An Adaptive Supervisory Sliding Fuzzy Cerebellar Model Articulation Controller for Sensorless Vector-Controlled Induction Motor Drive Systems

Directory of Open Access Journals (Sweden)

Shun-Yuan Wang

2015-03-01

Full Text Available This paper presents the implementation of an adaptive supervisory sliding fuzzy cerebellar model articulation controller (FCMAC in the speed sensorless vector control of an induction motor (IM drive system. The proposed adaptive supervisory sliding FCMAC comprised a supervisory controller, integral sliding surface, and an adaptive FCMAC. The integral sliding surface was employed to eliminate steady-state errors and enhance the responsiveness of the system. The adaptive FCMAC incorporated an FCMAC with a compensating controller to perform a desired control action. The proposed controller was derived using the Lyapunov approach, which guarantees learning-error convergence. The implementation of three intelligent control schemes—the adaptive supervisory sliding FCMAC, adaptive sliding FCMAC, and adaptive sliding CMAC—were experimentally investigated under various conditions in a realistic sensorless vector-controlled IM drive system. The root mean square error (RMSE was used as a performance index to evaluate the experimental results of each control scheme. The analysis results indicated that the proposed adaptive supervisory sliding FCMAC substantially improved the system performance compared with the other control schemes.

Plant Modeling for Human Supervisory Control

DEFF Research Database (Denmark)

Lind, Morten

1999-01-01

This paper provides an overview of multilevel flow modelling (MFM) and its application for design of displays for the supervisory control of industrial plant. The problem of designing the inforrrzatian content of sacpervisory displays is discussed and plant representations like MFM using levels...

Supervisory control synthesis for a waterway lock

NARCIS (Netherlands)

Reijnen, F.F.H.; Goorden, M.A.; van de Mortel - Fronczak, J.M.; Rooda, J.E.

2017-01-01

Formal methods help in coping with the growing functionality and complexity, time-to-market and costs in cyber-physical systems (CPSs). Supervisory control synthesis (SCS) is such a method. It can be used to synthesize a controller for a CPS from the uncontrolled system model (plant) and the

Supervisory Control and Diagnostics System Distributed Operating System

International Nuclear Information System (INIS)

McGoldrick, P.R.

1979-01-01

This paper contains a description of the Supervisory Control and Diagnostics System (SCDS) Distributed Operating System. The SCDS consists of nine 32-bit minicomputers with shared memory. The system's main purpose is to control a large Mirror Fusion Test Facility

Conceptual design of a new supervisory control system for JT-60SA

International Nuclear Information System (INIS)

Totsuka, Toshiyuki; Sakata, Shinya

2009-05-01

The functions of JT-60 discharge control computer system and the data processing computer system will be integrated into a new JT-60SA supervisory control system to improve the operational efficiency of the JT-60 control computer system. In this report, we first show the necessary requirements for the new JT-60SA supervisory control system that should have high cost performance and maintainability. Next, overall system image of the new JT-60SA supervisory control system is presented and the necessary functions and the issues to be solved in the development are shown. Finally, the necessary manpower for this development and performance of the computer hardware, and the expected reduction of maintenance cost of the computer system are described. (author)

Spatially Controlled Relay Beamforming

Science.gov (United States)

Kalogerias, Dionysios

This thesis is about fusion of optimal stochastic motion control and physical layer communications. Distributed, networked communication systems, such as relay beamforming networks (e.g., Amplify & Forward (AF)), are typically designed without explicitly considering how the positions of the respective nodes might affect the quality of the communication. Optimum placement of network nodes, which could potentially improve the quality of the communication, is not typically considered. However, in most practical settings in physical layer communications, such as relay beamforming, the Channel State Information (CSI) observed by each node, per channel use, although it might be (modeled as) random, it is both spatially and temporally correlated. It is, therefore, reasonable to ask if and how the performance of the system could be improved by (predictively) controlling the positions of the network nodes (e.g., the relays), based on causal side (CSI) information, and exploitting the spatiotemporal dependencies of the wireless medium. In this work, we address this problem in the context of AF relay beamforming networks. This novel, cyber-physical system approach to relay beamforming is termed as "Spatially Controlled Relay Beamforming". First, we discuss wireless channel modeling, however, in a rigorous, Bayesian framework. Experimentally accurate and, at the same time, technically precise channel modeling is absolutely essential for designing and analyzing spatially controlled communication systems. In this work, we are interested in two distinct spatiotemporal statistical models, for describing the behavior of the log-scale magnitude of the wireless channel: 1. Stationary Gaussian Fields: In this case, the channel is assumed to evolve as a stationary, Gaussian stochastic field in continuous space and discrete time (say, for instance, time slots). Under such assumptions, spatial and temporal statistical interactions are determined by a set of time and space invariant

Supervisory control system implemented in programmable logical controller web server

OpenAIRE

Milavec, Simon

2012-01-01

In this thesis, we study the feasibility of supervisory control and data acquisition (SCADA) system realisation in a web server of a programmable logic controller. With the introduction of Ethernet protocol to the area of process control, the more powerful programmable logic controllers obtained integrated web servers. The web server of a programmable logic controller, produced by Siemens, will also be described in this thesis. Firstly, the software and the hardware equipment used for real...

A Process Algebra for Supervisory Coordination

Directory of Open Access Journals (Sweden)

Jos Baeten

2011-08-01

Full Text Available A supervisory controller controls and coordinates the behavior of different components of a complex machine by observing their discrete behaviour. Supervisory control theory studies automated synthesis of controller models, known as supervisors, based on formal models of the machine components and a formalization of the requirements. Subsequently, code generation can be used to implement this supervisor in software, on a PLC, or embedded microprocessor. In this article, we take a closer look at the control loop that couples the supervisory controller and the machine. We model both event-based and state-based observations using process algebra and bisimulation-based semantics. The main application area of supervisory control that we consider is coordination, referred to as supervisory coordination, and we give an academic and an industrial example, discussing the process-theoretic concepts employed.

Supervisory control of drilling of composite materials

Science.gov (United States)

Ozaki, Motoyoshi

Composite materials have attractive features, such as high ratios of strength-to-weight and stiffness-to-weight. However, they are easily damaged when they are machined. A typical damage is delamination, which can occur when fiber reinforced composite laminates are drilled. The objective of this research is to study the drilling processes of carbon fiber reinforced laminates, and to develop and test a supervisory control strategy for their delamination-free drilling. Characterization of thrust force and torque is achieved through constant feedrate drilling experiments. The average values of thrust force and torque during the full engagement of the drill are utilized to obtain the Shaw's equations' parameters. The thrust force profile just before exit is given special attention. The Hocheng-Dharan equations, which give conservative values of delamination at the entrance and at the exit, are modified to express the influence of one lamina thickness explicitly. They are utilized not only for the characterization of thrust force but also for the determination of the thrust force reference for force control. In the design of the controllers of thrust force and torque, both thrust force and torque are assumed to be proportional to FPHR (Feed Per Half Revolution). A discrete-time dynamic model is established for the case when the time interval for a half revolution of the drill is divided by the sampling time, and the model is extended to the case of general spindle speeds. PI controllers are designed for the dynamic models of thrust force and torque. Root-locus techniques are used in the analysis. The phases of the drilling process are introduced and the control strategy at each phase is explained. The supervisory controller chooses not only the best control strategy for each phase, but also the reference value and the controller gain that are suitable at each drill position. Drilling experiments are conducted to show the usefulness of the concepts introduced in this

Supervisory control software for MFTF neutral beams

International Nuclear Information System (INIS)

Woodruff, J.P.

1981-01-01

We describe the software structures that control the operation of MFTF Sustaining Neutral Beam Power Supplies (SNBPS). These components of the Supervisory Control and Diagnostics System (SCDS) comprise ten distinct tasks that exist in the SCDS system environment. The codes total about 16,000 lines of commented Pascal code and occupy 240 kbytes of memory. The controls have been running since March 1981, and at this writing are being integrated to the Local Control System and to the power supply Pulse Power Module Controller

Design of Multiregional Supervisory Fuzzy PID Control of pH Reactors

Directory of Open Access Journals (Sweden)

Shebel AlSabbah

2015-01-01

Full Text Available This work concerns designing multiregional supervisory fuzzy PID (Proportional-Integral-Derivative control for pH reactors. The proposed work focuses, mainly, on two themes. The first one is to propose a multiregional supervisory fuzzy-based cascade control structure. It would enable modifying dynamics and enhance system’s stability. The fuzzy system (master loop has been chosen as a tuner for PID controller (slave loop. It takes into consideration parameters uncertainties and reference tracking. The second theme concerns designing a hybrid neural network-based pH estimator. The proposed estimator would overcome the industrial drawbacks, that is, cost and size, found with conventional methods for pH measurement. The final end-user-interface (EUI front panel and the results that evaluate the performance of the supervisory fuzzy PID-based control system and hybrid NN-based estimator have been presented using the compatibility found between LabView and MatLab. They lead to conclude that the proposed algorithms are appropriate to systems nonlinearities encountered with pH reactors.

A distributed hierarchical architecture of expert systems for supervisory control of multimodular nuclear reactors

International Nuclear Information System (INIS)

Otaduy, P.J.; Brittain, C.R.; Rovere, L.A.; Gove, N.B.

1991-01-01

A hierarchical supervisory control architecture has being implemented at ORNL to coordinate the controllers of a multimodular nuclear plant. The supervisory controller form a network of distributed expert system interfaced with a real-time simulation of the plant, the plant's automatic controllers, and the human operator. The main goal of the supervisory controllers is to maintain the plant operating within safety envelopes while optimizing availability, minimizing stress to components and operators, and facilitating operations. Representative rules implementing strategies for situation dependent reassignment of process goals by embedding diagnostics into the control philosophy are discussed. It should noted that the control philosophies here described use the ALMR concept for illustration purposes and are not part of the official ALMR design at this time. 3 refs., 1 fig

Predictive Models of Procedural Human Supervisory Control Behavior

Science.gov (United States)

2011-01-01

821708, Brest , France. Page 139 of 150 Boussemart, Y. and M. L. Cummings (2010). "Predicting Supervisory Control Behavior with Hidden Markov Models...Strategies for Strike Planning. COGIS 2006 - Cognitive Systems with Interactive Sensors, Paris . Burges, C. (1998). "A Tutorial on Support Vector Machines

Discrete Event Supervisory Control Applied to Propulsion Systems

Science.gov (United States)

Litt, Jonathan S.; Shah, Neerav

2005-01-01

The theory of discrete event supervisory (DES) control was applied to the optimal control of a twin-engine aircraft propulsion system and demonstrated in a simulation. The supervisory control, which is implemented as a finite-state automaton, oversees the behavior of a system and manages it in such a way that it maximizes a performance criterion, similar to a traditional optimal control problem. DES controllers can be nested such that a high-level controller supervises multiple lower level controllers. This structure can be expanded to control huge, complex systems, providing optimal performance and increasing autonomy with each additional level. The DES control strategy for propulsion systems was validated using a distributed testbed consisting of multiple computers--each representing a module of the overall propulsion system--to simulate real-time hardware-in-the-loop testing. In the first experiment, DES control was applied to the operation of a nonlinear simulation of a turbofan engine (running in closed loop using its own feedback controller) to minimize engine structural damage caused by a combination of thermal and structural loads. This enables increased on-wing time for the engine through better management of the engine-component life usage. Thus, the engine-level DES acts as a life-extending controller through its interaction with and manipulation of the engine s operation.

The role of supervisory controller synthesis in automatic control software development

NARCIS (Netherlands)

Baeten, J.C.M.; Markovski, J.

2015-01-01

We give an overview of a model-driven systems engineering approach for high-tech systems that relies on supervisory controller synthesis. The proposed framework has a process-theoretic foundation and supports extensions with quantitative features. We briefly discuss several industrial case studies

International Symposium on Monitoring Behavior and Supervisory Control

CERN Document Server

Johannsen, Gunnar

1976-01-01

This book includes all papers presented at the International Symposium on Monitoring Behavior and Supervisory Control held at Berchtesgaden, Federal Republic of Germany, March 8-12, 1976. The Symposium was sponsored by the Scientific Affairs Division of the North Atlantic Treaty Organization, Brussels, and the government of the Federal Republic of Germany, Bonn. We believe the book constitutes an important and timely status report on monitoring behavior and supervisory control by human operators of complex man-machine systems in which the computer is sharing key functions with the man. These systems include aircraft and other vehicles, nuclear and more conventional power plants, and processes for the manu­ facture of chemicals, petroleum, and discrete parts. By "monitoring" we mean the systematic observation by a human operator of mul tiple sources of information, e. g. , ranging from integrated display consoles to disparate "live situations". The monitor's purpose is to determine whether operations are norm...

Process theory for supervisory control of stochastic systems with data

NARCIS (Netherlands)

Markovski, J.

2012-01-01

We propose a process theory for supervisory control of stochastic nondeterministic plants with data-based observations. The Markovian process theory with data relies on the notion of Markovian partial bisimulation to capture controllability of stochastic nondeterministic systems. It presents a

Self-oscillations in dynamic systems a new methodology via two-relay controllers

CERN Document Server

Aguilar, Luis T; Fridman, Leonid; Iriarte, Rafael

2015-01-01

This monograph presents a simple and efficient two-relay control algorithm for generation of self-excited oscillations of a desired amplitude and frequency in dynamic systems. Developed by the authors, the two-relay controller consists of two relays switched by the feedback received from a linear or nonlinear system, and represents a new approach to the self-generation of periodic motions in underactuated mechanical systems. The first part of the book explains the design procedures for two-relay control using three different methodologies – the describing-function method, Poincaré maps, and the locus-of-a perturbed-relay-system method – and concludes with stability analysis of designed periodic oscillations. Two methods to ensure the robustness of two-relay control algorithms are explored in the second part, one based on the combination of the high-order sliding mode controller and backstepping, and the other on higher-order sliding-modes-based reconstruction of uncertainties and their compensation where...

Decision support in supervisory control

International Nuclear Information System (INIS)

Rasmussen, J.; Goodstein, L.P.

1985-08-01

It is argued that the supervisory control of complex industrial processes having a potential for serious consequences in case of accidents requires careful consideration of the allocation of decision making between the three main agents of control; namely the designer, the operator and the automatic control system. In particular, it is advocated that instead of continuing their efforts to make their preplanning of responses and countermeasures more and more complete and restricting the operator's initiative, designers should take advantage of modern information technology to make available to the operators their conceptual models and their processing resources so as to allow the operators to function as their extended arm in coping with the plant. Such an interactive decision making activity would thus benefit from this simultaneous availability of the design basis, up-to-date knowledge of plant status and accumualted operational experience. (author)

Supervisory control of (max,+) automata: extensions towards applications

Czech Academy of Sciences Publication Activity Database

Lahaye, S.; Komenda, Jan; Boimond, J.-L.

2015-01-01

Roč. 88, č. 12 (2015), s. 2523-2537 ISSN 0020-7179 Institutional support: RVO:67985840 Keywords : discrete event systems * logical and timed behaviors * (max,+) automata * supervisory control Subject RIV: BA - General Mathematics Impact factor: 1.880, year: 2015 http://www.tandfonline.com/doi/full/10.1080/00207179.2015.1048295

Supervisory control of (max,+) automata: extensions towards applications

Czech Academy of Sciences Publication Activity Database

Lahaye, S.; Komenda, Jan; Boimond, J.-L.

2015-01-01

Roč. 88, č. 12 (2015), s. 2523-2537 ISSN 0020-7179 Institutional support: RVO:67985840 Keywords : discrete event systems * logical and time d behaviors * (max,+) automata * supervisory control Subject RIV: BA - General Mathematics Impact factor: 1.880, year: 2015 http://www.tandfonline.com/doi/full/10.1080/00207179.2015.1048295

Distributed stability control using intelligent voltage-margin relay

Energy Technology Data Exchange (ETDEWEB)

Wiszniewski, A.; Rebizant, W. [Wroclaw Univ. of Technology (Poland); Klimek, A. [Powertech Labs Inc., Surrey, BC (Canada)

2010-07-01

This paper presented an intelligent relay that operates if the load to source impedance ratio decreases to a level that is dangerously close to the stability limit, which leads to power system blackouts. The intelligent voltage-margin/difference relay installed at receiving substations automatically initiates action if the voltage stability margin drops to a dangerously low level. The relay decides if the tap changing devices are to be blocked and if under-voltage load shedding should be initiated, thereby mitigating an evolving instability. The intelligent relay has two levels of operation. At the first stage, which corresponds to the higher load to source impedance ratio, the relay initiates blocking of the tap changer. At the second stage, corresponding to the lower source to load impedance ratio, load shedding is initiated. The relay operates when the load to source impedance ratio reaches a certain predetermined level, but it does not depend either on the level of the source voltage or on the difference of source and load impedance phase angles. The algorithm for the relay is relatively simple and uses only locally available signals. Consequently, the transformer is well controlled to eliminate the cases of voltage instability. 6 refs., 7 figs.

Supervisory Control of (max,+) automata: a behavioral approach

Czech Academy of Sciences Publication Activity Database

Komenda, Jan; Lahaye, S.; Boimond, J.-L.

2009-01-01

Roč. 19, č. 4 (2009), s. 525-549 ISSN 0924-6703 Grant - others:EU Projekt(XE) EU.ICT.DISC 224498 Institutional research plan: CEZ:AV0Z10190503 Keywords : timed discrete-event systems * supervisory control * formal power series * (max,+) * automata Subject RIV: BA - General Mathematics Impact factor: 0.921, year: 2009

Complexity of verifying nonblockingness in modular supervisory control

Czech Academy of Sciences Publication Activity Database

Masopust, Tomáš

2018-01-01

Roč. 63, č. 2 (2018), s. 602-607 ISSN 0018-9286 Institutional support: RVO:67985840 Keywords : nonblockingness * modular supervisory control * complexity Subject RIV: BA - General Mathematics OBOR OECD: Computer sciences, information science, bioinformathics (hardware development to be 2.2, social aspect to be 5.8) Impact factor: 4.270, year: 2016 http://ieeexplore.ieee.org/document/7979596/

Behavior coordination of mobile robotics using supervisory control of fuzzy discrete event systems.

Science.gov (United States)

Jayasiri, Awantha; Mann, George K I; Gosine, Raymond G

2011-10-01

In order to incorporate the uncertainty and impreciseness present in real-world event-driven asynchronous systems, fuzzy discrete event systems (DESs) (FDESs) have been proposed as an extension to crisp DESs. In this paper, first, we propose an extension to the supervisory control theory of FDES by redefining fuzzy controllable and uncontrollable events. The proposed supervisor is capable of enabling feasible uncontrollable and controllable events with different possibilities. Then, the extended supervisory control framework of FDES is employed to model and control several navigational tasks of a mobile robot using the behavior-based approach. The robot has limited sensory capabilities, and the navigations have been performed in several unmodeled environments. The reactive and deliberative behaviors of the mobile robotic system are weighted through fuzzy uncontrollable and controllable events, respectively. By employing the proposed supervisory controller, a command-fusion-type behavior coordination is achieved. The observability of fuzzy events is incorporated to represent the sensory imprecision. As a systematic analysis of the system, a fuzzy-state-based controllability measure is introduced. The approach is implemented in both simulation and real time. A performance evaluation is performed to quantitatively estimate the validity of the proposed approach over its counterparts.

Review of Supervisory Control and Data Acquisition (SCADA) Systems

Energy Technology Data Exchange (ETDEWEB)

Reva Nickelson; Briam Johnson; Ken Barnes

2004-01-01

A review using open source information was performed to obtain data related to Supervisory Control and Data Acquisition (SCADA) systems used to supervise and control domestic electric power generation, transmission, and distribution. This report provides the technical details for the types of systems used, system disposal, cyber and physical security measures, network connections, and a gap analysis of SCADA security holes.

Application of optimal control principles to describe the supervisory control behavior of AAA crew members

Science.gov (United States)

Hale, C.; Valentino, G. J.

1982-01-01

Supervisory decision making and control behavior within a C(3) oriented, ground based weapon system is being studied. The program involves empirical investigation of the sequence of control strategies used during engagement of aircraft targets. An engagement is conceptually divided into several stages which include initial information processing activity, tracking, and ongoing adaptive control decisions. Following a brief description of model parameters, two experiments which served as initial investigation into the accuracy of assumptions regarding the importance of situation assessment in procedure selection are outlined. Preliminary analysis of the results upheld the validity of the assumptions regarding strategic information processing and cue-criterion relationship learning. These results indicate that this model structure should be useful in studies of supervisory decision behavior.

Communicating Processes with Data for Supervisory Coordination

Directory of Open Access Journals (Sweden)

Jasen Markovski

2012-08-01

Full Text Available We employ supervisory controllers to safely coordinate high-level discrete(-event behavior of distributed components of complex systems. Supervisory controllers observe discrete-event system behavior, make a decision on allowed activities, and communicate the control signals to the involved parties. Models of the supervisory controllers can be automatically synthesized based on formal models of the system components and a formalization of the safe coordination (control requirements. Based on the obtained models, code generation can be used to implement the supervisory controllers in software, on a PLC, or an embedded (microprocessor. In this article, we develop a process theory with data that supports a model-based systems engineering framework for supervisory coordination. We employ communication to distinguish between the different flows of information, i.e., observation and supervision, whereas we employ data to specify the coordination requirements more compactly, and to increase the expressivity of the framework. To illustrate the framework, we remodel an industrial case study involving coordination of maintenance procedures of a printing process of a high-tech Oce printer.

Synthesis of relay control systems for nuclear reactors

International Nuclear Information System (INIS)

Postnikov, N.S.

1996-01-01

The problem on stabilizing an oscillatory-unstable reactor by a single-link relay system, the characteristics whereof have a dead zone and hysteresis loop, is considered. The methodology of synthesis of feedback law, providing for stochastic steady-state mode of reactor operation with the minimum frequency of control impact introduction is proposed. This methodology is applicable to general-type relay systems with arbitrary oscillatory-unstable objects. 6 refs., 5 figs

Two-objective on-line optimization of supervisory control strategy

Energy Technology Data Exchange (ETDEWEB)

Nassif, N.; Kajl, S.; Sabourin, R. [Ecole de Technologie Superieure, Montreal (Canada)

2004-09-01

The set points of supervisory control strategy are optimized with respect to energy use and thermal comfort for existing HVAC systems. The set point values of zone temperatures, supply duct static pressure, and supply air temperature are the problem variables, while energy use and thermal comfort are the objective functions. The HVAC system model includes all the individual component models developed and validated against the monitored data of an existing VAV system. It serves to calculate energy use during the optimization process, whereas the actual energy use is determined by using monitoring data and the appropriate validated component models. A comparison, done for one summer week, of actual and optimal energy use shows that the on-line implementation of a genetic algorithm optimization program to determine the optimal set points of supervisory control strategy could save energy by 19.5%, while satisfying the minimum zone airflow rates and the thermal comfort. The results also indicate that the application of the two-objective optimization problem can help control daily energy use or daily building thermal comfort, thus saving more energy than the application of the one-objective optimization problem. (Author)

Supervisory Control and Data Acquisition Laboratory

Directory of Open Access Journals (Sweden)

M. Iacob

2010-06-01

Full Text Available This paper presents practical laboratories for teaching purpose in Supervisory Control and Data Acquisition (SCADA systems. A SCADA system is described in terms of architecture, process interfaces, functionality, and application development facilities. These concepts are implemented on an integrated automation system, particularly for digital control of electric drives with a distributed peripheral, i.e., Totally Integrated Automation with Democase from Siemens. Using this system, a wide range of applications can be designed, implemented and tested. A practical labs set is presented to introduce gradually the main SCADA elements, and finally to develop an application to control an induction motor in interlocked manual/automatic mode, with touch-screen Human Machine Interface (HMI. The system employs industrial busses like PROFIBus and industrial Ethernet. The SCADA system also shows trends, alarms, motor frequency and automatic sequence of motor speed profile.

Framework for modeling supervisory control behavior of operators of nuclear power plants

International Nuclear Information System (INIS)

Baron, S.; Feehrer, C.; Muralidharan, R.; Pew, R.; Horwitz, P.

1982-01-01

The importance of modeling the human-machine system has long been recognized, and many attempts have been made to estimate the operator's effect on system performance and reliability. The development of reliability models has been aimed at providing the means for exploring the physical consequences of specific classes of human error. However, the total impact of human performance on system operation and the adequacy of existing design and operating standards cannot be adequatly captured or assessed by simple error probabilities, or even by the combination of such probabilities. The behaviors of relevance are supervisory in nature, with a substantial cognitive component. The broad requirements for a model of human supervisory control are extensive and suggest that a highly sophisticated computer model will be needed. The purpose of this paper is to provide a brief overview of the approach employed in developing such supervisory control models; of some proposed specializations and extensions to adapt them for the nuclear power plant case; and of the potential utility of such a model

Auditory decision aiding in supervisory control of multiple unmanned aerial vehicles.

Science.gov (United States)

Donmez, Birsen; Cummings, M L; Graham, Hudson D

2009-10-01

This article is an investigation of the effectiveness of sonifications, which are continuous auditory alerts mapped to the state of a monitored task, in supporting unmanned aerial vehicle (UAV) supervisory control. UAV supervisory control requires monitoring a UAV across multiple tasks (e.g., course maintenance) via a predominantly visual display, which currently is supported with discrete auditory alerts. Sonification has been shown to enhance monitoring performance in domains such as anesthesiology by allowing an operator to immediately determine an entity's (e.g., patient) current and projected states, and is a promising alternative to discrete alerts in UAV control. However, minimal research compares sonification to discrete alerts, and no research assesses the effectiveness of sonification for monitoring multiple entities (e.g., multiple UAVs). The authors conducted an experiment with 39 military personnel, using a simulated setup. Participants controlled single and multiple UAVs and received sonifications or discrete alerts based on UAV course deviations and late target arrivals. Regardless of the number of UAVs supervised, the course deviation sonification resulted in reactions to course deviations that were 1.9 s faster, a 19% enhancement, compared with discrete alerts. However, course deviation sonifications interfered with the effectiveness of discrete late arrival alerts in general and with operator responses to late arrivals when supervising multiple vehicles. Sonifications can outperform discrete alerts when designed to aid operators to predict future states of monitored tasks. However, sonifications may mask other auditory alerts and interfere with other monitoring tasks that require divided attention. This research has implications for supervisory control display design.

The Davros III supervisory control system

International Nuclear Information System (INIS)

Rice, P.

1996-01-01

Magnox Electric's Remote Operations Branch deploy a wide variety of remote inspection and maintenance tools into nuclear plant in order to perform a variety of tasks. In recent years much progress has been made on low-level control of individual manipulator axes, and a parallel need has emerged for a supervisory system to assist the operator in the control of the whole system. Some requirements are: 1) to improve operator control of systems; 2) to simplify software maintenance and version control; 3) to reduce the likelihood of damage to manipulators; 4) to assist with rehearsals and simulations. Davros III is a PC software system which has been developed over a number of years to address these requirements. In a single program capable of being configured for a wide variety of applications, it provides a technique for following pretaught routes, a comprehensive and fully configurable interlock system and several different facilities for simulation. (author)

The Davros III supervisory control system

International Nuclear Information System (INIS)

Rice, P.

1996-01-01

Magnox Electric's Remote Operations Bbranch deploy a wide variety of remote inspection and maintenance tools into nuclear plant in order to perform a variety of tasks. In recent years much progress has been made on low-level control of individual manipulator axes and a parallel need has emerged for a supervisory system to assist the operator in the control of the whole system. Some requirements are: 1, To improve operator control of systems. 2, To simplify software maintenance and version control. 3, To reduce the likelihood of damage to manipulators. 4, To assist with rehearsals and simulations. Davros III is a PC software system which has been developed over a number of years to address these requirements. In a single program capable of being configured for a wide variety of applications, it provides a technique for following pretaught routes, a comprehensive and fully configurable interlock system and several different facilities for simulation. (author)

Model-based design of supervisory controllers for baggage handling systems

NARCIS (Netherlands)

Swartjes, L.; van Beek, D.A.; Fokkink, W.J.; van Eekelen, J.A.W.M.

2017-01-01

The complexity of airport baggage handling systems in combination with the required high level of robustness makes designing supervisory controllers for these systems a challenging task. We show how a state of the art, formal, model-based design framework has been successfully used for model-based

Hierarchical Discrete Event Supervisory Control of Aircraft Propulsion Systems

Science.gov (United States)

Yasar, Murat; Tolani, Devendra; Ray, Asok; Shah, Neerav; Litt, Jonathan S.

2004-01-01

This paper presents a hierarchical application of Discrete Event Supervisory (DES) control theory for intelligent decision and control of a twin-engine aircraft propulsion system. A dual layer hierarchical DES controller is designed to supervise and coordinate the operation of two engines of the propulsion system. The two engines are individually controlled to achieve enhanced performance and reliability, necessary for fulfilling the mission objectives. Each engine is operated under a continuously varying control system that maintains the specified performance and a local discrete-event supervisor for condition monitoring and life extending control. A global upper level DES controller is designed for load balancing and overall health management of the propulsion system.

Supervisory Control Strategy Development

International Nuclear Information System (INIS)

Gary D Storrick; Bojan Petrovic

2007-01-01

Task 4 of this collaborative effort between ORNL, Brazil, and Westinghouse for the International Nuclear Energy Research Initiative entitled 'Development of Advanced Instrumentation and Control for an Integrated Primary System Reactor' focused on the design of the hierarchical supervisory control for multiple-module units. The state of the IRIS plant design--specifically, the lack of a detailed secondary system design--made developing a detailed hierarchical control difficult at this time. However, other simultaneous and ongoing efforts have contributed to providing the needed information. This report summarizes the results achieved under Task 4 of this Financial Assistance Award. Section 1.2 describes the scope of this effort. Section 2 discusses the IRIS control functions. Next, it briefly reviews the current control concepts, and then reviews the maneuvering requirements for the IRIS plant. It closes by noting the benefits that automated sequences have in reducing operator workload. Section 3 examines reactor loading in the frequency domain to establish some guidelines for module operation, paying particular attention to strategies for using process steam for desalination and/or district heating. The final subsection discusses the implications for reactor control, and argues that using the envisioned percentage (up to 10%) of the NSSS thermal output for these purposes should not significantly affect the NSSS control strategies. Section 4 uses some very general economic assumptions to suggest how one should approach multi-module operation. It concludes that the well-known algorithms used for economic dispatching could be used to help manage a multi-unit IRIS site. Section 5 addresses the human performance factors of multi-module operation. Section 6 summarizes our conclusions

Extended supervisory control of Peirce-Smith converter

International Nuclear Information System (INIS)

Hadjiski, Mincho; Boshnakov, Kosta

2014-01-01

In this paper some problems of the tight integration of the Process Control (PC) and Condition Based Maintenance (CBM) are considered in the creation of a supervised control system for Peirce-Smith Converter. The motivation of this approach is carried out on the base of numerous experimental data analyses, which show a significant improving potential. Because of a very high level of stochastic components in the direct measurements, due to the melt crystallisation a data driven degradation model is derived. A multistage procedure is proposed for effective Maintenance Decision Making (MDM) using a threshold based policy, Rule-Based Reasoning (RBR) and Case-Based Reasoning (CBR). The extended functionality of the proposed system is discussed. Key words: mathematical modelling, Peirce-Smith converter (PSC), rule-based reasoning (RBR), supervisory control, threshold based maintenance, maintenance decision making

Supervisory fussy control for an electric generating hybrid system; Control supervisorio difuso para un sistema hibrido de generacion electrica

Energy Technology Data Exchange (ETDEWEB)

Lagunas Mendoza, Javier

2004-11-15

This work presents the development of a fuzzy supervisory controller for a hybrid power system (HPS). After reviewing the actual configurations for Hybrid Systems used around the world, it was defined the configuration and constitutive elements to be implemented in proposed HPS. The HPS includes: photovoltaic arrays, wind turbines as renewable sources, a Gen-set as a back-up system, a battery bank a mean for energy storage, AC loads and finally an inverter to transform DC to AC in order to provide electricity to the loads. Once the HPS configuration was selected, the mathematical models for the different elements of the system were selected. The validation of the models was made comparing the results from the model with collected real data of an experimental HPS installed in Pachuca Hidalgo. Using MatLab it was developed a program to simulate the operation of the a HPS. The main function of the supervisory controller within the HPS is to satisfy the objectives of operation of the system, and it was defined as part of the research work. The operation philosophy of the supervisory controller was defined having selected HPS configuration and the operation objectives of the system. Regarding to the supervisory controller development, first it was carried out a bibliographic review of the supervisory controllers that are used nowadays whose use some techniques of intelligent control. As result form this review the fuzzy logic technique was chosen to be implemented in the supervisory controller proposed. The resulting supervisory controller was a multi- variable system type, and it is implementation was challenging task. Its development was made using the hierarchic decomposition based on meta-knowledge. As result a smaller diffuse systems with a less number of rules were obtained. An important part of the work was the implementation of the supervisory controller in Matlab. The controller tested in the developed simulation program for SHGE. The results of operation of

Evaluating the Impact of Communication Network Performance on Supervisory Supermarket Control

DEFF Research Database (Denmark)

Madsen, Jacob Theilgaard; Minko, Tomasz; Madsen, Tatiana Kozlova

2017-01-01

This paper addresses the evaluation of the impact of non-ideal communication networks on system performance of hierarchical control systems. It develops a stepwise evaluation approach that is applied to the example scenario of a supervisory controller for supermarket temperature control, addressing...... of communication network performance on the supermarket refrigeration control and resulting energy costs using simulation models. The results show that the controller is resilient to downstream information delays, however upstream delays or up- and downstream information loss can cause significant performance...

Developing operator capacity estimates for supervisory control of autonomous vehicles.

Science.gov (United States)

Cummings, M L; Guerlain, Stephanie

2007-02-01

This study examined operators' capacity to successfully reallocate highly autonomous in-flight missiles to time-sensitive targets while performing secondary tasks of varying complexity. Regardless of the level of autonomy for unmanned systems, humans will be necessarily involved in the mission planning, higher level operation, and contingency interventions, otherwise known as human supervisory control. As a result, more research is needed that addresses the impact of dynamic decision support systems that support rapid planning and replanning in time-pressured scenarios, particularly on operator workload. A dual screen simulation that allows a single operator the ability to monitor and control 8, 12, or 16 missiles through high level replanning was tested on 42 U.S. Navy personnel. The most significant finding was that when attempting to control 16 missiles, participants' performance on three separate objective performance metrics and their situation awareness were significantly degraded. These results mirror studies of air traffic control that demonstrate a similar decline in performance for controllers managing 17 aircraft as compared with those managing only 10 to 11 aircraft. Moreover, the results suggest that a 70% utilization (percentage busy time) score is a valid threshold for predicting significant performance decay and could be a generalizable metric that can aid in manning predictions. This research is relevant to human supervisory control of networked military and commercial unmanned vehicles in the air, on the ground, and on and under the water.

Operational Performance Risk Assessment in Support of A Supervisory Control System

Energy Technology Data Exchange (ETDEWEB)

Denning, Richard S. [Self Employed; Muhlheim, Michael David [ORNL; Cetiner, Sacit M. [ORNL; Guler Yigitoglu, Askin [ORNL

2017-06-01

Supervisory control system (SCS) is developed for multi-unit advanced small modular reactors to minimize human interventions in both normal and abnormal operations. In SCS, control action decisions made based on probabilistic risk assessment approach via Event Trees/Fault Trees. Although traditional PRA tools are implemented, their scope is extended to normal operations and application is reversed; success of non-safety related system instead failure of safety systems this extended PRA approach called as operational performance risk assessment (OPRA). OPRA helps to identify success paths, combination of control actions for transients and to quantify these success paths to provide possible actions without activating plant protection system. In this paper, a case study of the OPRA in supervisory control system is demonstrated within the context of the ALMR PRISM design, specifically power conversion system. The scenario investigated involved a condition that the feed water control valve is observed to be drifting to the closed position. Alternative plant configurations were identified via OPRA that would allow the plant to continue to operate at full or reduced power. Dynamic analyses were performed with a thermal-hydraulic model of the ALMR PRISM system using Modelica to evaluate remained safety margins. Successful recovery paths for the selected scenario are identified and quantified via SCS.

National Ignition Facility subsystem design requirements supervisory control software SSDR 1.5.2

International Nuclear Information System (INIS)

Woodruff, J.; VanArsdall, P.; Bliss, E.

1996-01-01

This System Design Requirement document establishes the performance, design, development, and test requirements for the Supervisory Control Software, WBS 1.5.2, which is part of the NIF Integrated Computer Control System (ICCS). This document responds directly to the requirements detailed in ICCS (WBS 1-5)

Supervisory control synthesis of discrete-event systems using a coordination scheme

Czech Academy of Sciences Publication Activity Database

Komenda, Jan; Masopust, Tomáš; van Schuppen, J. H.

2012-01-01

Roč. 48, č. 2 (2012), s. 247-254 ISSN 0005-1098 R&D Projects: GA ČR(CZ) GAP103/11/0517; GA ČR GPP202/11/P028 Grant - others:European Commission(XE) EU.ICT.DISC 224498 Institutional research plan: CEZ:AV0Z10190503 Keywords : discrete-event systems * supervisory control * distributed control * closed-loop systems * controllability Subject RIV: BA - General Mathematics Impact factor: 2.919, year: 2012 http://www.sciencedirect.com/science/article/pii/S0005109811005395

Supervisory control synthesis of discrete-event systems using a coordination scheme

Czech Academy of Sciences Publication Activity Database

Komenda, Jan; Masopust, Tomáš; van Schuppen, J. H.

2012-01-01

Roč. 48, č. 2 (2012), s. 247-254 ISSN 0005-1098 R&D Projects: GA ČR(CZ) GAP103/11/0517; GA ČR GPP202/11/P028 Grant - others:European Commission(XE) EU. ICT .DISC 224498 Institutional research plan: CEZ:AV0Z10190503 Keywords : discrete-event systems * supervisory control * distributed control * closed-loop systems * controllability Subject RIV: BA - General Mathematics Impact factor: 2.919, year: 2012 http://www.sciencedirect.com/science/article/pii/S0005109811005395

Assistance tools for generic definition of ITER maintenance tasks and scenarios in advanced supervisory control systems

International Nuclear Information System (INIS)

Zieba, Stéphane; Russotto, François-Xavier; Da Silva Simoes, Max; Measson, Yvan

2013-01-01

Highlights: ► Improve supervisory control systems for ITER in-vessel and hot cell maintenance. ► Optimize remote handling operations effectiveness, reliability and safety. ► Provide a generic description of the maintenance tasks and scenarios. ► Development of context-based assistances for operators and supervisor. ► Improvement of operator's situation awareness. -- Abstract: This paper concerns the improvement of supervisory control systems in the context of remote handling for the maintenance tasks in ITER. This work aims at providing a single formalism and tools to define in a generic way the ITER maintenance tasks and scenarios for in-vessel and hot cell operations. A three-layered approach is proposed to model these tasks and scenarios. Physical actions are defined for the scene elements. From these physical actions, behaviours are defined to represent high-level functionalities. Finally, interaction modes define the way that behaviours are achieved in terms of human–machine interactions. Case study concerning the blanket maintenance procedure is discussed concerning the contributions of the descriptive model and the context-based assistances to the activities of supervisory control

A test system and supervisory control and data acquisition application with programmable logic controller for thermoelectric generators

International Nuclear Information System (INIS)

Ahiska, Rasit; Mamur, Hayati

2012-01-01

Highlights: ► A new TEG test measurement system with the PLC has been carried out. ► A new SCADA program has been written and tested for the test measurement system. ► An operator panel has been used for monitoring to the instant TEG data. ► All of the measurement data of TEG have been aggregated in the system. - Abstract: In this study, a new test measurement system and supervisory control and data acquisition application with programmable logic controller has been carried out to be enable the collection of the data of thermoelectric generator for the usage of thermoelectric modules as thermoelectric generator. During the production of the electric energy from the thermoelectric generator, the temperatures of the surfaces of the thermoelectric generator, current–voltage values obtained from output of the thermoelectric generator, hot and cold flows have been measured by the newly established system instantly. All these data have been monitored continuously from the computer and recorded by a supervisory control and data acquisition program. At the same time, in environments where there was no computer, an operator panel with the ability to communicate with the programmable logic controller has been added for the monitoring of the instant thermoelectric generator data. All of the measurement data of the thermoelectric generator have been aggregated in the new test measurement and supervisory control and data acquisition system. The setup test measurement system has been implemented on the thermoelectric generator system with about 10 W. Thermoelectric generators, Altec-GM-1 brand-coded have been examined by the new proposed test measurement system and the values of maximum power and thermoelectric generator efficiency were calculated by the programmable logic controller. When the obtained results were compared with the datasheets, the relative error for the maximum power was around 4% and the value for efficiency was below 3%.

Model-based iterative learning control of Parkinsonian state in thalamic relay neuron

Science.gov (United States)

Liu, Chen; Wang, Jiang; Li, Huiyan; Xue, Zhiqin; Deng, Bin; Wei, Xile

2014-09-01

Although the beneficial effects of chronic deep brain stimulation on Parkinson's disease motor symptoms are now largely confirmed, the underlying mechanisms behind deep brain stimulation remain unclear and under debate. Hence, the selection of stimulation parameters is full of challenges. Additionally, due to the complexity of neural system, together with omnipresent noises, the accurate model of thalamic relay neuron is unknown. Thus, the iterative learning control of the thalamic relay neuron's Parkinsonian state based on various variables is presented. Combining the iterative learning control with typical proportional-integral control algorithm, a novel and efficient control strategy is proposed, which does not require any particular knowledge on the detailed physiological characteristics of cortico-basal ganglia-thalamocortical loop and can automatically adjust the stimulation parameters. Simulation results demonstrate the feasibility of the proposed control strategy to restore the fidelity of thalamic relay in the Parkinsonian condition. Furthermore, through changing the important parameter—the maximum ionic conductance densities of low-threshold calcium current, the dominant characteristic of the proposed method which is independent of the accurate model can be further verified.

Reshaping supervisory practice in home care.

Science.gov (United States)

Knollmueller, R N

1988-06-01

Reshaping supervisory practice in home care is not an if but a when issue. We need the best wisdom in how to reshape the practice so that it builds on the experience of the individual and the agency. It is time to deliberately plan to change from the paper-shuffling tendency among supervisors toward supporting more people-oriented activity and to rediscover the pivotal role that supervisors have in keeping a community healthy, staff stimulated, and the agency solvent. Some summary points to consider in reshaping supervisory practice include: (1) redefine supervision to reflect what is desired, needed, and possible, (2) recognize the contribution from change theory and apply it, (3) recapture the commitment and philosophy of supervision from the past, (4) reward the supervisor commensurate with the scope of practice expected, (5) reverse selection of supervisors from preservers of territory to manager as idea entrepreneur, (6) respond to varying and dynamic models of supervisory practice, (7) recharge the supervisor through timely in-service programs, continuing education, and formal academic study, (8) require educational content and practice from colleges and universities that stimulate creative supervisory skills and improve job satisfaction, (9) respect the work of the supervisor and provide appropriate support to achieve success, (10) reconsider current supervisory models and expand opportunities for professional growth among staff, and (11) reshape the supervisory role from one of controller to facilitator and innovator.

Supervisory control of mobile sensor networks: math formulation, simulation, and implementation.

Science.gov (United States)

Giordano, Vincenzo; Ballal, Prasanna; Lewis, Frank; Turchiano, Biagio; Zhang, Jing Bing

2006-08-01

This paper uses a novel discrete-event controller (DEC) for the coordination of cooperating heterogeneous wireless sensor networks (WSNs) containing both unattended ground sensors (UGSs) and mobile sensor robots. The DEC sequences the most suitable tasks for each agent and assigns sensor resources according to the current perception of the environment. A matrix formulation makes this DEC particularly useful for WSN, where missions change and sensor agents may be added or may fail. WSN have peculiarities that complicate their supervisory control. Therefore, this paper introduces several new tools for DEC design and operation, including methods for generating the required supervisory matrices based on mission planning, methods for modifying the matrices in the event of failed nodes, or nodes entering the network, and a novel dynamic priority assignment weighting approach for selecting the most appropriate and useful sensors for a given mission task. The resulting DEC represents a complete dynamical description of the WSN system, which allows a fast programming of deployable WSN, a computer simulation analysis, and an efficient implementation. The DEC is actually implemented on an experimental wireless-sensor-network prototyping system. Both simulation and experimental results are presented to show the effectiveness and versatility of the developed control architecture.

MFTF supervisory control and diagnostics system hardware

International Nuclear Information System (INIS)

Butner, D.N.

1979-01-01

The Supervisory Control and Diagnostics System (SCDS) for the Mirror Fusion Test Facility (MFTF) is a multiprocessor minicomputer system designed so that for most single-point failures, the hardware may be quickly reconfigured to provide continued operation of the experiment. The system is made up of nine Perkin-Elmer computers - a mixture of 8/32's and 7/32's. Each computer has ports on a shared memory system consisting of two independent shared memory modules. Each processor can signal other processors through hardware external to the shared memory. The system communicates with the Local Control and Instrumentation System, which consists of approximately 65 microprocessors. Each of the six system processors has facilities for communicating with a group of microprocessors; the groups consist of from four to 24 microprocessors. There are hardware switches so that if an SCDS processor communicating with a group of microprocessors fails, another SCDS processor takes over the communication

Protective relay

International Nuclear Information System (INIS)

Lim, Mu Ji; Jung, Hae Sang

1974-10-01

This book is divided into two chapters, which deals with protective relay. The first chapter deals with the basic knowledge of relay on development of relay, classification of protective relay, rating of protective relay general structure of protective relay, detecting of ground protection, about point of contact, operating relay and trip relaying. The second chapter is about structure and explanation of relay on classification by structure such as motor type and moving-coil type, explanation of other relays over current relay, over voltage relay, short voltage relay, relay for power, relay for direction, test of over voltage relay, test of short voltage relay and test of directional circuit relay.

Critically Engaging "Mutually Engaged Supervisory Processes": A Proposed Theory for CPE Supervisory Education.

Science.gov (United States)

Fitchett, George; Altenbaumer, Mary L; Atta, Osofo Kwesi; Stowman, Sheryl Lyndes; Vlach, Kyle

2014-12-01

Revisions to the processes for training and certifying supervisors continue to be debated within the Association for Clinical Pastoral Education (ACPE). In 2012 Ragsdale and colleagues published, "Mutually engaged supervisory processes," a qualitative research study utilizing grounded theory based on interviews with 19 recently certified Associate CPE Supervisors, of nine components that facilitate the development of CPE supervisory education students. In this article we critically engage this theory and the research upon which it is based. We also reflect on three issues highlighted by the theory: personal transformation in CPE supervisory education, how CPE supervisory education students develop theoretical foundations for their work, and engaging multicultural issues in supervisory education. We conclude that this theory offers ACPE the possibility of using research to guide future modifications to its practice of Supervisory education. © 2014 Journal of Pastoral Care Publications Inc.

Supervisory Control Technique For An Assembly Workstation As A Dynamic Discrete Event System

Directory of Open Access Journals (Sweden)

Daniela Cristina CERNEGA

2001-12-01

Full Text Available This paper proposes a control problem statement in the framework of supervisory control technique for the assembly workstations. A desired behaviour of an assembly workstation is analysed. The behaviour of such a workstation is cyclic and some linguistic properties are established. In this paper, it is proposed an algorithm for the computation of the supremal controllable language of the closed system desired language. Copyright © 2001 IFAC.

A supervisory control approach in economic MPC design for refrigeration systems

DEFF Research Database (Denmark)

Shafiei, Seyed Ehsan; Stoustrup, Jakob; Rasmussen, Henrik

2013-01-01

A model predictive control at the supervisory level is proposed for refrigeration systems using price and temperature predictions. The control objective is to minimize the overall energy cost within the prediction horizon. The method is mainly developed for demand-side management in the future...... to rearrange the problem to facilitate convex programming. A nonlinear continuous time model validated by real data is employed to simulate system operation. The results show a considerable economic saving as well as a trade-off between the saving level and design complexity....

Supervisory control for a complex robotic system

International Nuclear Information System (INIS)

Miller, D.J.

1988-01-01

The Robotic Radiation Survey and Analysis System investigates the use of advanced robotic technology for performing remote radiation surveys on nuclear waste shipping casks. Robotic systems have the potential for reducing personnel exposure to radiation and providing fast reliable throughput at future repository sites. A primary technology issue is the integrated control of distributed specialized hardware through a modular supervisory software system. Automated programming of robot trajectories based upon mathematical models of the cask and robot coupled with sensory feedback enables flexible operation of a commercial gantry robot with the reliability needed to perform autonomous operations in a hazardous environment. Complexity is managed using structured software engineering techniques resulting in the generation of reusable command primitives which contribute to a software parts catalog for a generalized robot programming language

Safety Supervisory Strategy for an Upper-Limb Rehabilitation Robot Based on Impedance Control

Directory of Open Access Journals (Sweden)

Lizheng Pan

2013-02-01

Full Text Available User security is an important consideration for robots that interact with humans, especially for upper-limb rehabilitation robots, during the use of which stroke patients are often more susceptible to injury. In this paper, a novel safety supervisory control method incorporating fuzzy logic is proposed so as to guarantee the impaired limb's safety should an emergency situation occur and the robustness of the upper-limb rehabilitation robot control system. Firstly, a safety supervisory fuzzy controller (SSFC was designed based on the impaired-limb's real-time physical state by extracting and recognizing the impaired-limb's tracking movement features. Then, the proposed SSFC was used to automatically regulate the desired force either to account for reasonable disturbance resulting from pose or position changes or to respond in adequate time to an emergency based on an evaluation of the impaired-limb's physical condition. Finally, a position-based impedance controller was implemented to achieve compliance between the robotic end-effector and the impaired limb during the robot-assisted rehabilitation training. The experimental results show the effectiveness and potential of the proposed method for achieving safety and robustness for the rehabilitation robot.

Comparative response time and fault logging with a PLC and supervisory software and a standalone unit developed for recording

International Nuclear Information System (INIS)

Baldaconi, Ricardo H.; Costa, Fabio E. da

2017-01-01

The Cobalt-60 irradiator of IPEN / CNEN, a category IV facility, has a security system for inter locking doors or exposure of radioactive sources made simultaneously by a programmable logic controller (PLC) model S7-200 from Siemens and a relay logic. From a set of information, both systems work together opening doors or exposing the sources. All incoming and outgoing information are sent serially via EIA232 communication to a personal computer with Windows® platform for a supervisory program which provides the monitoring of the entire process by a synoptic table on the computer screen and is also intended to keep records of all events on the computer's hard drive. A deficiency was found for the process of sending events via serial communication (EIA232) from PLC to the supervisory program. When failure occurred in a very short time, the PLC always took the right decision, but the registration process that had to go through the Windows® timeshare lost the information. In the previous work developed a standalone electronics unit connected to the inputs and outputs of the security system, fully optocoupled to avoid any interference to the security system that records each event on a memory card. In this work, for checking the unit developed record time ability, transients incoming signals for simulating failures, were injected at security system inputs and the response time of security system, supervisory program and the autonomous unity were measured and compared. (author)

Comparative response time and fault logging with a PLC and supervisory software and a standalone unit developed for recording

Energy Technology Data Exchange (ETDEWEB)

Baldaconi, Ricardo H., E-mail: ricardohovacker@hotmail.com [Escola Senai Roberto Simonsen, Educação e Tecnologia, Sao Paulo, SP (Brazil); Costa, Fabio E. da, E-mail: fecosta@ipen.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

2017-07-01

The Cobalt-60 irradiator of IPEN / CNEN, a category IV facility, has a security system for inter locking doors or exposure of radioactive sources made simultaneously by a programmable logic controller (PLC) model S7-200 from Siemens and a relay logic. From a set of information, both systems work together opening doors or exposing the sources. All incoming and outgoing information are sent serially via EIA232 communication to a personal computer with Windows® platform for a supervisory program which provides the monitoring of the entire process by a synoptic table on the computer screen and is also intended to keep records of all events on the computer's hard drive. A deficiency was found for the process of sending events via serial communication (EIA232) from PLC to the supervisory program. When failure occurred in a very short time, the PLC always took the right decision, but the registration process that had to go through the Windows® timeshare lost the information. In the previous work developed a standalone electronics unit connected to the inputs and outputs of the security system, fully optocoupled to avoid any interference to the security system that records each event on a memory card. In this work, for checking the unit developed record time ability, transients incoming signals for simulating failures, were injected at security system inputs and the response time of security system, supervisory program and the autonomous unity were measured and compared. (author)

The Use of Intelligent Relays for the Sewer Cleaning Vehicle Control and Automation

Directory of Open Access Journals (Sweden)

O. Chiver

2012-06-01

Full Text Available The paper presents the way in which the electrical control and automation system of the 5 mc combined sewer and gully cleaning vehicle equipped by a local company was designed, using the intelligent relay of the easy 700 type of Moeller (Eaton company. The control of all the equipments is performed locally from the control panel and some of them can also by remote controlled by means of the radio waves. The program required by the intelligent relay was created, tested and implemented with the help of the dedicated software easy-soft 6, developed by the manufacturing company.

Analysis of errors of radiation relay, (1)

International Nuclear Information System (INIS)

Koyanagi, Takami; Nakajima, Sinichi

1976-01-01

The statistical error of liquid level controlled by radiation relay is analysed and a method of minimizing the error is proposed. This method comes to the problem of optimum setting of the time constant of radiation relay. The equations for obtaining the value of time constant are presented and the numerical results are shown in a table and plotted in a figure. The optimum time constant of the upper level control relay is entirely different from that of the lower level control relay. (auth.)

Operations and maintenance manual for the LDUA supervisory control and data acquisition system (LDUA System 4200) and control network (LDUA System 4400)

International Nuclear Information System (INIS)

Barnes, G.A.

1998-01-01

This document defines the requirements applicable to the operation, maintenance and storage of the Supervisory Control and Data Acquisition System (SCADAS) and Control Network in support of the Light Duty Utility Arm (LDUA) operations

Overview of MFTF supervisory control and diagnostics system software

International Nuclear Information System (INIS)

Ng, W.C.

1979-01-01

The Mirror Fusion Test Facility (MFTF) at the Lawrence Livermore Laboratory (LLL) is currently the largest mirror fusion research project in the world. Its Control and Diagnostics System is handled by a distributed computer network consisting of nine Interdata minicomputer systems and about 65 microprocessors. One of the design requirements is tolerance of single-point failure. If one of the computer systems becomes inoperative, the experiment can still be carried out, although the system responsiveness to operator command may be degraded. In a normal experiment cycle, the researcher can examine the result of the previous experiment, change any control parameter, fire a shot, collect four million bytes of diagnostics data, perform intershot analysis, and have the result presented - all within five minutes. The software approach adopted for the Supervisory Control and Diagnostics System features chief programmer teams and structured programming. Pascal is the standard programming language in this project

Decision Support in Supervisory Control of High-Risk Industrial Systems

DEFF Research Database (Denmark)

Rasmussen, Jens; Goodstein, L. P.

1987-01-01

available to the operators their conceptual models and their processing resources so as to allow the operators to function as their extended arm in coping with the plant. Such as interactive decision-making activity would thus benefit from this simultaneous availability of the design basis, up......It is argued that the supervisory control of complex industrial processes having a potential for serious consequences in case of accidents requires careful consideration of the allocation of decision making between the three main agents of control; namely the designer, the operator...... and the automatic control system. In particular, it is advocated that, instead of continuing their efforts to make their preplanning of responses and countermeasures more and more complete and thus restrict the operators' own initiative, designers should take advantage of modern information technology to make...

RoCoMAR: Robots' Controllable Mobility Aided Routing and Relay Architecture for Mobile Sensor Networks

Science.gov (United States)

Van Le, Duc; Oh, Hoon; Yoon, Seokhoon

2013-01-01

In a practical deployment, mobile sensor network (MSN) suffers from a low performance due to high node mobility, time-varying wireless channel properties, and obstacles between communicating nodes. In order to tackle the problem of low network performance and provide a desired end-to-end data transfer quality, in this paper we propose a novel ad hoc routing and relaying architecture, namely RoCoMAR (Robots' Controllable Mobility Aided Routing) that uses robotic nodes' controllable mobility. RoCoMAR repeatedly performs link reinforcement process with the objective of maximizing the network throughput, in which the link with the lowest quality on the path is identified and replaced with high quality links by placing a robotic node as a relay at an optimal position. The robotic node resigns as a relay if the objective is achieved or no more gain can be obtained with a new relay. Once placed as a relay, the robotic node performs adaptive link maintenance by adjusting its position according to the movements of regular nodes. The simulation results show that RoCoMAR outperforms existing ad hoc routing protocols for MSN in terms of network throughput and end-to-end delay. PMID:23881134

RoCoMAR: Robots’ Controllable Mobility Aided Routing and Relay Architecture for Mobile Sensor Networks

Directory of Open Access Journals (Sweden)

Seokhoon Yoon

2013-07-01

Full Text Available In a practical deployment, mobile sensor network (MSN suffers from a low performance due to high node mobility, time-varying wireless channel properties, and obstacles between communicating nodes. In order to tackle the problem of low network performance and provide a desired end-to-end data transfer quality, in this paper we propose a novel ad hoc routing and relaying architecture, namely RoCoMAR (Robots’ Controllable Mobility Aided Routing that uses robotic nodes’ controllable mobility. RoCoMAR repeatedly performs link reinforcement process with the objective of maximizing the network throughput, in which the link with the lowest quality on the path is identified and replaced with high quality links by placing a robotic node as a relay at an optimal position. The robotic node resigns as a relay if the objective is achieved or no more gain can be obtained with a new relay. Once placed as a relay, the robotic node performs adaptive link maintenance by adjusting its position according to the movements of regular nodes. The simulation results show that RoCoMAR outperforms existing ad hoc routing protocols for MSN in terms of network throughput and end-to-end delay.

Laboratory technical services provides business opportunities for supervisory control and data acquisition systems

International Nuclear Information System (INIS)

Ballard, W.

1994-01-01

The author presents some additional information about what he considers are some really great opportunities for the business community to participate in developing the greatest scientific project in the history of mankind. Facility Engineering Services is part of Laboratory Technical Services. As part of this group, it has the responsibility to direct the construction of interim facilities, scientific labs, production process, cooling towers, cooling ponds and the operation and control of SSC Laboratory conventional support systems. These operations and controls will be accomplished through the employment of a Supervisory Control and Data Acquisition system (SCADA)

The Supervisory Control System for the HL-2A Neutral Beam Injector

Science.gov (United States)

Li, Bo; Li, Li; Feng, Kun; Wang, Xueyun; Yang, Jiaxing; Huang, Zhihui; Kang, Zihua; Wang, Mingwei; Zhang, Guoqing; Lei, Guangjiu; Rao, Jun

2009-06-01

Supervisory control and protection system of the neutral beam injector (NBI) in the HL-2A tokamak is presented. The system is used for a safe coordination of all the main NBI subsystems. Because the system is based on computer networks with its transmission medium of optical fiber, its advantages in high operational stability, reliability, security and flexible functional expandability are clearly shown during the NBI commissioning and heating experiment in HL-2A.

Regime-based supervisory control to reduce power fluctuations from offshore wind power plants

DEFF Research Database (Denmark)

Barahona Garzón, Braulio; Cutululis, Nicolaos Antonio; Trombe, Pierre-Julien

2013-01-01

Wind power fluctuations, especially offshore, can pose challenges in the secure and stable operation of the power system. In modern large offshore wind farms, there are supervisory controls designed to reduce the power fluctuations. Their operation is limited due to the fact that they imply loss...... that consider different wind power regimes to derive control setpoints by using a Markov-Switching AutoRegressive model. We evaluate the performance versus measured data in terms of power ramp characteristics and energy efficiency....

Opportunistic relaying in multipath and slow fading channel: Relay selection and optimal relay selection period

KAUST Repository

Sungjoon Park,

2011-11-01

In this paper we present opportunistic relay communication strategies of decode and forward relaying. The channel that we are considering includes pathloss, shadowing, and fast fading effects. We find a simple outage probability formula for opportunistic relaying in the channel, and validate the results by comparing it with the exact outage probability. Also, we suggest a new relay selection algorithm that incorporates shadowing. We consider a protocol of broadcasting the channel gain of the previously selected relay. This saves resources in slow fading channel by reducing collisions in relay selection. We further investigate the optimal relay selection period to maximize the throughput while avoiding selection overhead. © 2011 IEEE.

An analysis of the operation of a single-pole relay integrated circuit device with a controlled reset ratio

Energy Technology Data Exchange (ETDEWEB)

Reshetov, N.E.

1980-01-01

Relay equipment using semiconductor components (such as those containing gates using planar transformers, and a relay in networks which control the operational time of a relay) are widely used in the automation equipment of electric power systems. A scheme where a gate in the form of an integrated circuit is used is given.

Admission Control Threshold in Cellular Relay Networks with Power Adjustment

Directory of Open Access Journals (Sweden)

Lee Ki-Dong

2009-01-01

Full Text Available Abstract In the cellular network with relays, the mobile station can benefit from both coverage extension and capacity enhancement. However, the operation complexity increases as the number of relays grows up. Furthermore, in the cellular network with cooperative relays, it is even more complex because of an increased dimension of signal-to-noise ratios (SNRs formed in the cooperative wireless transmission links. In this paper, we propose a new method for admission capacity planning in a cellular network using a cooperative relaying mechanism called decode-and-forward. We mathematically formulate the dropping ratio using the randomness of "channel gain." With this, we formulate an admission threshold planning problem as a simple optimization problem, where we maximize the accommodation capacity (in number of connections subject to two types of constraints. (1 A constraint that the sum of the transmit powers of the source node and relay node is upper-bounded where both nodes can jointly adjust the transmit power. (2 A constraint that the dropping ratio is upper-bounded by a certain threshold value. The simplicity of the problem formulation facilitates its solution in real-time. We believe that the proposed planning method can provide an attractive guideline for dimensioning a cellular relay network with cooperative relays.

The structure and operation scheme of an automatic and supervisory control system for KEPCO UPFC

Energy Technology Data Exchange (ETDEWEB)

Ahn, S.J.; Lee, D.W.; Moon, S.I. [Seoul National Univ., Seoul (Korea, Republic of). School of Electrical Engineering

2007-07-01

The structure and functions of a control system that can be used for automatic and supervisory control of a unified power flow controller (UPFC) was presented. A UPFC is a device used in power electronic based transmission to allow the independent control of active and reactive power flows as well as the simultaneous control of voltage profile. The Korea Electric Power Corporation (KEPCO) installed a {+-}80 MVA UPFC at the 154 kV Kangjin substation, operated in the Kangjin-Jangheung transmission line. The operation strategies used in both the normal state and emergency state were presented along with a scheme that includes the minimization of active power loss, coordination of voltage/Var control with an under load tap changer (ULTC), and better system security. Although this UPFC is operated by set-point control, it has some limitations, particularly in emergency events. In order to overcome the limitation of set-point control, this paper proposed the automatic and supervisory control system connected to a local SCADA for data exchange. The primary function of the system is to analyze the state of the power system, determine the control objectives and to calculate the optimal power flow. Details of each of these functions was described in this paper along with a detailed algorithm for each scheme. 5 refs., 6 figs.

Supervisory Control and Data Acquisition (SCADA) Systems and Cyber-Security: Best Practices to Secure Critical Infrastructure

Science.gov (United States)

Morsey, Christopher

2017-01-01

In the critical infrastructure world, many critical infrastructure sectors use a Supervisory Control and Data Acquisition (SCADA) system. The sectors that use SCADA systems are the electric power, nuclear power and water. These systems are used to control, monitor and extract data from the systems that give us all the ability to light our homes…

Advanced Strategic and Tactical Relay Request Management for the Mars Relay Operations Service

Science.gov (United States)

Allard, Daniel A.; Wallick, Michael N.; Gladden, Roy E.; Wang, Paul; Hy, Franklin H.

2013-01-01

This software provides a new set of capabilities for the Mars Relay Operations Service (MaROS) in support of Strategic and Tactical relay, including a highly interactive relay request Web user interface, mission control over relay planning time periods, and mission management of allowed strategic vs. tactical request parameters. Together, these new capabilities expand the scope of the system to include all elements critical for Tactical relay operations. Planning of replay activities spans a time period that is split into two distinct phases. The first phase is called Strategic, which begins at the time that relay opportunities are identified, and concludes at the point that the orbiter generates the flight sequences for on board execution. Any relay request changes from this point on are called Tactical. Tactical requests, otherwise called Orbit - er Relay State Changes (ORSC), are highly restricted in terms of what types of changes can be made, and the types of parameters that can be changed may differ from one orbiter to the next. For example, one orbiter may be able to delay the start of a relay request, while another may not. The legacy approach to ORSC management involves exchanges of e-mail with "requests for change" and "acknowledgement of approval," with no other tracking of changes outside of e-mail folders. MaROS Phases 1 and 2 provided the infrastructure for strategic relay for all supported missions. This new version, 3.0, introduces several capabilities that fully expand the scope of the system to include tactical relay. One new feature allows orbiter users to manage and "lock" Planning Periods, which allows the orbiter team to formalize the changeover from Strategic to Tactical operations. Another major feature allows users to interactively submit tactical request changes via a Web user interface. A third new feature allows orbiter missions to specify allowed tactical updates, which are automatically incorporated into the tactical change process

Automatic Generation of Supervisory Control System Software Using Graph Composition

Science.gov (United States)

Nakata, Hideo; Sano, Tatsuro; Kojima, Taizo; Seo, Kazuo; Uchida, Tomoyuki; Nakamura, Yasuaki

This paper describes the automatic generation of system descriptions for SCADA (Supervisory Control And Data Acquisition) systems. The proposed method produces various types of data and programs for SCADA systems from equipment definitions using conversion rules. At first, this method makes directed graphs, which represent connections between the equipment, from equipment definitions. System descriptions are generated using the conversion rules, by analyzing these directed graphs, and finding the groups of equipment that involve similar operations. This method can make the conversion rules multi levels by using the composition of graphs, and can reduce the number of rules. The developer can define and manage these rules efficiently.

Iterative Relay Scheduling with Hybrid ARQ under Multiple User Equipment (Type II) Relay Environments

KAUST Repository

Nam, Sung Sik

2018-01-09

In this work, we propose an iterative relay scheduling with hybrid ARQ (IRS-HARQ) scheme which realizes fast jump-in/successive relaying and subframe-based decoding under the multiple user equipment (UE) relay environments applicable to the next-generation cellular systems (e.g., LTE-Advanced and beyond). The proposed IRS-HARQ aims to increase the achievable data rate by iteratively scheduling a relatively better UE relay closer to the end user in a probabilistic sense, provided that the relay-to-end user link should be operated in an open-loop and transparent mode. The latter is due to the fact that not only there are no dedicated control channels between the UE relay and the end user but also a new cell is not created. Under this open-loop and transparent mode, our proposed protocol is implemented by partially exploiting the channel state information based on the overhearing mechanism of ACK/NACK for HARQ. Further, the iterative scheduling enables UE-to-UE direct communication with proximity that offers spatial frequency reuse and energy saving.

RTE - Report by the Chairman of the Supervisory Board 2016

International Nuclear Information System (INIS)

2017-01-01

The Chairman of the Supervisory Board of RTE (Reseau de Transport d'Electricite) draws up and publishes an annual report on corporate governance and internal control procedures, in application of Paragraph 7 of Article L. 225-68 of French company law (Code de Commerce). This is a requirement on companies whose shares are traded on a regulated market, as is the case of RTE. Paragraph 7 of Article L. 225-68 of French company law (Code de Commerce) stipulates that the report must present: the composition of the Supervisory Board and the application of the principle of equal representation of men and women, the conditions of preparing and organising the work of the Supervisory Board, internal control and risk management procedures implemented by the company, the corporate governance code to which the company adheres. Additionally, this report must set out: the principles for determining the remuneration of senior executives, specific provisions relating to the involvement of shareholders at the General Meeting of Shareholders. Within RTE, this report has been prepared by the Legal Affairs Department, which directed a work team. They reported on the functioning of the Supervisory Board and the implementation of internal control and risk management procedures, both for RTE and for its subsidiaries. The present report was approved by the Executive Board and was submitted to the Statutory Auditors. It was then presented to the Economic and Audit Supervisory Committee on 07 February 2017 and the Supervisory Board on 09 February 2017. The report was published at the same time as the activity report, the management report and consolidated accounts, annual accounts and the sustainability report. This document takes account of the various recommendations published by the French Financial Markets Authority (AMF)

Development of a supervisory control and data acquisitioning system

International Nuclear Information System (INIS)

Kamboh, A.M.; Fakhar, H.A.; Rafiq, G.; Kazmi, S.R.

2004-01-01

This paper describes a Supervisory Control and Data Acquisitioning system called SCADA that we have developed at NUST. This research is aimed at the development of a network where a central Control Server extends bidirectional data exchange capability to hundreds of geographically remote sensors and actuators spread over a distance greater than 3 Km. Several battery-driven handheld terminals called Remote Terminal Units (RTU) have been designed to provide both wired and wireless connectivity between sensors and the network, also adding limited mobility to the sensors. Simple transceivers give the RTUs wireless access to network. The Human-Machine Intel (HMI) for the RTUs and the Server have been provided. A repeater has also been designed to increase the number of RTUs connected, and the maximum allowed distance between units and the server. The wired network gives several times faster connectivity than the wireless network, in addition to the larger area covered, but at the cost of mobility. (author)

Application of functional analysis techniques to supervisory systems

International Nuclear Information System (INIS)

Lambert, Manuel; Riera, Bernard; Martel, Gregory

1999-01-01

The aim of this paper is to apply firstly two interesting functional analysis techniques for the design of supervisory systems for complex processes, and secondly to discuss the strength and the weaknesses of each of them. Two functional analysis techniques have been applied, SADT (Structured Analysis and Design Technique) and FAST (Functional Analysis System Technique) on a process, an example of a Water Supply Process Control (WSPC) system. These techniques allow a functional description of industrial processes. The paper briefly discusses the functions of a supervisory system and some advantages of the application of functional analysis for the design of a 'human' centered supervisory system. Then the basic principles of the two techniques applied on the WSPC system are presented. Finally, the different results obtained from the two techniques are discussed

49 CFR 236.52 - Relayed cut-section.

Science.gov (United States)

2010-10-01

..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and Instructions: All Systems Track Circuits § 236.52 Relayed cut-section. Where relayed cut-section is used in... 49 Transportation 4 2010-10-01 2010-10-01 false Relayed cut-section. 236.52 Section 236.52...

Modified Dynamic Decode-and-Forward Relaying Protocol for Type II Relay in LTE-Advanced and Beyond.

Science.gov (United States)

Nam, Sung Sik; Alouini, Mohamed-Slim; Choi, Seyeong

2016-01-01

In this paper, we propose a modified dynamic decode-and-forward (MoDDF) relaying protocol to meet the critical requirements for user equipment (UE) relays in next-generation cellular systems (e.g., LTE-Advanced and beyond). The proposed MoDDF realizes the fast jump-in relaying and the sequential decoding with an application of random codeset to encoding and re-encoding process at the source and the multiple UE relays, respectively. A subframe-by-subframe decoding based on the accumulated (or buffered) messages is employed to achieve energy, information, or mixed combining. Finally, possible early termination of decoding at the end user can lead to the higher spectral efficiency and more energy saving by reducing the frequency of redundant subframe transmission and decoding. These attractive features eliminate the need of directly exchanging control messages between multiple UE relays and the end user, which is an important prerequisite for the practical UE relay deployment.

Protective and control relays as coal-mine power-supply ACS subsystem

Science.gov (United States)

Kostin, V. N.; Minakova, T. E.

2017-10-01

The paper presents instantaneous selective short-circuit protection for the cabling of the underground part of a coal mine and central control algorithms as a Coal-Mine Power-Supply ACS Subsystem. In order to improve the reliability of electricity supply and reduce the mining equipment down-time, a dual channel relay protection and central control system is proposed as a subsystem of the coal-mine power-supply automated control system (PS ACS).

Microcomputer relay regulator in the CAMAC standard

International Nuclear Information System (INIS)

Nikolaev, V.P.

1984-01-01

The digital relay regulator is developed on the base of the KM001 microcomputer and KK06 controller for automatic control ob ects with transfer functions describing a broad class of systems using actuating motors (stabilitation, follow-up systems). The CAMAC relay-unit realizes the regulation law and provides the possibility to control analogous values by 8 channels

Programmable controllers replace relays in MFTF-B personnel-safety interlocks

International Nuclear Information System (INIS)

Branum, J.D.

1981-01-01

This paper describes a new approach for implementing personnel safety interlocks logic using industrial-type programmable controllers. The logic for all personnel safety interlocks except those totally internal to a subsystem is implemented in two non-redundant controllers. A high degree of fail-safe reliability is achieved by augmenting the protective features intrinsic to each controller with those provided by a small amount of external support hardware. The controllers are interfaced to the host computer system via fiber optic data links to enable display of interlock and overall system status on the control room graphic displays. When fully implemented, the controllers will perform the equivalent of over 2000 discreet relay functions

Rate Control for Network-Coded Multipath Relaying with Time-Varying Connectivity

Science.gov (United States)

2010-12-10

Armen Babikyan, Nathaniel M. Jones, Thomas H. Shake, and Andrew P. Worthen MIT Lincoln Laboratory 244 Wood Street Lexington, MA 02420 DDRE, 1777...delay U U U U SAR 11 Zach Sweet 781-981-5997 1 Rate Control for Network-Coded Multipath Relaying with Time-Varying Connectivity Brooke Shrader, Armen

Pupillary Response as an Indicator of Processing Demands Within a Supervisory Control Simulation Environment

Science.gov (United States)

2015-05-07

Yerkes, R.M., and Dodson, J.D. (1908). The relation of strength of stimulus to rapidity of habit -formation. Journal of comparative neurology and psychology 18, 459-482. ...the amount of mental effort exerted (Kahneman, 1973; Beatty & Lucero-Wagoner, 2000; Andreassi, 2007). The vast majority of these studies , however...of this initial study , the authors were interested in investigating whether pupillometry data collected in a realistic UAV supervisory control

Alternate transmission with half-duplex relaying in MIMO interference relay networks

KAUST Repository

Park, Seongho

2013-12-01

In this paper, we consider an alternate transmission scheme for a multiple-input multiple-output interference relay channel where multiple sources transmit their own signals to their corresponding destinations via one of two relaying groups alternately every time phase. Each of the relaying groups has arbitrary number of relays, and each relay operates in half-duplex amplify-and-forward mode. In our scheme, the received signals at the relay nodes consist of desired signals and two different interference signals such as the inter-source interferences and the inter-group interferences which are caused by the phase incoherence of relaying. As such, we propose an iterative interference alignment algorithm to mitigate the interferences. We show that our proposed scheme achieves additional degrees of freedom compared to the conventional half-duplex relaying system in the interference relay channels. © 2013 IEEE.

Dynamic Relaying in 3GPP LTE-Advanced Networks

DEFF Research Database (Denmark)

Teyeb, Oumer Mohammed; Van Phan, Vinh; Redana, Simone

2009-01-01

Relaying is one of the proposed technologies for LTE-Advanced networks. In order to enable a flexible and reliable relaying support, the currently adopted architectural structure of LTE networks has to be modified. In this paper, we extend the LTE architecture to enable dynamic relaying, while...... maintaining backward compatibility with LTE Release 8 user equipments, and without limiting the flexibility and reliability expected from relaying.With dynamic relaying, relays can be associated with base stations on a need basis rather than in a fixed manner which is based only on initial radio planning....... Proposals are also given on how to further improve a relay enhanced LTE network by enabling multiple interfaces between the relay nodes and their controlling base stations, which can possibly be based on technologies different from LTE, so that load balancing can be realized. This load balancing can...

Alternate MIMO relaying with three AF relays using interference alignment

KAUST Repository

Park, Kihong

2012-06-01

In this paper, we study a two-hop half-duplex relaying network with one source, one destination, and three amplify-and-forward (AF) relays equipped with M antennas each. We consider alternate transmission to compensate for the inherent loss of capacity pre-log factor 1/2 in half duplex mode, where source transmit message to two relays and the other relay alternately. The inter-relay interference caused by alternate transmission is aligned to make additional degrees of freedom (DOFs). It is shown that the proposed scheme enables us to exploit 3M/4 DOFs compared with the M/2 DOFs of conventional AF relaying. More specifically, suboptimal linear filter designs for a source and three relays are proposed to maximize the achievable sum-rate. We verify using some selected numerical results that the proposed filter designs give significant improvement of the sum-rate over a naive filter and conventional relaying schemes. © 2012 IEEE.

Distance relay performance in future converter dominated power systems

DEFF Research Database (Denmark)

Sarkar, Moumita; Jia, Jundi; Yang, Guangya

2017-01-01

Increasing penetration of converter-based generations in power system has led to new system challenges. Short circuit power response from converter-based generations is different from that of traditional synchronous generators. Power electronic converters can be designed for over-current only up ...... of converter controls on fault current response of converter-based generations is also investigated. Index Terms—Converter control, distance relays, power system protection, system modelling....... to 1.1-1.25 times of its nominal value. Low availability of short circuit power can cause many challenges such as misoperation of distance relays. The aim of this paper is to investigate the effect of converter dominated systems on performance of distance relays. Backup functionality of the distance...... relay is major concern as miscoordination of backup relays in case of cascading faults can lead to severe stress in system, which can develop into blackout. In this paper, response of relays in traditional system is compared with response of relays in low short-circuit-current power systems. Impact...

Relay race

CERN Multimedia

Staff Association

2011-01-01

The CERN relay race will take place around the Meyrin site on Thursday 19th May starting at 12:15. If possible, please avoid driving on the site during this 20-minute period. If you do meet runners while driving your car, please STOP until they have all passed. Thank you for your cooperation. Details on the course, and how to register your team for the relay race, can be found at: https://espace.cern.ch/Running-Club/CERN-Relay Some advice for all runners from the medical service can also be found here: https://espace.cern.ch/Running-Club/CERN-Relay/RelayPagePictures/MedicalServiceAnnoncement.pdf

Relay race

CERN Document Server

Staff Association

2011-01-01

The CERN relay race will take place around the Meyrin site on Thursday 19th May starting at 12·15. If possible, please avoid driving on the site during this 20-minute period. If you do meet runners while driving your car, please STOP until they have all passed. Thank you for your cooperation. Details on the course, and how to register your team for the relay race, can be found at: https://espace.cern.ch/Running-Club/CERN-Relay Some advice for all runners from the medical service can also be found here: https://espace.cern.ch/Running-Club/CERN-Relay/RelayPagePictures/MedicalServiceAnnoncement.pdf

Reversal thyristor-relay direct current commutator

International Nuclear Information System (INIS)

Ivanenko, A.I.

1982-01-01

A thyristor-relay commutator used for alteration of the leading magnetic field direction in experiments with polarized neutrons is described. The commutator flowsheet is presented. Thyristors, connected so as to allow the relay trigger operation mode, are used as controllable electronic relay. Two connected in series coils with the total inductance of the order of 0.28 H serve as the electronic relay load. The arc-free current commutation is effected at the moment of the minimal current across the load terminals, which allows to easily reverse the current up to 10 A at a volatage, v <= 150 V. The experience gained within a year of operation has shown that the commutator meets the requirements of reliability and tuning

Supervisory Styles: A Contingency Framework

Science.gov (United States)

Boehe, Dirk Michael

2016-01-01

While the contingent nature of doctoral supervision has been acknowledged, the literature on supervisory styles has yet to deliver a theory-based contingency framework. A contingency framework can assist supervisors and research students in identifying appropriate supervisory styles under varying circumstances. The conceptual study reported here…

Experimental evaluation of earthquake induced relay chattering

International Nuclear Information System (INIS)

Bandyopadhyay, K.; Hofmayer, C.; Shteyngart, S.

1990-01-01

An experimental evaluation of relay performance under vibratory environments is discussed in this paper. Single frequency excitation was used for most tests. Limited tests were performed with random multifrequency inputs. The capacity of each relay was established based on a two-millisecond chatter criterion. The experimental techniques are described and the effects of parameters in controlling the relay capacity levels are illustrated with test data. A wide variation of the capacity levels was observed due to the influence of parameters related to the design of the relay and nature of the input motion. 3 refs., 15 figs

Some optimal considerations in attitude control systems. [evaluation of value of relative weighting between time and fuel for relay control law

Science.gov (United States)

Boland, J. S., III

1973-01-01

The conventional six-engine reaction control jet relay attitude control law with deadband is shown to be a good linear approximation to a weighted time-fuel optimal control law. Techniques for evaluating the value of the relative weighting between time and fuel for a particular relay control law is studied along with techniques to interrelate other parameters for the two control laws. Vehicle attitude control laws employing control moment gyros are then investigated. Steering laws obtained from the expression for the reaction torque of the gyro configuration are compared to a total optimal attitude control law that is derived from optimal linear regulator theory. This total optimal attitude control law has computational disadvantages in the solving of the matrix Riccati equation. Several computational algorithms for solving the matrix Riccati equation are investigated with respect to accuracy, computational storage requirements, and computational speed.

Dynamic Relaying in 3GPP LTE-Advanced Networks

Directory of Open Access Journals (Sweden)

Van Phan Vinh

2009-01-01

Full Text Available Relaying is one of the proposed technologies for LTE-Advanced networks. In order to enable a flexible and reliable relaying support, the currently adopted architectural structure of LTE networks has to be modified. In this paper, we extend the LTE architecture to enable dynamic relaying, while maintaining backward compatibility with LTE Release 8 user equipments, and without limiting the flexibility and reliability expected from relaying. With dynamic relaying, relays can be associated with base stations on a need basis rather than in a fixed manner which is based only on initial radio planning. Proposals are also given on how to further improve a relay enhanced LTE network by enabling multiple interfaces between the relay nodes and their controlling base stations, which can possibly be based on technologies different from LTE, so that load balancing can be realized. This load balancing can be either between different base stations or even between different networks.

Modified Dynamic Decode-and-Forward Relaying Protocol for Type II Relay in LTE-Advanced and Beyond

KAUST Repository

Nam, Sung Sik; Alouini, Mohamed-Slim; Choi, Seyeong

2016-01-01

In this paper, we propose a modified dynamic decode-and-forward (MoDDF) relaying protocol to meet the critical requirements for user equipment (UE) relays in next-generation cellular systems (e.g., LTE-Advanced and beyond). The proposed MoDDF realizes the fast jump-in relaying and the sequential decoding with an application of random codeset to encoding and re-encoding process at the source and the multiple UE relays, respectively. A subframe-by-subframe decoding based on the accumulated (or buffered) messages is employed to achieve energy, information, or mixed combining. Finally, possible early termination of decoding at the end user can lead to the higher spectral efficiency and more energy saving by reducing the frequency of redundant subframe transmission and decoding. These attractive features eliminate the need of directly exchanging control messages between multiple UE relays and the end user, which is an important prerequisite for the practical UE relay deployment. Copyright: © 2016 Nam et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Modified Dynamic Decode-and-Forward Relaying Protocol for Type II Relay in LTE-Advanced and Beyond

KAUST Repository

Nam, Sung Sik

2016-11-29

In this paper, we propose a modified dynamic decode-and-forward (MoDDF) relaying protocol to meet the critical requirements for user equipment (UE) relays in next-generation cellular systems (e.g., LTE-Advanced and beyond). The proposed MoDDF realizes the fast jump-in relaying and the sequential decoding with an application of random codeset to encoding and re-encoding process at the source and the multiple UE relays, respectively. A subframe-by-subframe decoding based on the accumulated (or buffered) messages is employed to achieve energy, information, or mixed combining. Finally, possible early termination of decoding at the end user can lead to the higher spectral efficiency and more energy saving by reducing the frequency of redundant subframe transmission and decoding. These attractive features eliminate the need of directly exchanging control messages between multiple UE relays and the end user, which is an important prerequisite for the practical UE relay deployment. Copyright: © 2016 Nam et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Team performance in networked supervisory control of unmanned air vehicles: effects of automation, working memory, and communication content.

Science.gov (United States)

McKendrick, Ryan; Shaw, Tyler; de Visser, Ewart; Saqer, Haneen; Kidwell, Brian; Parasuraman, Raja

2014-05-01

Assess team performance within a net-worked supervisory control setting while manipulating automated decision aids and monitoring team communication and working memory ability. Networked systems such as multi-unmanned air vehicle (UAV) supervision have complex properties that make prediction of human-system performance difficult. Automated decision aid can provide valuable information to operators, individual abilities can limit or facilitate team performance, and team communication patterns can alter how effectively individuals work together. We hypothesized that reliable automation, higher working memory capacity, and increased communication rates of task-relevant information would offset performance decrements attributed to high task load. Two-person teams performed a simulated air defense task with two levels of task load and three levels of automated aid reliability. Teams communicated and received decision aid messages via chat window text messages. Task Load x Automation effects were significant across all performance measures. Reliable automation limited the decline in team performance with increasing task load. Average team spatial working memory was a stronger predictor than other measures of team working memory. Frequency of team rapport and enemy location communications positively related to team performance, and word count was negatively related to team performance. Reliable decision aiding mitigated team performance decline during increased task load during multi-UAV supervisory control. Team spatial working memory, communication of spatial information, and team rapport predicted team success. An automated decision aid can improve team performance under high task load. Assessment of spatial working memory and the communication of task-relevant information can help in operator and team selection in supervisory control systems.

Definition of a Robust Supervisory Control Scheme for Sodium-Cooled Fast Reactors

Energy Technology Data Exchange (ETDEWEB)

Ponciroli, R.; Passerini, S.; Vilim, R. B.

2016-04-17

In this work, an innovative control approach for metal-fueled Sodium-cooled Fast Reactors is proposed. With respect to the classical approach adopted for base-load Nuclear Power Plants, an alternative control strategy for operating the reactor at different power levels by respecting the system physical constraints is presented. In order to achieve a higher operational flexibility along with ensuring that the implemented control loops do not influence the system inherent passive safety features, a dedicated supervisory control scheme for the dynamic definition of the corresponding set-points to be supplied to the PID controllers is designed. In particular, the traditional approach based on the adoption of tabulated lookup tables for the set-point definition is found not to be robust enough when failures of the implemented SISO (Single Input Single Output) actuators occur. Therefore, a feedback algorithm based on the Reference Governor approach, which allows for the optimization of reference signals according to the system operating conditions, is proposed.

CDP - Adaptive Supervisory Control and Data Acquisition (SCADA) Technology for Infrastructure Protection

Energy Technology Data Exchange (ETDEWEB)

Marco Carvalho; Richard Ford

2012-05-14

Supervisory Control and Data Acquisition (SCADA) Systems are a type of Industrial Control System characterized by the centralized (or hierarchical) monitoring and control of geographically dispersed assets. SCADA systems combine acquisition and network components to provide data gathering, transmission, and visualization for centralized monitoring and control. However these integrated capabilities, especially when built over legacy systems and protocols, generally result in vulnerabilities that can be exploited by attackers, with potentially disastrous consequences. Our research project proposal was to investigate new approaches for secure and survivable SCADA systems. In particular, we were interested in the resilience and adaptability of large-scale mission-critical monitoring and control infrastructures. Our research proposal was divided in two main tasks. The first task was centered on the design and investigation of algorithms for survivable SCADA systems and a prototype framework demonstration. The second task was centered on the characterization and demonstration of the proposed approach in illustrative scenarios (simulated or emulated).

Reactive relay selection in underlay cognitive networks with fixed gain relays

KAUST Repository

Hussain, Syed Imtiaz

2012-06-01

Best relay selection is a bandwidth efficient technique for multiple relay environments without compromising the system performance. The problem of relay selection is more challenging in underlay cognitive networks due to strict interference constraints to the primary users. Generally, relay selection is done on the basis of maximum end-to-end signal to noise ratio (SNR). However, it requires large amounts of channel state information (CSI) at different network nodes. In this paper, we present and analyze a reactive relay selection scheme in underlay cognitive networks where the relays are operating with fixed gains near a primary user. The system model minimizes the amount of CSI required at different nodes and the destination selects the best relay on the basis of maximum relay to destination SNR. We derive close form expressions for the received SNR statistics, outage probability, bit error probability and average channel capacity of the system. Simulation results are also presented to confirm the validity of the derived expressions. © 2012 IEEE.

Supervisory Adaptive Network-Based Fuzzy Inference System (SANFIS Design for Empirical Test of Mobile Robot

Directory of Open Access Journals (Sweden)

Yi-Jen Mon

2012-10-01

Full Text Available A supervisory Adaptive Network-based Fuzzy Inference System (SANFIS is proposed for the empirical control of a mobile robot. This controller includes an ANFIS controller and a supervisory controller. The ANFIS controller is off-line tuned by an adaptive fuzzy inference system, the supervisory controller is designed to compensate for the approximation error between the ANFIS controller and the ideal controller, and drive the trajectory of the system onto a specified surface (called the sliding surface or switching surface while maintaining the trajectory onto this switching surface continuously to guarantee the system stability. This SANFIS controller can achieve favourable empirical control performance of the mobile robot in the empirical tests of driving the mobile robot with a square path. Practical experimental results demonstrate that the proposed SANFIS can achieve better control performance than that achieved using an ANFIS controller for empirical control of the mobile robot.

Effects of Unified Power Flow Controller (UPFC) on Distance Relay ...

African Journals Online (AJOL)

This paper investigates the effects of UPFC on Distance Relay tripping characteristics in Nigerian 330kV (North-Central) Network. Its operation is based on impedance measurement at the relaying point. However, the system performance is often impeded by certain operational or structural factors such as load angle, the ...

Partial relay selection in underlay cognitive networks with fixed gain relays

KAUST Repository

Hussain, Syed Imtiaz; Alouini, Mohamed-Slim; Hasna, Mazen Omar; Qaraqe, Khalid A.

2012-01-01

In a communication system with multiple cooperative relays, selecting the best relay utilizes the available spectrum more efficiently. However, selective relaying poses a different problem in underlay cognitive networks compared to the traditional cooperative networks due to interference thresholds to the primary users. In most cases, a best relay is the one which provides the maximum end-to-end signal to noise ratio (SNR). This approach needs plenty of instantaneous channel state information (CSI). The CSI burden could be reduced by partial relay selection. In this paper, a partial relay selection scheme is presented and analyzed for an underlay cognitive network with fixed gain relays operating in the vicinity of a primary user. The system model is adopted in a way that each node needs minimal CSI to perform its task. The best relay is chosen on the basis of maximum source to relay link SNR which then forwards the message to the destination. We derive closed form expressions for the received SNR distributions, system outage, probability of bit error and average channel capacity of the system. The derived results are confirmed through simulations. © 2012 IEEE.

Partial relay selection in underlay cognitive networks with fixed gain relays

KAUST Repository

Hussain, Syed Imtiaz

2012-05-01

In a communication system with multiple cooperative relays, selecting the best relay utilizes the available spectrum more efficiently. However, selective relaying poses a different problem in underlay cognitive networks compared to the traditional cooperative networks due to interference thresholds to the primary users. In most cases, a best relay is the one which provides the maximum end-to-end signal to noise ratio (SNR). This approach needs plenty of instantaneous channel state information (CSI). The CSI burden could be reduced by partial relay selection. In this paper, a partial relay selection scheme is presented and analyzed for an underlay cognitive network with fixed gain relays operating in the vicinity of a primary user. The system model is adopted in a way that each node needs minimal CSI to perform its task. The best relay is chosen on the basis of maximum source to relay link SNR which then forwards the message to the destination. We derive closed form expressions for the received SNR distributions, system outage, probability of bit error and average channel capacity of the system. The derived results are confirmed through simulations. © 2012 IEEE.

STABLE ADAPTIVE CONTROL FOR A CLASS OF NONLINEAR SYSTEMS WITHOUT USE OF A SUPERVISORY TERM IN THE CONTROL LAW

Directory of Open Access Journals (Sweden)

MOHAMED BAHITA

2012-02-01

Full Text Available In this paper, a direct adaptive control scheme for a class of nonlinear systems is proposed. The architecture employs a Gaussian radial basis function (RBF network to construct an adaptive controller. The parameters of the adaptive controller are adapted and changed according to a law derived using Lyapunov stability theory. The centres of the RBF network are adapted on line using the k-means algorithm. Asymptotic Lyapunov stability is established without the use of a supervisory (compensatory term in the control law and with the tracking errors converging to a neighbourhood of the origin. Finally, a simulation is provided to explore the feasibility of the proposed neuronal controller design method.

Opportunistic Relay Selection in Multicast Relay Networks using Compressive Sensing

KAUST Repository

Elkhalil, Khalil

2014-12-01

Relay selection is a simple technique that achieves spatial diversity in cooperative relay networks. However, for relay selection algorithms to make a selection decision, channel state information (CSI) from all cooperating relays is usually required at a central node. This requirement poses two important challenges. Firstly, CSI acquisition generates a great deal of feedback overhead (air-time) that could result in significant transmission delays. Secondly, the fed back channel information is usually corrupted by additive noise. This could lead to transmission outages if the central node selects the set of cooperating relays based on inaccurate feedback information. In this paper, we introduce a limited feedback relay selection algorithm for a multicast relay network. The proposed algorithm exploits the theory of compressive sensing to first obtain the identity of the “strong” relays with limited feedback. Following that, the CSI of the selected relays is estimated using linear minimum mean square error estimation. To minimize the effect of noise on the fed back CSI, we introduce a back-off strategy that optimally backs-off on the noisy estimated CSI. For a fixed group size, we provide closed form expressions for the scaling law of the maximum equivalent SNR for both Decode and Forward (DF) and Amplify and Forward (AF) cases. Numerical results show that the proposed algorithm drastically reduces the feedback air-time and achieves a rate close to that obtained by selection algorithms with dedicated error-free feedback channels.

Towards energy efficient operation of Heating, Ventilation and Air Conditioning systems via advanced supervisory control design

Science.gov (United States)

Oswiecinska, A.; Hibbs, J.; Zajic, I.; Burnham, K. J.

2015-11-01

This paper presents conceptual control solution for reliable and energy efficient operation of heating, ventilation and air conditioning (HVAC) systems used in large volume building applications, e.g. warehouse facilities or exhibition centres. Advanced two-level scalable control solution, designed to extend capabilities of the existing low-level control strategies via remote internet connection, is presented. The high-level, supervisory controller is based on Model Predictive Control (MPC) architecture, which is the state-of-the-art for indoor climate control systems. The innovative approach benefits from using passive heating and cooling control strategies for reducing the HVAC system operational costs, while ensuring that required environmental conditions are met.

Optimized Power Allocation and Relay Location Selection in Cooperative Relay Networks

Directory of Open Access Journals (Sweden)

Jianrong Bao

2017-01-01

Full Text Available An incremental selection hybrid decode-amplify forward (ISHDAF scheme for the two-hop single relay systems and a relay selection strategy based on the hybrid decode-amplify-and-forward (HDAF scheme for the multirelay systems are proposed along with an optimized power allocation for the Internet of Thing (IoT. Given total power as the constraint and outage probability as an objective function, the proposed scheme possesses good power efficiency better than the equal power allocation. By the ISHDAF scheme and HDAF relay selection strategy, an optimized power allocation for both the source and relay nodes is obtained, as well as an effective reduction of outage probability. In addition, the optimal relay location for maximizing the gain of the proposed algorithm is also investigated and designed. Simulation results show that, in both single relay and multirelay selection systems, some outage probability gains by the proposed scheme can be obtained. In the comparison of the optimized power allocation scheme with the equal power allocation one, nearly 0.1695 gains are obtained in the ISHDAF single relay network at a total power of 2 dB, and about 0.083 gains are obtained in the HDAF relay selection system with 2 relays at a total power of 2 dB.

Threshold-Based Relay Selection for Detect-and-Forward Relaying in Cooperative Wireless Networks

Directory of Open Access Journals (Sweden)

Fan Yijia

2010-01-01

Full Text Available This paper studies two-hop cooperative demodulate-and-forward relaying using multiple relays in wireless networks. A threshold based relay selection scheme is considered, in which the reliable relays are determined by comparing source-relay SNR to a threshold, and one of the reliable relays is selected by the destination based on relay-destination SNR. The exact bit error rate of this scheme is derived, and a simple threshold function is proposed. It is shown that the network achieves full diversity order ( under the proposed threshold, where is the number of relays in the network. Unlike some other full diversity achieving protocols in the literature, the requirement that the instantaneous/average SNRs of the source-relay links be known at the destination is eliminated using the appropriate SNR threshold.

Telecommunications Relay Services

Science.gov (United States)

... Home » Health Info » Hearing, Ear Infections, and Deafness Telecommunications Relay Services On this page: What are telecommunication ... additional information about telecommunication relay services? What are telecommunication relay services? Title IV of the Americans with ...

Reactive relay selection in underlay cognitive networks with fixed gain relays

KAUST Repository

Hussain, Syed Imtiaz; Alouini, Mohamed-Slim; Qaraqe, Khalid A.; Hasna, Mazen Omar

2012-01-01

Best relay selection is a bandwidth efficient technique for multiple relay environments without compromising the system performance. The problem of relay selection is more challenging in underlay cognitive networks due to strict interference

Individual Channel Estimation in a Diamond Relay Network Using Relay-Assisted Training

Directory of Open Access Journals (Sweden)

Xianwen He

2017-01-01

Full Text Available We consider the training design and channel estimation in the amplify-and-forward (AF diamond relay network. Our strategy is to transmit the source training in time-multiplexing (TM mode while each relay node superimposes its own relay training over the amplified received data signal without bandwidth expansion. The principal challenge is to obtain accurate channel state information (CSI of second-hop link due to the multiaccess interference (MAI and cooperative data interference (CDI. To maintain the orthogonality between data and training, a modified relay-assisted training scheme is proposed to migrate the CDI, where some of the cooperative data at the relay are discarded to accommodate relay training. Meanwhile, a couple of optimal zero-correlation zone (ZCZ relay-assisted sequences are designed to avoid MAI. At the destination node, the received signals from the two relay nodes are combined to achieve spatial diversity and enhanced data reliability. The simulation results are presented to validate the performance of the proposed schemes.

Efficient incremental relaying

KAUST Repository

Fareed, Muhammad Mehboob

2013-07-01

We propose a novel relaying scheme which improves the spectral efficiency of cooperative diversity systems by utilizing limited feedback from destination. Our scheme capitalizes on the fact that relaying is only required when direct transmission suffers deep fading. We calculate the packet error rate for the proposed efficient incremental relaying scheme with both amplify and forward and decode and forward relaying. Numerical results are also presented to verify their analytical counterparts. © 2013 IEEE.

Idaho National Laboratory Supervisory Control and Data Acquisition Intrusion Detection System (SCADA IDS)

Energy Technology Data Exchange (ETDEWEB)

Jared Verba; Michael Milvich

2008-05-01

Current Intrusion Detection System (IDS) technology is not suited to be widely deployed inside a Supervisory, Control and Data Acquisition (SCADA) environment. Anomaly- and signature-based IDS technologies have developed methods to cover information technology-based networks activity and protocols effectively. However, these IDS technologies do not include the fine protocol granularity required to ensure network security inside an environment with weak protocols lacking authentication and encryption. By implementing a more specific and more intelligent packet inspection mechanism, tailored traffic flow analysis, and unique packet tampering detection, IDS technology developed specifically for SCADA environments can be deployed with confidence in detecting malicious activity.

Computer-based supervisory control and data acquisition system for the radioactive waste evaporator

International Nuclear Information System (INIS)

Pope, N.G.; Schreiber, S.B.; Yarbro, S.L.; Gomez, B.G.; Nekimken, H.L.; Sanchez, D.E.; Bibeau, R.A.; Macdonald, J.M.

1994-12-01

The evaporator process at TA-55 reduces the amount of transuranic liquid radioactive waste by separating radioactive salts from relatively low-level radioactive nitric acid solution. A computer-based supervisory control and data acquisition (SCADA) system has been installed on the process that allows the operators to easily interface with process equipment. Individual single-loop controllers in the SCADA system allow more precise process operation with less human intervention. With this system, process data can be archieved in computer files for later analysis. Data are distributed throughout the TA-55 site through a local area network so that real-time process conditions can be monitored at multiple locations. The entire system has been built using commercially available hardware and software components

Distributed Antenna Channels with Regenerative Relaying: Relay Selection and Asymptotic Capacity

Directory of Open Access Journals (Sweden)

Aitor del Coso

2007-11-01

Full Text Available Multiple-input-multiple-output (MIMO techniques have been widely proposed as a means to improve capacity and reliability of wireless channels, and have become the most promising technology for next generation networks. However, their practical deployment in current wireless devices is severely affected by antenna correlation, which reduces their impact on performance. One approach to solve this limitation is relaying diversity. In relay channels, a set of N wireless nodes aids a source-destination communication by relaying the source data, thus creating a distributed antenna array with uncorrelated path gains. In this paper, we study this multiple relay channel (MRC following a decode-and-forward (D&F strategy (i.e., regenerative forwarding, and derive its achievable rate under AWGN. A half-duplex constraint on relays is assumed, as well as distributed channel knowledge at both transmitter and receiver sides of the communication. For this channel, we obtain the optimum relay selection algorithm and the optimum power allocation within the network so that the transmission rate is maximized. Likewise, we bound the ergodic performance of the achievable rate and derive its asymptotic behavior in the number of relays. Results show that the achievable rate of regenerative MRC grows as the logarithm of the Lambert W function of the total number of relays, that is, 𝒞=log⁡2(W0(N. Therefore, D&F relaying, cannot achieve the capacity of actual MISO channels.

Supervisory System and Multivariable Control Applying Weighted Fuzzy-PID Logic in an Alcoholic Fermentation Process

Directory of Open Access Journals (Sweden)

Márcio Mendonça

2015-10-01

Full Text Available In this work, it is analyzed a multivariate system control of an alcoholic fermentation process with no minimum phase. The control is made with PID classic controllers associated with a supervisory system based on Fuzzy Systems. The Fuzzy system, a priori, send set-points to PID controllers, but also adds protection functions, such as if the biomass valued is at zero or very close. The Fuzzy controller changes the campaign to prevent or mitigate the paralyzation of the process. Three control architectures based on Fuzzy Control Systems are presented and compared in performance with classic control in different campaigns. The third architecture, in particular, adds an adaptive function. A brief summary of Fuzzy theory and correlated works will be presented. And, finally simulations results, conclusions and future works end the article.

Opportunistic relaying in multipath and slow fading channel: Relay selection and optimal relay selection period

KAUST Repository

Sungjoon Park,; Stark, Wayne E.

2011-01-01

In this paper we present opportunistic relay communication strategies of decode and forward relaying. The channel that we are considering includes pathloss, shadowing, and fast fading effects. We find a simple outage probability formula

A Safe Supervisory Flight Control Scheme in the Presence of Constraints and Anomalies

Directory of Open Access Journals (Sweden)

Franzè Giuseppe

2015-03-01

Full Text Available In this paper the hybrid supervisory control architecture developed by Famularo et al. (2011 for constrained control systems is adopted with the aim to improve safety in aircraft operations when critical events like command saturations or unpredicted anomalies occur. The capabilities of a low-computational demanding predictive scheme for the supervision of non-linear dynamical systems subject to sudden switchings amongst operating conditions and time-varying constraints are exploited in the flight control systems framework. The strategy is based on command governor ideas and is tailored to jointly take into account time-varying set-points/constraints. Unpredictable anomalies in the nominal plant behaviour, whose models fall in the category of time-varying constraints, can also be tolerated by the control scheme. In order to show the effectiveness of the proposed approach, simulations both on a high altitude performance demonstrator unmanned aircraft with redundant control surfaces and the P92 general aviation aircraft are discussed.

Performance limitations of relay neurons.

Directory of Open Access Journals (Sweden)

Rahul Agarwal

Full Text Available Relay cells are prevalent throughout sensory systems and receive two types of inputs: driving and modulating. The driving input contains receptive field properties that must be transmitted while the modulating input alters the specifics of transmission. For example, the visual thalamus contains relay neurons that receive driving inputs from the retina that encode a visual image, and modulating inputs from reticular activating system and layer 6 of visual cortex that control what aspects of the image will be relayed back to visual cortex for perception. What gets relayed depends on several factors such as attentional demands and a subject's goals. In this paper, we analyze a biophysical based model of a relay cell and use systems theoretic tools to construct analytic bounds on how well the cell transmits a driving input as a function of the neuron's electrophysiological properties, the modulating input, and the driving signal parameters. We assume that the modulating input belongs to a class of sinusoidal signals and that the driving input is an irregular train of pulses with inter-pulse intervals obeying an exponential distribution. Our analysis applies to any [Formula: see text] order model as long as the neuron does not spike without a driving input pulse and exhibits a refractory period. Our bounds on relay reliability contain performance obtained through simulation of a second and third order model, and suggest, for instance, that if the frequency of the modulating input increases or the DC offset decreases, then relay increases. Our analysis also shows, for the first time, how the biophysical properties of the neuron (e.g. ion channel dynamics define the oscillatory patterns needed in the modulating input for appropriately timed relay of sensory information. In our discussion, we describe how our bounds predict experimentally observed neural activity in the basal ganglia in (i health, (ii in Parkinson's disease (PD, and (iii in PD during

Relay Selection for Cooperative Relaying in Wireless Energy Harvesting Networks

Science.gov (United States)

Zhu, Kaiyan; Wang, Fei; Li, Songsong; Jiang, Fengjiao; Cao, Lijie

2018-01-01

Energy harvesting from the surroundings is a promising solution to provide energy supply and extend the life of wireless sensor networks. Recently, energy harvesting has been shown as an attractive solution to prolong the operation of cooperative networks. In this paper, we propose a relay selection scheme to optimize the amplify-and-forward (AF) cooperative transmission in wireless energy harvesting cooperative networks. The harvesting energy and channel conditions are considered to select the optimal relay as cooperative relay to minimize the outage probability of the system. Simulation results show that our proposed relay selection scheme achieves better outage performance than other strategies.

Relay Selection and Resource Allocation in One-Way and Two-Way Cognitive Relay Networks

KAUST Repository

Alsharoa, Ahmad M.

2013-05-08

In this work, the problem of relay selection and resource power allocation in one- way and two-way cognitive relay networks using half duplex channels with different relaying protocols is investigated. Optimization problems for both single and multiple relay selection that maximize the sum rate of the secondary network without degrading the quality of service of the primary network by respecting a tolerated interference threshold were formulated. Single relay selection and optimal power allocation for two-way relaying cognitive radio networks using decode-and-forward and amplify-and-forward protocols were studied. Dual decomposition and subgradient methods were used to find the optimal power allocation. The transmission process to exchange two different messages between two transceivers for two-way relaying technique takes place in two time slots. In the first slot, the transceivers transmit their signals simultaneously to the relay. Then, during the second slot the relay broadcasts its signal to the terminals. Moreover, improvement of both spectral and energy efficiency can be achieved compared with the one-way relaying technique. As an extension, a multiple relay selection for both one-way and two-way relaying under cognitive radio scenario using amplify-and-forward were discussed. A strong optimization tool based on genetic and iterative algorithms was employed to solve the 
formulated optimization problems for both single and multiple relay selection, where discrete relay power levels were considered. Simulation results show that the practical and low-complexity heuristic approaches achieve almost the same performance of the optimal relay selection schemes either with discrete or continuous power distributions while providing a considerable saving in terms of computational complexity.

Location-based Relay Selection and Power Adaptation Enabling Simultaneous Transmissions

DEFF Research Database (Denmark)

Nielsen, Jimmy Jessen; Madsen, Tatiana Kozlova; Schwefel, Hans-Peter

2010-01-01

Relaying is a well known technique to extend coverage and improve conditions for nodes in the outer coverage region. In this paper we propose a relaying scheme that exploits the spatial separation of relay and destination pairs to improve throughput by allowing simultaneous transmissions....... The proposed scheme is a cross-layer optimization for two-hop relaying that uses position information to jointly optimize relay selection and relay transmit power, maximizing Medium Access Control layer throughput. Further, in order to calculate the expected throughput, we apply a probabilistic model...... that takes into account MAC retransmissions and timing behavior of the IEEE 802.11 Distributed Coordination Function mode. Our results show an increase in throughput of approximately 20% is achievable for the proposed scheme when compared to two-hop relaying in the analyzed scenario....

What happens at work stays at work? Workplace supervisory social interactions and blood pressure outcomes.

Science.gov (United States)

Wong, Jennifer H K; Kelloway, E Kevin

2016-04-01

We investigated the relationship between workplace supervisory social interactions and blood pressure outcomes using hourly diary entries and ambulatory blood pressure data from an experience sampling study of 55 long-term care employees. After accounting for relevant cardiovascular controls, significant effects of supervisory interactions on cardiovascular reactivity and recovery were found. Multilevel analyses revealed that negatively perceived supervisory interactions predicted higher systolic blood pressure at work (B = -1.59, p pressure recovery after work (B = -14.52, p < .05, N = 33). Specifically, negatively perceived supervisory interactions at work predicted poorer cardiovascular recovery after work. Suggestions for improving practices in organizations and in experience sampling research are discussed. (c) 2016 APA, all rights reserved).

Joint source and relay optimization for interference MIMO relay networks

Science.gov (United States)

Khandaker, Muhammad R. A.; Wong, Kai-Kit

2017-12-01

This paper considers multiple-input multiple-output (MIMO) relay communication in multi-cellular (interference) systems in which MIMO source-destination pairs communicate simultaneously. It is assumed that due to severe attenuation and/or shadowing effects, communication links can be established only with the aid of a relay node. The aim is to minimize the maximal mean-square-error (MSE) among all the receiving nodes under constrained source and relay transmit powers. Both one- and two-way amplify-and-forward (AF) relaying mechanisms are considered. Since the exactly optimal solution for this practically appealing problem is intractable, we first propose optimizing the source, relay, and receiver matrices in an alternating fashion. Then we contrive a simplified semidefinite programming (SDP) solution based on the error covariance matrix decomposition technique, avoiding the high complexity of the iterative process. Numerical results reveal the effectiveness of the proposed schemes.

Autonomous Supervisory Engine for Multi-Spacecraft Formation Flying, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — The overall goal of this project is to develop an onboard, autonomous Multi-spacecraft Supervisory Engine (MSE) for formation-flying guidance, navigation and control...

A fuzzy quality function deployment approach to improve a component of a supervisory control and data acquisition system

OpenAIRE

Cristea Ciprian; Saşa Ciprian; Cristea Maria

2017-01-01

Monitoring and control of electric transformer stations, frequently spread out over small or large geographical areas, are achieved with supervisory control and data acquisition (SCADA). Quality function deployment (QFD) is a valuable analyzing tool in product design and development. To solve the uncertainty or inherent imprecision in QFD, many researchers have applied the fuzzy set theory to QFD and have developed various fuzzy QFD approaches. The literature regarding applying fuzzy QFD for ...

Alternate transmission relaying based on interference alignment in 3-relay half-duplex MIMO systems

KAUST Repository

Park, Seongho; Park, Kihong; Ko, Youngchai; Alouini, Mohamed-Slim

2012-01-01

In a half-duplex relaying, the capacity pre-log factor 1/2 is a major drawback in spectral efficiency. This paper proposes a linear precoding/decoding scheme and an alternate relaying protocol in a dual-hop half-duplex system where three relays help the communication between the source and the destination. In our proposed scheme, we consider a phase incoherent method in relays in which the source alternately transmits message signals to the different relays. In addition, we propose a linear interference alignment scheme which can suppress the inter-relay interference resulting from the phase incoherence of relaying. Based on our analysis of degrees of freedom and our simulation results, we show that our proposed scheme achieves additional degrees of freedom compared to the conventional half-duplex relaying. © 2012 IEEE.

Alternate transmission relaying based on interference alignment in 3-relay half-duplex MIMO systems

KAUST Repository

Park, Seongho

2012-09-01

In a half-duplex relaying, the capacity pre-log factor 1/2 is a major drawback in spectral efficiency. This paper proposes a linear precoding/decoding scheme and an alternate relaying protocol in a dual-hop half-duplex system where three relays help the communication between the source and the destination. In our proposed scheme, we consider a phase incoherent method in relays in which the source alternately transmits message signals to the different relays. In addition, we propose a linear interference alignment scheme which can suppress the inter-relay interference resulting from the phase incoherence of relaying. Based on our analysis of degrees of freedom and our simulation results, we show that our proposed scheme achieves additional degrees of freedom compared to the conventional half-duplex relaying. © 2012 IEEE.

Autocommander: A Supervisory Controller for Integrated Guidance and Control for the 2nd Generation Reusable Launch Vehicle

Science.gov (United States)

Fisher, J. E.; Lawrence, D. A.; Zhu, J. J.; Jackson, Scott (Technical Monitor)

2002-01-01

This paper presents a hierarchical architecture for integrated guidance and control that achieves risk and cost reduction for NASA's 2d generation reusable launch vehicle (RLV). Guidance, attitude control, and control allocation subsystems that heretofore operated independently will now work cooperatively under the coordination of a top-level autocommander. In addition to delivering improved performance from a flight mechanics perspective, the autocommander is intended to provide an autonomous supervisory control capability for traditional mission management under nominal conditions, G&C reconfiguration in response to effector saturation, and abort mode decision-making upon vehicle malfunction. This high-level functionality is to be implemented through the development of a relational database that is populated with the broad range of vehicle and mission specific data and translated into a discrete event system model for analysis, simulation, and onboard implementation. A Stateflow Autocoder software tool that translates the database into the Stateflow component of a Matlab/Simulink simulation is also presented.

Coordinated Direct and Relay Transmission with Linear Non-Regenerative Relay Beamforming

DEFF Research Database (Denmark)

Sun, Fan; De Carvalho, Elisabeth; Popovski, Petar

2012-01-01

Joint processing of multiple communication flows in wireless systems has given rise to a number of novel transmission techniques, notably the two-way relaying, but also more general traffic scenarios, such as coordinated direct and relay (CDR) transmissions. In a CDR scheme the relay has a central...... role in managing the interference and boosting the overall system performance. In this letter we consider the case in which an amplify-and-forward relay has multiple antennas and can use beamforming to support the coordinated transmissions. We focus on one representative traffic type with one uplink...... user and one downlink user. Two different criteria for relay beamforming are analyzed: maximal weighted sum-rate and maximization of the worst-case weighted SNR. We propose iterative optimal solutions, as well as low-complexity near-optimal solutions....

Radioisotope relay instrument

International Nuclear Information System (INIS)

Pozdnyakov, V.N.; Sazonov, O.L.; Taksar, I.M.; Tesnavs, Eh.R.; Yanushkovskij, V.A.

1974-01-01

The paper describes a radioisotope relay device containing a radiation source, a detector, an electronic relay block with a comparative threshold mechanism. The device differs from previously known ones in that, for the purpose of increasing stability and speed of action, the electronic relay block is a separate unit and contains two threshold pulse generators which are joined up, across series-connected ''and'' and ''or'' elements, with one of the inputs of the comparative threshold mechanism, whose second input is connected with a detector and whose outputs are connected with a relay element connected by feedback with the above-mentioned ''and'' elements. (author)

30 CFR 77.1703 - First-Aid training; supervisory employees.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false First-Aid training; supervisory employees. 77... UNDERGROUND COAL MINES Miscellaneous § 77.1703 First-Aid training; supervisory employees. The mine operator shall conduct first-aid training courses for selected supervisory employees at the mine. Within 60 days...

Decode and Zero-Forcing Forward Relaying with Relay Selection in Cognitive Radio Systems

KAUST Repository

Park, Kihong

2014-05-01

In this paper, we investigate a cognitive radio (CR) relay network with multiple relay nodes that help forwarding the signal of CR users. Best relay selection is considered to take advantage of its low complexity of implementation. When the primary user (PU) is located close to the relay nodes, the performance of the secondary network is severely degraded due to the interference power constraint during the transmission in the second hop. We propose a decode and zero-forcing forward scheme to suppress the interference power at the relay nodes and analyze the statistics of the end-to-end signal-to-noise ratio when the relay nodes are located arbitrarily and experience therefore non-identical Rayleigh fading channels. Numerical results validate our theoretical results and show that our proposed scheme improves the performance of the CR network when the PU is close to the relay nodes. © 2014 IEEE.

An assessment of fire vulnerability for aged electrical relays

International Nuclear Information System (INIS)

Vigil, R.A.; Nowlen, S.P.

1995-03-01

There has been some concern that, as nuclear power plants age, protective measures taken to control and minimize the impact of fire may become ineffective, or significantly less effective, and hence result in an increased fire risk. One objective of the Fire Vulnerability of Aged Electrical Components Program is to assess the effects of aging and service wear on the fire vulnerability of electrical equipment. An increased fire vulnerability of components may lead to an overall increase in fire risk to the plant. Because of their widespread use in various electrical safety systems, electromechanical relays were chosen to be the initial components for evaluation. This test program assessed the impact of operational and thermal aging on the vulnerability of these relays to fire-induced damage. Only thermal effects of a fire were examined in this test program. The impact of smoke, corrosive materials, or fire suppression effects on relay performance were not addressed in this test program. The purpose of this test program was to assess whether the fire vulnerability of electrical relays increased with aging. The sequence followed for the test program was to: identify specific relay types, develop three fire scenarios, artificially age several relays, test the unaged and aged relays in the fire exposure scenarios, and compare the results. The relays tested were Agastat GPI, General Electric (GE) HMA, HGA, and HFA. At least two relays of each type were artificially aged and at least two relays of each type were new. Relays were operationally aged by cycling the relay under rated load for 2,000 operations. These relays were then thermally aged for 60 days with their coil energized

On the achievable degrees of freedom of alternate MIMO relaying with multiple AF relays

KAUST Repository

Park, Kihong

2012-03-01

In this paper, we consider a two-hop relaying network where one source, one destination, and multiple amplify-and-forward (AF) relays equipped with M antennas operate in a half-duplex mode. In order to compensate for the inherent loss of capacity pre-log factor of 1/2 due to half-duplex relaying, we propose a new transmission protocol which combines alternate relaying and inter-relay interference alignment. We prove that the proposed scheme can (i) exploits M degrees of freedom (DOFs) and (ii) perfectly recover the pre-log factor loss if the number of relays is at least six. From our selected numerical results, we show that our proposed scheme gives significant improvement over conventional AF relaying which offers only M/2 DOFs. © 2012 IEEE.

Low-Cost Control System Built Upon Consumer-Based Electronics For Supervisory Control Of A Gas-Operated Heat Pump

Energy Technology Data Exchange (ETDEWEB)

Wetherington Jr, G Randall [ORNL; Vineyard, Edward Allan [ORNL; Mahderekal, Isaac [ORNL; Abu-Heiba, Ahmad [ORNL

2017-06-01

A preliminary evaluation of the performance of a consumer-based control system was conducted by the Oak Ridge National Laboratory (ORNL) and Southwest Gas as part of a cooperative research and development agreement (CRADA) authorized by the Department of Energy (DOE) (Mahderekal et al. (2013). The goal of the research was to evaluate the low-cost approach as a solution for implementing a supervisory control system for a residential gas-operated heat pump. The design incorporated two consumer-based micro-controllers; the Arduino Mega-2650 and the BeagleBone (white). Ten five-ton heat pump systems were designed, fabricated, and operationally tested in the Las Vega NV region. A robust data set was produced that allowed detailed assessment of the reliability and the operational perfromance of the newly developed control system. Experiences gained from the test provided important points of improvement for subsequent evolution of the heat pump technology.

Perancangan Sistem Pemantauan Pengendali Suhu pada Stirred Tank Heater menggunakan Supervisory Control and Data Acquisition (SCADA

Directory of Open Access Journals (Sweden)

Ike Bayusari

2013-04-01

Full Text Available This paper discusses design of a suhue control monitoring system in stirred tank heater system that has an important function in industrial processes. Monitoring of suhue control system in stirred tank heater is designed using Supervisory Control and Data Acquisition (SCADA that control function of industrial processes. While the actuator to be controlled is the position of burner openings, so that the heat can be adjusted to meet a predetermined set-point. The suhue controller that is also used as a Remote Terminal Unit (RTU is Programmable Logic Controller (PLC. The testing result showed on SCADA system was quite good, where the average percentage of deviation for testing of set-point data was 0.76687%, and the percentage of deviation for testing of suhue data was 0.082%.

Modeling and Simulation of Out of Step Blocking Relay for

Directory of Open Access Journals (Sweden)

Ahmed A. Al Adwani

2013-05-01

Full Text Available  This paper investigates a power swing effect on a distance protection relay performance installed on (HV/EHV transmission line as well as power system stability. A conventional distance relay can’t properly operate under transient stability conditions; therefore, it cause mol-operation, and it will adversely impact on its trip signals. To overcome this problem, the Out Of Step (OOS relay has modeled and simulated to joint with distance relay to supervise and control on its trip signals response. The setting characteristics technique of the OOS based on concentric polygons scheme method to detect power swing under transient stability situation.         This study ia a modeling and simulating using (Maltab\\ Simulink software. A Two relays had been  performed   and  tested  with  two equivalents network connected to ends.      The results of this study showed an activity and reliability of this way to control the distance relay response under a transient stability conditions and it indicated the possibility to find out faults which may occur at period of power swing

Relay Precoder Optimization in MIMO-Relay Networks With Imperfect CSI

KAUST Repository

Pandarakkottilil, Ubaidulla

2011-11-01

In this paper, we consider robust joint designs of relay precoder and destination receive filters in a nonregenerative multiple-input multiple-output (MIMO) relay network. The network consists of multiple source-destination node pairs assisted by a MIMO-relay node. The channel state information (CSI) available at the relay node is assumed to be imperfect. We consider robust designs for two models of CSI error. The first model is a stochastic error (SE) model, where the probability distribution of the CSI error is Gaussian. This model is applicable when the imperfect CSI is mainly due to errors in channel estimation. For this model, we propose robust minimum sum mean square error (SMSE), MSE-balancing, and relay transmit power minimizing precoder designs. The next model for the CSI error is a norm-bounded error (NBE) model, where the CSI error can be specified by an uncertainty set. This model is applicable when the CSI error is dominated by quantization errors. In this case, we adopt a worst-case design approach. For this model, we propose a robust precoder design that minimizes total relay transmit power under constraints on MSEs at the destination nodes. We show that the proposed robust design problems can be reformulated as convex optimization problems that can be solved efficiently using interior-point methods. We demonstrate the robust performance of the proposed design through simulations. © 2011 IEEE.

Supervisory Presentation for Research, Information, Integration and Testing (SPRINT)

Science.gov (United States)

2015-03-29

in Microsoft Visual Studio and several third party developer libraries (See Figure 4). All distributed laboratory sites have similar hardware...Testing (SPRINT). 15. SUBJECT TERMS Supervisory Control, Multi-Modal Interfaces, Scalable Interfaces, Advanced Visualization , Augmented Symbology 16...23 Figure 9. Fusion Visual Framework Components

Preventive maintenance basis: Volume 30 -- Relays -- control. Final report

International Nuclear Information System (INIS)

Worledge, D.; Hinchcliffe, G.

1998-07-01

US nuclear power plants are implementing preventive maintenance (PM) tasks with little documented basis beyond fundamental vendor information to support the tasks or their intervals. The Preventive Maintenance Basis project provides utilities with the technical basis for PM tasks and task intervals associated with 40 specific components such as valves, electric motors, pumps, and HVAC equipment. This document provides a program of preventive maintenance tasks suitable for application to control relays. The PM tasks that are recommended provide a cost-effective way to intercept the causes and mechanisms that lead to degradation and failure. They can be used in conjunction with material from other sources, to develop a complete PM program or to improve an existing program

Decode and Zero-Forcing Forward Relaying with Relay Selection in Cognitive Radio Systems

KAUST Repository

Park, Kihong; Alouini, Mohamed-Slim

2014-01-01

In this paper, we investigate a cognitive radio (CR) relay network with multiple relay nodes that help forwarding the signal of CR users. Best relay selection is considered to take advantage of its low complexity of implementation. When the primary

Relay Precoder Optimization in MIMO-Relay Networks With Imperfect CSI

KAUST Repository

Pandarakkottilil, Ubaidulla; Chockalingam, A.

2011-01-01

In this paper, we consider robust joint designs of relay precoder and destination receive filters in a nonregenerative multiple-input multiple-output (MIMO) relay network. The network consists of multiple source-destination node pairs assisted by a

CERN Relay Race

CERN Document Server

CERN Running Club

2010-01-01

The CERN relay race will take place around the Meyrin site on Thursday 20 May, starting at 12.15. If possible, please avoid driving on the site during this 20-minute period. If you do meet runners while driving your car, please STOP until they have all passed. Thank you for your cooperation. Details on the route, and how to register your team for the relay race, can be found at: https://espace.cern.ch/Running-Club/CERN-Relay

Alternate MIMO relaying with three AF relays using interference alignment

KAUST Repository

Park, Kihong; Alouini, Mohamed-Slim

2012-01-01

In this paper, we study a two-hop half-duplex relaying network with one source, one destination, and three amplify-and-forward (AF) relays equipped with M antennas each. We consider alternate transmission to compensate for the inherent loss

Developing a Domain Model for Relay Circuits

DEFF Research Database (Denmark)

Haxthausen, Anne Elisabeth

2009-01-01

In this paper we stepwise develop a domain model for relay circuits as used in railway control systems. First we provide an abstract, property-oriented model of networks consisting of components that can be glued together with connectors. This model is strongly inspired by a network model...... for railways madeby Bjørner et.al., however our model is more general: the components can be of any kind and can later be refined to e.g. railway components or circuit components. Then we show how the abstract network model can be refined into an explicit model for relay circuits. The circuit model describes...... the statics as well as the dynamics of relay circuits, i.e. how a relay circuit can be composed legally from electrical components as well as how the components may change state over time. Finally the circuit model is transformed into an executable model, and we show how a concrete circuit can be defined...

A relay rack for a control and protection system for nuclear reactors

International Nuclear Information System (INIS)

Miyata, Yasuyuki; Oda, Noriaki; Akiyama, Toyoshi

1975-01-01

It is obvious that all the equipment in the various systems that constitute a nuclear power plant must exhibit the highest levels of reliability, but the reactor control and protection system is of vital importance, and thus it requires a particularly thorough approach, incorporating redundancy, independence and separation. The paper describes the functions, construction and specifications of the relay rack - one of the most important items of equipment for reactor control and protection in a generating facility using a pressurized-water reactor - and it gives details of the extent to which these three requirements are satisfied. (author)

80537 based distance relay

DEFF Research Database (Denmark)

Pedersen, Knud Ole Helgesen

1999-01-01

A method for implementing a digital distance relay in the power system is described.Instructions are given on how to program this relay on a 80537 based microcomputer system.The problem is used as a practical case study in the course 53113: Micocomputer applications in the power system.The relay...

Traffic supervisory/control system for Kobe-Awaji- Naruto expressway of Honshu-Shikoku Bridge Authority; Honshu Shikoku Renrakukyo Kodan nonyu no Kobe Awaji Naruto jidoshado kotsu kansei shisetsu seigyo system

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-03-01

Toshiba delivered the traffic supervisory/control system for Kobe-Awaji-Naruto expressway of Honshu-Shikoku Bridge Authority opened in May 1998. This traffic supervisory system rapidly exactly collects and services the information on the expressway of 89km including Akashi Kaikyo bridge and O-Naruto bridge. The facility control system totally efficiently maintains and controls various facilities for lighting and air circulation of tunnels on the expressway. The previous control system transmitted road information on traffic volume and traffic congestion to offices by using specific lines and terminals, while this system with a monitoring function using intranet can easily service such information by existing PCs. (translated by NEDO)

Traffic supervisory/control system for Kobe-Awaji- Naruto expressway of Honshu-Shikoku Bridge Authority. Honshu Shikoku Renrakukyo Kodan nonyu no Kobe Awaji Naruto jidoshado kotsu kansei shisetsu seigyo system

Energy Technology Data Exchange (ETDEWEB)

1999-03-01

Toshiba delivered the traffic supervisory/control system for Kobe-Awaji-Naruto expressway of Honshu-Shikoku Bridge Authority opened in May 1998. This traffic supervisory system rapidly exactly collects and services the information on the expressway of 89km including Akashi Kaikyo bridge and O-Naruto bridge. The facility control system totally efficiently maintains and controls various facilities for lighting and air circulation of tunnels on the expressway. The previous control system transmitted road information on traffic volume and traffic congestion to offices by using specific lines and terminals, while this system with a monitoring function using intranet can easily service such information by existing PCs. (translated by NEDO)

Chiral relay: a novel strategy for the control and amplification of enantioselectivity in chiral Lewis acid promoted reactions.

Science.gov (United States)

Corminboeuf, Olivier; Quaranta, Laura; Renaud, Philippe; Liu, Mei; Jasperse, Craig P; Sibi, Mukund P

2003-01-03

Chiral Lewis acid catalysis has emerged as one of the premiere method to control stereochemistry. Much effort has gone into the design of superior ligands with increasing steric extension to shield distant reactive sites. We report here an alternative and complementary approach based on a "chiral relay". This strategy focuses on the improved design of achiral templates which may relay and amplify the stereochemistry from ligands. The essence of this strategy is that the chiral Lewis acid would effectively convert an achiral template into a chiral non-racemic template. This approach combines the advantages of enantioselective catalysis (substoichiometric amount of the chiral inducer) with the ones of chiral auxiliary control (efficient and predictable stereocontrol).

Relay Selection and Resource Allocation in One-Way and Two-Way Cognitive Relay Networks

KAUST Repository

Alsharoa, Ahmad M.

2013-01-01

In this work, the problem of relay selection and resource power allocation in one- way and two-way cognitive relay networks using half duplex channels with different relaying protocols is investigated. Optimization problems for both single

A genetic algorithm for multiple relay selection in two-way relaying cognitive radio networks

KAUST Repository

Alsharoa, Ahmad M.; Ghazzai, Hakim; Alouini, Mohamed-Slim

2013-01-01

In this paper, we investigate a multiple relay selection scheme for two-way relaying cognitive radio networks where primary users and secondary users operate on the same frequency band. More specifically, cooperative relays using Amplifyand- Forward

Efficient incremental relaying

KAUST Repository

Fareed, Muhammad Mehboob; Alouini, Mohamed-Slim

2013-01-01

We propose a novel relaying scheme which improves the spectral efficiency of cooperative diversity systems by utilizing limited feedback from destination. Our scheme capitalizes on the fact that relaying is only required when direct transmission

Investigation of crew performance in a multi-vehicle supervisory control task

Science.gov (United States)

Miller, R. A.; Plamondon, B. D.; Jagacinski, R. J.; Kirlik, A. C.

1986-01-01

Crew information processing and decision making in a supervisory control task which is loosely based on the mission of future generation helicopters is measured and represented. Subjects control the motion and activities of their own vehicle and direct the activities of four additional craft. The task involves searching an uncertain environment for cargo and enemies, returning cargo to home base and destroying enemies while attempting to avoid destruction of the scout and the supervised vehicles. A series of experiments with two-person crews and one-person crews were performed. Resulting crew performance was modeled with the objective of describing and understanding the information processing strategies utilized. Of particular interest are problem simplification strategies under time stress and high work load, simplification and compensation in the one-person cases, crew coordination in the two-person cases, and the relationship between strategy and errors in all cases. The results should provide some insight into the effective use of aids, particularly aids based on artificial intelligence, for similar tasks. The simulation is described which is used for the study and some preliminary results from the first two-person crew study are discussed.

Conditions for settling liquid levels by means of gamma-ray relay control

Energy Technology Data Exchange (ETDEWEB)

Wakabayashi, N [Kobe Univ. (Japan). Faculty of Engineering

1976-03-01

Using a control action which consists of infusion and exhaust at constant speeds and a neutral zone to maintain liquid levels within a given range, a gamma-ray source, a detector, and two relays at the upper and lower limits of the counting rate were provided. The optimum condition in this case is discussed and confirmed experimentally. Since a counting rate-meter has a time constant and its output is subject to the statistical fluctuation, the liquid level may overrun the opposite limit, move again after settling within the range, or drift far out of the range by a load before actuation of the relay. Formulas are derived providing the conditions such that these phenomena will not occur more frequently than a tolerant probability. These give the relations between the counting rates at the upper and lower limits, the time constant of the rate-meter, the multipliers of the standard deviations of the counting rates, the infusing and exhausting speeds, and the hysteresis widths of the limiting relays. Since it can be said that the first two of the five quantities should be smaller and the next two greater, the optimum condition can be determined from the formulas. When the infusing and exhausting speeds are the same and the hysteresis widths are equal, the formulas show that the optimum is a case where the ratio of the counting rates at the two limits, which is taken smaller than unity, is small, and where each hysteresis width is equal to 0.34 times the difference between the two counting rates, almost regardless of the value of their ratio. The above-mentioned deductions were examined in a system constructed with a backscattered gamma-ray type level gauge and a controller for infusion and exhaust of water. Its results almost agreed with those of the deductions when the multipliers of the standard deviations are substituted for by 2.

Outage performance of two-way DF relaying systems with a new relay selection metric

KAUST Repository

Hyadi, Amal; Benjillali, Mustapha; Alouini, Mohamed-Slim

2012-01-01

This paper investigates a new constrained relay selection scheme for two-way relaying systems where two end terminals communicate simultaneously via a relay. The introduced technique is based on the maximization of the weighted sum rate of both

76 FR 24442 - Structure and Practices of the Video Relay Service Program; Telecommunications Relay Services and...

Science.gov (United States)

2011-05-02

... same meaning as the terms ``small business,'' ``small organization,'' and ``small governmental...] Structure and Practices of the Video Relay Service Program; Telecommunications Relay Services and Speech-to... Commission's Structure and Practices of the Video Relay Service Program; Telecommunications Relay Services...

Board of Directors or Supervisory Board

DEFF Research Database (Denmark)

Werlauff, Erik

2009-01-01

The article analyses the legal consequences of the choice now available to Danish public limited companies, which can now opt for a two-tier management structure, in which the management board undertakes both the day-to-day and the overall management, while a supervisory board exercises control...... over the management board, including its appointment and dismissal. The article considers which companies a two-tier structure may be relevant for, and reviews the consequences for the composition, election and functioning of the company organs....

Alternate transmission with half-duplex relaying in MIMO interference relay networks

KAUST Repository

Park, Seongho; Ko, Youngchai; Park, Kihong; Alouini, Mohamed-Slim

2013-01-01

In this paper, we consider an alternate transmission scheme for a multiple-input multiple-output interference relay channel where multiple sources transmit their own signals to their corresponding destinations via one of two relaying groups

Opportunistic Relay Selection With Limited Feedback

KAUST Repository

Eltayeb, Mohammed E.; Elkhalil, Khalil; Bahrami, Hamid Reza; Al-Naffouri, Tareq Y.

2015-01-01

Relay selection is a simple technique that achieves spatial diversity in cooperative relay networks. Generally, relay selection algorithms require channel state information (CSI) feedback from all cooperating relays to make a selection decision

Supervisory control and diagnostics system for the mirror fusion test facility: overview and status 1980

International Nuclear Information System (INIS)

McGoldrick, P.R.

1981-01-01

The Mirror Fusion Test Facility (MFTF) is a complex facility requiring a highly-computerized Supervisory Control and Diagnostics System (SCDS) to monitor and provide control over ten subsystems; three of which require true process control. SCDS will provide physicists with a method of studying machine and plasma behavior by acquiring and processing up to four megabytes of plasma diagnostic information every five minutes. A high degree of availability and throughput is provided by a distributed computer system (nine 32-bit minicomputers on shared memory). Data, distributed across SCDS, is managed by a high-bandwidth Distributed Database Management System. The MFTF operators' control room consoles use color television monitors with touch sensitive screens; this is a totally new approach. The method of handling deviations to normal machine operation and how the operator should be notified and assisted in the resolution of problems has been studied and a system designed

CERN Relay Race

CERN Document Server

2008-01-01

The CERN relay race will take place around the Meyrin site on Thursday 5 June starting at 12:15 p.m. If possible, please avoid driving on the site during this 20-minute period. If you do meet runners while driving your car, please STOP until they have all passed. Thank you for your cooperation. Details on how to register your team for the relay race are given on the Staff Association Bulletin web site. You can access the online registration form at: http://cern.ch/club-running-relay/form.html

CERN Relay Race

CERN Document Server

2007-01-01

The CERN relay race will take place around the Meyrin site on Wednesday 23 May starting at 12:15. If possible, please avoid driving on the site during this 20-minute period. If you do meet runners while driving your car, please STOP until they have all passed. Thank you for your cooperation. Details on how to register your team for the relay race are given on the Staff Association Bulletin web site. You can access the online registration form at: http://cern.ch/club-running-relay/form.html

Power system relaying

CERN Document Server

Horowitz, Stanley H; Niemira, James K

2013-01-01

The previous three editions of Power System Relaying offer comprehensive and accessible coverage of the theory and fundamentals of relaying and have been widely adopted on university and industry courses worldwide. With the third edition, the authors have added new and detailed descriptions of power system phenomena such as stability, system-wide protection concepts and discussion of historic outages. Power System Relaying, 4th Edition continues its role as an outstanding textbook on power system protection for senior and graduate students in the field of electric power engineering and a refer

Self-Disclosure as a Predictor of EAP Supervisory Utilization

Science.gov (United States)

Donohoe, Timothy L.; Johnson, James T.; Taquino, Maurice A.

1999-01-01

The value of Employee Assistance Programs (EAPS) has been cited in a variety of published papers and articles. An important managerial element relative to the assessment and referral of troubled employees has been supervisory training. There has been numerous studies highlighting the various factors and circumstances associated with supervisory behavior and EAP referrals. The inclusion of emotional awareness factors in EAP supervisory utilization has not been thoroughly investigated, although frequently found in the literature as a training and development objective for managers in business and education. The present study sought to determine what role supervisory denial and anxiety avoidance plays in confrontation of troubled employees and if admission of specific, internal emotional events is a characteristic among EAP utilizing supervisors.

Proposal for the award of a contract for the supply of a supervisory control and data acquisition system for the four LHC experiments

CERN Document Server

2000-01-01

This document concerns the award of a contract for the supply of a Supervisory Control and Data Acquisition (SCADA) system for the control of the four LHC experiments. Following a market survey carried out among 63 firms in thirteen Member States and one firm in Israel, a call for tenders (IT-2814/IT) was sent on 29 May 2000 to two firms and two consortia, each consisting of two firms, in four Member States. By the closing date, CERN had received four tenders from three firms and one consortium in three Member States. The Finance Committee is invited to agree to the negotiation of a contract with ETM (AT), the lowest bidder complying with the specification, for the supply of a Supervisory Control and Data Acquisition (SCADA) system for the control of the four LHC experiments, including consultancy services and training, for a total amount of 407 500 euros (634 000 Swiss francs), not subject to revision, and 10 years? maintenance for a total amount of 308 500 euros (480 000 Swiss francs), subject to annual rev...

Development of a First-of-a-Kind Deterministic Decision-Making Tool for Supervisory Control System

Energy Technology Data Exchange (ETDEWEB)

Cetiner, Sacit M [ORNL; Kisner, Roger A [ORNL; Muhlheim, Michael David [ORNL; Fugate, David L [ORNL

2015-07-01

Decision-making is the process of identifying and choosing alternatives where each alternative offers a different approach or path to move from a given state or condition to a desired state or condition. The generation of consistent decisions requires that a structured, coherent process be defined, immediately leading to a decision-making framework. The overall objective of the generalized framework is for it to be adopted into an autonomous decision-making framework and tailored to specific requirements for various applications. In this context, automation is the use of computing resources to make decisions and implement a structured decision-making process with limited or no human intervention. The overriding goal of automation is to replace or supplement human decision makers with reconfigurable decision- making modules that can perform a given set of tasks reliably. Risk-informed decision making requires a probabilistic assessment of the likelihood of success given the status of the plant/systems and component health, and a deterministic assessment between plant operating parameters and reactor protection parameters to prevent unnecessary trips and challenges to plant safety systems. The implementation of the probabilistic portion of the decision-making engine of the proposed supervisory control system was detailed in previous milestone reports. Once the control options are identified and ranked based on the likelihood of success, the supervisory control system transmits the options to the deterministic portion of the platform. The deterministic multi-attribute decision-making framework uses variable sensor data (e.g., outlet temperature) and calculates where it is within the challenge state, its trajectory, and margin within the controllable domain using utility functions to evaluate current and projected plant state space for different control decisions. Metrics to be evaluated include stability, cost, time to complete (action), power level, etc. The

MIMO Four-Way Relaying

DEFF Research Database (Denmark)

Liu, Huaping; Sun, Fan; De Carvalho, Elisabeth

2013-01-01

Two-way relaying in wireless systems has initiated a large research effort during the past few years. Nevertheless, it represents only a specific traffic pattern and it is of interest to investigate other traffic patterns where such a simultaneous processing of information flows can bring...... performance advantage. In this paper we consider a \\emph{four-way relaying} multiple-input multiple-output (MIMO) scenario, where each of the two Mobile Stations (MSs) has a two-way connection to the same Base Station (BS), while each connection is through a dedicated Relay Station (RS). The RSs are placed...... the sum-rate of the new scheme for Decode-and-Forward (DF) operational model for the RS. We compare the performance with state-of-the-art reference schemes, based on two-way relaying with DF. The results indicate that the sum-rate of the two-phase four-way relaying scheme largely outperforms the four...

An automated thermoelectric power apparatus using electro-optic relays

International Nuclear Information System (INIS)

Chakravarti, A.; Ranganathan, R.

1992-01-01

We report the design and construction of a thermoelectric power apparatus using home-made electro-optic relays with Z-80A microprocessor for automatic data acquisition and control. The advantages of such relays made out of LED-LDR combinations for the measurement of ΔE and ΔT are discussed in details. (author). 7 refs., 5 figs

49 CFR 236.206 - Battery or power supply with respect to relay; location.

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Battery or power supply with respect to relay..., AND APPLIANCES Automatic Block Signal Systems Standards § 236.206 Battery or power supply with respect to relay; location. The battery or power supply for each signal control relay circuit, where an open...

Performance analysis of two-way amplify and forward relaying with adaptive modulation over multiple relay network

KAUST Repository

Hwang, Kyusung; Ko, Youngchai; Alouini, Mohamed-Slim

2011-01-01

In this letter, we propose two-way amplify-and-forward relaying in conjunction with adaptive modulation in order to improve spectral efficiency of relayed communication systems while monitoring the required error performance. We also consider a multiple relay network where only the best relay node is utilized so that the diversity order increases while maintaining a low complexity of implementation as the number of relays increases. Based on the best relay selection criterion, we offer an upper bound on the signal-to-noise ratio to keep the performance analysis tractable. Our numerical examples show that the proposed system offers a considerable gain in spectral efficiency while satisfying the error rate requirements. © 2011 IEEE.

Performance analysis of two-way amplify and forward relaying with adaptive modulation over multiple relay network

KAUST Repository

Hwang, Kyusung

2011-02-01

In this letter, we propose two-way amplify-and-forward relaying in conjunction with adaptive modulation in order to improve spectral efficiency of relayed communication systems while monitoring the required error performance. We also consider a multiple relay network where only the best relay node is utilized so that the diversity order increases while maintaining a low complexity of implementation as the number of relays increases. Based on the best relay selection criterion, we offer an upper bound on the signal-to-noise ratio to keep the performance analysis tractable. Our numerical examples show that the proposed system offers a considerable gain in spectral efficiency while satisfying the error rate requirements. © 2011 IEEE.

Opportunistic Relay Selection With Limited Feedback

KAUST Repository

Eltayeb, Mohammed E.

2015-08-01

Relay selection is a simple technique that achieves spatial diversity in cooperative relay networks. Generally, relay selection algorithms require channel state information (CSI) feedback from all cooperating relays to make a selection decision. This requirement poses two important challenges, which are often neglected in the literature. Firstly, the fed back channel information is usually corrupted by additive noise. Secondly, CSI feedback generates a great deal of feedback overhead (air-time) that could result in significant performance hits. In this paper, we propose a compressive sensing (CS) based relay selection algorithm that reduces the feedback overhead of relay networks under the assumption of noisy feedback channels. The proposed algorithm exploits CS to first obtain the identity of a set of relays with favorable channel conditions. Following that, the CSI of the identified relays is estimated using least squares estimation without any additional feedback. Both single and multiple relay selection cases are considered. After deriving closed-form expressions for the asymptotic end-to-end SNR at the destination and the feedback load for different relaying protocols, we show that CS-based selection drastically reduces the feedback load and achieves a rate close to that obtained by selection algorithms with dedicated error-free feedback. © 1972-2012 IEEE.

Development of new supervisory system with ITV. ITV ni yoru kanshi system ni kansuru kenkyu

Energy Technology Data Exchange (ETDEWEB)

Shimonaga, S; Matsunaga, R; Ono, H [The Kyushu Electric Power Co. Inc., Fukuoka (Japan)

1994-02-28

This paper describes an automatic trespassing supervisory system with ITV and picture processing (PP). The paper details an integrated control system and automatic supervision. The system functions to automatically detect a trespassing by means of PP, transfers items of information collected by sensors to a remote control center, and records relevant data. The operation principle consists of measurement of change in two or more images of moving bodies with binary value at a certain interval, determination on acceptability of the moving bodies represented by human characteristics, and identification of a trespasser. The system consists of an automatic supervisory device using PP and an automatic patrolling and searching device by means of sensor measurements. The supervisory device has images outputted from ITV and VTR processed by PP, host computer, and HD, and linked to an indication mechanism. According to the result of a site test at wireless transmission station of Kyushu Electric Power Company, the difference between measurement values collected by the searching device and those by the supervisory device was [plus minus]3% or less (other than EG output current), which is a useful value for verification. Although the basic technique has been established, practical use of the system still has some problems including performance improvement in picture processing. 37 refs., 38 figs., 18 tabs.

Ready, steady… relay!

CERN Multimedia

2008-01-01

Thursday 5 June. With another year comes another success for CERN’s Relay Race. With 76 teams taking part it was the second highest turnout in the race’s history. ‘The Shabbys’ won the relay race in 10 minutes 51 seconds.As popular as ever, this year the relay race took on the atmosphere of a mini carnival. Gathering on the lawn outside Restaurant 1, various stalls and attractions added to the party feeling of the event, with beer courtesy of ‘AGLUP’, the Belgian beer club, and a wandering jazz group entertaining spectators and competitors alike. Reflecting the greater involvement of other associations in the relay race, the president of the Staff Association Clubs Committee, James Purvis, was the guest of honour, launching the start of the race and presenting the prizes. As regular followers of the race could have probably predicted, The Shabbys were once again victorious and claimed first place. The team members th...

Whether and Where to Code in the Wireless Relay Channel

DEFF Research Database (Denmark)

Shi, Xiaomeng; Médard, Muriel; Roetter, Daniel Enrique Lucani

2013-01-01

The throughput benefits of random linear network codes have been studied extensively for wirelined and wireless erasure networks. It is often assumed that all nodes within a network perform coding operations. In energy-constrained systems, however, coding subgraphs should be chosen to control...... the number of coding nodes while maintaining throughput. In this paper, we explore the strategic use of network coding in the wireless packet erasure relay channel according to both throughput and energy metrics. In the relay channel, a single source communicates to a single sink through the aid of a half......-duplex relay. The fluid flow model is used to describe the case where both the source and the relay are coding, and Markov chain models are proposed to describe packet evolution if only the source or only the relay is coding. In addition to transmission energy, we take into account coding and reception...

A genetic algorithm for multiple relay selection in two-way relaying cognitive radio networks

KAUST Repository

Alsharoa, Ahmad M.

2013-09-01

In this paper, we investigate a multiple relay selection scheme for two-way relaying cognitive radio networks where primary users and secondary users operate on the same frequency band. More specifically, cooperative relays using Amplifyand- Forward (AF) protocol are optimally selected to maximize the sum rate of the secondary users without degrading the Quality of Service (QoS) of the primary users by respecting a tolerated interference threshold. A strong optimization tool based on genetic algorithm is employed to solve our formulated optimization problem where discrete relay power levels are considered. Our simulation results show that the practical heuristic approach achieves almost the same performance of the optimal multiple relay selection scheme either with discrete or continuous power distributions. Copyright © 2013 by the Institute of Electrical and Electronic Engineers, Inc.

Report on the experience with the Supervisory Control and Diagnostics System (SCDS) of MFTF-B

International Nuclear Information System (INIS)

Wyman, R.H.

1983-01-01

The Supervisory Control and Diagnostics System (SCDS) of MFTF is a multiprocessor computer system using graphics oriented displays with touch sensitive panels as the primary operator interface. Late in the calendar year 1981 the system was used to control an integrated test of the vacuum vessel, vacuum system, cryogenics system and the superconducting magnet of MFTF. Since the completion of those tests and starting in early calendar 1983 the system has been used for control of the neutral beam test facility at LLNL. This paper presents a short overview of SCDS for the purpose of orientation and then proceeds to describe the difficulties encountered in these preliminary encounters with reality. The band-aids used to hold things together as disaster threatened as well as the long-term solutions to the problems will be discussed. Finally, we will present some comments on system costs and management philosophy

Relay Selection with Limited and Noisy Feedback

KAUST Repository

Eltayeb, Mohammed E.

2016-01-28

Relay selection is a simple technique that achieves spatial diversity in cooperative relay networks. Nonetheless, relay selection algorithms generally require error-free channel state information (CSI) from all cooperating relays. Practically, CSI acquisition generates a great deal of feedback overhead that could result in significant transmission delays. In addition to this, the fed back channel information is usually corrupted by additive noise. This could lead to transmission outages if the central node selects the set of cooperating relays based on inaccurate feedback information. In this paper, we propose a relay selection algorithm that tackles the above challenges. Instead of allocating each relay a dedicated channel for feedback, all relays share a pool of feedback channels. Following that, each relay feeds back its identity only if its effective channel (source-relay-destination) exceeds a threshold. After deriving closed-form expressions for the feedback load and the achievable rate, we show that the proposed algorithm drastically reduces the feedback overhead and achieves a rate close to that obtained by selection algorithms with dedicated error-free feedback from all relays. © 2015 IEEE.

Screening test of relays used under pressurized sulfur hexafluoride (SF6)

International Nuclear Information System (INIS)

Kutsukake, Kenichi; Matsuda, Makoto; Hanashima, Susumu; Obara, Kenjiro

2008-01-01

Many measurement and control devices inside of a high voltage terminal of the JAEA-Tokai tandem accelerator are operated under pressurized sulfur hexafluoride gas (SF 6 ) of 0.5 MPa. This screening test has been carried out to select a relay, which is usable under the pressurized SF 6 for turn on and off a large current of the devices, from commercial relays used in the atmospheric condition. Four kinds of relays were tested: electromechanical relay (EMR), magnet contactor (MAG), solid-state relay (SSR) and hybrid relay (HYB). Temperature and appearance changes of the relay were collected as measurement items. In addition, a reason of contact trouble of the relays was considered from the results of qualitative elementary analysis and observation of the contact surface using the EDS (energy-dispersive X-ray spectroscopy) and the SEM (scanning electron microscope). As a result, the EMR and the MAG showed irregular contact in spite of input voltage and electric current had fed to an operational coil of the relay normally. It is caused by the sulfide or fluoride compounds, which were formed by chemical reaction between metals and sulfur or hydrogen fluoride due to dissociation of SF 6 in electric arcs. On the other hand, the performance of the SSR and the HYB is better than the EMR and the MAG, and it was found that these relays are available in the pressurized SF 6 of 0.5MPa in spite of the standard specification. (author)

Securing Relay Networks with Artificial Noise: An Error Performance-Based Approach

Directory of Open Access Journals (Sweden)

Ying Liu

2017-07-01

Full Text Available We apply the concept of artificial and controlled interference in a two-hop relay network with an untrusted relay, aiming at enhancing the wireless communication secrecy between the source and the destination node. In order to shield the square quadrature amplitude-modulated (QAM signals transmitted from the source node to the relay, the destination node designs and transmits artificial noise (AN symbols to jam the relay reception. The objective of our considered AN design is to degrade the error probability performance at the untrusted relay, for different types of channel state information (CSI at the destination. By considering perfect knowledge of the instantaneous CSI of the source-to-relay and relay-to-destination links, we first present an analytical expression for the symbol error rate (SER performance at the relay. Based on the assumption of an average power constraint at the destination node, we then derive the optimal phase and power distribution of the AN that maximizes the SER at the relay. Furthermore, we obtain the optimal AN design for the case where only statistical CSI is available at the destination node. For both cases, our study reveals that the Gaussian distribution is generally not optimal to generate AN symbols. The presented AN design takes into account practical parameters for the communication links, such as QAM signaling and maximum likelihood decoding.

Leadership Development: A Supervisory Responsibility

National Research Council Canada - National Science Library

French, David

2000-01-01

.... This is a recurring theme found throughout leadership literature and speeches. The US Air Force clearly establishes subordinate development as a supervisory responsibility in top-level doctrine...

12 CFR 261.20 - Confidential supervisory information made available to supervised financial institutions and...

Science.gov (United States)

2010-01-01

... available to supervised financial institutions and financial institution supervisory agencies. 261.20... Supervised Institutions, Financial Institution Supervisory Agencies, Law Enforcement Agencies, and Others in... institutions and financial institution supervisory agencies. (a) Disclosure of confidential supervisory...

Nonconformance in electromechanical output relays of microprocessor-based protection devices under actual operating conditions

OpenAIRE

Gurevich, Vladimir

2006-01-01

Microprocessor-based protection relays are gradually driving out traditional electromechanical and even electronic protection devices from virtually all fields of power and electrical engineering. In this paper, one of many problems of microprocessor-based relays is discussed: nonconformance of miniature electromechanical output relays under actual operation conditions: switching inductive loads (with tripping CB coils or lockout relay coils) at 220 VDC, and "dry" switching of some control ci...

Review of first line supervisory positions in nuclear power plants - Phase II

Energy Technology Data Exchange (ETDEWEB)

Mackenzie, C W; Huntley, M [Hickling Corp., Ottawa, ON (Canada)

1995-10-01

This report provides an overview of first line supervisory activities at Ontario Hydro nuclear generating stations (Pickering `A` and Bruce `B`) and the Point Lepreau nuclear generating station in New Brunswick. Activity profiles describing the range of first line supervisory roles and responsibilities for nuclear operators have been developed from survey data and flowcharting methods. These activity profiles have then been compared with formal job responsibilities as identified in job descriptions, supervisory training provided and assessment criteria used to evaluate supervisors. Finally, this report relates the findings of supervisory practices in the group under study with the findings in the current literature relating to supervisory functioning. (author). 32 tabs., 2 figs.

Review of first line supervisory positions in nuclear power plants - Phase II

International Nuclear Information System (INIS)

Mackenzie, C.W.; Huntley, M.

1995-10-01

This report provides an overview of first line supervisory activities at Ontario Hydro nuclear generating stations (Pickering 'A' and Bruce 'B') and the Point Lepreau nuclear generating station in New Brunswick. Activity profiles describing the range of first line supervisory roles and responsibilities for nuclear operators have been developed from survey data and flowcharting methods. These activity profiles have then been compared with formal job responsibilities as identified in job descriptions, supervisory training provided and assessment criteria used to evaluate supervisors. Finally, this report relates the findings of supervisory practices in the group under study with the findings in the current literature relating to supervisory functioning. (author). 32 tabs., 2 figs

Development of Supervisory Control and Data Acquisition (SCADA) Electrical Supply in Malaysian Nuclear Agency

International Nuclear Information System (INIS)

Zainudin Jaafar; Mohd Ashhar Khalid; Mohd Hanafiah Chik

2015-01-01

Nuclear Power supplies in Malaysia supplied from the power utility company Tenaga Nasional Berhad through several substations before reaching the building and equipment. The power supply is received and passed down through the 11000 V high voltage switch gears to 415 V 3-phase or 1-phase 240 V. The equipment used in this process is dangerous and monitoring hardware operating remotely (remote) is the best as only guard machinery may engage in business operations. Similarly, the supply of electrical parameters should be monitored to ensure safe and continuous supply of and according to the appropriate voltage for record and analysis when needed. This paper discusses the monitoring and data acquisition is performed using the system 'Supervisory Control And Data Acquisition (SCADA) was developed. (author)

Distributed Supervisory Protection Interlock System

International Nuclear Information System (INIS)

Walz, H.V.; Agostini, R.C.; Barker, L.; Cherkassky, R.; Constant, T.; Matheson, R.

1989-03-01

The Distributed Supervisory Protection Interlock System, DSPI, is under development at the Stanford Linear Accelerator Center for requirements in the areas of personnel protection, beam containment and equipment protection interlocks. The DSPI system, distributed over the application site, consists of segments with microprocessor-based controller and I/O modules, local area networks for communication, and a global supervisor computer. Segments are implemented with commercially available controller and I/O modules arranged in local interlock clusters, and associated software. Segments provide local interlock data acquisition, processing and control. Local area networks provide the communication backbone between segments and a global supervisor processor. The supervisor processor monitors the overall system, reports detail status and provides human interfaces. Details of an R and D test system, which will implement the requirements for personnel protection of 4 typical linear accelerator sectors, will be described. 4 refs., 2 figs

Optimal relay selection and power allocation for cognitive two-way relaying networks

KAUST Repository

Pandarakkottilil, Ubaidulla; Aï ssa, Sonia

2012-01-01

In this paper, we present an optimal scheme for power allocation and relay selection in a cognitive radio network where a pair of cognitive (or secondary) transceiver nodes communicate with each other assisted by a set of cognitive two-way relays

Buffer-Aided Relaying with Adaptive Link Selection

DEFF Research Database (Denmark)

Zlatanov, Nikola; Schober, Robert; Popovski, Petar

2013-01-01

In this paper, we consider a simple network consisting of a source, a half-duplex decode-and-forward relay, and a destination. We propose a new relaying protocol employing adaptive link selection, i.e., in any given time slot, based on the channel state information of the source-relay and the relay......-destination link a decision is made whether the source or the relay transmits. In order to avoid data loss at the relay, adaptive link selection requires the relay to be equipped with a buffer such that data can be queued until the relay-destination link is selected for transmission. We study both delay......-constrained and delay-unconstrained transmission. For the delay-unconstrained case, we characterize the optimal link selection policy, derive the corresponding throughput, and develop an optimal power allocation scheme. For the delay-constrained case, we propose to starve the buffer of the relay by choosing...

Relay Selection with Limited and Noisy Feedback

KAUST Repository

Eltayeb, Mohammed E.; Elkhalil, Khalil; Mas'ud, Abdullahi Abubakar; Al-Naffouri, Tareq Y.

2016-01-01

Relay selection is a simple technique that achieves spatial diversity in cooperative relay networks. Nonetheless, relay selection algorithms generally require error-free channel state information (CSI) from all cooperating relays. Practically, CSI

CERN Relay Race

CERN Multimedia

2009-01-01

The CERN relay race, now in its 39th year, is already a well-known tradition, but this year the organizers say the event will have even more of a festival feeling. Just off the starting line of the CERN relay race.For the past few years, spectators and runners at the CERN relay race have been able to enjoy a beer while listening to music from the CERN music and jazz clubs. But this year the organizers are aiming for "even more of a festival atmosphere". As David Nisbet, President of the CERN running club and organizer of the relay race, says: "Work is not just about getting your head down and doing the theory, it’s also about enjoying the company of your colleagues." This year, on top of music from the Santa Luis Band and the Canettes Blues Band, there will be demonstrations from the Aikido and softball clubs, a stretching session by the Fitness club, as well as various stalls and of course, the well-earned beer from AGLUP, the B...

Physical Layer Security Using Two-Path Successive Relaying

Directory of Open Access Journals (Sweden)

Qian Yu Liau

2016-06-01

Full Text Available Relaying is one of the useful techniques to enhance wireless physical-layer security. Existing literature shows that employing full-duplex relay instead of conventional half-duplex relay improves secrecy capacity and secrecy outage probability, but this is at the price of sophisticated implementation. As an alternative, two-path successive relaying has been proposed to emulate operation of full-duplex relay by scheduling a pair of half-duplex relays to assist the source transmission alternately. However, the performance of two-path successive relaying in secrecy communication remains unexplored. This paper proposes a secrecy two-path successive relaying protocol for a scenario with one source, one destination and two half-duplex relays. The relays operate alternately in a time division mode to forward messages continuously from source to destination in the presence of an eavesdropper. Analytical results reveal that the use of two half-duplex relays in the proposed scheme contributes towards a quadratically lower probability of interception compared to full-duplex relaying. Numerical simulations show that the proposed protocol achieves the ergodic achievable secrecy rate of full-duplex relaying while delivering the lowest probability of interception and secrecy outage probability compared to the existing half duplex relaying, full duplex relaying and full duplex jamming schemes.

Handover Framework for Relay Enhanced LTE Networks

DEFF Research Database (Denmark)

Teyeb, Oumer Mohammed; Van Phan, Vinh; Raaf, Bernhard

2009-01-01

Relaying is one of the proposed technologies for future releases of UTRAN Long Term Evolution (LTE) networks. Introducing relaying is expected to increase the coverage and capacity of LTE networks. In order to enable relaying, the architecture, protocol and radio resource management procedures...... of LTE, such as handover, have to be modified. A user can be handed over not only between two base stations, but also between relays and base stations, and between two relays. With the introduction of relaying, there is a need for a new procedure to hand over a relay and all its associated users...... to another base station, allowing a flexible and dynamic relay deployment. In this paper, we extend the LTE release 8 handover mechanisms so that it can accommodate these new handover functionalities in a flexible manner....

Optimal relay selection and power allocation for cognitive two-way relaying networks

KAUST Repository

Pandarakkottilil, Ubaidulla

2012-06-01

In this paper, we present an optimal scheme for power allocation and relay selection in a cognitive radio network where a pair of cognitive (or secondary) transceiver nodes communicate with each other assisted by a set of cognitive two-way relays. The secondary nodes share the spectrum with a licensed primary user (PU), and each node is assumed to be equipped with a single transmit/receive antenna. The interference to the PU resulting from the transmission from the cognitive nodes is kept below a specified limit. We propose joint relay selection and optimal power allocation among the secondary user (SU) nodes achieving maximum throughput under transmit power and PU interference constraints. A closed-form solution for optimal allocation of transmit power among the SU transceivers and the SU relay is presented. Furthermore, numerical simulations and comparisons are presented to illustrate the performance of the proposed scheme. © 2012 IEEE.

Relay Architectures for 3GPP LTE-Advanced

Directory of Open Access Journals (Sweden)

Peters StevenW

2009-01-01

Full Text Available The Third Generation Partnership Project's Long Term Evolution-Advanced is considering relaying for cost-effective throughput enhancement and coverage extension. While analog repeaters have been used to enhance coverage in commercial cellular networks, the use of more sophisticated fixed relays is relatively new. The main challenge faced by relay deployments in cellular systems is overcoming the extra interference added by the presence of relays. Most prior work on relaying does not consider interference, however. This paper analyzes the performance of several emerging half-duplex relay strategies in interference-limited cellular systems: one-way, two-way, and shared relays. The performance of each strategy as a function of location, sectoring, and frequency reuse are compared with localized base station coordination. One-way relaying is shown to provide modest gains over single-hop cellular networks in some regimes. Shared relaying is shown to approach the gains of local base station coordination at reduced complexity, while two-way relaying further reduces complexity but only works well when the relay is close to the handset. Frequency reuse of one, where each sector uses the same spectrum, is shown to have the highest network throughput. Simulations with realistic channel models provide performance comparisons that reveal the importance of interference mitigation in multihop cellular networks.

Commissioning of Temelin NPP as seen by scientific supervisory group

International Nuclear Information System (INIS)

Svoboda, C.

2003-01-01

Scientific Supervisory Group worked during the Temelin NPP commissioning process as an independent supervisor. The main tasks and main results of its activity are described in this contribution. The characteristic common features of commissioning process and most important events from the Scientific Supervisory Group point of view are presented. In April 1999 the Czech Power Utility with the objective to achieve maximum level of nuclear safety and quality within the NPP Temelin commissioning procedures has established a special body / Scientific Supervisory Group and requested Nuclear Research Institute Rez plc to perform the required function. The Scientific Supervisory Group proceeds in accordance with its Statute and provides an independent specialised professional and expert work focused on nuclear safety assurance, assesment of the selected documentation related to plant preparedness for the individual commissioning stages, and, of course. on assessment of the commissioning tests results. While performing its function the Scientific Supervisory Group is guided by the Atomic Act and the relevant Directives of State Office for Nuclear Safety; its activities are in compliance with the applicable IAEA recommendations (Authors)

PENINGKATAN KEAMANAN SUPERVISORY CONTROL AND DATA ACQUISITION (SCADA PADA SMART GRID SEBAGAI INFRASTRUKTUR KRITIS

Directory of Open Access Journals (Sweden)

Ahmad Budi Setiawan

2016-10-01

Full Text Available SCADA (Supervisory Control and Data Acquisition systems as the control unit of the smart grid has been used in almost various industries around the world in terms of automation systems. Smart grid technology combines the energy infrastructure and telecommunications and Internet networks. The system provides the operational ease and efficiency in the industry. However, the system has a lot of vulnerabilities in information security aspects that can have a major impact for the industry and even the economy. This study tried to design in building a smart grid cyber security, it includes the strategies that must be done and the information security system architecture to be built. The study was conducted qualitative in-depth interviews, focus group discussions and direct observation. Results of this research is the design strategy recommendations ddalam development of smart grid cyber security. Recommendation results of this study also intended as a suggestion-making framework for smart grid cyber security as a reference implementation of the smart grid in Indonesia.

The Supervisory Process of EFL Teachers: A Case Study

Science.gov (United States)

Chen, Cheryl Wei-Yu; Cheng, Yuh-show

2013-01-01

Supervision is an essential part of language teachers' professional experiences. The literature on language teacher supervision from the past few decades consists largely of descriptions of supervisory approaches (Bailey, 2009) and analysis of the supervisory discourse (Hooton, 2008; Wajnryb, 1994; 1995; 1998; Wallace & Woolger, 1991). This…

Full-Duplex Relay Selection in Cognitive Underlay Networks

KAUST Repository

Khafagy, Mohammad Galal; Alouini, Mohamed-Slim; Aissa, Sonia

2017-01-01

In this work, we analyze the performance of full-duplex relay selection (FDRS) in spectrum-sharing networks. Contrary to half-duplex relaying, full-duplex relaying (FDR) enables simultaneous listening/forwarding at the secondary relay(s), thereby

Conventional and intelligent generalized supervisory control for combined cycle generating power stations.; Control supervisiorio generalizado convencional e inteligente para centrales de generacion de ciclo combinado

Energy Technology Data Exchange (ETDEWEB)

Martinez M, Miguel A; Sanchez P, Marino [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico); Gonzalez Rubio S, Jose L [Cento Nacional de Investigacion y Desarrollo Tecnologico (Cenidet), Cuernavaca, Morelos (Mexico)

2005-07-01

Under the expectations of expansion of electric power generation in Mexico, this work exposes the development of a conventional and intelligent generalized supervisory control (CSG) for a combined cycle generation power plant. This one allows to obtain the optimal operation of the power plant through the automatic starting of the generating units and to obtain the maximum possible amount of electrical power in automatic and safe form. For the development of the CSG a control loop by temperature was implemented for the gas turbine system and a control loop by strangled pressure for the gas turbine and a control loop by strangled pressure for the steam turbine. The design of these supervisory systems was made with base in the critical limits on the involved variables of the process: blading average temperature, for the gas turbine (GT) and strangled pressure for the steam turbine (ST) [Spanish] Bajo estas expectativas de expansion de generacion de energia en Mexico, este trabajo expone el desarrollo de un control supervisorio generalizado (CSG) para una central generacion de ciclo combinado. Este permite lograr la operacion optima de la planta a traves del arranque automatico de las unidades generadoras y obtener la maxima cantidad posible de potencia electrica en forma automatica y segura. Para el desarrollo del CSG se implanto un lazo de control por temperatura para el sistema de turbina de gas y un lazo de control por presion estrangulada para la turbina de gas y un lazo de control por presion estrangulada para la turbina de vapor. El diseno de estos sistemas supervisorio se realizo con base en los limites criticos de las variables del proceso involucradas: temperatura promedio de empaletado para la turbina de gas (TG) y presion estrangulada para la turbina de vapor (TV)

Capacity gains of buffer-aided moving relays

KAUST Repository

Zafar, Ammar

2017-03-14

This work investigates the gain due to reduction in path loss by deploying buffer-aided moving relaying. In particular, the increase in gain due to moving relays is studied for dual-hop broadcast channels and the bidirectional relay channel. It is shown that the exploited gains in these channels due to buffer-aided relaying can be enhanced by utilizing the fact that a moving relay can communicate with the terminal closest to it and store the data in the buffer and then forward the data to the intended destination when it comes in close proximity with the destination. Numerical results show that for both the considered channels the achievable rates are increased as compared to the case of stationary relays. Numerical results also show that more significant increase in performance is seen when the relay moves to-and-fro between the source and the relay.

Capacity gains of buffer-aided moving relays

KAUST Repository

Zafar, Ammar; Shaqfeh, Mohammad; Alnuweiri, Hussein; Alouini, Mohamed-Slim

2017-01-01

This work investigates the gain due to reduction in path loss by deploying buffer-aided moving relaying. In particular, the increase in gain due to moving relays is studied for dual-hop broadcast channels and the bidirectional relay channel. It is shown that the exploited gains in these channels due to buffer-aided relaying can be enhanced by utilizing the fact that a moving relay can communicate with the terminal closest to it and store the data in the buffer and then forward the data to the intended destination when it comes in close proximity with the destination. Numerical results show that for both the considered channels the achievable rates are increased as compared to the case of stationary relays. Numerical results also show that more significant increase in performance is seen when the relay moves to-and-fro between the source and the relay.

Design on human supervisory control of safety management for advance NPP

International Nuclear Information System (INIS)

Nugroho, D.H.; Soentono, S.; Taryo, T.; Wahyon, P.I.

2006-01-01

Full text: Full text: Characteristics of an advance NPP related with economic and safety enhancement was represented on capabilities in intelligent control and diagnostic to provide nearly autonomous operation with anticipatory maintenance. An autonomous control system should enable automatic operation while adapting to component faults and system variable upsets. It needs therefore to have many intelligent capabilities, such as modeling, analysis, self-validation, diagnosis and decision. This paper describes a human supervisory control design for nuclear reactor fault management which collaborates between human and autonomous control. The beneficial of collaboration is provided based on belief of information value evaluated from Dempster's rule of evidence. The belief of the collaboration is better compared with single usage. The collaboration was conducted in which agent will autonomously and periodically be conducting surveillance by checking the component abnormalities in the plant if anomalies occur. The anomalies were determined using fault detection module. Thereby the system will be able to conduct preventive maintenance. In the situation of accident happened, hence the system will diagnose to determine the location of component failure autonomously. A human supervisor will then determine the action of decison making based on the prediction result. The decision making will be conducted based on the 4th Sheridan's autonomous level in which the autonomous control will execute the duty autonomously when the plant is in normal condition, or in the predictable accident range. But if the unpredictable accident occurs in the plant, the supervisor will then take over the role to control the plant, and the machine will do what commanded by the supervisor. Sistematically, the system explained before was represented by Traveling Salesman Problem-based surveillance, modified ART-2 artificial neural networks-based fault detection and Bayesian Networks-based fault

Performance analysis of opportunistic nonregenerative relaying

KAUST Repository

Tourki, Kamel; Alouini, Mohamed-Slim; Qaraqe, Khalid A.; Yang, Hongchuan

2013-01-01

Opportunistic relaying in cooperative communication depends on careful relay selection. However, the traditional centralized method used for opportunistic amplify-and-forward protocols requires precise measurements of channel state information at the destination. In this paper, we adopt the max-min criterion as a relay selection framework for opportunistic amplify-and-forward cooperative communications, which was exhaustively used for the decode-and-forward protocol, and offer an accurate performance analysis based on exact statistics of the local signal-to-noise ratios of the best relay. Furthermore, we evaluate the asymptotical performance and deduce the diversity order of our proposed scheme. Finally, we validate our analysis by showing that performance simulation results coincide with our analytical results over Rayleigh fading channels, and we compare the max-min relay selection with their centralized channel state information-based and partial relay selection counterparts.

Perceptions of Administrative and Supervisory Support in Public Child Welfare

Directory of Open Access Journals (Sweden)

Tonya M. Westbrook

2012-06-01

Full Text Available Using the Child Welfare Organizational Culture Inventory (CWOCI in a public child welfare agency, perceptions of administrative and supervisory support held by employees with social work degrees (BSW and MSW were compared to perceptions of administrative and supervisory support held by employees without social work degrees. Child welfare employees with social work degrees reported lower administrative and supervisory support than employees without social work degrees. Implications for social work educators, public child welfare administrators and supervisors, and future research are presented.

Supervisory selection and development yields payback

International Nuclear Information System (INIS)

Rubino, E.A.

1991-01-01

The selection and development of first line supervisors is a critical factor in a strategic effort to bring about organizational change, to improve performance and productivity and to enhance professionalism in the work force. Candidates for first line supervisory positions at Philadelphia Electric Company are no longer promoted purely on the basis of seniority. A Supervisory Selection Assessment Center permits candidates to demonstrate leadership potential. Successful candidates then attend an eight week Supervisory Development Academy, away from the work place. On successful completion of the Academy, the supervisor assembles his or her work team and, with training and leadership, shapes a performance based work team ready to plan, execute and assess its own work. Since this radically different program was initiated in September, 1989, results have been highly acclaimed by management. Contractor support has been sharply reduced, budgets have been met and reduced more work has been accomplished and fewer overtime hours have been needed. Workers attend training with no loss of team productivity. Each SDA graduate and his team sets goals to improve quality, increase productivity, increase efficiency, maintain ALARA, improve safety and effect cultural change while improving job satisfaction and morale

Energy efficient circuit design using nanoelectromechanical relays

Science.gov (United States)

Venkatasubramanian, Ramakrishnan

Nano-electromechanical (NEM) relays are a promising class of emerging devices that offer zero off-state leakage and behave like an ideal switch. Recent advances in planar fabrication technology have demonstrated that microelectromechanical (MEMS) scale miniature relays could be manufactured reliably and could be used to build fully functional, complex integrated circuits. The zero leakage operation of relays has renewed the interest in relay based low power logic design. This dissertation explores circuit architectures using NEM relays and NEMS-CMOS heterogeneous integration. Novel circuit topologies for sequential logic, memory, and power management circuits have been proposed taking into consideration the NEM relay device properties and optimizing for energy efficiency and area. In nanoscale electromechanical devices, dispersion forces like Van der Waals' force (vdW) affect the pull-in stability of the relay devices significantly. Verilog-A electromechanical model of the suspended gate relay operating at 1V with a nominal air gap of 5 - 10nm has been developed taking into account all the electrical, mechanical and dispersion effects. This dissertation explores different relay based latch and flip-flop topologies. It has been shown that as few as 4 relay cells could be used to build flip-flops. An integrated voltage doubler based flip flop that improves the performance by 2X by overdriving Vgb has been proposed. Three NEM relay based parallel readout memory bitcell architectures have been proposed that have faster access time, and remove the reliability issues associated with previously reported serial readout architectures. A paradigm shift in design of power switches using NEM relays is proposed. An interesting property of the relay device is that the ON state resistance (Ron) of the NEM relay switch is constant and is insensitive to the gate slew rate. This coupled with infinite OFF state resistance (Roff ) offers significant area and power advantages over CMOS

78 FR 40407 - Structure and Practices of the Video Relay Service Program: Telecommunications Relay Services and...

Science.gov (United States)

2013-07-05

...] Structure and Practices of the Video Relay Service Program: Telecommunications Relay Services and Speech-to... telecommunications relay services (TRS) program continues to offer functional equivalence to all eligible users and..., identified by CG Docket Nos. 10-51 and 03-123, by any of the following methods: Electronic Filers: Comments...

The impact of SFCL and SMES integration on the distance relay

Energy Technology Data Exchange (ETDEWEB)

Yang, Jun, E-mail: JYang@whu.edu.cn [School of Electrical Engineering, Wuhan University, Wuhan 430072 (China); Zhang, Liling; Wang, Xinpu; Chen, Lei [School of Electrical Engineering, Wuhan University, Wuhan 430072 (China); Chen, Yanxia [Beijing Electric Power Research Institute, Beijing 100075 (China)

2016-11-15

Highlights: • The impact of SFCL and SMES integration on the circle distance relay is studied. • The detailed models of SFCL and SMES with distance delay are built in MATLAB. • The integration of SFCL and SMES does influence the operation of distance relay. • An improved distance relay to prevent mal-operation is proposed and verified. - Abstract: The superconducting fault current limiter (SFCL) is an ideal short-circuit fault current limiting device that can limit the fault current without any delay and control the voltage drop of the non-fault line. The superconducting magnetic energy storage (SMES) device can exchange the active and reactive power independently, so it is applied broadly to improve power system stability. With SFCL, the low voltage ride-through capability of SMES can be enhanced as well as its MW and MJ capacities. The distance relay is a key electrical apparatus that will trip circuit breakers to protect electrical devices from short circuit faults. Due to the application of SFCL and SMES integration, the voltage and current in power grid will change accordingly, and the operation characteristic of distance relay may be affected. In this paper, the impact of a bridge-type SFCL and SMES integration on the circle distance relay is studied. And simulation results show that the integration of SFCL and SMES does influence the measured impedance of distance relay, which can lead to mal-operation of the circle distance relay. Furthermore, an improved distance relay is proposed and verified.

The impact of SFCL and SMES integration on the distance relay

International Nuclear Information System (INIS)

Yang, Jun; Zhang, Liling; Wang, Xinpu; Chen, Lei; Chen, Yanxia

2016-01-01

Highlights: • The impact of SFCL and SMES integration on the circle distance relay is studied. • The detailed models of SFCL and SMES with distance delay are built in MATLAB. • The integration of SFCL and SMES does influence the operation of distance relay. • An improved distance relay to prevent mal-operation is proposed and verified. - Abstract: The superconducting fault current limiter (SFCL) is an ideal short-circuit fault current limiting device that can limit the fault current without any delay and control the voltage drop of the non-fault line. The superconducting magnetic energy storage (SMES) device can exchange the active and reactive power independently, so it is applied broadly to improve power system stability. With SFCL, the low voltage ride-through capability of SMES can be enhanced as well as its MW and MJ capacities. The distance relay is a key electrical apparatus that will trip circuit breakers to protect electrical devices from short circuit faults. Due to the application of SFCL and SMES integration, the voltage and current in power grid will change accordingly, and the operation characteristic of distance relay may be affected. In this paper, the impact of a bridge-type SFCL and SMES integration on the circle distance relay is studied. And simulation results show that the integration of SFCL and SMES does influence the measured impedance of distance relay, which can lead to mal-operation of the circle distance relay. Furthermore, an improved distance relay is proposed and verified.

Relay for the automation of the exposition process in X-ray control of material quality

International Nuclear Information System (INIS)

Vladimirov, L.V.; Ermakova, T.N.; Krongauz, A.N.; Kurozaev, V.P.; Khlebtsevich, V.Yu.; Chernobrovov, S.V.; Shul'gina, Z.I.

1977-01-01

Discussed are the theoretical and experimental conceptions which constitute the basis for elaboration of an electronic relay intended for automation of the exposure process during X-ray inspection of the material quality. The operating principle and circuitry of the relay are described

Relay test program

International Nuclear Information System (INIS)

Bandyopadhyay, K.K.; Kunkel, C.; Shteyngart, S.

1994-02-01

This report presents the results of a relay test program conducted by Brookhaven National Laboratory (BNL) under the sponsorship of the US Nuclear Regulatory Commission (NRC). The program is a continuation of an earlier test program the results of which were published in NUREG/CR-4867. The current program was carried out in two phases: electrical testing and vibration testing. The objective was primarily to focus on the electrical discontinuity or continuity of relays and circuit breaker tripping mechanisms subjected to electrical pulses and vibration loads. The electrical testing was conducted by KEMA-Powertest Company and the vibration testing was performed at Wyle Laboratories, Huntsville, Alabama. This report discusses the test procedures, presents the test data, includes an analysis of the data and provides recommendations regarding reliable relay testing

CERN Relay Race

CERN Document Server

2006-01-01

The CERN relay race will take place around the Meyrin site on Wednesday 17 May starting at 12:15. If possible, please avoid driving on the site during this 20-minute period. If you do meet runners while driving your car, please STOP until they have all passed. Details on how to register your team for the relay race are given on the Staff Association Bulletin web site.

Non-parametric Tuning of PID Controllers A Modified Relay-Feedback-Test Approach

CERN Document Server

Boiko, Igor

2013-01-01

The relay feedback test (RFT) has become a popular and efficient  tool used in process identification and automatic controller tuning. Non-parametric Tuning of PID Controllers couples new modifications of classical RFT with application-specific optimal tuning rules to form a non-parametric method of test-and-tuning. Test and tuning are coordinated through a set of common parameters so that a PID controller can obtain the desired gain or phase margins in a system exactly, even with unknown process dynamics. The concept of process-specific optimal tuning rules in the nonparametric setup, with corresponding tuning rules for flow, level pressure, and temperature control loops is presented in the text.   Common problems of tuning accuracy based on parametric and non-parametric approaches are addressed. In addition, the text treats the parametric approach to tuning based on the modified RFT approach and the exact model of oscillations in the system under test using the locus of a perturbedrelay system (LPRS) meth...

Energy-efficient relay selection and optimal power allocation for performance-constrained dual-hop variable-gain AF relaying

KAUST Repository

Zafar, Ammar

2013-12-01

This paper investigates the energy-efficiency enhancement of a variable-gain dual-hop amplify-and-forward (AF) relay network utilizing selective relaying. The objective is to minimize the total consumed power while keeping the end-to-end signal-to-noise-ratio (SNR) above a certain peak value and satisfying the peak power constraints at the source and relay nodes. To achieve this objective, an optimal relay selection and power allocation strategy is derived by solving the power minimization problem. Numerical results show that the derived optimal strategy enhances the energy-efficiency as compared to a benchmark scheme in which both the source and the selected relay transmit at peak power. © 2013 IEEE.

SWIPT in Multiuser MIMO Decode-and-Forward Relay Broadcasting Channel with Energy Harvesting Relays

KAUST Repository

Benkhelifa, Fatma

2017-02-09

In this paper, we consider a multiuser multiple- input multiple-output (MIMO) decode-and-forward (DF) relay broadcasting channel (BC) with single source, multiple energy harvesting relays and multiple destinations. Since the end-to-end sum rate maximization problem is intractable, we tackle a simplified problem where we maximize the sum of the harvested energy at the relays, we employ the block diagonalization (BD) procedure at the source, and we mitigate the interference between the relay- destination channels. The interference mitigation at the destinations is managed in two ways: either to fix the interference covariance matrices at the destination and update them at each iteration until convergence, or to cancel the interference using an algorithm similar to the BD method. We provide numerical results to show the relevance of our proposed solution.

Signal-Noise Ratio Control Subsystem of Digital Equipment for Transmission of "Strela" Relay Protection Commands

Directory of Open Access Journals (Sweden)

I. I. Zabenkov

2012-01-01

Full Text Available Continuous measurement function of relative noise and interference level in the information transmission channel is considered as an important one for controlling parameters of high-frequency signal. The present paper simulates an algorithm for measuring signal-noise ratio in the transmission channel of high-voltage lines which is used in the digital equipment for transmission of relay protection and emergency automation commands of "Strela" complex.

Relaying Strategies and Protocols for Efficient Wireless Networks

KAUST Repository

Zafar, Ammar

2014-10-01

Next generation wireless networks are expected to provide high data rate and satisfy the Quality-of-Service (QoS) constraints of the users. A significant component of achieving these goals is to increase the effi ciency of wireless networks by either optimizing current architectures or exploring new technologies which achieve that. The latter includes revisiting technologies which were previously proposed, but due to a multitude of reasons were ignored at that time. One such technology is relaying which was initially proposed in the latter half of the 1960s and then was revived in the early 2000s. In this dissertation, we study relaying in conjunction with resource allocation to increase the effi ciency of wireless networks. In this regard, we differentiate between conventional relaying and relaying with buffers. Conventional relaying is traditional relaying where the relay forwards the signal it received immediately. On the other hand, in relaying with buffers or buffer-aided relaying as it is called, the relay can store received data in its buffer and forward it later on. This gives the benefit of taking advantage of good channel conditions as the relay can only transmit when the channel conditions are good. The dissertation starts with conventional relaying and considers the problem of minimizing the total consumed power while maintaining system QoS. After upper bounding the system performance, more practical algorithms which require reduced feedback overhead are explored. Buffer-aided relaying is then considered and the joint user-and-hop scheduler is introduced which exploits multi-user diversity (MUD) and 5 multi-hop diversity (MHD) gains together in dual-hop broadcast channels. Next joint user-and-hop scheduling is extended to the shared relay channel where two source-destination pairs share a single relay. The benefits of buffer-aided relaying in the bidirectional relay channel utilizing network coding are then explored. Finally, a new transmission protocol

Spoiled Onions: Exposing Malicious Tor Exit Relays

OpenAIRE

Winter, Philipp; Lindskog, Stefan

2014-01-01

Several hundred Tor exit relays together push more than 1 GiB/s of network traffic. However, it is easy for exit relays to snoop and tamper with anonymised network traffic and as all relays are run by independent volunteers, not all of them are innocuous. In this paper, we seek to expose malicious exit relays and document their actions. First, we monitored the Tor network after developing a fast and modular exit relay scanner. We implemented several scanning modules for detecting common attac...

Vacuum control system of VEC

International Nuclear Information System (INIS)

Roy, Anindya; Bhole, R.B.; Bandopadhyay, D.L.; Mukhopadhyay, B.; Pal, Sarbajit; Sarkar, D.

2009-01-01

As a part of modernization of VEC (Variable Energy Cyclotron), the Vacuum Control System is being upgraded to PLC based automated system from initial Relay based Manual system. EPICS (Experimental Physics and Industrial Control System), a standard open source software tool for designing distributed control system, is chosen for developing the supervisory control software layer, leading towards a unified distributed control architecture of VEC Control System. A Modbus - TCP based IOC (I/O Controller) has been developed to communicate control data to PLC using Ethernet-TCP LAN. Keeping in mind, the operators' familiarity with MS-Windows, a MS-Windows based operator interface is developed using VB6. It is also used to test and evaluate EPICS compatibility to MS Windows. Several MS Windows ActiveX components e.g. text display, image display, alarm window, set-point input etc. have been developed incorporating Channel Access library of EPICS. Use of such components ease the programming complexity and reduce developmental time of the operator interface. The system is in the final phase of commissioning. (author)

32 CFR 776.53 - Responsibilities of the Judge Advocate General and supervisory attorneys.

Science.gov (United States)

2010-07-01

... of the Judge Advocate General and supervisory attorneys. (a) Responsibilities of the Judge Advocate General and supervisory attorneys. (1) The JAG and supervisory attorneys shall make reasonable efforts to... 32 National Defense 5 2010-07-01 2010-07-01 false Responsibilities of the Judge Advocate General...

SWIPT in Multiuser MIMO Decode-and-Forward Relay Broadcasting Channel with Energy Harvesting Relays

KAUST Repository

Benkhelifa, Fatma; Salem, Ahmed Sultan; Alouini, Mohamed-Slim

2017-01-01

In this paper, we consider a multiuser multiple- input multiple-output (MIMO) decode-and-forward (DF) relay broadcasting channel (BC) with single source, multiple energy harvesting relays and multiple destinations. Since the end-to-end sum rate

Relay model for recruiting alcohol dependent patients in general hospitals--a single-blind pragmatic randomized trial

DEFF Research Database (Denmark)

Schwarz, Anne-Sophie; Bilberg, Randi; Bjerregaard, Lene Berit Skov

2016-01-01

- The Relay Model. METHOD/DESIGN: The study is a single-blind pragmatic randomized controlled trial including patients admitted to the hospital. The study group (n = 500) will receive an intervention, and the control group (n = 500) will be referred to treatment by usual procedures. All patients complete......://register.clinicaltrials.gov/by identifier: RESCueH_Relay NCT02188043 Project Relay Model for Recruiting Alcohol Dependent Patients in General Hospitals (TRN Registration: 07/09/2014)....

Improper Signaling for Virtual Full-Duplex Relay Systems

KAUST Repository

Gaafar, Mohamed; Amin, Osama; Schaefer, Rafael F.; Alouini, Mohamed-Slim

2017-01-01

Virtual full-duplex (VFD) is a powerful solution to compensate the rate loss of half-duplex relaying without the need to full-duplex capable nodes. Inter-relay interference (IRI) challenges the operation of VFD relaying systems. Recently, improper signaling is employed at both relays of the VFD to mitigate the IRI by imposing the same signal characteristics for both relays. To further boost the achievable rate performance, asymmetric time sharing VFD relaying system is adopted with different improper signals at the half-duplex relays. The joint tuning of the three design parameters improves the achievable rate performance at different ranges of IRI and different relays locations. Extensive simulation results are presented and analyzed to show the achievable rate gain of the proposed system and understand the system behavior.

Improper Signaling for Virtual Full-Duplex Relay Systems

KAUST Repository

Gaafar, Mohamed

2017-02-14

Virtual full-duplex (VFD) is a powerful solution to compensate the rate loss of half-duplex relaying without the need to full-duplex capable nodes. Inter-relay interference (IRI) challenges the operation of VFD relaying systems. Recently, improper signaling is employed at both relays of the VFD to mitigate the IRI by imposing the same signal characteristics for both relays. To further boost the achievable rate performance, asymmetric time sharing VFD relaying system is adopted with different improper signals at the half-duplex relays. The joint tuning of the three design parameters improves the achievable rate performance at different ranges of IRI and different relays locations. Extensive simulation results are presented and analyzed to show the achievable rate gain of the proposed system and understand the system behavior.

Speech-to-Speech Relay Service

Science.gov (United States)

Consumer Guide Speech to Speech Relay Service Speech-to-Speech (STS) is one form of Telecommunications Relay Service (TRS). TRS is a service that allows persons with hearing and speech disabilities ...

30 CFR 75.1713-3 - First-Aid training; supervisory employees.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false First-Aid training; supervisory employees. 75... First-Aid training; supervisory employees. The mine operator shall conduct first-aid training courses... employee and date on which the employee satisfactorily completed the first-aid training course. The...

Outage performance of two-way DF relaying systems with a new relay selection metric

KAUST Repository

Hyadi, Amal

2012-04-01

This paper investigates a new constrained relay selection scheme for two-way relaying systems where two end terminals communicate simultaneously via a relay. The introduced technique is based on the maximization of the weighted sum rate of both users. To evaluate the performance of the proposed system, the outage probability is derived in a general case (where an arbitrary channel is considered), and then over independently but not necessarily identically distributed (i.n.i.d.) Rayleigh fading channels. The analytical results are verified through simulations. © 2012 IEEE.

Improper signaling in two-path relay channels

KAUST Repository

Gaafar, Mohamed

2017-07-03

Inter-relay interference (IRI) challenges the operation of two-path relaying systems. Furthermore, the unavailability of the channel state information (CSI) at the source and the limited detection capabilities at the relays prevent neither eliminating the interference nor adopting joint detection at the relays nodes. Improper signaling is a powerful signaling scheme that has the capability to reduce the interference impact at the receiver side and improves the achievable rate performance. Therefore, improper signaling is adopted at both relays, which have access to the global CSI. Then, improper signal characteristics are designed to maximize the total end-to-end achievable rate at the relays. To this end, both the power and the circularity coefficient, a measure of the impropriety degree of the signal, are optimized at the relays. Although the optimization problem is not convex, optimal power allocation for both relays for a fixed circularity coefficient is obtained. Moreover, the circularity coefficient is tuned to maximize the rate for a given power allocation. Finally, a joint solution of the optimization problem is proposed using a coordinate descent method based on alternate optimization. The simulation results show that employing improper signaling improves the achievable rate at medium and high IRI.

Improper signaling in two-path relay channels

KAUST Repository

Gaafar, Mohamed; Amin, Osama; Schaefer, Rafael F.; Alouini, Mohamed-Slim

2017-01-01

Inter-relay interference (IRI) challenges the operation of two-path relaying systems. Furthermore, the unavailability of the channel state information (CSI) at the source and the limited detection capabilities at the relays prevent neither eliminating the interference nor adopting joint detection at the relays nodes. Improper signaling is a powerful signaling scheme that has the capability to reduce the interference impact at the receiver side and improves the achievable rate performance. Therefore, improper signaling is adopted at both relays, which have access to the global CSI. Then, improper signal characteristics are designed to maximize the total end-to-end achievable rate at the relays. To this end, both the power and the circularity coefficient, a measure of the impropriety degree of the signal, are optimized at the relays. Although the optimization problem is not convex, optimal power allocation for both relays for a fixed circularity coefficient is obtained. Moreover, the circularity coefficient is tuned to maximize the rate for a given power allocation. Finally, a joint solution of the optimization problem is proposed using a coordinate descent method based on alternate optimization. The simulation results show that employing improper signaling improves the achievable rate at medium and high IRI.

Commercial grade item (CGI) dedication of MDR relays for nuclear safety related applications

Science.gov (United States)

Das, Ranjit K.; Julka, Anil; Modi, Govind

1994-08-01

MDR relays manufactured by Potter & Brumfield (P&B) have been used in various safety related applications in commercial nuclear power plants. These include emergency safety features (ESF) actuation systems, emergency core cooling systems (ECCS) actuation, and reactor protection systems. The MDR relays manufactured prior to May 1990 showed signs of generic failure due to corrosion and outgassing of coil varnish. P&B has made design changes to correct these problems in relays manufactured after May 1990. However, P&B does not manufacture the relays under any 10CFR50 Appendix B quality assurance (QA) program. They manufacture the relays under their commercial QA program and supply these as commercial grade items. This necessitates CGI Dedication of these relays for use in nuclear-safety-related applications. This paper presents a CGI dedication program that has been used to dedicate the MDR relays manufactured after been used to dedicate the MDR relays manufactured after May 1990. The program is in compliance with current Nuclear Regulatory Commission (NRC) and Electric Power Research Institute (EPRI) guidelines and applicable industry standards; it specifies the critical characteristics of the relays, provides the tests and analysis required to verify the critical characteristics, the acceptance criteria for the test results, performs source verification to quality P&B for its control of the critical characteristics, and provides documentation. The program provides reasonable assurance that the new MDR relays will perform their intended safety functions.

Relay self interference minimisation using tapped filter

KAUST Repository

Jazzar, Saleh

2013-05-01

In this paper we introduce a self interference (SI) estimation and minimisation technique for amplify and forward relays. Relays are used to help forward signals between a transmitter and a receiver. This helps increase the signal coverage and reduce the required transmitted signal power. One problem that faces relays communications is the leaked signal from the relay\\'s output to its input. This will cause an SI problem where the new received signal at the relay\\'s input will be added with the unwanted leaked signal from the relay\\'s output. A Solution is proposed in this paper to estimate and minimise this SI which is based upon using a tapped filter at the destination. To get the optimum weights for this tapped filter, some channel parameters must be estimated first. This is performed blindly at the destination without the need of any training. This channel parameter estimation method is named the blind-self-interference-channel-estimation (BSICE) method. The next step in the proposed solution is to estimate the tapped filter\\'s weights. This is performed by minimising the mean squared error (MSE) at the destination. This proposed method is named the MSE-Optimum Weight (MSE-OW) method. Simulation results are provided in this paper to verify the performance of BSICE and MSE-OW methods. © 2013 IEEE.

Development and control of a three-axis satellite simulator for the bifocal relay mirror initiative

OpenAIRE

Chernesky, Vincent S.

2001-01-01

The Three Axis Satellite Simulator (TASS) is a 4-foot diameter octagonal platform supported on a spherical air bearing. The platform hosts several satellite subsystems, including rate gyros, reaction wheels, thrusters, sun sensors, and an onboard control computer. This free-floating design allows for realistic emulation of satellite attitude dynamics in a laboratory environment. The bifocal relay mirror spacecraft system is composed of two optically coupled telescopes used to redirect the las...

On the achievable degrees of freedom of alternate MIMO relaying with multiple AF relays

KAUST Repository

Park, Kihong; Alouini, Mohamed-Slim; Park, Seongho; Ko, Youngchai

2012-01-01

In this paper, we consider a two-hop relaying network where one source, one destination, and multiple amplify-and-forward (AF) relays equipped with M antennas operate in a half-duplex mode. In order to compensate for the inherent loss of capacity

Iterative Relay Scheduling with Hybrid ARQ under Multiple User Equipment (Type II) Relay Environments

KAUST Repository

Nam, Sung Sik; Alouini, Mohamed-Slim; Choi, Seyeong

2018-01-01

-generation cellular systems (e.g., LTE-Advanced and beyond). The proposed IRS-HARQ aims to increase the achievable data rate by iteratively scheduling a relatively better UE relay closer to the end user in a probabilistic sense, provided that the relay-to-end user

Multiple relay selection for delay-limited applications

KAUST Repository

Alsharoa, Ahmad M.

2013-12-01

A multiple relay selection system model that implements the decode-and-forward mode is investigated. All communication nodes are assumed to be equipped by multiple antennas. Furthermore, lattices space-time coded multiple-input multiple-output half duplex channel is applied. The main goal is to increase the throughput of the system by selecting multiple number of relays. The selection criteria depends on the maximum decoding delay at relays where the system implements a decoding time-out algorithm at each relay. This leads to a significant saving in the overall system power consumptions and attempts to solve the relays synchronization problem. All results are presented using numerical simulations. © 2012 IEEE.

Apple interface for experimental instrumentation and control-Pulse counter, timer, digital-to-analog converter, step motor and relays

International Nuclear Information System (INIS)

Souza, J.H.; Cernicchiaro, G.R.C.; Cavalcante, J.T.P.D.

1989-01-01

An interface plate for Apple II type microcomputer developed aiming to automatize measuring systems in which a TTL pulse counter, output of analogic voltage (with resolution of 12 bits), out put of step-motor control, relay drive, and timer for real time control, are necessary to carry-out the parallel tasks, is described. An application of this plate to a thermoluminescence reader is also presented. (M.C.K.) [pt

Airborne relay-based regional positioning system.

Science.gov (United States)

Lee, Kyuman; Noh, Hongjun; Lim, Jaesung

2015-05-28

Ground-based pseudolite systems have some limitations, such as low vertical accuracy, multipath effects and near-far problems. These problems are not significant in airborne-based pseudolite systems. However, the monitoring of pseudolite positions is required because of the mobility of the platforms on which the pseudolites are mounted, and this causes performance degradation. To address these pseudolite system limitations, we propose an airborne relay-based regional positioning system that consists of a master station, reference stations, airborne relays and a user. In the proposed system, navigation signals are generated from the reference stations located on the ground and are relayed via the airborne relays. Unlike in conventional airborne-based systems, the user in the proposed system sequentially estimates both the locations of airborne relays and his/her own position. Therefore, a delay due to monitoring does not occur, and the accuracy is not affected by the movement of airborne relays. We conducted several simulations to evaluate the performance of the proposed system. Based on the simulation results, we demonstrated that the proposed system guarantees a higher accuracy than airborne-based pseudolite systems, and it is feasible despite the existence of clock offsets among reference stations.

Bilayer expurgated LDPC codes with uncoded relaying

Directory of Open Access Journals (Sweden)

Md. Noor-A-Rahim

2017-08-01

Full Text Available Bilayer low-density parity-check (LDPC codes are an effective coding technique for decode-and-forward relaying, where the relay forwards extra parity bits to help the destination to decode the source bits correctly. In the existing bilayer coding scheme, these parity bits are protected by an error correcting code and assumed reliably available at the receiver. We propose an uncoded relaying scheme, where the extra parity bits are forwarded to the destination without any protection. Through density evolution analysis and simulation results, we show that our proposed scheme achieves better performance in terms of bit erasure probability than the existing relaying scheme. In addition, our proposed scheme results in lower complexity at the relay.

A SDP based design of relay precoding for the power minimization of MIMO AF-relay networks

KAUST Repository

Rao, Anlei

2015-09-11

Relay precoding for multiple-input and multiple-output (MIMO) relay networks has been approached by either optimizing the efficiency performance with given power consumption constraints or minimizing the power consumption with quality-of-service (QoS) requirements. For the later type design, previous works has worked on minimizing the approximated power consumption. In this paper, exact power consumption for all relays is derived into a quadratic form by diagonalizing the minimum-square error (MSE) matrix, and the relay precoding matrix is designed by optimizing this quadratic form with the help of semidefinite programming (SDP) relaxation. Our simulation results show that such a design can achieve a gain of around 3 dB against the previous design, which optimized the approximated power consumption. © 2015 IEEE.

Opportunistic Relay Selection with Cooperative Macro Diversity

Directory of Open Access Journals (Sweden)

Yu Chia-Hao

2010-01-01

Full Text Available We apply a fully opportunistic relay selection scheme to study cooperative diversity in a semianalytical manner. In our framework, idle Mobile Stations (MSs are capable of being used as Relay Stations (RSs and no relaying is required if the direct path is strong. Our relay selection scheme is fully selection based: either the direct path or one of the relaying paths is selected. Macro diversity, which is often ignored in analytical works, is taken into account together with micro diversity by using a complete channel model that includes both shadow fading and fast fading effects. The stochastic geometry of the network is taken into account by having a random number of randomly located MSs. The outage probability analysis of the selection differs from the case where only fast fading is considered. Under our framework, distribution of the received power is formulated using different Channel State Information (CSI assumptions to simulate both optimistic and practical environments. The results show that the relay selection gain can be significant given a suitable amount of candidate RSs. Also, while relay selection according to incomplete CSI is diversity suboptimal compared to relay selection based on full CSI, the loss in average throughput is not too significant. This is a consequence of the dominance of geometry over fast fading.

Opportunistic Fixed Gain Bidirectional Relaying with Outdated CSI

KAUST Repository

Khan, Fahd Ahmed; Tourki, Kamel; Alouini, Mohamed-Slim; Qaraqe, Khalid A.

2015-01-01

In a network with multiple relays, relay selection has been shown as an effective scheme to achieve diversity as well as to improve the overall throughput. This paper studies the impact of using outdated channel state information for relay selection on the performance of a network where two sources communicate with each other via fixed-gain amplify-and-forward relays. For a Rayleigh faded channel, closed-form expressions for the outage probability, moment generating function and symbol error rate are derived. Simulations results are also presented to corroborate the derived analytical results. It is shown that adding relays does not improve the performance if the channel is substantially outdated. Furthermore, relay location is also taken into consideration and it is shown that the performance can be improved by placing the relay closer to the source whose channel is more outdated. © 2015 IEEE.

Opportunistic Fixed Gain Bidirectional Relaying with Outdated CSI

KAUST Repository

Khan, Fahd Ahmed

2015-05-01

In a network with multiple relays, relay selection has been shown as an effective scheme to achieve diversity as well as to improve the overall throughput. This paper studies the impact of using outdated channel state information for relay selection on the performance of a network where two sources communicate with each other via fixed-gain amplify-and-forward relays. For a Rayleigh faded channel, closed-form expressions for the outage probability, moment generating function and symbol error rate are derived. Simulations results are also presented to corroborate the derived analytical results. It is shown that adding relays does not improve the performance if the channel is substantially outdated. Furthermore, relay location is also taken into consideration and it is shown that the performance can be improved by placing the relay closer to the source whose channel is more outdated. © 2015 IEEE.

MaROS Strategic Relay Planning and Coordination Interfaces

Science.gov (United States)

Allard, Daniel A.

2010-01-01

The Mars Relay Operations Service (MaROS) is designed to provide planning and analysis tools in support of ongoing Mars Network relay operations. Strategic relay planning requires coordination between lander and orbiter mission ground data system (GDS) teams to schedule and execute relay communications passes. MaROS centralizes this process, correlating all data relevant to relay coordination to provide a cohesive picture of the relay state. Service users interact with the system through thin-layer command line and web user interface client applications. Users provide and utilize data such as lander view periods of orbiters, Deep Space Network (DSN) antenna tracks, and reports of relay pass performance. Users upload and download relevant relay data via formally defined and documented file structures including some described in Extensible Markup Language (XML). Clients interface with the system via an http-based Representational State Transfer (ReST) pattern using Javascript Object Notation (JSON) formats. This paper will provide a general overview of the service architecture and detail the software interfaces and considerations for interface design.

Impaired Job Performance and Critical Incidents: Factors Influencing Supervisory EAP Referrals.

Science.gov (United States)

Harley, David A.

Relatively little empirical research has been done on the supervisory referral of employees to employee assistance programs (EAPs). Inclusion of constructive confrontation (supervisory referral) into program standards and its continued promotion as a "central strategy" of program theory and operation calls for critical investigation of…

Relay selection from an effective capacity perspective

KAUST Repository

Yang, Yuli

2013-09-01

In this work, we consider a cooperative network where multiple relay nodes having different modulation capabilities assist the end-to-end communication between a source and its destination. Firstly, we evaluate the effective capacity (EC) performance of the network under study. According to the analysis, an EC-based relay selection criterion is proposed. Based on the proposed selection rule and half-duplex decode-and-forward protocol, the activated relays cooperatively help with the packet transmission from the source. At the destination, packet combining is taken into account to improve the quality of service. Compared to the popular scheme, opportunistic relay selection, numerical results are provided to prove the validity and advantages of our proposed scheme in certain scenarios. Moreover, the analysis presented herein offers a convenient tool to the relaying transmission design, specifically on which relay selection scheme should be used as well as how to choose the receiving strategy between with and without packet combining at the destination. © 2013 IEEE.

CERN Relay Race 2009

CERN Document Server

2009-01-01

The CERN relay race will take place around the Meyrin site on Thursday 14th May starting at 12:15. If possible, please avoid driving on the site during this 20-minute period. If you do meet runners while driving your car, please STOP until they have all passed. Thank you for your cooperation. More details on how to register your team for the relay race

CERN Relay Race

CERN Multimedia

2011-01-01

The CERN relay race will take place around the Meyrin site on Thursday 19 May starting at 12-15. If possible, please avoid driving on the site during this 20-minute period. If you do meet runners while driving your car, please STOP until they have all passed. Thank you for your cooperation. Details of the course and of how to register your team for the relay race can be found here. Some advice for all runners from the Medical Service can also be found here.   

A low complexity algorithm for multiple relay selection in two-way relaying Cognitive Radio networks

KAUST Repository

Alsharoa, Ahmad M.

2013-06-01

In this paper, a multiple relay selection scheme for two-way relaying cognitive radio network is investigated. We consider a cooperative Cognitive Radio (CR) system with spectrum sharing scenario using Amplify-and-Forward (AF) protocol, where licensed users and unlicensed users operate on the same frequency band. The main objective is to maximize the sum rate of the unlicensed users allowed to share the spectrum with the licensed users by respecting a tolerated interference threshold. A practical low complexity heuristic approach is proposed to solve our formulated optimization problem. Selected numerical results show that the proposed algorithm reaches a performance close to the performance of the optimal multiple relay selection scheme either with discrete or continuous power distributions while providing a considerable saving in terms of computational complexity. In addition, these results show that our proposed scheme significantly outperforms the single relay selection scheme. © 2013 IEEE.

Elevator Group Supervisory Control System Using Genetic Network Programming with Macro Nodes and Reinforcement Learning

Science.gov (United States)

Zhou, Jin; Yu, Lu; Mabu, Shingo; Hirasawa, Kotaro; Hu, Jinglu; Markon, Sandor

Elevator Group Supervisory Control System (EGSCS) is a very large scale stochastic dynamic optimization problem. Due to its vast state space, significant uncertainty and numerous resource constraints such as finite car capacities and registered hall/car calls, it is hard to manage EGSCS using conventional control methods. Recently, many solutions for EGSCS using Artificial Intelligence (AI) technologies have been reported. Genetic Network Programming (GNP), which is proposed as a new evolutionary computation method several years ago, is also proved to be efficient when applied to EGSCS problem. In this paper, we propose an extended algorithm for EGSCS by introducing Reinforcement Learning (RL) into GNP framework, and an improvement of the EGSCS' performances is expected since the efficiency of GNP with RL has been clarified in some other studies like tile-world problem. Simulation tests using traffic flows in a typical office building have been made, and the results show an actual improvement of the EGSCS' performances comparing to the algorithms using original GNP and conventional control methods. Furthermore, as a further study, an importance weight optimization algorithm is employed based on GNP with RL and its efficiency is also verified with the better performances.

Quantum cryptography with an ideal local relay

DEFF Research Database (Denmark)

Spedalieri, Gaetana; Ottaviani, Carlo; Braunstein, Samuel L.

2015-01-01

We consider two remote parties connected to a relay by two quantum channels. To generate a secret key, they transmit coherent states to the relay, where the states are subject to a continuous-variable (CV) Bell detection. We study the ideal case where Alice's channel is lossless, i.e., the relay ...

A SDP based design of relay precoding for the power minimization of MIMO AF-relay networks

KAUST Repository

Rao, Anlei; Park, Kihong; Alouini, Mohamed-Slim

2015-01-01

Relay precoding for multiple-input and multiple-output (MIMO) relay networks has been approached by either optimizing the efficiency performance with given power consumption constraints or minimizing the power consumption with quality-of-service (Qo

User Multiplexing in Relay Enhanced LTE-Advanced Networks

DEFF Research Database (Denmark)

Teyeb, Oumer Mohammed; Frederiksen, Frank; Redana, Simone

2010-01-01

is radio relaying. This uses relay nodes that act as surrogate base stations for mobile users whose radio links with the base stations are not experiencing good enough conditions. In the downlink, the data that is destined for the relayed users may first have to be multiplexed by the base station, sent...... over the wireless backhaul link towards the relay node, and de-multiplexed and forwarded to the individual users by the relay node. The reverse process also has to be undertaken in the uplink. In this paper, we present a novel multiplexing scheme which is able to adapt the addressing and bitmapping...... of user identification to the actual number of users being served by the relay nodes, and thus greatly reduce the multiplexing overhead....

Areva - Press release from the Supervisory Board

International Nuclear Information System (INIS)

Marie, Patricia; Briand, Pauline; Floquet-Daubigeon, Fleur; Michaut, Maxime; Scorbiac, Marie de; Repaire, Philippine du

2012-01-01

During its meeting held on December 12, 2011, devoted in particular to the examination of the 2011 closing estimates, the AREVA Executive Board indicated that it expected to book a provision of 1.46 billion euros (2.025 billion US dollars) in the company's accounts for fiscal year 2011 for impairment of assets for the reporting entity UraMin, a mining company acquired by AREVA in 2007, which, given the provision booked in 2010 (426 million euros), brings the value of these assets on the AREVA balance sheet down to 410 million euros. Given the size of these provisions, the Supervisory Board decided to make three of its members, meeting as an ad hoc committee, in charge of analyzing the terms of acquisition of this company, as well as the key decisions made in this reporting entity up to 2011 and, based on the outcome of these analyses, to recommend to it any appropriate measures in AREVA's interest. This committee reported on its work during the Supervisory Board meeting held on February 14, 2012. In light of this report, the Supervisory Board found that the fairness and reliability of the financial statements of previous years were not in question. Nevertheless, considering the malfunctions raised, the Board considers it appropriate to thoroughly review AREVA's governance in order to ensure that decisions concerning large acquisitions or investments be reviewed and validated in the future under conditions ensuring better legal and financial security and enabling a more transparent dialogue between management and the Supervisory Board. It thus asked the Executive Board to recommend, at the next General Meeting of Shareholders, that the by-laws of the company be modified to make the Supervisory Board's prior approval of investments, stake acquisitions and acquisitions mandatory above a threshold of 20 million euros. It also decided to set up a business ethics committee within the Supervisory Board responsible for ensuring that rules of conduct are properly applied

Amplify-and-forward relaying in wireless communications

CERN Document Server

Rodriguez, Leonardo Jimenez; Le-Ngoc, Tho

2015-01-01

This SpringerBrief explores the advantage of relaying techniques in addressing the increasing demand for high data rates and reliable services over the air. It demonstrates how to design cost-effective relay systems that provide high spectral efficiency and fully exploit the diversity of the relay channel. The brief covers advances in achievable rates, power allocation schemes, and error performance for half-duplex (HD) and full-duplex (FD) amplify-and-forward (AF) single-relay systems. The authors discuss the capacity and respective optimal power allocation for a wide range of HD protocols ov

Full-Duplex Relay Selection in Cognitive Underlay Networks

KAUST Repository

Khafagy, Mohammad Galal

2017-09-30

In this work, we analyze the performance of full-duplex relay selection (FDRS) in spectrum-sharing networks. Contrary to half-duplex relaying, full-duplex relaying (FDR) enables simultaneous listening/forwarding at the secondary relay(s), thereby allowing for a higher spectral efficiency. However, since the source and relay simultaneously transmit in FDR, their superimposed signal at the primary receiver should now satisfy the existing interference constraint, which can considerably limit the secondary network throughput. In this regard, relay selection can offer an adequate solution to boost the secondary throughput while satisfying the imposed interference limit. We first analyze the performance of opportunistic FDRS with residual self-interference (RSI) by deriving the exact cumulative distribution function of its end-to-end signal-to-interference-plus-noise ratio under Nakagami-m fading. We also evaluate the offered diversity gain of relay selection for different full-duplex cooperation schemes in the presence/absence of a direct source-destination link. When the adopted RSI link gain model is sublinear in the relay power, which agrees with recent research findings, we show that remarkable diversity gain can be recovered even in the presence of an interfering direct link. Second, we evaluate the end-to-end performance of FDRS with interference constraints due to the presence of a primary receiver. Finally, the presented exact theoretical findings are verified by numerical simulations.

Relay exchanges in elite short track speed skating.

Science.gov (United States)

Hext, Andrew; Heller, Ben; Kelley, John; Goodwill, Simon

2017-06-01

In short track speed skating, the relay exchange provides an additional strategic component to races by allowing a team to change the skater involved in the pack race. Typically executed every 1½ laps, it is the belief of skaters and coaches that during this period of the race, time can be gained or lost due to the execution of the relay exchange. As such, the aim of this study was to examine the influence of the relay exchange on a team's progression through a 5000 m relay race. Using data collected from three World Cup relay events during the 2012-2013 season, the time taken to complete the straight for the scenarios with and without the relay exchange were compared at different skating speeds for the corner exit prior to the straight. Overall, the influence of the relay exchange was found to be dependent on this corner exit speed. At slower corner exit speeds (12.01-13.5 m/s), relay exchange straight times were significantly faster than the free skating scenario (P < 0.01). While at faster corner exit speeds (14.01-15 m/s), straight times were significantly slower (P < 0.001). The findings of this study suggest that the current norm of executing relay exchanges every 1½ laps may not be optimal. Instead, varying the frequency of relay exchange execution throughout the race could allow: (1) time to be gained relative to other teams; and (2) facilitate other race strategies by providing an improved opportunity to overtake.

On Alternate Relaying with Improper Gaussian Signaling

KAUST Repository

Gaafar, Mohamed; Amin, Osama; Ikhlef, Aissa; Chaaban, Anas; Alouini, Mohamed-Slim

2016-01-01

In this letter, we investigate the potential benefits of adopting improper Gaussian signaling (IGS) in a two-hop alternate relaying (AR) system. Given the known benefits of using IGS in interference-limited networks, we propose to use IGS to relieve the inter-relay interference (IRI) impact on the AR system assuming no channel state information is available at the source. In this regard, we assume that the two relays use IGS and the source uses proper Gaussian signaling (PGS). Then, we optimize the degree of impropriety of the relays signal, measured by the circularity coefficient, to maximize the total achievable rate. Simulation results show that using IGS yields a significant performance improvement over PGS, especially when the first hop is a bottleneck due to weak source-relay channel gains and/or strong IRI.

On Alternate Relaying with Improper Gaussian Signaling

KAUST Repository

Gaafar, Mohamed

2016-06-06

In this letter, we investigate the potential benefits of adopting improper Gaussian signaling (IGS) in a two-hop alternate relaying (AR) system. Given the known benefits of using IGS in interference-limited networks, we propose to use IGS to relieve the inter-relay interference (IRI) impact on the AR system assuming no channel state information is available at the source. In this regard, we assume that the two relays use IGS and the source uses proper Gaussian signaling (PGS). Then, we optimize the degree of impropriety of the relays signal, measured by the circularity coefficient, to maximize the total achievable rate. Simulation results show that using IGS yields a significant performance improvement over PGS, especially when the first hop is a bottleneck due to weak source-relay channel gains and/or strong IRI.

Microprocessor protection relays: new prospects or new problems?

OpenAIRE

Gurevich, Vladimir

2006-01-01

The internal architecture and principles of operation of microprocessor-based devices including so-called "microprocessor protective relays" have little in common with devices called "electric relays". But microprocessor-based relay protection devices are gradually driving out the traditional electromechanical and even electronic relay protection of virtually from all fields of power and electrical engineering. Advantages of microprocessor-based protection means over traditional ones are far ...

Cognitive Relay Networks: A Comprehensive Survey

Directory of Open Access Journals (Sweden)

Ayesha Naeem

2015-07-01

Full Text Available Cognitive radio is an emerging technology to deal with the scarcity and requirement of radio spectrum by dynamically assigning spectrum to unlicensed user . This revolutionary technology shifts the paradigm in the wireless system design by all owing unlicensed user the ability to sense, adapt and share the dynamic spectrum. Cognitive radio technology have been applied to different networks and applications ranging from wireless to public saf ety, smart grid, medical, rela y and cellular applications to increase the throughput and spectrum efficiency of the network. Among these applications, cognitive relay networks is one of the application where cognitive radio technology has been applied. Cognitiv e rela y network increases the network throughput by reducing the complete pa th loss and also by ensuring cooper ation among secondary users and cooperation among primary and secondary users. In this paper , our aim is to provide a survey on cognitive relay network. We also provide a detailed review on existing schemes in cognitive relay networks on the basis of relaying protocol, relay cooperation and channel model.

Error-rate performance analysis of opportunistic regenerative relaying

KAUST Repository

Tourki, Kamel; Yang, Hongchuan; Alouini, Mohamed-Slim

2011-01-01

In this paper, we investigate an opportunistic relaying scheme where the selected relay assists the source-destination (direct) communication. In our study, we consider a regenerative opportunistic relaying scheme in which the direct path can

An airborne meteorological data collection system using satellite relay /ASDAR/

Science.gov (United States)

Bagwell, J. W.; Lindow, B. G.

1978-01-01

The paper describes the aircraft to satellite data relay (ASDAR) project which processes information collected by the navigation and data systems of widebody jet aircraft which cross data-sparse areas of the tropics and southern hemisphere. The ASDAR system consists of a data acquisition and control unit to acquire, store, and format latitude, longitude, altitude, wind speed, wind direction, and outside air temperature data; a transmitter to relay the formatted data via satellite to the ground; and a clock to time the data sampling and transmission periods.

Relay cropping as a sustainable approach: problems and opportunities for sustainable crop production.

Science.gov (United States)

Tanveer, Mohsin; Anjum, Shakeel Ahmad; Hussain, Saddam; Cerdà, Artemi; Ashraf, Umair

2017-03-01

Climate change, soil degradation, and depletion of natural resources are becoming the most prominent challenges for crop productivity and environmental sustainability in modern agriculture. In the scenario of conventional farming system, limited chances are available to cope with these issues. Relay cropping is a method of multiple cropping where one crop is seeded into standing second crop well before harvesting of second crop. Relay cropping may solve a number of conflicts such as inefficient use of available resources, controversies in sowing time, fertilizer application, and soil degradation. Relay cropping is a complex suite of different resource-efficient technologies, which possesses the capability to improve soil quality, to increase net return, to increase land equivalent ratio, and to control the weeds and pest infestation. The current review emphasized relay cropping as a tool for crop diversification and environmental sustainability with special focus on soil. Briefly, benefits, constraints, and opportunities of relay cropping keeping the goals of higher crop productivity and sustainability have also been discussed in this review. The research and knowledge gap in relay cropping was also highlighted in order to guide the further studies in future.

Non-linear model predictive supervisory controller for building, air handling unit with recuperator and refrigeration system with heat waste recovery

DEFF Research Database (Denmark)

Minko, Tomasz; Wisniewski, Rafal; Bendtsen, Jan Dimon

2016-01-01

. The retrieved heat excess can be stored in the water tank. For this purpose the charging and the discharging water loops has been designed. We present the non-linear model of the above described system and a non-linear model predictive supervisory controller that according to the received price signal......, occupancy information and ambient temperature minimizes the operation cost of the whole system and distributes set points to local controllers of supermarkets subsystems. We find that when reliable information about the high price period is available, it is profitable to use the refrigeration system...... to generate heat during the low price period, store it and use it to substitute the conventional heater during the high price period....

Using Software Zelio Soft in Educational Process to Simulation Control Programs for Intelligent Relays

Science.gov (United States)

Michalik, Peter; Mital, Dusan; Zajac, Jozef; Brezikova, Katarina; Duplak, Jan; Hatala, Michal; Radchenko, Svetlana

2016-10-01

Article deals with point to using intelligent relay and PLC systems in practice, to their architecture and principles of programming and simulations for education process on all types of school from secondary to universities. Aim of the article is proposal of simple examples of applications, where is demonstrated methodology of programming on real simple practice examples and shown using of chosen instructions. In practical part is described process of creating schemas and describing of function blocks, where are described methodologies of creating program and simulations of output reactions on changeable inputs for intelligent relays.

Relay protection features of frequency-adjustable electric drive

Science.gov (United States)

Kuprienko, V. V.

2018-03-01

The features of relay protection of high-voltage electric motors in composition of the frequency-adjustable electric drive are considered in the article. The influence of frequency converters on the stability of the operation of various types of relay protection used on electric motors is noted. Variants of circuits for connecting relay protection devices are suggested. The need to develop special relay protection devices for a frequency-adjustable electric drive is substantiated.

Relay Telecommunications for the Coming Decade of Mars Exploration

Science.gov (United States)

Edwards, C.; DePaula, R.

2010-01-01

Over the past decade, an evolving network of relay-equipped orbiters has advanced our capabilities for Mars exploration. NASA's Mars Global Surveyor, 2001 Mars Odyssey, and Mars Reconnaissance Orbiter (MRO), as well as ESA's Mars Express Orbiter, have provided telecommunications relay services to the 2003 Mars Exploration Rovers, Spirit and Opportunity, and to the 2007 Phoenix Lander. Based on these successes, a roadmap for continued Mars relay services is in place for the coming decade. MRO and Odyssey will provide key relay support to the 2011 Mars Science Laboratory (MSL) mission, including capture of critical event telemetry during entry, descent, and landing, as well as support for command and telemetry during surface operations, utilizing new capabilities of the Electra relay payload on MRO and the Electra-Lite payload on MSL to allow significant increase in data return relative to earlier missions. Over the remainder of the decade a number of additional orbiter and lander missions are planned, representing new orbital relay service providers and new landed relay users. In this paper we will outline this Mars relay roadmap, quantifying relay performance over time, illustrating planned support scenarios, and identifying key challenges and technology infusion opportunities.

Sum-Rate Enhancement in Multiuser MIMO Decode-and-Forward Relay Broadcasting Channel with Energy Harvesting Relays

KAUST Repository

Benkhelifa, Fatma

2016-09-20

In this paper, we consider a multiuser multipleinput multiple-output (MIMO) decode-and-forward (DF) relay broadcasting channel (BC) with single source, multiple energy harvesting (EH) relays and multiple destinations. All the nodes are equipped with multiple antennas. The EH and information decoding (ID) tasks at the relays and destinations are separated over the time, which is termed as the time switching (TS) scheme. As optimal solutions for the sum-rate maximization problems of BC channels and the MIMO interference channels are hard to obtain, the end-to-end sum rate maximization problem of a multiuser MIMO DF relay BC channel is even harder. In this paper, we propose to tackle a simplified problem where we employ the block diagonalization (BD) procedure at the source, and we mitigate the interference between the relaydestination channels using an algorithm similar to the BD method. In order to show the relevance of our low complex proposed solution, we compare it to the minimum mean-square error (MMSE) solution that was shown in the literature to be equivalent to the solution of the sum-rate maximization in MIMO broadcasting interfering channels. We also investigate the time division multiple access (TDMA) solution which separates all the information transmissions from the source to the relays and from the relays to the destinations over time. We provide numerical results to show the relevance of our proposed solution, in comparison with the no co-channel interference (CCI) case, the TDMA based solution and the MMSE based solution.

Sum-Rate Enhancement in Multiuser MIMO Decode-and-Forward Relay Broadcasting Channel with Energy Harvesting Relays

KAUST Repository

Benkhelifa, Fatma; Salem, Ahmed Sultan; Alouini, Mohamed-Slim

2016-01-01

In this paper, we consider a multiuser multipleinput multiple-output (MIMO) decode-and-forward (DF) relay broadcasting channel (BC) with single source, multiple energy harvesting (EH) relays and multiple destinations. All the nodes are equipped with multiple antennas. The EH and information decoding (ID) tasks at the relays and destinations are separated over the time, which is termed as the time switching (TS) scheme. As optimal solutions for the sum-rate maximization problems of BC channels and the MIMO interference channels are hard to obtain, the end-to-end sum rate maximization problem of a multiuser MIMO DF relay BC channel is even harder. In this paper, we propose to tackle a simplified problem where we employ the block diagonalization (BD) procedure at the source, and we mitigate the interference between the relaydestination channels using an algorithm similar to the BD method. In order to show the relevance of our low complex proposed solution, we compare it to the minimum mean-square error (MMSE) solution that was shown in the literature to be equivalent to the solution of the sum-rate maximization in MIMO broadcasting interfering channels. We also investigate the time division multiple access (TDMA) solution which separates all the information transmissions from the source to the relays and from the relays to the destinations over time. We provide numerical results to show the relevance of our proposed solution, in comparison with the no co-channel interference (CCI) case, the TDMA based solution and the MMSE based solution.

Evaluation of Harmonics Impact on Digital Relays

Directory of Open Access Journals (Sweden)

Kinan Wannous

2018-04-01

Full Text Available This paper presents the concept of the impact of harmonic distortion on a digital protection relay. The aim is to verify and determine the reasons of a mal-trip or failure to trip the protection relays; the suggested solution of the harmonic distortion is explained by a mathematical model in the Matlab Simulink programming environment. The digital relays have been tested under harmonic distortions in order to verify the function of the relays algorithm under abnormal conditions. The comparison between the protection relay algorithm under abnormal conditions and a mathematical model in the Matlab Simulink programming environment based on injected harmonics of high values is provided. The test is separated into different levels; the first level is based on the harmonic effect of an individual harmonic and mixed harmonics. The test includes the effect of the harmonics in the location of the fault point into distance protection zones. This paper is a new proposal in the signal processing of power quality disturbances using Matlab Simulink and the power quality impact on the measurements of the power system quantities; the test simulates the function of protection in power systems in terms of calculating the current and voltage values of short circuits and their faults. The paper includes several tests: frequency variations and decomposition of voltage waveforms with Fourier transforms (model and commercial relay, the effect of the power factor on the location of fault points, the relation between the tripping time and the total harmonic distortion (THD levels in a commercial relay, and a comparison of the THD capture between the commercial relay and the model.

Design of an advanced human-centered supervisory system for a nuclear fuel reprocessing system

International Nuclear Information System (INIS)

Riera, B.; Lambert, M.; Martel, G.

1999-01-01

In the field of highly automated processes, our research concerns supervisory system design adapted to supervisory and default diagnosis by human operators. The interpretation of decisional human behaviour models shows that the tasks of human operators require different information, which has repercussions on the supervisory system design. We propose an advanced human-centred supervisory system (AHCSS) which is more adapted to human-beings, because it integrates new representation of the production system,(such as functional and behavioural aspects) with the use of advanced algorithms of detection and location. Based on an approach using these new concepts, and AHCSS was created for a nuclear fuel reprocessing system. (authors)

Relay testing parametric investigation of seismic fragility

International Nuclear Information System (INIS)

Bandyopadhyay, K.; Hofmayer, C.; Kassir, M.; Pepper, S.

1989-01-01

The seismic capacity of most electrical equipment is governed by malfunction of relays. An evaluation of the existing relay test data base at Brookhaven National Laboratory (BNL) has indicated that the seismic fragility of a relay may depend on various parameters related to the design or the input motion. In particular, the electrical mode, contact state, adjustment, chatter duration acceptance limit, and the frequency and the direction of the vibration input have been considered to influence the relay fragility level. For a particular relay type, the dynamics of its moving parts depends on the exact model number and vintage and hence, these parameters may also influence the fragility level. In order to investigate the effect of most of these parameters on the seismic fragility level, BNL has conducted a relay test program. The testing has been performed at Wyle Laboratories. Establishing the correlation between the single frequency fragility test input and the corresponding multifrequency response spectrum (TRS) is also an objective of this test program. This paper discusses the methodology used for testing and presents a brief summary of important test results. 1 ref., 10 figs

Capacity Bounds and Mapping Design for Binary Symmetric Relay Channels

Directory of Open Access Journals (Sweden)

Majid Nasiri Khormuji

2012-12-01

Full Text Available Capacity bounds for a three-node binary symmetric relay channel with orthogonal components at the destination are studied. The cut-set upper bound and the rates achievable using decode-and-forward (DF, partial DF and compress-and-forward (CF relaying are first evaluated. Then relaying strategies with finite memory-length are considered. An efficient algorithm for optimizing the relay functions is presented. The Boolean Fourier transform is then employed to unveil the structure of the optimized mappings. Interestingly, the optimized relay functions exhibit a simple structure. Numerical results illustrate that the rates achieved using the optimized low-dimensional functions are either comparable to those achieved by CF or superior to those achieved by DF relaying. In particular, the optimized low-dimensional relaying scheme can improve on DF relaying when the quality of the source-relay link is worse than or comparable to that of other links.

Calibration and Evaluation of Fixed and Mobile Relay-Based System Level Simulator

Directory of Open Access Journals (Sweden)

Shahid Mumtaz

2010-01-01

Full Text Available Future wireless communication systems are expected to provide more stable and higher data rate transmissions in the whole OFDMA networks, but the mobile stations (MSs in the cell boundary experience poor spectral efficiency due to the path loss from the transmitting antenna and interference from adjacent cells. Therefore, satisfying QoS (Quality of Service requirements of each MS at the cell boundary has been an important issue. To resolve this spectral efficiency problem at the cell boundary, deploying relay stations has been actively considered. As multihop/relay has complex interactions between the routing and medium access control decisions, the extent to which analytical expressions can be used to explore its benefits is limited. Consequently, simulations tend to be the preferred way of assessing the performance of relays. In this paper, we evaluate the performance of relay-assisted OFDMA networks by means of system level simulator (SLS. We consistently observed that the throughput is increased and the outage is decreased in the relay-assisted OFDMA network, which is converted to range extension without any capacity penalty, for the realistic range of values of the propagation and other system parameters investigated.

Duplex Schemes in Multiple Antenna Two-Hop Relaying

Directory of Open Access Journals (Sweden)

Anja Klein

2008-04-01

Full Text Available A novel scheme for two-hop relaying defined as space division duplex (SDD relaying is proposed. In SDD relaying, multiple antenna beamforming techniques are applied at the intermediate relay station (RS in order to separate downlink and uplink signals of a bi-directional two-hop communication between two nodes, namely, S1 and S2. For conventional amplify-and-forward two-hop relaying, there appears a loss in spectral efficiency due to the fact that the RS cannot receive and transmit simultaneously on the same channel resource. In SDD relaying, this loss in spectral efficiency is circumvented by giving up the strict separation of downlink and uplink signals by either time division duplex or frequency division duplex. Two novel concepts for the derivation of the linear beamforming filters at the RS are proposed; they can be designed either by a three-step or a one-step concept. In SDD relaying, receive signals at S1 are interfered by transmit signals of S1, and receive signals at S2 are interfered by transmit signals of S2. An efficient method in order to combat this kind of interference is proposed in this paper. Furthermore, it is shown how the overall spectral efficiency of SDD relaying can be improved if the channels from S1 and S2 to the RS have different qualities.

Supervisory behavior, reciprocity and subordinate absenteeism

NARCIS (Netherlands)

Dierendonck, van D.; Blanc, Le P.M.; Breukelen, van W.

2002-01-01

The present study among 242 professionals working in a lung clinic and nursing home was designed to test a model that links supervisory behavior (i.e. leader member exchange (LMX) behavior and conflict management behavior) and reciprocity in the supervisor/subordinate relationship to objectively

Two-Hop Secure Communication Using an Untrusted Relay

Directory of Open Access Journals (Sweden)

Xiang He

2009-01-01

Full Text Available We consider a source-destination pair that can only communicate through an untrusted intermediate relay node. The intermediate node is willing to employ a designated relaying scheme to facilitate reliable communication between the source and the destination. Yet, the information it relays needs to be kept secret from it. In this two-hop communication scenario, where the use of the untrusted relay node is essential, we find that a positive secrecy rate is achievable. The center piece of the achievability scheme is the help provided by either the destination node with transmission capability, or an external “good samaritan” node. In either case, the helper performs cooperative jamming that confuses the eavesdropping relay and disables it from being able to decipher what it is relaying. We next derive an upper bound on the secrecy rate for this system. We observe that the gap between the upper bound and the achievable rate vanishes as the power of the relay node goes to infinity. Overall, the paper presents a case for intentional interference, that is, cooperative jamming, as an enabler for secure communication.

Energy-efficient relay selection and optimal power allocation for performance-constrained dual-hop variable-gain AF relaying

KAUST Repository

Zafar, Ammar; Radaydeh, Redha Mahmoud Mesleh; Chen, Yunfei; Alouini, Mohamed-Slim

2013-01-01

This paper investigates the energy-efficiency enhancement of a variable-gain dual-hop amplify-and-forward (AF) relay network utilizing selective relaying. The objective is to minimize the total consumed power while keeping the end-to-end signal

Application of a proposed overcurrent relay in radial distribution networks

Energy Technology Data Exchange (ETDEWEB)

Conde, A.; Vazquez, E. [Universidad Autonoma de Nuevo Leon, Facultad de Ingenieria Mecanica y Electrica, A.P. 36-F, CU, CP 66450, San Nicolas de los Garza, Nuevo Leon (Mexico)

2011-02-15

This paper contains the application criteria and coordination process for a proposed overcurrent relay in a radial power system with feed from one or multiple sources. This relay uses independent functions to detect faults and to calculate the operation time. Also this relay uses a time element function that allows it to reduce the time relay operation, enhancing the backup protection. Some of the proposed approaches improve the sensitivity of the relay. The selection of the best approach in the proposed relay is defined by the needs of the application. The proposed protection can be considered as an additional function protection to conventional overcurrent relays. (author)

Time of arrival based location estimation for cooperative relay networks

KAUST Repository

Ç elebi, Hasari Burak; Abdallah, Mohamed M.; Hussain, Syed Imtiaz; Qaraqe, Khalid A.; Alouini, Mohamed-Slim

2010-01-01

In this paper, we investigate the performance of a cooperative relay network performing location estimation through time of arrival (TOA). We derive Cramer-Rao lower bound (CRLB) for the location estimates using the relay network. The analysis is extended to obtain average CRLB considering the signal fluctuations in both relay and direct links. The effects of the channel fading of both relay and direct links and amplification factor and location of the relay node on average CRLB are investigated. Simulation results show that the channel fading of both relay and direct links and amplification factor and location of relay node affect the accuracy of TOA based location estimation. ©2010 IEEE.

Time of arrival based location estimation for cooperative relay networks

KAUST Repository

Çelebi, Hasari Burak

2010-09-01

In this paper, we investigate the performance of a cooperative relay network performing location estimation through time of arrival (TOA). We derive Cramer-Rao lower bound (CRLB) for the location estimates using the relay network. The analysis is extended to obtain average CRLB considering the signal fluctuations in both relay and direct links. The effects of the channel fading of both relay and direct links and amplification factor and location of the relay node on average CRLB are investigated. Simulation results show that the channel fading of both relay and direct links and amplification factor and location of relay node affect the accuracy of TOA based location estimation. ©2010 IEEE.

Full-Duplex opportunistic relay selection in future spectrum-sharing networks

KAUST Repository

Khafagy, Mohammad Galal; Alouini, Mohamed-Slim; Aï ssa, Sonia

2015-01-01

We propose and analyze the performance of full-duplex relay selection in primary/secondary spectrum-sharing networks. Contrary to half-duplex relaying, full-duplex relaying (FDR) enables simultaneous listening/forwarding at the secondary relay, thereby allowing for a higher spectral efficiency. However, since the source and relay simultaneously transmit in FDR, their superimposed signal at the primary receiver should now satisfy the existing interference constraint which can considerably limit the secondary network throughput. In this regard, relay selection can offer an adequate solution to boost the secondary throughput while satisfying the imposed interference limit. We first analyze the performance of opportunistic relay selection among a cluster of full-duplex decode-and-forward relays with self-interference by deriving the exact cumulative distribution function of its end-to-end signal-to-noise ratio. Second, we evaluate the end-to-end performance of relay selection with interference constraints due to the presence of a primary receiver. Finally, the presented exact theoretical findings are verified by numerical simulations.

Full-Duplex opportunistic relay selection in future spectrum-sharing networks

KAUST Repository

Khafagy, Mohammad Galal

2015-06-01

We propose and analyze the performance of full-duplex relay selection in primary/secondary spectrum-sharing networks. Contrary to half-duplex relaying, full-duplex relaying (FDR) enables simultaneous listening/forwarding at the secondary relay, thereby allowing for a higher spectral efficiency. However, since the source and relay simultaneously transmit in FDR, their superimposed signal at the primary receiver should now satisfy the existing interference constraint which can considerably limit the secondary network throughput. In this regard, relay selection can offer an adequate solution to boost the secondary throughput while satisfying the imposed interference limit. We first analyze the performance of opportunistic relay selection among a cluster of full-duplex decode-and-forward relays with self-interference by deriving the exact cumulative distribution function of its end-to-end signal-to-noise ratio. Second, we evaluate the end-to-end performance of relay selection with interference constraints due to the presence of a primary receiver. Finally, the presented exact theoretical findings are verified by numerical simulations.

Discrete radioisotopic relays of a cyclic action

International Nuclear Information System (INIS)

Klempner, K.S.; Vasil'ev, A.G.

1975-01-01

A functional diagram of discrete radioisotopic relay equipment (RRP) with cyclic action was examined. An analysis of its rapid action and reliability under stationary conditions and transition regimes is presented. A structural diagram of radioisotopic relay equipment shows three radiation detectors, a pulse standardizer, an integrator and a power amplifier with a threshold cut-off device. It was established that the basic properties of the RRP - rapid action and reliability - are determined entirely by the counting rate of the average frequency of pulses from the radiation detector, n 0 and n 1 , in the 0 and 1 states (absence of current in the electromagnetic relay winding and activation of the winding of the output relay), capacities N 1 and N 2 of the dual counters, and the frequency of the transition threshold, f, of the generator. Formulas are presented which allow making engineering calculations for determining the optimum RRP parameters. High speed and reliability are shown, which are determined by the production purposes of the relay

Asymmetric Modulation Gains in Network Coded Relay Networks

DEFF Research Database (Denmark)

Roetter, Daniel Enrique Lucani; Fitzek, Frank

2015-01-01

Wireless relays have usually been considered in two ways. On the one hand, a physical layer approach focused on per-packet reliability and involving the relay on each packet transmission. On the other, recent approaches have relied on the judicious activation of the relay at the network level to ...

Beamforming Design for Coordinated Direct and Relay Systems

DEFF Research Database (Denmark)

Sun, Fan; De Carvalho, Elisabeth; Thai, Chan

2012-01-01

Joint processing of multiple communication flows in wireless systems has given rise to a number of novel transmission techniques, notably the two-way relaying based on wireless network coding. Recently, a related set of techniques has emerged, termed coordinated direct and relay (CDR) transmissions......, where the constellation of traffic flows is more general than the two-way. Regardless of the actual traffic flows, in a CDR scheme the relay has a central role in managing the interference. In this paper we investigate the novel transmission modes, based on amplify-and-forward, that arise when the relay...... an iterative solution, as well as derive an upper performance bound. The numerical results demonstrate a clear benefit from usage of multiple antennas at the relay node....

State, space relay modeling and simulation using the electromagnetic Transients Program and its transient analysis of control systems capability

International Nuclear Information System (INIS)

Domijan, A.D. Jr.; Emami, M.V.

1990-01-01

This paper reports on a simulation of a MHO distance relay developed to study the effect of its operation under various system conditions. Simulation is accomplished using a state space approach and a modeling technique using ElectroMagnetic Transient Program (Transient Analysis of Control Systems). Furthermore, simulation results are compared with those obtained in another independent study as a control, to validate the results. A data code for the practical utilization of this simulation is given

Robust distributed cognitive relay beamforming

KAUST Repository

Pandarakkottilil, Ubaidulla

2012-05-01

In this paper, we present a distributed relay beamformer design for a cognitive radio network in which a cognitive (or secondary) transmit node communicates with a secondary receive node assisted by a set of cognitive non-regenerative relays. The secondary nodes share the spectrum with a licensed primary user (PU) node, and each node is assumed to be equipped with a single transmit/receive antenna. The interference to the PU resulting from the transmission from the cognitive nodes is kept below a specified limit. The proposed robust cognitive relay beamformer design seeks to minimize the total relay transmit power while ensuring that the transceiver signal-to-interference- plus-noise ratio and PU interference constraints are satisfied. The proposed design takes into account a parameter of the error in the channel state information (CSI) to render the performance of the beamformer robust in the presence of imperfect CSI. Though the original problem is non-convex, we show that the proposed design can be reformulated as a tractable convex optimization problem that can be solved efficiently. Numerical results are provided and illustrate the performance of the proposed designs for different network operating conditions and parameters. © 2012 IEEE.

Ubiquitous Supervisory System Based on Social Contexts Using Ontology

Directory of Open Access Journals (Sweden)

Satoru Izumi

2009-01-01

Full Text Available As described in this paper, we propose a supervisory system that considers actual situations and social aspects of users in a ubiquitous computing environment. To realize gentle and safe supervision while providing efficient supervisory services, the system must recognize the situations of a watched person, such as the person's physical condition. To achieve this, we have proposed a ubiquitous supervisory system "uEyes", which introduces Social Context Awareness: a distinguishing feature for supervision. Using this feature, the system can combine environmental information acquired from sensors in the real world and common-sense knowledge related to human activities in daily life. As described in this paper, we specifically examine design of Social Context Awareness using ontology technologies. Based on this advanced feature, a live video streaming system is configured autonomously depending on the users' circumstances in runtime. We implemented a uEyes prototype for supervising elderly people and performed some experiments based on several scenarios. Based on those experimental results, we confirmed that the social contexts are handled effectively to support the supervision.

Relay tracking control for second-order multi-agent systems with damaged agents.

Science.gov (United States)

Dong, Lijing; Li, Jing; Liu, Qin

2017-11-01

This paper investigates a situation where smart agents capable of sensory and mobility are deployed to monitor a designated area. A preset number of agents start tracking when a target intrudes this area. Some of the tracking agents are possible to be out of order over the tracking course. Thus, we propose a cooperative relay tracking strategy to ensure the successful tracking with existence of damaged agents. Relay means that, when a tracking agent quits tracking due to malfunction, one of the near deployed agents replaces it to continue the tracking task. This results in jump of tracking errors and dynamic switching of topology of the multi-agent system. Switched system technique is employed to solve this specific problem. Finally, the effectiveness of proposed tracking strategy and validity of the theoretical results are verified by conducting a numerical simulation. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

Asymptotic analysis for Nakagami-m fading channels with relay selection

KAUST Repository

Zhong, Caijun

2011-06-01

In this paper, we analyze the asymptotic outage probability performance of both decode-and-forward (DF) and amplify-and-forward (AF) relaying systems using partial relay selection and the "best" relay selection schemes for Nakagami-m fading channels. We derive their respective outage probability expressions in the asymptotic high signal-to-noise ratio (SNR) regime, from which the diversity order and coding gain are analyzed. In addition, we investigate the impact of power allocation between the source and relay terminals and derive the diversity-multiplexing tradeoff (DMT) for these relay selection systems. The theoretical findings suggest that partial relay selection can improve the diversity of the system and can achieve the same DMT as the "best" relay selection scheme under certain conditions. © 2011 IEEE.

LTE-Advanced Relay Technology and Standardization

CERN Document Server

Yuan, Yifei

2013-01-01

LTE-Advanced Relay Technology and Standardization provides a timely reference work for relay technology with the finalizing of LTE Release 10 specifications. LTE-Advanced is quickly becoming the global standard for 4G cellular communications. The relay technology, as one of the key features in LTE-Advanced, helps not only to improve the system coverage and capacity, but also to save the costs of laying wireline backhaul. As a leading researcher in the field of LTE-Advanced standards, the author provides an in-depth description of LTE-A relay technology, and explains in detail the standard specification and design principles.     Readers from both academic and industrial fields can find sections of interest to them: Sections 2 & 4 could benefit researchers in academia and those who are engaged in exploratory work, while Sections 3 & 4 are more useful to engineers. Dr. Yifei Yuan is the Technical Director at the Standards Department of ZTE Inc.

New results on performance analysis of opportunistic regenerative relaying

KAUST Repository

Tourki, Kamel; Yang, Hongchuan; Alouini, Mohamed-Slim; Qaraqe, Khalid A.

2013-01-01

In this paper, we investigate an opportunistic relaying scheme where the selected relay assists the source-destination (direct) communication. In our study, we consider a regenerative opportunistic relaying scheme in which the direct path may

Accurate performance analysis of opportunistic decode-and-forward relaying

KAUST Repository

Tourki, Kamel; Yang, Hongchuan; Alouini, Mohamed-Slim

2011-01-01

In this paper, we investigate an opportunistic relaying scheme where the selected relay assists the source-destination (direct) communication. In our study, we consider a regenerative opportunistic relaying scheme in which the direct path may

Electric equipment technical regulation on a relay

International Nuclear Information System (INIS)

1995-01-01

It is about a relay for power protection. It describes the definitions of structure, a point of contact protection of contact, reclosing, relay scheme and input circuit. It explains normal use condition, special use condition, rated frequency, rated voltage and rated current, fluctuation range of permission of incoming relay. It deals with general structing outer case, correction device, operation indicator and outer terminal condition sort and method of the test. It adds the marks and pictures about currents

Commercial Grade Item (CGI) Dedication for Leak Detection Relays

International Nuclear Information System (INIS)

KOCH, M.R.; JOHNS, B.R.

1999-01-01

This Test Plan provides a test method to dedicate the leak detection relays used on the new Pumping and Instrumentation Control (PIC) skids. The new skids are fabricated on-site. The leak detection system is a safety class system per the Authorization Basis

Relay Protection and Automation Systems Based on Programmable Logic Integrated Circuits

International Nuclear Information System (INIS)

Lashin, A. V.; Kozyrev, A. V.

2015-01-01

One of the most promising forms of developing the apparatus part of relay protection and automation devices is considered. The advantages of choosing programmable logic integrated circuits to obtain adaptive technological algorithms in power system protection and control systems are pointed out. The technical difficulties in the problems which today stand in the way of using relay protection and automation systems are indicated and a new technology for solving these problems is presented. Particular attention is devoted to the possibility of reconfiguring the logic of these devices, using programmable logic integrated circuits

Performance of hybrid-ARQ with incremental redundancy over relay channels

KAUST Repository

Chelli, Ali

2012-12-01

In this paper, we consider a relay network consisting of a source, a relay, and a destination. The source transmits a message to the destination using hybrid automatic repeat request (HARQ) with incremental redundancy (IR). The relay overhears the transmitted messages over the different HARQ rounds and tries to decode the data packet. In case of successful decoding at the relay, both the relay and the source cooperate to transmit the message to the destination. A maximum number M of HARQ rounds is considered. The channel realizations are independent for different HARQ rounds. We assume Rayleigh fading channels for the links source-relay, source-destination, and relay-destination. We investigate the performance of HARQ-IR over relay channel from an information theoretic perspective. Analytical expressions are derived for the information outage probability, the average number of transmissions, and the average transmission rate. We illustrate through our investigation the benefit of relaying. We also show the impact of the target outage probability and the maximum number M of HARQ rounds on the outage probability, the average number of transmissions, and the average transmission rate. © 2012 IEEE.

Review of the first line supervisory positions in nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

Mullin, D; Mackenzie, C W [Hickling Corp. (Canada)

1995-10-01

The authors review the nature of the tasks performed by first line maintenance supervisors in three nuclear power plants. They compare these tasks to core supervisory training curriculum, supervisory job descriptions, and both the process related to performance appraisals, and the criteria applied in carrying out these performance evaluations. Recommendations have been made concerning methods of increasing the relevancy of training and improving the performance appraisal process. ( author). 5 figs.

Review of the first line supervisory positions in nuclear power plants

International Nuclear Information System (INIS)

Mullin, D.; Mackenzie, C.W.

1995-10-01

The authors review the nature of the tasks performed by first line maintenance supervisors in three nuclear power plants. They compare these tasks to core supervisory training curriculum, supervisory job descriptions, and both the process related to performance appraisals, and the criteria applied in carrying out these performance evaluations. Recommendations have been made concerning methods of increasing the relevancy of training and improving the performance appraisal process. ( author). 5 figs

Protective relaying theory and applications

CERN Document Server

Elmore, Walter A

2003-01-01

Targeting the latest microprocessor technologies for more sophisticated applications in the field of power system short circuit detection, this revised and updated source imparts fundamental concepts and breakthrough science for the isolation of faulty equipment and minimization of damage in power system apparatus. The Second Edition clearly describes key procedures, devices, and elements crucial to the protection and control of power system function and stability. It includes chapters and expertise from the most knowledgeable experts in the field of protective relaying, and describes micropro

The Case for Deep Space Telecommunications Relay Stations

Science.gov (United States)

Chandler, Charles W.; Miranda, Felix A. (Technical Monitor)

2004-01-01

Each future mission to Jupiter and beyond must carry the traditional suite of telecommunications systems for command and control and for mission data transmission to earth. The telecommunications hardware includes the large antenna and the high-power transmitters that enable the communications link. Yet future spacecraft will be scaled down from the hallmark missions of Galileo and Cassini to Jupiter and Saturn, respectively. This implies that a higher percentage of the spacecraft weight and power must be dedicated to telecommunications system. The following analysis quantifies this impact to future missions and then explores the merits of an alternative approach using deep space relay stations for the link back to earth. It will be demonstrated that a telecommunications relay satellite would reduce S/C telecommunications weight and power sufficiently to add one to two more instruments.

On Buffer-Aided Multiple-Access Relay Channel

DEFF Research Database (Denmark)

Liu, Rongkuan; Popovski, Petar; Wang, Gang

2016-01-01

This letter treats uplink scenario where M user equipments (UEs) send to a base station (BS), possibly via a common relay station (RS) that is equipped with a buffer. This is a multiple-access relay channel aided by a buffer. We devise a protocol in which the transmission mode is selected...... entirely at the BS, while simultaneously a number of UEs sends new messages to the BS. The results show that the adaptive selection of direct and buffer-aided relay transmissions leads to significant average throughput gains....

Cooperative AF Relaying in Spectrum-Sharing Systems: Outage Probability Analysis under Co-Channel Interferences and Relay Selection

KAUST Repository

Xia, Minghua

2012-11-01

For cooperative amplify-and-forward (AF) relaying in spectrum-sharing wireless systems, secondary users share spectrum resources originally licensed to primary users to communicate with each other and, thus, the transmit power of secondary transmitters is strictly limited by the tolerable interference powers at primary receivers. Furthermore, the received signals at a relay and at a secondary receiver are inevitably interfered by the signals from primary transmitters. These co-channel interferences (CCIs) from concurrent primary transmission can significantly degrade the performance of secondary transmission. This paper studies the effect of CCIs on outage probability of the secondary link in a spectrum-sharing environment. In particular, in order to compensate the performance loss due to CCIs, the transmit powers of a secondary transmitter and its relaying node are respectively optimized with respect to both the tolerable interference powers at the primary receivers and the CCIs from the primary transmitters. Moreover, when multiple relays are available, the technique of opportunistic relay selection is exploited to further improve system performance with low implementation complexity. By analyzing lower and upper bounds on the outage probability of the secondary system, this study reveals that it is the tolerable interference powers at primary receivers that dominate the system performance, rather than the CCIs from primary transmitters. System designers will benefit from this result in planning and designing next-generation broadband spectrum-sharing systems.

Relay self interference minimisation using tapped filter

KAUST Repository

Jazzar, Saleh; Al-Naffouri, Tareq Y.

2013-01-01

In this paper we introduce a self interference (SI) estimation and minimisation technique for amplify and forward relays. Relays are used to help forward signals between a transmitter and a receiver. This helps increase the signal coverage

On the Coded Packet Relay Network in the Presence of Neighbors

DEFF Research Database (Denmark)

Khamfroush, Hana; Pahlevani, Peyman; Roetter, Daniel Enrique Lucani

2014-01-01

This paper studies the problem of optimal use of a relay for reducing the transmission time of data packets from a source to a destination using network coding. More importantly, we address an effect that is typically overlooked in previous studies: the presence of active transmitting nodes...... in the neighborhood of such devices, which is typical in wireless mesh networks. We show that in systems with a fair medium access control mechanism (MAC), the use of a relay in a crowded medium brings forth considerable and unforeseen improvements, including up to 3.5x gains in terms of throughput compared to using...... only the direct link in some of our examples, and a considerable extension of the operating region where using a relay is beneficial. The problem is formulated as a Markov Decision Process (MDP) and numerical results are provided comparing simple, close–to–optimal heuristics to the optimal scheme....

Relay selection from an effective capacity perspective

KAUST Repository

Yang, Yuli; Ma, Hao; Aï ssa, Sonia

2013-01-01

proposed scheme in certain scenarios. Moreover, the analysis presented herein offers a convenient tool to the relaying transmission design, specifically on which relay selection scheme should be used as well as how to choose the receiving strategy between

76 FR 72124 - Internet-Based Telecommunications Relay Service Numbering

Science.gov (United States)

2011-11-22

... Docket No. 10-191; FCC 11-123] Internet-Based Telecommunications Relay Service Numbering AGENCY: Federal..., the information collection associated with the Commission's Internet- Based Telecommunications Relay... Telecommunications Relay Service Numbering, CG Docket No. 03-123; WC Docket No. 05-196; WC Docket No. 10-191; FCC 11...

Using a micromachined magnetostatic relay in commutating a DC motor

Science.gov (United States)

Tai, Yu-Chong (Inventor); Wright, John A. (Inventor); Lilienthal, Gerald (Inventor)

2004-01-01

A DC motor is commutated by rotating a magnetic rotor to induce a magnetic field in at least one magnetostatic relay in the motor. Each relay is activated in response to the magnetic field to deliver power to at least one corresponding winding connected to the relay. In some cases, each relay delivers power first through a corresponding primary winding and then through a corresponding secondary winding to a common node. Specific examples include a four-pole, three-phase motor in which each relay is activated four times during one rotation of the magnetic rotor.

Relay-assited transmission and radio resource management for wireless networks

OpenAIRE

Agustín de Dios, Adrián

2008-01-01

La transmisión asistida por relay o transmisión cooperativa es una nueva técnica de diversidad espacial donde aparece un elemento nuevo (un relay o un usuario cooperativo) en la tradicional transmisión punto a punto (fuente a destino). Ahora en la comunicación intervienen tres enlaces: fuente-relay, relay-destino y fuente-destino. El relay, además de asistir a la fuente en la transmisión de un mensaje, permite combatir las degradaciones que puede sufrir el canal como el shadowing y el pathlos...

Optimized Policies for Improving Fairness of Location-based Relay Selection

DEFF Research Database (Denmark)

Nielsen, Jimmy Jessen; Olsen, Rasmus Løvenstein; Madsen, Tatiana Kozlova

2013-01-01

For WLAN systems in which relaying is used to improve throughput performance for nodes located at the cell edge, node mobility and information collection delays can have a significant impact on the performance of a relay selection scheme. In this paper we extend our existing Markov Chain modeling...... framework for relay selection to allow for efficient calculation of relay policies given either mean throughput or kth throughput percentile as optimization criterium. In a scenario with static access point, static relay, and a mobile destination node, the kth throughput percentile optimization...

Generalized instantly decodable network coding for relay-assisted networks

KAUST Repository

Elmahdy, Adel M.

2013-09-01

In this paper, we investigate the problem of minimizing the frame completion delay for Instantly Decodable Network Coding (IDNC) in relay-assisted wireless multicast networks. We first propose a packet recovery algorithm in the single relay topology which employs generalized IDNC instead of strict IDNC previously proposed in the literature for the same relay-assisted topology. This use of generalized IDNC is supported by showing that it is a super-set of the strict IDNC scheme, and thus can generate coding combinations that are at least as efficient as strict IDNC in reducing the average completion delay. We then extend our study to the multiple relay topology and propose a joint generalized IDNC and relay selection algorithm. This proposed algorithm benefits from the reception diversity of the multiple relays to further reduce the average completion delay in the network. Simulation results show that our proposed solutions achieve much better performance compared to previous solutions in the literature. © 2013 IEEE.

7 CFR 1717.611 - RUS approval of expenditures for legal, accounting, engineering, and supervisory services.

Science.gov (United States)

2010-01-01

..., supervisory (other than for the management and operation of the borrower's electric system, see § 1717.608(d... 7 Agriculture 11 2010-01-01 2010-01-01 false RUS approval of expenditures for legal, accounting... COMMON TO INSURED AND GUARANTEED ELECTRIC LOANS Operational Controls § 1717.611 RUS approval of...

Physical-Layer Security of a Buffer-Aided Full-Duplex Relaying System

KAUST Repository

El Shafie, Ahmed

2016-07-07

This letter proposes a novel hybrid half-/full-duplex relaying scheme to enhance the relay channel security. A source node (Alice) communicates with her destination node (Bob) in the presence of a buffer-aided full-duplex relay node (Rooney) and a potential eavesdropper (Eve). Rooney adopts two different relaying, namely randomize-and-forward and decode-andforward relaying strategies, to improve the security of the legitimate system. In the first relaying strategy, Rooney uses a codebook different from that used at Alice. In the second relaying strategy, Rooney and Alice use the same codebooks. In addition, Rooney switches between half-duplex and full-duplex modes to further enhance the security of the legitimate system. The numerical results demonstrate that our proposed scheme achieves a significant average secrecy end-to-end throughput improvement relative to the conventional bufferless full-duplex relaying scheme.

Optimal Contract Design for Cooperative Relay Incentive Mechanism under Moral Hazard

Directory of Open Access Journals (Sweden)

Nan Zhao

2015-01-01

Full Text Available Cooperative relay can effectively improve spectrum efficiency by exploiting the spatial diversity in the wireless networks. However, wireless nodes may acquire different network information with various users’ location and mobility, channels’ conditions, and other factors, which results in asymmetric information between the source and the relay nodes (RNs. In this paper, the relay incentive mechanism between relay nodes and the source is investigated under the asymmetric information. By modelling multiuser cooperative relay as a labour market, a contract model with moral hazard for relay incentive is proposed. To effectively incentivize the potential RNs to participate in cooperative relay, the optimization problems are formulated to maximize the source’s utility while meeting the feasible conditions under both symmetric and asymmetric information scenarios. Numerical simulation results demonstrate the effectiveness of the proposed contract design scheme for cooperative relay.

Physical-Layer Security of a Buffer-Aided Full-Duplex Relaying System

KAUST Repository

El Shafie, Ahmed; Salem, Ahmed Sultan; Al-Dhahir, Naofal

2016-01-01

This letter proposes a novel hybrid half-/full-duplex relaying scheme to enhance the relay channel security. A source node (Alice) communicates with her destination node (Bob) in the presence of a buffer-aided full-duplex relay node (Rooney) and a potential eavesdropper (Eve). Rooney adopts two different relaying, namely randomize-and-forward and decode-andforward relaying strategies, to improve the security of the legitimate system. In the first relaying strategy, Rooney uses a codebook different from that used at Alice. In the second relaying strategy, Rooney and Alice use the same codebooks. In addition, Rooney switches between half-duplex and full-duplex modes to further enhance the security of the legitimate system. The numerical results demonstrate that our proposed scheme achieves a significant average secrecy end-to-end throughput improvement relative to the conventional bufferless full-duplex relaying scheme.

Cooperative jamming power control to enhance secrecy communications of AF Relaying systems for Rayleigh fading channel

KAUST Repository

Park, Kihong

2012-09-01

In this paper, we investigate secrecy communications in two-hop wireless relaying networks which consist of one source, one amplify-and-forward (AF) relay, one legitimate destination, and one eavesdropper. To prevent the eavesdropper from intercepting the source message, we make the destination send the intended noise to the AF relay during the first phase. This is referred to as cooperative jamming. According to the channel information at the destination, we address two types of jamming power allocation; (i) rate-optimal power allocation and (ii) outage-optimal power allocation. More specifically, without the instantaneous channel knowledge for the eavesdropper side, the outage probability of the secrecy rate is minimized with respect to the intended noise power level. We show that the outage-optimal allocation gives almost the same outage probability as the rateoptimal one. In addition, the jamming power consumption can be significantly reduced compared to the fixed and rate-optimal power allocation methods. © 2012 IEEE.

A performance analysis in AF full duplex relay selection network

Science.gov (United States)

Ngoc, Long Nguyen; Hong, Nhu Nguyen; Loan, Nguyen Thi Phuong; Kieu, Tam Nguyen; Voznak, Miroslav; Zdralek, Jaroslav

2018-04-01

This paper studies on the relaying selective matter in amplify-and-forward (AF) cooperation communication with full-duplex (FD) activity. Various relay choice models supposing the present of different instant information are investigated. We examine a maximal relaying choice that optimizes the instant FD channel capacity and asks for global channel state information (CSI) as well as partial CSI learning. To make comparison easy, accurate outage probability clauses and asymptote form of these strategies that give a diversity rank are extracted. From that, we can see clearly that the number of relays, noise factor, the transmittance coefficient as well as the information transfer power had impacted on their performance. Besides, the optimal relay selection (ORS) model can promote than that of the partial relay selection (PRS) model.

STUDI ANALISIS KOORDINASI OVER CURRENT RELAY (OCR DAN GROUND FAULT RELAY (GFR PADA RECLOSER DI SALURAN PENYULANG PENEBEL

Directory of Open Access Journals (Sweden)

I Dewa Gde Agung Budhi Udiana

2017-08-01

Full Text Available Short circuit causing over current problem and can might causing interference of the equipment performance such as distribution transformers also causing widespread disruption occurred. In resolving such interference is required as protection system on the distribution system. Seeing all above is needed coordination between the supporting component of the protection system which is consisted of Over Current Relay (OCR and Ground Fault Relay (GFR. The research was conducted at PT. PLN (Persero South Bali Area Network, INDONESIA on recloser in the feeder line of Penebel. OCR setting between the Relay feeder of Penebel, Recloser Celagi, Recloser Bakisan, and Recloser Benana still less selective, with time value coordination between average security was still less than 0,2 second. Then OCR setting and GFR relay feeder of Penebel, Recloser Celagi, Recloser Bakisan, and Recloser Benana was recommended for re-setting in order to minimize disruption and electric power distribution system to be reliable.

Two-way CSI-assisted AF relaying with HPA nonlinearity

KAUST Repository

Qi, Jian

2015-09-11

In this paper, we investigate half-duplex two-way dual-hop channel state information (CSI)-assisted amplify-andforward (AF) relaying in the presence of high-power amplifier (HPA) nonlinearity at relays. The expression for the end-toend signal-to-noise ratio (SNR) is derived as per the modified system model by taking into account the interference caused by relaying scheme and HPA nonlinearity. The system performance of the considered relaying network is evaluated in terms of average symbol error probability (SEP) in Nakagami-m fading channels, by making use of the moment-generating function (MGF) approach. Numerical results are provided and show the effects of several parameters, such as quadrature amplitude modulation (QAM) order, number of relays, HPA parameters, and Nakagami parameter, on performance. © 2015 IEEE.

Spreading Sequence System for Full Connectivity Relay Network

Science.gov (United States)

Kwon, Hyuck M. (Inventor); Yang, Jie (Inventor); Pham, Khanh D. (Inventor)

2018-01-01

Fully connected uplink and downlink fully connected relay network systems using pseudo-noise spreading and despreading sequences subjected to maximizing the signal-to-interference-plus-noise ratio. The relay network systems comprise one or more transmitting units, relays, and receiving units connected via a communication network. The transmitting units, relays, and receiving units each may include a computer for performing the methods and steps described herein and transceivers for transmitting and/or receiving signals. The computer encodes and/or decodes communication signals via optimum adaptive PN sequences found by employing Cholesky decompositions and singular value decompositions (SVD). The PN sequences employ channel state information (CSI) to more effectively and more securely computing the optimal sequences.

Four-Way Relaying in Wireless Cellular Systems

DEFF Research Database (Denmark)

Liu, Huaping; Popovski, Petar; De Carvalho, Elisabeth

2013-01-01

Two-way relaying in wireless systems has initiated a large research effort during the past few years. Nevertheless, it represents only a specific traffic pattern and it is of interest to investigate other traffic patterns where such a simultaneous processing of information flows can bring...... performance advantage. In this paper we consider a \\emph{four-way relaying} scenario, where each of the two Mobile Stations (MSs) has a two-way connection to the same Base Station (BS), while each connection is through a dedicated Relay Station (RS). The RSs are placed in such a way that one RS...... of the new scheme for Decode-and-Forward (DF) operational model for the RS. We compare the performance with a state-of-the-art reference scheme, based on two-way relaying with DF. The results indicate that the achievable rate regions are significantly enlarged for the new scheme....

Systematic Network Coding with the Aid of a Full-Duplex Relay

DEFF Research Database (Denmark)

Giacaglia, Giuliano; Shi, Xiaomeng; Kim, MinJi

2013-01-01

is to deliver a given number of data packets to a receiver with the aid of a relay. The source broadcasts to both the receiver and the relay using one frequency, while the relay uses another frequency for transmissions to the receiver, allowing for a full-duplex operation of the relay. We analyze the decoding...... complexity and delay performance of two types of relays: one that preserves the systematic structure of the code from the source; another that does not. A systematic relay forwards uncoded packets upon reception, but transmits coded packets to the receiver after receiving the first coded packet from...

Mobile User Connectivity in Relay-Assisted Visible Light Communications

Directory of Open Access Journals (Sweden)

Petr Pešek

2018-04-01

Full Text Available In this paper, we investigate relay-assisted visible light communications (VLC where a mobile user acts as a relay and forwards data from a transmitter to the end mobile user. We analyse the utilization of the amplify-and-forward (AF and decode-and-forward (DF relaying schemes. The focus of the paper is on analysis of the behavior of the mobile user acting as a relay while considering a realistic locations of the receivers and transmitters on a standard mobile phone, more specifically with two photodetectors on both sides of a mobile phone and a transmitting LED array located upright. We also investigate dependency of the bit error rate (BER performance on the azimuth and elevation angles of the mobile relay device within a typical office environment. We provide a new analytical description of BER for AF and DF-based relays in VLC. In addition we compare AF and DF-based systems and show that DF offers a marginal improvement in the coverage area with a BER < 10–3 and a data rate of 100 Mb/s. Numerical results also illustrate that relay-based systems offer a significant improvement in terms of the coverage compared to direct non-line of sight VLC links.

47 CFR 11.20 - State Relay Network.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 1 2010-10-01 2010-10-01 false State Relay Network. 11.20 Section 11.20... Network. This network is composed of State Relay (SR) sources, leased common carrier communications facilities or any other available communication facilities. The network distributes State EAS messages...

Implementation of EPICS based vacuum control system for variable energy cyclotron centre, Kolkata

Science.gov (United States)

Roy, Anindya; Bhole, R. B.; Nandy, Partha P.; Yadav, R. C.; Pal, Sarbajit; Roy, Amitava

2015-03-01

The vacuum system of the Room Temperature (K = 130) Cyclotron of Variable Energy Cyclotron Centre is comprised of vacuum systems of main machine and Beam Transport System. The vacuum control system is upgraded to a PLC based Automated system from the initial relay based Manual system. The supervisory control of the vacuum system is implemented in Experimental Physics and Industrial Control System (EPICS). An EPICS embedded ARM based vacuum gauge controller is developed to mitigate the requirement of vendor specific gauge controller for gauges and also for seamless integration of the gauge controllers with the control system. A set of MS-Windows ActiveX components with embedded EPICS Channel Access interface are developed to build operator interfaces with less complex programming and to incorporate typical Windows feature, e.g., user authentication, file handling, better fonts, colors, mouse actions etc. into the operator interfaces. The control parameters, monitoring parameters, and system interlocks of the system are archived in MySQL based EPICS MySQL Archiver developed indigenously. In this paper, we describe the architecture, the implementation details, and the performance of the system.

Implementation of EPICS based vacuum control system for variable energy cyclotron centre, Kolkata

Energy Technology Data Exchange (ETDEWEB)

Roy, Anindya, E-mail: r-ani@vecc.gov.in; Bhole, R. B.; Nandy, Partha P.; Yadav, R. C.; Pal, Sarbajit; Roy, Amitava [Variable Energy Cyclotron Centre, 1/AF Bidhan Nagar, Kolkata 700064 (India)

2015-03-15

The vacuum system of the Room Temperature (K = 130) Cyclotron of Variable Energy Cyclotron Centre is comprised of vacuum systems of main machine and Beam Transport System. The vacuum control system is upgraded to a PLC based Automated system from the initial relay based Manual system. The supervisory control of the vacuum system is implemented in Experimental Physics and Industrial Control System (EPICS). An EPICS embedded ARM based vacuum gauge controller is developed to mitigate the requirement of vendor specific gauge controller for gauges and also for seamless integration of the gauge controllers with the control system. A set of MS-Windows ActiveX components with embedded EPICS Channel Access interface are developed to build operator interfaces with less complex programming and to incorporate typical Windows feature, e.g., user authentication, file handling, better fonts, colors, mouse actions etc. into the operator interfaces. The control parameters, monitoring parameters, and system interlocks of the system are archived in MySQL based EPICS MySQL Archiver developed indigenously. In this paper, we describe the architecture, the implementation details, and the performance of the system.

Implementation of EPICS based vacuum control system for variable energy cyclotron centre, Kolkata

International Nuclear Information System (INIS)

Roy, Anindya; Bhole, R. B.; Nandy, Partha P.; Yadav, R. C.; Pal, Sarbajit; Roy, Amitava

2015-01-01

The vacuum system of the Room Temperature (K = 130) Cyclotron of Variable Energy Cyclotron Centre is comprised of vacuum systems of main machine and Beam Transport System. The vacuum control system is upgraded to a PLC based Automated system from the initial relay based Manual system. The supervisory control of the vacuum system is implemented in Experimental Physics and Industrial Control System (EPICS). An EPICS embedded ARM based vacuum gauge controller is developed to mitigate the requirement of vendor specific gauge controller for gauges and also for seamless integration of the gauge controllers with the control system. A set of MS-Windows ActiveX components with embedded EPICS Channel Access interface are developed to build operator interfaces with less complex programming and to incorporate typical Windows feature, e.g., user authentication, file handling, better fonts, colors, mouse actions etc. into the operator interfaces. The control parameters, monitoring parameters, and system interlocks of the system are archived in MySQL based EPICS MySQL Archiver developed indigenously. In this paper, we describe the architecture, the implementation details, and the performance of the system

Supervisory Turnover in Outpatient Substance Abuse Treatment

Science.gov (United States)

Knight, Danica K.; Broome, Kirk M.; Edwards, Jennifer R.; Flynn, Patrick M.

2009-01-01

Staff turnover is a significant issue within substance abuse treatment, with implications for service delivery and organizational health. This study examined factors associated with turnover among supervisors in outpatient substance abuse treatment. Turnover was conceptualized as being an individual response to organizational-level influences, and predictors represent aggregate program measures. Participants included 532 staff (including 467 counselors and 65 clinical/program directors) from 90 programs in four regions of the USA. Using logistic regression, analyses of structural factors indicated that programs affiliated with a parent organization and those providing more counseling hours to clients had higher turnover rates. When measures of job attitudes were included, only parent affiliation and collective appraisal of satisfaction were related to turnover. Subsequent analyses identified a trend toward increased supervisory turnover when satisfaction was low following the departure of a previous supervisor. These findings suggest that organizational-level factors can be influential in supervisory turnover. PMID:19949883

SIMULASI SISTEM KELISTRIKAN KAMAR HOTEL MENGGUNAKAN SMART RELAY

Directory of Open Access Journals (Sweden)

I Nyoman Sukarma

2018-03-01

Full Text Available Fungsi dari alat key tag atau hotel switch atau key card adalah memutus atau menyambungkan aliran listrik ke dalam suatu area tertentu atau ruang. Key tag memiliki peran penting pada kamar hotel untuk mencegah pemborosan energi pada saat kamar hotel tidak berpenghuni atau belum tersewakan. Untuk itu, penulis merancang simulasi sistem kelistrikan pada kamar hotel yang dikontrol dengan smart relay. Pada simulasi ini digunakan smart relay Zelio Logic buatan Schneider Electric. Pemrograman smart relay ini menggunakan ladder diagram yang disusun menggunakan perangkat lunak ZelioSoft2 dari Schneider Electric. Smart relay menerima sinyal masukan dari sensor, key tag dan sakelar. Sinyal masukan tersebut selanjutnya diproses agar lampu, kotak-kontak, exhaust fan, dan AC (Air Conditioner pada kamar hotel dapat bekerja.

Research on Real-Time Supervisory System for Compaction Quality in Face Rockfill Dam Engineering

Directory of Open Access Journals (Sweden)

Shengxiang Huang

2018-01-01

Full Text Available Compaction quality control in filling construction is of great significance to the stability and durability of the face rockfill dam. The conventional method of quality control mainly relies on manual process control and inspection for a limited number of test holes, which cannot meet the high requirements of modern mechanized construction and schedule anymore, with increasing of scale of face rockfill dams. There is an urgent need to propose a new quality control method of face rockfill dams during the entire compaction process. In this paper, a supervisory system based on GNSS (Global Navigation Satellite System technology, wireless data communication technology, Internet of things technology, and computer technology is developed to supervise the real-time roller compaction parameters of the working surface including rolling track, rolling times, rolling speed, thickness, and smoothness. The system obtains continuous and high-precision spatial position information of roller compaction machines through GNSS technology and then calculates the roller compaction parameter information. The compaction quality control for the face rockfill dam is achieved through the supervision of roller compaction parameters. The feasibility and robustness of the developed supervisory system are validated by a case study in the face rockfill dam of Shuibuya project in China. The practice shows that the system provides a new and effective method of process control for the construction quality of the roller compaction in dam engineering and realizes real-time, precision, and automatic supervising of roller compaction parameters and ensures better construction quality.

Performance of hybrid-ARQ with incremental redundancy over relay channels

KAUST Repository

Chelli, Ali; Alouini, Mohamed-Slim

2012-01-01

In this paper, we consider a relay network consisting of a source, a relay, and a destination. The source transmits a message to the destination using hybrid automatic repeat request (HARQ) with incremental redundancy (IR). The relay overhears

Asymptotic analysis for Nakagami-m fading channels with relay selection

KAUST Repository

Zhong, Caijun; Wong, Kaikit; Jin, Shi; Alouini, Mohamed-Slim; Ratnarajah, Tharm

2011-01-01

In this paper, we analyze the asymptotic outage probability performance of both decode-and-forward (DF) and amplify-and-forward (AF) relaying systems using partial relay selection and the "best" relay selection schemes for Nakagami-m fading channels

Efficient Resource Scheduling by Exploiting Relay Cache for Cellular Networks

Directory of Open Access Journals (Sweden)

Chun He

2015-01-01

Full Text Available In relay-enhanced cellular systems, throughput of User Equipment (UE is constrained by the bottleneck of the two-hop link, backhaul link (or the first hop link, and access link (the second hop link. To maximize the throughput, resource allocation should be coordinated between these two hops. A common resource scheduling algorithm, Adaptive Distributed Proportional Fair, only ensures that the throughput of the first hop is greater than or equal to that of the second hop. But it cannot guarantee a good balance of the throughput and fairness between the two hops. In this paper, we propose a Two-Hop Balanced Distributed Scheduling (TBS algorithm by exploiting relay cache for non-real-time data traffic. The evolved Node Basestation (eNB adaptively adjusts the number of Resource Blocks (RBs allocated to the backhaul link and direct links based on the cache information of relays. Each relay allocates RBs for relay UEs based on the size of the relay UE’s Transport Block. We also design a relay UE’s ACK feedback mechanism to update the data at relay cache. Simulation results show that the proposed TBS can effectively improve resource utilization and achieve a good trade-off between system throughput and fairness by balancing the throughput of backhaul and access link.

Supervisory Monitoring of Workplace at CIAE in 2011

Institute of Scientific and Technical Information of China (English)

无

2011-01-01

1 Introduction Based on The Routine Monitoring Programme for Workplace at CIAE in 2011 which approved by Division of Safe and Environmental Protection, a management sector of China Institute of Atomic Energy (CIAE), supervisory monitoring of

Wireless Energy Harvesting Two-Way Relay Networks with Hardware Impairments.

Science.gov (United States)

Peng, Chunling; Li, Fangwei; Liu, Huaping

2017-11-13

This paper considers a wireless energy harvesting two-way relay (TWR) network where the relay has energy-harvesting abilities and the effects of practical hardware impairments are taken into consideration. In particular, power splitting (PS) receiver is adopted at relay to harvests the power it needs for relaying the information between the source nodes from the signals transmitted by the source nodes, and hardware impairments is assumed suffered by each node. We analyze the effect of hardware impairments [-20]on both decode-and-forward (DF) relaying and amplify-and-forward (AF) relaying networks. By utilizing the obtained new expressions of signal-to-noise-plus-distortion ratios, the exact analytical expressions of the achievable sum rate and ergodic capacities for both DF and AF relaying protocols are derived. Additionally, the optimal power splitting (OPS) ratio that maximizes the instantaneous achievable sum rate is formulated and solved for both protocols. The performances of DF and AF protocols are evaluated via numerical results, which also show the effects of various network parameters on the system performance and on the OPS ratio design.

Two-Way Multi-Antenna Relaying with Simultaneous Wireless Information and Power Transfer

Directory of Open Access Journals (Sweden)

Thanaphat Srivantana

2017-03-01

Full Text Available In this paper, we propose various kinds of two-way multi-antenna relaying with simultaneous wireless information and power transfer (SWIPT and investigate their performance. Specifically, we first consider a two-way relay network where two single-antenna end nodes communicate with each other through a multi-antenna relay node that is energy constrained. This relay node harvests energy from the two end nodes and use the harvested energy for forwarding their information. Six relaying schemes that support the considered network then build on the power splitting-based relaying and time switching-based relaying protocols. The average bit error rates of these schemes are evaluated and compared by computer simulations considering several network parameters, including the number of relay antennas, power splitting ratio, and energy harvesting time. Such evaluation and comparison provide useful insights into the performance of SWIPT-based two-way multi-antenna relaying.

An RSS based location estimation technique for cognitive relay networks

KAUST Repository

Qaraqe, Khalid A.; Hussain, Syed Imtiaz; Ç elebi, Hasari Burak; Abdallah, Mohamed M.; Alouini, Mohamed-Slim

2010-01-01

In this paper, a received signal strength (RSS) based location estimation method is proposed for a cooperative wireless relay network where the relay is a cognitive radio. We propose a method for the considered cognitive relay network to determine

Breaking the Myth That Relay Swimming Is Faster Than Individual Swimming.

Science.gov (United States)

Skorski, Sabrina; Etxebarria, Naroa; Thompson, Kevin G

2016-04-01

To investigate if swimming performance is better in a relay race than in the corresponding individual race. The authors analyzed 166 elite male swimmers from 15 nations in the same competition (downloaded from www.swimrankings.net). Of 778 observed races, 144 were Olympic Games performances (2000, 2004, 2012), with the remaining 634 performed in national or international competitions. The races were 100-m (n = 436) and 200-m (n = 342) freestyle events. Relay performance times for the 2nd-4th swimmers were adjusted (+ 0.73 s) to allow for the "flying start." Without any adjustment, mean individual relay performances were significantly faster for the first 50 m and overall time in the 100-m events. Furthermore, the first 100 m of the 200-m relay was significantly faster (P > .001). During relays, swimmers competing in 1st position did not show any difference compared with their corresponding individual performance (P > .16). However, swimmers competing in 2nd-4th relay-team positions demonstrated significantly faster times in the 100-m (P individual events (P team positions were adjusted for the flying start no differences were detected between relay and individual race performance for any event or split time (P > .17). Highly trained swimmers do not swim (or turn) faster in relay events than in their individual races. Relay exchange times account for the difference observed in individual vs relay performance.

Scalable DeNoise-and-Forward in Bidirectional Relay Networks

DEFF Research Database (Denmark)

Sørensen, Jesper Hemming; Krigslund, Rasmus; Popovski, Petar

2010-01-01

In this paper a scalable relaying scheme is proposed based on an existing concept called DeNoise-and-Forward, DNF. We call it Scalable DNF, S-DNF, and it targets the scenario with multiple communication flows through a single common relay. The idea of the scheme is to combine packets at the relay...... in order to save transmissions. To ensure decodability at the end-nodes, a priori information about the content of the combined packets must be available. This is gathered during the initial transmissions to the relay. The trade-off between decodability and number of necessary transmissions is analysed...

Enabling Critical Reflection on Research Supervisory Practice

Science.gov (United States)

Pearson, Margot; Kayrooz, Carole

2004-01-01

This paper describes the development of an instrument--The Reflective Supervisor Questionnaire (RSQ). The RSQ maps the domain of research supervisory practice as a facilitative process involving educational tasks and activities. It is designed to assist research supervisors explore, by means of self-reflection and reflection on feedback from…

Sleep deprivation influences some but not all processes of supervisory attention

Science.gov (United States)

Jennings, J. R.; Monk, T. H.; van der Molen, M. W.

2003-01-01

Does one night of sleep deprivation alter processes of supervisory attention in general or only a specific subset of such processes? Twenty college-aged volunteers, half female, performed a choice reaction time task. A cue indicated that compatible (e.g., right button, right-pointing arrow) or incompatible (e.g., left button, right-pointing arrow) responses were to be given to a stimulus that followed 50 or 500 ms later. The paradigm assessed response inhibition, task-shifting skill, and task strategy-processes inherent in supervisory attention. Performance, along with heart rate, was assessed for 12 hr following normal sleep or a night of complete sleep deprivation. Sleep deprivation altered neither preparation for task shifting nor response inhibition. The ability to use preparatory bias to speed performance did decrease with sleep deprivation. Sleep deprivation appears to selectively affect this supervisory attention process, which is perceived as an active effort to cope with a challenging task.

Sum-Rate Maximization of Coordinated Direct and Relay Systems

DEFF Research Database (Denmark)

Sun, Fan; Popovski, Petar; Thai, Chan

2012-01-01

Joint processing of multiple communication flows in wireless systems has given rise to a number of novel transmission techniques, notably the two-way relaying based on wireless network coding. Recently, a related set of techniques has emerged, termed coordinated direct and relay (CDR) transmissions......, where the constellation of traffic flows is more general than the two-way. Regardless of the actual traffic flows, in a CDR scheme the relay has a central role in managing the interference and boosting the overall system performance. In this paper we investigate the novel transmission modes, based...... on amplify-and-forward, that arise when the relay is equipped with multiple antennas and can use beamforming. We focus on one representative traffic type, with one uplink and one downlink users and consider the achievable sum-rate maximization relay beamforming. The beamforming criterion leads to a non...

Effects of relay chatter in seismic probabilistic safety analysis

International Nuclear Information System (INIS)

Reed, J.W.; Shiu, K.K.

1985-01-01

In the Zion and Indian Point Probabilistic Safety Studies, relay chatter was dismissed as a credible event and hence was not formally included in the analyses. Although little discussion is given in the Zion and Indian Point PSA documentation concerning the basis for this decision, it has been expressed informally that it was assumed that the operators will be able to reset all relays in a timely manner. Currently, it is the opinion of many professionals that this may be an oversimplification. The three basic areas which must be considered in addressing relay chatter include the fragility of the relays per se, the reliability of the operators to reset the relays and finally the systems response aspects. Each of these areas is reviewed and the implications for seismic PSA are discussed. Finally, recommendations for future research are given

Minimax robust power split in AF relays based on uncertain long-term CSI

KAUST Repository

Nisar, Muhammad Danish

2011-09-01

An optimal power control among source and relay nodes in presence of channel state information (CSI) is vital for an efficient amplify and forward (AF) based cooperative communication system. In this work, we study the optimal power split (power control) between the source and relay node in presence of an uncertainty in the CSI. The prime contribution is to solve the problem based on an uncertain long-term knowledge of both the first and second hop CSI (requiring less frequent updates), and under an aggregate network-level power constraint. We employ the minimax optimization methodology to arrive at the minimax robust optimal power split, that offers the best possible guarantee on the end-to-end signal to noise ratio (SNR). The derived closed form analytical expressions admit simple intuitive interpretations and are easy to implement in real-world AF relaying systems. Numerical results confirm the advantages of incorporating the presence of uncertainty into the optimization problem, and demonstrate the usefulness of the proposed minimax robust optimal power split. © 2011 IEEE.

The remote supervisory and controlling experiment system of traditional Chinese medicine production based on Fieldbus

Science.gov (United States)

Zhan, Jinliang; Lu, Pei

2006-11-01

Since the quality of traditional Chinese medicine products are affected by raw material, machining and many other factors, it is difficult for traditional Chinese medicine production process especially the extracting process to ensure the steady and homogeneous quality. At the same time, there exist some quality control blind spots due to lacking on-line quality detection means. But if infrared spectrum analysis technology was used in traditional Chinese medicine production process on the basis of off-line analysis to real-time detect the quality of semi-manufactured goods and to be assisted by advanced automatic control technique, the steady and homogeneous quality can be obtained. It can be seen that the on-line detection of extracting process plays an important role in the development of Chinese patent medicines industry. In this paper, the design and implement of a traditional Chinese medicine extracting process monitoring experiment system which is based on PROFIBUS-DP field bus, OPC, and Internet technology is introduced. The system integrates intelligence node which gathering data, superior sub-system which achieving figure configuration and remote supervisory, during the process of traditional Chinese medicine production, monitors the temperature parameter, pressure parameter, quality parameter etc. And it can be controlled by the remote nodes in the VPN (Visual Private Network). Experiment and application do have proved that the system can reach the anticipation effect fully, and with the merits of operational stability, real-time, reliable, convenient and simple manipulation and so on.

A psychometric approach to supervisory competency assessment

Directory of Open Access Journals (Sweden)

A. Vorster

2003-10-01

Full Text Available The primary purpose of this study was to evaluate the possibility of using a psychometric approach for assessing supervisory competencies relevant to the mining and refining environment. The competency questionnaire was developed using supervisory roles and registered supervisory unit standards from the United Kingdom (UK, as no registered unit standards exist in South Africa. Twenty-four supervisors from three departments (Production, Engineering and Laboratory were evaluated by 125 raters; besides by themselves, also by their managers, peers, customers and their sub-ordinates. Based on difference scores derived from the Importance and Performance scales, a single factor was extracted with an internal reliability of 0,965. No statistical significant differences were obtained (ANOVA’s, t-test and F-statistics between groups based on biographical variables or between rater groups. The findings and their implications are further discussed. Opsomming Die primêre doel van die studie was om die moontlikheid vir die gebruik van ’n psigometriese benadering tot toesighouerbevoegdheidsbeoordeling, te evalueer. Die bevoegdheidsvraelys is ontwikkel deur gebruik te maak van toesighouersrolle en geregistreerde toesighouerseenheidstandaarde van die Verenigde Koningkryk, as gevolg van ‘n gebrek aan bestaande eenheidstandaarde in Suid-Afrika. Vier-en-twintig toesighouers van drie departemente (Produksie, Ingenieurswese en Laboratorium is deur 125 beoordelaars geëvalueer; buiten deur hulself, ook deur hul bestuurders, kollegas, kliënte en hul ondergeskiktes. ’n Enkele faktor, met ’n betroubaarheid van 0,965, gebaseer op die verskiltellings van die Prestasie- en Belangrikheidskaal, is onttrek. Geen beduidende verskille (ANOVA’s, t-toetse en F-statistiek kon tussen groepe gebaseer op biografiese veranderlikes en die onderskeie beoordelaarsgroepe gevind word nie. Hierdie bevindinge en die implikasies daarvan word verder bespreek.

Relay communications strategies for Mars exploration through 2020

Science.gov (United States)

Edwards, Charles D., Jr.; Arnold, B.; DePaula, R.; Kazz, G.; Lee, C.; Noreen, G.

2005-01-01

In this paper we will examine NASA's strategy for relay communications support of missions planned for this decade, and discuss options for longer-term relay network evolution in support of second-decade missions.

76 FR 65965 - Contributions to the Telecommunications Relay Services Fund

Science.gov (United States)

2011-10-25

...] Contributions to the Telecommunications Relay Services Fund AGENCY: Federal Communications Commission. ACTION... Telecommunications Relay Services (TRS) Fund in a manner prescribed by regulation that is consistent with and... . SUPPLEMENTARY INFORMATION: This is a summary of the Commission's Contributions to the Telecommunications Relay...

Switched diversity strategies for dual-hop relaying systems

KAUST Repository

Gaaloul, Fakhreddine; Alouini, Mohamed-Slim; Radaydeh, Redha M.

2011-01-01

This paper investigates the effect of different switched diversity configurations on the implementation complexity and achieved performance of dual-hop amplify-and-forward (AF) relaying networks. A low-complexity model of the relay station

Reforms to the European Union Financial Supervisory and Regulatory Architecture and Their Implications for Asia

NARCIS (Netherlands)

Z. Darvas (Zsolt); D. Schoenmaker (Dirk); N. Véron (Nicolas)

2017-01-01

textabstractEuropean Union (EU) countries offer a unique experience of financial regulatory and supervisory integration, complementing various other European integration efforts following the Second World War. Financial regulatory and supervisory integration was a very slow process before 2008,

Relay selection in underlay cognitive networks with fixed transmission power nodes

KAUST Repository

Hussain, Syed Imtiaz

2013-07-31

Underlay cognitive networks operate simultaneously with primary networks satisfying stringent interference constraints, which reduces their transmission power and coverage area. To reach remote destinations, secondary sources use relaying techniques. Selecting the best relay among the available ones is a well known technique. Recently, selective cooperation is investigated in cognitive networks where the secondary nodes can adapt their transmission power to always satisfy the interference threshold. In this paper, we investigate a situation where the secondary nodes have a fixed transmission power and may violate the interference threshold. We present two relay selection schemes; the first one excludes the relays not satisfying the interference constraint and then picks up a relay from the remaining ones that can provide the maximum signal-to-noise ratio (SNR). The other scheme uses a quotient of the relay link SNR and the interference from the relay to the primary user and optimizes it to maximise the relay link SNR. We derive closed form expressions for outage probability, bit error rate, channel capacity and diversity of the system for both schemes by using tight approximations. We also study mutual effects of interference. Simulation results confirm the analytical results and reveal that the relay selection is feasible at low SNRs. Copyright © 2013 John Wiley & Sons, Ltd.

Bilayer Protograph Codes for Half-Duplex Relay Channels

Science.gov (United States)

Divsalar, Dariush; VanNguyen, Thuy; Nosratinia, Aria

2013-01-01

Direct to Earth return links are limited by the size and power of lander devices. A standard alternative is provided by a two-hops return link: a proximity link (from lander to orbiter relay) and a deep-space link (from orbiter relay to Earth). Although direct to Earth return links are limited by the size and power of lander devices, using an additional link and a proposed coding for relay channels, one can obtain a more reliable signal. Although significant progress has been made in the relay coding problem, existing codes must be painstakingly optimized to match to a single set of channel conditions, many of them do not offer easy encoding, and most of them do not have structured design. A high-performing LDPC (low-density parity-check) code for the relay channel addresses simultaneously two important issues: a code structure that allows low encoding complexity, and a flexible rate-compatible code that allows matching to various channel conditions. Most of the previous high-performance LDPC codes for the relay channel are tightly optimized for a given channel quality, and are not easily adapted without extensive re-optimization for various channel conditions. This code for the relay channel combines structured design and easy encoding with rate compatibility to allow adaptation to the three links involved in the relay channel, and furthermore offers very good performance. The proposed code is constructed by synthesizing a bilayer structure with a pro to graph. In addition to the contribution to relay encoding, an improved family of protograph codes was produced for the point-to-point AWGN (additive white Gaussian noise) channel whose high-rate members enjoy thresholds that are within 0.07 dB of capacity. These LDPC relay codes address three important issues in an integrative manner: low encoding complexity, modular structure allowing for easy design, and rate compatibility so that the code can be easily matched to a variety of channel conditions without extensive

NRC Information Notice No. 92-27: Thermally induced accelerated aging and failure of ITE/Gould a.c. relays used in safety-related applications

International Nuclear Information System (INIS)

Rossi, C.E.

1993-01-01

On November 23, 1991, while performing an eighteen month engineered safety features operability test, the licensee for the Millstone Nuclear Power Station, Unit 3, noted that control power was interrupted to three safety-related motor operated valves (MOVs). The valves were located in the charging, component cooling water, and steam generator atmospheric dump systems. The licensee inspected the valves' control power circuitry and determined that three normally energized auxiliary relays had failed. These relays provided control power alarms and thermal overload protection for the MOVs. The relay failures rendered each valve inoperable. The relays, which had been in service for about seven years, were class J10 relays with J20M magnet block assemblies and standard G10JA126, 120V, 60 cycle coil assemblies manufactured by the ITE/Gould Manufacturing Company. Inspection of the relays revealed that the movable plastic armature carrier, which surrounds the core and coil, and the retainer for the magnet yoke assembly were discolored, brittle and severely cracked. Insulation degradation was severe, allowing electrical shorts to develop within the coils. The licensee concluded that the failures resulted from the thermal aging of the coil assemblies and plastic parts near the coil assemblies

Implementation of a Relay Coordination System for the Mars Network

Science.gov (United States)

Allard, Daniel A.

2010-01-01

Mars network relay operations involve the coordination of lander and orbiter teams through long-term and short-term planning, tactical changes and post-pass analysis. Much of this coordination is managed through email traffic and point-to-point file data exchanges. It is often difficult to construct a complete and accurate picture of the relay situation at any given moment, as there is no centralized store of correlated relay data. The Mars Relay Operations Service (MaROS) is being implemented to address the problem of relay coordination for current and next-generation relay missions. The service is provided for the purpose of coordinating communications sessions between landed spacecraft assets and orbiting spacecraft assets at Mars. The service centralizes a set of functions previously distributed across multiple spacecraft operations teams, and as such greatly improves visibility into the end-to-end strategic coordination process. Most of the process revolves around the scheduling of communications sessions between the spacecraft during periods of time when a landed asset on Mars is geometrically visible by an orbiting spacecraft. These "relay" sessions are used to transfer data both to and from the landed asset via the orbiting asset on behalf of Earth-based spacecraft operators. This paper will discuss the relay coordination problem space, overview the architecture and design selected to meet system requirements, and describe the first phase of system implementation

Relay-based information broadcast in complex networks

Science.gov (United States)

Fan, Zhongyan; Han, Zeyu; Tang, Wallace K. S.; Lin, Dong

2018-04-01

Information broadcast (IB) is a critical process in complex network, usually accomplished by flooding mechanism. Although flooding is simple and no prior topological information is required, it consumes a lot of transmission overhead. Another extreme is the tree-based broadcast (TB), for which information is disseminated via a spanning tree. It achieves the minimal transmission overhead but the maintenance of spanning tree for every node is an obvious obstacle for implementation. Motivated by the success of scale-free network models for real-world networks, in this paper, we investigate the issues in IB by considering an alternative solution in-between these two extremes. A novel relay-based broadcast (RB) mechanism is proposed by employing a subset of nodes as relays. Information is firstly forwarded to one of these relays and then re-disseminated to others through the spanning tree whose root is the relay. This mechanism provides a trade-off solution between flooding and TB. On one hand, it saves up a lot of transmission overhead as compared to flooding; on the other hand, it costs much less resource for maintenance than TB as only a few spanning trees are needed. Based on two major criteria, namely the transmission overhead and the convergence time, the effectiveness of RB is confirmed. The impacts of relay assignment and network structures on performance are also studied in this work.

Involvement of experts in nuclear licensing and supervisory procedures who are known for their critical attitude towards nuclear technology

International Nuclear Information System (INIS)

Schirp, W.

1996-01-01

The article discusses legal and procedural aspects in the context of expert opinions demanded by the supervisory and licensing authorities of nuclear power plants, and the role and activities of experts known for their critical approach to nuclear electricity generation. The aspects addressed are: Reasons to break the dominance of ''established'' experts who in general are members of the TUeV organisations (technical control boards), reasons for challenging motions such as suspicion of prejudice or insufficient expertise, order by the supervisory authority to take a ''dual approach'' and involve two experts for a task, as well as the relevant administrative and legal procedures. (orig./CB) [de

Cooperative relay-based multicasting for energy and delay minimization

KAUST Repository

Atat, Rachad

2012-08-01

Relay-based multicasting for the purpose of cooperative content distribution is studied. Optimized relay selection is performed with the objective of minimizing the energy consumption or the content distribution delay within a cluster of cooperating mobiles. Two schemes are investigated. The first consists of the BS sending the data only to the relay, and the second scheme considers the scenario of threshold-based multicasting by the BS, where a relay is selected to transmit the data to the mobiles that were not able to receive the multicast data. Both schemes show significant superiority compared to the non-cooperative scenarios, in terms of energy consumption and delay reduction. © 2012 IEEE.

A Quality-Aware Relay Node Placement Algorithm to Connect Disjoint WSN Segments with Topology Reorganized

Directory of Open Access Journals (Sweden)

Zheng Zimu

2014-05-01

Full Text Available Connecting numerous separate parts can be indispensable to simply WSNs that operate autonomously or partitions of a single segmented WSN. Linking them is subject to different intersegment quality of communication and service (QoC and QoS while relay nodes are deployed with their exact number and positions left to define, which is the problem that we focus on. Finding the optimal number and position of relays is NP-hard and therefore heuristics and approximation are pursued. This paper presents an effective approach to deploy appropriate relays to satisfy both the QoC and QoS requirements by introducing probabilistic topology control. The key idea is to regulate a new parallel rule and cost function for segments, which eventually maximizes the utilization of deployed node and avoids the deployment of additional relays as much as possible. The optimization problem is then mapped to finding the path that fulfills the both requirements together with least overheads. The experimental result is validated that although the number of relays is slightly increased to meet extra requirements, the network connectivity can be improved by up to 289.5 % with reorganized topology.

Secure relay selection based on learning with negative externality in wireless networks

Science.gov (United States)

Zhao, Caidan; Xiao, Liang; Kang, Shan; Chen, Guiquan; Li, Yunzhou; Huang, Lianfen

2013-12-01

In this paper, we formulate relay selection into a Chinese restaurant game. A secure relay selection strategy is proposed for a wireless network, where multiple source nodes send messages to their destination nodes via several relay nodes, which have different processing and transmission capabilities as well as security properties. The relay selection utilizes a learning-based algorithm for the source nodes to reach their best responses in the Chinese restaurant game. In particular, the relay selection takes into account the negative externality of relay sharing among the source nodes, which learn the capabilities and security properties of relay nodes according to the current signals and the signal history. Simulation results show that this strategy improves the user utility and the overall security performance in wireless networks. In addition, the relay strategy is robust against the signal errors and deviations of some user from the desired actions.

Proof-of-Work as Anonymous Micropayment: Rewarding a Tor Relay

OpenAIRE

Biryukov, Alex; Pustogarov, Ivan

2015-01-01

In this paper we propose a new micropayments scheme which can be used to reward Tor relay operators. Tor clients do not pay Tor relays with electronic cash directly but submit proof of work shares which the relays can resubmit to a crypto-currency mining pool. Relays credit users who submit shares with tickets that can later be used to purchase improved service. Both shares and tickets when sent over Tor circuits are anonymous. The analysis of the crypto-currencies market prices shows that th...

Error-rate performance analysis of opportunistic regenerative relaying

KAUST Repository

Tourki, Kamel

2011-09-01

In this paper, we investigate an opportunistic relaying scheme where the selected relay assists the source-destination (direct) communication. In our study, we consider a regenerative opportunistic relaying scheme in which the direct path can be considered unusable, and takes into account the effect of the possible erroneously detected and transmitted data at the best relay. We first derive the exact statistics of each hop, in terms of probability density function (PDF). Then, the PDFs are used to determine accurate closed form expressions for end-to-end bit-error rate (BER) of binary phase-shift keying (BPSK) modulation where the detector may use maximum ration combining (MRC) or selection combining (SC). Finally, we validate our analysis by showing that performance simulation results coincide with our analytical results over linear network (LN) architecture and considering Rayleigh fading channels. © 2011 IEEE.

An RSS based location estimation technique for cognitive relay networks

KAUST Repository

Qaraqe, Khalid A.

2010-11-01

In this paper, a received signal strength (RSS) based location estimation method is proposed for a cooperative wireless relay network where the relay is a cognitive radio. We propose a method for the considered cognitive relay network to determine the location of the source using the direct and the relayed signal at the destination. We derive the Cramer-Rao lower bound (CRLB) expressions separately for x and y coordinates of the location estimate. We analyze the effects of cognitive behaviour of the relay on the performance of the proposed method. We also discuss and quantify the reliability of the location estimate using the proposed technique if the source is not stationary. The overall performance of the proposed method is presented through simulations. ©2010 IEEE.

CERN’s annual relay a runaway success

CERN Document Server

Klaus Hanke for the CERN Running Club

2016-01-01

With a record participation of 128 teams of six runners each, this year’s CERN Relay Race took place on 19 May on the Meyrin site.   One of the many winning teams from the 2016 relay race. (Image: Sophia Bennett/CERN) With a record participation of 128 teams and 768 runners, this year’s CERN Relay Race took place on 19 May on the Meyrin site. The teams were mainly composed of CERN staff or contractors working on the CERN site.  A few external teams took also part in the race. Times ranged from 10 min 19 s to over 18 min. The Running Club website now has both the results, and the photos from race day. The CERN Relay Race is jointly organised every year by the CERN Running Club and the Staff Association. It is a tradition that is appreciated by many as a team building, rather than a competitive event. The CERN Running Club wishes to thank all runners and all volunteers for making this event a success.

Efficient incremental relaying for packet transmission over fading channels

KAUST Repository

Fareed, Muhammad Mehboob

2014-07-01

In this paper, we propose a novel relaying scheme for packet transmission over fading channels, which improves the spectral efficiency of cooperative diversity systems by utilizing limited feedback from the destination. Our scheme capitalizes on the fact that relaying is only required when direct transmission suffers deep fading. We calculate the packet error rate for the proposed efficient incremental relaying (EIR) scheme with both amplify and forward and decode and forward relaying. We compare the performance of the EIR scheme with the threshold-based incremental relaying (TIR) scheme. It is shown that the efficiency of the TIR scheme is better for lower values of the threshold. However, the efficiency of the TIR scheme for higher values of threshold is outperformed by the EIR. In addition, three new threshold-based adaptive EIR are devised to further improve the efficiency of the EIR scheme. We calculate the packet error rate and the efficiency of these new schemes to provide the analytical insight. © 2014 IEEE.

Relay discovery and selection for large-scale P2P streaming.

Directory of Open Access Journals (Sweden)

Chengwei Zhang

Full Text Available In peer-to-peer networks, application relays have been commonly used to provide various networking services. The service performance often improves significantly if a relay is selected appropriately based on its network location. In this paper, we studied the location-aware relay discovery and selection problem for large-scale P2P streaming networks. In these large-scale and dynamic overlays, it incurs significant communication and computation cost to discover a sufficiently large relay candidate set and further to select one relay with good performance. The network location can be measured directly or indirectly with the tradeoffs between timeliness, overhead and accuracy. Based on a measurement study and the associated error analysis, we demonstrate that indirect measurements, such as King and Internet Coordinate Systems (ICS, can only achieve a coarse estimation of peers' network location and those methods based on pure indirect measurements cannot lead to a good relay selection. We also demonstrate that there exists significant error amplification of the commonly used "best-out-of-K" selection methodology using three RTT data sets publicly available. We propose a two-phase approach to achieve efficient relay discovery and accurate relay selection. Indirect measurements are used to narrow down a small number of high-quality relay candidates and the final relay selection is refined based on direct probing. This two-phase approach enjoys an efficient implementation using the Distributed-Hash-Table (DHT. When the DHT is constructed, the node keys carry the location information and they are generated scalably using indirect measurements, such as the ICS coordinates. The relay discovery is achieved efficiently utilizing the DHT-based search. We evaluated various aspects of this DHT-based approach, including the DHT indexing procedure, key generation under peer churn and message costs.

A Double-Deck Elevator Group Supervisory Control System with Destination Floor Guidance System Using Genetic Network Programming

Science.gov (United States)

Yu, Lu; Zhou, Jin; Mabu, Shingo; Hirasawa, Kotaro; Hu, Jinglu; Markon, Sandor

The Elevator Group Supervisory Control Systems (EGSCS) are the control systems that systematically manage three or more elevators in order to efficiently transport the passengers in buildings. Double-deck elevators, where two elevators are connected with each other, serve passengers at two consecutive floors simultaneously. Double-deck Elevator systems (DDES) become more complex in their behavior than conventional single-deck elevator systems (SDES). Recently, Artificial Intelligence (AI) technology has been used in such complex systems. Genetic Network Programming (GNP), a graph-based evolutionary method, has been applied to EGSCS and its advantages are shown in some papers. GNP can obtain the strategy of a new hall call assignment to the optimal elevator when it performs crossover and mutation operations to judgment nodes and processing nodes. Meanwhile, Destination Floor Guidance System (DFGS) is installed in DDES, so that passengers can also input their destinations at elevator halls. In this paper, we have applied GNP to DDES and compared DFGS with normal systems. The waiting time and traveling time of DFGS are all improved because of getting more information from DFGS. The simulations showed the effectiveness of the double-deck elevators with DFGS in different building traffics.

Optimal Coordination of Distance and Directional Overcurrent Relays Considering Different Network Topologies

OpenAIRE

Y. Damchi; J. Sadeh; H. Rajabi Mashhadi

2015-01-01

Most studies in relay coordination have focused solely on coordination of overcurrent relays while distance relays are used as the main protection of transmission lines. Since, simultaneous coordination of these two types of relays can provide a better protection, in this paper, a new approach is proposed for simultaneous coordination of distance and directional overcurrent relays (D&DOCRs). Also, pursued by most of the previously published studies, the settings of D&DOCRs are usually determi...

Coordination of Regenerative Relays and Direct Users in Wireless Cellular Networks

DEFF Research Database (Denmark)

Thai, Chan; Popovski, Petar

2011-01-01

The area of wireless cooperation/relaying has recently been significantly enriched by the ideas of wireless network coding (NC), which bring substantial gains in spectral efficiency. These gains have mainly been demonstrated in scenarios with two-way relaying. Inspired by the ideas of wireless NC......, recently we have proposed techniques for coordinated direct/relay (CDR) transmissions. These techniques embrace the interference among the communication flows to/from direct and relayed users, leveraging on the fact that the interference can be subsequently canceled. Hence, by allowing simultaneous...... transmissions, spectral efficiency is increased. In our prior work, we have considered CDR with non-regenerative relay that uses Amplify-and-Forward (AF). In this paper we consider the case of regenerative Decode-and-Forward (DF) relay. This refers also to joint decoding of the interfering flows received over...

Development and Control of a Three-Axis Satellite Simulator for the Bifocal Relay Mirror Initiative

National Research Council Canada - National Science Library

Chernesky, Vincent

2001-01-01

.... The bifocal relay mirror spacecraft system is composed of two optically coupled telescopes used to redirect the laser light from ground-based, aircraft-based or spacecraft based lasers to distant...

Implementation of a microcomputer based distance relay for parallel transmission lines

International Nuclear Information System (INIS)

Phadke, A.G.; Jihuang, L.

1986-01-01

Distance relaying for parallel transmission lines is a difficult application problem with conventional phase and ground distance relays. It is known that for cross-country faults involving dissimilar phases and ground, three phase tripping may result. This paper summarizes a newly developed microcomputer based relay which is capable of classifying the cross-country fault correctly. The paper describes the principle of operation and results of laboratory tests of this relay

Performance Analysis of Selective Decode-and-Forward Multinode Incremental Relaying with Maximal Ratio Combining

KAUST Repository

Hadjtaieb, Amir

2013-09-12

In this paper, we propose an incremental multinode relaying protocol with arbitrary N-relay nodes that allows an efficient use of the channel spectrum. The destination combines the received signals from the source and the relays using maximal ratio Combining (MRC). The transmission ends successfully once the accumulated signal-to-noise ratio (SNR) exceeds a predefined threshold. The number of relays participating in the transmission is adapted to the channel conditions based on the feedback from the destination. The use of incremental relaying allows obtaining a higher spectral efficiency. Moreover, the symbol error probability (SEP) performance is enhanced by using MRC at the relays. The use of MRC at the relays implies that each relay overhears the signals from the source and all previous relays and combines them using MRC. The proposed protocol differs from most of existing relaying protocol by the fact that it combines both incremental relaying and MRC at the relays for a multinode topology. Our analyses for a decode-and-forward mode show that: (i) compared to existing multinode relaying schemes, the proposed scheme can essentially achieve the same SEP performance but with less average number of time slots, (ii) compared to schemes without MRC at the relays, the proposed scheme can approximately achieve a 3 dB gain.

Spectral efficiency enhancement with interference cancellation for wireless relay network

DEFF Research Database (Denmark)

Yomo, Hiroyuki; De Carvalho, Elisabeth

The introduction of relaying into wireless communication system for coverage enhancement can cause severe decrease of spectral efficiency due to the requirement on extra radio resource. In this paper, we propose a method to increase spectral efficiency in such a wireless relay network by employing...... an interference cancellation technique. We focus on a typical scenario of relaying in a cellular system, where a mobile station (MS) requires the help of a relay station (RS) to communicate with the base station (BS). In such a case, interference cancellation can be used to achieve a small reuse distance...... of identical radio resource. We analyze a simple scenario with BS, single RS, and 2 MSs, and show that the proposed method has significant potential to enhance spectral efficiency in wireless relay networks....

Resource allocation for relay assisted cognitive radio networks

KAUST Repository

Zafar, Ammar; Alouini, Mohamed-Slim; Chen, Yunfei; Radaydeh, Redha M.

2012-01-01

transmission power and the relay transmission power. Numerical results show that the optimal sensing time is dependent on the primary user's signal-to-noise-ratio (SNR). They also show that SCR increases with increase in the number of relays. © 2012 IEEE.

Protective relaying of power systems using mathematical morphology

CERN Document Server

Wu, QH; Ji, TY

2009-01-01

Discusses the development of novel protective relaying algorithms, using Mathematical Morphology (MM). This book introduces the fundamental principles of MM, and brings together the applications of MM to develop different protective relaying algorithms for the protection of a variety of power system components.

Novel Material Integration for Reliable and Energy-Efficient NEM Relay Technology

Science.gov (United States)

Chen, I.-Ru

Energy-efficient switching devices have become ever more important with the emergence of ubiquitous computing. NEM relays are promising to complement CMOS transistors as circuit building blocks for future ultra-low-power information processing, and as such have recently attracted significant attention from the semiconductor industry and researchers. Relay technology potentially can overcome the energy efficiency limit for conventional CMOS technology due to several key characteristics, including zero OFF-state leakage, abrupt switching behavior, and potentially very low active energy consumption. However, two key issues must be addressed for relay technology to reach its full potential: surface oxide formation at the contacting surfaces leading to increased ON-state resistance after switching, and high switching voltages due to strain gradient present within the relay structure. This dissertation advances NEM relay technology by investigating solutions to both of these pressing issues. Ruthenium, whose native oxide is conductive, is proposed as the contacting material to improve relay ON-state resistance stability. Ruthenium-contact relays are fabricated after overcoming several process integration challenges, and show superior ON-state resistance stability in electrical measurements and extended device lifetime. The relay structural film is optimized via stress matching among all layers within the structure, to provide lower strain gradient (below 10E-3/microm -1) and hence lower switching voltage. These advancements in relay technology, along with the integration of a metallic interconnect layer, enable complex relay-based circuit demonstration. In addition to the experimental efforts, this dissertation theoretically analyzes the energy efficiency limit of a NEM switch, which is generally believed to be limited by the surface adhesion energy. New compact (electronic device technology.

strategies for improving supervisory skills for effective primary ...

African Journals Online (AJOL)

Elizabeth

certain basic concepts such as inspection and supervision, the responsibility of supervisors, relevant areas in ... Strategies For Improving Supervisory Skills For Effective Primary Education In Nigeria. Enaigbe A. P. 236 ... book, attendance book etc. 6) Managerial Skills: These are skills on time management, good use.

A Stochastic Geometry Approach to Full-Duplex MIMO Relay Network

Directory of Open Access Journals (Sweden)

Mhd Nour Hindia

2018-01-01

Full Text Available Cellular networks are extensively modeled by placing the base stations on a grid, with relays and destinations being placed deterministically. These networks are idealized for not considering the interferences when evaluating the coverage/outage and capacity. Realistic models that can overcome such limitation are desirable. Specifically, in a cellular downlink environment, the full-duplex (FD relaying and destination are prone to interferences from unintended sources and relays. However, this paper considered two-hop cellular network in which the mobile nodes aid the sources by relaying the signal to the dead zone. Further, we model the locations of the sources, relays, and destination nodes as a point process on the plane and analyze the performance of two different hops in the downlink. Then, we obtain the success probability and the ergodic capacity of the two-hop MIMO relay scheme, accounting for the interference from all other adjacent cells. We deploy stochastic geometry and point process theory to rigorously analyze the two-hop scheme with/without interference cancellation. These attained expressions are amenable to numerical evaluation and are corroborated by simulation results.

Minimax robust relay selection based on uncertain long-term CSI

KAUST Repository

Nisar, Muhammad Danish

2014-02-01

Cooperative communications via multiple relay nodes is known to provide the benefits of increase diversity and coverage. Simultaneous transmission via multiple relays, however, requires strong coordination between nodes either in terms of slot-based transmission or distributed space-time (ST) code implementation. Dynamically selecting a single best relay out of multiple relays and then using it alone for cooperative transmission alleviates the need for this strong coordination while still reaping the benefits of increased diversity and coverage. In this paper, we consider the design of relay selection (RS) under an imperfect knowledge of long-term channel state information (CSI) at the relay nodes, and we pursue minimax optimization to arrive at a robust RS approach that promises the best guarantee on the worst-case end-to-end signal-to-noise ratio (SNR). We provide some intuitive examples and extensive simulation results, not only in terms of worst-case SNR performance but also in terms of average bit-error-rate (BER) performance, to demonstrate the benefits of the proposed minimax robust RS scheme. © 2013 IEEE.

The Relationship between Supervisee Stress, Coping Resources, the Working Alliance, and the Supervisory Working Alliance

Science.gov (United States)

Gnilka, Philip B.; Chang, Catherine Y.; Dew, Brian J.

2012-01-01

The authors examined the relationship of perceived stress, specific types of coping resources, the working alliance, and the supervisory working alliance among 232 counselor supervisees. The working alliance and the supervisory working alliance were negatively related to perceived stress and positively related to multiple coping resources. Two…

Quasi-period oscillations of relay feedback systems

International Nuclear Information System (INIS)

Wen Guilin; Wang Qingguo; Lee, T.H.

2007-01-01

This paper presents an analytical method for investigation of the existence and stability of quasi-period oscillations (torus solutions) for a class of relay feedback systems. The idea is to analyze Poincare map from one switching surface to the next based on the Hopf bifurcation theory of maps. It is shown that there exist quasi-period oscillations in certain relay feedback systems

Development of a supervisory skills course for hospital pharmacy workplaces.

Science.gov (United States)

Woloschuk, Donna M M; Raymond, Colette B

2010-07-01

Many Canadian hospital pharmacies are experiencing difficulties recruiting supervisory personnel. It was expected that, through a "learning-by-doing" course, pharmacy staff would learn to apply basic skills in the day-to-day supervision of pharmacy operations and human resources and to apply the principles of supervisory documentation. A supervisory skills course targeted to pharmacy staff members was developed and implemented by the pharmacy department of a large urban health region. The course was initially offered to practising pharmacy technicians. The course design emphasized a constructivist framework incorporating authentic learning and reflective practice during seminars, with experiential and self-directed learning in the workplace. Preceptors assisted learners to achieve the course goals. Learners and preceptors provided feedback about hours spent (as the course progressed) and about their satisfaction with the course itself (at the end of the course). Learners and preceptors completed a post-program evaluation 2 months after completing the course to help in the assessment of the transfer of learning (lasting impact) associated with the course. Overall performance in the course was assessed on a pass/fail basis. Eighteen pharmacy technicians were admitted to the program, but one withdrew because of a job change. All learners successfully completed the course. Two months after the course, learners and preceptors described enhanced organization, time management, leadership, communication, and conflict-resolution skills on the part of learners, as well as their increased confidence, maturity, and ability to supervise staff. Learners' evaluations revealed a broadened perspective of pharmacy. The preceptors valued the enhancement of learners' skills and their increased enthusiasm. At the time of writing, 6 of the participants had secured supervisory positions. Creating formal instruction that engages pharmacy staff to pursue management positions is challenging

Interference alignment for degrees of freedom improvement in 3-relay half-duplex systems

KAUST Repository

Park, Seongho

2011-12-01

In a half-duplex relaying, the capacity pre-log factor is a major drawback in spectral efficiency. This paper proposes a linear precoding scheme and an alternate relaying protocol in a dual-hop half-duplex system where three relays help the communication between the source and the destination. In our proposed scheme, we consider a phase incoherent method in relays in which the source alternately transmits message signals to the different relays. In addition, we propose a linear interference alignment scheme which can eliminate the inter-relay interference resulted from the phase incoherence of relaying. Based on our analysis of degrees of freedom and our simulation results, we show that our proposed scheme achieves additional degrees of freedom compared to the conventional half-duplex relaying. © 2011 IEEE.

Overlay cognitive radio systems with adaptive two-way relaying

KAUST Repository

Hyadi, Amal

2013-12-01

In this paper, we propose a spectrum sharing mechanism with a two-phase two-way relaying protocol for an overlay cognitive network. The system comprises two primary users (PUs) and two secondary users (SUs). One of the SUs acts as a relay for the PUs and gains spectrum sharing as long as he respects outage probability constraints of the primary system. Moreover, we consider that the relaying node performs an optimal power allocation scheme that minimizes the outage performance of the secondary receiver. Closed form expressions for the outage probability are derived for the cases of Decode-and-Forward (DF), Amplify-and-Forward (AF), and adaptive relaying. Numerical simulations are presented to illustrate and compare the obtained results. © 2013 IEEE.

Building Supervisory Confidence--A Key to Transfer of Training

Science.gov (United States)

Byham, William C.; Robinson, James

1977-01-01

A training concept is described which suggests that efforts toward maintaining and/or building the confidence of the participants in supervisory training programs can increase their likelihood of using the skills on the job. (TA)

Independence and executive remuneration for supervisory board members and non-executive directors

Directory of Open Access Journals (Sweden)

Hana Horak

2011-01-01

Full Text Available In this paper, the author analyses the issues of independence and rewarding members of supervisory boards and non-executive directors in administrative boards. The question of independence was developed as one of the fundamental issues of corporative administration. Members of these organs of society should have the appropriate qualifications, specific knowledge and skills in order to reasonably and impartially weigh up social business and reach decisions in the best interests of society, its members and other interest holders. So that they can act in accordance with this, the presumption is that they are independent. Recently, after financial crises, it is precisely the independence of supervisory members, that is, non-executive directors, which is considered to be the foundation of the fight against the opportunism of administration and main shareholders. The authors analyse the Recommendations on Independence and Executive Remuneration for members of supervisory and administrative boards of the European Union, together with their implementation in Croatian law and practice.

Best relay selection using SNR and interference quotient for underlay cognitive networks

KAUST Repository

Hussain, Syed Imtiaz

2012-06-01

Cognitive networks in underlay settings operate simultaneously with the primary networks satisfying stringent interference limits. This condition forces them to operate with low transmission powers and confines their area of coverage. In an effort to reach remote destinations, underlay cognitive sources make use of relaying techniques. Selecting the best relay among those who are ready to cooperate is different in underlay settings than traditional non-cognitive networks. In this paper, we present a relay selection scheme which uses the quotient of the relay link signal to noise ratio (SNR) and the interference generated from the relay to the primary user to choose the best relay. The proposed scheme optimizes this quotient in a way to maximize the relay link SNR above a certain value whereas the interference is kept below a defined threshold. We derive closed expressions for the outage probability and bit error probability of the system incorporating this scheme. Simulation results confirm the validity of the analytical results and reveal that the relay selection in cognitive environment is feasible in low SNR regions. © 2012 IEEE.

Adaptive transmission based on multi-relay selection and rate-compatible LDPC codes

Science.gov (United States)

Su, Hualing; He, Yucheng; Zhou, Lin

2017-08-01

In order to adapt to the dynamical changeable channel condition and improve the transmissive reliability of the system, a cooperation system of rate-compatible low density parity check (RC-LDPC) codes combining with multi-relay selection protocol is proposed. In traditional relay selection protocol, only the channel state information (CSI) of source-relay and the CSI of relay-destination has been considered. The multi-relay selection protocol proposed by this paper takes the CSI between relays into extra account in order to obtain more chances of collabration. Additionally, the idea of hybrid automatic request retransmission (HARQ) and rate-compatible are introduced. Simulation results show that the transmissive reliability of the system can be significantly improved by the proposed protocol.

Comparative study of researcher community support and supervisory support among Finnish and Danish PhD-students

DEFF Research Database (Denmark)

Cornér, Solveig; Pyhältö, Kirsi; Peltonen, Jouni

Prior research on doctoral supervision and researcher communities has identified social support as a key determinant of the doctoral journey (Jairam & Kahl, 2012; Zhao, Golde & McCormick, 2007). Supervisory support, for instance, in terms of constructive feedback and encouragement (Pyhältö......, 313-329. • Pyhältö, K., Vekkaila (o.s. Tuomainen), J., & Keskinen, J. (2015). Fit matters in the supervisory relationship: Doctoral students’ and supervisors’ perceptions about supervisory activities. Innovations in Education and Teaching International, 52(1), 4-16. • Zhau, C-M, Golde, C.M., McCormick...

A Tool For Enhancing Supervisory Effectiveness In Nigerian ...

African Journals Online (AJOL)

This paper examined the relevance of Information and Communication Technology (ICT) as a tool for enhancing supervisory effectiveness in Nigerian educational institutions. The paper highlighted various tools of ICT that could be used in educational supervision such as Closed Circuit Television (CCTV) Cameras, e-mails ...

Influence of perceived co-worker involvement and supervisory ...

African Journals Online (AJOL)

This study investigated the influence of perceived co-worker involvement and Supervisory Support on Job Satisfaction among Staff of Champion Brewery, Uyo. One hundred and fifty (150) participants were drawn as participant using simple randomization. The participants were ninety five males and fifty five females whose ...

Frame Allocation and Scheduling for Relay Networks in the LTE Advanced Standard

OpenAIRE

Roth, Stefan

2010-01-01

The use of relays is seen as a promising way to extend cell coverage and increase rates in LTE Advanced networks. Instead of increasing the number of base stations (BS), relays with lower cost could provide similar gains. A relay will have a wireless link to the closest BS as only connection to the core network and will cover areas close to the cell edge or other areas with limited rates. Performing transmissions in several hops (BS-relay & relay-user) requires more radio resources than u...

77 FR 16435 - Transmission Relay Loadability Reliability Standard

Science.gov (United States)

2012-03-21

... conditions on all applicable transmission lines and transformers. I. Background A. Relay Protection Systems 2... and a power swing. If a power swing is detected, the protection system, ``blocks,'' or prevents the... to the reliability of the Bulk-Power System by requiring load-responsive phase protection relay...

76 FR 58424 - Transmission Relay Loadability Reliability Standard

Science.gov (United States)

2011-09-21

... distribution providers to set load-responsive phase protection relays according to specific criteria to ensure...-part R.1.10 allows transmission owners, generation owners and distribution providers to set transformer.... Thus, requiring that transformer fault protection relays are set to not expose the transformer to a...

Development of a Relay Performance Web Tool for the Mars Network

Science.gov (United States)

Allard, Daniel A.; Edwards, Charles D.

2009-01-01

Modern Mars surface missions rely upon orbiting spacecraft to relay communications to and from Earth systems. An important component of this multi-mission relay process is the collection of relay performance statistics supporting strategic trend analysis and tactical anomaly identification and tracking.

Micro-relay technology for energy-efficient integrated circuits

CERN Document Server

Kam, Hei

2015-01-01

This book describes the design of relay-based circuit systems from device fabrication to circuit micro-architectures. This book is ideal for both device engineers as well as circuit system designers and highlights the importance of co-design across design hierarchies when optimizing system performance (in this case, energy-efficiency). This book is ideal for researchers and engineers focused on semiconductors, integrated circuits, and energy efficient electronics. This book also: ·         Covers microsystem fabrication, MEMS device design, circuit design, circuit micro-architecture, and CAD ·         Describes work previously done in the field and also lays the groundwork and criteria for future energy-efficient device and system design ·         Maximizes reader insights into the design and modeling of micro-relay, micro-relay reliability, integrated circuit design with micro-relays, and more

Linear Processing Design of Amplify-and-Forward Relays for Maximizing the System Throughput

Directory of Open Access Journals (Sweden)

Qiang Wang

2018-01-01

Full Text Available In this paper, firstly, we study the linear processing of amplify-and-forward (AF relays for the multiple relays multiple users scenario. We regard all relays as one special “relay”, and then the subcarrier pairing, relay selection and channel assignment can be seen as a linear processing of the special “relay”. Under fixed power allocation, the linear processing of AF relays can be regarded as a permutation matrix. Employing the partitioned matrix, we propose an optimal linear processing design for AF relays to find the optimal permutation matrix based on the sorting of the received SNR over the subcarriers from BS to relays and from relays to users, respectively. Then, we prove the optimality of the proposed linear processing scheme. Through the proposed linear processing scheme, we can obtain the optimal subcarrier paring, relay selection and channel assignment under given power allocation in polynomial time. Finally, we propose an iterative algorithm based on the proposed linear processing scheme and Lagrange dual domain method to jointly optimize the joint optimization problem involving the subcarrier paring, relay selection, channel assignment and power allocation. Simulation results illustrate that the proposed algorithm can achieve a perfect performance.

A study on Relay Effect via Magnetic Resonant Coupling for Wireless Power Transfer

Directory of Open Access Journals (Sweden)

Rashid N.A.

2016-01-01

Full Text Available Wireless power transfer (WPT transmits electrical energy from a power source to an electrical load wirelessly or without any conductors. The capability of WPT to transmit the energy is limited. Therefore, a relay was introduced to increase the distance of the WPT capabilities. The effect of the relay has been investigated to extend the energy transfer distance. The effect of relay was demonstrated by placing a relay coil between transmitter and receiver, relay biased to transmitter and placing two relay coils in the designed system. Experimental results are provided to prove the concept of the relay effect. The power transmission efficiency can be achieved up to 75% at 1 meter distance.

Cooperation schemes for rate enhancement in detect-and-forward relay channels

KAUST Repository

Benjillali, Mustapha

2010-05-01

To improve the spectral efficiency of "Detect-and-Forward" (DetF) half-duplex relaying in fading channels, we propose a cooperation scheme where the relay uses a modulation whose order is higher than the one at the source. In a new common framework, we show that the proposed scheme offers considerable gains - in terms of achievable information rates - compared to the conventional DetF relaying schemes for both orthogonal and non-orthogonal source/relay cooperation. This allows us to propose an adaptive cooperation scheme based on the maximization of the information rate at the destination which needs to observe only the average signal-to-noise ratios of direct and relaying links. ©2010 IEEE.

IEEE C37.98-1987: IEEE standard seismic testing of relays

International Nuclear Information System (INIS)

Anon.

1992-01-01

This standard specifies the procedures to be used in the seismic testing of relays used in power system facilities. The standard is concerned with the determination of the seismic fragility level of relays and also gives recommendations for proof testing. The purpose of this standard is to establish procedures for determining the seismic capabilities of protective and auxiliary relays. These procedures employ what has been called fragility testing in IEEE Std 344-1987. To define the conditions for fragility testing of relays, parameters in three separate areas must be specified. In general, they are (1) the electrical settings and inputs to the relay, and other information to define its conditions during the test; (2) the change in state, deviation in operating characteristics or tolerances, or other change of performance of the relay that constitutes failure; (3) the seismic vibration environment to be imposed during the test. Since it is not possible to define the conditions for every conceivable application for all relays, those parameters, which in practice encompass the majority of applications, have been specified in this standard. When the application of the relay is other than as specified under any of (1), (2), and (3), or if it is not practical to apply existing results of fragility tests to that new application, then proof testing must be performed for that new case

IEEE C37.98-1978: IEEE standard seismic testing of relays

International Nuclear Information System (INIS)

Anon.

1992-01-01

This standard specifies the procedures to be used in the seismic testing of relays used in power system facilities. The standard is concerned with the determination of the seismic fragility level of relays and also gives recommendations for proof testing. The purpose of this standard is to establish procedures for determining the seismic capabilities of protective and auxiliary relays. These procedures employ what has been called fragility testing in ANSI/IEEE Std 344-1975, Recommended Practices for Seismic Qualification of Class 1E Equipment for Nuclear Power Generating Stations. In order to define the conditions for fragility testing of relays, parameters in three separate areas must be specified. In general they are: (1) the electrical settings and inputs to the relay, and other information to define its conditions during the test; (2) the change in state, deviation in operating characteristics or tolerances, or other change of performance of the relay which constitutes failure; (3) the seismic vibration environment to be imposed during the test. Since it is not possible to define the conditions for every conceivable application for all relays, those parameters, which in practice encompass the majority of applications, have been specified in this standard. When the application of the relay is other than as specified under any of (1), (2), and (3), or if it is not practical to apply existing results of fragility tests to that new case

Commerce Supervisory Course: Discussion Guide. Theories of Supervision.

Science.gov (United States)

McCaw, Edward A.

The contributions of Frederick W. Taylor, Henri Fayol and Elton Mayo to the development of current concepts of supervisory theory are outlined. Ten newer concepts of management, with graphics, provide the supervisor with an opportunity to formulate his own personal theory. Suggested bibliography for supervisors is given. (Author/NF)

STUDI ANALISIS KOORDINASI OVER CURRENT RELAY (OCR) DAN GROUND FAULT RELAY (GFR) PADA RECLOSER DI SALURAN PENYULANG PENEBEL

OpenAIRE

I Dewa Gde Agung Budhi Udiana; I G Dyana Arjana; Tjok Gede Indra Partha

2017-01-01

Short circuit causing over current problem and can might causing interference of the equipment performance such as distribution transformers also causing widespread disruption occurred. In resolving such interference is required as protection system on the distribution system. Seeing all above is needed coordination between the supporting component of the protection system which is consisted of Over Current Relay (OCR) and Ground Fault Relay (GFR). The research was conducted at PT. PLN (Perse...

On the Outage Performance of Full-Duplex Selective Decode-and-Forward Relaying

KAUST Repository

Khafagy, Mohammad Galal

2013-02-25

We evaluate the outage performance in a three-terminal full-duplex relay channel that adopts a selective decode-and-forward protocol, taking relay self-interference into account. Previous work focused on coverage extension scenarios where direct source-destination transmissions are neglected or considered as interference. In this work, we account for the relay self-interference, and exploit the cooperative diversity offered by the independently fading source/relay message replicas that arrive at the destination. We present an approximate, yet accurate, closed-form expression for the end-to-end outage probability that captures their joint effect. With the derived expression in hand, we propose a relay transmit power optimization scheme that only requires the relay knowledge of channel statistics. Finally, we corroborate our analysis with simulations.

An Optimal Analysis in Wireless Powered Full-duplex Relaying Network

Directory of Open Access Journals (Sweden)

K.-T. Nguyen

2017-04-01

Full Text Available Wireless-powered cellular networks (WPCNs are currently being investigated to exploit the reliability and improve battery lifetime of mobile users. This paper investigates the energy harvesting structure of the full-duplex relaying networks. By using the time switching based relaying (TSR protocol and Amplify-and-Forward (AF model in delay-limited transmission scheme, we propose the closed-form expression of the outage probability and then calculate the optimal throughput. An important result can be taken obviously that the time fraction in TSR, the position of relay, the noise as well as the energy conversation impacting on the outage probability as well as the optimal throughput. By Monte Carlo simulation, the numerical results indicate an effective relaying strategy in full-duplex cooperative systems. Finally, we provide fundamental design guidelines for selecting time fraction in TSR that satisfies the requirements of a practical relaying system.

Toward distributed relay selection for opportunistic amplify-and-forward transmission

KAUST Repository

Tourki, Kamel

2011-05-01

Opportunistic relaying in cooperative communication depends on careful relay selection. However the traditional centralized method used for opportunistic Amplify-and-Forward (OAF) protocols requires precise measurements of channel state information (CSI) at the destination (CSI-OAF). In this paper, we propose a distributed relay selection framework for opportunistic AF (D-OAF) cooperative communications and offer an accurate performance analysis based on exact statistics of the local signalto- noise ratios of the best relay. Furthermore, we validate our analysis by showing that performance simulation results coincide with our analytical results over different network architectures, and we compare our new results with their CSI-based counterparts. © 2011 IEEE.

Democratic Dialogue as a Process to Inform Public Policy: Reconceptualizing a Supervisory Officer’s Qualification Program

Directory of Open Access Journals (Sweden)

Deirdre M. Smith

2015-06-01

Full Text Available An exploration of the collaborative reconceptualization of a provincial Supervisory Officer’s Qualification Program (SOQP through the use of dialogic approaches is the focus of this inquiry. The stories, perspectives, and lived experiences of supervisory officers, principals, teachers, parents, students, and members of the public in Ontario were included as essential voices and information sources within policy development conversations. These narratives of experience revealed the forms of knowledge, skills, dispositions, and ethical commitments necessary for effective supervisory officers today and in the future. They also illustrated the transformative nature of narrative dialogue to enlighten, deepen understanding, and alter perspec- tives. The policy development processes used in this publicly shared educational initiative serve as a model of democratic dialogue. The inclusive and dialogic methods employed to collectively reconceptualize a supervisory officer formation program illustrate an innovative framework for developing policies governing the public good.

The relationship between constructivist supervisory practices, school climate, and student proficiency in reading, mathematics, and science: Evidence from NELS:88

Science.gov (United States)

Molnar, John Alexander

In an effort to improve instruction and student learning, school reform efforts have become prevalent. School reformers have examined many aspects of the school experience, including learning theories such as behaviorism and constructivism, the changing roles of teachers and supervisors, and even the concept of the school itself. The theoretical framework for this study centered around constructivist learning theory. The study itself focused on the application of constructivist learning theory to the supervisory process. The study examined five areas of interest: (a) teachers' perceptions of constructivist supervisory behavior; (b) teachers' perceptions of efficacy and control in the classroom; (c) teachers' perceptions of school climate; (d) teachers' perceptions of job satisfaction, and (e) the influences of each of the aforementioned on student proficiency in mathematics, reading, and science. Data for the study was drawn from the first follow-up survey of the National Educational Longitudinal Study of 1988 (NELS: 88). NELS: 88 investigated a wide variety of factors that influence the educational process. The first follow-up focuses on environmental factors that affect teachers and students. Variables were selected from the NELS:88 data set that represented the areas to be examined. Factor analysis and correlational analysis were applied to ensure that the variables were measuring distinct constructs and to determine ways they could be grouped for analysis. Multiple linear regression analysis was applied to determine relationships among the individual and composite variables, controlling for student and teacher demographic factors. The results of the study suggest that varying relationships do exist between constructivist supervisory practices and the constructs measuring school climate and job satisfaction. The results also suggest that varying relationships exist between each of these factors and student proficiency in mathematics, reading, and science

RTE - Business and sustainable development report 2015. Management report consolidated financial statements 2015. Report by the chairman of the supervisory board 2015

International Nuclear Information System (INIS)

2016-01-01

After an introduction by the RTE's CEO, brief presentations of governance bodies (management board, executive committee, supervisory board), and a presentation of some statistics illustrating RTE activities and efficiency, the activity report addresses and illustrates some specific issues: moving for local to European scale by promoting electrical solidarity among the regions, climate solutions in support of sustainable, economical and efficient power system, experts solutions for tomorrow's electricity. The management report contains financial and legal information (significant events of 2015, economic environment, business and results, financing, financial structure, outlook for 2016, risk analysis), company information (employment, work organisation, labour relations, health and safety, training, diversity and equal opportunities, compliance with International Labour Organisation conventions), environmental information (general environmental policy, pollution and waste management, sustainable use of resources, climate change, protection and development of biodiversity), and societal information (local, economic and social impact of RTE's business, relations with people and organisations concerned by RTE's business, out-sourcing and suppliers, fair practices, other action to promote human rights). The third report presents the governance organisation of RTE (supervisory board, executive board, principles of remuneration of supervisory board and executive board members, general meetings, information publication). It describes the internal control at RTE (organisation, actors), presents the policy of risk management and control, activities of audit and control within RTE. It finally presents external controls made by different public bodies

Use of Behavior and Influence Functions for Relay Selection in Cooperative Communications

DEFF Research Database (Denmark)

Craciunescu, Razvan; Mihovska, Albena Dimitrova; Prasad, Ramjee

2015-01-01

This paper uses a novel set of functions to model the relay selection process in a scenario of cooperative wireless communications. We define a utility function that reflects the behavior and influence that a selected relay may have on the quality of the link to be established for the forwarding...... of data. The utility function takes into account also the strategies of other players. To this end, we define a relay selection game and a supporting Nash Equilibrium (NE) algorithm for the choice of a relay during communication. The successful selection of a relay is evaluated by simulations in terms...

CERN Relay Race

CERN Multimedia

2004-01-01

The CERN Relay Race will take place around the Meyrin site on Wednesday 19 May between 12.15 and 12.35. If possible, please avoid driving on the site during this 20 minute period. If you do meet runners in your car, please STOP until they all have passed. Thank you for your understanding

CERN Relay Race

CERN Multimedia

2001-01-01

The CERN Relay Race will take place around the Meyrin site on Wednesday 23 May between 12:20 and 12:35. If possible, please avoid driving on the site during this 15 minute period. If you do meet runners in your car, please stop until they all have passed. Thank you for your understanding.

Two-way CSI-assisted AF relaying with HPA nonlinearity

KAUST Repository

Qi, Jian; Aissa, Sonia; Alouiniz, Mohamed-Slim

2015-01-01

In this paper, we investigate half-duplex two-way dual-hop channel state information (CSI)-assisted amplify-andforward (AF) relaying in the presence of high-power amplifier (HPA) nonlinearity at relays. The expression for the end-toend signal

CERN Relay Race

CERN Multimedia

Running Club

2010-01-01

This year’s CERN Relay Race will take place around the Meyrin site on Thursday 20th May at 12h00. This annual event is for teams of 6 runners covering distances of 1000m, 800m, 800m, 500m, 500m and 300m respectively. Teams may be entered in the Seniors, Veterans, Ladies, Mixed or Open categories. The registration fee is 10 CHF per runner, and each runner receives a souvenir prize. As usual, there will be a programme of entertainments from 12h in the arrival area, in front of the Restaurant no. 1. Drinks, food, CERN club information and music will be available for the pleasure of both runners and spectators. The race starts at 12h15, with results and prize giving at 13:15.   For details of the race, and of how to sign up a team, please visit: https://espace.cern.ch/Running-Club/CERN-Relay The event is organised by the CERN Running Club with the support of the CERN Staff Association.  

THE SCHEME WITH THE MULTIPURPOSE RELAY FOR ECONOMY OF ELECTRIC ENERGY IN TO GRAIN THROWER

Directory of Open Access Journals (Sweden)

N. A. Mazukha

2015-01-01

Full Text Available The scheme for economy of electric energy during the work for an example of a grain thrower of the ZME 60 type (Voronezh Region, Semiluki on grain flows in rural economy is offered. Grain thrower can carry out the following technological operations: loading of grain in vehicles; loading and unloading of grain stores; mechanical shoveling of grain on the open areas; separation of grain with office of light impurity. In the scheme the relay 3UG3521/22t (SIEMENS firm is used. The relay can carry out multipurpose protection of engines and comprises the relay of the maximum current, the relay of the minimum current, a timer and the index relay. Temporary charts of the relay 3UG3521/22t are provided in the mode "without preservation" and in the mode with "preservation" for the OVER functions (reaction to growth of current and the UNDER function (reaction to recession of current. Use of the relay 3UG3521/22t allowed to receive protection at long start-up of electric motors, at an overload of electric motors, when idling (for economy of electric energy due to automatic shutdown of the conveyor and at break or jamming of the conveyor. Besides, in the scheme it is offered the multipurpose relay of tension (the relay of control of phases for protection of three engines of a grain thrower at not full-phase modes of a power line. The economy of electric energy can be received in case of, for example, the late actions of the operator for timely shutdown of the engine of a self-feed upon transition of a grain thrower to idling. In practice transition of a grain thrower to the mode of idling is quite often possible in process of reduction of amount of the thrown grain on a platform before a grain thrower. In practice transition of a grain thrower to the mode of idling is quite often possible in process of reduction of amount of the thrown grain on a platform before a grain thrower. The offered electric circuit can be used in the grain thrower and grain loaders

Energy-efficient cooperative protocols for full-duplex relay channels

KAUST Repository

Khafagy, Mohammad Galal

2013-12-01

In this work, energy-efficient cooperative protocols are studied for full-duplex relaying (FDR) with loopback interference. In these protocols, relay assistance is only sought under certain conditions on the different link outages to ensure effective cooperation. Recently, an energy-efficient selective decode-And-forward protocol was proposed for FDR, and was shown to outperform existing schemes in terms of outage. Here, we propose an incremental selective decode-And-forward protocol that offers additional power savings, while keeping the same outage performance. We compare the performance of the two protocols in terms of the end-to-end signal-to-noise ratio cumulative distribution function via closed-form expressions. Finally, we corroborate our theoretical results with simulation, and show the relative relay power savings in comparison to non-selective cooperation in which the relay cooperates regardless of channel conditions. © 2013 IEEE.

New results on performance analysis of opportunistic regenerative relaying

KAUST Repository

Tourki, Kamel

2013-12-01

In this paper, we investigate an opportunistic relaying scheme where the selected relay assists the source-destination (direct) communication. In our study, we consider a regenerative opportunistic relaying scheme in which the direct path may be unusable, and takes into account the effect of the possible erroneously detected and transmitted data at the selected relay. We first derive the signal-to-noise (SNR) statistics for each hop, which are used to determine accurate closed form expressions for end-to-end bit-error rate (BER) of binary phase-shift keying (BPSK) modulation and end-to-end outage probability for a transmission rate R over Rayleigh fading channels. Furthermore, we evaluate the asymptotical performance and deduce the diversity order. Finally, we validate our analysis by showing that performance simulation results coincide with our analytical results over linear network architecture. © 2013 Elsevier B.V.

Energy-efficient cooperative protocols for full-duplex relay channels

KAUST Repository

Khafagy, Mohammad Galal; Ismail, Amr; Alouini, Mohamed-Slim; Aï ssa, Sonia

2013-01-01

In this work, energy-efficient cooperative protocols are studied for full-duplex relaying (FDR) with loopback interference. In these protocols, relay assistance is only sought under certain conditions on the different link outages to ensure effective cooperation. Recently, an energy-efficient selective decode-And-forward protocol was proposed for FDR, and was shown to outperform existing schemes in terms of outage. Here, we propose an incremental selective decode-And-forward protocol that offers additional power savings, while keeping the same outage performance. We compare the performance of the two protocols in terms of the end-to-end signal-to-noise ratio cumulative distribution function via closed-form expressions. Finally, we corroborate our theoretical results with simulation, and show the relative relay power savings in comparison to non-selective cooperation in which the relay cooperates regardless of channel conditions. © 2013 IEEE.

Large Efficient Intelligent Heating Relay Station System

Science.gov (United States)

Wu, C. Z.; Wei, X. G.; Wu, M. Q.