It is a new design concept to employ control moment gyroscopes (CMGs) as reactionless actuators for space robots. Such actuation has several noticeable advantages such as weak dynamical coupling and low power consumption over traditional joint motor actuation. This paper presents a robust control law for a CMG-actuated space robot in presence of system uncertainties and closed-chain constraints. The control objective is to make the manipulation variables to track the desired trajectories, and reduce the possibility of CMG saturation simultaneously. A reduced-order dynamical equation in terms of independent motion variables is derived using Kane's equations. Desired trajectories of the independent motion variables are derived by minimum-norm trajectory planning algorithm, and an adaptive sliding mode controller with improved adaptation laws is proposed to drive the independent motion variables tracking the desired trajectories. Uniformly ultimate boundedness of the closed loop system is proven using Lyapunov method. The redundancy of the full-order actual control torques is utilized to generate a null torque vector which reduces the possibility of CMG angular momentum saturation while producing no effect on the reduced-order control input. Simulation results demonstrate the effectiveness of the proposed algorithms and the advantage of weak dynamical coupling of the CMG-actuated system.

  2. Operation and test of hybridized silicon p-i-n arrays using open-source array control hardware and software

    Science.gov (United States)

    Moore, Andrew C.; Ninkov, Zoran; Burley, Gregory S.; Forrest, William J.; McMurtry, Craig W.; Avery, Lars E.

    2003-05-01

    A system for controlling and testing high-resolution non-destructive astronomical imagers was constructed using open-source components, both hardware and software. The open-source electronics design, originated by Carnegie Observatories (OCIW) for CCD cameras, was modified, assembled, and augmented with new circuitry which facilitates monitoring of voltages and currents. The electronics was run from Python user interface software based on a design from the University of Rochester. This new software utilized the Numarray and pyFITS modules developed at the Space Telescope Science Institute (STScI). Interfacing to the "dv" FITS image analysis package from the NASA IRTF was also implemented. Python (the STScI language of choice) was used as the primary language for systems integration, scripts for data acquisition, and scripts for data analysis. The DSP clocking software was a mixture of C and Motorola 56303 assembly. An interrupt-driven kernel-mode PCI device driver for Red Hat Linux was written in C, and used the PC processor and memory for image processing and acquisition. Two 1Κ × 1Κ Raytheon SB226-based hybridized silicon p-i-n arrays were operated and tested with the new system at temperatures as low as 10K. Signal path gain, node capacitance, well depth, dark current, and MTF measurements were made and are presented here.

  3. H2-optimal control with generalized state-space models for use in control-structure optimization

    Science.gov (United States)

    Wette, Matt

    1991-01-01

    Several advances are provided solving combined control-structure optimization problems. The author has extended solutions from H2 optimal control theory to the use of generalized state space models. The generalized state space models preserve the sparsity inherent in finite element models and hence provide some promise for handling very large problems. Also, expressions for the gradient of the optimal control cost are derived which use the generalized state space models.

  4. 城市开放空间中的高层建筑%On high-rise buildings in urban open space

    Institute of Scientific and Technical Information of China (English)

    杨玉倩

    2012-01-01

    In order to solve the relationship between the urban high-rise buildings and the urban open space,the paper illustrates the understanding of the urban open space and the urban high-rise buildings,and points out the urban open space and the urban high-rise buildings are inseparable integrity and the cities can be more attractive and harmonious with their mutual coordination.%为了解决好城市高层建筑与城市开放空间之间的关系,阐述了对城市开放空间及城市高层建筑的理解,指出城市开放空间与城市高层建筑是不可分割的整体,两者只有相互协调才能使城市更加美丽、和谐。

  5. Open-Loop Control in Quantum Optics: Two-Level Atom in Modulated Optical Field

    CERN Document Server

    Saifullah, Sergei

    2008-01-01

    The methods of mathematical control theory are widely used in the modern physics, but still they are less popular in quantum science. We will discuss the aspects of control theory, which are the most useful in applications to the real problems of quantum optics. We apply this technique to control the behavior of the two-level quantum particles (atoms) in the modulated external optical field in the frame of the so called "semi classical model", where quantum two-level atomic system (all other levels are neglected) interacts with classical electromagnetic field. In this paper we propose a simple model of feedforward (open-loop) control for the quantum particle system, which is a basement for further investigation of two-level quantum particle in the external one-dimensional optical field.

  6. Onboard Space Autonomy Through Integration of Health Management and Control Reconfiguration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The main objective of this Phase II effort is to develop integrated health management and control reconfiguration algorithms that allow future space systems to...

  7. Onboard Space Autonomy Through Integration of Health Management and Control Reconfiguration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — In this SBIR project we propose to integrate spacecraft control and vehicle health functions to improve the robustness and productivity of space operations. The main...

  8. Digital acquisition and wavelength control of seed laser for space-based Lidar applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR Phase I proposes to establish the feasibility of using a space qualifiable Field Programmable Gate Array (FPGA) based digital controller to autonomously...

  9. Leveraging master-slave OpenFlow controller arrangement to improve control plane resiliency in SD-EONs.

    Science.gov (United States)

    Chen, Xiaoliang; Zhao, Bin; Ma, Shoujiang; Chen, Cen; Hu, Daoyun; Zhou, Wenshuang; Zhu, Zuqing

    2015-03-23

    In this paper, we study how to improve the control plane resiliency of software-defined elastic optical networks (SD-EONs) and design a master-slave OpenFlow (OF) controller arrangement. Specifically, we introduce two OF controllers (OF-Cs), i.e., the master and slave OF-Cs, and make them work in a collaborative way to protect the SD-EON against controller failures. We develop a controller communication protocol (CCP) to facilitate the cooperation of the two OF-Cs. With the CCP, the master OF-C (M-OF-C) can synchronize network status to the slave OF-C (S-OF-C) in real time, while S-OF-C can quickly detect the failure of M-OF-C and take over the network control and management (NC&M) tasks timely to avoid service disruption. We implement the proposed framework in an SD-EON control plane testbed built with high-performance servers, and perform NC&M experiments with different network failure scenarios to demonstrate its effectiveness. Experimental results indicate that the proposed system can restore services in both the data and control planes of SD-EON jointly while maintaining relatively good scalability. To the best of our knowledge, this is the first demonstration that realizes control plane resiliency in SD-EONs.

  10. Nonlinear State Space Modeling and System Identification for Electrohydraulic Control

    Directory of Open Access Journals (Sweden)

    Jun Yan

    2013-01-01

    Full Text Available The paper deals with nonlinear modeling and identification of an electrohydraulic control system for improving its tracking performance. We build the nonlinear state space model for analyzing the highly nonlinear system and then develop a Hammerstein-Wiener (H-W model which consists of a static input nonlinear block with two-segment polynomial nonlinearities, a linear time-invariant dynamic block, and a static output nonlinear block with single polynomial nonlinearity to describe it. We simplify the H-W model into a linear-in-parameters structure by using the key term separation principle and then use a modified recursive least square method with iterative estimation of internal variables to identify all the unknown parameters simultaneously. It is found that the proposed H-W model approximates the actual system better than the independent Hammerstein, Wiener, and ARX models. The prediction error of the H-W model is about 13%, 54%, and 58% less than the Hammerstein, Wiener, and ARX models, respectively.

  11. Modeling, system identification, and control for slosh-free motion of an open container of liquid

    Energy Technology Data Exchange (ETDEWEB)

    Feddema, J.; Baty, R.; Dykhuizen, R.; Dohrmann, C.; Parker, G.; Robinett, R.; Romero, V.; Schmitt, D.

    1996-04-01

    This report discusses work performed under a Cooperative Research And Development Agreement (CRADA) with Corning, Inc., to analyze and test various techniques for controlling the motion of a high speed robotic arm carrying an open container of viscous liquid, in this case, molten glass. A computer model was generated to estimate the modes of oscillation of the liquid based on the shape of the container and the viscosity of the liquid. This fluid model was experimentally verified and tuned based on experimental data from a capacitive sensor on the side of the container. A model of the robot dynamics was also developed and verified through experimental tests on a Fanuc S-800 robot arm. These two models were used to estimate the overall modes of oscillation of an open container of liquid being carried by a robot arm. Using the estimated modes, inverse dynamic control techniques were used to determine a motion profile which would eliminate waves on the liquid`s surface. Experimental tests showed that residual surface waves in an open container of water at the end of motion were reduced by over 95% and that in-motion surface waves were reduced by over 75%.

  12. Decentralized adaptive sliding mode control of a space robot actuated by control moment gyroscopes

    Institute of Scientific and Technical Information of China (English)

    Jia Yinghong; Xu Shijie

    2016-01-01

    An adaptive sliding mode control (ASMC) law is proposed in decentralized scheme for trajectory tracking control of a new concept space robot. Each joint of the system is a free ball joint capable of rotating with three degrees of freedom (DOF). A cluster of control moment gyroscopes (CMGs) is mounted on each link and the base to actuate the system. The modified Rodrigues parameters (MRPs) are employed to describe the angular displacements, and the equations of motion are derived using Kane’s equations. The controller for each link or the base is designed sep-arately in decentralized scheme. The unknown disturbances, inertia parameter uncertainties and nonlinear uncertainties are classified as a ‘‘lumped” matched uncertainty with unknown upper bound, and a continuous sliding mode control (SMC) law is proposed, in which the control gain is tuned by the improved adaptation laws for the upper bound on norm of the uncertainty. A gen-eral amplification function is designed and incorporated in the adaptation laws to reduce the control error without conspicuously increasing the magnitude of the control input. Uniformly ultimate boundedness of the closed loop system is proved by Lyapunov’s method. Simulation results based on a three-link system verify the effectiveness of the proposed controller.

  13. Decentralized adaptive sliding mode control of a space robot actuated by control moment gyroscopes

    Directory of Open Access Journals (Sweden)

    Jia Yinghong

    2016-06-01

    Full Text Available An adaptive sliding mode control (ASMC law is proposed in decentralized scheme for trajectory tracking control of a new concept space robot. Each joint of the system is a free ball joint capable of rotating with three degrees of freedom (DOF. A cluster of control moment gyroscopes (CMGs is mounted on each link and the base to actuate the system. The modified Rodrigues parameters (MRPs are employed to describe the angular displacements, and the equations of motion are derived using Kane’s equations. The controller for each link or the base is designed separately in decentralized scheme. The unknown disturbances, inertia parameter uncertainties and nonlinear uncertainties are classified as a “lumped” matched uncertainty with unknown upper bound, and a continuous sliding mode control (SMC law is proposed, in which the control gain is tuned by the improved adaptation laws for the upper bound on norm of the uncertainty. A general amplification function is designed and incorporated in the adaptation laws to reduce the control error without conspicuously increasing the magnitude of the control input. Uniformly ultimate boundedness of the closed loop system is proved by Lyapunov’s method. Simulation results based on a three-link system verify the effectiveness of the proposed controller.

  14. A Fault-tolerable Control Scheme for an Open-frame Underwater Vehicle

    Directory of Open Access Journals (Sweden)

    Huang Hai

    2014-05-01

    Full Text Available Open-frame is one of the major types of structures of Remote Operated Vehicles (ROV because it is easy to place sensors and operations equipment on- board. Firstly, this paper designed a petri-based recurrent neural network (PRFNN to improve the robustness with response to nonlinear characteristics and strong disturbance of an open-frame underwater vehicle. A threshold has been set in the third layer to reduce the amount of calculations and regulate the training process. The whole network convergence is guaranteed with the selection of learning rate parameters. Secondly, a fault tolerance control (FTC scheme is established with the optimal allocation of thrust. Infinity-norm optimization has been combined with 2-norm optimization to construct a bi-criteria primal-dual neural network FTC scheme. In the experiments and simulation, PRFNN outperformed fuzzy neural networks in motion control, while bi-criteria optimization outperformed 2-norm optimization in FTC, which demonstrates that the FTC controller can improve computational efficiency, reduce control errors, and implement fault tolerable thrust allocation.

  15. A self-tuning digital-driver for open-loop control of stepping-motors

    Energy Technology Data Exchange (ETDEWEB)

    Okada, T.; Hori, N. [Tsukuba Univ., Tsukuba, Ibarki (Japan). Intelligent Interaction Technologies, Graduate School of Systems and Information Engineering

    2010-08-13

    Stepping motors are commonly used as actuators in industrial control applications because of the their high torque-to-weight ratio, precise and quick positioning, and self-hold capability. They can also be controlled in an open-loop fashion using a proper driver. This paper described the design of an experimental digital driver, which contained both fixed and adjustable gains. It also discussed a current regulation problem for a stepping-motor which underwent rapid and large changes in its gains. An open-loop nature of a stepping motor could be preserved using only signals that are readily available in the driver and do not require neither the angular position of the shaft nor its rate. Specifically, the paper discussed the stepping motor and driver, parameter variations, dead-zone compensation, nonlinear digital filter, and anti-aliasing filter. The self-tuning algorithm was also presented with particular reference to background controller design and self tuning pre-compensator. The experiments and parameters used in the experiments were also described. It was concluded that stable and safe operations can be achieved using a combination of fixed controller blocks and precompensator blocks with self-tuning parameters, which change as the speed of rotation varies. For this method to work, it is important to include a dead-zone compensator and a nonlinear digital filter and an anti-aliasing filter. 7 refs., 1 tab., 15 figs.

  16. A Fault-tolerable Control Scheme for an Open-frame Underwater Vehicle

    Directory of Open Access Journals (Sweden)

    Huang Hai

    2014-05-01

    Full Text Available Open-frame is one of the major types of structures of Remote Operated Vehicles (ROV because it is easy to place sensors and operations equipment onboard. Firstly, this paper designed a petri-based recurrent neural network (PRFNN to improve the robustness with response to nonlinear characteristics and strong disturbance of an open-frame underwater vehicle. A threshold has been set in the third layer to reduce the amount of calculations and regulate the training process. The whole network convergence is guaranteed with the selection of learning rate parameters. Secondly, a fault tolerance control (FTC scheme is established with the optimal allocation of thrust. Infinity-norm optimization has been combined with 2-norm optimization to construct a bi-criteria primal-dual neural network FTC scheme. In the experiments and simulation, PRFNN outperformed fuzzy neural networks in motion control, while bi-criteria optimization outperformed 2-norm optimization in FTC, which demonstrates that the FTC controller can improve computational efficiency, reduce control errors, and implement fault tolerable thrust allocation.

  17. An ActiveX Control Based on OpenGL%基于OpenGL的ActiveX控件的实现

    Institute of Scientific and Technical Information of China (English)

    杨日容; 杨承志; 杨晓洪

    2005-01-01

    ActiveX控件是当前开发各种应用程序的一项重要技术,是一种能与其它程序交互通信的程序体系结构.OpenGL则是一种功能强大的三维图形开发工具,利用OpenGL可以生成真彩的三维动态场景.文章在介绍OpenGL及ActiveX控件技术的基础上详细介绍了在Visual C++6.0的环境下开发基于OpenGL的三维动画的方法,并把它封装为ActiveX控件,最后把该控件应用到常用的演示文稿制作软件Powerpoint2000中,实现了在幻灯片中三维动画的显示与控制.

  18. Comparative Effectiveness of Cancer Control and Survival after Robot-Assisted versus Open Radical Prostatectomy.

    Science.gov (United States)

    Hu, Jim C; O'Malley, Padraic; Chughtai, Bilal; Isaacs, Abby; Mao, Jialin; Wright, Jason D; Hershman, Dawn; Sedrakyan, Art

    2017-01-01

    Robot-assisted surgery has been rapidly adopted in the U.S. for prostate cancer. Its adoption has been driven by market forces and patient preference, and debate continues regarding whether it offers improved outcomes to justify the higher cost relative to open surgery. We examined the comparative effectiveness of robot-assisted vs open radical prostatectomy in cancer control and survival in a nationally representative population. This population based observational cohort study of patients with prostate cancer undergoing robot-assisted radical prostatectomy and open radical prostatectomy during 2003 to 2012 used data captured in the SEER (Surveillance, Epidemiology, and End Results)-Medicare linked database. Propensity score matching and time to event analysis were used to compare all cause mortality, prostate cancer specific mortality and use of additional treatment after surgery. A total of 6,430 robot-assisted radical prostatectomies and 9,161 open radical prostatectomies performed during 2003 to 2012 were identified. The use of robot-assisted radical prostatectomy increased from 13.6% in 2003 to 2004 to 72.6% in 2011 to 2012. After a median followup of 6.5 years (IQR 5.2-7.9) robot-assisted radical prostatectomy was associated with an equivalent risk of all cause mortality (HR 0.85, 0.72-1.01) and similar cancer specific mortality (HR 0.85, 0.50-1.43) vs open radical prostatectomy. Robot-assisted radical prostatectomy was also associated with less use of additional treatment (HR 0.78, 0.70-0.86). Robot-assisted radical prostatectomy has comparable intermediate cancer control as evidenced by less use of additional postoperative cancer therapies and equivalent cancer specific and overall survival. Longer term followup is needed to assess for differences in prostate cancer specific survival, which was similar during intermediate followup. Our findings have significant quality and cost implications, and provide reassurance regarding the adoption of more

  19. Approximate controllability of infinite dimensional linear systems in nonreflexive state spaces

    Institute of Scientific and Technical Information of China (English)

    Xin YU; Chao XU

    2005-01-01

    This paper deals with the problem of approximate controllability of infinite dimensional linear systems in nonreflexive state spaces.A necessary and sufficient condition for approximate controllability via Lp([0,T],U),1≤p<∞ is obtained,where Lp([0,T],U) is the control function space.

  20. Aspects of Cultural Landscape Application on Classical Stage Art. Ballet Performance in the Open Space as a Significant Element of the Cultural Landscape

    Directory of Open Access Journals (Sweden)

    Jelena Lebedeva

    2016-04-01

    Full Text Available The article examines the applications aspects of cultural landscape for the preparation of the classical performing arts staging. Research findings highlighted that the cultural landscape (parks, estates, castles, bastions, etc. objects occupies an increasingly important role in public recreation and classical art development programs. At the same time it is noted that event’s aesthetic and emotional quality suffers due to the fact that no specific attention was given for the preparation of the event space. More methodological materials are necessary for preparation of this type of design spaces. In Lithuania classical performing arts events in cultural landscape open spaces are based on XVI–XVII century tradition and has good prospects for modern development. A review of some of the classical art events installations, based on the importance of quality of open spaces influence on the emotional impact, that should be an integral part of the cultural event. The author summarizes his experience of ballet events in open spaces in the cultural landscape – Klaipėda, Trakai. Presented is Tchaikovsky's ballet “Swan Lake” construction in Klaipėda John Hill project that includes infrastructure and environmental design concept: audience space, stage design, stage design performance solutions. Analogous key decisions are later adapted to the ballet performance in the natural environment of the lake Trakai. Experience of this project dictated the necessity of deeper understanding and methodological basis for the classical performing arts analysis and design.

  1. Turbidity management during flushing-flows: A model for open-loop control

    Science.gov (United States)

    Fovet, Ophelie; Litrico, Xavier; Belaud, Gilles

    2012-04-01

    Fixed algae developments induce strong constraints for the management of open-channel networks. They cause clogging issues on hydraulic devices and can sometimes lead to water quality alteration. An original strategy to limit the algal biomass is to carry out regular flushes. A flush is performed by increasing the hydraulic shear conditions using the hydraulic structures of the canal. Consequently to the shear stress increase, a part of the fixed algae is detached, then re-suspended into the water column, and finally transported into the canal network. This leads to a peak of turbidity that needs to be controlled. The present paper proposes a quasi-linear model of the turbidity response to a discharge increase, that can be used for automatic controller design. The model parameters are identified on a real network. The calibration is based on continuous monitoring of water turbidity. Flushes are simulated on the whole branch and on an intermediate reach in order to test the ability of the model to simulate the propagation of a turbidity peak. Then, the model is used to develop an open-loop controller of turbidity for flush design. The efficiency of a flush will depend on its amplitude and duration. The design objective consists in maximizing the algae detachment without exceeding a maximal turbidity level, and using as little water as possible. The designed flush is finally tested on a nonlinear model.

  2. Engineering ribosomal leaky scanning and upstream open reading frames for precise control of protein translation

    Science.gov (United States)

    Ferreira, Joshua P; Noderer, William L; Diaz de Arce, Alexander J; Wang, Clifford L

    2014-01-01

    We have employed upstream open reading frames (uORFs) to systematically tune the translation levels of recombinant proteins. We present the design principles that guided the development of this technology and provide information that may help others in implementing synthetic uORFs for their own applications. We also report on recent applications to our own research projects, including the coupling of uORF and translation initiation site (TIS) engineering with small molecule-inducible post-translational control. Finally, we discuss opportunities to investigate and potentially engineer gene-specific translational responses to cellular stress. PMID:24637490

  3. Coherent open-loop optimal control of light-harvesting dynamics

    CERN Document Server

    Caruso, Filippo; Calarco, Tommaso; Huelga, Susana F; Plenio, Martin B

    2011-01-01

    We apply theoretically open-loop quantum optimal control techniques to provide methods for the verification of various quantum coherent transport mechanisms in natural and artificial light-harvesting complexes under realistic experimental constraints. We demonstrate that optimally shaped laser pulses allow to faithfully prepare the photosystem in specified initial states (such as localized excitation or coherent superposition, i.e. propagating and non-propagating states) and to probe efficiently the dynamics. These results provide a path towards the discrimination of the different transport pathways and to the characterization of environmental properties, enhancing our understanding of the role that coherent processes may play in biological complexes.

  4. Inverse synchronization of coupled fractional-order systems through open-plus-closed-loop control

    Indian Academy of Sciences (India)

    Junwei Wang; Li Zeng; Qinghua Ma

    2011-03-01

    In this paper, the inverse synchronization problem of fractional-order dynamical systems is investigated. A general explicit coupling via an open-plus-closed-loop control for inverse synchronization of two arbitrary unidirectionally or bidirectionally coupled fractional-order systems is proposed. The inverse synchronization is proved analytically based on the stability theorem of the fractional differential equations. A key feature of this proposed scheme is that it can be applied not only to nonchaotic but also to chaotic fractional-order systems whenever they exhibit regular or irregular oscillations. Feasibility of the proposed inverse synchronization scheme is illustrated through numerical simulations.

  5. Landscape scale vegetation-type conversion and fire hazard in the San Francisco bay area open spaces

    Science.gov (United States)

    Russell, W.H.; McBride, J.R.

    2003-01-01

    Successional pressures resulting from fire suppression and reduced grazing have resulted in vegetation-type conversion in the open spaces surrounding the urbanized areas of the San Francisco bay area. Coverage of various vegetation types were sampled on seven sites using a chronosequence of remote images in order to measure change over time. Results suggest a significant conversion of grassland to shrubland dominated by Baccharis pilularison five of the seven sites sampled. An increase in Pseudotsuga menziesii coverage was also measured on the sites where it was present. Increases fuel and fire hazard were determined through field sampling and use of the FARSITE fire area simulator. A significant increase in biomass resulting from succession of grass-dominated to shrub-dominated communities was evident. In addition, results from the FARSITE simulations indicated significantly higher fire-line intensity, and flame length associated with shrublands over all other vegetation types sampled. These results indicate that the replacement of grass dominated with shrub-dominated landscapes has increased the probability of high intensity fires. ?? 2003 Elsevier Science B.V. All rights reserved.

  6. Modular space vehicle boards, control software, reprogramming, and failure recovery

    Energy Technology Data Exchange (ETDEWEB)

    Judd, Stephen; Dallmann, Nicholas; McCabe, Kevin; Delapp, Jerry; Prichard, Dean; Proicou, Michael; Seitz, Daniel; Stein, Paul; Michel, John; Tripp, Justin; Palmer, Joseph; Storms, Steven

    2017-09-12

    A space vehicle may have a modular board configuration that commonly uses some or all components and a common operating system for at least some of the boards. Each modular board may have its own dedicated processing, and processing loads may be distributed. The space vehicle may be reprogrammable, and may be launched without code that enables all functionality and/or components. Code errors may be detected and the space vehicle may be reset to a working code version to prevent system failure.

  7. Contralaterally Controlled Functional Electrical Stimulation for Recovery of Elbow Extension and Hand Opening After Stroke

    Science.gov (United States)

    Knutson, Jayme S.; Harley, Mary Y.; Hisel, Terri Z.; Makowski, Nathaniel S.; Chae, John

    2014-01-01

    Objective The aims of this study were to determine whether patients with moderate-to-severe upper limb hemiplegia could use contralaterally controlled functional electrical stimulation at the arm and the hand (Arm+Hand CCFES) at home and to evaluate the feasibility of the Arm+Hand CCFES to reduce arm and hand motor impairment. Design With the Arm+Hand CCFES, the paretic elbow and hand extensors were stimulated with intensities proportional to the degree of elbow extension and hand opening, respectively, of the contralateral unimpaired side. For 1 2 wks, four participants with chronic (≥6 mos) upper limb hemiplegia received ∼7 hrs per week of self-administered home-based stimulation-mediated elbow extension and hand opening exercise plus ∼2.5 hrs per week of therapist-supervised laboratory-based stimulation-assisted functional task practice. Assessments of upper limb impairment were made at pretreatment, posttreatment, and 1 mo after treatment. Results All four participants were able to use the Arm+Hand CCFES system at home either independently or with very minimal assistance from a caregiver. All four participants had increases in the Fugl-Meyer score (1–9 points) and the Wolf Motor Function Test (0.2–0.8 points) and varying degrees of improvement in maximum hand opening, maximum elbow extension, and simultaneous elbow extension and hand opening. Conclusions The Arm+Hand CCFES can be successfully administered in stroke patients with moderate-to-severe impairment and can reduce various aspects of upper limb impairment. A larger efficacy study is warranted. PMID:24508938

  8. Brain Machine Interfaces for Robotic Control in Space Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR will study the application of a brain machine interface (BMI) to enable crew to remotely operate and monitor robots from inside a flight vehicle, habitat...

  9. Experimental evaluation of open-loop UpLink Power Control using ACTS

    Science.gov (United States)

    Dissanayake, Asoka

    1995-01-01

    The present investigation deals with the implementation of open-loop up-link power control using a beacon signal in the down-link frequency band as the control parameter. A power control system was developed and tested using the ACTS satellite. ACTS carries beacon signals in both up- and down-link bands with which the relationship between the up- and down-link fading can be established. A power controlled carrier was transmitted to the ACTS satellite from a NASA operated ground station and the transponded signal was received at COMSAT Laboratories using a terminal that was routinely used to monitor the two ACTS beacon signals. The experiment ran for a period of approximately six months and the collected data were used to evaluate the performance of the power control system. A brief review of propagation factors involved in estimating the up-link fade using a beacon signal in the down-link band are presented. The power controller design and the experiment configuration are discussed. Results of the experiment are discussed.

  10. The Political Economy of "Open Regionalism" and Education in Small (and Micro) States: The Construction of the Caribbean Educational Policy Space in CARICOM

    Science.gov (United States)

    Jules, Tavis D.

    2014-01-01

    In this era of amplified regionalisation, the Economic Commission for Latin America and the Caribbean's (ECLAC) conceptualisation of 'open regionalism' is pertinent to examine the role of regional governance mechanisms in constructing what I call the "Caribbean Educational Policy Space." With the aid of a latent content…

  11. The Political Economy of "Open Regionalism" and Education in Small (and Micro) States: The Construction of the Caribbean Educational Policy Space in CARICOM

    Science.gov (United States)

    Jules, Tavis D.

    2014-01-01

    In this era of amplified regionalisation, the Economic Commission for Latin America and the Caribbean's (ECLAC) conceptualisation of 'open regionalism' is pertinent to examine the role of regional governance mechanisms in constructing what I call the "Caribbean Educational Policy Space." With the aid of a latent content analysis of…

  12. A microporous Cu-MOF with optimized open metal sites and pore spaces for high gas storage and active chemical fixation of CO2.

    Science.gov (United States)

    Gao, Chao-Ying; Tian, Hong-Rui; Ai, Jing; Li, Lei-Jiao; Dang, Song; Lan, Ya-Qian; Sun, Zhong-Ming

    2016-09-25

    A microporous Cu-MOF with optimized open metal sites and pore space was constructed based on a designed bent ligand; it exhibits high-capacity multiple gas storage under atmospheric pressure and efficient catalytic activity for chemical fixation of CO2 under mild conditions.

  13. Control of Energy Density inside a Disordered Medium by Coupling to Open or Closed Channels

    Science.gov (United States)

    Sarma, Raktim; Yamilov, Alexey G.; Petrenko, Sasha; Bromberg, Yaron; Cao, Hui

    2016-08-01

    We demonstrate experimentally the efficient control of light intensity distribution inside a random scattering system. The adaptive wave front shaping technique is applied to a silicon waveguide containing scattering nanostructures, and the on-chip coupling scheme enables access to all input spatial modes. By selectively coupling the incident light to the open or closed channels of the disordered system, we not only vary the total energy stored inside the system by a factor of 7.4, but also change the energy density distribution from an exponential decay to a linear decay and to a profile peaked near the center. This work provides an on-chip platform for controlling light-matter interactions in turbid media.

  14. Performance analysis and overload control of an open service access (OSA) architecture

    Science.gov (United States)

    Andersson, Jens K.; Nyberg, Christian; Kihl, Maria

    2003-08-01

    The trend of the service architectures developed in telecommunications today is that they should be open in the sense that they can communicate over the borders of different networks. Instead of each network having their own service architecture with their own applications, all networks should be able to use the same applications. 3GPP, the organization developing specifications for the 3G networks has specified the standard Open Service Access (OSA), as a part of the 3G specification. OSA offers different Application Protocol Interfaces that enable an application that resides outside a network to use the capabilities of the network. This paper analyses the performance of an OSA gateway. It is examined how the overload control can be dealt with in a way to best satisfy the operators and the 3'rd parties. There are some guiding principles in the specifications, but a lot of decisions have to be made by the implementors of application servers and OSA gateways. Proposals of different requirements for an OSA architecture exist such as, minimum amount of accepted calls per second and time constraint for the maximal total delay for an application. Maximal and fair throughput have to be prioritized from the 3'rd parties view, but profit is the main interest from the operators point of view. Therefore this paper examines a priority based proposal of an overload control mechanism taking these aspects and requirements into account.

  15. On Sequence Learning Models: Open-loop Control Not Strictly Guided by Hick's Law.

    Science.gov (United States)

    Pavão, Rodrigo; Savietto, Joice P; Sato, João R; Xavier, Gilberto F; Helene, André F

    2016-03-15

    According to the Hick's law, reaction times increase linearly with the uncertainty of target stimuli. We tested the generality of this law by measuring reaction times in a human sequence learning protocol involving serial target locations which differed in transition probability and global entropy. Our results showed that sigmoid functions better describe the relationship between reaction times and uncertainty when compared to linear functions. Sequence predictability was estimated by distinct statistical predictors: conditional probability, conditional entropy, joint probability and joint entropy measures. Conditional predictors relate to closed-loop control models describing that performance is guided by on-line access to past sequence structure to predict next location. Differently, joint predictors relate to open-loop control models assuming global access of sequence structure, requiring no constant monitoring. We tested which of these predictors better describe performance on the sequence learning protocol. Results suggest that joint predictors are more accurate than conditional predictors to track performance. In conclusion, sequence learning is better described as an open-loop process which is not precisely predicted by Hick's law.

  16. Eruptions arising from tidally controlled periodic openings of rifts on Enceladus.

    Science.gov (United States)

    Hurford, T A; Helfenstein, P; Hoppa, G V; Greenberg, R; Bills, B G

    2007-05-17

    In 2005, plumes were detected near the south polar region of Enceladus, a small icy satellite of Saturn. Observations of the south pole revealed large rifts in the crust, informally called 'tiger stripes', which exhibit higher temperatures than the surrounding terrain and are probably sources of the observed eruptions. Models of the ultimate interior source for the eruptions are under consideration. Other models of an expanding plume require eruptions from discrete sources, as well as less voluminous eruptions from a more extended source, to match the observations. No physical mechanism that matches the observations has been identified to control these eruptions. Here we report a mechanism in which temporal variations in tidal stress open and close the tiger-stripe rifts, governing the timing of eruptions. During each orbit, every portion of each tiger stripe rift spends about half the time in tension, which allows the rift to open, exposing volatiles, and allowing eruptions. In a complementary process, periodic shear stress along the rifts also generates heat along their lengths, which has the capacity to enhance eruptions. Plume activity is expected to vary periodically, affecting the injection of material into Saturn's E ring and its formation, evolution and structure. Moreover, the stresses controlling eruptions imply that Enceladus' icy shell behaves as a thin elastic layer, perhaps only a few tens of kilometres thick.

  17. Intravenous Immunoglobulin Therapy in Pediatric Narcolepsy: A Nonrandomized, Open-Label, Controlled, Longitudinal Observational Study

    Science.gov (United States)

    Lecendreux, Michel; Berthier, Johanna; Corny, Jennifer; Bourdon, Olivier; Dossier, Claire; Delclaux, Christophe

    2017-01-01

    Study Objectives: Previous case reports of intravenous immunoglobulins (IVIg) in pediatric narcolepsy have shown contradictory results. Methods: This was a nonrandomized, open-label, controlled, longitudinal observational study of IVIg use in pediatric narcolepsy with retrospective data collection from medical files obtained from a single pediatric national reference center for the treatment of narcolepsy in France. Of 56 consecutively referred patients with narcolepsy, 24 received IVIg (3 infusions administered at 1-mo intervals) in addition to standard care (psychostimulants and/or anticataplectic agents), and 32 continued on standard care alone (controls). Results: For two patients in each group, medical files were unavailable. Of the 22 IVIg patients, all had cerebrospinal fluid (CSF) hypocretin ≤ 110 pg/mL and were HLA-DQB1*06:02 positive. Of the 30 control patients, 29 were HLA-DQB1*06:02 positive and of those with available CSF measurements, all 12 had hypocretin ≤ 110 pg/mL. Compared with control patients, IVIg patients had shorter disease duration, shorter latency to sleep onset, and more had received H1N1 vaccination. Mean (standard deviation) follow-up length was 2.4 (1.1) y in the IVIg group and 3.9 (1.7) y in controls. In multivariate-adjusted linear mixed-effects analyses of change from baseline in Ullanlinna Narcolepsy Scale (UNS) scores, high baseline UNS, but not IVIg treatment, was associated with a reduction in narcolepsy symptoms. On time-to-event analysis, among patients with high baseline UNS scores, control patients achieved a UNS score narcolepsy symptoms were not significantly reduced by IVIg. However, in patients with high baseline symptoms, a subset of IVIg-treated patients achieved remission more rapidly than control patients. Commentary: A commentary on this article appears in this issue on page 363. Citation: Lecendreux M, Berthier J, Corny J, Bourdon O, Dossier C, Delclaux C. Intravenous immunoglobulin therapy in pediatric

  18. Effects of modifications to the space shuttle entry guidance and control systems

    Science.gov (United States)

    Powell, R. W.; Stone, H. W.; Rowell, L. F.

    1976-01-01

    A nonlinear six degree of freedom entry simulation study was conducted to identify space shuttle guidance and control system software modifications which reduce the control system sensitivity to the guidance system sampling frequency. Several modifications which eliminated the control system sensitivity and associated control limit cycling were examined. The result of the modifications was a reduction in required reaction control system fuel.

  19. Quantum-control-landscape structure viewed along straight paths through the space of control fields

    Science.gov (United States)

    Nanduri, Arun; Ho, Tak-San; Rabitz, Herschel

    2016-02-01

    The dynamics of closed quantum systems may be manipulated by using an applied field to achieve a control objective value for a physical goal. The functional relationship between the applied field and the objective value forms a quantum control landscape, and the optimization process consists of a guided climb up the landscape from the bottom to the top. Two classes of landscape features are important for understanding the ease of finding an optimal control field. The first class of topological landscape features has been proven to be especially simple in that no suboptimal local maxima exist (upon satisfaction of certain assumptions), which partially accounts for the ease of finding optimal fields. Complementary to the topology, the second class of features entails the landscape structure, characterizing the sinuous nature of the paths leading to an optimal control field. Previous work found that the landscape structure is also particularly simple, as excursions up the landscape guided by a gradient algorithm correspond to nearly straight paths through the space of control fields. In this paper we take an alternative approach to examining landscape structure by constructing, and then following, exactly straight trajectories in control space. Each trajectory starts at a corresponding point on the bottom of the landscape and ends at an associated point on the top, with the observable values taken either as the state-to-state transition probability, the expectation value of a general observable, or the distance from a desired unitary transformation. In some cases the starting point is at a suboptimal critical-point saddle, with the goal, again, of following a straight field path to the optimal objective yield or another suboptimal critical point. We find that the objective value almost always rises monotonically upon following a straight control path from one critical point to another, which shows that landscape structure is very simple, being devoid of rough bumps

  20. Research on Control Method Based on Real-Time Operational Reliability Evaluation for Space Manipulator

    Directory of Open Access Journals (Sweden)

    Yifan Wang

    2014-05-01

    Full Text Available A control method based on real-time operational reliability evaluation for space manipulator is presented for improving the success rate of a manipulator during the execution of a task. In this paper, a method for quantitative analysis of operational reliability is given when manipulator is executing a specified task; then a control model which could control the quantitative operational reliability is built. First, the control process is described by using a state space equation. Second, process parameters are estimated in real time using Bayesian method. Third, the expression of the system's real-time operational reliability is deduced based on the state space equation and process parameters which are estimated using Bayesian method. Finally, a control variable regulation strategy which considers the cost of control is given based on the Theory of Statistical Process Control. It is shown via simulations that this method effectively improves the operational reliability of space manipulator control system.

  1. Search Space Calculation to Improve Parameter Estimation of Excitation Control Systems

    OpenAIRE

    2013-01-01

    A method to calculate the search space for each parameter in an excitation control system is presented in this paper. The calculated search space is intended to reduce the number of parameter solution sets that can be found by an estimation algorithm, reducing its processing time. The method considers a synchronous generator time constant range between 4s and 10s, an excitation control system performance index, a controller design technique, and the excitation control system model structure. ...

  2. Quality or quantity? Exploring the relationship between Public Open Space attributes and mental health in Perth, Western Australia.

    Science.gov (United States)

    Francis, Jacinta; Wood, Lisa J; Knuiman, Matthew; Giles-Corti, Billie

    2012-05-01

    Mental health is a public health priority globally. Public Open Space (POS) may enhance mental health by facilitating contact with nature and the development of supportive relationships. Despite growing interest in the influence of the built environment on mental health, associations between POS attributes and mental health remain relatively unexplored. In particular, few studies have examined the relative effects of the quantity and quality of POS within a neighbourhood on mental health. Guided by a social-ecological framework, this study investigated the relationship between POS attributes (i.e., quantity and quality) and better mental health (i.e., low risk of psychological distress) in residents of new housing developments in the Perth metropolitan area, Western Australia. The extent to which relationships between POS attributes and mental health were confounded by psychosocial factors (e.g., social support, sense of community) and frequent use of POS was also explored. Data were obtained from a cross-sectional survey (n = 911), a POS audit, and Geographical Information Systems, and was analysed using logistic regression. Approximately 80% of survey participants were at low risk of psychological distress. Residents of neighbourhoods with high quality POS had higher odds of low psychosocial distress than residents of neighbourhoods with low quality POS. This appeared to be irrespective of whether or not they used POS. However, the quantity of neighbourhood POS was not associated with low psychological distress. From a mental health perspective, POS quality within a neighbourhood appears to be more important than POS quantity. This finding has policy implications and warrants further investigation.

  3. Autonomous Defensive Space Control via On-Board Artificial Neural Networks

    Science.gov (United States)

    2007-04-01

    AUTONOMOUS DEFENSIVE SPACE CONTROL VIA ON-BOARD ARTIFICIAL NEURAL NETWORKS Michael T. Manor, Major, USAF April 2007...TITLE AND SUBTITLE Sutonomous Defensive Space Control via On-Board Artificial Neural Networks 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM...11 HOW ARTIFICIAL NEURAL NETWORKS WORK

  4. Regional assessment of urban impacts on landcover and open space finds a smart urban growth policy performs little better than business as usual.

    Science.gov (United States)

    Thorne, James H; Santos, Maria J; Bjorkman, Jacquelyn H

    2013-01-01

    Assessment of landscape change is critical for attainment of regional sustainability goals. Urban growth assessments are needed because over half the global population now lives in cities, which impact biodiversity, ecosystem structure and ecological processes. Open space protection is needed to preserve these attributes, and provide the resources humans need. The San Francisco Bay Area, California, is challenged to accommodate a population increase of 3.07 million while maintaining the region's ecosystems and biodiversity. Our analysis of 9275 km² in the Bay Area links historic trends for three measures: urban growth, protected open space, and landcover types over the last 70 years to future 2050 projections of urban growth and open space. Protected open space totaled 348 km² (3.7% of the area) in 1940, and expanded to 2221 km² (20.2%) currently. An additional 1038 km² of protected open space is targeted (35.1%). Urban area historically increased from 396.5 km² to 2239 km² (24.1% of the area). Urban growth during this time mostly occurred at the expense of agricultural landscapes (62.9%) rather than natural vegetation. Smart Growth development has been advanced as a preferred alternative in many planning circles, but we found that it conserved only marginally more open space than Business-as-usual when using an urban growth model to portray policies for future urban growth. Scenarios to 2050 suggest urban development on non-urban lands of 1091, 956, or 179 km², under Business-as-usual, Smart Growth and Infill policy growth scenarios, respectively. The Smart Growth policy converts 88% of natural lands and agriculture used by Business-as-usual, while Infill used only 40% of those lands. Given the historic rate of urban growth, 0.25%/year, and limited space available, the Infill scenario is recommended. While the data may differ, the use of an historic and future framework to track these three variables can be easily applied to other metropolitan areas.

  5. Regional assessment of urban impacts on landcover and open space finds a smart urban growth policy performs little better than business as usual.

    Directory of Open Access Journals (Sweden)

    James H Thorne

    Full Text Available Assessment of landscape change is critical for attainment of regional sustainability goals. Urban growth assessments are needed because over half the global population now lives in cities, which impact biodiversity, ecosystem structure and ecological processes. Open space protection is needed to preserve these attributes, and provide the resources humans need. The San Francisco Bay Area, California, is challenged to accommodate a population increase of 3.07 million while maintaining the region's ecosystems and biodiversity. Our analysis of 9275 km² in the Bay Area links historic trends for three measures: urban growth, protected open space, and landcover types over the last 70 years to future 2050 projections of urban growth and open space. Protected open space totaled 348 km² (3.7% of the area in 1940, and expanded to 2221 km² (20.2% currently. An additional 1038 km² of protected open space is targeted (35.1%. Urban area historically increased from 396.5 km² to 2239 km² (24.1% of the area. Urban growth during this time mostly occurred at the expense of agricultural landscapes (62.9% rather than natural vegetation. Smart Growth development has been advanced as a preferred alternative in many planning circles, but we found that it conserved only marginally more open space than Business-as-usual when using an urban growth model to portray policies for future urban growth. Scenarios to 2050 suggest urban development on non-urban lands of 1091, 956, or 179 km², under Business-as-usual, Smart Growth and Infill policy growth scenarios, respectively. The Smart Growth policy converts 88% of natural lands and agriculture used by Business-as-usual, while Infill used only 40% of those lands. Given the historic rate of urban growth, 0.25%/year, and limited space available, the Infill scenario is recommended. While the data may differ, the use of an historic and future framework to track these three variables can be easily applied to other

  6. Open or close the gate - stomata action under the control of phytohormones in drought stress conditions.

    Science.gov (United States)

    Daszkowska-Golec, Agata; Szarejko, Iwona

    2013-01-01

    Two highly specialized cells, the guard cells that surround the stomatal pore, are able to integrate environmental and endogenous signals in order to control the stomatal aperture and thereby the gas exchange. The uptake of CO2 is associated with a loss of water by leaves. Control of the size of the stomatal aperture optimizes the efficiency of water use through dynamic changes in the turgor of the guard cells. The opening and closing of stomata is regulated by the integration of environmental signals and endogenous hormonal stimuli. The various different factors to which the guard cells respond translates into the complexity of the network of signaling pathways that control stomatal movements. The perception of an abiotic stress triggers the activation of signal transduction cascades that interact with or are activated by phytohormones. Among these, abscisic acid (ABA), is the best-known stress hormone that closes the stomata, although other phytohormones, such as jasmonic acid, brassinosteroids, cytokinins, or ethylene are also involved in the stomatal response to stresses. As a part of the drought response, ABA may interact with jasmonic acid and nitric oxide in order to stimulate stomatal closure. In addition, the regulation of gene expression in response to ABA involves genes that are related to ethylene, cytokinins, and auxin signaling. In this paper, recent findings on phytohormone crosstalk, changes in signaling pathways including the expression of specific genes and their impact on modulating stress response through the closing or opening of stomata, together with the highlights of gaps that need to be elucidated in the signaling network of stomatal regulation, are reviewed.

  7. The Library Space Problem, Future Demand, and Collection Control.

    Science.gov (United States)

    Lee, Hur-Li

    1993-01-01

    Outlines a model for determining library collection use, incorporating prediction of future demand and cost analysis to assist collection development librarians determine whether weeding or remote storage is the most economically feasible way to address the space problem in libraries. (13 references) (EA)

  8. Controlled cytotoxicity of plasma treated water formulated by open-air hybrid mode discharge

    Science.gov (United States)

    Lu, P.; Boehm, D.; Cullen, P.; Bourke, P.

    2017-06-01

    Plasma treated liquids (PTLs) provide a means to convey a broad range of effects of relevance for food, environmental, or clinical decontamination, plant growth promotion, and therapeutic applications. Devising the reactive species ingredients and controlling the biological response of PTLs are of great interest. We demonstrate an approach by using an open-air hybrid mode discharge (HMD) to control the principal reactive species composition within plasma treated water (PTW), which is then demonstrated to regulate the cytotoxicity of PTW. The cytotoxicity of HMD produced PTW demonstrates a non-monotonic change over the discharge time. Although hydrogen peroxide and nitrite are not the sole effectors for cell death caused by PTW, using them as principal reactive species indicators, cytotoxicity can be removed and/or enhanced by formulating their concentrations and composition through adjusting the discharge mode and time on-line during PTW generation without the addition of additional working gas or chemical scavengers. This work demonstrates that a hybrid mode discharge can be employed to generate a PTW formulation to control a biological response such as cytotoxicity. This provides insights into how plasma treated liquids may be harnessed for biological applications in a specific and controllable manner.

  9. Let it grow-the open market solution to marijuana control.

    Science.gov (United States)

    Gettman, Jon; Kennedy, Michael

    2014-11-18

    This commentary evaluates regulatory frameworks for the legalized production, sale, and use of marijuana. Specifically, we argue that the primary goal of legalization should be the elimination of the illicit trade in marijuana and that maximizing market participation through open markets and personal cultivation is the best approach to achieving this goal. This argument is based on the assertion that regulatory models based on a tightly controlled government market will fail because they replicate the fatal flaws of the prohibition model. This commentary argues that an examination of the reasons for prohibition's failure-to wit, the inability of government to control the production of marijuana-completely undercuts the basic premise of a tightly controlled market, which depends on the ability of the government to control production. The public interest would be better served by an effective regulatory framework which recognizes and takes advantage of competitive market forces. This analysis argues that reducing teenage access to marijuana requires the elimination of an overcapitalized illicit market. Further, it asserts that this goal and maximization of tax revenue from a legal marijuana market are mutually exclusive objectives.

  10. Building highly available control system applications with Advanced Telecom Computing Architecture and open standards

    Science.gov (United States)

    Kazakov, Artem; Furukawa, Kazuro

    2010-11-01

    Requirements for modern and future control systems for large projects like International Linear Collider demand high availability for control system components. Recently telecom industry came up with a great open hardware specification - Advanced Telecom Computing Architecture (ATCA). This specification is aimed for better reliability, availability and serviceability. Since its first market appearance in 2004, ATCA platform has shown tremendous growth and proved to be stable and well represented by a number of vendors. ATCA is an industry standard for highly available systems. On the other hand Service Availability Forum, a consortium of leading communications and computing companies, describes interaction between hardware and software. SAF defines a set of specifications such as Hardware Platform Interface, Application Interface Specification. SAF specifications provide extensive description of highly available systems, services and their interfaces. Originally aimed for telecom applications, these specifications can be used for accelerator controls software as well. This study describes benefits of using these specifications and their possible adoption to accelerator control systems. It is demonstrated how EPICS Redundant IOC was extended using Hardware Platform Interface specification, which made it possible to utilize benefits of the ATCA platform.

  11. OpenCV在生物力学微形变控制及测试系统中的应用%Application of OpenCV in Biomechanics Micro-deformation Controlling and Testing System

    Institute of Scientific and Technical Information of China (English)

    李曾; 李晋川; 黄学进; 邹远文

    2012-01-01

    为测量生物力学实验中的微形变,组建了微形变控制装置,结合OpenCV的视频采集与图像处理功能,搭建了生物力学微形变控制与非接触性测量系统。该系统在跟踪并测量特征点信息的同时,可获得其周围组织的运动情况以供后期处理。使用该系统测量足部标本随受力改变而发生的跖骨间距变化,获得了跖骨微运动相关参数。%To test the micro-deformation in biomechanics experiments,the controlling part is built and based on the camera control and image processing functions of OpenCV,the biomechanics micro deformation control and non-contract test system is built.The system is able to track and test the feature point and get the deformation message of surrounding tissues to post process.Based on the system,the metatarsals spacing of human foot specimens in different loading situations is tested.Micro-deformation parameter of metatarsus is calculated.

  12. HPC realization of a controlled turbulent round jet using OpenFOAM

    CERN Document Server

    Önder, Asim

    2014-01-01

    The present paper investigates high performance computing abilities of OpenFOAM for a low Reynolds number ($Re_D=2000$) axisymmetric jet subject to multiple zero net mass flux (ZNMF) actuators. First, parallel performance of OpenFOAM is tested by performing a scaling study up to $2048$ processors on a supercomputer of Flemish Supercomputer Center(VSC). Then, a method to improve the parallel efficiency is proposed. The method is based on developing a hybrid concept to calculate the statistical moments. This new concept combines ensemble and time averaging in order to allow data sampling in parallel. The motivation is obtaining a reduction in the walltime to collect turbulent statistics which is observed to be the dominating part in the ZNMF controlled jet flow. Employing this parallel statistical averaging approach in combination with regular grid partitioning parallelism, allowed us conducting DNS cases on $P=624$ processors with an overall speed-up of $S_e=540.56$ and a parallel efficiency of $E_e=0.87$. The...

  13. A comparison of controlled self-pollination and open pollination results based on maize grain quality

    Directory of Open Access Journals (Sweden)

    Hanna Sulewska

    2014-05-01

    Full Text Available Maize (Zea mays L. grain endosperm is triploid (3n, of which 2n come from the male (transferred by pollen and only 1n from the female plant, thus a major impact of the male form can be expected on grain quality parameters. A good example of this relationship is the phenomenon of xenia. The aim of this study was to determine the effect of pollen on grain quality. The field experiment was conducted in 2011; seeds were harvested from eight cultivars: Bosman, Blask, Tur, Kozak, Bielik, Smok, SMH 220 and Kresowiak, derived from free pollination and controlled self-pollination of maize. Analyses of nutrient contents and starch content in the grain were conducted in the laboratory. In addition, 1000 grain weight and the hectoliter weight of all grain samples were recorded. The results confirmed differences in grain quality of maize hybrids obtained by self-pollination and by open pollination. Grain of maize plants obtained by open-pollination was characterised by higher contents of N-free extract and starch, and lower protein content. Undertaking further studies on this subject may indicate specific recommendations for agricultural practice, such as mixtures of hybrids with good combining abilities, which will contribute to improved grain quality without additional costs.

  14. The dynamics and control of large flexible space structures

    Science.gov (United States)

    Bainum, P. M.; Krishna, R.; Kumar, V. K.; Reddy, A. S. S. R.

    1981-01-01

    The dynamics and attitude and shape control of very large, inherently flexible spacecraft systems were investigated. Increasingly more complex examples were examined, beginning with a uniform free-free beam, next a free-free uniform plate/platform and finally by considering a thin shallow spherical shell structure in orbit. The effects devices were modeled. For given sets of assumed actuator locations, the controllability of these systems was first established. Control laws for each of the actuators were developed based on decoupling techniques (including distributed modal control) pole placement algorithms and a application of the linear regulator problem for optical control theory.

  15. A Control Law Definition of the Open Loop Stepping Electric Drive

    Directory of Open Access Journals (Sweden)

    A. B. Krasovskii

    2015-01-01

    Full Text Available The paper considers an open loop stepping electric drive (SEP with electric crushing of a step and motor fed from the controlled current invertor which should meet the requirement that is to trial a free-form guided trajectory with a split-hair accuracy. It is shown that with traditional programmed control, when the SEP forms motor phase currents of identical amplitude and variable frequency proportional to the set speed of movement, there may be considerable errors reducing a trial accuracy of the set movement trajectory, dynamic indicators provoking oscillatory processes, and even loss of motor synchronism because influence on a dynamic moment of the motor is impossible.The paper offers and proves a new way to define a control algorithm adequate to drive parameters and programmed trajectory of movement, providing error minimization and thereby increasing trial accuracy of set parameters of movement and expanding dynamic capabilities of a drive. The essence of the offered way is to use a modified mathematical model of a drive in d,q coordinates with a motor fed by the current source. In this model a programmed trajectory of movement is chosen as an input action while solving the appropriate equations defines the necessary law of control. The paper describes a developed simulation model of the stepping electric drive in the environment of MATLAB – SIMULINK, which has been used to verify and prove an efficiency of the offered method to define a control law via typical examples.It is established that no error trial of set movement trajectory in case it has breaks (jogs is technically unfeasible, as it demands an infinitely high forcing voltage of the power supply to maintain the instant positive or negative phase shifts of currents formed in the motor windings.The obtained results can be used in designing programmable precision SEPs in robots, numerically controlled machine tools, and assembly equipment.

  16. Rat sightings in New York City are associated with neighborhood sociodemographics, housing characteristics, and proximity to open public space.

    Science.gov (United States)

    Walsh, Michael G

    2014-01-01

    Rats are ubiquitous in urban environments and, as established reservoirs for infectious pathogens, present a control priority for public health agencies. New York City (NYC) harbors one of the largest rat populations in the United States, but surprising little study has been undertaken to define rat ecology across varied features of this urban landscape. More importantly, factors that may contribute to increased encounters between rats and humans have rarely been explored. Using city-wide records of rat sightings reported to the NYC Department of Health and Mental Hygiene, this investigation sought to identify sociodemographic, housing, and physical landscape characteristics that are associated with increased rat sightings across NYC census tracts. A hierarchical Bayesian conditional autoregressive Poisson model was used to assess these associations while accounting for spatial heterogeneity in the variance. Closer proximity to both subway lines and recreational public spaces was associated with a higher concentration of rat sightings, as was a greater presence of older housing, vacant housing units, and low education among the population. Moreover, these aspects of the physical and social landscape accurately predicted rat sightings across the city. These findings have identified specific features of the NYC urban environment that may help to provide direct control targets for reducing human-rat encounters.

  17. Rat sightings in New York City are associated with neighborhood sociodemographics, housing characteristics, and proximity to open public space

    Directory of Open Access Journals (Sweden)

    Michael G. Walsh

    2014-08-01

    Full Text Available Rats are ubiquitous in urban environments and, as established reservoirs for infectious pathogens, present a control priority for public health agencies. New York City (NYC harbors one of the largest rat populations in the United States, but surprising little study has been undertaken to define rat ecology across varied features of this urban landscape. More importantly, factors that may contribute to increased encounters between rats and humans have rarely been explored. Using city-wide records of rat sightings reported to the NYC Department of Health and Mental Hygiene, this investigation sought to identify sociodemographic, housing, and physical landscape characteristics that are associated with increased rat sightings across NYC census tracts. A hierarchical Bayesian conditional autoregressive Poisson model was used to assess these associations while accounting for spatial heterogeneity in the variance. Closer proximity to both subway lines and recreational public spaces was associated with a higher concentration of rat sightings, as was a greater presence of older housing, vacant housing units, and low education among the population. Moreover, these aspects of the physical and social landscape accurately predicted rat sightings across the city. These findings have identified specific features of the NYC urban environment that may help to provide direct control targets for reducing human–rat encounters.

  18. Search Space Calculation to Improve Parameter Estimation of Excitation Control Systems

    Directory of Open Access Journals (Sweden)

    Andrés J. Saavedra-Montes

    2013-11-01

    Full Text Available A method to calculate the search space for each parameter in an excitation control system is presented in this paper. The calculated search space is intended to reduce the number of parameter solution sets that can be found by an estimation algorithm, reducing its processing time. The method considers a synchronous generator time constant range between 4s and 10s, an excitation control system performance index, a controller design technique, and the excitation control system model structure. When the obtained search space is used to estimate the parameters, less processing time is used by the algorithm. Also the estimated parameters are closer to the reference ones.

  19. Open-Rate Controlled Experiment in E-Mail Marketing Campaigns

    Directory of Open Access Journals (Sweden)

    Antun Biloš

    2016-06-01

    Full Text Available Purpose – The main purpose of this paper is to test the controlled experiment (A/B split methodology in B2C oriented e-mail marketing campaigns. Design/Methodology/Approach – E-mail marketing techniques have been a substantial part of e-marketing methodology since the early Internet days of the mid-1990s. From the very beginning of Internet utilization for business purposes, e-mail was one of the most widely used communication techniques in B2B and B2C markets alike. Due to high volumes of spamming and progression of online communication clutter, some practitioners began to question the usability of e-mail as a marketing communication channel, while others embarked on working on improving the message itself. Efforts were invested into improving message quality, as well as into better understanding user expectations. One of the most commonly used techniques to test specific e-mail message elements is the controlled experiment. Findings and implications – This paper explores several types of controlled experiments in a specific Croatian B2C market. Tests were run to determine subscriber behavior towards several newsletter components, including sending time, sending day, sender’s name, and subject line. Open and click rates for tested campaigns, and several other metrics were investigated using MailChimp software. An N − 1 two-proportion test using an adjusted Wald confidence interval around the difference in the proportions was used for comparing the open-rate measure in the controlled experiments between subjects. Limitation – Controlled experiments (A/B split tests showed a lot of potential as a way of measuring behavior and preferences of subscribers, although several apparent limitations (the data-set scope, comparability issues indicated a clear need for standardization on a managerial and scientific level. Originality – This paper provides an up-to-date e-mail marketing effectiveness literature review, describes and tests the

  20. Active Grasping Control of Virtual-Dexterous-Robot Hand with Open Inventor

    Directory of Open Access Journals (Sweden)

    Jinbao Chen

    2014-01-01

    Full Text Available The grasping technology of the virtual-dexterous-robot (VDR hand plays a key role in the teleoperation of the space robot. For a grasp task in the virtual environment, the collision detection and virtual force calculation need to be implemented. Firstly, a tree-structure virtual scene including a VDR hand and a target object is built up with open inventor (OIV. Secondly, the collision manager provided by OIV is used for collision detection and the oriented bounding box (OBB is adopted to improve the real-time performance of collision detection. Thirdly, an algorithm is proposed for calculating the virtual force by using the contact deformation. And the contact deformation is calculated according to the transformation matrix between the coordinate systems of the two contact objects. Furthermore, the contact friction is also calculated by this matrix. Considering the virtual force, the modified stable grasping conditions are proposed which are suitable for the virtual grasping. Then a method is proposed for implementing the grasp or release operation by translating different nodes in the tree-structure scene, which can avoid destroying the tree structure. Finally, the viability and effectiveness of the proposed algorithms are proved by simulation experiments.