WorldWideScience

Sample records for real-time distributed simulation

  1. SCI-Clone/32 - a distributed real time simulation system

    International Nuclear Information System (INIS)

    Wilks, C.F.

    1986-01-01

    Advances in engineering and in particular digital computers has enabled the simulation manufacturers to deliver a realism of a kind undreamt of a decade ago. 32-bit computers ranging in processor power from several hundred thousand instructions per second to many millions are at the heart of each simulator. Gould has pioneered digital computers in simulation with real time systems using shared memory, parallel processors, 64KByte cache, and shadow memory. The market is planning for higher iteration rates, lower life cycle costs, and the development of part task products. These can be met by distributing the tasks amongst nodal computers having a unique architecture for sharing data variables with minimal contention. (Auth.)

  2. Migrating to a real-time distributed parallel simulator architecture

    CSIR Research Space (South Africa)

    Duvenhage, B

    2007-07-01

    Full Text Available A legacy non-distributed logical time simulator is migrated to a distributed architecture to parallelise execution. The existing Discrete Time System Specification (DTSS) modelling formalism is retained to simplify the reuse of existing models...

  3. Real-time modeling and simulation of distribution feeder and distributed resources

    Science.gov (United States)

    Singh, Pawan

    The analysis of the electrical system dates back to the days when analog network analyzers were used. With the advent of digital computers, many programs were written for power-flow and short circuit analysis for the improvement of the electrical system. Real-time computer simulations can answer many what-if scenarios in the existing or the proposed power system. In this thesis, the standard IEEE 13-Node distribution feeder is developed and validated on a real-time platform OPAL-RT. The concept and the challenges of the real-time simulation are studied and addressed. Distributed energy resources include some of the commonly used distributed generation and storage devices like diesel engine, solar photovoltaic array, and battery storage system are modeled and simulated on a real-time platform. A microgrid encompasses a portion of an electric power distribution which is located downstream of the distribution substation. Normally, the microgrid operates in paralleled mode with the grid; however, scheduled or forced isolation can take place. In such conditions, the microgrid must have the ability to operate stably and autonomously. The microgrid can operate in grid connected and islanded mode, both the operating modes are studied in the last chapter. Towards the end, a simple microgrid controller modeled and simulated on the real-time platform is developed for energy management and protection for the microgrid.

  4. Design and simulation for real-time distributed processing systems

    International Nuclear Information System (INIS)

    Legrand, I.C.; Gellrich, A.; Gensah, U.; Leich, H.; Wegner, P.

    1996-01-01

    The aim of this work is to provide a proper framework for the simulation and the optimization of the event building, the on-line third level trigger, and complete event reconstruction processor farm for the future HERA-B experiment. A discrete event, process oriented, simulation developed in concurrent μC++ is used for modelling the farm nodes running with multi-tasking constraints and different types of switching elements and digital signal processors interconnected for distributing the data through the system. An adequate graphic interface to the simulation part which allows to monitor features on-line and to analyze trace files, provides a powerful development tool for evaluating and designing parallel processing architectures. Control software and data flow protocols for event building and dynamic processor allocation are presented for two architectural models. (author)

  5. Implementation of a Real-Time Microgrid Simulation Platform Based on Centralized and Distributed Management

    Directory of Open Access Journals (Sweden)

    Omid Abrishambaf

    2017-06-01

    Full Text Available Demand response and distributed generation are key components of power systems. Several challenges are raised at both technical and business model levels for integration of those resources in smart grids and microgrids. The implementation of a distribution network as a test bed can be difficult and not cost-effective; using computational modeling is not sufficient for producing realistic results. Real-time simulation allows us to validate the business model’s impact at the technical level. This paper comprises a platform supporting the real-time simulation of a microgrid connected to a larger distribution network. The implemented platform allows us to use both centralized and distributed energy resource management. Using an optimization model for the energy resource operation, a virtual power player manages all the available resources. Then, the simulation platform allows us to technically validate the actual implementation of the requested demand reduction in the scope of demand response programs. The case study has 33 buses, 220 consumers, and 68 distributed generators. It demonstrates the impact of demand response events, also performing resource management in the presence of an energy shortage.

  6. Real-Time Simulation and Hardware-in-the-Loop Testbed for Distribution Synchrophasor Applications

    Directory of Open Access Journals (Sweden)

    Matthias Stifter

    2018-04-01

    Full Text Available With the advent of Distribution Phasor Measurement Units (D-PMUs and Micro-Synchrophasors (Micro-PMUs, the situational awareness in power distribution systems is going to the next level using time-synchronization. However, designing, analyzing, and testing of such accurate measurement devices are still challenging. Due to the lack of available knowledge and sufficient history for synchrophasors’ applications at the power distribution level, the realistic simulation, and validation environments are essential for D-PMU development and deployment. This paper presents a vendor agnostic PMU real-time simulation and hardware-in-the-Loop (PMU-RTS-HIL testbed, which helps in multiple PMUs validation and studies. The network of real and virtual PMUs was built in a full time-synchronized environment for PMU applications’ validation. The proposed testbed also includes an emulated communication network (CNS layer to replicate bandwidth, packet loss and collisions conditions inherent to the PMUs data streams’ issues. Experimental results demonstrate the flexibility and scalability of the developed PMU-RTS-HIL testbed by producing large amounts of measurements under typical normal and abnormal distribution grid operation conditions.

  7. VERSE - Virtual Equivalent Real-time Simulation

    Science.gov (United States)

    Zheng, Yang; Martin, Bryan J.; Villaume, Nathaniel

    2005-01-01

    Distributed real-time simulations provide important timing validation and hardware in the- loop results for the spacecraft flight software development cycle. Occasionally, the need for higher fidelity modeling and more comprehensive debugging capabilities - combined with a limited amount of computational resources - calls for a non real-time simulation environment that mimics the real-time environment. By creating a non real-time environment that accommodates simulations and flight software designed for a multi-CPU real-time system, we can save development time, cut mission costs, and reduce the likelihood of errors. This paper presents such a solution: Virtual Equivalent Real-time Simulation Environment (VERSE). VERSE turns the real-time operating system RTAI (Real-time Application Interface) into an event driven simulator that runs in virtual real time. Designed to keep the original RTAI architecture as intact as possible, and therefore inheriting RTAI's many capabilities, VERSE was implemented with remarkably little change to the RTAI source code. This small footprint together with use of the same API allows users to easily run the same application in both real-time and virtual time environments. VERSE has been used to build a workstation testbed for NASA's Space Interferometry Mission (SIM PlanetQuest) instrument flight software. With its flexible simulation controls and inexpensive setup and replication costs, VERSE will become an invaluable tool in future mission development.

  8. Contribution of static and dynamic load balancing in a real-time distributed air defence simulation

    CSIR Research Space (South Africa)

    Duvenhage, B

    2008-05-01

    Full Text Available Simulations with a large number of model instances make use of parallel architectures to improve performance. When using such a parallel architecture a challenge is to effectively distribute the simulation objects across the processing platforms...

  9. Migrating to a real-time distributed parallel simulator architecture- An update

    CSIR Research Space (South Africa)

    Duvenhage, B

    2007-09-01

    Full Text Available A legacy non-distributed logical time simulator was previously migrated to a distributed architecture to parallelise execution. The existing Discrete Time System Specification (DTSS) modelling formalism was retained to simplify the reuse of existing...

  10. Network Reduction Algorithm for Developing Distribution Feeders for Real-Time Simulators: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Nagarajan, Adarsh; Nelson, Austin; Prabakar, Kumaraguru; Hoke, Andy; Asano, Marc; Ueda, Reid; Nepal, Shaili

    2017-06-15

    As advanced grid-support functions (AGF) become more widely used in grid-connected photovoltaic (PV) inverters, utilities are increasingly interested in their impacts when implemented in the field. These effects can be understood by modeling feeders in real-time systems and testing PV inverters using power hardware-in-the-loop (PHIL) techniques. This paper presents a novel feeder model reduction algorithm using a Monte Carlo method that enables large feeders to be solved and operated on real-time computing platforms. Two Hawaiian Electric feeder models in Synergi Electric's load flow software were converted to reduced order models in OpenDSS, and subsequently implemented in the OPAL-RT real-time digital testing platform. Smart PV inverters were added to the real-time model with AGF responses modeled after characterizing commercially available hardware inverters. Finally, hardware inverters were tested in conjunction with the real-time model using PHIL techniques so that the effects of AGFs on the choice feeders could be analyzed.

  11. Real-time distributed simulation using the Modular Modeling System interfaced to a Bailey NETWORK 90 system

    International Nuclear Information System (INIS)

    Edwards, R.M.; Turso, J.A.; Garcia, H.E.; Ghie, M.H.; Dharap, S.; Lee, S.

    1991-01-01

    The Modular Modeling System was adapted for real-time simulation testing of diagnostic expert systems in 1987. The early approach utilized an available general purpose mainframe computer which operated the simulation and diagnostic program in the multitasking environment of the mainframe. That research program was subsequently expanded to intelligent distributed control applications incorporating microprocessor based controllers with the aid of an equipment grant from the National Science Foundation (NSF). The Bailey NETWORK 90 microprocessor-based control system, acquired with the NSF grant, has been operational since April of 1990 and has been interfaced to both VAX mainframe and PC simulations of power plant processes in order to test and demonstrate advanced control and diagnostic concepts. This paper discusses the variety of techniques that have been used and which are under development to interface simulations and other distributed control functions to the Penn State Bailey system

  12. A MATLAB based Distributed Real-time Simulation of Lander-Orbiter-Earth Communication for Lunar Missions

    Science.gov (United States)

    Choudhury, Diptyajit; Angeloski, Aleksandar; Ziah, Haseeb; Buchholz, Hilmar; Landsman, Andre; Gupta, Amitava; Mitra, Tiyasa

    Lunar explorations often involve use of a lunar lander , a rover [1],[2] and an orbiter which rotates around the moon with a fixed radius. The orbiters are usually lunar satellites orbiting along a polar orbit to ensure visibility with respect to the rover and the Earth Station although with varying latency. Communication in such deep space missions is usually done using a specialized protocol like Proximity-1[3]. MATLAB simulation of Proximity-1 have been attempted by some contemporary researchers[4] to simulate all features like transmission control, delay etc. In this paper it is attempted to simulate, in real time, the communication between a tracking station on earth (earth station), a lunar orbiter and a lunar rover using concepts of Distributed Real-time Simulation(DRTS).The objective of the simulation is to simulate, in real-time, the time varying communication delays associated with the communicating elements with a facility to integrate specific simulation modules to study different aspects e.g. response due to a specific control command from the earth station to be executed by the rover. The hardware platform comprises four single board computers operating as stand-alone real time systems (developed by MATLAB xPC target and inter-networked using UDP-IP protocol). A time triggered DRTS approach is adopted. The earth station, the orbiter and the rover are programmed as three standalone real-time processes representing the communicating elements in the system. Communication from one communicating element to another constitutes an event which passes a state message from one element to another, augmenting the state of the latter. These events are handled by an event scheduler which is the fourth real-time process. The event scheduler simulates the delay in space communication taking into consideration the distance between the communicating elements. A unique time synchronization algorithm is developed which takes into account the large latencies in space

  13. Research in Distributed Real-Time Systems

    Science.gov (United States)

    Mukkamala, R.

    1997-01-01

    This document summarizes the progress we have made on our study of issues concerning the schedulability of real-time systems. Our study has produced several results in the scalability issues of distributed real-time systems. In particular, we have used our techniques to resolve schedulability issues in distributed systems with end-to-end requirements. During the next year (1997-98), we propose to extend the current work to address the modeling and workload characterization issues in distributed real-time systems. In particular, we propose to investigate the effect of different workload models and component models on the design and the subsequent performance of distributed real-time systems.

  14. Archtecture of distributed real-time systems

    OpenAIRE

    Wing Leung, Cheuk

    2013-01-01

    CRAFTERS (Constraint and Application Driven Framework for Tailoring Embedded Real-time System) project aims to address the problem of uncertainty and heterogeneity in a distributed system by providing seamless, portable connectivity and middleware. This thesis contributes to the project by investigating the techniques that can be used in a distributed real-time embedded system. The conclusion is that, there is a list of specifications to be meet in order to provide a transparent and real-time...

  15. Implementing a low cost distributed architecture for real-time behavioural modelling and simulation

    CSIR Research Space (South Africa)

    Le Roux, WH

    2006-06-01

    Full Text Available at different levels of which some are: 1. Comprehensiveness (completeness) – Are the sun and moon positions accurate for the time of day and time of year in the flight simulator? Are wind gusts taken into account for the projectile trajectory? 2... system, referred to as the Virtual GBADS Demonstrator (VGD), to the first GBADS acquisition phase. The GBADS procurement programme follows a phased approach of which acquisition of the SABLE2 Air Defence System forms the first phase [1...

  16. Real-time modeling of heat distributions

    Science.gov (United States)

    Hamann, Hendrik F.; Li, Hongfei; Yarlanki, Srinivas

    2018-01-02

    Techniques for real-time modeling temperature distributions based on streaming sensor data are provided. In one aspect, a method for creating a three-dimensional temperature distribution model for a room having a floor and a ceiling is provided. The method includes the following steps. A ceiling temperature distribution in the room is determined. A floor temperature distribution in the room is determined. An interpolation between the ceiling temperature distribution and the floor temperature distribution is used to obtain the three-dimensional temperature distribution model for the room.

  17. Real time simulator for material testing reactor

    Energy Technology Data Exchange (ETDEWEB)

    Takemoto, Noriyuki; Imaizumi, Tomomi; Izumo, Hironobu; Hori, Naohiko; Suzuki, Masahide [Japan Atomic Energy Agency, Oarai Research and Development Center, Oarai, Ibaraki (Japan); Ishitsuka, Tatsuo; Tamura, Kazuo [ITOCHU Techno-Solutions Corp., Tokyo (Japan)

    2012-03-15

    Japan Atomic Energy Agency (JAEA) is now developing a real time simulator for a material testing reactor based on Japan Materials Testing Reactor (JMTR). The simulator treats reactor core system, primary and secondary cooling system, electricity system and irradiation facility systems. Possible simulations are normal reactor operation, unusual transient operation and accidental operation. The developed simulator also contains tool to revise/add facility in it for the future development. (author)

  18. Real time simulator for material testing reactor

    International Nuclear Information System (INIS)

    Takemoto, Noriyuki; Imaizumi, Tomomi; Izumo, Hironobu; Hori, Naohiko; Suzuki, Masahide; Ishitsuka, Tatsuo; Tamura, Kazuo

    2012-01-01

    Japan Atomic Energy Agency (JAEA) is now developing a real time simulator for a material testing reactor based on Japan Materials Testing Reactor (JMTR). The simulator treats reactor core system, primary and secondary cooling system, electricity system and irradiation facility systems. Possible simulations are normal reactor operation, unusual transient operation and accidental operation. The developed simulator also contains tool to revise/add facility in it for the future development. (author)

  19. Conversion and Validation of Distribution System Model from a QSTS-Based Tool to a Real-Time Dynamic Phasor Simulator: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Chamana, Manohar; Prabakar, Kumaraguru; Palmintier, Bryan; Baggu, Murali M.

    2017-04-11

    A software process is developed to convert distribution network models from a quasi-static time-series tool (OpenDSS) to a real-time dynamic phasor simulator (ePHASORSIM). The description of this process in this paper would be helpful for researchers who intend to perform similar conversions. The converter could be utilized directly by users of real-time simulators who intend to perform software-in-the-loop or hardware-in-the-loop tests on large distribution test feeders for a range of use cases, including testing functions of advanced distribution management systems against a simulated distribution system. In the future, the developers intend to release the conversion tool as open source to enable use by others.

  20. Conversion and Validation of Distribution System Model from a QSTS-Based Tool to a Real-Time Dynamic Phasor Simulator

    Energy Technology Data Exchange (ETDEWEB)

    Chamana, Manohar; Prabakar, Kumaraguru; Palmintier, Bryan; Baggu, Murali M.

    2017-05-11

    A software process is developed to convert distribution network models from a quasi-static time-series tool (OpenDSS) to a real-time dynamic phasor simulator (ePHASORSIM). The description of this process in this paper would be helpful for researchers who intend to perform similar conversions. The converter could be utilized directly by users of real-time simulators who intend to perform software-in-the-loop or hardware-in-the-loop tests on large distribution test feeders for a range of use cases, including testing functions of advanced distribution management systems against a simulated distribution system. In the future, the developers intend to release the conversion tool as open source to enable use by others.

  1. Real-time inextensible surgical thread simulation.

    Science.gov (United States)

    Xu, Lang; Liu, Qian

    2018-03-27

    This paper discusses a real-time simulation method of inextensible surgical thread based on the Cosserat rod theory using position-based dynamics (PBD). The method realizes stable twining and knotting of surgical thread while including inextensibility, bending, twisting and coupling effects. The Cosserat rod theory is used to model the nonlinear elastic behavior of surgical thread. The surgical thread model is solved with PBD to achieve a real-time, extremely stable simulation. Due to the one-dimensional linear structure of surgical thread, the direct solution of the distance constraint based on tridiagonal matrix algorithm is used to enhance stretching resistance in every constraint projection iteration. In addition, continuous collision detection and collision response guarantee a large time step and high performance. Furthermore, friction is integrated into the constraint projection process to stabilize the twining of multiple threads and complex contact situations. Through comparisons with existing methods, the surgical thread maintains constant length under large deformation after applying the direct distance constraint in our method. The twining and knotting of multiple threads correspond to stable solutions to contact and friction forces. A surgical suture scene is also modeled to demonstrate the practicality and simplicity of our method. Our method achieves stable and fast simulation of inextensible surgical thread. Benefiting from the unified particle framework, the rigid body, elastic rod, and soft body can be simultaneously simulated. The method is appropriate for applications in virtual surgery that require multiple dynamic bodies.

  2. CUDA-based real time surgery simulation.

    Science.gov (United States)

    Liu, Youquan; De, Suvranu

    2008-01-01

    In this paper we present a general software platform that enables real time surgery simulation on the newly available compute unified device architecture (CUDA)from NVIDIA. CUDA-enabled GPUs harness the power of 128 processors which allow data parallel computations. Compared to the previous GPGPU, it is significantly more flexible with a C language interface. We report implementation of both collision detection and consequent deformation computation algorithms. Our test results indicate that the CUDA enables a twenty times speedup for collision detection and about fifteen times speedup for deformation computation on an Intel Core 2 Quad 2.66 GHz machine with GeForce 8800 GTX.

  3. A distributed real-time operating system

    International Nuclear Information System (INIS)

    Tuynman, F.; Hertzberger, L.O.

    1984-07-01

    A distributed real-time operating system, Fados, has been developed for an embedded multi-processor system. The operating system is based on a host target approach and provides for communication between arbitrary processes on host and target machine. The facilities offered are, apart from process communication, access to the file system on the host by programs on the target machine and monitoring and debugging of programs on the target machine from the host. The process communication has been designed in such a way that the possibilities are the same as those offered by the Ada programming language. The operating system is implemented on a MC 68000 based multiprocessor system in combination with a Unix host. (orig.)

  4. High performance real-time flight simulation at NASA Langley

    Science.gov (United States)

    Cleveland, Jeff I., II

    1994-01-01

    In order to meet the stringent time-critical requirements for real-time man-in-the-loop flight simulation, computer processing operations must be deterministic and be completed in as short a time as possible. This includes simulation mathematical model computational and data input/output to the simulators. In 1986, in response to increased demands for flight simulation performance, personnel at NASA's Langley Research Center (LaRC), working with the contractor, developed extensions to a standard input/output system to provide for high bandwidth, low latency data acquisition and distribution. The Computer Automated Measurement and Control technology (IEEE standard 595) was extended to meet the performance requirements for real-time simulation. This technology extension increased the effective bandwidth by a factor of ten and increased the performance of modules necessary for simulator communications. This technology is being used by more than 80 leading technological developers in the United States, Canada, and Europe. Included among the commercial applications of this technology are nuclear process control, power grid analysis, process monitoring, real-time simulation, and radar data acquisition. Personnel at LaRC have completed the development of the use of supercomputers for simulation mathematical model computational to support real-time flight simulation. This includes the development of a real-time operating system and the development of specialized software and hardware for the CAMAC simulator network. This work, coupled with the use of an open systems software architecture, has advanced the state of the art in real time flight simulation. The data acquisition technology innovation and experience with recent developments in this technology are described.

  5. Real time simulation method for fast breeder reactors dynamics

    International Nuclear Information System (INIS)

    Miki, Tetsushi; Mineo, Yoshiyuki; Ogino, Takamichi; Kishida, Koji; Furuichi, Kenji.

    1985-01-01

    The development of multi-purpose real time simulator models with suitable plant dynamics was made; these models can be used not only in training operators but also in designing control systems, operation sequences and many other items which must be studied for the development of new type reactors. The prototype fast breeder reactor ''Monju'' is taken as an example. Analysis is made on various factors affecting the accuracy and computer load of its dynamic simulation. A method is presented which determines the optimum number of nodes in distributed systems and time steps. The oscillations due to the numerical instability are observed in the dynamic simulation of evaporators with a small number of nodes, and a method to cancel these oscillations is proposed. It has been verified through the development of plant dynamics simulation codes that these methods can provide efficient real time dynamics models of fast breeder reactors. (author)

  6. Simulating Real-Time Aspects of Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Christian Nastasi

    2010-01-01

    Full Text Available Wireless Sensor Networks (WSNs technology has been mainly used in the applications with low-frequency sampling and little computational complexity. Recently, new classes of WSN-based applications with different characteristics are being considered, including process control, industrial automation and visual surveillance. Such new applications usually involve relatively heavy computations and also present real-time requirements as bounded end-to- end delay and guaranteed Quality of Service. It becomes then necessary to employ proper resource management policies, not only for communication resources but also jointly for computing resources, in the design and development of such WSN-based applications. In this context, simulation can play a critical role, together with analytical models, for validating a system design against the parameters of Quality of Service demanded for. In this paper, we present RTNS, a publicly available free simulation tool which includes Operating System aspects in wireless distributed applications. RTNS extends the well-known NS-2 simulator with models of the CPU, the Real-Time Operating System and the application tasks, to take into account delays due to the computation in addition to the communication. We demonstrate the benefits of RTNS by presenting our simulation study for a complex WSN-based multi-view vision system for real-time event detection.

  7. Variable slip wind generator modeling for real-time simulation

    Energy Technology Data Exchange (ETDEWEB)

    Gagnon, R.; Brochu, J.; Turmel, G. [Hydro-Quebec, Varennes, PQ (Canada). IREQ

    2006-07-01

    A model of a wind turbine using a variable slip wound-rotor induction machine was presented. The model was created as part of a library of generic wind generator models intended for wind integration studies. The stator winding of the wind generator was connected directly to the grid and the rotor was driven by the turbine through a drive train. The variable resistors was synthesized by an external resistor in parallel with a diode rectifier. A forced-commutated power electronic device (IGBT) was connected to the wound rotor by slip rings and brushes. Simulations were conducted in a Matlab/Simulink environment using SimPowerSystems blocks to model power systems elements and Simulink blocks to model the turbine, control system and drive train. Detailed descriptions of the turbine, the drive train and the control system were provided. The model's implementation in the simulator was also described. A case study demonstrating the real-time simulation of a wind generator connected at the distribution level of a power system was presented. Results of the case study were then compared with results obtained from the SimPowerSystems off-line simulation. Results showed good agreement between the waveforms, demonstrating the conformity of the real-time and the off-line simulations. The capability of Hypersim for real-time simulation of wind turbines with power electronic converters in a distribution network was demonstrated. It was concluded that hardware-in-the-loop (HIL) simulation of wind turbine controllers for wind integration studies in power systems is now feasible. 5 refs., 1 tab., 6 figs.

  8. Real-Time ECG Simulation for Hybrid Mock Circulatory Loops.

    Science.gov (United States)

    Korn, Leonie; Rüschen, Daniel; Zander, Niklas; Leonhardt, Steffen; Walter, Marian

    2018-02-01

    Classically, mock circulatory loops only simulate mechanical properties of the circulation. To connect the hydraulic world with electrophysiology, we present a real-time electrical activity model of the heart and show how to integrate this model into a real-time mock loop simulation. The model incorporates a predefined conduction pathway and a simplified volume conductor to solve the bidomain equations and the forward problem of electrocardiography, resulting in a physiological simulation of the electrocardiogram (ECG) at arbitrary electrode positions. A complete physiological simulation of the heart's excitation would be too CPU intensive. Thus, in our model, complexity was reduced to allow real-time simulation of ECG-triggered medical systems in vitro; this decreases time and cost in the development process. Conversely, the presented model can still be adapted to various pathologies by locally changing the properties of the heart's conduction pathway. To simulate the ECG, the heart is divided into suitable areas, which are innervated by the hierarchically structured conduction system. To distinguish different cardiac regions, a segmentation of the heart was performed. In these regions, Prim's algorithm was applied to identify the directed minimal spanning trees for conduction orientation. Each node of the tree was assigned to a cardiac action potential generated by its hybrid automaton to represent the heart's conduction system by the spatial distribution of action potentials. To generate the ECG output, the bidomain equations were implemented and a simple model of the volume conductor of the body was used to solve the forward problem of electrocardiography. As a result, the model simulates potentials at arbitrary electrode positions in real-time. To verify the developed real-time ECG model, measurements were made within a hybrid mock circulatory loop, including a simple ECG-triggered ventricular assist device control. The model's potential value is to simulate

  9. Distributed Real-Time Embedded Video Processing

    National Research Council Canada - National Science Library

    Lv, Tiehan

    2004-01-01

    .... A deployable multi-camera video system must perform distributed computation, including computation near the camera as well as remote computations, in order to meet performance and power requirements...

  10. Real time simulation techniques in Taiwan - Maanshan compact simulator

    International Nuclear Information System (INIS)

    Liang, K.-S.; Chuang, Y.-M.; Ko, H.-T.

    2004-01-01

    Recognizing the demand and potential market of simulators in various industries, a special project for real time simulation technology transfer was initiated in Taiwan in 1991. In this technology transfer program, the most advanced real-time dynamic modules for nuclear power simulation were introduced. Those modules can be divided into two categories; one is modeling related to catch dynamic response of each system, and the other is computer related to provide special real time computing environment and man-machine interface. The modeling related modules consist of the thermodynamic module, the three-dimensional core neutronics module and the advanced balance of plant module. As planned in the project, the technology transfer team should build a compact simulator for the Maanshan power plant before the end of the project to demonstrate the success of the technology transfer program. The compact simulator was designed to support the training from the regular full scope simulator which was already equipped in the Maanshan plant. The feature of this compact simulator focused on providing know-why training by the enhanced graphic display. The potential users were identified as senior operators, instructors and nuclear engineers. Total about 13 important systems were covered in the scope of the compact simulator, and multi-graphic displays from three color monitors mounted on the 10 feet compact panel were facilitated to help the user visualize detailed phenomena under scenarios of interest. (author)

  11. Parametric Room Acoustic workflows with real-time acoustic simulation

    DEFF Research Database (Denmark)

    Parigi, Dario

    2017-01-01

    The paper investigates and assesses the opportunities that real-time acoustic simulation offer to engage in parametric acoustics workflow and to influence architectural designs from early design stages......The paper investigates and assesses the opportunities that real-time acoustic simulation offer to engage in parametric acoustics workflow and to influence architectural designs from early design stages...

  12. Innovative tools for real-time simulation of dynamic systems

    NARCIS (Netherlands)

    Palli, Gianluca; Carloni, Raffaella; Melchiorri, Claudio

    2008-01-01

    In this paper, we present a software architecture, based on RTAI-Linux, for the real-time simulation of dynamic systems and for the rapid prototyping of digital controllers. Our aim is to simplify the testing phase of digital controllers by providing the real-time simulation of the plant with the

  13. Design a Fault Tolerance for Real Time Distributed System

    OpenAIRE

    Ban M. Khammas

    2012-01-01

    This paper designed a fault tolerance for soft real time distributed system (FTRTDS). This system is designed to be independently on specific mechanisms and facilities of the underlying real time distributed system. It is designed to be distributed on all the computers in the distributed system and controlled by a central unit.Besides gathering information about a target program spontaneously, it provides information about the target operating system and the target hardware in order to diagno...

  14. Real Time Synchronization for Creativity in Distributed Innovation Teams

    DEFF Research Database (Denmark)

    Peitersen, Dennis Kjaersgaard; Dolog, Peter; Pedersen, Esben Staunsbjerg

    2009-01-01

    In this paper we introduce a synchronization approach for real time collaborative sketching for creativity in distributed innovation teams. We base our approach on reverse AJAX. This way we ensure scalable solution for real time drawing and sketching important in creativity settings....

  15. Real time computer system with distributed microprocessors

    International Nuclear Information System (INIS)

    Heger, D.; Steusloff, H.; Syrbe, M.

    1979-01-01

    The usual centralized structure of computer systems, especially of process computer systems, cannot sufficiently use the progress of very large-scale integrated semiconductor technology with respect to increasing the reliability and performance and to decreasing the expenses especially of the external periphery. This and the increasing demands on process control systems has led the authors to generally examine the structure of such systems and to adapt it to the new surroundings. Computer systems with distributed, optical fibre-coupled microprocessors allow a very favourable problem-solving with decentralized controlled buslines and functional redundancy with automatic fault diagnosis and reconfiguration. A fit programming system supports these hardware properties: PEARL for multicomputer systems, dynamic loader, processor and network operating system. The necessary design principles for this are proved mainly theoretically and by value analysis. An optimal overall system of this new generation of process control systems was established, supported by results of 2 PDV projects (modular operating systems, input/output colour screen system as control panel), for the purpose of testing by apllying the system for the control of 28 pit furnaces of a steel work. (orig.) [de

  16. Real-time communication for distributed plasma control systems

    Energy Technology Data Exchange (ETDEWEB)

    Luchetta, A. [Consorzio RFX, Associazione Euratom-ENEA sulla Fusione, Corso Stati Uniti 4, Padova 35127 (Italy)], E-mail: adriano.luchetta@igi.cnr.it; Barbalace, A.; Manduchi, G.; Soppelsa, A.; Taliercio, C. [Consorzio RFX, Associazione Euratom-ENEA sulla Fusione, Corso Stati Uniti 4, Padova 35127 (Italy)

    2008-04-15

    Real-time control applications will benefit in the near future from the enhanced performance provided by multi-core processor architectures. Nevertheless real-time communication will continue to be critical in distributed plasma control systems where the plant under control typically is distributed over a wide area. At RFX-mod real-time communication is crucial for hard real-time plasma control, due to the distributed architecture of the system, which consists of several VMEbus stations. The system runs under VxWorks and uses Gigabit Ethernet for sub-millisecond real-time communication. To optimize communication in the system, a set of detailed measurements has been carried out on the target platforms (Motorola MVME5100 and MVME5500) using either the VxWorks User Datagram Protocol (UDP) stack or raw communication based on the data link layer. Measurements have been carried out also under Linux, using its UDP stack or, in alternative, RTnet, an open source hard real-time network protocol stack. RTnet runs under Xenomai or RTAI, two popular real-time extensions based on the Linux kernel. The paper reports on the measurements carried out and compares the results, showing that the performance obtained by using open source code is suitable for sub-millisecond real-time communication in plasma control.

  17. Real-time GPS Signal Simulator

    Data.gov (United States)

    National Aeronautics and Space Administration — With a minimal FTE investment and no additional procurement funds, the development of a low fidelity orbital GPS Signal simulator would is possible.  This IRAD...

  18. Distributed, Embedded and Real-time Java Systems

    CERN Document Server

    Wellings, Andy

    2012-01-01

    Research on real-time Java technology has been prolific over the past decade, leading to a large number of corresponding hardware and software solutions, and frameworks for distributed and embedded real-time Java systems.  This book is aimed primarily at researchers in real-time embedded systems, particularly those who wish to understand the current state of the art in using Java in this domain.  Much of the work in real-time distributed, embedded and real-time Java has focused on the Real-time Specification for Java (RTSJ) as the underlying base technology, and consequently many of the Chapters in this book address issues with, or solve problems using, this framework. Describes innovative techniques in: scheduling, memory management, quality of service and communication systems supporting real-time Java applications; Includes coverage of multiprocessor embedded systems and parallel programming; Discusses state-of-the-art resource management for embedded systems, including Java’s real-time garbage collect...

  19. Turbine modelling for real time simulators

    International Nuclear Information System (INIS)

    Oliveira Barroso, A.C. de; Araujo Filho, F. de

    1992-01-01

    A model for vapor turbines and its peripherals has been developed. All the important variables have been included and emphasis has been given for the computational efficiency to obtain a model able to simulate all the modeled equipment. (A.C.A.S.)

  20. Distributed Issues for Ada Real-Time Systems

    Science.gov (United States)

    1990-07-23

    NUMBERS Distributed Issues for Ada Real - Time Systems MDA 903-87- C- 0056 S. AUTHOR(S) Thomas E. Griest 7. PERFORMING ORGANiZATION NAME(S) AND ADORESS(ES) 8...considerations. I Adding to the problem of distributed real - time systems is the issue of maintaining a common sense of time among all of the processors...because -omeone is waiting for the final output of a very large set of computations. However in real - time systems , consistent meeting of short-term

  1. A Distributed Computing Network for Real-Time Systems.

    Science.gov (United States)

    1980-11-03

    7 ) AU2 o NAVA TUNDEWATER SY$TEMS CENTER NEWPORT RI F/G 9/2 UIS RIBUT E 0 COMPUTIN G N LTWORK FOR REAL - TIME SYSTEMS .(U) UASSIFIED NOV Al 6 1...MORAIS - UT 92 dLEVEL c A Distributed Computing Network for Real - Time Systems . 11 𔃺-1 Gordon E/Morson I7 y tm- ,r - t "en t As J 2 -p .. - 7 I’ cNaval...NUMBER TD 5932 / N 4. TITLE mand SubotI. S. TYPE OF REPORT & PERIOD COVERED A DISTRIBUTED COMPUTING NETWORK FOR REAL - TIME SYSTEMS 6. PERFORMING ORG

  2. Boat, wake, and wave real-time simulation

    Science.gov (United States)

    Świerkowski, Leszek; Gouthas, Efthimios; Christie, Chad L.; Williams, Owen M.

    2009-05-01

    We describe the extension of our real-time scene generation software VIRSuite to include the dynamic simulation of small boats and their wakes within an ocean environment. Extensive use has been made of the programmabilty available in the current generation of GPUs. We have demonstrated that real-time simulation is feasible, even including such complexities as dynamical calculation of the boat motion, wake generation and calculation of an FFTgenerated sea state.

  3. Processor tradeoffs in distributed real-time systems

    Science.gov (United States)

    Krishna, C. M.; Shin, Kang G.; Bhandari, Inderpal S.

    1987-01-01

    The problem of the optimization of the design of real-time distributed systems is examined with reference to a class of computer architectures similar to the continuously reconfigurable multiprocessor flight control system structure, CM2FCS. Particular attention is given to the impact of processor replacement and the burn-in time on the probability of dynamic failure and mean cost. The solution is obtained numerically and interpreted in the context of real-time applications.

  4. The design of a real-time distributed system

    International Nuclear Information System (INIS)

    Hertzberger, L.O.; Tuynman, F.; Mullender, S.J.; Poletiek, G.; Vermeulen, J.C.; Renesse, R. van; Tanenbaum, A.S.

    1986-01-01

    In modern physics experiments an increasing number and variety of programmable processors is used. As a consequence, a software environment is needed that provides an integrated approach to development, testing and use of real-time distributed software. This contribution is based on work being done in the AMOEBA Distributed Operating System Project and the FADOS Real-Time Distributed Operating System Project. A short description of both systems is presented as an example of how basic real-time operating system services can be organized. AMOEBA is the result of fundamental research in the field of distributed operating systems, while FADOS has been designed for applications as encountered in experimental high-energy physics. (Auth.)

  5. Distributed digital real-time control system for TCV tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Le, H.B. [École Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas (CRPP), Association EURATOM-Confédération Suisse, CH-1015 Lausanne (Switzerland); Felici, F. [Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Paley, J.I.; Duval, B.P.; Moret, J.-M.; Coda, S.; Sauter, O.; Fasel, D.; Marmillod, P. [École Polytechnique Fédérale de Lausanne (EPFL), Centre de Recherches en Physique des Plasmas (CRPP), Association EURATOM-Confédération Suisse, CH-1015 Lausanne (Switzerland)

    2014-03-15

    Coder), into a Linux shared library (“.so” file) and distributed to target nodes in the discharge preparation phase. During the TCV discharge, an application on each node is executed that dynamically loads the shared library at runtime. In order to obtain reliable and reproducible real time execution of the algorithm, all interrupts to the CPU on each node are suspended just before firing the shot and re-enabled afterwards. Since installation, the new digital control system has been used for a multitude of plasma control applications, ranging from basic experiments of coil current and density control to advanced experiments of MHD (magnetohydrodynamics) and plasma profile control, as well as real-time plasma transport simulations. Recently, a real-time version of a plasma equilibrium reconstruction code was developed and implemented, providing the future possibility to control the plasma shape and profiles directly during the discharge evolution. This paper presents the architecture of the new control system, its integration into the TCV plant and a sample of control applications used for TCV plasma discharges.

  6. Real-time hybrid simulation using the convolution integral method

    International Nuclear Information System (INIS)

    Kim, Sung Jig; Christenson, Richard E; Wojtkiewicz, Steven F; Johnson, Erik A

    2011-01-01

    This paper proposes a real-time hybrid simulation method that will allow complex systems to be tested within the hybrid test framework by employing the convolution integral (CI) method. The proposed CI method is potentially transformative for real-time hybrid simulation. The CI method can allow real-time hybrid simulation to be conducted regardless of the size and complexity of the numerical model and for numerical stability to be ensured in the presence of high frequency responses in the simulation. This paper presents the general theory behind the proposed CI method and provides experimental verification of the proposed method by comparing the CI method to the current integration time-stepping (ITS) method. Real-time hybrid simulation is conducted in the Advanced Hazard Mitigation Laboratory at the University of Connecticut. A seismically excited two-story shear frame building with a magneto-rheological (MR) fluid damper is selected as the test structure to experimentally validate the proposed method. The building structure is numerically modeled and simulated, while the MR damper is physically tested. Real-time hybrid simulation using the proposed CI method is shown to provide accurate results

  7. Real-time Java simulations of multiple interference dielectric filters

    Science.gov (United States)

    Kireev, Alexandre N.; Martin, Olivier J. F.

    2008-12-01

    An interactive Java applet for real-time simulation and visualization of the transmittance properties of multiple interference dielectric filters is presented. The most commonly used interference filters as well as the state-of-the-art ones are embedded in this platform-independent applet which can serve research and education purposes. The Transmittance applet can be freely downloaded from the site http://cpc.cs.qub.ac.uk. Program summaryProgram title: Transmittance Catalogue identifier: AEBQ_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEBQ_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 5778 No. of bytes in distributed program, including test data, etc.: 90 474 Distribution format: tar.gz Programming language: Java Computer: Developed on PC-Pentium platform Operating system: Any Java-enabled OS. Applet was tested on Windows ME, XP, Sun Solaris, Mac OS RAM: Variable Classification: 18 Nature of problem: Sophisticated wavelength selective multiple interference filters can include some tens or even hundreds of dielectric layers. The spectral response of such a stack is not obvious. On the other hand, there is a strong demand from application designers and students to get a quick insight into the properties of a given filter. Solution method: A Java applet was developed for the computation and the visualization of the transmittance of multilayer interference filters. It is simple to use and the embedded filter library can serve educational purposes. Also, its ability to handle complex structures will be appreciated as a useful research and development tool. Running time: Real-time simulations

  8. Distributed computing for real-time petroleum reservoir monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Ayodele, O. R. [University of Alberta, Edmonton, AB (Canada)

    2004-05-01

    Computer software architecture is presented to illustrate how the concept of distributed computing can be applied to real-time reservoir monitoring processes, permitting the continuous monitoring of the dynamic behaviour of petroleum reservoirs at much shorter intervals. The paper describes the fundamental technologies driving distributed computing, namely Java 2 Platform Enterprise edition (J2EE) by Sun Microsystems, and the Microsoft Dot-Net (Microsoft.Net) initiative, and explains the challenges involved in distributed computing. These are: (1) availability of permanently placed downhole equipment to acquire and transmit seismic data; (2) availability of high bandwidth to transmit the data; (3) security considerations; (4) adaptation of existing legacy codes to run on networks as downloads on demand; and (5) credibility issues concerning data security over the Internet. Other applications of distributed computing in the petroleum industry are also considered, specifically MWD, LWD and SWD (measurement-while-drilling, logging-while-drilling, and simulation-while-drilling), and drill-string vibration monitoring. 23 refs., 1 fig.

  9. Real-time Control Mediation in Agile Distributed Software Development

    DEFF Research Database (Denmark)

    Persson, John Stouby; Aaen, Ivan; Mathiassen, Lars

    2008-01-01

    Agile distributed environments pose particular challenges related to control of quality and collaboration in software development. Moreover, while face-to-face interaction is fundamental in agile development, distributed environments must rely extensively on mediated interactions. On this backdrop...... control was mediated over distance by technology through real-time exchanges. Contrary to previous research, the analysis suggests that both formal and informal elements of real-time mediated control were used; that evolving goals and adjustment of expectations were two of the main issues in real......-time mediated control exchanges; and, that the actors, despite distances in space and culture, developed a clan-like pattern mediated by technology to help control quality and collaboration in software development....

  10. An approach to a real-time distribution system

    Science.gov (United States)

    Kittle, Frank P., Jr.; Paddock, Eddie J.; Pocklington, Tony; Wang, Lui

    1990-01-01

    The requirements of a real-time data distribution system are to provide fast, reliable delivery of data from source to destination with little or no impact to the data source. In this particular case, the data sources are inside an operational environment, the Mission Control Center (MCC), and any workstation receiving data directly from the operational computer must conform to the software standards of the MCC. In order to supply data to development workstations outside of the MCC, it is necessary to use gateway computers that prevent unauthorized data transfer back to the operational computers. Many software programs produced on the development workstations are targeted for real-time operation. Therefore, these programs must migrate from the development workstation to the operational workstation. It is yet another requirement for the Data Distribution System to ensure smooth transition of the data interfaces for the application developers. A standard data interface model has already been set up for the operational environment, so the interface between the distribution system and the application software was developed to match that model as closely as possible. The system as a whole therefore allows the rapid development of real-time applications without impacting the data sources. In summary, this approach to a real-time data distribution system provides development users outside of the MCC with an interface to MCC real-time data sources. In addition, the data interface was developed with a flexible and portable software design. This design allows for the smooth transition of new real-time applications to the MCC operational environment.

  11. Towards Real Time Simulation of Ship-Ship Interaction

    DEFF Research Database (Denmark)

    Lindberg, Ole; Bingham, Harry B.; Engsig-Karup, Allan Peter

    2012-01-01

    We present recent and preliminary work directed towards the development of a simplified, physics-based model for improved simulation of ship-ship interaction that can be used for both analysis and real-time computing (i.e. with real-time constraints due to visualization). The goal is to implement...... accurate (realistic) and much faster ship-wave and ship-ship simulations than are currently possible. The coupling of simulation with visualization should improve the visual experience such that it can be perceived as more realistic in training. Today the state-of-art in real-time ship-ship interaction...... is for efficiency reasons and time-constraints in visualization based on model experiments in towing tanks and precomputed force tables. We anticipate that the fast, and highly parallel, algorithm described by Engsig-Karup et al. [2011] for execution on affordable modern high-throughput Graphics Processing Units...

  12. Real-time simulation of large-scale floods

    Science.gov (United States)

    Liu, Q.; Qin, Y.; Li, G. D.; Liu, Z.; Cheng, D. J.; Zhao, Y. H.

    2016-08-01

    According to the complex real-time water situation, the real-time simulation of large-scale floods is very important for flood prevention practice. Model robustness and running efficiency are two critical factors in successful real-time flood simulation. This paper proposed a robust, two-dimensional, shallow water model based on the unstructured Godunov- type finite volume method. A robust wet/dry front method is used to enhance the numerical stability. An adaptive method is proposed to improve the running efficiency. The proposed model is used for large-scale flood simulation on real topography. Results compared to those of MIKE21 show the strong performance of the proposed model.

  13. The Design of a Real-Time Distributed System

    NARCIS (Netherlands)

    Hertzberger, L.O.; Mullender, S.J.; Poletiek, G.; van Renesse, R.; Tanenbaum, A.S.; Tuynman, F.; Vermeulen, J.C.

    1986-01-01

    In modern physics experiments an increasing number and variety of programmable processors is used. As a consequence, a software environment is needed that provides an integrated approach to development, testing and use of real-time distributed software. This contribution is based on work being done

  14. ISSUES IN MOBILE DISTRIBUTED REAL TIME DATABASES: PERFORMANCE AND REVIEW

    OpenAIRE

    VISHNU SWAROOP,; Gyanendra Kumar Gupta,; UDAI SHANKER

    2011-01-01

    Increase in handy and small electronic devices in computing fields; it makes the computing more popularand useful in business. Tremendous advances in wireless networks and portable computing devices have led to development of mobile computing. Support of real time database system depending upon thetiming constraints, due to availability of data distributed database, and ubiquitous computing pull the mobile database concept, which emerges them in a new form of technology as mobile distributed ...

  15. Real-Time Simulation of Ship Impact for Crew Training

    DEFF Research Database (Denmark)

    Simonsen, Bo Cerup

    2003-01-01

    Real-time simulation of marine accidents and representation in a realistic, virtual environment may be an efficient way to train emergency procedures for ship?s crews and thus improve safety at sea. However, although various fast, simplified methods have been presented over the past decades...

  16. Testing power system controllers by real-time simulation

    DEFF Research Database (Denmark)

    Venne, Philippe; Guillaud, Xavier; Sirois, Frédéric

    2007-01-01

    In this paper, we present a number of state-of-the art methods for testing power system controllers based on the use of a real-time power system simulator. After introducing Hypersim, we list and discuss the different means of connection between the controller under tests and the power system...

  17. Reduction Methods for Real-time Simulations in Hybrid Testing

    DEFF Research Database (Denmark)

    Andersen, Sebastian

    2016-01-01

    Hybrid testing constitutes a cost-effective experimental full scale testing method. The method was introduced in the 1960's by Japanese researchers, as an alternative to conventional full scale testing and small scale material testing, such as shake table tests. The principle of the method...... is performed on a glass fibre reinforced polymer composite box girder. The test serves as a pilot test for prospective real-time tests on a wind turbine blade. The Taylor basis is implemented in the test, used to perform the numerical simulations. Despite of a number of introduced errors in the real...... is to divide a structure into a physical substructure and a numerical substructure, and couple these in a test. If the test is conducted in real-time it is referred to as real time hybrid testing. The hybrid testing concept has developed significantly since its introduction in the 1960', both with respect...

  18. RANA, a real-time multi-agent system simulator

    DEFF Research Database (Denmark)

    Jørgensen, Søren Vissing; Demazeau, Yves; Hallam, John

    2016-01-01

    for individualisation and abstraction while retaining efficiency. Events are managed by the C++ simulator core. Full run state can be recorded for post-processed visualisation or analysis. The new tool is demonstrated in three different cases: a mining robot simulation, which is purely action based; an agent......-based setup that is verifies the high precision exhibited by RANAs simulation core; and a state-based firefly-like agent simulation that models real-time responses to fellow agents' signals, in which event propagation and reception affect the result of the simulation....

  19. An Optimization Framework for Dynamic, Distributed Real-Time Systems

    Science.gov (United States)

    Eckert, Klaus; Juedes, David; Welch, Lonnie; Chelberg, David; Bruggerman, Carl; Drews, Frank; Fleeman, David; Parrott, David; Pfarr, Barbara

    2003-01-01

    Abstract. This paper presents a model that is useful for developing resource allocation algorithms for distributed real-time systems .that operate in dynamic environments. Interesting aspects of the model include dynamic environments, utility and service levels, which provide a means for graceful degradation in resource-constrained situations and support optimization of the allocation of resources. The paper also provides an allocation algorithm that illustrates how to use the model for producing feasible, optimal resource allocations.

  20. Real-Time Incompressible Fluid Simulation on the GPU

    Directory of Open Access Journals (Sweden)

    Xiao Nie

    2015-01-01

    Full Text Available We present a parallel framework for simulating incompressible fluids with predictive-corrective incompressible smoothed particle hydrodynamics (PCISPH on the GPU in real time. To this end, we propose an efficient GPU streaming pipeline to map the entire computational task onto the GPU, fully exploiting the massive computational power of state-of-the-art GPUs. In PCISPH-based simulations, neighbor search is the major performance obstacle because this process is performed several times at each time step. To eliminate this bottleneck, an efficient parallel sorting method for this time-consuming step is introduced. Moreover, we discuss several optimization techniques including using fast on-chip shared memory to avoid global memory bandwidth limitations and thus further improve performance on modern GPU hardware. With our framework, the realism of real-time fluid simulation is significantly improved since our method enforces incompressibility constraint which is typically ignored due to efficiency reason in previous GPU-based SPH methods. The performance results illustrate that our approach can efficiently simulate realistic incompressible fluid in real time and results in a speed-up factor of up to 23 on a high-end NVIDIA GPU in comparison to single-threaded CPU-based implementation.

  1. Reflexive reasoning for distributed real-time systems

    Science.gov (United States)

    Goldstein, David

    1994-01-01

    This paper discusses the implementation and use of reflexive reasoning in real-time, distributed knowledge-based applications. Recently there has been a great deal of interest in agent-oriented systems. Implementing such systems implies a mechanism for sharing knowledge, goals and other state information among the agents. Our techniques facilitate an agent examining both state information about other agents and the parameters of the knowledge-based system shell implementing its reasoning algorithms. The shell implementing the reasoning is the Distributed Artificial Intelligence Toolkit, which is a derivative of CLIPS.

  2. A distributed scheduling algorithm for heterogeneous real-time systems

    Science.gov (United States)

    Zeineldine, Osman; El-Toweissy, Mohamed; Mukkamala, Ravi

    1991-01-01

    Much of the previous work on load balancing and scheduling in distributed environments was concerned with homogeneous systems and homogeneous loads. Several of the results indicated that random policies are as effective as other more complex load allocation policies. The effects of heterogeneity on scheduling algorithms for hard real time systems is examined. A distributed scheduler specifically to handle heterogeneities in both nodes and node traffic is proposed. The performance of the algorithm is measured in terms of the percentage of jobs discarded. While a random task allocation is very sensitive to heterogeneities, the algorithm is shown to be robust to such non-uniformities in system components and load.

  3. A Real-Time Simulation Platform for Power System Operation

    DEFF Research Database (Denmark)

    Cha, Seung-Tae; Østergaard, Jacob; Wu, Qiuwei

    2010-01-01

    This paper describes the real-time digital simulation platform that can be used for power system operation, analysis, and power system modeling. This particular platform gives grid operators, planners and researchers the opportunity to observe how a power system behaves and can be used...... in real time. Various phenomena commonly encountered when dealing with the two-area system is studied. Despite its small size, it mimics very closely the behavior of typical systems in actual operation. The electromagnetic transient type of simulation made in RSCAD enables the study of fast and detailed...... phenomena like single-phase faults in the two-area network and to observe their effects on a larger time scale. Also, the case study of 11 bus system with 5 generators has been also used and the results are presented....

  4. Real-time simulation of ex-core nuclear instrumentation system

    International Nuclear Information System (INIS)

    Zhao Qiang; Zhang Zhijian; Cao Xinrong

    2005-01-01

    Real-time simulation of ex-core nuclear instrumentation system is an indispensable part of nuclear power plant (NPP) full-scope training simulator. The simulation method, which is based upon the theory of measurement, is introduced in the paper. The fitting formula between the measured data and the three-dimensional neutron flux distribution in the core is established. The fitting parameter is adjusted according to the reactor physical calculation or the experiment of power calibration. The simulation result shows that the method can simulate the ex-core neutron instrumentation system accurately in real-time and meets the needs of NPP full-scope training simulator. (authors)

  5. Toward real-time regional earthquake simulation of Taiwan earthquakes

    Science.gov (United States)

    Lee, S.; Liu, Q.; Tromp, J.; Komatitsch, D.; Liang, W.; Huang, B.

    2013-12-01

    We developed a Real-time Online earthquake Simulation system (ROS) to simulate regional earthquakes in Taiwan. The ROS uses a centroid moment tensor solution of seismic events from a Real-time Moment Tensor monitoring system (RMT), which provides all the point source parameters including the event origin time, hypocentral location, moment magnitude and focal mechanism within 2 minutes after the occurrence of an earthquake. Then, all of the source parameters are automatically forwarded to the ROS to perform an earthquake simulation, which is based on a spectral-element method (SEM). We have improved SEM mesh quality by introducing a thin high-resolution mesh layer near the surface to accommodate steep and rapidly varying topography. The mesh for the shallow sedimentary basin is adjusted to reflect its complex geometry and sharp lateral velocity contrasts. The grid resolution at the surface is about 545 m, which is sufficient to resolve topography and tomography data for simulations accurate up to 1.0 Hz. The ROS is also an infrastructural service, making online earthquake simulation feasible. Users can conduct their own earthquake simulation by providing a set of source parameters through the ROS webpage. For visualization, a ShakeMovie and ShakeMap are produced during the simulation. The time needed for one event is roughly 3 minutes for a 70 sec ground motion simulation. The ROS is operated online at the Institute of Earth Sciences, Academia Sinica (http://ros.earth.sinica.edu.tw/). Our long-term goal for the ROS system is to contribute to public earth science outreach and to realize seismic ground motion prediction in real-time.

  6. Validation and Assessment of Multi-GNSS Real-Time Precise Point Positioning in Simulated Kinematic Mode Using IGS Real-Time Service

    Directory of Open Access Journals (Sweden)

    Liang Wang

    2018-02-01

    Full Text Available Precise Point Positioning (PPP is a popular technology for precise applications based on the Global Navigation Satellite System (GNSS. Multi-GNSS combined PPP has become a hot topic in recent years with the development of multiple GNSSs. Meanwhile, with the operation of the real-time service (RTS of the International GNSS Service (IGS agency that provides satellite orbit and clock corrections to broadcast ephemeris, it is possible to obtain the real-time precise products of satellite orbits and clocks and to conduct real-time PPP. In this contribution, the real-time multi-GNSS orbit and clock corrections of the CLK93 product are applied for real-time multi-GNSS PPP processing, and its orbit and clock qualities are investigated, first with a seven-day experiment by comparing them with the final multi-GNSS precise product ‘GBM’ from GFZ. Then, an experiment involving real-time PPP processing for three stations in the Multi-GNSS Experiment (MGEX network with a testing period of two weeks is conducted in order to evaluate the convergence performance of real-time PPP in a simulated kinematic mode. The experimental result shows that real-time PPP can achieve a convergence performance of less than 15 min for an accuracy level of 20 cm. Finally, the real-time data streams from 12 globally distributed IGS/MGEX stations for one month are used to assess and validate the positioning accuracy of real-time multi-GNSS PPP. The results show that the simulated kinematic positioning accuracy achieved by real-time PPP on different stations is about 3.0 to 4.0 cm for the horizontal direction and 5.0 to 7.0 cm for the three-dimensional (3D direction.

  7. Numerical simulation of a cabin ventilation subsystem in a space station oriented real-time system

    Directory of Open Access Journals (Sweden)

    Zezheng QIU

    2017-12-01

    Full Text Available An environment control and life support system (ECLSS is an important system in a space station. The ECLSS is a typical complex system, and the real-time simulation technology can help to accelerate its research process by using distributed hardware in a loop simulation system. An implicit fixed time step numerical integration method is recommended for a real-time simulation system with time-varying parameters. However, its computational efficiency is too low to satisfy the real-time data interaction, especially for the complex ECLSS system running on a PC cluster. The instability problem of an explicit method strongly limits its application in the ECLSS real-time simulation although it has a high computational efficiency. This paper proposes an improved numerical simulation method to overcome the instability problem based on the explicit Euler method. A temperature and humidity control subsystem (THCS is firstly established, and its numerical stability is analyzed by using the eigenvalue estimation theory. Furthermore, an adaptive operator is proposed to avoid the potential instability problem. The stability and accuracy of the proposed method are investigated carefully. Simulation results show that this proposed method can provide a good way for some complex time-variant systems to run their real-time simulation on a PC cluster. Keywords: Numerical integration method, Real-time simulation, Stability, THCS, Time-variant system

  8. Simulating Photon Mapping for Real-time Applications

    DEFF Research Database (Denmark)

    Larsen, Bent Dalgaard; Christensen, Niels Jørgen

    2004-01-01

    This paper introduces a novel method for simulating photon mapping for real-time applications. First we introduce a new method for selectively redistributing photons. Then we describe a method for selectively updating the indirect illumination. The indirect illumination is calculated using a new...... GPU accelerated final gathering method and the illumination is then stored in light maps. Caustic photons are traced on the CPU and then drawn using points in the framebuffer, and finally filtered using the GPU. Both diffuse and non-diffuse surfaces can be handled by calculating the direct...... illumination on the GPU and the photon tracing on the CPU. We achieve real-time frame rates for dynamic scenes....

  9. Real-time Executive for a basic principle simulator

    International Nuclear Information System (INIS)

    Buerger, L.; Szegi, Zs.; Vegh, E.

    1987-09-01

    A basic principle simulator for WWER-440 type nuclear power plants is under development in the Central Research Institute for Physics, Budapest. So far the technological models of both to primary and secondary circuits are ready and this paper presents the Real-time Executive and the on-line operating environment which controls the simulator. This executive system contains eight programs and the detailed structure of the data base is presented. The control of the execution of the model programs, their timing and the error recoveries are also discussed. (author) 5 refs

  10. Toward real-time regional earthquake simulation II: Real-time Online earthquake Simulation (ROS) of Taiwan earthquakes

    Science.gov (United States)

    Lee, Shiann-Jong; Liu, Qinya; Tromp, Jeroen; Komatitsch, Dimitri; Liang, Wen-Tzong; Huang, Bor-Shouh

    2014-06-01

    We developed a Real-time Online earthquake Simulation system (ROS) to simulate regional earthquakes in Taiwan. The ROS uses a centroid moment tensor solution of seismic events from a Real-time Moment Tensor monitoring system (RMT), which provides all the point source parameters including the event origin time, hypocentral location, moment magnitude and focal mechanism within 2 min after the occurrence of an earthquake. Then, all of the source parameters are automatically forwarded to the ROS to perform an earthquake simulation, which is based on a spectral-element method (SEM). A new island-wide, high resolution SEM mesh model is developed for the whole Taiwan in this study. We have improved SEM mesh quality by introducing a thin high-resolution mesh layer near the surface to accommodate steep and rapidly varying topography. The mesh for the shallow sedimentary basin is adjusted to reflect its complex geometry and sharp lateral velocity contrasts. The grid resolution at the surface is about 545 m, which is sufficient to resolve topography and tomography data for simulations accurate up to 1.0 Hz. The ROS is also an infrastructural service, making online earthquake simulation feasible. Users can conduct their own earthquake simulation by providing a set of source parameters through the ROS webpage. For visualization, a ShakeMovie and ShakeMap are produced during the simulation. The time needed for one event is roughly 3 min for a 70 s ground motion simulation. The ROS is operated online at the Institute of Earth Sciences, Academia Sinica (http://ros.earth.sinica.edu.tw/). Our long-term goal for the ROS system is to contribute to public earth science outreach and to realize seismic ground motion prediction in real-time.

  11. Real-time maritime scene simulation for ladar sensors

    Science.gov (United States)

    Christie, Chad L.; Gouthas, Efthimios; Swierkowski, Leszek; Williams, Owen M.

    2011-06-01

    Continuing interest exists in the development of cost-effective synthetic environments for testing Laser Detection and Ranging (ladar) sensors. In this paper we describe a PC-based system for real-time ladar scene simulation of ships and small boats in a dynamic maritime environment. In particular, we describe the techniques employed to generate range imagery accompanied by passive radiance imagery. Our ladar scene generation system is an evolutionary extension of the VIRSuite infrared scene simulation program and includes all previous features such as ocean wave simulation, the physically-realistic representation of boat and ship dynamics, wake generation and simulation of whitecaps, spray, wake trails and foam. A terrain simulation extension is also under development. In this paper we outline the development, capabilities and limitations of the VIRSuite extensions.

  12. Real-time dynamic imaging of virus distribution in vivo.

    Directory of Open Access Journals (Sweden)

    Sean E Hofherr

    2011-02-01

    Full Text Available The distribution of viruses and gene therapy vectors is difficult to assess in a living organism. For instance, trafficking in murine models can usually only be assessed after sacrificing the animal for tissue sectioning or extraction. These assays are laborious requiring whole animal sectioning to ascertain tissue localization. They also obviate the ability to perform longitudinal or kinetic studies in one animal. To track viruses after systemic infection, we have labeled adenoviruses with a near-infrared (NIR fluorophore and imaged these after intravenous injection in mice. Imaging was able to track and quantitate virus particles entering the jugular vein simultaneous with injection, appearing in the heart within 500 milliseconds, distributing in the bloodstream and throughout the animal within 7 seconds, and that the bulk of virus distribution was essentially complete within 3 minutes. These data provide the first in vivo real-time tracking of the rapid initial events of systemic virus infection.

  13. Real-time numerical simulation of the Carnot cycle

    International Nuclear Information System (INIS)

    Hurkala, J; Gall, M; Kutner, R; Maciejczyk, M

    2005-01-01

    We developed a highly interactive, multi-windows Java applet which made it possible to simulate and visualize within any platform and internet the Carnot cycle (or engine) in a real-time computer experiment. We extended our previous model and algorithm (Galant et al 2003 Heat Transfer, Newton's Law of Cooling and the Law of Entropy Increase Simulated by the Real-Time Computer Experiments in Java (Lecture Notes in Computer Science vol 2657) pp 45-53, Gall and Kutner 2005 Molecular mechanisms of heat transfer: Debye relaxation versus power-law Physica A 352 347-78) to simulate not only the heat flow but also the macroscopic movement of the piston. Since in reality it is impossible to construct a reversible Carnot engine, the question arises whether it is possible to simulate it at least in a numerical experiment? The positive answer to this question which we found is related to our model and algorithm which make it possible to omit the many-body problem arising when many gas particles simultaneously interact with the mobile piston. As usual, the considerations of phenomenological thermodynamics began with a study of the basic properties of heat engines, hence our approach, besides intrinsic physical significance, is also important from the educational, technological and even environmental points of view

  14. Real-Time Numerical Simulation of the Carnot Cycle

    International Nuclear Information System (INIS)

    Hurkala, J.; Gall, M.; Kutner, R.; Maciejczyk, M.

    2005-01-01

    We developed a highly interactive, multi-windows Java applet which made it possible to simulate and visualize within any platform and internet the Carnot cycle (or engine) in a real-time computer experiment. We extended our previous model and algorithm to simulate not only the heat flow but also the macroscopic movement of the piston. since in reality it is impossible to construct a reversible Carnot engine, the question arises whether it is possible to simulate it at least in a numerical experiment? The positive answer to this question which we found is related to our model and algorithm which make it possible to omit the many-body problem arising when many gas particles simultaneously interact with the mobile piston. As usually the considerations of phenomenomenological thermodynamics began with a study of the basic properties of heat engines hence our approach, beside intrinsic physical significance, is also important from the educational, technological and even environmental points of view. (author)

  15. Blocking Optimality in Distributed Real-Time Locking Protocols

    Directory of Open Access Journals (Sweden)

    Björn Bernhard Brandenburg

    2014-09-01

    Full Text Available Lower and upper bounds on the maximum priority inversion blocking (pi-blocking that is generally unavoidable in distributed multiprocessor real-time locking protocols (where resources may be accessed only from specific synchronization processors are established. Prior work on suspension-based shared-memory multiprocessor locking protocols (which require resources to be accessible from all processors has established asymptotically tight bounds of Ω(m and Ω(n maximum pi-blocking under suspension-oblivious and suspension-aware analysis, respectively, where m denotes the total number of processors and n denotes the number of tasks. In this paper, it is shown that, in the case of distributed semaphore protocols, there exist two different task allocation scenarios that give rise to distinct lower bounds. In the case of co-hosted task allocation, where application tasks may also be assigned to synchronization processors (i.e., processors hosting critical sections, Ω(Φ · n maximum pi-blocking is unavoidable for some tasks under any locking protocol under both suspension-aware and suspension-oblivious schedulability analysis, where Φ denotes the ratio of the maximum response time to the shortest period. In contrast, in the case of disjoint task allocation (i.e., if application tasks may not be assigned to synchronization processors, only Ω(m and Ω(n maximum pi-blocking is fundamentally unavoidable under suspension-oblivious and suspension-aware analysis, respectively, as in the shared-memory case. These bounds are shown to be asymptotically tight with the construction of two new distributed real-time locking protocols that ensure O(m and O(n maximum pi-blocking under suspension-oblivious and suspension-aware analysis, respectively.

  16. Improved real-time dynamics from imaginary frequency lattice simulations

    Directory of Open Access Journals (Sweden)

    Pawlowski Jan M.

    2018-01-01

    Full Text Available The computation of real-time properties, such as transport coefficients or bound state spectra of strongly interacting quantum fields in thermal equilibrium is a pressing matter. Since the sign problem prevents a direct evaluation of these quantities, lattice data needs to be analytically continued from the Euclidean domain of the simulation to Minkowski time, in general an ill-posed inverse problem. Here we report on a novel approach to improve the determination of real-time information in the form of spectral functions by setting up a simulation prescription in imaginary frequencies. By carefully distinguishing between initial conditions and quantum dynamics one obtains access to correlation functions also outside the conventional Matsubara frequencies. In particular the range between ω0 and ω1 = 2πT, which is most relevant for the inverse problem may be more highly resolved. In combination with the fact that in imaginary frequencies the kernel of the inverse problem is not an exponential but only a rational function we observe significant improvements in the reconstruction of spectral functions, demonstrated in a simple 0+1 dimensional scalar field theory toy model.

  17. Improved real-time dynamics from imaginary frequency lattice simulations

    Science.gov (United States)

    Pawlowski, Jan M.; Rothkopf, Alexander

    2018-03-01

    The computation of real-time properties, such as transport coefficients or bound state spectra of strongly interacting quantum fields in thermal equilibrium is a pressing matter. Since the sign problem prevents a direct evaluation of these quantities, lattice data needs to be analytically continued from the Euclidean domain of the simulation to Minkowski time, in general an ill-posed inverse problem. Here we report on a novel approach to improve the determination of real-time information in the form of spectral functions by setting up a simulation prescription in imaginary frequencies. By carefully distinguishing between initial conditions and quantum dynamics one obtains access to correlation functions also outside the conventional Matsubara frequencies. In particular the range between ω0 and ω1 = 2πT, which is most relevant for the inverse problem may be more highly resolved. In combination with the fact that in imaginary frequencies the kernel of the inverse problem is not an exponential but only a rational function we observe significant improvements in the reconstruction of spectral functions, demonstrated in a simple 0+1 dimensional scalar field theory toy model.

  18. Data distribution architecture based on standard real time protocol

    International Nuclear Information System (INIS)

    Castro, R.; Vega, J.; Pereira, A.; Portas, A.

    2009-01-01

    Data distribution architecture (DDAR) has been designed conforming to new requirements, taking into account the type of data that is going to be generated from experiments in International Thermonuclear Experimental Reactor (ITER). The main goal of this architecture is to implement a system that is able to manage on line all data that is being generated by an experiment, supporting its distribution for: processing, storing, analysing or visualizing. The first objective is to have a distribution architecture that supports long pulse experiments (even hours). The described system is able to distribute, using real time protocol (RTP), stored data or live data generated while the experiment is running. It enables researchers to access data on line instead of waiting for the end of the experiment. Other important objective is scalability, so the presented architecture can easily grow based on actual necessities, simplifying estimation and design tasks. A third important objective is security. In this sense, the architecture is based on standards, so complete security mechanisms can be applied, from secure transmission solutions until elaborated access control policies, and it is full compatible with multi-organization federation systems as PAPI or Shibboleth.

  19. Data distribution architecture based on standard real time protocol

    Energy Technology Data Exchange (ETDEWEB)

    Castro, R. [Asociacion EURATOM/CIEMAT para Fusion, Avda. Complutense No. 22, 28040 Madrid (Spain)], E-mail: rodrigo.castro@ciemat.es; Vega, J.; Pereira, A.; Portas, A. [Asociacion EURATOM/CIEMAT para Fusion, Avda. Complutense No. 22, 28040 Madrid (Spain)

    2009-06-15

    Data distribution architecture (DDAR) has been designed conforming to new requirements, taking into account the type of data that is going to be generated from experiments in International Thermonuclear Experimental Reactor (ITER). The main goal of this architecture is to implement a system that is able to manage on line all data that is being generated by an experiment, supporting its distribution for: processing, storing, analysing or visualizing. The first objective is to have a distribution architecture that supports long pulse experiments (even hours). The described system is able to distribute, using real time protocol (RTP), stored data or live data generated while the experiment is running. It enables researchers to access data on line instead of waiting for the end of the experiment. Other important objective is scalability, so the presented architecture can easily grow based on actual necessities, simplifying estimation and design tasks. A third important objective is security. In this sense, the architecture is based on standards, so complete security mechanisms can be applied, from secure transmission solutions until elaborated access control policies, and it is full compatible with multi-organization federation systems as PAPI or Shibboleth.

  20. Progress on RTSS simulation-based analysis for real-time systems development at two laboratories

    International Nuclear Information System (INIS)

    Shu, Y.; Jia, M.; Fei, Y.; Zhang, Y.; Liu, G.; Yang, S.; Chen, Y.

    1996-01-01

    A new object-oriented Real Time System Simulator (RTSS) with the capability for simulation graphics and animation, has been developed and used for modeling the distributed data acquisition and processing systems at JET and ASIPP. Simulation allows estimates of response time, throughput and resource utilization for a variety of configurations to be investigated. Performance measurements, simulation and analysis are used together to calibrate and validate each other

  1. The FERMI-Elettra distributed real-time framework

    International Nuclear Information System (INIS)

    Pivetta, L.; Gaio, G.; Passuello, R.; Scalamera, G.

    2012-01-01

    FERMI-Elettra is a Free Electron Laser (FEL) based on a 1.5 GeV linac. The pulsed operation of the accelerator and the necessity to characterize and control each electron bunch requires synchronous acquisition of the beam diagnostics together with the ability to drive actuators in real-time at the linac repetition rate. The Adeos/Xenomai real-time extensions have been adopted in order to add real-time capabilities to the Linux based control system computers running the Tango software. A software communication protocol based on Gigabit Ethernet and known as Network Reflective Memory (NRM) has been developed to implement a shared memory across the whole control system, allowing computers to communicate in real-time. The NRM architecture, the real-time performance and the integration in the control system are described. (authors)

  2. A distributed agent architecture for real-time knowledge-based systems: Real-time expert systems project, phase 1

    Science.gov (United States)

    Lee, S. Daniel

    1990-01-01

    We propose a distributed agent architecture (DAA) that can support a variety of paradigms based on both traditional real-time computing and artificial intelligence. DAA consists of distributed agents that are classified into two categories: reactive and cognitive. Reactive agents can be implemented directly in Ada to meet hard real-time requirements and be deployed on on-board embedded processors. A traditional real-time computing methodology under consideration is the rate monotonic theory that can guarantee schedulability based on analytical methods. AI techniques under consideration for reactive agents are approximate or anytime reasoning that can be implemented using Bayesian belief networks as in Guardian. Cognitive agents are traditional expert systems that can be implemented in ART-Ada to meet soft real-time requirements. During the initial design of cognitive agents, it is critical to consider the migration path that would allow initial deployment on ground-based workstations with eventual deployment on on-board processors. ART-Ada technology enables this migration while Lisp-based technologies make it difficult if not impossible. In addition to reactive and cognitive agents, a meta-level agent would be needed to coordinate multiple agents and to provide meta-level control.

  3. Real-Time Analysis and Forecasting of Multisite River Flow Using a Distributed Hydrological Model

    Directory of Open Access Journals (Sweden)

    Mingdong Sun

    2014-01-01

    Full Text Available A spatial distributed hydrological forecasting system was developed to promote the analysis of river flow dynamic state in a large basin. The research presented the real-time analysis and forecasting of multisite river flow in the Nakdong River Basin using a distributed hydrological model with radar rainfall forecast data. A real-time calibration algorithm of hydrological distributed model was proposed to investigate the particular relationship between the water storage and basin discharge. Demonstrate the approach of simulating multisite river flow using a distributed hydrological model couple with real-time calibration and forecasting of multisite river flow with radar rainfall forecasts data. The hydrographs and results exhibit that calibrated flow simulations are very approximate to the flow observation at all sites and the accuracy of forecasting flow is gradually decreased with lead times extending from 1 hr to 3 hrs. The flow forecasts are lower than the flow observation which is likely caused by the low estimation of radar rainfall forecasts. The research has well demonstrated that the distributed hydrological model is readily applicable for multisite real-time river flow analysis and forecasting in a large basin.

  4. Distributed energy resources scheduling considering real-time resources forecast

    DEFF Research Database (Denmark)

    Silva, M.; Sousa, T.; Ramos, S.

    2014-01-01

    grids and considering day-ahead, hour-ahead and realtime time horizons. This method considers that energy resources are managed by a VPP which establishes contracts with their owners. The full AC power flow calculation included in the model takes into account network constraints. In this paper......, distribution function errors are used to simulate variations between time horizons, and to measure the performance of the proposed methodology. A 33-bus distribution network with large number of distributed resources is used....

  5. Cybersecurity through Real-Time Distributed Control Systems

    Energy Technology Data Exchange (ETDEWEB)

    Kisner, Roger A [ORNL; Manges, Wayne W [ORNL; MacIntyre, Lawrence Paul [ORNL; Nutaro, James J [ORNL; Munro Jr, John K [ORNL; Ewing, Paul D [ORNL; Howlader, Mostofa [ORNL; Kuruganti, Phani Teja [ORNL; Wallace, Richard M [ORNL; Olama, Mohammed M [ORNL

    2010-04-01

    Critical infrastructure sites and facilities are becoming increasingly dependent on interconnected physical and cyber-based real-time distributed control systems (RTDCSs). A mounting cybersecurity threat results from the nature of these ubiquitous and sometimes unrestrained communications interconnections. Much work is under way in numerous organizations to characterize the cyber threat, determine means to minimize risk, and develop mitigation strategies to address potential consequences. While it seems natural that a simple application of cyber-protection methods derived from corporate business information technology (IT) domain would lead to an acceptable solution, the reality is that the characteristics of RTDCSs make many of those methods inadequate and unsatisfactory or even harmful. A solution lies in developing a defense-in-depth approach that ranges from protection at communications interconnect levels ultimately to the control system s functional characteristics that are designed to maintain control in the face of malicious intrusion. This paper summarizes the nature of RTDCSs from a cybersecurity perspec tive and discusses issues, vulnerabilities, candidate mitigation approaches, and metrics.

  6. Analysis and Synthesis of Distributed Real-Time Embedded Systems

    DEFF Research Database (Denmark)

    Pop, Paul; Eles, Petru; Peng, Zebo

    like automotive electronics, real-time multimedia, avionics, medical equipment, and factory systems. The proposed analysis and synthesis techniques derive optimized implementations that fulfill the imposed design constraints. An important part of the implementation process is the synthesis...

  7. Real-time flight test data distribution and display

    Science.gov (United States)

    Nesel, Michael C.; Hammons, Kevin R.

    1988-01-01

    Enhancements to the real-time processing and display systems of the NASA Western Aeronautical Test Range are described. Display processing has been moved out of the telemetry and radar acquisition processing systems super-minicomputers into user/client interactive graphic workstations. Real-time data is provided to the workstations by way of Ethernet. Future enhancement plans include use of fiber optic cable to replace the Ethernet.

  8. Real-Time Optimization and Control of Next-Generation Distribution

    Science.gov (United States)

    -Generation Distribution Infrastructure Real-Time Optimization and Control of Next-Generation Distribution developing a system-theoretic distribution network management framework that unifies real-time voltage and Infrastructure | Grid Modernization | NREL Real-Time Optimization and Control of Next

  9. Electric space heating scheduling for real-time explicit power control in active distribution networks

    DEFF Research Database (Denmark)

    Costanzo, Giuseppe Tommaso; Bernstein, Andrey; Chamorro, Lorenzo Reyes

    2015-01-01

    This paper presents a systematic approach for abstracting the flexibility of a building space heating system and using it within a composable framework for real-time explicit power control of microgrids and, more in general, active distribution networks. In particular, the proposed approach...... is developed within the context of a previously defined microgrid control framework, called COMMELEC, conceived for the explicit and real-time control of these specific networks. The designed control algorithm is totally independent from the need of a building model and allows exploiting the intrinsic thermal...... inertia for real-time control. The paper first discusses the general approach, then it proves its validity via dedicated simulations performed on specific case study composed by the CIGRE LV microgrid benchmark proposed by the Cigré TF C6.04.02....

  10. Real-time measurements and their effects on state estimation of distribution power system

    DEFF Research Database (Denmark)

    Han, Xue; You, Shi; Thordarson, Fannar

    2013-01-01

    between the estimated values (voltage and injected power) and the measurements are applied to evaluate the accuracy of the estimated grid states. Eventually, some suggestions are provided for the distribution grid operators on placing the real-time meters in the distribution grid.......This paper aims at analyzing the potential value of using different real-time metering and measuring instruments applied in the low voltage distribution networks for state-estimation. An algorithm is presented to evaluate different combinations of metering data using a tailored state estimator....... It is followed by a case study based on the proposed algorithm. A real distribution grid feeder with different types of meters installed either in the cabinets or at the customer side is selected for simulation and analysis. Standard load templates are used to initiate the state estimation. The deviations...

  11. Event Based Simulator for Parallel Computing over the Wide Area Network for Real Time Visualization

    Science.gov (United States)

    Sundararajan, Elankovan; Harwood, Aaron; Kotagiri, Ramamohanarao; Satria Prabuwono, Anton

    As the computational requirement of applications in computational science continues to grow tremendously, the use of computational resources distributed across the Wide Area Network (WAN) becomes advantageous. However, not all applications can be executed over the WAN due to communication overhead that can drastically slowdown the computation. In this paper, we introduce an event based simulator to investigate the performance of parallel algorithms executed over the WAN. The event based simulator known as SIMPAR (SIMulator for PARallel computation), simulates the actual computations and communications involved in parallel computation over the WAN using time stamps. Visualization of real time applications require steady stream of processed data flow for visualization purposes. Hence, SIMPAR may prove to be a valuable tool to investigate types of applications and computing resource requirements to provide uninterrupted flow of processed data for real time visualization purposes. The results obtained from the simulation show concurrence with the expected performance using the L-BSP model.

  12. A distributed real-time Java system based on CSP

    NARCIS (Netherlands)

    Bakkers, André; Hilderink, G.H.; Broenink, Johannes F.

    1999-01-01

    Real-time embedded systems in general require a reliability that is orders of magnitude higher than what is presently obtainable with state of the art C programs. The reason for the poor reliability of present day software is the unavailability of a formalism to design sequential C programs. The use

  13. Scheduling and Communication Synthesis for Distributed Real-Time Systems

    DEFF Research Database (Denmark)

    Pop, Paul

    2000-01-01

    on aspects of scheduling and communication for embedded real-time systems. Special emphasis has been placed on the impact of the communication infrastructure and protocol on the overall system performance. The scheduling and communication strategies proposed are based on an abstract graph representation...

  14. Representing real time semantics for distributed application integration

    NARCIS (Netherlands)

    Poon, P.M.S.; Dillon, T.S.; Chang, E.; Feng, L.

    Traditional real time system design and development are driven by technological requirements. With the ever growing complexity of requirements and the advances in software design, the alignment of focus has gradually been shifted to the perspective of business and industrial needs. This paper

  15. Deepwater Horizon - Estimating surface oil volume distribution in real time

    Science.gov (United States)

    Lehr, B.; Simecek-Beatty, D.; Leifer, I.

    2011-12-01

    Spill responders to the Deepwater Horizon (DWH) oil spill required both the relative spatial distribution and total oil volume of the surface oil. The former was needed on a daily basis to plan and direct local surface recovery and treatment operations. The latter was needed less frequently to provide information for strategic response planning. Unfortunately, the standard spill observation methods were inadequate for an oil spill this size, and new, experimental, methods, were not ready to meet the operational demands of near real-time results. Traditional surface oil estimation tools for large spills include satellite-based sensors to define the spatial extent (but not thickness) of the oil, complemented with trained observers in small aircraft, sometimes supplemented by active or passive remote sensing equipment, to determine surface percent coverage of the 'thick' part of the slick, where the vast majority of the surface oil exists. These tools were also applied to DWH in the early days of the spill but the shear size of the spill prevented synoptic information of the surface slick through the use small aircraft. Also, satellite images of the spill, while large in number, varied considerably in image quality, requiring skilled interpretation of them to identify oil and eliminate false positives. Qualified staff to perform this task were soon in short supply. However, large spills are often events that overcome organizational inertia to the use of new technology. Two prime examples in DWH were the application of hyper-spectral scans from a high-altitude aircraft and more traditional fixed-wing aircraft using multi-spectral scans processed by use of a neural network to determine, respectively, absolute or relative oil thickness. But, with new technology, come new challenges. The hyper-spectral instrument required special viewing conditions that were not present on a daily basis and analysis infrastructure to process the data that was not available at the command

  16. A Distributed Framework for Real Time Path Planning in Practical Multi-agent Systems

    KAUST Repository

    Abdelkader, Mohamed

    2017-10-19

    We present a framework for distributed, energy efficient, and real time implementable algorithms for path planning in multi-agent systems. The proposed framework is presented in the context of a motivating example of capture the flag which is an adversarial game played between two teams of autonomous agents called defenders and attackers. We start with the centralized formulation of the problem as a linear program because of its computational efficiency. Then we present an approximation framework in which each agent solves a local version of the centralized linear program by communicating with its neighbors only. The premise in this work is that for practical multi-agent systems, real time implementability of distributed algorithms is more crucial then global optimality. Thus, instead of verifying the proposed framework by performing offline simulations in MATLAB, we run extensive simulations in a robotic simulator V-REP, which includes a detailed dynamic model of quadrotors. Moreover, to create a realistic scenario, we allow a human operator to control the attacker quadrotor through a joystick in a single attacker setup. These simulations authenticate that the proposed framework is real time implementable and results in a performance that is comparable with the global optimal solution under the considered scenarios.

  17. Towards real-time regional earthquake simulation I: real-time moment tensor monitoring (RMT) for regional events in Taiwan

    Science.gov (United States)

    Lee, Shiann-Jong; Liang, Wen-Tzong; Cheng, Hui-Wen; Tu, Feng-Shan; Ma, Kuo-Fong; Tsuruoka, Hiroshi; Kawakatsu, Hitoshi; Huang, Bor-Shouh; Liu, Chun-Chi

    2014-01-01

    We have developed a real-time moment tensor monitoring system (RMT) which takes advantage of a grid-based moment tensor inversion technique and real-time broad-band seismic recordings to automatically monitor earthquake activities in the vicinity of Taiwan. The centroid moment tensor (CMT) inversion technique and a grid search scheme are applied to obtain the information of earthquake source parameters, including the event origin time, hypocentral location, moment magnitude and focal mechanism. All of these source parameters can be determined simultaneously within 117 s after the occurrence of an earthquake. The monitoring area involves the entire Taiwan Island and the offshore region, which covers the area of 119.3°E to 123.0°E and 21.0°N to 26.0°N, with a depth from 6 to 136 km. A 3-D grid system is implemented in the monitoring area with a uniform horizontal interval of 0.1° and a vertical interval of 10 km. The inversion procedure is based on a 1-D Green's function database calculated by the frequency-wavenumber (fk) method. We compare our results with the Central Weather Bureau (CWB) catalogue data for earthquakes occurred between 2010 and 2012. The average differences between event origin time and hypocentral location are less than 2 s and 10 km, respectively. The focal mechanisms determined by RMT are also comparable with the Broadband Array in Taiwan for Seismology (BATS) CMT solutions. These results indicate that the RMT system is realizable and efficient to monitor local seismic activities. In addition, the time needed to obtain all the point source parameters is reduced substantially compared to routine earthquake reports. By connecting RMT with a real-time online earthquake simulation (ROS) system, all the source parameters will be forwarded to the ROS to make the real-time earthquake simulation feasible. The RMT has operated offline (2010-2011) and online (since January 2012 to present) at the Institute of Earth Sciences (IES), Academia Sinica

  18. a Real-Time GIS Platform for High Sour Gas Leakage Simulation, Evaluation and Visualization

    Science.gov (United States)

    Li, M.; Liu, H.; Yang, C.

    2015-07-01

    The development of high-sulfur gas fields, also known as sour gas field, is faced with a series of safety control and emergency management problems. The GIS-based emergency response system is placed high expectations under the consideration of high pressure, high content, complex terrain and highly density population in Sichuan Basin, southwest China. The most researches on high hydrogen sulphide gas dispersion simulation and evaluation are used for environmental impact assessment (EIA) or emergency preparedness planning. This paper introduces a real-time GIS platform for high-sulfur gas emergency response. Combining with real-time data from the leak detection systems and the meteorological monitoring stations, GIS platform provides the functions of simulating, evaluating and displaying of the different spatial-temporal toxic gas distribution patterns and evaluation results. This paper firstly proposes the architecture of Emergency Response/Management System, secondly explains EPA's Gaussian dispersion model CALPUFF simulation workflow under high complex terrain and real-time data, thirdly explains the emergency workflow and spatial analysis functions of computing the accident influencing areas, population and the optimal evacuation routes. Finally, a well blow scenarios is used for verify the system. The study shows that GIS platform which integrates the real-time data and CALPUFF models will be one of the essential operational platforms for high-sulfur gas fields emergency management.

  19. A Metrics-Based Approach to Intrusion Detection System Evaluation for Distributed Real-Time Systems

    Science.gov (United States)

    2002-04-01

    Based Approach to Intrusion Detection System Evaluation for Distributed Real - Time Systems Authors: G. A. Fink, B. L. Chappell, T. G. Turner, and...Distributed, Security. 1 Introduction Processing and cost requirements are driving future naval combat platforms to use distributed, real - time systems of...distributed, real - time systems . As these systems grow more complex, the timing requirements do not diminish; indeed, they may become more constrained

  20. Real-time Trading Strategies for Proactive Distribution Company with Distributed Generation and Demand Response

    DEFF Research Database (Denmark)

    Wang, Qi

    Distributed energy resources (DERs), such as distributed generation (DG) and demand response (DR), have been recognized worldwide as valuable resources. High integration of DG and DR in the distribution network inspires a potential deregulated environment for the distribution company (DISCO...... in the presented DL market and transact with TL real-time market. A one-leader multi-follower-type bi-level model is proposed to indicate the PDISCO's trading strategies. To participate in the TL real-time market, a methodology is presented to derive continuous bidding/offering strategies for a PDISCO. A bi...

  1. Real-Time-Simulation of IEEE-5-Bus Network on OPAL-RT-OP4510 Simulator

    Science.gov (United States)

    Atul Bhandakkar, Anjali; Mathew, Lini, Dr.

    2018-03-01

    The Real-Time Simulator tools have high computing technologies, improved performance. They are widely used for design and improvement of electrical systems. The advancement of the software tools like MATLAB/SIMULINK with its Real-Time Workshop (RTW) and Real-Time Windows Target (RTWT), real-time simulators are used extensively in many engineering fields, such as industry, education, and research institutions. OPAL-RT-OP4510 is a Real-Time Simulator which is used in both industry and academia. In this paper, the real-time simulation of IEEE-5-Bus network is carried out by means of OPAL-RT-OP4510 with CRO and other hardware. The performance of the network is observed with the introduction of fault at various locations. The waveforms of voltage, current, active and reactive power are observed in the MATLAB simulation environment and on the CRO. Also, Load Flow Analysis (LFA) of IEEE-5-Bus network is computed using MATLAB/Simulink power-gui load flow tool.

  2. Tool set for distributed real-time machine control

    Science.gov (United States)

    Carrott, Andrew J.; Wright, Christopher D.; West, Andrew A.; Harrison, Robert; Weston, Richard H.

    1997-01-01

    Demands for increased control capabilities require next generation manufacturing machines to comprise intelligent building elements, physically located at the point where the control functionality is required. Networks of modular intelligent controllers are increasingly designed into manufacturing machines and usable standards are slowly emerging. To implement a control system using off-the-shelf intelligent devices from multi-vendor sources requires a number of well defined activities, including (a) the specification and selection of interoperable control system components, (b) device independent application programming and (c) device configuration, management, monitoring and control. This paper briefly discusses the support for the above machine lifecycle activities through the development of an integrated computing environment populated with an extendable software toolset. The toolset supports machine builder activities such as initial control logic specification, logic analysis, machine modeling, mechanical verification, application programming, automatic code generation, simulation/test, version control, distributed run-time support and documentation. The environment itself consists of system management tools and a distributed object-oriented database which provides storage for the outputs from machine lifecycle activities and specific target control solutions.

  3. Real Time Emulation of Dynamic Tariff for Congestion Management in Distribution Networks

    DEFF Research Database (Denmark)

    Rasmussen, Theis Bo; Wu, Qiuwei; Huang, Shaojun

    2016-01-01

    This paper presents the real time evaluation of the dynamic tariff (DT) method for alleviating congestion in a distribution networks with high penetration of distributed energy resources (DERs). The DT method is implemented in a real time digital testing platform that emulates a real distribution...

  4. Toward transient finite element simulation of thermal deformation of machine tools in real-time

    Science.gov (United States)

    Naumann, Andreas; Ruprecht, Daniel; Wensch, Joerg

    2018-01-01

    Finite element models without simplifying assumptions can accurately describe the spatial and temporal distribution of heat in machine tools as well as the resulting deformation. In principle, this allows to correct for displacements of the Tool Centre Point and enables high precision manufacturing. However, the computational cost of FE models and restriction to generic algorithms in commercial tools like ANSYS prevents their operational use since simulations have to run faster than real-time. For the case where heat diffusion is slow compared to machine movement, we introduce a tailored implicit-explicit multi-rate time stepping method of higher order based on spectral deferred corrections. Using the open-source FEM library DUNE, we show that fully coupled simulations of the temperature field are possible in real-time for a machine consisting of a stock sliding up and down on rails attached to a stand.

  5. Real-time numerical simulation with high efficiency for an experimental reactor system

    International Nuclear Information System (INIS)

    Ding Shuling; Li Fu; Li Sifeng; Chu Xinyuan

    2006-01-01

    The paper presents a systematic and efficient method for numerical real-time simulation of an experimental reactor. The reactor models were built based on the physical characteristics of the experimental reactor, and several real-time simulation approaches were discussed and compared in the paper. How to implement the real-time reactor simulation system in Windows platform for the sake of hardware-in-loop experiment for the reactor power control system was discussed. (authors)

  6. Analysis of fault tolerance and reliability in distributed real-time system architectures

    International Nuclear Information System (INIS)

    Philippi, Stephan

    2003-01-01

    Safety critical real-time systems are becoming ubiquitous in many areas of our everyday life. Failures of such systems potentially have catastrophic consequences on different scales, in the worst case even the loss of human life. Therefore, safety critical systems have to meet maximum fault tolerance and reliability requirements. As the design of such systems is far from being trivial, this article focuses on concepts to specifically support the early architectural design. In detail, a simulation based approach for the analysis of fault tolerance and reliability in distributed real-time system architectures is presented. With this approach, safety related features can be evaluated in the early development stages and thus prevent costly redesigns in later ones

  7. Implementation of SoC Based Real-Time Electromagnetic Transient Simulator

    Directory of Open Access Journals (Sweden)

    I. Herrera-Leandro

    2017-01-01

    Full Text Available Real-time electromagnetic transient simulators are important tools in the design stage of new control and protection systems for power systems. Real-time simulators are used to test and stress new devices under similar conditions that the device will deal with in a real network with the purpose of finding errors and bugs in the design. The computation of an electromagnetic transient is complex and computationally demanding, due to features such as the speed of the phenomenon, the size of the network, and the presence of time variant and nonlinear elements in the network. In this work, the development of a SoC based real-time and also offline electromagnetic transient simulator is presented. In the design, the required performance is met from two sides, (a using a technique to split the power system into smaller subsystems, which allows parallelizing the algorithm, and (b with specialized and parallel hardware designed to boost the solution flow. The results of this work have shown that for the proposed case studies, based on a balanced distribution of the node of subsystems, the proposed approach has decreased the total simulation time by up to 99 times compared with the classical approach running on a single high performance 32-bit embedded processor ARM-Cortex A9.

  8. Towards Reconfigurable, Separable and Hard Real-Time Hybrid Simulation and Test Systems

    Science.gov (United States)

    Quartier, F.; Delatte, B.; Joubert, M.

    2009-05-01

    Formation flight needs several new technologies, new disciplines, new approaches and above all, more concurrent engineering by more players. One of the problems to be addressed are more complex simulation and test systems that are easy to re-configure to include parts of the target hardware and that can provide sufficient power to handle simulation cores that are requiring one to two orders of magnitude more processing power than the current technology provides. Critical technologies that are already addressed by CNES and Spacebel are study model reuse and simulator reconfigurability (Basiles), model portability (SMP2) and the federation of several simulators using HLA. Two more critical issues are addressed in ongoing R&D work by CNES and Spacebel and are covered by this paper and concern the time engineering and management. The first issue concerns separability (characterisation, identification and handling of separable subsystems) and the consequences on practical systems. Experiments on the Pleiades operational simulator have shown that adding precise simulation of instruments such as Doris and the Star Tracker can be added without significantly impacting overall performance. Improved time analysis leads to better system understanding and testability. The second issue concerns architectures for distributed hybrid simulators systems that provide hard real-time capabilities and can react with a relative time precision and jitter that is in the 10 to 50 µsecond range using mainstream PC's and mainstream Operating Systems. This opens a way to make smaller economic hardware test systems that can be reconfigured to make large hardware test systems without restarting development. Although such systems were considered next to impossible till now, distributed hard real-time systems are getting in reach when modern but mainstream electronics are used and when processor cores can be isolated and reserved for real-time cores. This requires a complete rethinking of the

  9. Software Architecture for Distributed Real-Time Embedded Systems

    National Research Council Canada - National Science Library

    Almeida, Jose

    1998-01-01

    .... This thesis focuses on the distributed scheduling problem. It proposes a distributed scheduling algorithm to allocate and schedule a set of tasks onto a collection of processors linked by a network...

  10. A real-time computer simulation of nuclear simulator software using standard PC hardware and linux environments

    International Nuclear Information System (INIS)

    Cha, K. H.; Kweon, K. C.

    2001-01-01

    A feasibility study, which standard PC hardware and Real-Time Linux are applied to real-time computer simulation of software for a nuclear simulator, is presented in this paper. The feasibility prototype was established with the existing software in the Compact Nuclear Simulator (CNS). Throughout the real-time implementation in the feasibility prototype, we has identified that the approach can enable the computer-based predictive simulation to be approached, due to both the remarkable improvement in real-time performance and the less efforts for real-time implementation under standard PC hardware and Real-Time Linux envrionments

  11. Implementing Run-Time Evaluation of Distributed Timing Constraints in a Real-Time Environment

    DEFF Research Database (Denmark)

    Kristensen, C. H.; Drejer, N.

    1994-01-01

    In this paper we describe a solution to the problem of implementing run-time evaluation of timing constraints in distributed real-time environments......In this paper we describe a solution to the problem of implementing run-time evaluation of timing constraints in distributed real-time environments...

  12. Assessing the benefits of residential demand response in a real time distribution energy market

    International Nuclear Information System (INIS)

    Siano, Pierluigi; Sarno, Debora

    2016-01-01

    Highlights: • A new probabilistic methodology, integrating DR in a distribution energy market is proposed. • The method can alleviate distribution network congestions. • This method based on D-LMPs allows cost savings for end-user customers. • Innovative thermal and shiftable loads Real Time control algorithms are also presented. - Abstract: In the field of electricity distribution networks and with the advent of smart grids and microgrids, the use of Distribution Locational Marginal Price (D-LMPs) in a Real Time (RT) distribution market managed by a Distribution System Operator (DSO) is discussed in presence of empowered residential end-users that are able to bid for energy by a demand aggregator while following Demand Response (DR) initiatives. Each customer is provided by a transactive controller, which reads the locational market signals and answers with a bid taking into account the user preferences about some appliances involved in DR activities and controlled by smart plugs-in. In particular, Heating Ventilation and Air Conditioning (HVAC) appliances and shiftable loads are controlled so that their consumption profile can be modified according to the price of energy. In order to assess the effectiveness of the proposed method in terms of energy and cost saving, an innovative probabilistic methodology for evaluating the impact of residential DR choices considering uncertainties related to load demand, user preferences, environmental conditions, house thermal behavior and wholesale market trends has been proposed. The uncertainties related to the stochastic variations of the variables involved are modeled by using the Monte Carlo Simulation (MCS) method. The combination of MCS and RT distribution market simulation based on D-LMPs are used to assess the operation and impact of the DR method over one month. Simulations results on an 84-buses distribution network confirmed that the proposed method allows saving costs for residential end-users and making

  13. Development and operation of a real-time simulation at the NASA Ames Vertical Motion Simulator

    Science.gov (United States)

    Sweeney, Christopher; Sheppard, Shirin; Chetelat, Monique

    1993-01-01

    The Vertical Motion Simulator (VMS) facility at the NASA Ames Research Center combines the largest vertical motion capability in the world with a flexible real-time operating system allowing research to be conducted quickly and effectively. Due to the diverse nature of the aircraft simulated and the large number of simulations conducted annually, the challenge for the simulation engineer is to develop an accurate real-time simulation in a timely, efficient manner. The SimLab facility and the software tools necessary for an operating simulation will be discussed. Subsequent sections will describe the development process through operation of the simulation; this includes acceptance of the model, validation, integration and production phases.

  14. Resource Optimization in Distributed Real-Time Multimedia Applications

    NARCIS (Netherlands)

    Yang, R.; van der Mei, R.D.; Roubos, D.; Seinstra, F.J.; Bal, H.E.

    2012-01-01

    The research area of multimedia content analysis (MMCA) considers all aspects of the automated extraction of knowledge from multimedia archives and data streams. To adhere to strict time constraints, large-scalemultimedia applications typically are being executed on distributed systems consisting of

  15. Sharing Real-Time Objects in Distributed Embedded Systems

    DEFF Research Database (Denmark)

    Larsen, Erland Ketil; Havn, Ib

    2015-01-01

    microcontrollers connected by a RS-485 bus. The demo system shows that it is relatively simple to implement a distributed embedded system with the provided API, and the latency of the communication service is predictable. A low coupling to hardware makes it easy to port to another platform and/or another network...

  16. Issues in visual support to real-time space system simulation solved in the Systems Engineering Simulator

    Science.gov (United States)

    Yuen, Vincent K.

    1989-01-01

    The Systems Engineering Simulator has addressed the major issues in providing visual data to its real-time man-in-the-loop simulations. Out-the-window views and CCTV views are provided by three scene systems to give the astronauts their real-world views. To expand the window coverage for the Space Station Freedom workstation a rotating optics system is used to provide the widest field of view possible. To provide video signals to as many viewpoints as possible, windows and CCTVs, with a limited amount of hardware, a video distribution system has been developed to time-share the video channels among viewpoints at the selection of the simulation users. These solutions have provided the visual simulation facility for real-time man-in-the-loop simulations for the NASA space program.

  17. Decentralized real-time simulation of forest machines

    Science.gov (United States)

    Freund, Eckhard; Adam, Frank; Hoffmann, Katharina; Rossmann, Juergen; Kraemer, Michael; Schluse, Michael

    2000-10-01

    To develop realistic forest machine simulators is a demanding task. A useful simulator has to provide a close- to-reality simulation of the forest environment as well as the simulation of the physics of the vehicle. Customers demand a highly realistic three dimensional forestry landscape and the realistic simulation of the complex motion of the vehicle even in rough terrain in order to be able to use the simulator for operator training under close-to- reality conditions. The realistic simulation of the vehicle, especially with the driver's seat mounted on a motion platform, greatly improves the effect of immersion into the virtual reality of a simulated forest and the achievable level of education of the driver. Thus, the connection of the real control devices of forest machines to the simulation system has to be supported, i.e. the real control devices like the joysticks or the board computer system to control the crane, the aggregate etc. Beyond, the fusion of the board computer system and the simulation system is realized by means of sensors, i.e. digital and analog signals. The decentralized system structure allows several virtual reality systems to evaluate and visualize the information of the control devices and the sensors. So, while the driver is practicing, the instructor can immerse into the same virtual forest to monitor the session from his own viewpoint. In this paper, we are describing the realized structure as well as the necessary software and hardware components and application experiences.

  18. Real-time definition of non-randomness in the distribution of genomic events.

    Directory of Open Access Journals (Sweden)

    Ulrich Abel

    Full Text Available Features such as mutations or structural characteristics can be non-randomly or non-uniformly distributed within a genome. So far, computer simulations were required for statistical inferences on the distribution of sequence motifs. Here, we show that these analyses are possible using an analytical, mathematical approach. For the assessment of non-randomness, our calculations only require information including genome size, number of (sampled sequence motifs and distance parameters. We have developed computer programs evaluating our analytical formulas for the real-time determination of expected values and p-values. This approach permits a flexible cluster definition that can be applied to most effectively identify non-random or non-uniform sequence motif distribution. As an example, we show the effectivity and reliability of our mathematical approach in clinical retroviral vector integration site distribution.

  19. Real - time Dynamic Simulation and Prediction of Groundwater in Typical Arid Area Based on SPASS Improvement

    Science.gov (United States)

    Wang, Xiao-ming

    2018-03-01

    The establishment of traditional groundwater numerical simulation model, parameter identification and inspection process, especially the water level fitting and the actual observation of the value obtained compared to a large error. Based on the SPASS software, a large number of statistical analysis of the numerical simulation results show that the complexity of the terrain in the study area, the distribution of lithology and the influence of the parameters on the groundwater level in the study area have great influence on the groundwater level. Through the multi-factor analysis and adjustment, the simulated groundwater flow and the actual observation are similar. Then, the final result is taken as the standard value, and the groundwater in the study area is simulated and predicted in real time. The simulation results provide technical support for the further development and utilization of the local water resources.

  20. MicROS-drt: supporting real-time and scalable data distribution in distributed robotic systems.

    Science.gov (United States)

    Ding, Bo; Wang, Huaimin; Fan, Zedong; Zhang, Pengfei; Liu, Hui

    A primary requirement in distributed robotic software systems is the dissemination of data to all interested collaborative entities in a timely and scalable manner. However, providing such a service in a highly dynamic and resource-limited robotic environment is a challenging task, and existing robot software infrastructure has limitations in this aspect. This paper presents a novel robot software infrastructure, micROS-drt, which supports real-time and scalable data distribution. The solution is based on a loosely coupled data publish-subscribe model with the ability to support various time-related constraints. And to realize this model, a mature data distribution standard, the data distribution service for real-time systems (DDS), is adopted as the foundation of the transport layer of this software infrastructure. By elaborately adapting and encapsulating the capability of the underlying DDS middleware, micROS-drt can meet the requirement of real-time and scalable data distribution in distributed robotic systems. Evaluation results in terms of scalability, latency jitter and transport priority as well as the experiment on real robots validate the effectiveness of this work.

  1. Storm blueprints patterns for distributed real-time computation

    CERN Document Server

    Goetz, P Taylor

    2014-01-01

    A blueprints book with 10 different projects built in 10 different chapters which demonstrate the various use cases of storm for both beginner and intermediate users, grounded in real-world example applications.Although the book focuses primarily on Java development with Storm, the patterns are more broadly applicable and the tips, techniques, and approaches described in the book apply to architects, developers, and operations.Additionally, the book should provoke and inspire applications of distributed computing to other industries and domains. Hadoop enthusiasts will also find this book a go

  2. Load sharing in distributed real-time systems with state-change broadcasts

    Science.gov (United States)

    Shin, Kang G.; Chang, Yi-Chieh

    1989-01-01

    A decentralized dynamic load-sharing (LS) method based on state-change broadcasts is proposed for a distributed real-time system. Whenever the state of a node changes from underloaded to fully loaded and vice versa, the node broadcasts this change to a set of nodes, called a buddy set, in the system. The performance of the method is evaluated with both analytic modeling and simulation. It is modeled first by an embedded Markov chain for which numerical solutions are derived. The model solutions are then used to calculate the distribution of queue lengths at the nodes and the probability of meeting task deadlines. The analytical results show that buddy sets of 10 nodes outperform those of less than 10 nodes, and the incremental benefit gained from increasing the buddy set size beyond 15 nodes is insignificant. These and other analytical results are verified by simulation. The proposed LS method is shown to meet task deadlines with a very high probability.

  3. Real-time model for simulating a tracked vehicle on deformable soils

    Directory of Open Access Journals (Sweden)

    Martin Meywerk

    2016-05-01

    Full Text Available Simulation is one possibility to gain insight into the behaviour of tracked vehicles on deformable soils. A lot of publications are known on this topic, but most of the simulations described there cannot be run in real-time. The ability to run a simulation in real-time is necessary for driving simulators. This article describes an approach for real-time simulation of a tracked vehicle on deformable soils. The components of the real-time model are as follows: a conventional wheeled vehicle simulated in the Multi Body System software TRUCKSim, a geometric description of landscape, a track model and an interaction model between track and deformable soils based on Bekker theory and Janosi–Hanamoto, on one hand, and between track and vehicle wheels, on the other hand. Landscape, track model, soil model and the interaction are implemented in MATLAB/Simulink. The details of the real-time model are described in this article, and a detailed description of the Multi Body System part is omitted. Simulations with the real-time model are compared to measurements and to a detailed Multi Body System–finite element method model of a tracked vehicle. An application of the real-time model in a driving simulator is presented, in which 13 drivers assess the comfort of a passive and an active suspension of a tracked vehicle.

  4. Real time simulation of large systems on mini-computer

    International Nuclear Information System (INIS)

    Nakhle, Michel; Roux, Pierre.

    1979-01-01

    Most simulation languages will only accept an explicit formulation of differential equations, and logical variables hold no special status therein. The pace of the suggested methods of integration is limited by the smallest time constant of the model submitted. The NEPTUNIX 2 simulation software has a language that will take implicit equations and an integration method of which the variable pace is not limited by the time constants of the model. This, together with high time and memory ressources optimization of the code generated, makes NEPTUNIX 2 a basic tool for simulation on mini-computers. Since the logical variables are specific entities under centralized control, correct processing of discontinuities and synchronization with a real process are feasible. The NEPTUNIX 2 is the industrial version of NEPTUNIX 1 [fr

  5. Innovative real time simulation training and nuclear probabilistic risk assessment

    International Nuclear Information System (INIS)

    Reisinger, M.F.

    1991-01-01

    Operator errors have been an area of public concern for the safe operation of nuclear power plants since the TMI2 incident. Simply stated, nuclear plants are very complex systems and the public is skeptical of the operators' ability to comprehend and deal with the vast indications and complexities of potential nuclear power plant events. Prior to the TMI2 incident, operator errors and human factors were not included as contributing factors in the Probabilistic Risk Assessment (PRA) studies of nuclear power plant accidents. More recent efforts in nuclear risk assessment have addressed some of the human factors affecting safe nuclear plant operations. One study found four major factors having significant impact on operator effectiveness. This paper discusses human factor PRAs, new applications in simulation training and the specific potential benefits from simulation in promoting safer operation of future power plants as well as current operating power plants

  6. Realistic soft tissue deformation strategies for real time surgery simulation.

    Science.gov (United States)

    Shen, Yunhe; Zhou, Xiangmin; Zhang, Nan; Tamma, Kumar; Sweet, Robert

    2008-01-01

    A volume-preserving deformation method (VPDM) is developed in complement with the mass-spring method (MSM) to improve the deformation quality of the MSM to model soft tissue in surgical simulation. This method can also be implemented as a stand-alone model. The proposed VPDM satisfies the Newton's laws of motion by obtaining the resultant vectors form an equilibrium condition. The proposed method has been tested in virtual surgery systems with haptic rendering demands.

  7. Real time modeling, simulation and control of dynamical systems

    CERN Document Server

    Mughal, Asif Mahmood

    2016-01-01

    This book introduces modeling and simulation of linear time invariant systems and demonstrates how these translate to systems engineering, mechatronics engineering, and biomedical engineering. It is organized into nine chapters that follow the lectures used for a one-semester course on this topic, making it appropriate for students as well as researchers. The author discusses state space modeling derived from two modeling techniques and the analysis of the system and usage of modeling in control systems design. It also contains a unique chapter on multidisciplinary energy systems with a special focus on bioengineering systems and expands upon how the bond graph augments research in biomedical and bio-mechatronics systems.

  8. On Modelling Real-time and Security properties of Distributed Systems

    NARCIS (Netherlands)

    Corin, Ricardo; Etalle, Sandro; Hartel, Pieter H.; Mader, Angelika H.

    2003-01-01

    We discuss a simplified version of the timing attack to illustrate a connection between security and real-time properties of distributed systems. We suggest several avenues for further research on this and similar connections.

  9. A Real-Time Fault Management Software System for Distributed Environments, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — DyMA-FM (Dynamic Multivariate Assessment for Fault Management) is a software architecture for real-time fault management. Designed to run in a distributed...

  10. Providing Survivable Real-Time Communication Service for Distributed Mission Critical Systems

    National Research Council Canada - National Science Library

    Zhao, Wei; Bettati, Riccardo; Vaidya, Nitin

    2005-01-01

    This document is the final report for Providing Survivable Real-Time Communication Service for Distributed Mission Critical Systems, a Texas A AND M project funded through the DARPA Fault Tolerant Networks Program...

  11. An Environment for Incremental Development of Distributed Extensible Asynchronous Real-time Systems

    Science.gov (United States)

    Ames, Charles K.; Burleigh, Scott; Briggs, Hugh C.; Auernheimer, Brent

    1996-01-01

    Incremental parallel development of distributed real-time systems is difficult. Architectural techniques and software tools developed at the Jet Propulsion Laboratory's (JPL's) Flight System Testbed make feasible the integration of complex systems in various stages of development.

  12. Towards Real-Time Distributed Planning in Multi-Robot Systems

    KAUST Repository

    Abdelkader, Mohamed

    2018-01-01

    of extensive information exchange (communication). The extensive communication between robots can result in decision delays because of which distributed architecture is often impractical for systems with strict real-time constraints, e.g. when decisions have

  13. A Distributed Framework for Real Time Path Planning in Practical Multi-agent Systems

    KAUST Repository

    Abdelkader, Mohamed; Jaleel, Hassan; Shamma, Jeff S.

    2017-01-01

    We present a framework for distributed, energy efficient, and real time implementable algorithms for path planning in multi-agent systems. The proposed framework is presented in the context of a motivating example of capture the flag which

  14. Optimization of Time-Partitions for Mixed-Criticality Real-Time Distributed Embedded Systems

    DEFF Research Database (Denmark)

    Tamas-Selicean, Domitian; Pop, Paul

    2011-01-01

    In this paper we are interested in mixed-criticality embedded real-time applications mapped on distributed heterogeneous architectures. The architecture provides both spatial and temporal partitioning, thus enforcing enough separation for the critical applications. With temporal partitioning, each...

  15. Real-time Global Illumination by Simulating Photon Mapping

    DEFF Research Database (Denmark)

    Larsen, Bent Dalgaard

    2004-01-01

    This thesis introduces a new method for simulating photon mapping in realtime. The method uses a variety of both CPU and GPU based algorithms for speeding up the different elements in global illumination. The idea behind the method is to calculate each illumination element individually in a progr......This thesis introduces a new method for simulating photon mapping in realtime. The method uses a variety of both CPU and GPU based algorithms for speeding up the different elements in global illumination. The idea behind the method is to calculate each illumination element individually...... in a progressive and efficient manner. This has been done by analyzing the photon mapping method and by selecting efficient methods, either CPU based or GPU based, which replaces the original photon mapping algorithms. We have chosen to focus on the indirect illumination and the caustics. In our method we first...... divide the photon map into several photon maps in order to make local updates possible. Then indirect illumination is added using light maps that are selectively updated by using selective photon tracing on the CPU. The final gathering step is calculated by using fragment programs and GPU based...

  16. Inverse Flush Air Data System (FADS) for Real Time Simulations

    Science.gov (United States)

    Madhavanpillai, Jayakumar; Dhoaya, Jayanta; Balakrishnan, Vidya Saraswathi; Narayanan, Remesh; Chacko, Finitha Kallely; Narayanan, Shyam Mohan

    2017-12-01

    Flush Air Data Sensing System (FADS) forms a mission critical sub system in future reentry vehicles. FADS makes use of surface pressure measurements from the nose cap of the vehicle for deriving the air data parameters of the vehicle such as angle of attack, angle of sideslip, Mach number, etc. These parameters find use in the flight control and guidance systems, and also assist in the overall mission management. The FADS under consideration in this paper makes use of nine pressure ports located in the nose cap of a technology demonstrator vehicle. In flight, the air data parameters are obtained from the FADS estimation algorithm using the pressure data at the nine pressure ports. But, these pressure data will not be available, for testing the FADS package during ground simulation. So, an inverse software to FADS which estimates the pressure data at the pressure ports for a given flight condition is developed. These pressure data at the nine ports will go as input to the FADS package during ground simulation. The software is run to generate the pressure data for the descent phase trajectory of the technology demonstrator. This data is used again to generate the air data parameters from FADS algorithm. The computed results from FADS algorithm match well with the trajectory data.

  17. LOGIC SIMULATION OF LIFE SUPPORT SYSTEM COMPONENT IN REAL TIME

    Directory of Open Access Journals (Sweden)

    A. S. Marchenko

    2016-01-01

    Full Text Available Abstract. The article proposed the use of simulation methods for evaluating the effectiveness of a stepped fan engine speed control while maintaining the air flow volume in the set boundaries of the «fan-filter» system. A detailed algorithm of the program made on the basis of an Any Logic software package. Is analyzed the possibility of using the proposed method in the design of ventilation systems.The proposed method allows at the design stage to determine the maximum replacement intervals of the systems filter elements, as well as to predict the time to switch the fan motor speeds. Using of the technique allows to refuse the complex air flow systems and maximize the life of the filter elements set.Methods of logical processes modeling allows to reduce construction costs and improve energy efficiency of buildings. 

  18. [Dynamic road vehicle emission inventory simulation study based on real time traffic information].

    Science.gov (United States)

    Huang, Cheng; Liu, Juan; Chen, Chang-Hong; Zhang, Jian; Liu, Deng-Guo; Zhu, Jing-Yu; Huang, Wei-Ming; Chao, Yuan

    2012-11-01

    The vehicle activity survey, including traffic flow distribution, driving condition, and vehicle technologies, were conducted in Shanghai. The databases of vehicle flow, VSP distribution and vehicle categories were established according to the surveyed data. Based on this, a dynamic vehicle emission inventory simulation method was designed by using the real time traffic information data, such as traffic flow and average speed. Some roads in Shanghai city were selected to conduct the hourly vehicle emission simulation as a case study. The survey results show that light duty passenger car and taxi are major vehicles on the roads of Shanghai city, accounting for 48% - 72% and 15% - 43% of the total flow in each hour, respectively. VSP distribution has a good relationship with the average speed. The peak of VSP distribution tends to move to high load section and become lower with the increase of average speed. Vehicles achieved Euro 2 and Euro 3 standards are majorities of current vehicle population in Shanghai. Based on the calibration of vehicle travel mileage data, the proportions of Euro 2 and Euro 3 standard vehicles take up 11% - 70% and 17% - 51% in the real-world situation, respectively. The emission simulation results indicate that the ratios of emission peak and valley for the pollutants of CO, VOC, NO(x) and PM are 3.7, 4.6, 9.6 and 19.8, respectively. CO and VOC emissions mainly come from light-duty passenger car and taxi, which has a good relationship with the traffic flow. NO(x) and PM emissions are mainly from heavy-duty bus and public buses and mainly concentrate in the morning and evening peak hours. The established dynamic vehicle emission simulation method can reflect the change of actual road emission and output high emission road sectors and hours in real time. The method can provide an important technical means and decision-making basis for transportation environment management.

  19. Real - time Optimization of Distributed Energy Storage System Operation Strategy Based on Peak Load Shifting

    Science.gov (United States)

    Wang, Qian; Lu, Guangqi; Li, Xiaoyu; Zhang, Yichi; Yun, Zejian; Bian, Di

    2018-01-01

    To take advantage of the energy storage system (ESS) sufficiently, the factors that the service life of the distributed energy storage system (DESS) and the load should be considered when establishing optimization model. To reduce the complexity of the load shifting of DESS in the solution procedure, the loss coefficient and the equal capacity ratio distribution principle were adopted in this paper. Firstly, the model was established considering the constraint conditions of the cycles, depth, power of the charge-discharge of the ESS, the typical daily load curves, as well. Then, dynamic programming method was used to real-time solve the model in which the difference of power Δs, the real-time revised energy storage capacity Sk and the permission error of depth of charge-discharge were introduced to optimize the solution process. The simulation results show that the optimized results was achieved when the load shifting in the load variance was not considered which means the charge-discharge of the energy storage system was not executed. In the meantime, the service life of the ESS would increase.

  20. Design Of Real-Time Implementable Distributed Suboptimal Control: An LQR Perspective

    KAUST Repository

    Jaleel, Hassan

    2017-09-29

    We propose a framework for multiagent systems in which the agents compute their control actions in real time, based on local information only. The novelty of the proposed framework is that the process of computing a suboptimal control action is divided into two phases: an offline phase and an online phase. In the offline phase, an approximate problem is formulated with a cost function that is close to the optimal cost in some sense and is distributed, i.e., the costs of non-neighboring nodes are not coupled. This phase is centralized and is completed before the deployment of the system. In the online phase, the approximate problem is solved in real time by implementing any efficient distributed optimization algorithm. To quantify the performance loss, we derive upper bounds for the maximum error between the optimal performance and the performance under the proposed framework. Finally, the proposed framework is applied to an example setup in which a team of mobile nodes is assigned the task of establishing a communication link between two base stations with minimum energy consumption. We show through simulations that the performance under the proposed framework is close to the optimal performance and the suboptimal policy can be efficiently implemented online.

  1. A nodalization study of steam separator in real time simulation

    International Nuclear Information System (INIS)

    Horugshyang, Lein; Luh, R.T.J.; Zen-Yow, Wang

    1999-01-01

    The motive of this paper is to investigate the influence of steam separator nodalization on reactor thermohydraulics in terms of stability and level response. Three different nodalizations of steam separator are studied by using THEATRE and REMARK Code in a BWR simulator. The first nodalization is the traditional one with two nodes for steam separator. In this nodalization, the steam separation is modeled in the outer node, i.e., upper downcomer. Separated steam enters the Steen dome node and the liquid goes to the feedwater node. The second nodalization is similar to the first one with the steam separation modeled in the inner node. There is one additional junction connecting steam dome node and the inner node. The liquid fallback junction connects the inner node and feedwater node. The third nodalization is a combination of the former two with an integrated node for steam separator. Boundary conditions in this study are provided by a simplified feedwater and main steam driver. For comparison purpose, three tests including full power steady state initialisation, recirculation pumps runback and reactor scram are conducted. Major parameters such as reactor pressure, reactor level, void fractions, neutronic power and junction flows are recorded for analysis. Test results clearly show that the first nodalization is stable for steady state initialisation. However it has too responsive level performance in core flow reduction transients. The second nodalization is the closest representation of real plant structure, but not the performance. Test results show that an instability occurs in the separator region for both steady state initialisation and transients. This instability is caused by an unbalanced momentum in the dual loop configuration. The magnitude of the oscillation reduces as the power decreases. No superiority to the other nodalizations is shown in the test results. The third nodalization shows both stability and responsiveness in the tests. (author)

  2. Real time testing of intelligent relays for synchronous distributed generation islanding detection

    Science.gov (United States)

    Zhuang, Davy

    As electric power systems continue to grow to meet ever-increasing energy demand, their security, reliability, and sustainability requirements also become more stringent. The deployment of distributed energy resources (DER), including generation and storage, in conventional passive distribution feeders, gives rise to integration problems involving protection and unintentional islanding. Distributed generators need to be islanded for safety reasons when disconnected or isolated from the main feeder as distributed generator islanding may create hazards to utility and third-party personnel, and possibly damage the distribution system infrastructure, including the distributed generators. This thesis compares several key performance indicators of a newly developed intelligent islanding detection relay, against islanding detection devices currently used by the industry. The intelligent relay employs multivariable analysis and data mining methods to arrive at decision trees that contain both the protection handles and the settings. A test methodology is developed to assess the performance of these intelligent relays on a real time simulation environment using a generic model based on a real-life distribution feeder. The methodology demonstrates the applicability and potential advantages of the intelligent relay, by running a large number of tests, reflecting a multitude of system operating conditions. The testing indicates that the intelligent relay often outperforms frequency, voltage and rate of change of frequency relays currently used for islanding detection, while respecting the islanding detection time constraints imposed by standing distributed generator interconnection guidelines.

  3. Real-time tumor ablation simulation based on the dynamic mode decomposition method

    KAUST Repository

    Bourantas, George C.; Ghommem, Mehdi; Kagadis, George C.; Katsanos, Konstantinos H.; Loukopoulos, Vassilios C.; Burganos, Vasilis N.; Nikiforidis, George C.

    2014-01-01

    Purpose: The dynamic mode decomposition (DMD) method is used to provide a reliable forecasting of tumor ablation treatment simulation in real time, which is quite needed in medical practice. To achieve this, an extended Pennes bioheat model must

  4. Interactive real-time nuclear plant simulations on a UNIX based supercomputer

    International Nuclear Information System (INIS)

    Behling, S.R.

    1990-01-01

    Interactive real-time nuclear plant simulations are critically important to train nuclear power plant engineers and operators. In addition, real-time simulations can be used to test the validity and timing of plant technical specifications and operational procedures. To accurately and confidently simulate a nuclear power plant transient in real-time, sufficient computer resources must be available. Since some important transients cannot be simulated using preprogrammed responses or non-physical models, commonly used simulation techniques may not be adequate. However, the power of a supercomputer allows one to accurately calculate the behavior of nuclear power plants even during very complex transients. Many of these transients can be calculated in real-time or quicker on the fastest supercomputers. The concept of running interactive real-time nuclear power plant transients on a supercomputer has been tested. This paper describes the architecture of the simulation program, the techniques used to establish real-time synchronization, and other issues related to the use of supercomputers in a new and potentially very important area. (author)

  5. Towards Real-Time Distributed Planning in Multi-Robot Systems

    KAUST Repository

    Abdelkader, Mohamed

    2018-04-01

    Recently, there has been an increasing interest in robotics related to multi-robot applications. Such systems can be involved in several tasks such as collaborative search and rescue, aerial transportation, surveillance, and monitoring, to name a few. There are two possible architectures for the autonomous control of multi-robot systems. In the centralized architecture, a master controller communicates with all the robots to collect information. It uses this information to make decisions for the entire system and then sends commands to each robot. In contrast, in the distributed architecture, each robot makes its own decision independent from a central authority. While distributed architecture is a more portable solution, it comes at the expense of extensive information exchange (communication). The extensive communication between robots can result in decision delays because of which distributed architecture is often impractical for systems with strict real-time constraints, e.g. when decisions have to be taken in the order of milliseconds. In this thesis, we propose a distributed framework that strikes a balance between limited communicated information and reasonable system-wide performance while running in real-time. We implement the proposed approach in a game setting of two competing teams of drones, defenders and attackers. Defending drones execute a proposed linear program algorithm (using only onboard computing modules) to obstruct attackers from infiltrating a defense zone while having minimal local message passing. Another main contribution is that we developed a realistic simulation environment as well as lab and outdoor hardware setups of customized drones for testing the system in realistic scenarios. Our software is completely open-source and fully integrated with the well-known Robot Operating System (ROS) in hopes to make our work easily reproducible and for rapid future improvements.

  6. Real-time distributed scheduling algorithm for supporting QoS over WDM networks

    Science.gov (United States)

    Kam, Anthony C.; Siu, Kai-Yeung

    1998-10-01

    Most existing or proposed WDM networks employ circuit switching, typically with one session having exclusive use of one entire wavelength. Consequently they are not suitable for data applications involving bursty traffic patterns. The MIT AON Consortium has developed an all-optical LAN/MAN testbed which provides time-slotted WDM service and employs fast-tunable transceivers in each optical terminal. In this paper, we explore extensions of this service to achieve fine-grained statistical multiplexing with different virtual circuits time-sharing the wavelengths in a fair manner. In particular, we develop a real-time distributed protocol for best-effort traffic over this time-slotted WDM service with near-optical fairness and throughput characteristics. As an additional design feature, our protocol supports the allocation of guaranteed bandwidths to selected connections. This feature acts as a first step towards supporting integrated services and quality-of-service guarantees over WDM networks. To achieve high throughput, our approach is based on scheduling transmissions, as opposed to collision- based schemes. Our distributed protocol involves one MAN scheduler and several LAN schedulers (one per LAN) in a master-slave arrangement. Because of propagation delays and limits on control channel capacities, all schedulers are designed to work with partial, delayed traffic information. Our distributed protocol is of the `greedy' type to ensure fast execution in real-time in response to dynamic traffic changes. It employs a hybrid form of rate and credit control for resource allocation. We have performed extensive simulations, which show that our protocol allocates resources (transmitters, receivers, wavelengths) fairly with high throughput, and supports bandwidth guarantees.

  7. Math modeling and computer mechanization for real time simulation of rotary-wing aircraft

    Science.gov (United States)

    Howe, R. M.

    1979-01-01

    Mathematical modeling and computer mechanization for real time simulation of rotary wing aircraft is discussed. Error analysis in the digital simulation of dynamic systems, such as rotary wing aircraft is described. The method for digital simulation of nonlinearities with discontinuities, such as exist in typical flight control systems and rotor blade hinges, is discussed.

  8. Real-time simulation of a Doubly-Fed Induction Generator based wind power system on eMEGASimRTM Real-Time Digital Simulator

    Science.gov (United States)

    Boakye-Boateng, Nasir Abdulai

    The growing demand for wind power integration into the generation mix prompts the need to subject these systems to stringent performance requirements. This study sought to identify the required tools and procedures needed to perform real-time simulation studies of Doubly-Fed Induction Generator (DFIG) based wind generation systems as basis for performing more practical tests of reliability and performance for both grid-connected and islanded wind generation systems. The author focused on developing a platform for wind generation studies and in addition, the author tested the performance of two DFIG models on the platform real-time simulation model; an average SimpowerSystemsRTM DFIG wind turbine, and a detailed DFIG based wind turbine using ARTEMiSRTM components. The platform model implemented here consists of a high voltage transmission system with four integrated wind farm models consisting in total of 65 DFIG based wind turbines and it was developed and tested on OPAL-RT's eMEGASimRTM Real-Time Digital Simulator.

  9. Real time hardware-in-loop simulation of ESMO satellite attitude control system

    Directory of Open Access Journals (Sweden)

    Rune Finnset

    2006-04-01

    Full Text Available This paper studies attitude control of the ESMO satellite using six reaction thrusters. Bang-bang control with dead-zone and Pulse-Width Modulation (PWM for the modulation of the on-time of the thrusters are treated. Closed loop hardware-in-loop simulations, using themicrocontroller unit (MCU Microchip PIC18F452 for implementation of attitude control and MatLab in a standard PC for simulating satellite dynamics, are carried out. Results for real time simulation are compared with autonomous simulations. The controller gives a satisfactory performance in the real time environment.

  10. Operating system for a real-time multiprocessor propulsion system simulator. User's manual

    Science.gov (United States)

    Cole, G. L.

    1985-01-01

    The NASA Lewis Research Center is developing and evaluating experimental hardware and software systems to help meet future needs for real-time, high-fidelity simulations of air-breathing propulsion systems. Specifically, the real-time multiprocessor simulator project focuses on the use of multiple microprocessors to achieve the required computing speed and accuracy at relatively low cost. Operating systems for such hardware configurations are generally not available. A real time multiprocessor operating system (RTMPOS) that supports a variety of multiprocessor configurations was developed at Lewis. With some modification, RTMPOS can also support various microprocessors. RTMPOS, by means of menus and prompts, provides the user with a versatile, user-friendly environment for interactively loading, running, and obtaining results from a multiprocessor-based simulator. The menu functions are described and an example simulation session is included to demonstrate the steps required to go from the simulation loading phase to the execution phase.

  11. Platform for real-time simulation of dynamic systems and hardware-in-the-loop for control algorithms.

    Science.gov (United States)

    de Souza, Isaac D T; Silva, Sergio N; Teles, Rafael M; Fernandes, Marcelo A C

    2014-10-15

    The development of new embedded algorithms for automation and control of industrial equipment usually requires the use of real-time testing. However, the equipment required is often expensive, which means that such tests are often not viable. The objective of this work was therefore to develop an embedded platform for the distributed real-time simulation of dynamic systems. This platform, called the Real-Time Simulator for Dynamic Systems (RTSDS), could be applied in both industrial and academic environments. In industrial applications, the RTSDS could be used to optimize embedded control algorithms. In the academic sphere, it could be used to support research into new embedded solutions for automation and control and could also be used as a tool to assist in undergraduate and postgraduate teaching related to the development of projects concerning on-board control systems.

  12. DEALed : A tool suite for distributed real-time systems development

    NARCIS (Netherlands)

    Bolshakov, K.; Karpov, Y.; Sintotski, A.; Malyshkin, V.

    1999-01-01

    DEALed is a tool suite for development of distributed systems using DEAL language. DEAL is being developed at Eindhoven University of Technology as a part of DEDOS project. Area of application of the DEALed is the development of the distributed real- time safety-critical control systems.

  13. Real-Time Model and Simulation Architecture for Half- and Full-Bridge Modular Multilevel Converters

    Science.gov (United States)

    Ashourloo, Mojtaba

    This work presents an equivalent model and simulation architecture for real-time electromagnetic transient analysis of either half-bridge or full-bridge modular multilevel converter (MMC) with 400 sub-modules (SMs) per arm. The proposed CPU/FPGA-based architecture is optimized for the parallel implementation of the presented MMC model on the FPGA and is beneficiary of a high-throughput floating-point computational engine. The developed real-time simulation architecture is capable of simulating MMCs with 400 SMs per arm at 825 nanoseconds. To address the difficulties of the sorting process implementation, a modified Odd-Even Bubble sorting is presented in this work. The comparison of the results under various test scenarios reveals that the proposed real-time simulator is representing the system responses in the same way of its corresponding off-line counterpart obtained from the PSCAD/EMTDC program.

  14. Real-time simulation of MHD/steam power plants by digital parallel processors

    International Nuclear Information System (INIS)

    Johnson, R.M.; Rudberg, D.A.

    1981-01-01

    Attention is given to a large FORTRAN coded program which simulates the dynamic response of the MHD/steam plant on either a SEL 32/55 or VAX 11/780 computer. The code realizes a detailed first-principle model of the plant. Quite recently, in addition to the VAX 11/780, an AD-10 has been installed for usage as a real-time simulation facility. The parallel processor AD-10 is capable of simulating the MHD/steam plant at several times real-time rates. This is desirable in order to develop rapidly a large data base of varied plant operating conditions. The combined-cycle MHD/steam plant model is discussed, taking into account a number of disadvantages. The disadvantages can be overcome with the aid of an array processor used as an adjunct to the unit processor. The conversion of some computations for real-time simulation is considered

  15. Real-time simulation requirements for study and optimization of power system controls

    Energy Technology Data Exchange (ETDEWEB)

    Nakra, Harbans; McCallum, David; Gagnon, Charles [Institut de Recherche d` Hydro-Quebec, Quebec, PQ (Canada); Venne, Andre; Gagnon, Julien [Hydro-Quebec, Montreal, PQ (Canada)

    1994-12-31

    At the time of ordering for the multi-terminal dc system linking Hydro-Quebec with New England, Hydro-Quebec also ordered functionally duplicate controls of all the converters and installed these in its real time simulation laboratory. The Hydro-Quebec ac system was also simulated in detail and the testing of the controls as thus made possible in a realistic environment. Many field tests were duplicated and many additional tests were done for correction and optimization. This paper describes some of the features of the real-time simulation carried out for this purpose. (author) 3 figs.

  16. Use of high performance networks and supercomputers for real-time flight simulation

    Science.gov (United States)

    Cleveland, Jeff I., II

    1993-01-01

    In order to meet the stringent time-critical requirements for real-time man-in-the-loop flight simulation, computer processing operations must be consistent in processing time and be completed in as short a time as possible. These operations include simulation mathematical model computation and data input/output to the simulators. In 1986, in response to increased demands for flight simulation performance, NASA's Langley Research Center (LaRC), working with the contractor, developed extensions to the Computer Automated Measurement and Control (CAMAC) technology which resulted in a factor of ten increase in the effective bandwidth and reduced latency of modules necessary for simulator communication. This technology extension is being used by more than 80 leading technological developers in the United States, Canada, and Europe. Included among the commercial applications are nuclear process control, power grid analysis, process monitoring, real-time simulation, and radar data acquisition. Personnel at LaRC are completing the development of the use of supercomputers for mathematical model computation to support real-time flight simulation. This includes the development of a real-time operating system and development of specialized software and hardware for the simulator network. This paper describes the data acquisition technology and the development of supercomputing for flight simulation.

  17. Monitoring Distributed Real-Time Systems: A Survey and Future Directions

    Science.gov (United States)

    Goodloe, Alwyn E.; Pike, Lee

    2010-01-01

    Runtime monitors have been proposed as a means to increase the reliability of safety-critical systems. In particular, this report addresses runtime monitors for distributed hard real-time systems. This class of systems has had little attention from the monitoring community. The need for monitors is shown by discussing examples of avionic systems failure. We survey related work in the field of runtime monitoring. Several potential monitoring architectures for distributed real-time systems are presented along with a discussion of how they might be used to monitor properties of interest.

  18. Real-Time Reactive Power Distribution in Microgrids by Dynamic Programing

    DEFF Research Database (Denmark)

    Levron, Yoash; Beck, Yuval; Katzir, Liran

    2017-01-01

    In this paper a new real-time optimization method for reactive power distribution in microgrids is proposed. The method enables location of a globally optimal distribution of reactive power under normal operating conditions. The method exploits the typical compact structure of microgrids to obtain...... combination of reactive powers, by means of dynamic programming. Since every single step involves a one-dimensional problem, the complexity of the solution is only linear with the number of clusters, and as a result, a globally optimal solution may be obtained in real time. The paper includes the results...

  19. Real-time volumetric deformable models for surgery simulation using finite elements and condensation

    DEFF Research Database (Denmark)

    Bro-Nielsen, Morten; Cotin, S.

    1996-01-01

    This paper discusses the application of SD solid volumetric Finite Element models to surgery simulation. In particular it introduces three new ideas for solving the problem of achieving real-time performance for these models. The simulation system we have developed is described and we demonstrate...

  20. WinGraphics: An optimized windowing environment for interactive real-time simulations

    International Nuclear Information System (INIS)

    Verboncoeur, J.P.; Vahedi, V.

    1989-01-01

    We have developed a customized windowing environment, Win Graphics, which provides particle simulation codes with an interactive user interface. The environment supports real-time animation of the simulation, displaying multiple diagnostics as they evolve in time. In addition, keyboard and printer (PostScript and dot matrix) support is provided. This paper describes this environment

  1. Real-Time Congestion Management in Distribution Networks by Flexible Demand Swap

    DEFF Research Database (Denmark)

    Huang, Shaojun; Wu, Qiuwei

    2017-01-01

    In addition to the day-ahead congestion management in distribution networks, the real-time congestion management is very important because many unforeseen events can occur at the real operation time, e.g. loss of generation of distributed energy resources (DERs) or inaccurate forecast of energy...... pumps (HPs) for real time congestion management. The swap method can maintain the power balance of the system and avoid the imbalance cost of activating the flexibility service. An algorithm for forming swaps through optimal power flow (OPF) and mixed integer linear programming (MILP) is proposed...... consumption or production. Flexibility service from demand will be a good option to solve the real-time congestions if the cost of activating the flexibility service is fully addressed. This paper proposes a new method, namely “swap”, to employ the flexibility service from electric vehicles (EVs) and heat...

  2. Data-driven modeling and real-time distributed control for energy efficient manufacturing systems

    International Nuclear Information System (INIS)

    Zou, Jing; Chang, Qing; Arinez, Jorge; Xiao, Guoxian

    2017-01-01

    As manufacturers face the challenges of increasing global competition and energy saving requirements, it is imperative to seek out opportunities to reduce energy waste and overall cost. In this paper, a novel data-driven stochastic manufacturing system modeling method is proposed to identify and predict energy saving opportunities and their impact on production. A real-time distributed feedback production control policy, which integrates the current and predicted system performance, is established to improve the overall profit and energy efficiency. A case study is presented to demonstrate the effectiveness of the proposed control policy. - Highlights: • A data-driven stochastic manufacturing system model is proposed. • Real-time system performance and energy saving opportunity identification method is developed. • Prediction method for future potential system performance and energy saving opportunity is developed. • A real-time distributed feedback control policy is established to improve energy efficiency and overall system profit.

  3. Feasibility study of teleoperational maintenance using real-time simulator for experimental fusion reactor

    International Nuclear Information System (INIS)

    Hamada, Tomoyuki; Tanaka, Keiji; Oka, Kiyoshi; Shibanuma, Kiyoshi

    2004-01-01

    The maintenance manipulator for the experimental fusion reactor has long vertical and horizontal telescopic booms to access the neutral beam injector of the fusion reactor. Due to this boom structure, the vibration and deflection of the manipulator are the critical issues for the accurate operation. A real-time simulation system was constructed to evaluate the maneuverability of the manipulator under these vibration and deflection. In this simulation system, the dynamic behavior of the flexible manipulator is calculated synchronized with the real-time control input of the human operator. A vibration and position compensation method was adapted to improve the maneuverability. Through the evaluation using the real-time simulation system, it was verified that the manipulator is maneuverable by using vibration and position compensation. (author)

  4. Unidata Internet Data Distribution (IDD) and THematic Real-time Environmental Distributed Data Services (THREDDS)

    Science.gov (United States)

    Domenico, B.

    2001-12-01

    Universities across the nation are transforming their teaching and research efforts through increased use of a rapidly expanding menu of environmental data. With funding from the Division of Atmospheric Sciences (ATM ) of the National Science Foundation (NSF), the Unidata Program is playing a central role in this transformation by enabling universities to employ innovative computing and networking technologies to acquire such data sets in real-time and use them routinely in their classrooms and research labs. Working with the Unidata Program Center (UPC), the Unidata community, comprising over 140 departments, has built a national Internet Data Distribution (IDD ) system. The IDD allows users to "subscribe" to certain sets of data products; IDD servers then deliver the requested data to their local servers as soon as they are available from the source. With the initial national implementation in 1994, the IDD may have been the original example of Internet "push" technology. It now provides the reliability, flexibility, and efficiency required by participating institutions. As the underlying Internet technology evolves, we anticipate dramatic increases in the volume of data delivered. We plan to augment the system to better serve disciplines outside the atmospheric sciences and to incorporate anticipated new networking technologies to minimize the impact of the IDD on the underlying network. Unidata has recently undertaken a new initiative called THREDDS (THematic Real-time Environmental Distributed Data Services) under a grant from the NSF Division of Undergraduate Education NSDL (National Science, Math, Engineering, Technology Education Digital Library). The goal of THREDDs is to make it possible for students, educators and researchers to publish, contribute, find, and interact with data relating to the Earth system in a convenient, effective, and integrated fashion. Just as the World Wide Web and digital-library technologies have simplified the process of

  5. Adaptive multi-rate interface: development and experimental verification for real-time hybrid simulation

    DEFF Research Database (Denmark)

    Maghareh, Amin; Waldbjørn, Jacob Paamand; Dyke, Shirley J.

    2016-01-01

    Real-time hybrid simulation (RTHS) is a powerful cyber-physical technique that is a relatively cost-effective method to perform global/local system evaluation of structural systems. A major factor that determines the ability of an RTHS to represent true system-level behavior is the fidelity...... of the numerical substructure. While the use of higher-order models increases fidelity of the simulation, it also increases the demand for computational resources. Because RTHS is executed at real-time, in a conventional RTHS configuration, this increase in computational resources may limit the achievable sampling...

  6. Three axis electronic flight motion simulator real time control system design and implementation

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Zhiyuan; Miao, Zhonghua, E-mail: zhonghua-miao@163.com; Wang, Xiaohua [School of Mechatronic Engineering and Automation, Shanghai University, Shanghai, 200072 (China); Wang, Xuyong [School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China)

    2014-12-15

    A three axis electronic flight motion simulator is reported in this paper including the modelling, the controller design as well as the hardware implementation. This flight motion simulator could be used for inertial navigation test and high precision inertial navigation system with good dynamic and static performances. A real time control system is designed, several control system implementation problems were solved including time unification with parallel port interrupt, high speed finding-zero method of rotary inductosyn, zero-crossing management with continuous rotary, etc. Tests were carried out to show the effectiveness of the proposed real time control system.

  7. Three axis electronic flight motion simulator real time control system design and implementation.

    Science.gov (United States)

    Gao, Zhiyuan; Miao, Zhonghua; Wang, Xuyong; Wang, Xiaohua

    2014-12-01

    A three axis electronic flight motion simulator is reported in this paper including the modelling, the controller design as well as the hardware implementation. This flight motion simulator could be used for inertial navigation test and high precision inertial navigation system with good dynamic and static performances. A real time control system is designed, several control system implementation problems were solved including time unification with parallel port interrupt, high speed finding-zero method of rotary inductosyn, zero-crossing management with continuous rotary, etc. Tests were carried out to show the effectiveness of the proposed real time control system.

  8. Virtual reality myringotomy simulation with real-time deformation: development and validity testing.

    Science.gov (United States)

    Ho, Andrew K; Alsaffar, Hussain; Doyle, Philip C; Ladak, Hanif M; Agrawal, Sumit K

    2012-08-01

    Surgical simulation is becoming an increasingly common training tool in residency programs. The first objective was to implement real-time soft-tissue deformation and cutting into a virtual reality myringotomy simulator. The second objective was to test the various implemented incision algorithms to determine which most accurately represents the tympanic membrane during myringotomy. Descriptive and face-validity testing. A deformable tympanic membrane was developed, and three soft-tissue cutting algorithms were successfully implemented into the virtual reality myringotomy simulator. The algorithms included element removal, direction prediction, and Delaunay cutting. The simulator was stable and capable of running in real time on inexpensive hardware. A face-validity study was then carried out using a validated questionnaire given to eight otolaryngologists and four senior otolaryngology residents. Each participant was given an adaptation period on the simulator, was blinded to the algorithm being used, and was presented the three algorithms in a randomized order. A virtual reality myringotomy simulator with real-time soft-tissue deformation and cutting was successfully developed. The simulator was stable, ran in real time on inexpensive hardware, and incorporated haptic feedback and stereoscopic vision. The Delaunay cutting algorithm was found to be the most realistic algorithm representing the incision during myringotomy (P virtual reality myringotomy simulator is being developed and now integrates a real-time deformable tympanic membrane that appears to have face validity. Further development and validation studies are necessary before the simulator can be studied with respect to training efficacy and clinical impact. Copyright © 2012 The American Laryngological, Rhinological, and Otological Society, Inc.

  9. Real-time simulation of the nonlinear visco-elastic deformations of soft tissues.

    Science.gov (United States)

    Basafa, Ehsan; Farahmand, Farzam

    2011-05-01

    Mass-spring-damper (MSD) models are often used for real-time surgery simulation due to their fast response and fairly realistic deformation replication. An improved real time simulation model of soft tissue deformation due to a laparoscopic surgical indenter was developed and tested. The mechanical realization of conventional MSD models was improved using nonlinear springs and nodal dampers, while their high computational efficiency was maintained using an adapted implicit integration algorithm. New practical algorithms for model parameter tuning, collision detection, and simulation were incorporated. The model was able to replicate complex biological soft tissue mechanical properties under large deformations, i.e., the nonlinear and viscoelastic behaviors. The simulated response of the model after tuning of its parameters to the experimental data of a deer liver sample, closely tracked the reference data with high correlation and maximum relative differences of less than 5 and 10%, for the tuning and testing data sets respectively. Finally, implementation of the proposed model and algorithms in a graphical environment resulted in a real-time simulation with update rates of 150 Hz for interactive deformation and haptic manipulation, and 30 Hz for visual rendering. The proposed real time simulation model of soft tissue deformation due to a laparoscopic surgical indenter was efficient, realistic, and accurate in ex vivo testing. This model is a suitable candidate for testing in vivo during laparoscopic surgery.

  10. Real-time simulation of aeroelastic rotor loads for horizontal axis wind turbines

    International Nuclear Information System (INIS)

    Marnett, M; Wellenberg, S; Schröder, W

    2014-01-01

    Wind turbine drivetrain research and test facilities with hardware-in-the-loop capabilities require a robust and accurate aeroelastic real-time rotor simulation environment. Recent simulation environments do not guarantee a computational response at real-time. Which is why a novel simulation tool has been developed. It resolves the physical time domain of the turbulent wind spectra and the operational response of the turbine at real-time conditions. Therefore, there is a trade-off between accuracy of the physical models and the computational costs. However, the study shows the possibility to preserve the necessary computational accuracy while simultaneously granting dynamic interaction with the aeroelastic rotor simulation environment. The achieved computational costs allow a complete aeroelastic rotor simulation at a resolution frequency of 100 Hz on standard computer platforms. Results obtained for the 5-MW reference wind turbine by the National Renewable Energy Laboratory (NREL) are discussed and compared to NREL's fatigue, aerodynamics, structures, and turbulence (FAST)- Code. The rotor loads show a convincing match. The novel simulation tool is applied to the wind turbine drivetrain test facility at the Center for Wind Power Drives (CWD), RWTH Aachen University to show the real-time hardware-in-the-loop capabilities

  11. A real-time networked camera system : a scheduled distributed camera system reduces the latency

    NARCIS (Netherlands)

    Karatoy, H.

    2012-01-01

    This report presents the results of a Real-time Networked Camera System, com-missioned by the SAN Group in TU/e. Distributed Systems are motivated by two reasons, the first reason is the physical environment as a requirement and the second reason is to provide a better Quality of Service (QoS). This

  12. Robustness of parameter-less remote real-time pressure control in water distribution systems

    CSIR Research Space (South Africa)

    Page, Philip R

    2017-06-01

    Full Text Available One way of reducing water leakage, pipe bursts and water consumption in a water distribution system (WDS) is to manage the pressure to be as low as possible. This can be done by adjusting a pressure control valve (PCV) in real-time in order to keep...

  13. Validation Support for Distributed Real-Time Embedded Systems in VDM++

    DEFF Research Database (Denmark)

    S. Fitzgerald, John; Gorm Larsen, Peter; Tjell, Simon

    2007-01-01

    We present a tool-supported approach to the validation of system-level timing properties in formal models of distributed real-time embedded systems. Our aim is to provide system architects with rapid feedback on the timing characteristics of alternative designs in the often volatile early stages ...

  14. Real-time distributed economic model predictive control for complete vehicle energy management

    NARCIS (Netherlands)

    Romijn, Constantijn; Donkers, Tijs; Kessels, John; Weiland, Siep

    2017-01-01

    In this paper, a real-time distributed economic model predictive control approach for complete vehicle energy management (CVEM) is presented using a receding control horizon in combination with a dual decomposition. The dual decomposition allows the CVEM optimization problem to be solved by solving

  15. Design optimization of TTEthernet-based distributed real-time systems

    DEFF Research Database (Denmark)

    Tamas-Selicean, Domitian; Pop, Paul; Steiner, Wilfried

    2015-01-01

    Many safety-critical real-time applications are implemented using distributed architectures, composed of heterogeneous processing elements interconnected in a network. Our focus in this paper is on the TTEthernet protocol, a deterministic, synchronized and congestion-free network protocol based o...

  16. Flexibility Driven Scheduling and Mapping for Distributed Real-Time Systems

    DEFF Research Database (Denmark)

    Pop, Paul; Eles, Petru; Peng, Zebo

    2002-01-01

    In this paper we present an approach to mapping and scheduling of distributed hard real-time systems, aiming at improving the flexibility of the design process. We consider an incremental design process that starts from an already existing system running a set of applications, with preemptive...

  17. The response time distribution in a real-time database with optimistic concurrency control

    NARCIS (Netherlands)

    Sassen, S.A.E.; Wal, van der J.

    1996-01-01

    For a real-time shared-memory database with optimistic concurrency control, an approximation for the transaction response time distribution is obtained. The model assumes that transactions arrive at the database according to a Poisson process, that every transaction uses an equal number of

  18. Energy-Aware Synthesis of Fault-Tolerant Schedules for Real-Time Distributed Embedded Systems

    DEFF Research Database (Denmark)

    Poulsen, Kåre Harbo; Pop, Paul; Izosimov, Viacheslav

    2007-01-01

    This paper presents a design optimisation tool for distributed embedded real-time systems that 1) decides mapping, fault-tolerance policy and generates a fault-tolerant schedule, 2) is targeted for hard real-time, 3) has hard reliability goal, 4) generates static schedule for processes and messages......, 5) provides fault-tolerance for k transient/soft faults, 6) optimises for minimal energy consumption, while considering impact of lowering voltages on the probability of faults, 7) uses constraint logic programming (CLP) based implementation....

  19. Power in the loop real time simulation platform for renewable energy generation

    Science.gov (United States)

    Li, Yang; Shi, Wenhui; Zhang, Xing; He, Guoqing

    2018-02-01

    Nowadays, a large scale of renewable energy sources has been connecting to power system and the real time simulation platform is widely used to carry out research on integration control algorithm, power system stability etc. Compared to traditional pure digital simulation and hardware in the loop simulation, power in the loop simulation has higher accuracy and degree of reliability. In this paper, a power in the loop analog digital hybrid simulation platform has been built and it can be used not only for the single generation unit connecting to grid, but also for multiple new energy generation units connecting to grid. A wind generator inertia control experiment was carried out on the platform. The structure of the inertia control platform was researched and the results verify that the platform is up to need for renewable power in the loop real time simulation.

  20. Implementation of the frequency dependent line model in a real-time power system simulator

    Directory of Open Access Journals (Sweden)

    Reynaldo Iracheta-Cortez

    2017-09-01

    Full Text Available In this paper is described the implementation of the frequency-dependent line model (FD-Line in a real-time digital power system simulator. The main goal with such development is to describe a general procedure to incorporate new realistic models of power system components in modern real-time simulators based on the Electromagnetic Transients Program (EMTP. In this procedure are described, firstly, the steps to obtain the time domain solution of the differential equations that models the electromagnetic behavior in multi-phase transmission lines with frequency dependent parameters. After, the algorithmic solution of the FD-Line model is implemented in Simulink environment, through an S-function programmed in C language, for running off-line simulations of electromagnetic transients. This implementation allows the free assembling of the FD Line model with any element of the Power System Blockset library and also, it can be used to build any network topology. The main advantage of having a power network built in Simulink is that can be executed in real-time by means of the commercial eMEGAsim simulator. Finally, several simulation cases are presented to validate the accuracy and the real-time performance of the FD-Line model.

  1. On the choice of the demand and hydraulic modeling approach to WDN real-time simulation

    Science.gov (United States)

    Creaco, Enrico; Pezzinga, Giuseppe; Savic, Dragan

    2017-07-01

    This paper aims to analyze two demand modeling approaches, i.e., top-down deterministic (TDA) and bottom-up stochastic (BUA), with particular reference to their impact on the hydraulic modeling of water distribution networks (WDNs). In the applications, the hydraulic modeling is carried out through the extended period simulation (EPS) and unsteady flow modeling (UFM). Taking as benchmark the modeling conditions that are closest to the WDN's real operation (UFM + BUA), the analysis showed that the traditional use of EPS + TDA produces large pressure head and water discharge errors, which can be attenuated only when large temporal steps (up to 1 h in the case study) are used inside EPS. The use of EPS + BUA always yields better results. Indeed, EPS + BUA already gives a good approximation of the WDN's real operation when intermediate temporal steps (larger than 2 min in the case study) are used for the simulation. The trade-off between consistency of results and computational burden makes EPS + BUA the most suitable tool for real-time WDN simulation, while benefitting from data acquired through smart meters for the parameterization of demand generation models.

  2. Real-Time Simulation Technique of a Microgrid Model for DER Penetration

    Directory of Open Access Journals (Sweden)

    Konstantina Mentesidi

    2014-12-01

    Full Text Available Comprehensive analysis of Distributed Energy Resources (DER integration requires tools that provide computational power and flexibility. In this context, throughout this paper PHIL simulations are performed to emulate the energy management system of a real microgrid including a diesel synchronous machine and inverter-based sources. Moreover, conventional frequency and voltage droops were incorporated into the respective inverters. The results were verified at the real microgrid installation in the Centre for Renewable Energy Sources (CRES premises. This research work is divided into two steps: A Real time in RSCAD/RTDS and Power Hardware-in-the-Loop (PHIL simulations where the diesel generator´s active power droop control is evaluated, the battery inverter´s droop curves are simulated and the load sharing for parallel operation of the system´s generation units is examined. B microgrid experiments during which various tests were executed concerning the diesel generator and the battery inverters in order to examine their dynamic operation within the LV islanded power system.

  3. Coarse-grained simulation of a real-time process control network under peak load

    International Nuclear Information System (INIS)

    George, A.D.; Clapp, N.E. Jr.

    1992-01-01

    This paper presents a simulation study on the real-time process control network proposed for the new ANS reactor system at ORNL. A background discussion is provided on networks, modeling, and simulation, followed by an overview of the ANS process control network, its three peak-load models, and the results of a series of coarse-grained simulation studies carried out on these models using implementations of 802.3, 802.4, and 802.5 standard local area networks

  4. Real-time dynamic simulator for the Topaz II reactor power system

    International Nuclear Information System (INIS)

    Kwok, K.S.

    1994-01-01

    A dynamic simulator of the TOPAZ II reactor system has been developed for the Nuclear Electric Propulsion Space Test Program. The simulator is a self-contained IBM-PC compatible based system that executes at a speed faster than real-time. The simulator combines first-principle modeling and empirical correlations in its algorithm to attain the modeling accuracy and computational through-put that are required for real-time execution. The overall execution time of the simulator for each time step is 15 ms when no data is written to the disk, and 18 ms when nine double precision data points are written to the disk once in every time step. The simulation program has been tested and it is able to handle a step decrease of $8 worth of reactivity. It also provides simulation of fuel, emitter, collector, stainless steel, and ZrH moderator failures. Presented in this paper are the models used in the calculations, a sample simulation session, and a discussion of the performance and limitations of the simulator. The simulator has been found to provide realistic real-time dynamic response of the TOPAZ II reactor system under both normal and causality conditions

  5. project SENSE : multimodal simulation with full-body real-time verbal and nonverbal interactions

    NARCIS (Netherlands)

    Miri, Hossein; Kolkmeier, Jan; Taylor, Paul Jonathon; Poppe, Ronald; Heylen, Dirk; Poppe, Ronald; Meyer, John-Jules; Veltkamp, Remco; Dastani, Mehdi

    2016-01-01

    This paper presents a multimodal simulation system, project-SENSE, that combines virtual reality and full-body motion capture technologies with real-time verbal and nonverbal communication. We introduce the technical setup and employed hardware and software of a first prototype. We discuss the

  6. Real-time simulation of the Space Station mobile service center

    Science.gov (United States)

    Thomas, Segun

    1988-01-01

    A method for building a generic N-joint simulation program is presented. It is shown that the multibody program can be operated in real time using a careful connection-array numbering scheme and a preprocessor. An example of a rigid manipulator on the Shuttle Orbiter was used to demonstrate the implementation technique.

  7. A multi-GPU real-time dose simulation software framework for lung radiotherapy.

    Science.gov (United States)

    Santhanam, A P; Min, Y; Neelakkantan, H; Papp, N; Meeks, S L; Kupelian, P A

    2012-09-01

    Medical simulation frameworks facilitate both the preoperative and postoperative analysis of the patient's pathophysical condition. Of particular importance is the simulation of radiation dose delivery for real-time radiotherapy monitoring and retrospective analyses of the patient's treatment. In this paper, a software framework tailored for the development of simulation-based real-time radiation dose monitoring medical applications is discussed. A multi-GPU-based computational framework coupled with inter-process communication methods is introduced for simulating the radiation dose delivery on a deformable 3D volumetric lung model and its real-time visualization. The model deformation and the corresponding dose calculation are allocated among the GPUs in a task-specific manner and is performed in a pipelined manner. Radiation dose calculations are computed on two different GPU hardware architectures. The integration of this computational framework with a front-end software layer and back-end patient database repository is also discussed. Real-time simulation of the dose delivered is achieved at once every 120 ms using the proposed framework. With a linear increase in the number of GPU cores, the computational time of the simulation was linearly decreased. The inter-process communication time also improved with an increase in the hardware memory. Variations in the delivered dose and computational speedup for variations in the data dimensions are investigated using D70 and D90 as well as gEUD as metrics for a set of 14 patients. Computational speed-up increased with an increase in the beam dimensions when compared with a CPU-based commercial software while the error in the dose calculation was lung model-based radiotherapy is an effective tool for performing both real-time and retrospective analyses.

  8. Real-Time and Real-Fast Performance of General-Purpose and Real-Time Operating Systems in Multithreaded Physical Simulation of Complex Mechanical Systems

    Directory of Open Access Journals (Sweden)

    Carlos Garre

    2014-01-01

    Full Text Available Physical simulation is a valuable tool in many fields of engineering for the tasks of design, prototyping, and testing. General-purpose operating systems (GPOS are designed for real-fast tasks, such as offline simulation of complex physical models that should finish as soon as possible. Interfacing hardware at a given rate (as in a hardware-in-the-loop test requires instead maximizing time determinism, for which real-time operating systems (RTOS are designed. In this paper, real-fast and real-time performance of RTOS and GPOS are compared when simulating models of high complexity with large time steps. This type of applications is usually present in the automotive industry and requires a good trade-off between real-fast and real-time performance. The performance of an RTOS and a GPOS is compared by running a tire model scalable on the number of degrees-of-freedom and parallel threads. The benchmark shows that the GPOS present better performance in real-fast runs but worse in real-time due to nonexplicit task switches and to the latency associated with interprocess communication (IPC and task switch.

  9. A new ChainMail approach for real-time soft tissue simulation.

    Science.gov (United States)

    Zhang, Jinao; Zhong, Yongmin; Smith, Julian; Gu, Chengfan

    2016-07-03

    This paper presents a new ChainMail method for real-time soft tissue simulation. This method enables the use of different material properties for chain elements to accommodate various materials. Based on the ChainMail bounding region, a new time-saving scheme is developed to improve computational efficiency for isotropic materials. The proposed method also conserves volume and strain energy. Experimental results demonstrate that the proposed ChainMail method can not only accommodate isotropic, anisotropic and heterogeneous materials but also model incompressibility and relaxation behaviors of soft tissues. Further, the proposed method can achieve real-time computational performance.

  10. Real-Time Countermeasures Preventing Power System Instability by using PMU data from RTDS simulation

    DEFF Research Database (Denmark)

    Karatas, Bahtiyar Can; Jóhannsson, Hjörtur; Nielsen, Arne Hejde

    2016-01-01

    This paper presents an innovative approach to apply wide-area control actions in real-time and prevent emerging instability. A software platform has been further developed, which utilizes Real Time Digital Simulator (RTDS) technology to prevent scenarios leading to power system instability....... The software platform receives phasor measurement unit (PMU) data at a high repetition rate for full system observability. The PMU data serves as input for methods capable of analyzing the steady state torque balance for each individual generator and to determine available power reserves and possible remedial...

  11. Internet Data Distribution – extending real-time data sharing throughout the Americas

    Directory of Open Access Journals (Sweden)

    T. Yoksas

    2006-01-01

    Full Text Available The Unidata Program Center (Unidata of the University Corporation of Atmospheric Research (UCAR is involved in three international collaborations whose goals are extension of real-time data delivery-to and sharing-of locally held datasets-by educational institutions throughout the Americas. These efforts are based on the use of Unidata's Internet Data Distribution (IDD system which is built on top of its proven Local Data Manager Version 6 (LDM-6 technology. The Unidata IDD is an event-driven network of cooperating Unidata LDM servers that distributes discipline-neutral data products in near real-time over wide-area networks. The IDD, a collaboration of over 150 mostly North American institutions of higher education, has been the primary source of real-time atmospheric science data for the US university community for over a decade,. In addition to providing a highly reliable mechanism for delivering real-time data, the IDD allows users to easily share locally held datasets.

  12. Operating system for a real-time multiprocessor propulsion system simulator

    Science.gov (United States)

    Cole, G. L.

    1984-01-01

    The success of the Real Time Multiprocessor Operating System (RTMPOS) in the development and evaluation of experimental hardware and software systems for real time interactive simulation of air breathing propulsion systems was evaluated. The Real Time Multiprocessor Operating System (RTMPOS) provides the user with a versatile, interactive means for loading, running, debugging and obtaining results from a multiprocessor based simulator. A front end processor (FEP) serves as the simulator controller and interface between the user and the simulator. These functions are facilitated by the RTMPOS which resides on the FEP. The RTMPOS acts in conjunction with the FEP's manufacturer supplied disk operating system that provides typical utilities like an assembler, linkage editor, text editor, file handling services, etc. Once a simulation is formulated, the RTMPOS provides for engineering level, run time operations such as loading, modifying and specifying computation flow of programs, simulator mode control, data handling and run time monitoring. Run time monitoring is a powerful feature of RTMPOS that allows the user to record all actions taken during a simulation session and to receive advisories from the simulator via the FEP. The RTMPOS is programmed mainly in PASCAL along with some assembly language routines. The RTMPOS software is easily modified to be applicable to hardware from different manufacturers.

  13. Design base transient analysis using the real-time nuclear reactor simulator model

    International Nuclear Information System (INIS)

    Tien, K.K.; Yakura, S.J.; Morin, J.P.; Gregory, M.V.

    1987-01-01

    A real-time simulation model has been developed to describe the dynamic response of all major systems in a nuclear process reactor. The model consists of a detailed representation of all hydraulic components in the external coolant circulating loops consisting of piping, valves, pumps and heat exchangers. The reactor core is described by a three-dimensional neutron kinetics model with detailed representation of assembly coolant and moderator thermal hydraulics. The models have been developed to support a real-time training simulator, therefore, they reproduce system parameters characteristic of steady state normal operation with high precision. The system responses for postulated severe transients such as large pipe breaks, loss of pumping power, piping leaks, malfunctions in control rod insertion, and emergency injection of neutron absorber are calculated to be in good agreement with reference safety analyses. Restrictions were imposed by the requirement that the resulting code be able to run in real-time with sufficient spare time to allow interfacing with secondary systems and simulator hardware. Due to hardware set-up and real plant instrumentation, simplifications due to symmetry were not allowed. The resulting code represents a coarse-node engineering model in which the level of detail has been tailored to the available computing power of a present generation super-minicomputer. Results for several significant transients, as calculated by the real-time model, are compared both to actual plant data and to results generated by fine-mesh analysis codes

  14. Design base transient analysis using the real-time nuclear reactor simulator model

    International Nuclear Information System (INIS)

    Tien, K.K.; Yakura, S.J.; Morin, J.P.; Gregory, M.V.

    1987-01-01

    A real-time simulation model has been developed to describe the dynamic response of all major systems in a nuclear process reactor. The model consists of a detailed representation of all hydraulic components in the external coolant circulating loops consisting of piping, valves, pumps and heat exchangers. The reactor core is described by a three-dimensional neutron kinetics model with detailed representation of assembly coolant and mode-rator thermal hydraulics. The models have been developed to support a real-time training simulator, therefore, they reproduce system parameters characteristic of steady state normal operation with high precision. The system responses for postulated severe transients such as large pipe breaks, loss of pumping power, piping leaks, malfunctions in control rod insertion, and emergency injection of neutron absorber are calculated to be in good agreement with reference safety analyses. Restrictions were imposed by the requirement that the resulting code be able to run in real-time with sufficient spare time to allow interfacing with secondary systems and simulator hardware. Due to hardware set-up and real plant instrumentation, simplifications due to symmetry were not allowed. The resulting code represents a coarse-node engineering model in which the level of detail has been tailored to the available computing power of a present generation super-minicomputer. Results for several significant transients, as calculated by the real-time model, are compared both to actual plant data and to results generated by fine-mesh analysis codes

  15. Architecture for an integrated real-time air combat and sensor network simulation

    Science.gov (United States)

    Criswell, Evans A.; Rushing, John; Lin, Hong; Graves, Sara

    2007-04-01

    An architecture for an integrated air combat and sensor network simulation is presented. The architecture integrates two components: a parallel real-time sensor fusion and target tracking simulation, and an air combat simulation. By integrating these two simulations, it becomes possible to experiment with scenarios in which one or both sides in a battle have very large numbers of primitive passive sensors, and to assess the likely effects of those sensors on the outcome of the battle. Modern Air Power is a real-time theater-level air combat simulation that is currently being used as a part of the USAF Air and Space Basic Course (ASBC). The simulation includes a variety of scenarios from the Vietnam war to the present day, and also includes several hypothetical future scenarios. Modern Air Power includes a scenario editor, an order of battle editor, and full AI customization features that make it possible to quickly construct scenarios for any conflict of interest. The scenario editor makes it possible to place a wide variety of sensors including both high fidelity sensors such as radars, and primitive passive sensors that provide only very limited information. The parallel real-time sensor network simulation is capable of handling very large numbers of sensors on a computing cluster of modest size. It can fuse information provided by disparate sensors to detect and track targets, and produce target tracks.

  16. From distributed to multicore architecture in the RFX-mod real time control system

    International Nuclear Information System (INIS)

    Manduchi, G.; Luchetta, A.; Soppelsa, A.; Taliercio, C.

    2014-01-01

    Highlights: • The paper describes the experience in running the real-time control system of RFX-mod. • It presents a new architecture based on multicore technology. • It analyze the feasibility of Linux MRG for real-time control. • It presents an application of the MARTe framework. - Abstract: The real-time control system of RFX has been operating since 2004 providing effective control of the plasma position and of the MagnetoHydroDynamic (MHD) modes. The demand for new and more computing-intensive control algorithms and the need for shorter latency pushed the system to its limits and, thus, a complete re-design was carried out in 2012. The new system adopts radically different solutions in hardware, operating system and software management. The VME PowerPC CPUs communicating over Ethernet have been now replaced by a single multicore server. VxWorks, previously used in the VME CPUs has now been replaced by Linux, which can be currently considered a real-time system provided an accurate tuning of the Linux scheduler and interrupt configuration. The previous framework for control and communication has been replaced by MARTe, a modern framework for real-time control gaining interest in the fusion community. The usage of MARTe allowed a rapid development of the control system and, in particular, its intrinsic simulation ability gave us the possibility of carrying out most debugging in simulation, without affecting machine operation. As a result the whole system has been finally commissioned in RFX in only two weeks

  17. From distributed to multicore architecture in the RFX-mod real time control system

    Energy Technology Data Exchange (ETDEWEB)

    Manduchi, G., E-mail: gabriele.manduchi@igi.cnr.it; Luchetta, A.; Soppelsa, A.; Taliercio, C.

    2014-03-15

    Highlights: • The paper describes the experience in running the real-time control system of RFX-mod. • It presents a new architecture based on multicore technology. • It analyze the feasibility of Linux MRG for real-time control. • It presents an application of the MARTe framework. - Abstract: The real-time control system of RFX has been operating since 2004 providing effective control of the plasma position and of the MagnetoHydroDynamic (MHD) modes. The demand for new and more computing-intensive control algorithms and the need for shorter latency pushed the system to its limits and, thus, a complete re-design was carried out in 2012. The new system adopts radically different solutions in hardware, operating system and software management. The VME PowerPC CPUs communicating over Ethernet have been now replaced by a single multicore server. VxWorks, previously used in the VME CPUs has now been replaced by Linux, which can be currently considered a real-time system provided an accurate tuning of the Linux scheduler and interrupt configuration. The previous framework for control and communication has been replaced by MARTe, a modern framework for real-time control gaining interest in the fusion community. The usage of MARTe allowed a rapid development of the control system and, in particular, its intrinsic simulation ability gave us the possibility of carrying out most debugging in simulation, without affecting machine operation. As a result the whole system has been finally commissioned in RFX in only two weeks.

  18. Parallel Motion Simulation of Large-Scale Real-Time Crowd in a Hierarchical Environmental Model

    Directory of Open Access Journals (Sweden)

    Xin Wang

    2012-01-01

    Full Text Available This paper presents a parallel real-time crowd simulation method based on a hierarchical environmental model. A dynamical model of the complex environment should be constructed to simulate the state transition and propagation of individual motions. By modeling of a virtual environment where virtual crowds reside, we employ different parallel methods on a topological layer, a path layer and a perceptual layer. We propose a parallel motion path matching method based on the path layer and a parallel crowd simulation method based on the perceptual layer. The large-scale real-time crowd simulation becomes possible with these methods. Numerical experiments are carried out to demonstrate the methods and results.

  19. Real Time Photovoltaic Array Simulator for Testing Grid-Connected PV Inverters

    DEFF Research Database (Denmark)

    Sera, Dezso; Valentini, Massimo; Raducu, Alin

    2008-01-01

    In this paper a real time flexible PV array simulator is presented. It is a system that can simulate different PV panel arrays in specific environmental conditions. To evaluate performance of the Maximum Power Point Tracking (MPPT) of grid-connected Photovoltaic (PV) inverters only measurements...... undertaken with an appropriate PV array simulator provide accurate and reproducible results. Thus the PV array simulator has been developed and implemented. MPPT efficiency tests on a commercial grid-connected PV inverter have been performed to validate the PV array simulator....

  20. Hard real-time multibody simulations using ARM-based embedded systems

    Energy Technology Data Exchange (ETDEWEB)

    Pastorino, Roland, E-mail: roland.pastorino@kuleuven.be, E-mail: rpastorino@udc.es; Cosco, Francesco, E-mail: francesco.cosco@kuleuven.be; Naets, Frank, E-mail: frank.naets@kuleuven.be; Desmet, Wim, E-mail: wim.desmet@kuleuven.be [KU Leuven, PMA division, Department of Mechanical Engineering (Belgium); Cuadrado, Javier, E-mail: javicuad@cdf.udc.es [Universidad de La Coruña, Laboratorio de Ingeniería Mecánica (Spain)

    2016-05-15

    The real-time simulation of multibody models on embedded systems is of particular interest for controllers and observers such as model predictive controllers and state observers, which rely on a dynamic model of the process and are customarily executed in electronic control units. This work first identifies the software techniques and tools required to easily write efficient code for multibody models to be simulated on ARM-based embedded systems. Automatic Programming and Source Code Translation are the two techniques that were chosen to generate source code for multibody models in different programming languages. Automatic Programming is used to generate procedural code in an intermediate representation from an object-oriented library and Source Code Translation is used to translate the intermediate representation automatically to an interpreted language or to a compiled language for efficiency purposes. An implementation of these techniques is proposed. It is based on a Python template engine and AST tree walkers for Source Code Generation and on a model-driven translator for the Source Code Translation. The code is translated from a metalanguage to any of the following four programming languages: Python-Numpy, Matlab, C++-Armadillo, C++-Eigen. Two examples of multibody models were simulated: a four-bar linkage with multiple loops and a 3D vehicle steering system. The code for these examples has been generated and executed on two ARM-based single-board computers. Using compiled languages, both models could be simulated faster than real-time despite the low resources and performance of these embedded systems. Finally, the real-time performance of both models was evaluated when executed in hard real-time on Xenomai for both embedded systems. This work shows through measurements that Automatic Programming and Source Code Translation are valuable techniques to develop real-time multibody models to be used in embedded observers and controllers.

  1. Hard real-time multibody simulations using ARM-based embedded systems

    International Nuclear Information System (INIS)

    Pastorino, Roland; Cosco, Francesco; Naets, Frank; Desmet, Wim; Cuadrado, Javier

    2016-01-01

    The real-time simulation of multibody models on embedded systems is of particular interest for controllers and observers such as model predictive controllers and state observers, which rely on a dynamic model of the process and are customarily executed in electronic control units. This work first identifies the software techniques and tools required to easily write efficient code for multibody models to be simulated on ARM-based embedded systems. Automatic Programming and Source Code Translation are the two techniques that were chosen to generate source code for multibody models in different programming languages. Automatic Programming is used to generate procedural code in an intermediate representation from an object-oriented library and Source Code Translation is used to translate the intermediate representation automatically to an interpreted language or to a compiled language for efficiency purposes. An implementation of these techniques is proposed. It is based on a Python template engine and AST tree walkers for Source Code Generation and on a model-driven translator for the Source Code Translation. The code is translated from a metalanguage to any of the following four programming languages: Python-Numpy, Matlab, C++-Armadillo, C++-Eigen. Two examples of multibody models were simulated: a four-bar linkage with multiple loops and a 3D vehicle steering system. The code for these examples has been generated and executed on two ARM-based single-board computers. Using compiled languages, both models could be simulated faster than real-time despite the low resources and performance of these embedded systems. Finally, the real-time performance of both models was evaluated when executed in hard real-time on Xenomai for both embedded systems. This work shows through measurements that Automatic Programming and Source Code Translation are valuable techniques to develop real-time multibody models to be used in embedded observers and controllers.

  2. Collecting real-time data with a behavioral simulation: A new methodological trait

    DEFF Research Database (Denmark)

    Jespersen, Kristina Risom

    interactive methods of collecting data [1, 2]. To collect real-time data as opposed to retrospective data, new methodological traits are needed. The paper proposes that a behavioral simulation supported by Web technology is a valid new research strategy to handle the collection of real-time data. Adapting...... the knowledge on agent-based modeling [3, 4], a behavioral simulation synergizes the benefits of self-administered questionnaires and the experimental design, and furthermore, introduces role-playing [5, 6] and scenario [7-11] strategies as very effective methods to ensure high interaction with the respondents....... The Web technology is the key to make a simulation for data collection objectives 'light'. Additionally, Web technology can be a solution to some of the challenges facing the traditional research methodologies such as time, ease, flexibility and cost, but perhaps more interesting, a possible solution...

  3. Real-time modelling of a ventilation system for a power plant simulator

    International Nuclear Information System (INIS)

    Kocher, P.; Welfonder, E.

    1992-01-01

    This paper describes how to simulate in real-time the ventilation system of a nuclear power plant. The simulation is made under difficult computing time conditions. The ventilation system program is part of a simulator which simulates the whole nuclear power plant process in realtime. Therefore the ventilation system is split up into several smaller units. For each of these process units a real-time module has been developed, being as simple as possible but nevertheless coming close enough to the real dynamic behaviour. After that the simple real-time modules are linked together to form the total dynamic model ''ventilation system''. The continuous dynamic model developed is numerically integrated by the Euler method. The stability of this explicit method is maintained by special modelling measures such as the increasing of too low flow resistances or the limitation of too high gain factors. At the end of the paper some curves, recorded at the simulator, illustrate the behaviour of the ventilation system in the case of an accident. (author)

  4. Control-Oriented Models for Real-Time Simulation of Automotive Transmission Systems

    Directory of Open Access Journals (Sweden)

    Cavina N.

    2015-01-01

    Full Text Available A control-oriented model of a Dual Clutch Transmission (DCT was developed for real-time Hardware In the Loop (HIL applications, to support model-based development of the DCT controller and to systematically test its performance. The model is an innovative attempt to reproduce the fast dynamics of the actuation system while maintaining a simulation step size large enough for real-time applications. The model comprehends a detailed physical description of hydraulic circuit, clutches, synchronizers and gears, and simplified vehicle and internal combustion engine sub-models. As the oil circulating in the system has a large bulk modulus, the pressure dynamics are very fast, possibly causing instability in a real-time simulation; the same challenge involves the servo valves dynamics, due to the very small masses of the moving elements. Therefore, the hydraulic circuit model has been modified and simplified without losing physical validity, in order to adapt it to the real-time simulation requirements. The results of offline simulations have been compared to on-board measurements to verify the validity of the developed model, which was then implemented in a HIL system and connected to the Transmission Control Unit (TCU. Several tests have been performed on the HIL simulator, to verify the TCU performance: electrical failure tests on sensors and actuators, hydraulic and mechanical failure tests on hydraulic valves, clutches and synchronizers, and application tests comprehending all the main features of the control actions performed by the TCU. Being based on physical laws, in every condition the model simulates a plausible reaction of the system. A test automation procedure has finally been developed to permit the execution of a pattern of tests without the interaction of the user; perfectly repeatable tests can be performed for non-regression verification, allowing the testing of new software releases in fully automatic mode.

  5. Real-Time Human in the Loop MBS Simulation in the Fraunhofer Robot-Based Driving Simulator

    Directory of Open Access Journals (Sweden)

    Kleer Michael

    2014-08-01

    Full Text Available The paper encompasses the overview of hardware architecture and the systems characteristics of the Fraunhofer driving simulator. First, the requirements of the real-time model and the real-time calculation hardware are defined and discussed in detail. Aspects like transport delay and the parallel computation of complex real-time models are presented. In addition, the interfacing of the models with the simulator system is shown. Two simulator driving tests, including a fully interactive rough terrain driving with a wheeled excavator and a test drive with a passenger car, are set to demonstrate system characteristics. Furthermore, the simulator characteristics of practical significance, such as simulator response time delay, simulator acceleration signal bandwidth obtained from artificial excitation and from the simulator driving test, will be presented and discussed.

  6. Towards Online Visualization and Interactive Monitoring of Real-Time CFD Simulations on Commodity Hardware

    Directory of Open Access Journals (Sweden)

    Nils Koliha

    2015-09-01

    Full Text Available Real-time rendering in the realm of computational fluid dynamics (CFD in particular and scientific high performance computing (HPC in general is a comparably young field of research, as the complexity of most problems with practical relevance is too high for a real-time numerical simulation. However, recent advances in HPC and the development of very efficient numerical techniques allow running first optimized numerical simulations in or near real-time, which in return requires integrated and optimized visualization techniques that do not affect performance. In this contribution, we present concepts, implementation details and several application examples of a minimally-invasive, efficient visualization tool for the interactive monitoring of 2D and 3D turbulent flow simulations on commodity hardware. The numerical simulations are conducted with ELBE, an efficient lattice Boltzmann environment based on NVIDIA CUDA (Compute Unified Device Architecture, which provides optimized numerical kernels for 2D and 3D computational fluid dynamics with fluid-structure interactions and turbulence.

  7. Dynamic Beam Solutions for Real-Time Simulation and Control Development of Flexible Rockets

    Science.gov (United States)

    Su, Weihua; King, Cecilia K.; Clark, Scott R.; Griffin, Edwin D.; Suhey, Jeffrey D.; Wolf, Michael G.

    2016-01-01

    In this study, flexible rockets are structurally represented by linear beams. Both direct and indirect solutions of beam dynamic equations are sought to facilitate real-time simulation and control development for flexible rockets. The direct solution is completed by numerically integrate the beam structural dynamic equation using an explicit Newmark-based scheme, which allows for stable and fast transient solutions to the dynamics of flexile rockets. Furthermore, in the real-time operation, the bending strain of the beam is measured by fiber optical sensors (FOS) at intermittent locations along the span, while both angular velocity and translational acceleration are measured at a single point by the inertial measurement unit (IMU). Another study in this paper is to find the analytical and numerical solutions of the beam dynamics based on the limited measurement data to facilitate the real-time control development. Numerical studies demonstrate the accuracy of these real-time solutions to the beam dynamics. Such analytical and numerical solutions, when integrated with data processing and control algorithms and mechanisms, have the potential to increase launch availability by processing flight data into the flexible launch vehicle's control system.

  8. Review of Real-time Electricity Markets for Integrating Distributed Energy Resources and Demand Response

    DEFF Research Database (Denmark)

    Wang, Qi; Zhang, Chunyu; Ding, Yi

    2015-01-01

    The high penetration of both Distributed Energy Resources (DER) and Demand Response (DR) in modern power systems requires a sequence of advanced strategies and technologies for maintaining system reliability and flexibility. Real-time electricity markets (RTM) are the nondiscriminatory transaction...... platforms for providing necessary balancing services, where the market clearing (nodal or zonal prices depending on markets) is very close to real time operations of power systems. One of the primary functions of RTMs in modern power systems is establishing an efficient and effective mechanism for small DER...... and DR to participate in balancing market transactions, while handling their meteorological or intermittent characteristics, facilitating asset utilization, and stimulating their active responses. Consequently, RTMs are dedicated to maintaining the flexibility and reliability of power systems. This paper...

  9. A Real-Time, Distributed and Context-Aware System for Managing Solidarity Campaigns

    Directory of Open Access Journals (Sweden)

    Ana OLIVEIRA ALVES

    2016-05-01

    Full Text Available We present a project implemented on the field which has two separate strands, one refers on collecting crowd sensing data through mobile apps where context is (near automatically induced, another is related to a practical application of this method in a real time system to manage solidarity campaigns in collecting goods. Here, we cover both parts, we applied an experimental setup and obtained results and insights in a third sector institution, Caritas Diocesana of Coimbra[1], a non-profit organization part of Caritas[2]. As main contribution, we propose a distributed architecture for Mobile Crowd Sensing able not only to allow real time inventory through simultaneous campaigns but also it gives feedback to volunteers in order to instantly acquire information about which categories of goods are more needed[1] http://www.caritas.pt/site/nacional/ Portuguese Website (last visited in October 2015[2] http://www.caritas.eu/ (last visited in October 2015

  10. The R-Shell approach - Using scheduling agents in complex distributed real-time systems

    Science.gov (United States)

    Natarajan, Swaminathan; Zhao, Wei; Goforth, Andre

    1993-01-01

    Large, complex real-time systems such as space and avionics systems are extremely demanding in their scheduling requirements. The current OS design approaches are quite limited in the capabilities they provide for task scheduling. Typically, they simply implement a particular uniprocessor scheduling strategy and do not provide any special support for network scheduling, overload handling, fault tolerance, distributed processing, etc. Our design of the R-Shell real-time environment fcilitates the implementation of a variety of sophisticated but efficient scheduling strategies, including incorporation of all these capabilities. This is accomplished by the use of scheduling agents which reside in the application run-time environment and are responsible for coordinating the scheduling of the application.

  11. Real-Time Simulation of Coaxial Rotor Configurations with Combined Finite State Dynamic Wake and VPM

    OpenAIRE

    Zhao, Jinggen; He, Chengjian

    2017-01-01

    This paper describes a first-principle based finite state dynamic rotor wake model that addresses the complex aerodynamic interference inherent to coaxial rotor configurations in support of advanced vertical lift aircraft simulation, design, and analysis. The high fidelity rotor dynamic wake solution combines an enhanced real-time finite state dynamic wake model (DYW) with a first-principle based viscous Vortex Particle Method (VPM). The finite state dynamic wake model provides a state-spa...

  12. Simulation of a nuclear measurement system around a multi-task mode real-time monitor

    International Nuclear Information System (INIS)

    De Grandi, G.; Ouiguini, R.

    1983-01-01

    When debugging and testing material and software for the automation of systems, the non-availability of this last one states important logistic problems. A simulator of the system to be automatized, conceived around a multi-task mode real-time monitor, allowing the debugging of the software of automation without the physical presence of the system to be automatized, is proposed in the present report

  13. Real-time simulation of an F110/STOVL turbofan engine

    Science.gov (United States)

    Drummond, Colin K.; Ouzts, Peter J.

    1989-01-01

    A traditional F110-type turbofan engine model was extended to include a ventral nozzle and two thrust-augmenting ejectors for Short Take-Off Vertical Landing (STOVL) aircraft applications. Development of the real-time F110/STOVL simulation required special attention to the modeling approach to component performance maps, the low pressure turbine exit mixing region, and the tailpipe dynamic approximation. Simulation validation derives by comparing output from the ADSIM simulation with the output for a validated F110/STOVL General Electric Aircraft Engines FORTRAN deck. General Electric substantiated basic engine component characteristics through factory testing and full scale ejector data.

  14. Real-time modelling and simulation of an active power filter

    Energy Technology Data Exchange (ETDEWEB)

    Beaulieu, S.; Ouhrouche, M. [Quebec Univ., Chicoutimi, PQ (Canada); Dufour, C.; Allaire, P.F. [Opal RT Technologies Inc., Montreal, PQ (Canada)

    2007-07-01

    Power electronics converters generate harmonics and cause electromagnetic compatibility problems. Active power filter (APF) technology has advanced to the point that it can compensate for harmonics in electrical networks and provide reactive power and neutral current in AC networks. This paper presented a contribution in the design of a shunt APF for harmonics compensation in real-time simulation using the RT-LAB software package running on a simple personal computer. Real-time simulations were performed to validate the effectiveness of the proposed model. Several high-tech industries have adopted this tool for rapid control prototyping and for Hardware-in-the-Loop applications. The switching signals of the APF are determined by the hysteresis band current controller. The suitable current reference signals were determined by the algorithm based on synchronous reference frame. Real-time simulation runs showed good performance in harmonics compensation, thus satisfying the requirements of IEEE Standard 519-1992. The rate of total harmonic distortion for the source current decreased from 30 to 5 per cent. 12 refs., 1 tab., 9 figs.

  15. IGBT Switching Characteristic Curve Embedded Half-Bridge MMC Modelling and Real Time Simulation Realization

    Science.gov (United States)

    Zhengang, Lu; Hongyang, Yu; Xi, Yang

    2017-05-01

    The Modular Multilevel Converter (MMC) is one of the most attractive topologies in recent years for medium or high voltage industrial applications, such as high voltage dc transmission (HVDC) and medium voltage varying speed motor drive. The wide adoption of MMCs in industry is mainly due to its flexible expandability, transformer-less configuration, common dc bus, high reliability from redundancy, and so on. But, when the sub module number of MMC is more, the test of MMC controller will cost more time and effort. Hardware in the loop test based on real time simulator will save a lot of time and money caused by the MMC test. And due to the flexible of HIL, it becomes more and more popular in the industry area. The MMC modelling method remains an important issue for the MMC HIL test. Specifically, the VSC model should realistically reflect the nonlinear device switching characteristics, switching and conduction losses, tailing current, and diode reverse recovery behaviour of a realistic converter. In this paper, an IGBT switching characteristic curve embedded half-bridge MMC modelling method is proposed. This method is based on the switching curve referring and sample circuit calculation, and it is sample for implementation. Based on the proposed method, a FPGA real time simulation is carried out with 200ns sample time. The real time simulation results show the proposed method is correct.

  16. Realistic 3D Terrain Roaming and Real-Time Flight Simulation

    Science.gov (United States)

    Que, Xiang; Liu, Gang; He, Zhenwen; Qi, Guang

    2014-12-01

    This paper presents an integrate method, which can provide access to current status and the dynamic visible scanning topography, to enhance the interactive during the terrain roaming and real-time flight simulation. A digital elevation model and digital ortho-photo map data integrated algorithm is proposed as the base algorithm for our approach to build a realistic 3D terrain scene. A new technique with help of render to texture and head of display for generating the navigation pane is used. In the flight simulating, in order to eliminate flying "jump", we employs the multidimensional linear interpolation method to adjust the camera parameters dynamically and steadily. Meanwhile, based on the principle of scanning laser imaging, we draw pseudo color figures by scanning topography in different directions according to the real-time flying status. Simulation results demonstrate that the proposed algorithm is prospective for applications and the method can improve the effect and enhance dynamic interaction during the real-time flight.

  17. Real-time graphics for the Space Station Freedom cupola, developed in the Systems Engineering Simulator

    Science.gov (United States)

    Red, Michael T.; Hess, Philip W.

    1989-01-01

    Among the Lyndon B. Johnson Space Center's responsibilities for Space Station Freedom is the cupola. Attached to the resource node, the cupola is a windowed structure that will serve as the space station's secondary control center. From the cupola, operations involving the mobile service center and orbital maneuvering vehicle will be conducted. The Systems Engineering Simulator (SES), located in building 16, activated a real-time man-in-the-loop cupola simulator in November 1987. The SES cupola is an engineering tool with the flexibility to evolve in both hardware and software as the final cupola design matures. Two workstations are simulated with closed-circuit television monitors, rotational and translational hand controllers, programmable display pushbuttons, and graphics display with trackball and keyboard. The displays and controls of the SES cupola are driven by a Silicon Graphics Integrated Raster Imaging System (IRIS) 4D/70 GT computer. Through the use of an interactive display builder program, SES, cupola display pages consisting of two dimensional and three dimensional graphics are constructed. These display pages interact with the SES via the IRIS real-time graphics interface. The focus is on the real-time graphics interface applications software developed on the IRIS.

  18. Real-time simulator for designing electron dual scattering foil systems.

    Science.gov (United States)

    Carver, Robert L; Hogstrom, Kenneth R; Price, Michael J; LeBlanc, Justin D; Pitcher, Garrett M

    2014-11-08

    The purpose of this work was to develop a user friendly, accurate, real-time com- puter simulator to facilitate the design of dual foil scattering systems for electron beams on radiotherapy accelerators. The simulator allows for a relatively quick, initial design that can be refined and verified with subsequent Monte Carlo (MC) calculations and measurements. The simulator also is a powerful educational tool. The simulator consists of an analytical algorithm for calculating electron fluence and X-ray dose and a graphical user interface (GUI) C++ program. The algorithm predicts electron fluence using Fermi-Eyges multiple Coulomb scattering theory with the reduced Gaussian formalism for scattering powers. The simulator also estimates central-axis and off-axis X-ray dose arising from the dual foil system. Once the geometry of the accelerator is specified, the simulator allows the user to continuously vary primary scattering foil material and thickness, secondary scat- tering foil material and Gaussian shape (thickness and sigma), and beam energy. The off-axis electron relative fluence or total dose profile and central-axis X-ray dose contamination are computed and displayed in real time. The simulator was validated by comparison of off-axis electron relative fluence and X-ray percent dose profiles with those calculated using EGSnrc MC. Over the energy range 7-20 MeV, using present foils on an Elekta radiotherapy accelerator, the simulator was able to reproduce MC profiles to within 2% out to 20 cm from the central axis. The central-axis X-ray percent dose predictions matched measured data to within 0.5%. The calculation time was approximately 100 ms using a single Intel 2.93 GHz processor, which allows for real-time variation of foil geometrical parameters using slider bars. This work demonstrates how the user-friendly GUI and real-time nature of the simulator make it an effective educational tool for gaining a better understanding of the effects that various system

  19. Real-Time Impact Visualization Inspection of Aerospace Composite Structures with Distributed Sensors.

    Science.gov (United States)

    Si, Liang; Baier, Horst

    2015-07-08

    For the future design of smart aerospace structures, the development and application of a reliable, real-time and automatic monitoring and diagnostic technique is essential. Thus, with distributed sensor networks, a real-time automatic structural health monitoring (SHM) technique is designed and investigated to monitor and predict the locations and force magnitudes of unforeseen foreign impacts on composite structures and to estimate in real time mode the structural state when impacts occur. The proposed smart impact visualization inspection (IVI) technique mainly consists of five functional modules, which are the signal data preprocessing (SDP), the forward model generator (FMG), the impact positioning calculator (IPC), the inverse model operator (IMO) and structural state estimator (SSE). With regard to the verification of the practicality of the proposed IVI technique, various structure configurations are considered, which are a normal CFRP panel and another CFRP panel with "orange peel" surfaces and a cutout hole. Additionally, since robustness against several background disturbances is also an essential criterion for practical engineering demands, investigations and experimental tests are carried out under random vibration interfering noise (RVIN) conditions. The accuracy of the predictions for unknown impact events on composite structures using the IVI technique is validated under various structure configurations and under changing environmental conditions. The evaluated errors all fall well within a satisfactory limit range. Furthermore, it is concluded that the IVI technique is applicable for impact monitoring, diagnosis and assessment of aerospace composite structures in complex practical engineering environments.

  20. Real-Time Climate Simulations in the Interactive 3D Game Universe Sandbox ²

    Science.gov (United States)

    Goldenson, N. L.

    2014-12-01

    Exploration in an open-ended computer game is an engaging way to explore climate and climate change. Everyone can explore physical models with real-time visualization in the educational simulator Universe Sandbox ² (universesandbox.com/2), which includes basic climate simulations on planets. I have implemented a time-dependent, one-dimensional meridional heat transport energy balance model to run and be adjustable in real time in the midst of a larger simulated system. Universe Sandbox ² is based on the original game - at its core a gravity simulator - with other new physically-based content for stellar evolution, and handling collisions between bodies. Existing users are mostly science enthusiasts in informal settings. We believe that this is the first climate simulation to be implemented in a professionally developed computer game with modern 3D graphical output in real time. The type of simple climate model we've adopted helps us depict the seasonal cycle and the more drastic changes that come from changing the orbit or other external forcings. Users can alter the climate as the simulation is running by altering the star(s) in the simulation, dragging to change orbits and obliquity, adjusting the climate simulation parameters directly or changing other properties like CO2 concentration that affect the model parameters in representative ways. Ongoing visuals of the expansion and contraction of sea ice and snow-cover respond to the temperature calculations, and make it accessible to explore a variety of scenarios and intuitive to understand the output. Variables like temperature can also be graphed in real time. We balance computational constraints with the ability to capture the physical phenomena we wish to visualize, giving everyone access to a simple open-ended meridional energy balance climate simulation to explore and experiment with. The software lends itself to labs at a variety of levels about climate concepts including seasons, the Greenhouse effect

  1. Online Synchrophasor-Based Dynamic State Estimation using Real-Time Digital Simulator

    DEFF Research Database (Denmark)

    Khazraj, Hesam; Adewole, Adeyemi Charles; Udaya, Annakkage

    2018-01-01

    Dynamic state estimation is a very important control center application used in the dynamic monitoring of state variables. This paper presents and validates a time-synchronized phasor measurement unit (PMU)-based for dynamic state estimation by unscented Kalman filter (UKF) method using the real-...... using the RTDS (real-time digital simulator). The dynamic state variables of multi-machine systems are monitored and measured for the study on the transient behavior of power systems.......Dynamic state estimation is a very important control center application used in the dynamic monitoring of state variables. This paper presents and validates a time-synchronized phasor measurement unit (PMU)-based for dynamic state estimation by unscented Kalman filter (UKF) method using the real......-time digital simulator (RTDS). The dynamic state variables of the system are the rotor angle and speed of the generators. The performance of the UKF method is tested with PMU measurements as inputs using the IEEE 14-bus test system. This test system was modeled in the RSCAD software and tested in real time...

  2. A new approach in simulating RF linacs using a general, linear real-time signal processor

    International Nuclear Information System (INIS)

    Young, A.; Jachim, S.P.

    1991-01-01

    Strict requirements on the tolerances of the amplitude and phase of the radio frequency (RF) cavity field are necessary to advance the field of accelerator technology. Due to these stringent requirements upon modern accelerators,a new approach of modeling and simulating is essential in developing and understanding their characteristics. This paper describes the implementation of a general, linear model of an RF cavity which is used to develop a real-time signal processor. This device fully emulates the response of an RF cavity upon receiving characteristic parameters (Q 0 , ω 0 , Δω, R S , Z 0 ). Simulating an RF cavity with a real-time signal processor is beneficial to an accelerator designer because the device allows one to answer fundamental questions on the response of the cavity to a particular stimulus without operating the accelerator. In particular, the complex interactions between the RF power and the control systems, the beam and cavity fields can simply be observed in a real-time domain. The signal processor can also be used upon initialization of the accelerator as a diagnostic device and as a dummy load for determining the closed-loop error of the control system. In essence, the signal processor is capable of providing information that allows an operator to determine whether the control systems and peripheral devices are operating properly without going through the tedious procedure of running the beam through a cavity

  3. Design of a real-time wind turbine simulator using a custom parallel architecture

    Science.gov (United States)

    Hoffman, John A.; Gluck, R.; Sridhar, S.

    1995-01-01

    The design of a new parallel-processing digital simulator is described. The new simulator has been developed specifically for analysis of wind energy systems in real time. The new processor has been named: the Wind Energy System Time-domain simulator, version 3 (WEST-3). Like previous WEST versions, WEST-3 performs many computations in parallel. The modules in WEST-3 are pure digital processors, however. These digital processors can be programmed individually and operated in concert to achieve real-time simulation of wind turbine systems. Because of this programmability, WEST-3 is very much more flexible and general than its two predecessors. The design features of WEST-3 are described to show how the system produces high-speed solutions of nonlinear time-domain equations. WEST-3 has two very fast Computational Units (CU's) that use minicomputer technology plus special architectural features that make them many times faster than a microcomputer. These CU's are needed to perform the complex computations associated with the wind turbine rotor system in real time. The parallel architecture of the CU causes several tasks to be done in each cycle, including an IO operation and the combination of a multiply, add, and store. The WEST-3 simulator can be expanded at any time for additional computational power. This is possible because the CU's interfaced to each other and to other portions of the simulation using special serial buses. These buses can be 'patched' together in essentially any configuration (in a manner very similar to the programming methods used in analog computation) to balance the input/ output requirements. CU's can be added in any number to share a given computational load. This flexible bus feature is very different from many other parallel processors which usually have a throughput limit because of rigid bus architecture.

  4. Secure environment for real-time tele-collaboration on virtual simulation of radiation treatment planning.

    Science.gov (United States)

    Ntasis, Efthymios; Maniatis, Theofanis A; Nikita, Konstantina S

    2003-01-01

    A secure framework is described for real-time tele-collaboration on Virtual Simulation procedure of Radiation Treatment Planning. An integrated approach is followed clustering the security issues faced by the system into organizational issues, security issues over the LAN and security issues over the LAN-to-LAN connection. The design and the implementation of the security services are performed according to the identified security requirements, along with the need for real time communication between the collaborating health care professionals. A detailed description of the implementation is given, presenting a solution, which can directly be tailored to other tele-collaboration services in the field of health care. The pilot study of the proposed security components proves the feasibility of the secure environment, and the consistency with the high performance demands of the application.

  5. Simulation Study of Real Time 3-D Synthetic Aperture Sequential Beamforming for Ultrasound Imaging

    DEFF Research Database (Denmark)

    Hemmsen, Martin Christian; Rasmussen, Morten Fischer; Stuart, Matthias Bo

    2014-01-01

    in the main system. The real-time imaging capability is achieved using a synthetic aperture beamforming technique, utilizing the transmit events to generate a set of virtual elements that in combination can generate an image. The two core capabilities in combination is named Synthetic Aperture Sequential......This paper presents a new beamforming method for real-time three-dimensional (3-D) ultrasound imaging using a 2-D matrix transducer. To obtain images with sufficient resolution and contrast, several thousand elements are needed. The proposed method reduces the required channel count from...... Beamforming (SASB). Simulations are performed to evaluate the image quality of the presented method in comparison to Parallel beamforming utilizing 16 receive beamformers. As indicators for image quality the detail resolution and Cystic resolution are determined for a set of scatterers at a depth of 90mm...

  6. Applications of parallel computer architectures to the real-time simulation of nuclear power systems

    International Nuclear Information System (INIS)

    Doster, J.M.; Sills, E.D.

    1988-01-01

    In this paper the authors report on efforts to utilize parallel computer architectures for the thermal-hydraulic simulation of nuclear power systems and current research efforts toward the development of advanced reactor operator aids and control systems based on this new technology. Many aspects of reactor thermal-hydraulic calculations are inherently parallel, and the computationally intensive portions of these calculations can be effectively implemented on modern computers. Timing studies indicate faster-than-real-time, high-fidelity physics models can be developed when the computational algorithms are designed to take advantage of the computer's architecture. These capabilities allow for the development of novel control systems and advanced reactor operator aids. Coupled with an integral real-time data acquisition system, evolving parallel computer architectures can provide operators and control room designers improved control and protection capabilities. Current research efforts are currently under way in this area

  7. [Research progress on real-time deformable models of soft tissues for surgery simulation].

    Science.gov (United States)

    Xu, Shaoping; Liu, Xiaoping; Zhang, Hua; Luo, Jie

    2010-04-01

    Biological tissues generally exhibit nonlinearity, anisotropy, quasi-incompressibility and viscoelasticity about material properties. Simulating the behaviour of elastic objects in real time is one of the current objectives of virtual surgery simulation which is still a challenge for researchers to accurately depict the behaviour of human tissues. In this paper, we present a classification of the different deformable models that have been developed. We present the advantages and disadvantages of each one. Finally, we make a comparison of deformable models and perform an evaluation of the state of the art and the future of deformable models.

  8. Real-time simulation of energy management in a domestic consumer

    DEFF Research Database (Denmark)

    Fernandes, F.; Silva, M.; Faria, P.

    2013-01-01

    Recent and future changes in power systems, mainly in the smart grid operation context, are related to a high complexity of power networks operation. This leads to more complex communications and to higher network elements monitoring and control levels, both from network’s and consumers’ standpoi......-time simulation from Opal RT. This makes possible the integration of Matlab®/Simulink® real-time simulation models. The main goal of the present paper is to compare the advantages of the resulting improved system, while managing the energy consumption of a domestic consumer....

  9. Real-Time Simulation of Aeroheating of the Hyper-X Airplane

    Science.gov (United States)

    Gong, Les

    2005-01-01

    A capability for real-time computational simulation of aeroheating has been developed in support of the Hyper-X program, which is directed toward demonstrating the feasibility of operating an air-breathing ramjet/scramjet engine at mach 5, mach 7, and mach 10. The simulation software will serve as a valuable design tool for initial trajectory studies in which aerodynamic heating is expected to exert a major influence in the design of the Hyper-X airplane; this tool will aid in the selection of materials, sizing of structural skin thicknesses, and selection of components of a thermal-protection system (TPS) for structures that must be insulated against aeroheating.

  10. Co-simulation for real time safety verification of nuclear power plants

    International Nuclear Information System (INIS)

    Boafo, E.K.; Zhang, L.; Nasimi, E.; Gabbar, H.A.

    2015-01-01

    Small and major accidents and near misses are still occurring in nuclear power plants (NPPs). Risk level has increased with the degradation of NPP equipment and instrumentations. In order to achieve NPP safety, it is important to continuously evaluate risk for all potential hazard and fault propagation scenarios and map protection layers to fault / failure / hazard propagation scenarios to be able to evaluate and verify safety level during NPP operation. There are major limitations in current real time safety verification tools, as it is mainly offline and with no integration to NPP simulation tools. The main goal of this research is to develop real time safety verification with co-simulation tool to be integrated with plant operation support systems. This includes the development of static and dynamic fault semantic network (FSN) to model all possible fault propagation scenarios and the interrelationships among associated process variables. Safety and protection layers along with their reliability are mapped to FSN so that safety levels can be verified during plant operation. Errors between multiphysics models and real time data are modeled to accurately and dynamically tune FSN for each fault propagation scenario. The detailed methodology will show how to integrate process models, construction of static FSN with fault propagation scenarios, and evaluation and tuning of dynamic FSN with probabilistic and process variable interaction values. Principle Component Analysis method is used reduce dimensionality and reduce process variables associated with each fault scenario. Then map independent protection layers (IPL) to FSN with estimated reliability measures of each protection layer to accurately verify safety for different operational scenarios. Intelligent algorithms is used with multivariate techniques to accurate define the interrelation among process variables, in terms of signal strength and time delay, using Genetic Programming (GP), which will provide basis

  11. Estimate of the real-time respiratory simulation system in cyberknife image-guided radiosurgery

    International Nuclear Information System (INIS)

    Min, Chul Kee; Chung, Weon Kuu; Lee, Suk

    2010-01-01

    The purpose of this study was to evaluate the target accuracy according to the movement with respiration of an actual patient in a quantitative way by developing a real-time respiratory simulation system (RRSS), including a patient customized 3D moving phantom. The real-time respiratory simulation system (RRSS) consists of two robots in order to implement both the movement of body surfaces and the movement of internal organs caused by respiration. The quantitative evaluation for the 3D movement of the RRSS was performed using a real-time laser displacement sensor for each axis. The average difference in the static movement of the RRSS was about 0.01 ∼ 0.06 mm. Also, in the evaluation of the dynamic movement by producing a formalized sine wave with the phase of four seconds per cycle, the difference between the measured and the calculated values for each cycle length in the robot that was in charge of body surfaces and the robot that was in charge of the movement of internal tumors showed 0.10 ∼ 0.55 seconds, and the correlation coefficients between the calculated and the measured values were 0.998 ∼ 0.999. The differences between the maximum and the minimum amplitudes were 0.01 ∼ 0.06 mm, and the reproducibility was within ±0.5 mm. In the case of the application and non-application of respiration, the target errors were -0.05 ∼ 1.05 mm and -0.13 ∼ 0.74 mm, respectively, and the entire target errors were 1.30 mm and 0.79 mm, respectively. Based on the accuracy in the RRSS system, various respiration patterns of patients can be reproduced in real-time. Also, this system can be used as an optimal tool for applying patient customized accuracy management in image-guided radiosurgery.

  12. Estimate of the real-time respiratory simulation system in cyberknife image-guided radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Min, Chul Kee [Konyang Univ. Hospital, Daejeon (Korea, Republic of); Kyonggi University, Seoul (Korea, Republic of); Chung, Weon Kuu [Konyang Univ. Hospital, Daejeon (Korea, Republic of); Lee, Suk [Korea University, Seoul (Korea, Republic of); and others

    2010-01-15

    The purpose of this study was to evaluate the target accuracy according to the movement with respiration of an actual patient in a quantitative way by developing a real-time respiratory simulation system (RRSS), including a patient customized 3D moving phantom. The real-time respiratory simulation system (RRSS) consists of two robots in order to implement both the movement of body surfaces and the movement of internal organs caused by respiration. The quantitative evaluation for the 3D movement of the RRSS was performed using a real-time laser displacement sensor for each axis. The average difference in the static movement of the RRSS was about 0.01 {approx} 0.06 mm. Also, in the evaluation of the dynamic movement by producing a formalized sine wave with the phase of four seconds per cycle, the difference between the measured and the calculated values for each cycle length in the robot that was in charge of body surfaces and the robot that was in charge of the movement of internal tumors showed 0.10 {approx} 0.55 seconds, and the correlation coefficients between the calculated and the measured values were 0.998 {approx} 0.999. The differences between the maximum and the minimum amplitudes were 0.01 {approx} 0.06 mm, and the reproducibility was within {+-}0.5 mm. In the case of the application and non-application of respiration, the target errors were -0.05 {approx} 1.05 mm and -0.13 {approx} 0.74 mm, respectively, and the entire target errors were 1.30 mm and 0.79 mm, respectively. Based on the accuracy in the RRSS system, various respiration patterns of patients can be reproduced in real-time. Also, this system can be used as an optimal tool for applying patient customized accuracy management in image-guided radiosurgery.

  13. Distributed Coordination of Electric Vehicle Charging in a Community Microgrid Considering Real-Time Price

    DEFF Research Database (Denmark)

    Li, Chendan; Schaltz, Erik; Quintero, Juan Carlos Vasquez

    2016-01-01

    The predictable increasing adoption of EV by residential users imposes the necessity of Electric Vehicle charging coordination, in order to charge effectively while minimizing the impact on the grid. In this paper, a two-stage distributed coordination algorithm for electric vehicle charging...... management in a community microgrid is proposed. Each local EV charging controller is taken as an agent, which can manage the charging to achieve the optimization of the whole community by communicating in a sparse network. The proposed algorithm aims at optimizing real-time, which manages the charging...

  14. Nanoimprinted distributed feedback dye laser sensor for real-time imaging of small molecule diffusion

    DEFF Research Database (Denmark)

    Vannahme, Christoph; Dufva, Martin; Kristensen, Anders

    2014-01-01

    Label-free imaging is a promising tool for the study of biological processes such as cell adhesion and small molecule signaling processes. In order to image in two dimensions of space current solutions require motorized stages which results in low imaging frame rates. Here, a highly sensitive...... distributed feedback (DFB) dye laser sensor for real-time label-free imaging without any moving parts enabling a frame rate of 12 Hz is presented. The presence of molecules on the laser surface results in a wavelength shift which is used as sensor signal. The unique DFB laser structure comprises several areas...

  15. Design of Mixed-Criticality Applications on Distributed Real-Time Systems

    DEFF Research Database (Denmark)

    Tamas-Selicean, Domitian

    the concept of virtual links, and temporal separation, enforced through schedule tables for TT messages and bandwidth allocation for RC messages. The objective of this thesis is to develop methods and tools for distributed mixed-criticality real-time systems. At the processor level, we are interested......A mixed-criticality system implements applications of different safety-criticality levels onto the same platform. In such cases, the certification standards require that applications of different criticality levels are protected so they cannot influence each other. Otherwise, all tasks have...

  16. Real-time simulation of contact and cutting of heterogeneous soft-tissues.

    Science.gov (United States)

    Courtecuisse, Hadrien; Allard, Jérémie; Kerfriden, Pierre; Bordas, Stéphane P A; Cotin, Stéphane; Duriez, Christian

    2014-02-01

    This paper presents a numerical method for interactive (real-time) simulations, which considerably improves the accuracy of the response of heterogeneous soft-tissue models undergoing contact, cutting and other topological changes. We provide an integrated methodology able to deal both with the ill-conditioning issues associated with material heterogeneities, contact boundary conditions which are one of the main sources of inaccuracies, and cutting which is one of the most challenging issues in interactive simulations. Our approach is based on an implicit time integration of a non-linear finite element model. To enable real-time computations, we propose a new preconditioning technique, based on an asynchronous update at low frequency. The preconditioner is not only used to improve the computation of the deformation of the tissues, but also to simulate the contact response of homogeneous and heterogeneous bodies with the same accuracy. We also address the problem of cutting the heterogeneous structures and propose a method to update the preconditioner according to the topological modifications. Finally, we apply our approach to three challenging demonstrators: (i) a simulation of cataract surgery (ii) a simulation of laparoscopic hepatectomy (iii) a brain tumor surgery. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. A prototype percutaneous transhepatic cholangiography training simulator with real-time breathing motion.

    Science.gov (United States)

    Villard, P F; Vidal, F P; Hunt, C; Bello, F; John, N W; Johnson, S; Gould, D A

    2009-11-01

    We present here a simulator for interventional radiology focusing on percutaneous transhepatic cholangiography (PTC). This procedure consists of inserting a needle into the biliary tree using fluoroscopy for guidance. The requirements of the simulator have been driven by a task analysis. The three main components have been identified: the respiration, the real-time X-ray display (fluoroscopy) and the haptic rendering (sense of touch). The framework for modelling the respiratory motion is based on kinematics laws and on the Chainmail algorithm. The fluoroscopic simulation is performed on the graphic card and makes use of the Beer-Lambert law to compute the X-ray attenuation. Finally, the haptic rendering is integrated to the virtual environment and takes into account the soft-tissue reaction force feedback and maintenance of the initial direction of the needle during the insertion. Five training scenarios have been created using patient-specific data. Each of these provides the user with variable breathing behaviour, fluoroscopic display tuneable to any device parameters and needle force feedback. A detailed task analysis has been used to design and build the PTC simulator described in this paper. The simulator includes real-time respiratory motion with two independent parameters (rib kinematics and diaphragm action), on-line fluoroscopy implemented on the Graphics Processing Unit and haptic feedback to feel the soft-tissue behaviour of the organs during the needle insertion.

  18. TRSM-a thermal-hydraulic real-time simulation model for PWR

    International Nuclear Information System (INIS)

    Zhou Weichang

    1997-01-01

    TRSM (a Thermal-hydraulic Real-time Simulation Model) has been developed for PWR real-time simulation and best-estimate prediction of normal operating and abnormal accident conditions. It is a non-equilibrium two phase flow thermal-hydraulic model based on five basic conservation equations. A drift flux model is used to account for the unequal velocities of liquid and gaseous mixture, with or without the presence of the noncondensibles. Critical flow models are applied for break flow and valve flow calculations. A 5-regime two phase heat convection model is applied for clad-to-coolant as well as fluid-to-tubing heat transfer. A rigorous reactor coolant pump model is used to calculate the pressure drop and rise for the suction and discharge ends with complete pump characteristics curves included. The TRSM model has been adapted in the full-scale training simulator of Qinshan Nuclear Power Plant 300 MW unit to simulate the thermal-hydraulic performance of the NSSS. The simulation results of a cold leg LOCA and a steam generator tube rupture (SGTR) accident are presented

  19. Multi-level Simulation of a Real Time Vibration Monitoring System Component

    Science.gov (United States)

    Robertson, Bryan A.; Wilkerson, Delisa

    2005-01-01

    This paper describes the development of a custom built Digital Signal Processing (DSP) printed circuit board designed to implement the Advanced Real Time Vibration Monitoring Subsystem proposed by Marshall Space Flight Center (MSFC) Transportation Directorate in 2000 for the Space Shuttle Main Engine Advanced Health Management System (AHMS). This Real Time Vibration Monitoring System (RTVMS) is being developed for ground use as part of the AHMS Health Management Computer-Integrated Rack Assembly (HMC-IRA). The HMC-IRA RTVMS design contains five DSPs which are highly interconnected through individual communication ports, shared memory, and a unique communication router that allows all the DSPs to receive digitized data fiom two multi-channel analog boards simultaneously. This paper will briefly cover the overall board design but will focus primarily on the state-of-the-art simulation environment within which this board was developed. This 16-layer board with over 1800 components and an additional mezzanine card has been an extremely challenging design. Utilization of a Mentor Graphics simulation environment provided the unique board and system level simulation capability to ascertain any timing or functional concerns before production. By combining VHDL, Synopsys Software and Hardware Models, and the Mentor Design Capture Environment, multiple simulations were developed to verify the RTVMS design. This multi-level simulation allowed the designers to achieve complete operability without error the first time the RTVMS printed circuit board was powered. The HMC-IRA design has completed all engineering and deliverable unit testing. P

  20. Power system analysis of Hanlim superconducting HVDC system using real time digital simulator

    International Nuclear Information System (INIS)

    Won, Y.J.; Kim, J.G.; Kim, A.R.; Kim, G.H.; Park, M.; Yu, I.K.; Sim, K.D.; Cho, J.; Lee, S.; Jeong, K.W.; Watanabe, K.

    2011-01-01

    KEPCO has planned to construct a test site for renewable energy in Jeju power system. One kilometer length of total 8 km was designed as superconducting DC cable. We have developed a simulation model of the 8 km HVDC system using real time digital simulator. The simulation result shows that the HVDC line was not affected by wind power variation. Jeju island is located approximately 100 km south from the mainland of Korea, and had a peak load of about 553 MW in 2008. The demand increases 7.2% a year over the last 5 years. Since the wind profiles of Jeju island are more favorable than mainland of Korea, many companies have shown interest in the wind power business at the Jeju island. Moreover KEPCO has a plan for renewable energy test too whose power will be delivered by HVDC system. One kilometer length of total 8 km was designed as superconducting DC cable. Rest 7 km will be the conventional overhead line. In this paper, the authors have developed a simulation model of the power network around 8 km HVDC system using real time digital simulator (RTDS).

  1. Simulation model for transcervical laryngeal injection providing real-time feedback.

    Science.gov (United States)

    Ainsworth, Tiffiny A; Kobler, James B; Loan, Gregory J; Burns, James A

    2014-12-01

    This study aimed to develop and evaluate a model for teaching transcervical laryngeal injections. A 3-dimensional printer was used to create a laryngotracheal framework based on de-identified computed tomography images of a human larynx. The arytenoid cartilages and intrinsic laryngeal musculature were created in silicone from clay casts and thermoplastic molds. The thyroarytenoid (TA) muscle was created with electrically conductive silicone using metallic filaments embedded in silicone. Wires connected TA muscles to an electrical circuit incorporating a cell phone and speaker. A needle electrode completed the circuit when inserted in the TA during simulated injection, providing real-time feedback of successful needle placement by producing an audible sound. Face validation by the senior author confirmed appropriate tactile feedback and anatomical realism. Otolaryngologists pilot tested the model and completed presimulation and postsimulation questionnaires. The high-fidelity simulation model provided tactile and audio feedback during needle placement, simulating transcervical vocal fold injections. Otolaryngology residents demonstrated higher comfort levels with transcervical thyroarytenoid injection on postsimulation questionnaires. This is the first study to describe a simulator for developing transcervical vocal fold injection skills. The model provides real-time tactile and auditory feedback that aids in skill acquisition. Otolaryngologists reported increased confidence with transcervical injection after using the simulator. © The Author(s) 2014.

  2. High resolution real time capable combustion chamber simulation; Zeitlich hochaufloesende echtzeitfaehige Brennraumsimulation

    Energy Technology Data Exchange (ETDEWEB)

    Piewek, J. [Volkswagen AG, Wolfsburg (Germany)

    2008-07-01

    The article describes a zero-dimensional model for the real time capable combustion chamber pressure calculation with analogue pressure sensor output. The closed-loop-operation of an Engine Control Unit is shown at the hardware-in-the-loop-simulator (HiL simulator) for a 4-cylinder common rail diesel engine. The presentation of the model focuses on the simulation of the load variation which does not depend on the injection system and thus the simulated heat release rate. Particular attention is paid to the simulation and the resulting test possibilities regarding to full-variable valve gears. It is shown that black box models consisting in the HiL mean value model for the aspirated gas mass, the exhaust gas temperature after the outlet valve and the mean indicated pressure can be replaced by calculations from the high-resolution combustion chamber model. (orig.)

  3. Real time simulation of the release and transport of radioactive contaminants

    International Nuclear Information System (INIS)

    Popa, F.; Weber, M.

    1991-01-01

    Calculating the responses of the radiation monitoring system (RMS) remains one of the most difficult aspects of nuclear power plant simulation to bring into the post-TMI, first principles simulator era. This task requires the simulation of the transport of radioactive contaminants, the transport of the radiation itself, and the instrument channel including the detector. The complex physics and lack of knowledge of input parameters have made these models lag the general simulator trend away from logical/heuristic modeling of physical systems. This paper describes a series of advances to the modeling methodology to change this situation. The objective in the design of this real time simulation model was to always calculate qualitatively reasonable radiation detector readings

  4. A distributed approach for optimizing cascaded classifier topologies in real-time stream mining systems.

    Science.gov (United States)

    Foo, Brian; van der Schaar, Mihaela

    2010-11-01

    In this paper, we discuss distributed optimization techniques for configuring classifiers in a real-time, informationally-distributed stream mining system. Due to the large volume of streaming data, stream mining systems must often cope with overload, which can lead to poor performance and intolerable processing delay for real-time applications. Furthermore, optimizing over an entire system of classifiers is a difficult task since changing the filtering process at one classifier can impact both the feature values of data arriving at classifiers further downstream and thus, the classification performance achieved by an ensemble of classifiers, as well as the end-to-end processing delay. To address this problem, this paper makes three main contributions: 1) Based on classification and queuing theoretic models, we propose a utility metric that captures both the performance and the delay of a binary filtering classifier system. 2) We introduce a low-complexity framework for estimating the system utility by observing, estimating, and/or exchanging parameters between the inter-related classifiers deployed across the system. 3) We provide distributed algorithms to reconfigure the system, and analyze the algorithms based on their convergence properties, optimality, information exchange overhead, and rate of adaptation to non-stationary data sources. We provide results using different video classifier systems.

  5. Development of an advanced real time simulation tool, ARTIST and its verification

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hee Cheol; Moon, S. K.; Yoon, B. J.; Sim, S. K.; Lee, W. J. [Korea Atomic Energy Research Institute, Taejeon (Korea)

    1999-10-01

    A real time reactor system analysis code ARTIST, based on drift flux model has been developed to investigate the transient system behavior under low pressure, low flow and low power conditions with noncondensable gas present in the system. The governing equations of the ARTIST code consist of three mass continuity equations (steam, liquid and noncondensables), two energy equations (steam and mixture) and one mixture equation constituted with the drift flux model. The drift flux model of ARTIST has been validated against the THETIS experimental data by comparing the void distribution in the system. Especially, the calculated void fraction by Chexal-Lellouche void fraction correlation at low pressure and low flow, is better than the results of both the homogeneous model of TASS code and the two-fluid model of RELAP5/MOD3 code. When noncondensable gas exists, thermal-hydraulic state solution scheme and the calculation methods of the partial derivatives are developed. Numerical consistency and convergence was tested with the one volume problems and the manometric oscillation was assessed to examine the calculation methods of the partial derivatives. Calculated thermal-hydraulic state for each test shows the consistent and expected behaviour. In order to evaluate the ARTIST code capability in predicting the two phase thermal-hydraulic phenomena of the loss of RHR accident during midloop operation, BETHSY test 6.9d is simulated. From the results, it is judged that the reflux condensation model and the critical flow model for the noncondensable gas are necessary to correctly predict the thermal-hydraulic behaviour. Finally, the verification run was performed without the drift flux model and the noncondensable gas model for the postulated accidents of the real plants. The ARTIST code well reproduces the parametric trends which are calculated by TASS code. Therefore, the integrity of ARTIST code was verified. 35 refs., 70 figs., 3 tabs. (Author)

  6. Development and Validation in Air Traffic Control by Means of Real-Time Simulations

    Directory of Open Access Journals (Sweden)

    Stephan Herr

    2009-02-01

    Full Text Available The airspace in Central Europe is already one of the busiest airspaces in the world and the forecasts predict further traffic increases. The current air transport system is reaching its capacity limits, not only at airports but also in parts of the en-route area. This is mainly due to the workload constraints of air traffic controllers. In the past, many technical system functionalities were developed with the aim of reducing controller workload and thus enabling the safe handling of the predicted traffic growth. But these new functionalities alone will not provide adequate relief to air traffic controllers. Their working procedures and the airspace structure will have to be adapted accordingly. In order to obtain real operational benefits, these technical innovations must be integrated into an overall concept which – in addition to the above-mentioned factors – also takes account of ergonomic aspects and human-machine interfaces. When developing such an overall concept, additional evaluation and validation measures are indispensable to ensure that the desired operational benefits are achieved. This is why DFS has for many years used fast- and real-time simulations to assess and optimise any changes to be made to the air traffic control system. The working methods of DFS in this context are in keeping with the European Operational Concept Validation Methodology of 2007, in short E-OCVM. This paper outlines the development and validation activities of DFS using the MSP D/L project as an example. The project deals with the introduction of the new role of air traffic controllers as multi-sector planners (MSP and new system functionalities, such as air/ground data link (D/L. The project included the development of an operational concept for using the new functionalities as well as for defining working procedures and the airspace structure. This concept was subsequently evaluated by means of a fast-time simulation and two real-time simulations

  7. An FPGA Platform for Real-Time Simulation of Spiking Neuronal Networks.

    Science.gov (United States)

    Pani, Danilo; Meloni, Paolo; Tuveri, Giuseppe; Palumbo, Francesca; Massobrio, Paolo; Raffo, Luigi

    2017-01-01

    In the last years, the idea to dynamically interface biological neurons with artificial ones has become more and more urgent. The reason is essentially due to the design of innovative neuroprostheses where biological cell assemblies of the brain can be substituted by artificial ones. For closed-loop experiments with biological neuronal networks interfaced with in silico modeled networks, several technological challenges need to be faced, from the low-level interfacing between the living tissue and the computational model to the implementation of the latter in a suitable form for real-time processing. Field programmable gate arrays (FPGAs) can improve flexibility when simple neuronal models are required, obtaining good accuracy, real-time performance, and the possibility to create a hybrid system without any custom hardware, just programming the hardware to achieve the required functionality. In this paper, this possibility is explored presenting a modular and efficient FPGA design of an in silico spiking neural network exploiting the Izhikevich model. The proposed system, prototypically implemented on a Xilinx Virtex 6 device, is able to simulate a fully connected network counting up to 1,440 neurons, in real-time, at a sampling rate of 10 kHz, which is reasonable for small to medium scale extra-cellular closed-loop experiments.

  8. A flexible hydrological warning system in Denmark for real-time surface water and groundwater simulations

    Science.gov (United States)

    He, Xin; Stisen, Simon; Wiese, Marianne B.; Jørgen Henriksen, Hans

    2015-04-01

    In Denmark, increasing focus on extreme weather events has created considerable demand for short term forecasts and early warnings in relation to groundwater and surface water flooding. The Geological Survey of Denmark and Greenland (GEUS) has setup, calibrated and applied a nationwide water resources model, the DK-Model, primarily for simulating groundwater and surface water flows and groundwater levels during the past 20 years. So far, the DK-model has only been used in offline historical and future scenario simulations. Therefore, challenges arise in operating such a model for online forecasts and early warnings, which requires access to continuously updated observed climate input data and forecast data of precipitation, temperature and global radiation for the next 48 hours or longer. GEUS has a close collaboration with the Danish Meteorological Institute in order to test and enable this data input for the DK model. Due to the comprehensive physical descriptions of the DK-Model, the simulation results can potentially be any component of the hydrological cycle within the models domain. Therefore, it is important to identify which results need to be updated and saved in the real-time mode, since it is not computationally economical to save every result considering the heavy load of data. GEUS have worked closely with the end-users and interest groups such as water planners and emergency managers from the municipalities, water supply and waste water companies, consulting companies and farmer organizations, in order to understand their possible needs for real time simulation and monitoring of the nationwide water cycle. This participatory process has been supported by a web based questionnaire survey, and a workshop that connected the model developers and the users. For qualifying the stakeholder engagement, GEUS has selected a representative catchment area (Skjern River) for testing and demonstrating a prototype of the web based hydrological warning system at the

  9. Scheduling and Mapping in an Incremental Design Methodology for Distributed Real-Time Embedded Systems

    DEFF Research Database (Denmark)

    Pop, Paul; Eles, Petru; Peng, Zebo

    2004-01-01

    In this paper we present an approach to mapping and scheduling of distributed embedded systems for hard real-time applications, aiming at a minimization of the system modification cost. We consider an incremental design process that starts from an already existing system running a set of applicat......In this paper we present an approach to mapping and scheduling of distributed embedded systems for hard real-time applications, aiming at a minimization of the system modification cost. We consider an incremental design process that starts from an already existing system running a set...... be added to the resulted system. Thus, we propose a heuristic which finds the set of already running applications which have to be remapped and rescheduled at the same time with mapping and scheduling the new application, such that the disturbance on the running system (expressed as the total cost implied...... by the modifications) is minimized. Once this set of applications has been determined, we outline a mapping and scheduling algorithm aimed at fulfilling the requirements stated above. The approaches have been evaluated based on extensive experiments using a large number of generated benchmarks as well as a real...

  10. Distributed Resource Energy Analysis and Management System (DREAMS) Development for Real-time Grid Operations

    Energy Technology Data Exchange (ETDEWEB)

    Nakafuji, Dora [Hawaiian Electric Company, Honululu, HI (United States); Gouveia, Lauren [Hawaiian Electric Company, Honululu, HI (United States)

    2016-10-24

    This project supports development of the next generation, integrated energy management infrastructure (EMS) able to incorporate advance visualization of behind-the-meter distributed resource information and probabilistic renewable energy generation forecasts to inform real-time operational decisions. The project involves end-users and active feedback from an Utility Advisory Team (UAT) to help inform how information can be used to enhance operational functions (e.g. unit commitment, load forecasting, Automatic Generation Control (AGC) reserve monitoring, ramp alerts) within two major EMS platforms. Objectives include: Engaging utility operations personnel to develop user input on displays, set expectations, test and review; Developing ease of use and timeliness metrics for measuring enhancements; Developing prototype integrated capabilities within two operational EMS environments; Demonstrating an integrated decision analysis platform with real-time wind and solar forecasting information and timely distributed resource information; Seamlessly integrating new 4-dimensional information into operations without increasing workload and complexities; Developing sufficient analytics to inform and confidently transform and adopt new operating practices and procedures; Disseminating project lessons learned through industry sponsored workshops and conferences;Building on collaborative utility-vendor partnership and industry capabilities

  11. Real time hardware implementation of power converters for grid integration of distributed generation and STATCOM systems

    Science.gov (United States)

    Jaithwa, Ishan

    Deployment of smart grid technologies is accelerating. Smart grid enables bidirectional flows of energy and energy-related communications. The future electricity grid will look very different from today's power system. Large variable renewable energy sources will provide a greater portion of electricity, small DERs and energy storage systems will become more common, and utilities will operate many different kinds of energy efficiency. All of these changes will add complexity to the grid and require operators to be able to respond to fast dynamic changes to maintain system stability and security. This thesis investigates advanced control technology for grid integration of renewable energy sources and STATCOM systems by verifying them on real time hardware experiments using two different systems: d SPACE and OPAL RT. Three controls: conventional, direct vector control and the intelligent Neural network control were first simulated using Matlab to check the stability and safety of the system and were then implemented on real time hardware using the d SPACE and OPAL RT systems. The thesis then shows how dynamic-programming (DP) methods employed to train the neural networks are better than any other controllers where, an optimal control strategy is developed to ensure effective power delivery and to improve system stability. Through real time hardware implementation it is proved that the neural vector control approach produces the fastest response time, low overshoot, and, the best performance compared to the conventional standard vector control method and DCC vector control technique. Finally the entrepreneurial approach taken to drive the technologies from the lab to market via ORANGE ELECTRIC is discussed in brief.

  12. Chiral Magnetic Effect and Anomalous Transport from Real-Time Lattice Simulations

    International Nuclear Information System (INIS)

    Müller, Niklas; Schlichting, Sören; Sharma, Sayantan

    2016-01-01

    Here, we present a first-principles study of anomaly induced transport phenomena by performing real-time lattice simulations with dynamical fermions coupled simultaneously to non-Abelian S U (N _c) and Abelian U (1) gauge fields. By investigating the behavior of vector and axial currents during a sphaleron transition in the presence of an external magnetic field, we demonstrate how the interplay of the chiral magnetic and chiral separation effect leads to the formation of a propagating wave. Furthermore, we analyze the dependence of the magnitude of the induced vector current and the propagation of the wave on the amount of explicit chiral symmetry breaking due to finite quark masses.

  13. Development of simulator for the uranium enrichment plant using a real-time expert system

    International Nuclear Information System (INIS)

    Kodama, Shinichi; Kondo, Kazuhiro.

    1996-01-01

    The uranium enrichment plant simulator of the new material centrifuge cascade for intelligent process monitoring and alarm generation has been developed by applying an artificial intelligence technology. The real time expert shell, G2 has been used for the system development. The UF6 supply system and cascade equipment was modeled using G2. For a detailed calculation of the cascade, the cascade static characteristic FORTRAN program has been used. These calculation results have been used for the diagnosis of a suspicious behavior in measurement data. Especially, when the deviation of the product uranium concentration was detected, the cause of the deviation was inferred from the knowledge base. (author)

  14. Faster-than-real-time robot simulation for plan development and robot safety

    International Nuclear Information System (INIS)

    Crane, C.D. III; Dalton, R.; Ogles, J.; Tulenko, J.S.; Zhou, X.

    1990-01-01

    The University of Florida, in cooperation with the Universities of Texas, Tennessee, and Michigan and Oak Ridge National Laboratory (ORNL), is developing an advanced robotic system for the US Department of Energy under the University Program for Robotics for Advanced Reactors. As part of this program, the University of Florida has been pursuing the development of a faster-than-real-time robotic simulation program for planning and control of mobile robotic operations to ensure the efficient and safe operation of mobile robots in nuclear power plants and other hazardous environments

  15. Design and implementation of a software tool intended for simulation and test of real time codes

    International Nuclear Information System (INIS)

    Le Louarn, C.

    1986-09-01

    The objective of real time software testing is to show off processing errors and unobserved functional requirements or timing constraints in a code. In the perspective of safety analysis of nuclear equipments of power plants testing should be carried independently from the physical process (which is not generally available), and because casual hardware failures must be considered. We propose here a simulation and test tool, integrally software, with large interactive possibilities for testing assembly code running on microprocessor. The OST (outil d'aide a la simulation et au Test de logiciels temps reel) simulates code execution and hardware or software environment behaviour. Test execution is closely monitored and many useful informations are automatically saved. The present thesis work details, after exposing methods and tools dedicated to real time software, the OST system. We show the internal mechanisms and objects of the system: particularly ''events'' (which describe evolutions of the system under test) and mnemonics (which describe the variables). Then, we detail the interactive means available to the user for constructing the test data and the environment of the tested software. Finally, a prototype implementation is presented along with the results of the tests carried out. This demonstrates the many advantages of the use of an automatic tool over a manual investigation. As a conclusion, further developments, nececessary to complete the final tool are rewieved [fr

  16. Analysis of actuator delay and its effect on uncertainty quantification for real-time hybrid simulation

    Science.gov (United States)

    Chen, Cheng; Xu, Weijie; Guo, Tong; Chen, Kai

    2017-10-01

    Uncertainties in structure properties can result in different responses in hybrid simulations. Quantification of the effect of these uncertainties would enable researchers to estimate the variances of structural responses observed from experiments. This poses challenges for real-time hybrid simulation (RTHS) due to the existence of actuator delay. Polynomial chaos expansion (PCE) projects the model outputs on a basis of orthogonal stochastic polynomials to account for influences of model uncertainties. In this paper, PCE is utilized to evaluate effect of actuator delay on the maximum displacement from real-time hybrid simulation of a single degree of freedom (SDOF) structure when accounting for uncertainties in structural properties. The PCE is first applied for RTHS without delay to determine the order of PCE, the number of sample points as well as the method for coefficients calculation. The PCE is then applied to RTHS with actuator delay. The mean, variance and Sobol indices are compared and discussed to evaluate the effects of actuator delay on uncertainty quantification for RTHS. Results show that the mean and the variance of the maximum displacement increase linearly and exponentially with respect to actuator delay, respectively. Sensitivity analysis through Sobol indices also indicates the influence of the single random variable decreases while the coupling effect increases with the increase of actuator delay.

  17. Real-time Data Access Monitoring in Distributed, Multi-petabyte Systems

    Energy Technology Data Exchange (ETDEWEB)

    Azemoon, Tofigh; Becla, Jacek, a=Hanushevsky, Andrew; Turri, Massimiliano; /SLAC

    2008-04-22

    Petascale systems are in existence today and will become common in the next few years. Such systems are inevitably very complex, highly distributed and heterogeneous. Monitoring a petascale system in real-time and understanding its status at any given moment without impacting its performance is a highly intricate task. Common approaches and off-the-shelf tools are either unusable, do not scale, or severely impact the performance of the monitored servers. This paper describes unobtrusive monitoring software developed at Stanford Linear Accelerator Center (SLAC) for a highly distributed petascale production data set. The paper describes the employed solutions, the lessons learned, the problems still to be addressed, and explains how the system can be reused elsewhere.

  18. Design optimization for security-and safety-critical distributed real-time applications

    DEFF Research Database (Denmark)

    Jiang, Wei; Pop, Paul; Jiang, Ke

    2016-01-01

    requirements on confidentiality of messages, task replication is used to enhance system reliability, and dynamic voltage and frequency scaling is used for energy efficiency of tasks. It is challenging to address these factors simultaneously, e.g., better security protections need more computing resources......In this paper, we are interested in the design of real-time applications with security, safety, timing, and energy requirements. The applications are scheduled with cyclic scheduling, and are mapped on distributed heterogeneous architectures. Cryptographic services are deployed to satisfy security...... and consume more energy, while lower voltages and frequencies may impair schedulability and security, and also lead to reliability degradation. We introduce a vulnerability based method to quantify the security performance of communications on distributed systems. We then focus on determining the appropriate...

  19. SAFCM: A Security-Aware Feedback Control Mechanism for Distributed Real-Time Embedded Systems

    DEFF Research Database (Denmark)

    Ma, Yue; Jiang, Wei; Sang, Nan

    2012-01-01

    Distributed Real-time Embedded (DRE) systems are facing great challenges in networked, unpredictable and especially unsecured environments. In such systems, there is a strong need to enforce security on distributed computing nodes in order to guard against potential threats, while satisfying......-time systems, a multi-input multi-output feedback loop is designed and a model predictive controller is deployed based on an equation model that describes the dynamic behavior of the DRE systems. This control loop uses security level scaling to globally control the CPU utilization and security performance...... for the whole system. We propose a "security level" metric based on an evolution of cryptography algorithms used in embedded systems. Experimental results demonstrate that SAFCM not only has the excellent adaptivity compared to open-loop mechanism, but also has a better overall performance than PID control...

  20. Research on real-time simulation test for upgrades of digital I and C system in nuclear power plant

    International Nuclear Information System (INIS)

    Shi Ji; Jiang Mingyu; Ma Yunqin

    2005-01-01

    The developing trend that digital instrument and control (I and C) system will supplant traditional analog I and C system in nuclear power plant is emphasized. This paper introduces mathematical model of steam generator of full scope simulator for nuclear power plant. The independent real-time simulation system, which forms the interactive closed loop together with the steam generator control system, can be applied to provide a simulation target for upgrades of instrument and control system and the research of control schemes. At the same time, a simulation method for this purpose is presented in this paper. In this method all of the hardware and software are composed of real distributed control system except the model of controlled object. This will not only create favorable conditions for commissioning on site in the future, but also give a theoretical analysis for upgrades of digital I and C system in nuclear power plant. (authors)

  1. Discrete events simulation of a route with traffic lights through automated control in real time

    Directory of Open Access Journals (Sweden)

    Rodrigo César Teixeira Baptista

    2013-03-01

    Full Text Available This paper presents the integration and communication in real-time of a discrete event simulation model with an automatic control system. The simulation model of an intersection with roads having traffic lights was built in the Arena environment. The integration and communication have been made via network, and the control system was operated by a programmable logic controller. Scenarios were simulated for the free, regular and congested traffic situations. The results showed the average number of vehicles that entered in the system and that were retained and also the total average time of the crossing of the vehicles on the road. In general, the model allowed evaluating the behavior of the traffic in each of the ways and the commands from the controller to activation and deactivation of the traffic lights.

  2. Model-based framework for multi-axial real-time hybrid simulation testing

    Science.gov (United States)

    Fermandois, Gaston A.; Spencer, Billie F.

    2017-10-01

    Real-time hybrid simulation is an efficient and cost-effective dynamic testing technique for performance evaluation of structural systems subjected to earthquake loading with rate-dependent behavior. A loading assembly with multiple actuators is required to impose realistic boundary conditions on physical specimens. However, such a testing system is expected to exhibit significant dynamic coupling of the actuators and suffer from time lags that are associated with the dynamics of the servo-hydraulic system, as well as control-structure interaction (CSI). One approach to reducing experimental errors considers a multi-input, multi-output (MIMO) controller design, yielding accurate reference tracking and noise rejection. In this paper, a framework for multi-axial real-time hybrid simulation (maRTHS) testing is presented. The methodology employs a real-time feedback-feedforward controller for multiple actuators commanded in Cartesian coordinates. Kinematic transformations between actuator space and Cartesian space are derived for all six-degrees-offreedom of the moving platform. Then, a frequency domain identification technique is used to develop an accurate MIMO transfer function of the system. Further, a Cartesian-domain model-based feedforward-feedback controller is implemented for time lag compensation and to increase the robustness of the reference tracking for given model uncertainty. The framework is implemented using the 1/5th-scale Load and Boundary Condition Box (LBCB) located at the University of Illinois at Urbana- Champaign. To demonstrate the efficacy of the proposed methodology, a single-story frame subjected to earthquake loading is tested. One of the columns in the frame is represented physically in the laboratory as a cantilevered steel column. For realtime execution, the numerical substructure, kinematic transformations, and controllers are implemented on a digital signal processor. Results show excellent performance of the maRTHS framework when six

  3. A Formal Approach to Run-Time Evaluation of Real-Time Behaviour in Distributed Process Control Systems

    DEFF Research Database (Denmark)

    Kristensen, C.H.

    This thesis advocates a formal approach to run-time evaluation of real-time behaviour in distributed process sontrol systems, motivated by a growing interest in applying the increasingly popular formal methods in the application area of distributed process control systems. We propose to evaluate...... because the real-time aspects of distributed process control systems are considered to be among the hardest and most interesting to handle....

  4. Virtual reality cerebral aneurysm clipping simulation with real-time haptic feedback.

    Science.gov (United States)

    Alaraj, Ali; Luciano, Cristian J; Bailey, Daniel P; Elsenousi, Abdussalam; Roitberg, Ben Z; Bernardo, Antonio; Banerjee, P Pat; Charbel, Fady T

    2015-03-01

    With the decrease in the number of cerebral aneurysms treated surgically and the increase of complexity of those treated surgically, there is a need for simulation-based tools to teach future neurosurgeons the operative techniques of aneurysm clipping. To develop and evaluate the usefulness of a new haptic-based virtual reality simulator in the training of neurosurgical residents. A real-time sensory haptic feedback virtual reality aneurysm clipping simulator was developed using the ImmersiveTouch platform. A prototype middle cerebral artery aneurysm simulation was created from a computed tomographic angiogram. Aneurysm and vessel volume deformation and haptic feedback are provided in a 3-dimensional immersive virtual reality environment. Intraoperative aneurysm rupture was also simulated. Seventeen neurosurgery residents from 3 residency programs tested the simulator and provided feedback on its usefulness and resemblance to real aneurysm clipping surgery. Residents thought that the simulation would be useful in preparing for real-life surgery. About two-thirds of the residents thought that the 3-dimensional immersive anatomic details provided a close resemblance to real operative anatomy and accurate guidance for deciding surgical approaches. They thought the simulation was useful for preoperative surgical rehearsal and neurosurgical training. A third of the residents thought that the technology in its current form provided realistic haptic feedback for aneurysm surgery. Neurosurgical residents thought that the novel immersive VR simulator is helpful in their training, especially because they do not get a chance to perform aneurysm clippings until late in their residency programs.

  5. Real-time Monitoring and Simulating of Urban Flood, a Case Study in Guangzhou

    Science.gov (United States)

    Huang, H.; Wang, X.; Zhang, S.; Liu, Y.

    2014-12-01

    In recent years urban flood frequently occurred and seriously impacted city's normal operation, particular on transportation. The increase of urban flood could be attributed to many factors, such as the increase of impervious land surface and extreme precipitation, the decrease of surface storage capacity, poor maintenance of drainage utilities, and so on. In order to provide accurate and leading prediction on urban flooding, this study acquires precise urban topographic data via air-borne Lidar system, collects detailed underground drainage pipes, and installs in-situ monitoring networks on precipitation, water level, video record and traffic speed in the downtown area of Panyu District, Guangzhou, China. Based on the above data acquired, a urban flood model with EPA SWMM5 is established to simulate the flooding and inundation processes in the study area of 20 km2. The model is driven by the real-time precipitation data and calibrated by the water level data, which are converted to flooding volume with precise topographic data. After calibration, the model could be employed to conduct sensitivity analysis for investigating primary factors of urban flooding, and to simulate the flooding processes in different scenarios, which are beneficial to assessment of flooding risk and drainage capacity. This model is expected to provide real-time forecasting in emergency management.

  6. Feasibility of the integration of CRONOS, a 3-D neutronics code, into real-time simulators

    International Nuclear Information System (INIS)

    Ragusa, J.C.

    2001-01-01

    In its effort to contribute to nuclear power plant safety, CEA proposes the integration of an engineering grade 3-D neutronics code into a real-time plant analyser. This paper describes the capabilities of the neutronics code CRONOS to achieve a fast running performance. First, we will present current core models in simulators and explain their drawbacks. Secondly, the mean features of CRONOS's spatial-kinetics methods will be reviewed. We will then present an optimum core representation with respect to mesh size, choice of finite elements (FE) basis and execution time, for accurate results as well as the multi 1-D thermal-hydraulics (T/H) model developed to take into account 3-D effects in updating the cross-sections. A Main Steam Line Break (MSLB) End-of-Life (EOL) Hot-Zero-Power (HZP) accident will be used as an example, before we conclude with the perspectives of integrating CRONOS's 3-D core model into real-time simulators. (author)

  7. Feasibility of the integration of CRONOS, a 3-D neutronics code, into real-time simulators

    Energy Technology Data Exchange (ETDEWEB)

    Ragusa, J.C. [CEA Saclay, Dept. de Mecanique et de Technologie, 91 - Gif-sur-Yvette (France)

    2001-07-01

    In its effort to contribute to nuclear power plant safety, CEA proposes the integration of an engineering grade 3-D neutronics code into a real-time plant analyser. This paper describes the capabilities of the neutronics code CRONOS to achieve a fast running performance. First, we will present current core models in simulators and explain their drawbacks. Secondly, the mean features of CRONOS's spatial-kinetics methods will be reviewed. We will then present an optimum core representation with respect to mesh size, choice of finite elements (FE) basis and execution time, for accurate results as well as the multi 1-D thermal-hydraulics (T/H) model developed to take into account 3-D effects in updating the cross-sections. A Main Steam Line Break (MSLB) End-of-Life (EOL) Hot-Zero-Power (HZP) accident will be used as an example, before we conclude with the perspectives of integrating CRONOS's 3-D core model into real-time simulators. (author)

  8. Fault tolerant distributed real time computer systems for I and C of prototype fast breeder reactor

    Energy Technology Data Exchange (ETDEWEB)

    Manimaran, M., E-mail: maran@igcar.gov.in; Shanmugam, A.; Parimalam, P.; Murali, N.; Satya Murty, S.A.V.

    2014-03-15

    Highlights: • Architecture of distributed real time computer system (DRTCS) used in I and C of PFBR is explained. • Fault tolerant (hot standby) architecture, fault detection and switch over are detailed. • Scaled down model was used to study functional and performance requirements of DRTCS. • Quality of service parameters for scaled down model was critically studied. - Abstract: Prototype fast breeder reactor (PFBR) is in the advanced stage of construction at Kalpakkam, India. Three-tier architecture is adopted for instrumentation and control (I and C) of PFBR wherein bottom tier consists of real time computer (RTC) systems, middle tier consists of process computers and top tier constitutes of display stations. These RTC systems are geographically distributed and networked together with process computers and display stations. Hot standby architecture comprising of dual redundant RTC systems with switch over logic system is deployed in order to achieve fault tolerance. Fault tolerant dual redundant network connectivity is provided in each RTC system and TCP/IP protocol is selected for network communication. In order to assess the performance of distributed RTC systems, scaled down model was developed with 9 representative systems and nearly 15% of I and C signals of PFBR were connected and monitored. Functional and performance testing were carried out for each RTC system and the fault tolerant characteristics were studied by creating various faults into the system and observed the performance. Various quality of service parameters like connection establishment delay, priority parameter, transit delay, throughput, residual error ratio, etc., are critically studied for the network.

  9. Real-time simulation: first-hand experience of the challenges of community nursing for students.

    Science.gov (United States)

    Reynolds, Stephanie; Cooper-Stanton, Garry; Potter, Andrew

    2018-04-02

    The Community Challenge is a simulated community event for pre-registration nursing students across all four fields. Through the provision of real-time simulation, the Community Challenge has combined a deeper learning for both nursing students and the drama students who were involved in making the scenarios real and interactive. The event was run over 5 days, with positive evaluations from students and staff. Furthermore, Community Challenge has been found to be successful in expanding opportunities for students that align with national drivers, curriculum planning and interprofessional learning. The event has allowed students to engage in learning with other fields, enhancing their own practice. The Community Challenge has been found to enhance the link between theory and practice within primary care, promoting the relevance and importance of community care within nursing.

  10. Digital video timing analyzer for the evaluation of PC-based real-time simulation systems

    Science.gov (United States)

    Jones, Shawn R.; Crosby, Jay L.; Terry, John E., Jr.

    2009-05-01

    Due to the rapid acceleration in technology and the drop in costs, the use of commercial off-the-shelf (COTS) PC-based hardware and software components for digital and hardware-in-the-loop (HWIL) simulations has increased. However, the increase in PC-based components creates new challenges for HWIL test facilities such as cost-effective hardware and software selection, system configuration and integration, performance testing, and simulation verification/validation. This paper will discuss how the Digital Video Timing Analyzer (DiViTA) installed in the Aviation and Missile Research, Development and Engineering Center (AMRDEC) provides quantitative characterization data for PC-based real-time scene generation systems. An overview of the DiViTA is provided followed by details on measurement techniques, applications, and real-world examples of system benefits.

  11. Automatic Optimization for Large-Scale Real-Time Coastal Water Simulation

    Directory of Open Access Journals (Sweden)

    Shunli Wang

    2016-01-01

    Full Text Available We introduce an automatic optimization approach for the simulation of large-scale coastal water. To solve the singular problem of water waves obtained with the traditional model, a hybrid deep-shallow-water model is estimated by using an automatic coupling algorithm. It can handle arbitrary water depth and different underwater terrain. As a certain feature of coastal terrain, coastline is detected with the collision detection technology. Then, unnecessary water grid cells are simplified by the automatic simplification algorithm according to the depth. Finally, the model is calculated on Central Processing Unit (CPU and the simulation is implemented on Graphics Processing Unit (GPU. We show the effectiveness of our method with various results which achieve real-time rendering on consumer-level computer.

  12. Simulation study of near-real-time accounting in a generic reprocessing plant

    International Nuclear Information System (INIS)

    Coulter, C.A.; Whiteson, R.; Zardecki, A.

    1992-01-01

    Our simulation program FacSim has been used to estimate balance closure variances for a number of real proposed nuclear material processing facilities that rely primarily on item measurements. We are enhancing the program so that it can be applied to facilities such as reprocessing plants that handle bulk materials ad primarily perform bulk and flow measurements. The extended simulation program can apply any of several types of sequential statistical tests to near-real-time accounting information to evaluate the capability of the facility accounting system to detect material and operational anomalies in a timely fashion. The program allows facility designers and operators to evaluate measurement and anomaly detection strategies before system implementation and to demonstrate facility's capability for maintaining accurate inventory information during plant operation. These features are illustrated by application to a generic reprocessing plant

  13. Power system analysis of Hanlim superconducting HVDC system using real time digital simulator

    Science.gov (United States)

    Won, Y. J.; Kim, J. G.; Kim, A. R.; Kim, G. H.; Park, M.; Yu, I. K.; Sim, K. D.; Cho, J.; Lee, S.; Jeong, K. W.; Watanabe, K.

    2011-11-01

    Jeju island is located approximately 100 km south from the mainland of Korea, and had a peak load of about 553 MW in 2008. The demand increases 7.2% a year over the last 5 years. Since the wind profiles of Jeju island are more favorable than mainland of Korea, many companies have shown interest in the wind power business at the Jeju island. Moreover KEPCO has a plan for renewable energy test too whose power will be delivered by HVDC system. One kilometer length of total 8 km was designed as superconducting DC cable. Rest 7 km will be the conventional overhead line. In this paper, the authors have developed a simulation model of the power network around 8 km HVDC system using real time digital simulator (RTDS).

  14. Distributed Arithmetic for Efficient Base-Band Processing in Real-Time GNSS Software Receivers

    Directory of Open Access Journals (Sweden)

    Grégoire Waelchli

    2010-01-01

    Full Text Available The growing market of GNSS capable mobile devices is driving the interest of GNSS software solutions, as they can share many system resources (processor, memory, reducing both the size and the cost of their integration. Indeed, with the increasing performance of modern processors, it becomes now feasible to implement in software a multichannel GNSS receiver operating in real time. However, a major issue with this approach is the large computing resources required for the base-band processing, in particular for the correlation operations. Therefore, new algorithms need to be developed in order to reduce the overall complexity of the receiver architecture. Towards that aim, this paper first introduces the challenges of the software implementation of a GPS receiver, with a main focus given to the base-band processing and correlation operations. It then describes the already existing solutions and, from this, introduces a new algorithm based on distributed arithmetic.

  15. Infrared Tomography: Data Distribution System for Real-time Mass Flow Rate Measurement

    Directory of Open Access Journals (Sweden)

    Ruzairi Abdul Rahim

    2007-06-01

    Full Text Available The system developed in this research has the objective of measuring mass flow rate in an online mode. If a single computer is used as data processing unit, a longer time is needed to produce a measurement result. In the research carried out by previous researcher shows about 11.2 seconds is needed to obtain one mass flow rate result in the offline mode (using offline data. This insufficient real-time result will cause problems in a feedback control process when applying the system on industrial plants. To increase the refreshing rate of the measurement result, an investigation on a data distribution system is performed to replace the existing data processing unit.

  16. Timing Analysis of Mixed-Criticality Hard Real-Time Applications Implemented on Distributed Partitioned Architectures

    DEFF Research Database (Denmark)

    Marinescu, Sorin Ovidiu; Tamas-Selicean, Domitian; Acretoaie, Vlad

    In this paper we are interested in the timing analysis of mixed-criticality embedded real-time applications mapped on distributed heterogeneous architectures. Mixedcriticality tasks can be integrated onto the same architecture only if there is enough spatial and temporal separation among them. We...... in partitions using fixedpriority preemptive scheduling. We have extended the stateof- the-art algorithms for schedulability analysis to take into account the partitions. The proposed algorithm has been evaluated using several synthetic and real-life benchmarks....... consider that the separation is provided by partitioning, such that applications run in separate partitions, and each partition is allocated several time slots on a processor. Each partition can have its own scheduling policy. We are interested to determine the worst-case response times of tasks scheduled...

  17. Robust and flexible mapping for real-time distributed applications during the early design phases

    DEFF Research Database (Denmark)

    Gan, Junhe; Pop, Paul; Gruian, Flavius

    2012-01-01

    has a high chance of being schedulable, considering the wcet uncertainties, whereas a flexible mapping has a high chance to successfully accommodate the future scenarios. We propose a Genetic Algorithm-based approach to solve this optimization problem. Extensive experiments show the importance......We are interested in mapping hard real-time applications on distributed heterogeneous architectures. An application is modeled as a set of tasks, and we consider a fixed-priority preemptive scheduling policy. We target the early design phases, when decisions have a high impact on the subsequent...... in the functionality requirements are captured using “future scenarios”, which are task sets that model functionality likely to be added in the future. In this context, we derive a mapping of tasks in the application, such that the resulted implementation is both robust and flexible. Robust means that the application...

  18. Modern Energy Markets Real-Time Pricing, Renewable Resources and Efficient Distribution

    CERN Document Server

    Kopsakangas-Savolainen, Maria

    2012-01-01

    Energy has moved to the forefront in terms of societal and economic development. Modern Energy Markets is a comprehensive, economically oriented, exploration of modern electricity networks from production and distribution to deregulation and liberalization processes. Updating previous work by the authors, different aspects are considered resulting in a complete and detailed picture of  the systems and characteristics of modern electricity markets. Modern Energy Markets provides clear detail whilst encompassing a broad scope of topics and includes: •A method to model energy production systems including the main characteristics of future demand side management, •Different applications of this model in nuclear and renewable energy scenarios, •An analysis of Real-Time Pricing of electricity and its potential effects across the market, and, •A discussion of the need for regulation in an easily monopolized industry. Engineering and Economics students alike will find that Modern Energy Markets is a succinct...

  19. Real-time generation of the Wigner distribution of complex functions using phase conjugation in photorefractive materials.

    Science.gov (United States)

    Sun, P C; Fainman, Y

    1990-09-01

    An optical processor for real-time generation of the Wigner distribution of complex amplitude functions is introduced. The phase conjugation of the input signal is accomplished by a highly efficient self-pumped phase conjugator based on a 45 degrees -cut barium titanate photorefractive crystal. Experimental results on the real-time generation of Wigner distribution slices for complex amplitude two-dimensional optical functions are presented and discussed.

  20. FPGA-based real-time simulation of power converters of renewable energy sources

    Energy Technology Data Exchange (ETDEWEB)

    Kokenyesi, Tamas; Varjasi, Istvan [Budapest University of Technology and Economics, Department of Automation and Applied Informatics (Hungary)], e-mail: kokenyesi.tamas@gmail.com, email: varjasi@aut.bme.hu

    2011-07-01

    This paper presents a hardware-in-the-loop testing (HIL) approach based on a field programmable gate array (FPGA) real-time simulation with real measured signals designed to reduce the cost and time for testing the main circuit of a power converter significantly. This method allows the control unit to measure its outputs on the same signal level in a completely transparent way, unlike other computer based simulation methods. As an example, a simulator for a three-phase inverter used for DC/AC conversion or frequency control is described and the simulated network illustrated. The calculation procedure and relative equations are also detailed, with simulation parameters and some measurement results being presented. It was found that the main advantage of this method is speed, which was only limited by the actual capabilities of the FPGA used. This method can be applied to a wide variety of analog circuits, reducing time to market. More complex circuits and higher frequencies could be simulated in the future with the evolution of FPGAs.

  1. Simulations of relativistic quantum plasmas using real-time lattice scalar QED

    Science.gov (United States)

    Shi, Yuan; Xiao, Jianyuan; Qin, Hong; Fisch, Nathaniel J.

    2018-05-01

    Real-time lattice quantum electrodynamics (QED) provides a unique tool for simulating plasmas in the strong-field regime, where collective plasma scales are not well separated from relativistic-quantum scales. As a toy model, we study scalar QED, which describes self-consistent interactions between charged bosons and electromagnetic fields. To solve this model on a computer, we first discretize the scalar-QED action on a lattice, in a way that respects geometric structures of exterior calculus and U(1)-gauge symmetry. The lattice scalar QED can then be solved, in the classical-statistics regime, by advancing an ensemble of statistically equivalent initial conditions in time, using classical field equations obtained by extremizing the discrete action. To demonstrate the capability of our numerical scheme, we apply it to two example problems. The first example is the propagation of linear waves, where we recover analytic wave dispersion relations using numerical spectrum. The second example is an intense laser interacting with a one-dimensional plasma slab, where we demonstrate natural transition from wakefield acceleration to pair production when the wave amplitude exceeds the Schwinger threshold. Our real-time lattice scheme is fully explicit and respects local conservation laws, making it reliable for long-time dynamics. The algorithm is readily parallelized using domain decomposition, and the ensemble may be computed using quantum parallelism in the future.

  2. Real-time tumor ablation simulation based on the dynamic mode decomposition method

    KAUST Repository

    Bourantas, George C.

    2014-05-01

    Purpose: The dynamic mode decomposition (DMD) method is used to provide a reliable forecasting of tumor ablation treatment simulation in real time, which is quite needed in medical practice. To achieve this, an extended Pennes bioheat model must be employed, taking into account both the water evaporation phenomenon and the tissue damage during tumor ablation. Methods: A meshless point collocation solver is used for the numerical solution of the governing equations. The results obtained are used by the DMD method for forecasting the numerical solution faster than the meshless solver. The procedure is first validated against analytical and numerical predictions for simple problems. The DMD method is then applied to three-dimensional simulations that involve modeling of tumor ablation and account for metabolic heat generation, blood perfusion, and heat ablation using realistic values for the various parameters. Results: The present method offers very fast numerical solution to bioheat transfer, which is of clinical significance in medical practice. It also sidesteps the mathematical treatment of boundaries between tumor and healthy tissue, which is usually a tedious procedure with some inevitable degree of approximation. The DMD method provides excellent predictions of the temperature profile in tumors and in the healthy parts of the tissue, for linear and nonlinear thermal properties of the tissue. Conclusions: The low computational cost renders the use of DMD suitable forin situ real time tumor ablation simulations without sacrificing accuracy. In such a way, the tumor ablation treatment planning is feasible using just a personal computer thanks to the simplicity of the numerical procedure used. The geometrical data can be provided directly by medical image modalities used in everyday practice. © 2014 American Association of Physicists in Medicine.

  3. System-level power optimization for real-time distributed embedded systems

    Science.gov (United States)

    Luo, Jiong

    Power optimization is one of the crucial design considerations for modern electronic systems. In this thesis, we present several system-level power optimization techniques for real-time distributed embedded systems, based on dynamic voltage scaling, dynamic power management, and management of peak power and variance of the power profile. Dynamic voltage scaling has been widely acknowledged as an important and powerful technique to trade off dynamic power consumption and delay. Efficient dynamic voltage scaling requires effective variable-voltage scheduling mechanisms that can adjust voltages and clock frequencies adaptively based on workloads and timing constraints. For this purpose, we propose static variable-voltage scheduling algorithms utilizing criticalpath driven timing analysis for the case when tasks are assumed to have uniform switching activities, as well as energy-gradient driven slack allocation for a more general scenario. The proposed techniques can achieve closeto-optimal power savings with very low computational complexity, without violating any real-time constraints. We also present algorithms for power-efficient joint scheduling of multi-rate periodic task graphs along with soft aperiodic tasks. The power issue is addressed through both dynamic voltage scaling and power management. Periodic task graphs are scheduled statically. Flexibility is introduced into the static schedule to allow the on-line scheduler to make local changes to PE schedules through resource reclaiming and slack stealing, without interfering with the validity of the global schedule. We provide a unified framework in which the response times of aperiodic tasks and power consumption are dynamically optimized simultaneously. Interconnection network fabrics point to a new generation of power-efficient and scalable interconnection architectures for distributed embedded systems. As the system bandwidth continues to increase, interconnection networks become power/energy limited as

  4. Real-time tumor tracking using implanted positron emission markers: Concept and simulation study

    International Nuclear Information System (INIS)

    Xu Tong; Wong, Jerry T.; Shikhaliev, Polad M.; Ducote, Justin L.; Al-Ghazi, Muthana S.; Molloi, Sabee

    2006-01-01

    The delivery accuracy of radiation therapy for pulmonary and abdominal tumors suffers from tumor motion due to respiration. Respiratory gating should be applied to avoid the use of a large target volume margin that results in a substantial dose to the surrounding normal tissue. Precise respiratory gating requires the exact spatial position of the tumor to be determined in real time during treatment. Usually, fiducial markers are implanted inside or next to the tumor to provide both accurate patient setup and real-time tumor tracking. However, current tumor tracking systems require either substantial x-ray exposure to the patient or large fiducial markers that limit the value of their application for pulmonary tumors. We propose a real-time tumor tracking system using implanted positron emission markers (PeTrack). Each marker will be labeled with low activity positron emitting isotopes, such as 124 I, 74 As, or 84 Rb. These isotopes have half-lives comparable to the duration of radiation therapy (from a few days to a few weeks). The size of the proposed PeTrack marker will be 0.5-0.8 mm, which is approximately one-half the size of markers currently employed in other techniques. By detecting annihilation gammas using position-sensitive detectors, multiple positron emission markers can be tracked in real time. A multimarker localization algorithm was developed using an Expectation-Maximization clustering technique. A Monte Carlo simulation model was developed for the PeTrack system. Patient dose, detector sensitivity, and scatter fraction were evaluated. Depending on the isotope, the lifetime dose from a 3.7 MBq PeTrack marker was determined to be 0.7-5.0 Gy at 10 mm from the marker. At the center of the field of view (FOV), the sensitivity of the PeTrack system was 240-320 counts/s per 1 MBq marker activity within a 30 cm thick patient. The sensitivity was reduced by 45% when the marker was near the edge of the FOV. The scatter fraction ranged from 12% ( 124 I, 74 As

  5. The use of best estimate codes to improve the simulation in real time

    International Nuclear Information System (INIS)

    Rivero, N.; Esteban, J. A.; Lenhardt, G.

    2007-01-01

    Best estimate codes are assumed to be the technology solution providing the most realistic and accurate response. Best estimate technology provides a complementary solution to the conservative simulation technology usually applied to determine plant safety margins and perform security related studies. Tecnatom in the early 90's, within the MAS project, pioneered the initiative to implement best estimate code in its training simulators. Result of this project was the implementation of the first six-equations thermal hydraulic code worldwide (TRAC R T), running in a training environment. To meet real time and other specific training requirements, it was necessary to overcome important difficulties. Tecnatom has just adapted the Global Nuclear Fuel core Design code: PANAC 11, and is about to complete the General Electric TRACG04 thermal hydraulic code adaptation. This technology features a unique solution for nuclear plants aiming at providing the highest fidelity in simulation, enabling to consider the simulator as a multipurpose: engineering and training, simulation platform. Besides, a visual environment designed to optimize the models life cycle, covering both pre and post-processing activities, is in its late development phase. (Author)

  6. Real time monitoring of water distribution in an operando fuel cell during transient states

    Science.gov (United States)

    Martinez, N.; Peng, Z.; Morin, A.; Porcar, L.; Gebel, G.; Lyonnard, S.

    2017-10-01

    The water distribution of an operating proton exchange membrane fuel cell (PEMFC) was monitored in real time by using Small Angle Neutron Scattering (SANS). The formation of liquid water was obtained simultaneously with the evolution of the water content inside the membrane. Measurements were performed when changing current with a time resolution of 10 s, providing insights on the kinetics of water management prior to the stationary phase. We confirmed that water distribution is strongly heterogeneous at the scale at of the whole Membrane Electrode Assembly. As already reported, at the local scale there is no straightforward link between the amounts of water present inside and outside the membrane. However, we show that the temporal evolutions of these two parameters are strongly correlated. In particular, the local membrane water content is nearly instantaneously correlated to the total liquid water content, whether it is located at the anode or cathode side. These results can help in optimizing 3D stationary diphasic models used to predict PEMFC water distribution.

  7. Virtual Reality Cerebral Aneurysm Clipping Simulation With Real-time Haptic Feedback

    Science.gov (United States)

    Alaraj, Ali; Luciano, Cristian J.; Bailey, Daniel P.; Elsenousi, Abdussalam; Roitberg, Ben Z.; Bernardo, Antonio; Banerjee, P. Pat; Charbel, Fady T.

    2014-01-01

    Background With the decrease in the number of cerebral aneurysms treated surgically and the increase of complexity of those treated surgically, there is a need for simulation-based tools to teach future neurosurgeons the operative techniques of aneurysm clipping. Objective To develop and evaluate the usefulness of a new haptic-based virtual reality (VR) simulator in the training of neurosurgical residents. Methods A real-time sensory haptic feedback virtual reality aneurysm clipping simulator was developed using the Immersive Touch platform. A prototype middle cerebral artery aneurysm simulation was created from a computed tomography angiogram. Aneurysm and vessel volume deformation and haptic feedback are provided in a 3-D immersive VR environment. Intraoperative aneurysm rupture was also simulated. Seventeen neurosurgery residents from three residency programs tested the simulator and provided feedback on its usefulness and resemblance to real aneurysm clipping surgery. Results Residents felt that the simulation would be useful in preparing for real-life surgery. About two thirds of the residents felt that the 3-D immersive anatomical details provided a very close resemblance to real operative anatomy and accurate guidance for deciding surgical approaches. They believed the simulation is useful for preoperative surgical rehearsal and neurosurgical training. One third of the residents felt that the technology in its current form provided very realistic haptic feedback for aneurysm surgery. Conclusion Neurosurgical residents felt that the novel immersive VR simulator is helpful in their training especially since they do not get a chance to perform aneurysm clippings until very late in their residency programs. PMID:25599200

  8. Real-time simulation of biological soft tissues: a PGD approach.

    Science.gov (United States)

    Niroomandi, S; González, D; Alfaro, I; Bordeu, F; Leygue, A; Cueto, E; Chinesta, F

    2013-05-01

    We introduce here a novel approach for the numerical simulation of nonlinear, hyperelastic soft tissues at kilohertz feedback rates necessary for haptic rendering. This approach is based upon the use of proper generalized decomposition techniques, a generalization of PODs. Proper generalized decomposition techniques can be considered as a means of a priori model order reduction and provides a physics-based meta-model without the need for prior computer experiments. The suggested strategy is thus composed of an offline phase, in which a general meta-model is computed, and an online evaluation phase in which the results are obtained at real time. Results are provided that show the potential of the proposed technique, together with some benchmark test that shows the accuracy of the method. Copyright © 2013 John Wiley & Sons, Ltd.

  9. Phasor Measurement Unit and Phasor Data Concentrator test with Real Time Digital Simulator

    DEFF Research Database (Denmark)

    Diakos, Konstantinos; Wu, Qiuwei; Nielsen, Arne Hejde

    2014-01-01

    that is able to derive and communicate synchrophasor measurements of different parts of the power network and the development of tests, according to IEEE standards, that evaluate the performance of PMUs and PDCs. The tests are created by using a Real Time Digital Simulation (RTDS) system. The results obtained......The main focus of the electrical engineers nowadays, is to develop a smart grid that is able to monitor, evaluate and control the power system operation. The integration of Intelligent Electronic Devices (IED s) to the power network, is a strong indication of the inclination to lead the power...... network to a more reliable, secure and economic operation. The implementation of these devices though, demands the warranty of a secure operation and high-accuracy performance. This paper describes the procedure of establishing a PMU (Phasor Measurement Unit)–PDC (Phasor Data Concentrator) platform...

  10. Real time simulation of nonlinear generalized predictive control for wind energy conversion system with nonlinear observer.

    Science.gov (United States)

    Ouari, Kamel; Rekioua, Toufik; Ouhrouche, Mohand

    2014-01-01

    In order to make a wind power generation truly cost-effective and reliable, an advanced control techniques must be used. In this paper, we develop a new control strategy, using nonlinear generalized predictive control (NGPC) approach, for DFIG-based wind turbine. The proposed control law is based on two points: NGPC-based torque-current control loop generating the rotor reference voltage and NGPC-based speed control loop that provides the torque reference. In order to enhance the robustness of the controller, a disturbance observer is designed to estimate the aerodynamic torque which is considered as an unknown perturbation. Finally, a real-time simulation is carried out to illustrate the performance of the proposed controller. Copyright © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

  11. Real-time simulation of thermal stresses and creep in plates subjected to transient heat input

    DEFF Research Database (Denmark)

    Hattel, Jesper Henri; Jacobsen, Torben Krogsdal; Hansen, P.N.

    1997-01-01

    -difference approach. It applies a general formulation which takes into account nonconstant material properties (e.g. temperature, material, or time dependency), heat-transfer coefficients, and creep. The temperature calculation applies a one-dimensional numerical model, whereas the stress analysis is semi......This paper presents a novel numerical technique for solving the temperature and stress fields in a plate subjected to arbitrarily varying transient boundary conditions (transient temperature and heat-flux variations) on a surface. The numerical method is based on the control-volume finite......-two-dimensional. Both plane stress and plane strain conditions are considered as extreme cases. It is shown that, by using the developed numerical technique, very fast real-time simulations can be performed. The method has proved its applicability in e.g. high-pressure die-casting, and applications to this industrial...

  12. A Distributed Computing Framework for Real-Time Detection of Stress and of Its Propagation in a Team.

    Science.gov (United States)

    Pandey, Parul; Lee, Eun Kyung; Pompili, Dario

    2016-11-01

    Stress is one of the key factor that impacts the quality of our daily life: From the productivity and efficiency in the production processes to the ability of (civilian and military) individuals in making rational decisions. Also, stress can propagate from one individual to other working in a close proximity or toward a common goal, e.g., in a military operation or workforce. Real-time assessment of the stress of individuals alone is, however, not sufficient, as understanding its source and direction in which it propagates in a group of people is equally-if not more-important. A continuous near real-time in situ personal stress monitoring system to quantify level of stress of individuals and its direction of propagation in a team is envisioned. However, stress monitoring of an individual via his/her mobile device may not always be possible for extended periods of time due to limited battery capacity of these devices. To overcome this challenge a novel distributed mobile computing framework is proposed to organize the resources in the vicinity and form a mobile device cloud that enables offloading of computation tasks in stress detection algorithm from resource constrained devices (low residual battery, limited CPU cycles) to resource rich devices. Our framework also supports computing parallelization and workflows, defining how the data and tasks divided/assigned among the entities of the framework are designed. The direction of propagation and magnitude of influence of stress in a group of individuals are studied by applying real-time, in situ analysis of Granger Causality. Tangible benefits (in terms of energy expenditure and execution time) of the proposed framework in comparison to a centralized framework are presented via thorough simulations and real experiments.

  13. Distributed real time data processing architecture for the TJ-II data acquisition system

    International Nuclear Information System (INIS)

    Ruiz, M.; Barrera, E.; Lopez, S.; Machon, D.; Vega, J.; Sanchez, E.

    2004-01-01

    This article describes the performance of a new model of architecture that has been developed for the TJ-II data acquisition system in order to increase its real time data processing capabilities. The current model consists of several compact PCI extension for instrumentation (PXI) standard chassis, each one with various digitizers. In this architecture, the data processing capability is restricted to the PXI controller's own performance. The controller must share its CPU resources between the data processing and the data acquisition tasks. In the new model, distributed data processing architecture has been developed. The solution adds one or more processing cards to each PXI chassis. This way it is possible to plan how to distribute the data processing of all acquired signals among the processing cards and the available resources of the PXI controller. This model allows scalability of the system. More or less processing cards can be added based on the requirements of the system. The processing algorithms are implemented in LabVIEW (from National Instruments), providing efficiency and time-saving application development when compared with other efficient solutions

  14. Palantiri: a distributed real-time database system for process control

    International Nuclear Information System (INIS)

    Tummers, B.J.; Heubers, W.P.J.

    1992-01-01

    The medium-energy accelerator MEA, located in Amsterdam, is controlled by a heterogeneous computer network. A large real-time database contains the parameters involved in the control of the accelerator and the experiments. This database system was implemented about ten years ago and has since been extended several times. In response to increased needs the database system has been redesigned. The new database environment, as described in this paper, consists out of two new concepts: (1) A Palantir which is a per machine process that stores the locally declared data and forwards all non local requests for data access to the appropriate machine. It acts as a storage device for data and a looking glass upon the world. (2) Golems: working units that define the data within the Palantir, and that have knowledge of the hardware they control. Applications access the data of a Golem by name (which do resemble Unix path names). The palantir that runs on the same machine as the application handles the distribution of access requests. This paper focuses on the Palantir concept as a distributed data storage and event handling device for process control. (author)

  15. Continuous Real-time Measurements of Vertical Distribution of Magnetic Susceptibility In Soils

    Science.gov (United States)

    Petrovsky, E.; Hulka, Z.; Kapicka, A.; Magprox Team

    Measurements of top-soil magnetic susceptibility are used in approximative outlining polluted areas. However, one of the serious limitations of the method is discrimina- tion between top-soil layers enhanced by atmospherically deposited anthropogenic particles from those dominated by natural particles migrating from magnetically-rich basement rocks. For this purpose, measurements of vertical distribution of magnetic susceptibility along soil profiles is one of the most effective ways in estimating the effect of lithogenic contribution. Up to now, in most cases soil cores have to be mea- sured in laboratory. This method is quite time consuming and does not allow flexible decision about the suitability of the measured site for surface magnetic mapping. In our contribution we will present a new device enabling continuous real-time measure- ments of vertical distribution of magnetic susceptibility directly in field, performed in holes after soil coring. The method is fast, yielding smooth curves (6 data points per 1 mm dept), at least as sensitive as laboratory methods available until now, and at- tached notebook enables direct, on-line control of the lithogenic versus anthropogenic contributions.

  16. Real-time Distributed Economic Dispatch forDistributed Generation Based on Multi-Agent System

    DEFF Research Database (Denmark)

    Luo, Kui; Wu, Qiuwei; Nielsen, Arne Hejde

    2015-01-01

    The distributed economic dispatch for distributed generation is formulated as a optimization problem with equality and inequality constraints. An effective distributed approach based on multi-agent system is proposed for solving the economic dispatch problem in this paper. The proposed approach...... consists of two stages. In the first stage, an adjacency average allocation algorithm is proposed to ensure the generation-demand equality. In the second stage, a local replicator dynamics algorithm is applied to achieve nash equilibrium for the power dispatch game. The approach is implemented in a fully...

  17. Validation of a Robust Neural Real-Time Voltage Estimator for Active Distribution Grids on Field Data

    DEFF Research Database (Denmark)

    Pertl, Michael; Douglass, Philip James; Heussen, Kai

    2018-01-01

    network approach for voltage estimation in active distribution grids by means of measured data from two feeders of a real low voltage distribution grid. The approach enables a real-time voltage estimation at locations in the distribution grid, where otherwise only non-real-time measurements are available......The installation of measurements in distribution grids enables the development of data driven methods for the power system. However, these methods have to be validated in order to understand the limitations and capabilities for their use. This paper presents a systematic validation of a neural...

  18. An inexpensive underwater mine countermeasures simulator with real-time 3D after action review

    Directory of Open Access Journals (Sweden)

    Robert Stone

    2016-10-01

    Full Text Available This paper presents the results of a concept capability demonstration pilot study, the aim of which was to investigate how inexpensive gaming software and hardware technologies could be exploited in the development and evaluation of a simulator prototype for training Royal Navy mine clearance divers, specifically focusing on the detection and accurate reporting of the location and condition of underwater ordnance. The simulator was constructed using the Blender open source 3D modelling toolkit and game engine, and featured not only an interactive 3D editor for underwater scenario generation by instructors, but also a real-time, 3D After Action Review (AAR system for formative assessment and feedback. The simulated scenarios and AAR architecture were based on early human factors observations and briefings conducted at the UK's Defence Diving School (DDS, an organisation that provides basic military diving training for all Royal Navy and Army (Royal Engineers divers. An experimental pilot study was undertaken to determine whether or not basic navigational and mine detection components of diver performance could be improved as a result of exposing participants to the AAR system, delivered between simulated diving scenarios. The results suggest that the provision of AAR was accompanied by significant performance improvements in the positive identification of simulated underwater ordnance (in contrast to non-ordnance objects and on participants' description of their location, their immediate in-water or seabed context and their structural condition. Only marginal improvements were found with participants' navigational performance in terms of their deviation accuracies from a pre-programmed expert search path. Overall, this project contributes to the growing corpus of evidence supporting the development of simulators that demonstrate the value of exploiting open source gaming software and the significance of adopting established games design

  19. Performance Evaluation of New Joint EDF-RM Scheduling Algorithm for Real Time Distributed System

    Directory of Open Access Journals (Sweden)

    Rashmi Sharma

    2014-01-01

    Full Text Available In Real Time System, the achievement of deadline is the main target of every scheduling algorithm. Earliest Deadline First (EDF, Rate Monotonic (RM, and least Laxity First are some renowned algorithms that work well in their own context. As we know, there is a very common problem Domino's effect in EDF that is generated due to overloading condition (EDF is not working well in overloading situation. Similarly, performance of RM is degraded in underloading condition. We can say that both algorithms are complements of each other. Deadline missing in both events happens because of their utilization bounding strategy. Therefore, in this paper we are proposing a new scheduling algorithm that carries through the drawback of both existing algorithms. Joint EDF-RM scheduling algorithm is implemented in global scheduler that permits task migration mechanism in between processors in the system. In order to check the improved behavior of proposed algorithm we perform simulation. Results are achieved and evaluated in terms of Success Ratio (SR, Average CPU Utilization (ECU, Failure Ratio (FR, and Maximum Tardiness parameters. In the end, the results are compared with the existing (EDF, RM, and D_R_EDF algorithms. It has been shown that the proposed algorithm performs better during overloading condition as well in underloading condition.

  20. A real time study on condition monitoring of distribution transformer using thermal imager

    Science.gov (United States)

    Mariprasath, T.; Kirubakaran, V.

    2018-05-01

    The transformer is one of the critical apparatus in the power system. At any cost, a few minutes of outages harshly influence the power system. Hence, prevention-based maintenance technique is very essential. The continuous conditioning and monitoring technology significantly increases the life span of the transformer, as well as reduces the maintenance cost. Hence, conditioning and monitoring of transformer's temperature are very essential. In this paper, a critical review has been made on various conditioning and monitoring techniques. Furthermore, a new method, hot spot indication technique, is discussed. Also, transformer's operating condition is monitored by using thermal imager. From the thermal analysis, it is inferred that major hotspot locations are appearing at connection lead out; also, the bushing of the transformer is the very hottest spot in transformer, so monitoring the level of oil is essential. Alongside, real time power quality analysis has been carried out using the power analyzer. It shows that industrial drives are injecting current harmonics to the distribution network, which causes the power quality problem on the grid. Moreover, the current harmonic limit has exceeded the IEEE standard limit. Hence, the adequate harmonics suppression technique is need an hour.

  1. State of the art on fault-tolerant real time distributed systems

    International Nuclear Information System (INIS)

    Levkov, V.

    1992-06-01

    The integration of new computerized functions in power plant, and especially nuclear power plant, control and instrumentation systems implies more and more stringent requirements as to communication system reliability. For if an item of equipment, or even a computer program, can be validated and qualified, no formal qualification procedure is presently imposed on communication networks. This is certainly due to the relative immaturity of these networks, but also to their complexity. It is for this reason that, in the context of preparation for the future PWR 2000 standardized nuclear plants, it would seem appropriate to take a look at fault-tolerant communication systems. Since C and I type applications (in the control room) are divided between several computers and are required to contend with extremely severe time constraints, EDF has undertaken investigation of fault-tolerant, real time distributed systems. This paper summarized the state of the art in the field as it appears from discussion with computer manufacturers, academics and research workers on related projects. The results obtained were then used to determine trends as to ''promising'' solutions. The paper concludes with recommended study programs for the PCC department of EDF/R and DD for the next few years. (author), 9 figs., 10 refs., 2 annexes

  2. Measurement of density distribution of fluids by real-time holographic interferometer using lenticular lens

    International Nuclear Information System (INIS)

    Sakurai, Katsumi; Okamoto, Koji; Kato, Fumitake; Shimizu, Isao

    1998-01-01

    The three-dimensional density distribution could be measured using the computer tomography technique with interferogram image. The photoconductor-plastic hologram (PPH) is a new hologram device which can easily make the hologram for the real-time interferometer. Since the image contains 2D information, lots of images taken from different angles should be needed to reconstruct the 3D information. However, the optics configuration will be too complex to obtain the multi-directional image simultaneously, even in the PPH system. Using the diffusion plate, the laser light could be diffused to multi-direction. When the hologram is recorded with the diffused laser, the multi-directional image can be obtained using only one hologram plate. In the computer tomography technique, only the holizontal direction is effective, while the diffused laser contains the whole direction, causing the noise on the hologram. In this study, the lenticular lens is used as the diffusion plate. The lenticular lens reflects the laser only in horizontal direction without the vertical (non-horizontal) direction. Therefore the multi-directional fringe images could be clearly obtained. In the experiment the helium jet was measured to demonstrate the effectiveness of the proposed system. (author)

  3. A comprehensive cloud-based real-time simulation framework for oblivious power routing in clusters of DC microgrids

    DEFF Research Database (Denmark)

    Amini, M. Hadi; Boroojeni, Kianoosh G.; Dragicevic, Tomislav

    2017-01-01

    of microgrids. The effectiveness of the proposed algorithm has been verified in MATLAB simulation. Furthermore, we propose a comprehensive simulation platform for further implementation of the proposed strategy on OPAL-RT real-time simulator system (RTDS). In our proposed platform, the communication path...

  4. Deterministic one-way simulation of two-way, real-time cellular automata and its related problems

    Energy Technology Data Exchange (ETDEWEB)

    Umeo, H; Morita, K; Sugata, K

    1982-06-13

    The authors show that for any deterministic two-way, real-time cellular automaton, m, there exists a deterministic one-way cellular automation which can simulate m in twice real-time. Moreover the authors present a new type of deterministic one-way cellular automata, called circular cellular automata, which are computationally equivalent to deterministic two-way cellular automata. 7 references.

  5. Systems-on-chip approach for real-time simulation of wheel-rail contact laws

    Science.gov (United States)

    Mei, T. X.; Zhou, Y. J.

    2013-04-01

    This paper presents the development of a systems-on-chip approach to speed up the simulation of wheel-rail contact laws, which can be used to reduce the requirement for high-performance computers and enable simulation in real time for the use of hardware-in-loop for experimental studies of the latest vehicle dynamic and control technologies. The wheel-rail contact laws are implemented using a field programmable gate array (FPGA) device with a design that substantially outperforms modern general-purpose PC platforms or fixed architecture digital signal processor devices in terms of processing time, configuration flexibility and cost. In order to utilise the FPGA's parallel-processing capability, the operations in the contact laws algorithms are arranged in a parallel manner and multi-contact patches are tackled simultaneously in the design. The interface between the FPGA device and the host PC is achieved by using a high-throughput and low-latency Ethernet link. The development is based on FASTSIM algorithms, although the design can be adapted and expanded for even more computationally demanding tasks.

  6. Development and validation of real-time simulation of X-ray imaging with respiratory motion.

    Science.gov (United States)

    Vidal, Franck P; Villard, Pierre-Frédéric

    2016-04-01

    We present a framework that combines evolutionary optimisation, soft tissue modelling and ray tracing on GPU to simultaneously compute the respiratory motion and X-ray imaging in real-time. Our aim is to provide validated building blocks with high fidelity to closely match both the human physiology and the physics of X-rays. A CPU-based set of algorithms is presented to model organ behaviours during respiration. Soft tissue deformation is computed with an extension of the Chain Mail method. Rigid elements move according to kinematic laws. A GPU-based surface rendering method is proposed to compute the X-ray image using the Beer-Lambert law. It is provided as an open-source library. A quantitative validation study is provided to objectively assess the accuracy of both components: (i) the respiration against anatomical data, and (ii) the X-ray against the Beer-Lambert law and the results of Monte Carlo simulations. Our implementation can be used in various applications, such as interactive medical virtual environment to train percutaneous transhepatic cholangiography in interventional radiology, 2D/3D registration, computation of digitally reconstructed radiograph, simulation of 4D sinograms to test tomography reconstruction tools. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Study of Real-Time Programming for Simulation of Nuclear Reactor Dynamics

    International Nuclear Information System (INIS)

    Aliq; Widi Setiawan; Hendro Tjahjono

    2003-01-01

    Many aspects of real-time system are reviewed including the method, programming techniques, and its possibility to be applied in research reactor. The main point of real-time system is that it must designed to have a characteristics not only fast response but the most important is on-time response. In order to cover this requirements, real-time system need also a simple operating system consist of a kernel and application software. At the level of programming, real-time system require a modular approach, hard and soft time division and interprocess communications. The implementation can include some real-time (RT) operation system such as: RT-Linux, RT-OS9 and RT-Mat lab. Because of fast and on-time response requirements, if this system is going to be applied to research reactor, the transfer function model maybe more appropriate model compared to point kinetics model for the reason of computation time. (author)

  8. Real-time digital simulation of power electronics systems with Neutral Point Piloted multilevel inverter using FPGA

    Energy Technology Data Exchange (ETDEWEB)

    Rakotozafy, Mamianja [Groupe de Recherches en Electrotechnique et Electronique de Nancy (GREEN), Faculte des Sciences et Techniques, BP 70239, 54506 Vandoeuvre Cedex (France); CONVERTEAM SAS, Parc d' activites Techn' hom, 24 avenue du Marechal Juin, BP 40437, 90008 Belfort Cedex (France); Poure, Philippe [Laboratoire d' Instrumentation Electronique de Nancy (LIEN), Faculte des Sciences et Techniques, BP 70239, 54506 Vandoeuvre Cedex (France); Saadate, Shahrokh [Groupe de Recherches en Electrotechnique et Electronique de Nancy (GREEN), Faculte des Sciences et Techniques, BP 70239, 54506 Vandoeuvre Cedex (France); Bordas, Cedric; Leclere, Loic [CONVERTEAM SAS, Parc d' activites Techn' hom, 24 avenue du Marechal Juin, BP 40437, 90008 Belfort Cedex (France)

    2011-02-15

    Most of actual real time simulation platforms have practically about ten microseconds as minimum calculation time step, mainly due to computation limits such as processing speed, architecture adequacy and modeling complexities. Therefore, simulation of fast switching converters' instantaneous models requires smaller computing time step. The approach presented in this paper proposes an answer to such limited modeling accuracies and computational bandwidth of the currently available digital simulators.As an example, the authors present a low cost, flexible and high performance FPGA-based real-time digital simulator for a complete complex power system with Neutral Point Piloted (NPP) three-level inverter. The proposed real-time simulator can model accurately and efficiently the complete power system, reducing costs, physical space and avoiding any damage to the actual equipment in the case of any dysfunction of the digital controller prototype. The converter model is computed at a small fixed time step as low as 100 ns. Such a computation time step allows high precision account of the gating signals and thus avoids averaging methods and event compensations. Moreover, a novel high performance model of the NPP three-level inverter has also been proposed for FPGA implementation. The proposed FPGA-based simulator models the environment of the NPP converter: the dc link, the RLE load and the digital controller and gating signals. FPGA-based real time simulation results are presented and compared with offline results obtained using PLECS software. They validate the efficiency and accuracy of the modeling for the proposed high performance FPGA-based real-time simulation approach. This paper also introduces new potential FPGA-based applications such as low cost real time simulator for power systems by developing a library of flexible and portable models for power converters, electrical machines and drives. (author)

  9. Real-time 3D radiation risk assessment supporting simulation of work in nuclear environments

    International Nuclear Information System (INIS)

    Szoke, I; Louka, M N; Bryntesen, T R; Bratteli, J; Edvardsen, S T; RøEitrheim, K K; Bodor, K

    2014-01-01

    This paper describes the latest developments at the Institute for Energy Technology (IFE) in Norway, in the field of real-time 3D (three-dimensional) radiation risk assessment for the support of work simulation in nuclear environments. 3D computer simulation can greatly facilitate efficient work planning, briefing, and training of workers. It can also support communication within and between work teams, and with advisors, regulators, the media and public, at all the stages of a nuclear installation’s lifecycle. Furthermore, it is also a beneficial tool for reviewing current work practices in order to identify possible gaps in procedures, as well as to support the updating of international recommendations, dissemination of experience, and education of the current and future generation of workers. IFE has been involved in research and development into the application of 3D computer simulation and virtual reality (VR) technology to support work in radiological environments in the nuclear sector since the mid 1990s. During this process, two significant software tools have been developed, the VRdose system and the Halden Planner, and a number of publications have been produced to contribute to improving the safety culture in the nuclear industry. This paper describes the radiation risk assessment techniques applied in earlier versions of the VRdose system and the Halden Planner, for visualising radiation fields and calculating dose, and presents new developments towards implementing a flexible and up-to-date dosimetric package in these 3D software tools, based on new developments in the field of radiation protection. The latest versions of these 3D tools are capable of more accurate risk estimation, permit more flexibility via a range of user choices, and are applicable to a wider range of irradiation situations than their predecessors. (paper)

  10. Real-time 3D radiation risk assessment supporting simulation of work in nuclear environments.

    Science.gov (United States)

    Szőke, I; Louka, M N; Bryntesen, T R; Bratteli, J; Edvardsen, S T; RøEitrheim, K K; Bodor, K

    2014-06-01

    This paper describes the latest developments at the Institute for Energy Technology (IFE) in Norway, in the field of real-time 3D (three-dimensional) radiation risk assessment for the support of work simulation in nuclear environments. 3D computer simulation can greatly facilitate efficient work planning, briefing, and training of workers. It can also support communication within and between work teams, and with advisors, regulators, the media and public, at all the stages of a nuclear installation's lifecycle. Furthermore, it is also a beneficial tool for reviewing current work practices in order to identify possible gaps in procedures, as well as to support the updating of international recommendations, dissemination of experience, and education of the current and future generation of workers.IFE has been involved in research and development into the application of 3D computer simulation and virtual reality (VR) technology to support work in radiological environments in the nuclear sector since the mid 1990s. During this process, two significant software tools have been developed, the VRdose system and the Halden Planner, and a number of publications have been produced to contribute to improving the safety culture in the nuclear industry.This paper describes the radiation risk assessment techniques applied in earlier versions of the VRdose system and the Halden Planner, for visualising radiation fields and calculating dose, and presents new developments towards implementing a flexible and up-to-date dosimetric package in these 3D software tools, based on new developments in the field of radiation protection. The latest versions of these 3D tools are capable of more accurate risk estimation, permit more flexibility via a range of user choices, and are applicable to a wider range of irradiation situations than their predecessors.

  11. Real-time surgical simulation for deformable soft-tissue objects with a tumour using Boundary Element techniques

    Science.gov (United States)

    Wang, P.; Becker, A. A.; Jones, I. A.; Glover, A. T.; Benford, S. D.; Vloeberghs, M.

    2009-08-01

    A virtual-reality real-time simulation of surgical operations that incorporates the inclusion of a hard tumour is presented. The software is based on Boundary Element (BE) technique. A review of the BE formulation for real-time analysis of two-domain deformable objects, using the pre-solution technique, is presented. The two-domain BE software is incorporated into a surgical simulation system called VIRS to simulate the initiation of a cut on the surface of the soft tissue and extending the cut deeper until the tumour is reached.

  12. Real-time surgical simulation for deformable soft-tissue objects with a tumour using Boundary Element techniques

    International Nuclear Information System (INIS)

    Wang, P; Becker, A A; Jones, I A; Glover, A T; Benford, S D; Vloeberghs, M

    2009-01-01

    A virtual-reality real-time simulation of surgical operations that incorporates the inclusion of a hard tumour is presented. The software is based on Boundary Element (BE) technique. A review of the BE formulation for real-time analysis of two-domain deformable objects, using the pre-solution technique, is presented. The two-domain BE software is incorporated into a surgical simulation system called VIRS to simulate the initiation of a cut on the surface of the soft tissue and extending the cut deeper until the tumour is reached.

  13. Advanced Research and Education in Electrical Drives by Using Digital Real-Time Hardware-in-the-Loop Simulation

    DEFF Research Database (Denmark)

    Bojoi, R.; Profumo, F.; Griva, G.

    2002-01-01

    The authors present in this paper a digital real-time hardware-in-the-loop simulation of a three-phase induction motor drive. The main real-time simulation tool is the dSPACE DS1103 PPC Controller Board which simulates the power and signal conditioning parts. The control algorithm of the virtual...... drive has been implemented on the Evaluation Board of TMS320F240 DSP. The experimental results validate this solution as a powerful tool to be used in research and advanced education. Thus, the students can put in practic the theory without spending too much time with details concerning the hardware...

  14. Operational characteristic analysis of conduction cooling HTS SMES for Real Time Digital Simulator based power quality enhancement simulation

    International Nuclear Information System (INIS)

    Kim, A.R.; Kim, G.H.; Kim, K.M.; Kim, D.W.; Park, M.; Yu, I.K.; Kim, S.H.; Sim, K.; Sohn, M.H.; Seong, K.C.

    2010-01-01

    This paper analyzes the operational characteristics of conduction cooling Superconducting Magnetic Energy Storage (SMES) through a real hardware based simulation. To analyze the operational characteristics, the authors manufactured a small-scale toroidal-type SMES and implemented a Real Time Digital Simulator (RTDS) based power quality enhancement simulation. The method can consider not only electrical characteristics such as inductance and current but also temperature characteristic by using the real SMES system. In order to prove the effectiveness of the proposed method, a voltage sag compensation simulation has been implemented using the RTDS connected with the High Temperature Superconducting (HTS) model coil and DC/DC converter system, and the simulation results are discussed in detail.

  15. Generation of real-time global ionospheric map based on the global GNSS stations with only a sparse distribution

    Science.gov (United States)

    Li, Zishen; Wang, Ningbo; Li, Min; Zhou, Kai; Yuan, Yunbin; Yuan, Hong

    2017-04-01

    The Earth's ionosphere is part of the atmosphere stretching from an altitude of about 50 km to more than 1000 km. When the Global Navigation Satellite System (GNSS) signal emitted from a satellite travels through the ionosphere before reaches a receiver on or near the Earth surface, the GNSS signal is significantly delayed by the ionosphere and this delay bas been considered as one of the major errors in the GNSS measurement. The real-time global ionospheric map calculated from the real-time data obtained by global stations is an essential method for mitigating the ionospheric delay for real-time positioning. The generation of an accurate global ionospheric map generally depends on the global stations with dense distribution; however, the number of global stations that can produce the real-time data is very limited at present, which results that the generation of global ionospheric map with a high accuracy is very different when only using the current stations with real-time data. In view of this, a new approach is proposed for calculating the real-time global ionospheric map only based on the current stations with real-time data. This new approach is developed on the basis of the post-processing and the one-day predicted global ionospheric map from our research group. The performance of the proposed approach is tested by the current global stations with the real-time data and the test results are also compared with the IGS-released final global ionospheric map products.

  16. Timing system solution for MedAustron; Real-time event and data distribution network

    International Nuclear Information System (INIS)

    Stefanic, R.; Tavcar, R.; Dedic, J.; Gutleber, J.; Moser, R.

    2012-01-01

    MedAustron is an ion beam research and therapy centre under construction in Wiener Neustadt, Austria. The facility features a synchrotron particle accelerator for light ions. The timing system for this class of accelerators has been developed in close collaboration between MedAustron and Cosylab. Mitigating economical and technological risks, we have chosen a proven, widely used Micro Research Finland (MRF) timing equipment and redesigned its FPGA firmware, extending its high-logic services above transport layer, as required by machine specifics. We obtained a generic real-time broadcast network for coordinating actions of a compact, pulse-to-pulse modulation based particle accelerator. High-level services include support for virtual accelerators and a rich selection of event response mechanisms. The system uses a combination of a real-time link for downstream events and a non-real-time link for upstream messaging and non time-critical communication. It comes with National Instruments LabVIEW-based software support, ready to be integrated into PXIe based front-end controllers. This article explains the high level logic services provided by the real-time link, describes the non-real-time interfaces and presents the software configuration mechanisms. (authors)

  17. NCU-SWIP Space Weather Instrumentation Payload - Intelligent Sensors On Efficient Real-Time Distributed LUTOS

    Science.gov (United States)

    Yeh, Tse-Liang; Dmitriev, Alexei; Chu, Yen-Hsyang; Jiang, Shyh-Biau; Chen, Li-Wu

    The NCU-SWIP - Space Weather Instrumentation Payload is developed for simultaneous in-situ and remote measurement of space weather parameters for cross verifications. The measurements include in-situ electron density, electron temperature, magnetic field, the deceleration of satellite due to neutral wind, and remotely the linear cumulative intensities of oxygen ion air-glows at 135.6nm and 630.0nm along the flight path in forward, nader, and backward directions for tomographic reconstruction of the electron density distribution underneath. This instrument package is suitable for micro satellite constellation to establish nominal space weather profiles and, thus, to detect abnormal variations as the signs of ionospheric disturbances induced by severe atmospheric weather, or earth quake - mantle movement through their Lithosphere-Atmosphere-Ionosphere Coupling Mechanism. NCU-SWIP is constructed with intelligent sensor modules connected by common bus with their functionalities managed by an efficient distributed real-time system LUTOS. The same hierarchy can be applied to the level of satellite constellation. For example SWIP's in a constellation in coordination with the GNSS Occultation Experiment TriG planned for the Formosa-7 constellation, data can be cross correlated for verification and refinement for real-time, stable and reliable measurements. A SWIP will be contributed to the construction of a MAI Micro Satellite for verification. The SWIP consists of two separate modules: the SWIP main control module and the SWIP-PMTomo sensor module. They are respectively a 1.5kg W120xL120xH100 (in mm) box with forward facing 120mmPhi circular disk probe on a boom top edged at 470mm height and a 7.2kg W126xL590x372H (in mm) slab containing 3 legs looking downwards along the flight path, while consuming the maximum electricity of 10W and 12W. The sensors are 1) ETPEDP measuring 16bits floating potentials for electron temperature range of 1000K to 3000K and 24bits electron

  18. Realistic RF system and Beam Simulation in Real Time for a Synchrotron

    CERN Document Server

    Tückmantel, Joachim

    2001-01-01

    Due to heavy beam loading with gaps in the LHC beams, RF and beam are intimately linked to a complex system with fast transients where the RF loops and their limitations play a decisive role. Such a system is difficult to assess with analytical methods. To learn about overall system stability and for the definition of RF components to be built it is essential to understand the complete system long before the machine really exists. Therefore the author has written a general purpose real time simulation program and applied it to model the LHC machine with its beam pattern and complete double RF system. The latter is equipped with fast RF vector feedback loops having loop delay, transmitter power limitation and limited amplifier bandwidth as well as including one-turn-delay feedback and longitudinal batch injection damping. The development of all RF and beam quantities can be displayed graphically turn by turn. These frames can be assembled to a realistic multi-trace scope movie.

  19. An electronic system for simulation of neural networks with a micro-second real time constraint

    International Nuclear Information System (INIS)

    Chorti, Arsenia; Granado, Bertrand; Denby, Bruce; Garda, Patrick

    2001-01-01

    Neural networks implemented in hardware can perform pattern recognition very quickly, and as such have been used to advantage in the triggering systems of certain high energy physics experiments. Typically, time constants of the order of a few microseconds are required. In this paper, we present a new system. MAHARADJA, for evaluating MLP and RBF neural network paradigms in real time. The system is tested on a possible ATLAS muon triggering application suggested by the Tel Aviv ATLAS group, consisting of a 4-8-8-4 MLP which must be evaluated in 10 microseconds. The inputs to the net are dx/dz, x(z=0), dy/dz, and y(z=0), whereas the outputs give pt, tan(phi), sin(theta), and q, the charge. With a 10 MHz clock, MAHARADJA calculates the result in 6.8 microseconds; at 20 MHz, which is readily attainable, this would be reduced to only 3.4 microseconds. The system can also handle RBF networks with 3 different distance metrics (Euclidean, Manhattan and Mahalanobis), and can simulate any MLP of 10 hidden layers or less. The electronic implementation is with FPGA's, which can be optimized for a specific neural network because the number of processing elements can be modified

  20. Real-time simulation of the retina allowing visualization of each processing stage

    Science.gov (United States)

    Teeters, Jeffrey L.; Werblin, Frank S.

    1991-08-01

    The retina computes to let us see, but can we see the retina compute? Until now, the answer has been no, because the unconscious nature of the processing hides it from our view. Here the authors describe a method of seeing computations performed throughout the retina. This is achieved by using neurophysiological data to construct a model of the retina, and using a special-purpose image processing computer (PIPE) to implement the model in real time. Processing in the model is organized into stages corresponding to computations performed by each retinal cell type. The final stage is the transient (change detecting) ganglion cell. A CCD camera forms the input image, and the activity of a selected retinal cell type is the output which is displayed on a TV monitor. By changing the retina cell driving the monitor, the progressive transformations of the image by the retina can be observed. These simulations demonstrate the ubiquitous presence of temporal and spatial variations in the patterns of activity generated by the retina which are fed into the brain. The dynamical aspects make these patterns very different from those generated by the common DOG (Difference of Gaussian) model of receptive field. Because the retina is so successful in biological vision systems, the processing described here may be useful in machine vision.

  1. Combination of Robot Simulation with Real-time Monitoring and Control

    Directory of Open Access Journals (Sweden)

    Jianyu YANG

    2014-08-01

    Full Text Available The paper mainly focuses in combining virtual reality based operation simulation with remote real-time monitoring and control method for an experimental robot. A system composition framework was designed and relative arm-wheel experimental robot platform was also built. Virtual robots and two virtual environments were developed. To locate the virtual robot within numerical environments, relative mathematical methods is also discussed, including analytic locating methods for linear motion and self-rotation, as well as linear transformation method with homogeneous matrices for turning motion, in order to decrease division calculations. Several experiments were carried out, trajectory errors were found because of relative slides between the wheel and the floor, during the locating experiments. Writing-monitoring experiments were also performed by programming the robotic arm to write a Chinese character, and the virtual robot in monitoring terminal perfectly followed all the movements. All the experiment results confirmed that virtual environment can not only be used as a good supplement to the traditional video monitoring method, but also offer better control experience during the operation.

  2. Faster-Than-Real-Time Simulation of Lithium Ion Batteries with Full Spatial and Temporal Resolution

    Directory of Open Access Journals (Sweden)

    Sandip Mazumder

    2013-01-01

    Full Text Available A one-dimensional coupled electrochemical-thermal model of a lithium ion battery with full temporal and normal-to-electrode spatial resolution is presented. Only a single pair of electrodes is considered in the model. It is shown that simulation of a lithium ion battery with the inclusion of detailed transport phenomena and electrochemistry is possible with faster-than-real-time compute times. The governing conservation equations of mass, charge, and energy are discretized using the finite volume method and solved using an iterative procedure. The model is first successfully validated against experimental data for both charge and discharge processes in a LixC6-LiyMn2O4 battery. Finally, it is demonstrated for an arbitrary rapidly changing transient load typical of a hybrid electric vehicle drive cycle. The model is able to predict the cell voltage of a 15-minute drive cycle in less than 12 seconds of compute time on a laptop with a 2.33 GHz Intel Pentium 4 processor.

  3. Real-Time Measurement of Electronic Cigarette Aerosol Size Distribution and Metals Content Analysis.

    Science.gov (United States)

    Mikheev, Vladimir B; Brinkman, Marielle C; Granville, Courtney A; Gordon, Sydney M; Clark, Pamela I

    2016-09-01

    Electronic cigarette (e-cigarette) use is increasing worldwide and is highest among both daily and nondaily smokers. E-cigarettes are perceived as a healthier alternative to combustible tobacco products, but their health risk factors have not yet been established, and one of them is lack of data on aerosol size generated by e-cigarettes. We applied a real-time, high-resolution aerosol differential mobility spectrometer to monitor the evolution of aerosol size and concentration during puff development. Particles generated by e-cigarettes were immediately delivered for analysis with minimal dilution and therefore with minimal sample distortion, which is critically important given the highly dynamic aerosol/vapor mixture inherent to e-cigarette emissions. E-cigarette aerosols normally exhibit a bimodal particle size distribution: nanoparticles (11-25nm count median diameter) and submicron particles (96-175nm count median diameter). Each mode has comparable number concentrations (10(7)-10(8) particles/cm(3)). "Dry puff" tests conducted with no e-cigarette liquid (e-liquid) present in the e-cigarette tank demonstrated that under these conditions only nanoparticles were generated. Analysis of the bulk aerosol collected on the filter showed that e-cigarette emissions contained a variety of metals. E-cigarette aerosol size distribution is different from that of combustible tobacco smoke. E-cigarettes generate high concentrations of nanoparticles and their chemical content requires further investigation. Despite the small mass of nanoparticles, their toxicological impact could be significant. Toxic chemicals that are attached to the small nanoparticles may have greater adverse health effects than when attached to larger submicron particles. The e-cigarette aerosol size distribution is different from that of combustible tobacco smoke and typically exhibits a bimodal behavior with comparable number concentrations of nanoparticles and submicron particles. While vaping the e

  4. Timing System Solution for MedAustron; Real-time Event and Data Distribution Network

    CERN Document Server

    Štefanič, R; Dedič, J; Gutleber, J; Moser, R

    2011-01-01

    MedAustron is an ion beam research and therapy centre under construction in Wiener Neustadt, Austria. The facility features a synchrotron particle accelerator for light ions. The timing system for this class of accelerators has been developed in close collaboration between MedAustron and Cosylab. Mitigating economical and technological risks, we have chosen a proven, widely used Micro Research Finland (MRF) timing equipment and redesigned its FPGA firmware, extending its high-logic services above transport layer, as required by machine specifics. We obtained a generic real-time broadcast network for coordinating actions of a compact, pulse-to-pulse modulation based particle accelerator. High-level services include support for virtual accelerators and a rich selection of event response mechanisms. The system uses a combination of a real-time link for downstream events and a non-real-time link for upstream messaging and non time-critical communication. It comes with National Instruments LabVI...

  5. Developing a Tool Point Control Scheme for a Hydraulic Crane Using Interactive Real-time Dynamic Simulation

    DEFF Research Database (Denmark)

    Pedersen, Mikkel Melters; Hansen, Michael Rygaard; Ballebye, Morten

    2010-01-01

    This paper describes the implementation of an interactive real-time dynamic simulation model of a hydraulic crane. The user input to the model is given continuously via joystick and output is presented continuously in a 3D animation. Using this simulation model, a tool point control scheme...... is developed for the specific crane, considering the saturation phenomena of the system and practical implementation....

  6. On the Designing of Model Checkers for Real-Time Distributed Systems

    Directory of Open Access Journals (Sweden)

    D. Yu. Volkanov

    2012-01-01

    Full Text Available To verify real-time properties of UML statecharts one may apply a UPPAAL, toolbox for model checking of real-time systems. One of the most suitable ways to specify an operational semantics of UML statecharts is to invoke the formal model of Hierarchical Timed Automata. Since the model language of UPPAAL is based on Networks of Timed Automata one has to provide a conversion of Hierarchical Timed Automata to Networks of Timed Automata. In this paper we describe this conversion algorithm and prove that it is correct w.r.t. UPPAAL query language which is based on the subset of Timed CTL.

  7. Acquisition of a Multi-Domain Advanced Real-Time Simulator to Support DoD-focused Interdisciplinary Research at CSUB

    Science.gov (United States)

    2017-10-17

    SECURITY CLASSIFICATION OF: 1. REPORT DATE (DD-MM-YYYY) 4. TITLE AND SUBTITLE 13. SUPPLEMENTARY NOTES 12. DISTRIBUTION AVAILIBILITY STATEMENT 6...0704-0188 3. DATES COVERED (From - To) - Approved for public release; distribution is unlimited. UU UU UU UU 17-10-2017 25-Jul-2016 24-Jul-2017 Final...Report: Acquisition of a Multi-Domain Advanced Real- Time Simulator to Support DoD-focused Interdisciplinary Research at CSUB The views, opinions and

  8. Real-time measurements to characterize dynamics of emulsion interface during simulated intestinal digestion.

    Science.gov (United States)

    Pan, Yuanjie; Nitin, N

    2016-05-01

    Efficient delivery of bioactives remains a critical challenge due to their limited bioavailability and solubility. While many encapsulation systems are designed to modulate the digestion and release of bioactives within the human gastrointestinal tract, there is limited understanding of how engineered structures influence the delivery of bioactives. The objective of this study was to develop a real-time quantitative method to measure structural changes in emulsion interface during simulated intestinal digestion and to correlate these changes with the release of free fatty acids (FFAs). Fluorescence resonant energy transfer (FRET) was used for rapid in-situ measurement of the structural changes in emulsion interface during simulated intestinal digestion. By using FRET, changes in the intermolecular spacing between the two different fluorescent probes labeled emulsifier were characterized. Changes in FRET measurements were compared with the release of FFAs. The results showed that bile salts and pancreatic lipase interacted immediately with the emulsion droplets and disrupted the emulsion interface as evidenced by reduction in FRET efficacy compared to the control. Similarly, a significant amount of FFAs was released during digestion. Moreover, addition of a second layer of polymers at emulsion interface decreased the extent of interface disruption by bile salts and pancreatic lipase and impacted the amount or rate of FFA release during digestion. These results were consistent with the lower donor/acceptor ratio of the labeled probes from the FRET result. Overall, this study provides a novel approach to analyze the dynamics of emulsion interface during digestion and their relationship with the release of FFAs. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. SOSPO-SP: Secure Operation of Sustainable Power Systems Simulation Platform for Real-Time System State Evaluation and Control

    DEFF Research Database (Denmark)

    Morais, Hugo; Vancraeyveld, Pieter; Pedersen, Allan Henning Birger

    2014-01-01

    Measurement Units (PMUs) provides more information and enables wide-area monitoring with accurate timing. One of the challenges in the near future is converting the high quantity and quality of information provided by PMUs into useful knowledge about operational state of a global system. The use of real-time...... simulation in closed-loop is essential to develop and validate new real-time applications of wide-area PMU data. This paper presents a simulation platform developed within the research project Secure Operation of Sustainable Power Systems (SOSPO). The SOSPO simulation platform (SOSPO-SP) functions...... in a closed-loop, integrating new real-time assessment methods to provide useful information to operators in power system control centers and to develop new control methodologies that handle emergency situations and avoid power system blackouts....

  10. Strategy-making for a proactive distribution company in the real-time market with demand response

    DEFF Research Database (Denmark)

    Zhang, Chunyu; Wang, Qi; Wang, Jianhui

    2016-01-01

    This paper proposes a methodology to optimize the trading strategies of a proactive distribution company (PDISCO) in the real-time market by mobilizing the demand response. Each distribution-level demand is considered as an elastic one. To capture the interrelation between the PDISCO and the real......-time market, a bi-level model is presented for the PDISCO to render continuous offers and bids strategically. The upper level problem expresses the PDISCO's profit maximization, while the lower-level problem minimizes the operation cost of the transmission-level real-time market. To solve the proposed model......, a primal-dual approach is used to translate this bi-level model into a single-level mathematical program with equilibrium constraints. Results of case studies are reported to show the effectiveness of the proposed model. (C) 2016 Elsevier Ltd. All rights reserved....

  11. Distributed digital real-time control system for the TCV tokamak and its applications

    NARCIS (Netherlands)

    Anand, H.; Galperti, C.; Coda, S.; Duval, B.P.; Felici, F.; Blanken, T.; Maljaars, E.; Moret, J.M.; Sauter, O.; Goodman, T.P.; Kim, D.

    2017-01-01

    A key feature of the new digital plasma control system installed on the TCV (Tokamak à Configuration Variable) tokamak is its possibility to rapidly design, test and deploy real-time algorithms. It accommodates hundreds of diagnostic inputs and actuator outputs, and offers the possibility to design

  12. On a fast numerical tool for nuclear accidental dynamic phenomenology and application to the real time simulation of Lady Godiva

    International Nuclear Information System (INIS)

    Bindel, Laurent; Gamess, Andre; Jasserand, Frederic; Laporte, Sebastien

    2003-01-01

    This paper present a modern numerical method, implemented in a TUI-code named MacDSP, for solving any set of differential equations and in particular phenomenological accidental dynamic calculations. The speed efficiency of such an approach, thanks to the use of the hybrid-level power offered by C++ and an ad-hoc design, make it possible to construct the first kid of a family of real time simulator employing the video games technology DirectX TM : Lady Godiva Real Time Simulator. (author)

  13. Simulation of Vibrations in Real Time Plane Milling with Spindle Speed Correction

    Directory of Open Access Journals (Sweden)

    I. I. Ivanov

    2017-01-01

    Full Text Available In milling the hard-to-machine materials vibrations (chatter often arise from the high cutting forces if a technological system is insufficiently rigid.The main way to suppress these vibrations is to increase a stiffness of the mounting system of the tool and the work-piece to be machined. However, sometimes this method doesn’t lead to desirable result because of high values of intrinsic pliability of the tool and the work-piece. Currently, there are more complicated methods to ensure milling process quality. Among them there are three main groups:mathematical simulation of milling process dynamics and computation of processing parameters which provide high quality of machined surface, low level of vibrations and static deflections of a tool and a work-piece;introduction of the active vibration suppression devices into machine tool design; such devices include a vibration sensor, a feedback circuit, and an actuator which induces kinematic or force action on the oscillatory system;control of processing parameters, mainly of rotation frequency for minimizing the amplitudes of vibrations.The paper studies one of the 3rd group methods. There is a suggestion to process a signal of vibrational accelerations in real time and detect a chatter onset. If the chatter has been detected its frequency is to be identified, and the new value of rotation speed is set:where Ω – rotation frequency, rot/s; p – the tool eigenfrequency value identified during processing, Hz; z – mill tooth number; i – positive integer number; ε<1 – small positive parameter. In the current research it is assumed that ε = 0,2.The formula has been chosen because at the rotation frequency axis where tooth pass frequency is slightly less than the eigenfrequency divided by the integer value there are stable zones of dynamics in the milling process.The study shows a developed model of the plane milling dynamics. It includes a dynamic model of the tool, a model of cutting

  14. Formal methods and tools for the development of distributed and real time systems : Esprit Project 3096 (SPEC)

    NARCIS (Netherlands)

    Roever, de W.P.; Barringer, H.; Courcoubetis, C.; Gabbay, D.M.; Gerth, R.T.; Jonsson, B.; Pnueli, A.; Reed, M.; Sifakis, J.; Vytopil, J.; Wolper, P.

    1990-01-01

    The Basic Research Action No. 3096, Formal Methods snd Tools for the Development of Distributed and Real Time Systems, is funded in the Area of Computer Science, under the ESPRIT Programme of the European Community. The coordinating institution is the Department of Computing Science, Eindhoven

  15. The response-time distribution in a real-time database with optimistic concurrency control and constant execution times

    NARCIS (Netherlands)

    Sassen, S.A.E.; Wal, van der J.

    1997-01-01

    For a real-time shared-memory database with optimistic concurrency control, an approximation for the transaction response-time distribution is obtained. The model assumes that transactions arrive at the database according to a Poisson process, that every transaction uses an equal number of

  16. The response-time distribution in a real-time database with optimistic concurrency control and exponential execution times

    NARCIS (Netherlands)

    Sassen, S.A.E.; Wal, van der J.

    1997-01-01

    For a real-time shared-memory database with optimistic concurrency control, an approximation for the transaction response-time distribution is obtained. The model assumes that transactions arrive at the database according to a Poisson process, that every transaction takes an exponential execution

  17. Evaluation of a Connectionless NoC for a Real-Time Distributed Shared Memory Many-Core System

    NARCIS (Netherlands)

    Rutgers, J.H.; Bekooij, Marco Jan Gerrit; Smit, Gerardus Johannes Maria

    2012-01-01

    Real-time embedded systems like smartphones tend to comprise an ever increasing number of processing cores. For scalability and the need for guaranteed performance, the use of a connection-oriented network-on-chip (NoC) is advocated. Furthermore, a distributed shared memory architecture is preferred

  18. Transient analysis of a grid connected wind driven induction generator using a real-time simulation platform

    Energy Technology Data Exchange (ETDEWEB)

    Ouhrouche, Mohand [Department of Applied Sciences, University of Quebec at Chicoutimi, Quebec, G7H2B1 (Canada)

    2009-03-15

    Due to its simple construction, ruggedness and low cost, the induction generator driven by a wind turbine and feeding power to the grid appears to be an attractive solution to the problem of growing energy demand in the context of environmental issues. This paper investigates the integration of such a system into the main utility using RT-Lab trademark (Trademark of Opal-RT Technologies) software package running on a simple off-the-shelf PC. This real-time simulation platform is now adopted by many high-tech industries as a real-time laboratory package for rapid control prototyping and for Hardware-in-the-Loop applications. Real-time digital simulation results obtained during contingencies, such as islanding and unbalanced faults are presented and analysed. (author)

  19. Real-Time Multifault Rush Repairing Strategy Based on Utility Theory and Multiagent System in Distribution Networks

    Directory of Open Access Journals (Sweden)

    Zhao Hao

    2016-01-01

    Full Text Available The problem of multifault rush repair in distribution networks (DNs is a multiobjective dynamic combinatorial problem with topology constraints. The problem consists of archiving an optimal faults’ allocation strategy to squads and an admissible multifault rush repairing strategy with coordinating switch operations. In this article, the utility theory is introduced to solve the first problem and a new discrete bacterial colony chemotaxis (DBCC algorithm is proposed for the second problem to determine the optimal sequence for each squad to repair faults and the corresponding switch operations. The above solution is called the two-stage approach. Additionally, a double mathematical optimization model based on the fault level is proposed in the second stage to minimize the outage loss and total repairing time. The real-time adjustment multiagent system (RA-MAS is proposed to provide facility to achieve online multifault rush repairing strategy in DNs when there are emergencies after natural disasters. The two-stage approach is illustrated with an example from a real urban distribution network and the simulation results show the effectiveness of the two-stage approach.

  20. Simulation and real-time analysis of pulse shapes from segmented HPGe-detectors

    Energy Technology Data Exchange (ETDEWEB)

    Schlarb, Michael Christian

    2009-11-17

    The capabilities of future HPGe arrays consisting of highly segmented detectors, like AGATA will depend heavily on the performance of {gamma}-ray tracking. The most crucial component in the whole concept is the pulse shape analysis (PSA). The working principle of PSA is to compare the experimental signal shape with signals available from a basis set with known interaction locations. The efficiency of the tracking algorithm hinges on the ability of the PSA to reconstruct the interaction locations accurately, especially for multiple {gamma}-interactions. Given the size of the arrays the PSA algorithm must be run in a real-time environment. A prerequisite to a successful PSA is an accurate knowledge of the detectors response. Making a full coincidence scan of a single AGATA detector, however takes between two and three months, which is too long to produce an experimental signal basis for all detector elements. A straight forward possibility is to use a precise simulation of the detector and to provide a basis of simulated signals. For this purpose the Java Agata Signal Simulation (JASS) was developed in the course of this thesis. The geometry of the detector is given with numerical precision and models describing the anisotropic mobilities of the charge carriers in germanium were taken from the literature. The pulse shapes of the transient and net-charge signals are calculated using weighting potentials on a finite grid. Special care was taken that the interpolation routine not only reproduces the weighting potentials precisely in the highly varying areas of the segment boundaries but also that its performance is independent of the location within the detector. Finally data from a coincidence scan and a pencil beam experiment were used to verify JASS. The experimental signals are reproduced accurately by the simulation. Pulse Shape Analysis (PSA) reconstructs the positions of the individual interactions and the corresponding energy deposits within the detector. This

  1. Simulation and real-time analysis of pulse shapes from segmented HPGe-detectors

    International Nuclear Information System (INIS)

    Schlarb, Michael Christian

    2009-01-01

    The capabilities of future HPGe arrays consisting of highly segmented detectors, like AGATA will depend heavily on the performance of γ-ray tracking. The most crucial component in the whole concept is the pulse shape analysis (PSA). The working principle of PSA is to compare the experimental signal shape with signals available from a basis set with known interaction locations. The efficiency of the tracking algorithm hinges on the ability of the PSA to reconstruct the interaction locations accurately, especially for multiple γ-interactions. Given the size of the arrays the PSA algorithm must be run in a real-time environment. A prerequisite to a successful PSA is an accurate knowledge of the detectors response. Making a full coincidence scan of a single AGATA detector, however takes between two and three months, which is too long to produce an experimental signal basis for all detector elements. A straight forward possibility is to use a precise simulation of the detector and to provide a basis of simulated signals. For this purpose the Java Agata Signal Simulation (JASS) was developed in the course of this thesis. The geometry of the detector is given with numerical precision and models describing the anisotropic mobilities of the charge carriers in germanium were taken from the literature. The pulse shapes of the transient and net-charge signals are calculated using weighting potentials on a finite grid. Special care was taken that the interpolation routine not only reproduces the weighting potentials precisely in the highly varying areas of the segment boundaries but also that its performance is independent of the location within the detector. Finally data from a coincidence scan and a pencil beam experiment were used to verify JASS. The experimental signals are reproduced accurately by the simulation. Pulse Shape Analysis (PSA) reconstructs the positions of the individual interactions and the corresponding energy deposits within the detector. This is

  2. Real-time monitoring of single-photon detectors against eavesdropping in quantum key distribution systems.

    Science.gov (United States)

    da Silva, Thiago Ferreira; Xavier, Guilherme B; Temporão, Guilherme P; von der Weid, Jean Pierre

    2012-08-13

    By employing real-time monitoring of single-photon avalanche photodiodes we demonstrate how two types of practical eavesdropping strategies, the after-gate and time-shift attacks, may be detected. Both attacks are identified with the detectors operating without any special modifications, making this proposal well suited for real-world applications. The monitoring system is based on accumulating statistics of the times between consecutive detection events, and extracting the afterpulse and overall efficiency of the detectors in real-time using mathematical models fit to the measured data. We are able to directly observe changes in the afterpulse probabilities generated from the after-gate and faint after-gate attacks, as well as different timing signatures in the time-shift attack. We also discuss the applicability of our scheme to other general blinding attacks.

  3. A real-time data-acquisition and analysis system with distributed UNIX workstations

    International Nuclear Information System (INIS)

    Yamashita, H.; Miyamoto, K.; Maruyama, K.; Hirosawa, H.; Nakayoshi, K.; Emura, T.; Sumi, Y.

    1996-01-01

    A compact data-acquisition system using three RISC/UNIX TM workstations (SUN TM /SPARCstation TM ) with real-time capabilities of monitoring and analysis has been developed for the study of photonuclear reactions with the large-acceptance spectrometer TAGX. One workstation acquires data from memory modules in the front-end electronics (CAMAC and TKO) with a maximum speed of 300 Kbytes/s, where data size times instantaneous rate is 1 Kbyte x 300 Hz. Another workstation, which has real-time capability for run monitoring, gets the data with a buffer manager called NOVA. The third workstation analyzes the data and reconstructs the event. In addition to a general hardware and software description, priority settings and run control by shell scripts are described. This system has recently been used successfully in a two month long experiment. (orig.)

  4. Performance results of cooperating expert systems in a distributed real-time monitoring system

    Science.gov (United States)

    Schwuttke, U. M.; Veregge, J. R.; Quan, A. G.

    1994-01-01

    There are numerous definitions for real-time systems, the most stringent of which involve guaranteeing correct system response within a domain-dependent or situationally defined period of time. For applications such as diagnosis, in which the time required to produce a solution can be non-deterministic, this requirement poses a unique set of challenges in dynamic modification of solution strategy that conforms with maximum possible latencies. However, another definition of real time is relevant in the case of monitoring systems where failure to supply a response in the proper (and often infinitesimal) amount of time allowed does not make the solution less useful (or, in the extreme example of a monitoring system responsible for detecting and deflecting enemy missiles, completely irrelevant). This more casual definition involves responding to data at the same rate at which it is produced, and is more appropriate for monitoring applications with softer real-time constraints, such as interplanetary exploration, which results in massive quantities of data transmitted at the speed of light for a number of hours before it even reaches the monitoring system. The latter definition of real time has been applied to the MARVEL system for automated monitoring and diagnosis of spacecraft telemetry. An early version of this system has been in continuous operational use since it was first deployed in 1989 for the Voyager encounter with Neptune. This system remained under incremental development until 1991 and has been under routine maintenance in operations since then, while continuing to serve as an artificial intelligence (AI) testbed in the laboratory. The system architecture has been designed to facilitate concurrent and cooperative processing by multiple diagnostic expert systems in a hierarchical organization. The diagnostic modules adhere to concepts of data-driven reasoning, constrained but complete nonoverlapping domains, metaknowledge of global consequences of anomalous

  5. Modelling, Simulation, Animation, and Real-Time Control (Mosart) for a Class of Electromechanical Systems: A System-Theoretic Approach

    Science.gov (United States)

    Rodriguez, Armando A.; Metzger, Richard P.; Cifdaloz, Oguzhan; Dhirasakdanon, Thanate; Welfert, Bruno

    2004-01-01

    This paper describes an interactive modelling, simulation, animation, and real-time control (MoSART) environment for a class of 'cart-pendulum' electromechanical systems that may be used to enhance learning within differential equations and linear algebra classes. The environment is useful for conveying fundamental mathematical/systems concepts…

  6. Study on Real-Time Simulation Analysis and Inverse Analysis System for Temperature and Stress of Concrete Dam

    Directory of Open Access Journals (Sweden)

    Lei Zhang

    2015-01-01

    Full Text Available In the concrete dam construction, it is very necessary to strengthen the real-time monitoring and scientific management of concrete temperature control. This paper constructs the analysis and inverse analysis system of temperature stress simulation, which is based on various useful data collected in real time in the process of concrete construction. The system can produce automatically data file of temperature and stress calculation and then achieve the remote real-time simulation calculation of temperature stress by using high performance computing techniques, so the inverse analysis can be carried out based on a basis of monitoring data in the database; it fulfills the automatic feedback calculation according to the error requirement and generates the corresponding curve and chart after the automatic processing and analysis of corresponding results. The system realizes the automation and intellectualization of complex data analysis and preparation work in simulation process and complex data adjustment in the inverse analysis process, which can facilitate the real-time tracking simulation and feedback analysis of concrete temperature stress in construction process and enable you to discover problems timely, take measures timely, and adjust construction scheme and can well instruct you how to ensure project quality.

  7. A Mixed Model for Real-Time, Interactive Simulation of a Cable Passing Through Several Pulleys

    International Nuclear Information System (INIS)

    Garcia-Fernandez, Ignacio; Pla-Castells, Marta; Martinez-Dura, Rafael J.

    2007-01-01

    A model of a cable and pulleys is presented that can be used in Real Time Computer Graphics applications. The model is formulated by the coupling of a damped spring and a variable coefficient wave equation, and can be integrated in more complex mechanical models of lift systems, such as cranes, elevators, etc. with a high degree of interactivity

  8. A Mixed Model for Real-Time, Interactive Simulation of a Cable Passing Through Several Pulleys

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Fernandez, Ignacio; Pla-Castells, Marta; Martinez-Dura, Rafael J [Instituto de Robotica. Universidad de Valencia (Spain)

    2007-09-06

    A model of a cable and pulleys is presented that can be used in Real Time Computer Graphics applications. The model is formulated by the coupling of a damped spring and a variable coefficient wave equation, and can be integrated in more complex mechanical models of lift systems, such as cranes, elevators, etc. with a high degree of interactivity.

  9. Towards Real-Time, Nonintrusive Estimation of Driver Workload: A Simulator Study

    NARCIS (Netherlands)

    van Gent, P.; Farah, H.; Nes, Nicole Van; van Arem, B.

    2017-01-01

    The aim of this research is to work towards building an open-source, platform-independent algorithm capable of predicting driver workload in real-time and in a non-intrusive way. To work towards a system that can also be implemented in on-road settings, we aimed at using off-the-shelf, non-intrusive

  10. Development of a High Resolution, Real Time, Distribution-Level Metering System and Associated Visualization, Modeling, and Data Analysis Functions

    Energy Technology Data Exchange (ETDEWEB)

    Bank, J.; Hambrick, J.

    2013-05-01

    NREL is developing measurement devices and a supporting data collection network specifically targeted at electrical distribution systems to support research in this area. This paper describes the measurement network which is designed to apply real-time and high speed (sub-second) measurement principles to distribution systems that are already common for the transmission level in the form of phasor measurement units and related technologies.

  11. Full integrated system of real-time monitoring based on distributed architecture for the high temperature engineering test reactor (HTTR)

    International Nuclear Information System (INIS)

    Subekti, Muhammad; Ohno, Tomio; Kudo, Kazuhiko; Takamatsu, Kuniyoshi; Nabeshima, Kunihiko

    2005-01-01

    A new monitoring system scheme based on distributed architecture for the High Temperature Engineering Test Reactor (HTTR) is proposed to assure consistency of the real-time process of expanded system. A distributed monitoring task on client PCs as an alternative architecture maximizes the throughput and capabilities of the system even if the monitoring tasks suffer a shortage of bandwidth. The prototype of the on-line monitoring system has been developed successfully and will be tested at the actual HTTR site. (author)

  12. The sign problem in real-time path integral simulations: Using the cumulant action to implement multilevel blocking

    International Nuclear Information System (INIS)

    Mak, C. H.

    2009-01-01

    A practical method to tackle the sign problem in real-time path integral simulations is proposed based on the multilevel blocking idea. The formulation is made possible by using a cumulant expansion of the action, which in addition to addressing the sign problem, provides an unbiased estimator for the action from a statistically noisy sample of real-time paths. The cumulant formulation also allows the analytical gradients of the action to be computed with little extra computational effort, and it can easily be implemented in a massively parallel environment.

  13. Implementation of real-time energy management strategy based on reinforcement learning for hybrid electric vehicles and simulation validation.

    Directory of Open Access Journals (Sweden)

    Zehui Kong

    Full Text Available To further improve the fuel economy of series hybrid electric tracked vehicles, a reinforcement learning (RL-based real-time energy management strategy is developed in this paper. In order to utilize the statistical characteristics of online driving schedule effectively, a recursive algorithm for the transition probability matrix (TPM of power-request is derived. The reinforcement learning (RL is applied to calculate and update the control policy at regular time, adapting to the varying driving conditions. A facing-forward powertrain model is built in detail, including the engine-generator model, battery model and vehicle dynamical model. The robustness and adaptability of real-time energy management strategy are validated through the comparison with the stationary control strategy based on initial transition probability matrix (TPM generated from a long naturalistic driving cycle in the simulation. Results indicate that proposed method has better fuel economy than stationary one and is more effective in real-time control.

  14. Implementation of real-time energy management strategy based on reinforcement learning for hybrid electric vehicles and simulation validation.

    Science.gov (United States)

    Kong, Zehui; Zou, Yuan; Liu, Teng

    2017-01-01

    To further improve the fuel economy of series hybrid electric tracked vehicles, a reinforcement learning (RL)-based real-time energy management strategy is developed in this paper. In order to utilize the statistical characteristics of online driving schedule effectively, a recursive algorithm for the transition probability matrix (TPM) of power-request is derived. The reinforcement learning (RL) is applied to calculate and update the control policy at regular time, adapting to the varying driving conditions. A facing-forward powertrain model is built in detail, including the engine-generator model, battery model and vehicle dynamical model. The robustness and adaptability of real-time energy management strategy are validated through the comparison with the stationary control strategy based on initial transition probability matrix (TPM) generated from a long naturalistic driving cycle in the simulation. Results indicate that proposed method has better fuel economy than stationary one and is more effective in real-time control.

  15. Simulation and real-time replacement of missing plasma signals for disruption prediction: an implementation with APODIS

    International Nuclear Information System (INIS)

    Rattá, G A; Vega, J; Murari, A

    2014-01-01

    So far, the best results for real-time disruption prediction on the Joint European Torus (JET) have been achieved with the Advanced Predictor of Disruptions (APODIS). APODIS is a data-driven system whose latest version has been implemented in JET's real time-data network. It has been designed for the real-time analysis of features (mean and frequency values) corresponding to seven plasma signals in order to foresee upcoming disruptions. In this article, non-linear regression techniques are applied to create (off-line) signal models. The models are able to generate (in real-time) ‘synthetic’ signals. Therefore, these ‘synthetic’ signals can be used to replace the original ones in cases where they are in error or missing. APODIS has been tested under these conditions, emulating real-time operation. The simulation results demonstrate that once a signal in error is replaced by the generated ‘synthetic’ one, APODIS performance is considerably improved. The development of the regression models and the implications of the results are detailed and discussed in this paper. (paper)

  16. Demo: Distributed Real-Time Generative 3D Hand Tracking using Edge GPGPU Acceleration

    DEFF Research Database (Denmark)

    Qammaz, Ammar; Kosta, Sokol; Kyriazis, Nikolaos

    2018-01-01

    computations locally. The network connection takes the place of a GPGPU accelerator and sharing resources with a larger workstation becomes the acceleration mechanism. The unique properties of a generative optimizer are examined and constitute a challenging use-case, since the requirement for real......This work demonstrates a real-time 3D hand tracking application that runs via computation offloading. The proposed framework enables the application to run on low-end mobile devices such as laptops and tablets, despite the fact that they lack the sufficient hardware to perform the required...

  17. Development of a cross-section methodology and a real-time core model for VVER-1000 simulator application

    Energy Technology Data Exchange (ETDEWEB)

    Georgieva, Emiliya Lyudmilova

    2016-06-06

    The novel academic contributions are summarized as follows. A) A cross-section modelling methodology and a cycle-specific cross-section update procedure are developed to meet fidelity requirements applicable to a cycle-specific reactor core simulation, as well as particular customer needs and practices supporting VVER-1000 operation and safety. B) A real-time version of the Nodal Expansion Method code is developed and implemented into Kozloduy 6 full-scope replica control room simulator.

  18. Toward real-time Monte Carlo simulation using a commercial cloud computing infrastructure

    International Nuclear Information System (INIS)

    Wang, Henry; Ma Yunzhi; Pratx, Guillem; Xing Lei

    2011-01-01

    Monte Carlo (MC) methods are the gold standard for modeling photon and electron transport in a heterogeneous medium; however, their computational cost prohibits their routine use in the clinic. Cloud computing, wherein computing resources are allocated on-demand from a third party, is a new approach for high performance computing and is implemented to perform ultra-fast MC calculation in radiation therapy. We deployed the EGS5 MC package in a commercial cloud environment. Launched from a single local computer with Internet access, a Python script allocates a remote virtual cluster. A handshaking protocol designates master and worker nodes. The EGS5 binaries and the simulation data are initially loaded onto the master node. The simulation is then distributed among independent worker nodes via the message passing interface, and the results aggregated on the local computer for display and data analysis. The described approach is evaluated for pencil beams and broad beams of high-energy electrons and photons. The output of cloud-based MC simulation is identical to that produced by single-threaded implementation. For 1 million electrons, a simulation that takes 2.58 h on a local computer can be executed in 3.3 min on the cloud with 100 nodes, a 47x speed-up. Simulation time scales inversely with the number of parallel nodes. The parallelization overhead is also negligible for large simulations. Cloud computing represents one of the most important recent advances in supercomputing technology and provides a promising platform for substantially improved MC simulation. In addition to the significant speed up, cloud computing builds a layer of abstraction for high performance parallel computing, which may change the way dose calculations are performed and radiation treatment plans are completed. (note)

  19. Toward real-time Monte Carlo simulation using a commercial cloud computing infrastructure

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Henry [Department of Electrical Engineering, Stanford University, Stanford, CA 94305 (United States); Ma Yunzhi; Pratx, Guillem; Xing Lei, E-mail: hwang41@stanford.edu [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA 94305-5847 (United States)

    2011-09-07

    Monte Carlo (MC) methods are the gold standard for modeling photon and electron transport in a heterogeneous medium; however, their computational cost prohibits their routine use in the clinic. Cloud computing, wherein computing resources are allocated on-demand from a third party, is a new approach for high performance computing and is implemented to perform ultra-fast MC calculation in radiation therapy. We deployed the EGS5 MC package in a commercial cloud environment. Launched from a single local computer with Internet access, a Python script allocates a remote virtual cluster. A handshaking protocol designates master and worker nodes. The EGS5 binaries and the simulation data are initially loaded onto the master node. The simulation is then distributed among independent worker nodes via the message passing interface, and the results aggregated on the local computer for display and data analysis. The described approach is evaluated for pencil beams and broad beams of high-energy electrons and photons. The output of cloud-based MC simulation is identical to that produced by single-threaded implementation. For 1 million electrons, a simulation that takes 2.58 h on a local computer can be executed in 3.3 min on the cloud with 100 nodes, a 47x speed-up. Simulation time scales inversely with the number of parallel nodes. The parallelization overhead is also negligible for large simulations. Cloud computing represents one of the most important recent advances in supercomputing technology and provides a promising platform for substantially improved MC simulation. In addition to the significant speed up, cloud computing builds a layer of abstraction for high performance parallel computing, which may change the way dose calculations are performed and radiation treatment plans are completed. (note)

  20. Toward real-time Monte Carlo simulation using a commercial cloud computing infrastructure.

    Science.gov (United States)

    Wang, Henry; Ma, Yunzhi; Pratx, Guillem; Xing, Lei

    2011-09-07

    Monte Carlo (MC) methods are the gold standard for modeling photon and electron transport in a heterogeneous medium; however, their computational cost prohibits their routine use in the clinic. Cloud computing, wherein computing resources are allocated on-demand from a third party, is a new approach for high performance computing and is implemented to perform ultra-fast MC calculation in radiation therapy. We deployed the EGS5 MC package in a commercial cloud environment. Launched from a single local computer with Internet access, a Python script allocates a remote virtual cluster. A handshaking protocol designates master and worker nodes. The EGS5 binaries and the simulation data are initially loaded onto the master node. The simulation is then distributed among independent worker nodes via the message passing interface, and the results aggregated on the local computer for display and data analysis. The described approach is evaluated for pencil beams and broad beams of high-energy electrons and photons. The output of cloud-based MC simulation is identical to that produced by single-threaded implementation. For 1 million electrons, a simulation that takes 2.58 h on a local computer can be executed in 3.3 min on the cloud with 100 nodes, a 47× speed-up. Simulation time scales inversely with the number of parallel nodes. The parallelization overhead is also negligible for large simulations. Cloud computing represents one of the most important recent advances in supercomputing technology and provides a promising platform for substantially improved MC simulation. In addition to the significant speed up, cloud computing builds a layer of abstraction for high performance parallel computing, which may change the way dose calculations are performed and radiation treatment plans are completed.

  1. Real-Time Vehicle Energy Management System Based on Optimized Distribution of Electrical Load Power

    Directory of Open Access Journals (Sweden)

    Yuefei Wang

    2016-10-01

    Full Text Available As a result of severe environmental pressure and stringent government regulations, refined energy management for vehicles has become inevitable. To improve vehicle fuel economy, this paper presents a bus-based energy management system for the electrical system of internal combustion engine vehicles. Both the model of an intelligent alternator and the model of a lead-acid battery are discussed. According to these models, the energy management for a vehicular electrical system is formulated as a global optimal control problem which aims to minimize fuel consumption. Pontryagin’s minimum principle is applied to solve the optimal control problem to realize a real-time control strategy for electrical energy management in vehicles. The control strategy can change the output of the intelligent alternator and the battery with the changes of electrical load and driving conditions in real-time. Experimental results demonstrate that, compared to the traditional open-loop control strategy, the proposed control strategy for vehicle energy management can effectively reduce fuel consumption and the fuel consumption per 100 km is decreased by approximately 1.7%.

  2. Practical Testing and Performance Analysis of Phasor Measurement Unit Using Real Time Digital Simulator (RTDS)

    DEFF Research Database (Denmark)

    Liu, Leo; Rather, Zakir Hussain; Stearn, Nathen

    2012-01-01

    Wide Area Measurement Systems (WAMS) and Wide Area Monitoring, Protection and Control Systems (WAMPACS) have evolved rapidly over the last two decades [1]. This fast emerging technology enables real time synchronized monitoring of power systems. Presently, WAMS are mainly used for real time...... visualisation and post event analysis of power systems. It is expected however, that through integration with traditional Supervisory Control and Data Acquisition (SCADA) systems, closed loop control applications will be possible. Phasor Measurement Units (PMUs) are fundamental components of WAMS. Large WAMS...... proposed to realize highly precise phasoreasurements. Further a comparative study based on features of PMUs from different major manufacturers is presented. The selection of optimal parameters, such as phasor format and filter length is also discussed for various applications....

  3. Acquisition of Real Time Simulator for Intelligent Power Networks in Operational Energy Applications

    Science.gov (United States)

    2017-12-05

    and fixed power installations to enhance DoD mission effectiveness. The long term goal of this effort is to create a strong research and education ...effort is to create a strong research and education center at UTSA focused on innovative technologies and solutions for Energy-Systems Management...in Real-Time. , Grid Low voltage dc = ~ Dual Active Bridge (DAB) With 3-Level NPC HV bridge and High frequency transformer High voltage dc

  4. COMDES-II: A Component-Based Framework for Generative Development of Distributed Real-Time Control Systems

    DEFF Research Database (Denmark)

    Ke, Xu; Sierszecki, Krzysztof; Angelov, Christo K.

    2007-01-01

    The paper presents a generative development methodology and component models of COMDES-II, a component-based software framework for distributed embedded control systems with real-time constraints. The adopted methodology allows for rapid modeling and validation of control software at a higher lev...... methodology for COMDES-II from a general perspective, describes the component models in details and demonstrates their application through a DC-Motor control system case study.......The paper presents a generative development methodology and component models of COMDES-II, a component-based software framework for distributed embedded control systems with real-time constraints. The adopted methodology allows for rapid modeling and validation of control software at a higher level...

  5. CyNC - towards a General Tool for Performance Analysis of Complex Distributed Real Time Systems

    DEFF Research Database (Denmark)

    Schiøler, Henrik; Jessen, Jan Jakob; Nielsen, Jens F. Dalsgaard

    2005-01-01

    The paper addresses the current state and the ongoing activities of a tool for performance analysis of complex real time systems. The tool named CyNC is based on network calculus allowing for the computation of backlogs and delays in a system from specified lower and upper bounds of external...... workflow and computational resources. The current version of the tool implements an extension to previous work in that it allows for general workflow and resource bounds and provides optimal solutions even to systems with cyclic dependencies. Despite the virtues of the current tool, improvements...... and extensions still remain, which are in focus of ongoing activities. Improvements include accounting for phase information to improve bounds, whereas the tool awaits extension to include flow control models, which both depend on the possibility of accounting for propagation delay. Since the current version...

  6. Distributed management system of a scanning robot programmed real time in APL language

    International Nuclear Information System (INIS)

    Liabot, M.-J.

    1980-08-01

    The aim of this work is to propose an original solution in order to implement the control operating system of a robot designed to travel between the main tank and the safety tank of the SUPERPHENIX reactor for scanning up the welding by ultrasound measurements. The system consists of: - a MITRA mini-computer programmed in APL, that manages the driving unit and defines the scanning strategy (visual unit, cheking board...). - a microprocessor that realizes the connection between the MITRA and the robot on wich the motor commands and the safety fonctions are placed. Such a solution allows to limit input output volume in the MITRA and gives the possibility to program the system in real time in APL language [fr

  7. Distribution Locational Real-Time Pricing Based Smart Building Control and Management

    Energy Technology Data Exchange (ETDEWEB)

    Hao, Jun; Dai, Xiaoxiao; Zhang, Yingchen; Zhang, Jun; Gao, Wenzhong

    2016-11-21

    This paper proposes an real-virtual parallel computing scheme for smart building operations aiming at augmenting overall social welfare. The University of Denver's campus power grid and Ritchie fitness center is used for demonstrating the proposed approach. An artificial virtual system is built in parallel to the real physical system to evaluate the overall social cost of the building operation based on the social science based working productivity model, numerical experiment based building energy consumption model and the power system based real-time pricing mechanism. Through interactive feedback exchanged between the real and virtual system, enlarged social welfare, including monetary cost reduction and energy saving, as well as working productivity improvements, can be achieved.

  8. Adaptation of the MAST passive current simulation model for real-time plasma control

    International Nuclear Information System (INIS)

    McArdle, G.J.; Taylor, D.

    2008-01-01

    Successful equilibrium reconstruction on MAST depends on a reliable estimate of the passive current induced in the thick vacuum vessel (which also acts as the load assembly) and other toroidally continuous internal support structures. For the EFIT reconstruction code, a pre-processing program takes the measured plasma and PF coil current evolution and uses a sectional model of the passive structure to solve the ODEs for electromagnetic induction. The results are written to a file, which is treated by EFIT as a set of virtual measurements of the passive current in each section. However, when a real-time version of EFIT was recently installed in the MAST plasma control system, a similar function was required for real-time estimation of the instantaneous passive current. This required several adaptation steps for the induction model to reduce the computational overhead to the absolute minimum, whilst preserving accuracy of the result. These include: ·conversion of the ODE to use an auxiliary variable, avoiding the need to calculate the time derivative of current; ·minimise the order of the system via model reduction techniques with a state-space representation of the problem; ·transformation to eigenmode form, to diagonalise the main matrix for faster computation; ·discretisation of the ODE; ·hand-optimisation to use vector instruction extensions in the real-time processor; ·splitting the task into two parts: the time-critical feedback part, and the next cycle pre-calculation part. After these optimisations, the algorithm was successfully implemented at a cost of just 65 μs per 500 μs control cycle, with only 27 μs added to the control latency. The results show good agreement with the original off-line version. Some of these optimisations have also been used subsequently to improve the performance of the off-line version

  9. Parallel real-time visualization system for large-scale simulation. Application to WSPEEDI

    International Nuclear Information System (INIS)

    Muramatsu, Kazuhiro; Otani, Takayuki; Kitabata, Hideyuki; Matsumoto, Hideki; Takei, Toshifumi; Doi, Shun

    2000-01-01

    The real-time visualization system, PATRAS (PArallel TRAcking Steering system) has been developed on parallel computing servers. The system performs almost all of the visualization tasks on a parallel computing server, and uses image data compression technique for efficient communication between the server and the client terminal. Therefore, the system realizes high performance concurrent visualization in an internet computing environment. The experience in applying PATRAS to WSPEEDI (Worldwide version of System for Prediction Environmental Emergency Dose Information) is reported. The application of PATRAS to WSPEEDI enables users to understand behaviours of radioactive tracers from different release points easily and quickly. (author)

  10. D-MSR: A Distributed Network Management Scheme for Real-Time Monitoring and Process Control Applications in Wireless Industrial Automation

    Science.gov (United States)

    Zand, Pouria; Dilo, Arta; Havinga, Paul

    2013-01-01

    Current wireless technologies for industrial applications, such as WirelessHART and ISA100.11a, use a centralized management approach where a central network manager handles the requirements of the static network. However, such a centralized approach has several drawbacks. For example, it cannot cope with dynamicity/disturbance in large-scale networks in a real-time manner and it incurs a high communication overhead and latency for exchanging management traffic. In this paper, we therefore propose a distributed network management scheme, D-MSR. It enables the network devices to join the network, schedule their communications, establish end-to-end connections by reserving the communication resources for addressing real-time requirements, and cope with network dynamicity (e.g., node/edge failures) in a distributed manner. According to our knowledge, this is the first distributed management scheme based on IEEE 802.15.4e standard, which guides the nodes in different phases from joining until publishing their sensor data in the network. We demonstrate via simulation that D-MSR can address real-time and reliable communication as well as the high throughput requirements of industrial automation wireless networks, while also achieving higher efficiency in network management than WirelessHART, in terms of delay and overhead. PMID:23807687

  11. D-MSR: a distributed network management scheme for real-time monitoring and process control applications in wireless industrial automation.

    Science.gov (United States)

    Zand, Pouria; Dilo, Arta; Havinga, Paul

    2013-06-27

    Current wireless technologies for industrial applications, such as WirelessHART and ISA100.11a, use a centralized management approach where a central network manager handles the requirements of the static network. However, such a centralized approach has several drawbacks. For example, it cannot cope with dynamicity/disturbance in large-scale networks in a real-time manner and it incurs a high communication overhead and latency for exchanging management traffic. In this paper, we therefore propose a distributed network management scheme, D-MSR. It enables the network devices to join the network, schedule their communications, establish end-to-end connections by reserving the communication resources for addressing real-time requirements, and cope with network dynamicity (e.g., node/edge failures) in a distributed manner. According to our knowledge, this is the first distributed management scheme based on IEEE 802.15.4e standard, which guides the nodes in different phases from joining until publishing their sensor data in the network. We demonstrate via simulation that D-MSR can address real-time and reliable communication as well as the high throughput requirements of industrial automation wireless networks, while also achieving higher efficiency in network management than WirelessHART, in terms of delay and overhead.

  12. PROCESSING, CATALOGUING AND DISTRIBUTION OF UAS IMAGES IN NEAR REAL TIME

    Directory of Open Access Journals (Sweden)

    I. Runkel

    2013-08-01

    demands – the images can be checked and interpreted in near real-time. For sensible areas it gives you the possibility to inform remote decision makers or interpretation experts in order to provide them situations awareness, wherever they are. For monitoring and inspection tasks it speeds up the process of data capture and data interpretation. The fully automated workflow of data pre-processing, data georeferencing, data cataloguing and data dissemination in near real time was developed based on the Intergraph products ERDAS IMAGINE, ERDAS APOLLO and GEOSYSTEMS METAmorph!IT. It is offered as adaptable solution by GEOSYSTEMS GmbH.

  13. Processing, Cataloguing and Distribution of Uas Images in Near Real Time

    Science.gov (United States)

    Runkel, I.

    2013-08-01

    can be checked and interpreted in near real-time. For sensible areas it gives you the possibility to inform remote decision makers or interpretation experts in order to provide them situations awareness, wherever they are. For monitoring and inspection tasks it speeds up the process of data capture and data interpretation. The fully automated workflow of data pre-processing, data georeferencing, data cataloguing and data dissemination in near real time was developed based on the Intergraph products ERDAS IMAGINE, ERDAS APOLLO and GEOSYSTEMS METAmorph!IT. It is offered as adaptable solution by GEOSYSTEMS GmbH.

  14. Simulated real-time process monitoring of a molten salt electrorefiner

    International Nuclear Information System (INIS)

    Rappleye, Devin; Simpson, Michael; Cumberland, Riley; McNelis, David; Yim, Man-Sung

    2014-01-01

    Highlights: • An alternative approach to safeguarding and monitoring pyroprocessing is proposed. • Possible signals to be used to monitor an electrorefiner are identified. • An inverse model was developed to determine deposition rates at the cathode. • The sensitivity of certain parameters in the inverse model are presented. - Abstract: An alternative approach to monitoring the pyrochemical process (pyroprocessing) for spent nuclear fuel treatment is proposed and examined. This approach relies on modeling and the real-time analysis of process readings. Using an electrorefiner model, named ERAD, cathode potential and cell current were identified as useful process readings. To provide a real-time analysis of these two process readings, an inverse model was developed based on fundamental electrochemical relations. The model was applied to the following operating modes: pure uranium deposition, co-deposition of uranium and plutonium, and co-deposition of uranium and zirconium. Using the cell current and cathode potential, the model predicted which species were depositing and their rates. The deposition rates predicted by the inverse model compared favorably to those calculated by ERAD

  15. Distributed Multi-Sensor Real-Time Building Environmental Parameters Monitoring System with Remote Data Access

    Directory of Open Access Journals (Sweden)

    Beinarts Ivars

    2014-12-01

    Full Text Available In this paper the advanced monitoring system of multiple environmental parameters is presented. The purpose of the system is a long-term estimation of energy efficiency and sustainability for the research test stands which are made of different building materials. Construction of test stands, and placement of main sensors are presented in the first chapter. The structure of data acquisition system includes a real-time interface with sensors and a data logger that allows to acquire and log data from all sensors with fixed rate. The data logging system provides a remote access to the processing of the acquired data and carries out periodical saving at a remote FTP server using an Internet connection. The system architecture and the usage of sensors are explained in the second chapter. In the third chapter implementation of the system, different interfaces of sensors and energy measuring devices are discussed and several examples of data logger program are presented. Each data logger is reading data from analog and digital channels. Measurements can be displayed directly on a screen using WEB access or using data from FTP server. Measurements and acquired data graphical results are presented in the fourth chapter in the selected diagrams. The benefits of the developed system are presented in the conclusion.

  16. Surveying multidisciplinary aspects in real-time distributed coding for Wireless Sensor Networks.

    Science.gov (United States)

    Braccini, Carlo; Davoli, Franco; Marchese, Mario; Mongelli, Maurizio

    2015-01-27

    Wireless Sensor Networks (WSNs), where a multiplicity of sensors observe a physical phenomenon and transmit their measurements to one or more sinks, pertain to the class of multi-terminal source and channel coding problems of Information Theory. In this category, "real-time" coding is often encountered for WSNs, referring to the problem of finding the minimum distortion (according to a given measure), under transmission power constraints, attainable by encoding and decoding functions, with stringent limits on delay and complexity. On the other hand, the Decision Theory approach seeks to determine the optimal coding/decoding strategies or some of their structural properties. Since encoder(s) and decoder(s) possess different information, though sharing a common goal, the setting here is that of Team Decision Theory. A more pragmatic vision rooted in Signal Processing consists of fixing the form of the coding strategies (e.g., to linear functions) and, consequently, finding the corresponding optimal decoding strategies and the achievable distortion, generally by applying parametric optimization techniques. All approaches have a long history of past investigations and recent results. The goal of the present paper is to provide the taxonomy of the various formulations, a survey of the vast related literature, examples from the authors' own research, and some highlights on the inter-play of the different theories.

  17. Development and Field Test of a Real-Time Database in the Korean Smart Distribution Management System

    Directory of Open Access Journals (Sweden)

    Sang-Yun Yun

    2014-03-01

    Full Text Available Recently, a distribution management system (DMS that can conduct periodical system analysis and control by mounting various applications programs has been actively developed. In this paper, we summarize the development and demonstration of a database structure that can perform real-time system analysis and control of the Korean smart distribution management system (KSDMS. The developed database structure consists of a common information model (CIM-based off-line database (DB, a physical DB (PDB for DB establishment of the operating server, a real-time DB (RTDB for real-time server operation and remote terminal unit data interconnection, and an application common model (ACM DB for running application programs. The ACM DB for real-time system analysis and control of the application programs was developed by using a parallel table structure and a link list model, thereby providing fast input and output as well as high execution speed of application programs. Furthermore, the ACM DB was configured with hierarchical and non-hierarchical data models to reflect the system models that increase the DB size and operation speed through the reduction of the system, of which elements were unnecessary for analysis and control. The proposed database model was implemented and tested at the Gochaing and Jeju offices using a real system. Through data measurement of the remote terminal units, and through the operation and control of the application programs using the measurement, the performance, speed, and integrity of the proposed database model were validated, thereby demonstrating that this model can be applied to real systems.

  18. POD for Real-Time Simulation of Hyperelastic Soft Biological Tissue Using the Point Collocation Method of Finite Spheres

    Directory of Open Access Journals (Sweden)

    Suleiman Banihani

    2013-01-01

    Full Text Available The point collocation method of finite spheres (PCMFS is used to model the hyperelastic response of soft biological tissue in real time within the framework of virtual surgery simulation. The proper orthogonal decomposition (POD model order reduction (MOR technique was used to achieve reduced-order model of the problem, minimizing computational cost. The PCMFS is a physics-based meshfree numerical technique for real-time simulation of surgical procedures where the approximation functions are applied directly on the strong form of the boundary value problem without the need for integration, increasing computational efficiency. Since computational speed has a significant role in simulation of surgical procedures, the proposed technique was able to model realistic nonlinear behavior of organs in real time. Numerical results are shown to demonstrate the effectiveness of the new methodology through a comparison between full and reduced analyses for several nonlinear problems. It is shown that the proposed technique was able to achieve good agreement with the full model; moreover, the computational and data storage costs were significantly reduced.

  19. Modeling and real time simulation of an HVDC inverter feeding a weak AC system based on commutation failure study.

    Science.gov (United States)

    Mankour, Mohamed; Khiat, Mounir; Ghomri, Leila; Chaker, Abdelkader; Bessalah, Mourad

    2018-06-01

    This paper presents modeling and study of 12-pulse HVDC (High Voltage Direct Current) based on real time simulation where the HVDC inverter is connected to a weak AC system. In goal to study the dynamic performance of the HVDC link, two serious kind of disturbance are applied at HVDC converters where the first one is the single phase to ground AC fault and the second one is the DC link to ground fault. The study is based on two different mode of analysis, which the first is to test the performance of the DC control and the second is focalized to study the effect of the protection function on the system behavior. This real time simulation considers the strength of the AC system to witch is connected and his relativity with the capacity of the DC link. The results obtained are validated by means of RT-lab platform using digital Real time simulator Hypersim (OP-5600), the results carried out show the effect of the DC control and the influence of the protection function to reduce the probability of commutation failures and also for helping inverter to take out from commutation failure even while the DC control fails to eliminate them. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  20. Propulsion Powertrain Real-Time Simulation Using Hardware-in-the-Loop (HIL) for Aircraft Electric Propulsion System

    Science.gov (United States)

    Choi, Benjamin B.; Brown, Gerald V.

    2017-01-01

    It is essential to design a propulsion powertrain real-time simulator using the hardware-in-the-loop (HIL) system that emulates an electrified aircraft propulsion (EAP) systems power grid. This simulator would enable us to facilitate in-depth understanding of the system principles, to validate system model analysis and performance prediction, and to demonstrate the proof-of-concept of the EAP electrical system. This paper describes how subscale electrical machines with their controllers can mimic the power components in an EAP powertrain. In particular, three powertrain emulations are presented to mimic 1) a gas turbo-=shaft engine driving a generator, consisting of two permanent magnet (PM) motors with brushless motor drives, coupled by a shaft, 2) a motor driving a propulsive fan, and 3) a turbo-shaft engine driven fan (turbofan engine) operation. As a first step towards the demonstration, experimental dynamic characterization of the two motor drive systems, coupled by a mechanical shaft, were performed. The previously developed analytical motor models1 were then replaced with the experimental motor models to perform the real-time demonstration in the predefined flight path profiles. This technique can convert the plain motor system into a unique EAP power grid emulator that enables rapid analysis and real-time simulation performance using hardware-in-the-loop (HIL).

  1. Real-Time Distribution Feeder Performance Monitoring, Advisory Control, and Health Management System

    Energy Technology Data Exchange (ETDEWEB)

    Stoupis, James; Mousavi, Mirrasoul

    2014-09-30

    New data collection system equipment was installed in Xcel Energy substations and data was collected from 6 substations and 20 feeders. During Phase I, ABB collected and analyzed 793 real-time events to date from 6 Xcel Energy substations and continues today. The development and integration of several applications was completed during the course of this project, including a model-based faulted segment identification algorithm, with very positive results validated with field-gathered data discussed and included in this report. For mostly underground feeders, the success rate is 90% and the overreach rate is 90%. For mostly overhead feeders, the success rate is 74% and the overreach rate is 50%. The developed method is producing very accurate results for mostly underground feeders. For mostly overhead feeders, due to the bad OMS data quality and varying fault resistance when arcing, the developed method is producing good results but with much room for improvement. One area where the algorithm can be improved is the accuracy for sub-cycle fault events. In these cases, the accuracy of the conventional signal processing methods suffers due to most of these methods being based on a one-cycle processing window. By improving the signal processing accuracy, the accuracy of the faulted segment identification algorithm will also improve significantly. ABB intends to devote research in this area in the near future to help solve this problem. Other new applications developed during the course of the project include volt/VAR monitoring, unbalanced capacitor switching detection, unbalanced feeder loading detection, and feeder overloading detection. An important aspect of the demonstration phase of the project is to show the ability to provide adequate “heads-up” time ahead of customer calls or AMI reports so that the operators are provided with the much needed time to collect information needed to address an outage. The advance notification feature of the demonstration system

  2. Energy and Reserve under Distributed Energy Resources Management—Day-Ahead, Hour-Ahead and Real-Time

    Directory of Open Access Journals (Sweden)

    Tiago Soares

    2017-11-01

    Full Text Available The increasing penetration of distributed energy resources based on renewable energy sources in distribution systems leads to a more complex management of power systems. Consequently, ancillary services become even more important to maintain the system security and reliability. This paper proposes and evaluates a generic model for day-ahead, intraday (hour-ahead and real-time scheduling, considering the joint optimization of energy and reserve in the scope of the virtual power player concept. The model aims to minimize the operation costs in the point of view of one aggregator agent taking into account the balance of the distribution system. For each scheduling stage, previous scheduling results and updated forecasts are considered. An illustrative test case of a distribution network with 33 buses, considering a large penetration of distribution energy resources allows demonstrating the benefits of the proposed model.

  3. Towards real-time communication between in vivo neurophysiological data sources and simulator-based brain biomimetic models.

    Science.gov (United States)

    Lee, Giljae; Matsunaga, Andréa; Dura-Bernal, Salvador; Zhang, Wenjie; Lytton, William W; Francis, Joseph T; Fortes, José Ab

    2014-11-01

    Development of more sophisticated implantable brain-machine interface (BMI) will require both interpretation of the neurophysiological data being measured and subsequent determination of signals to be delivered back to the brain. Computational models are the heart of the machine of BMI and therefore an essential tool in both of these processes. One approach is to utilize brain biomimetic models (BMMs) to develop and instantiate these algorithms. These then must be connected as hybrid systems in order to interface the BMM with in vivo data acquisition devices and prosthetic devices. The combined system then provides a test bed for neuroprosthetic rehabilitative solutions and medical devices for the repair and enhancement of damaged brain. We propose here a computer network-based design for this purpose, detailing its internal modules and data flows. We describe a prototype implementation of the design, enabling interaction between the Plexon Multichannel Acquisition Processor (MAP) server, a commercial tool to collect signals from microelectrodes implanted in a live subject and a BMM, a NEURON-based model of sensorimotor cortex capable of controlling a virtual arm. The prototype implementation supports an online mode for real-time simulations, as well as an offline mode for data analysis and simulations without real-time constraints, and provides binning operations to discretize continuous input to the BMM and filtering operations for dealing with noise. Evaluation demonstrated that the implementation successfully delivered monkey spiking activity to the BMM through LAN environments, respecting real-time constraints.

  4. Design and Performance Evaluation of an Adaptive Resource Management Framework for Distributed Real-Time and Embedded Systems

    Directory of Open Access Journals (Sweden)

    Chen Yingming

    2008-01-01

    Full Text Available Abstract Achieving end-to-end quality of service (QoS in distributed real-time embedded (DRE systems require QoS support and enforcement from their underlying operating platforms that integrates many real-time capabilities, such as QoS-enabled network protocols, real-time operating system scheduling mechanisms and policies, and real-time middleware services. As standards-based quality of service (QoS enabled component middleware automates integration and configuration activities, it is increasingly being used as a platform for developing open DRE systems that execute in environments where operational conditions, input workload, and resource availability cannot be characterized accurately a priori. Although QoS-enabled component middleware offers many desirable features, however, it historically lacked the ability to allocate resources efficiently and enable the system to adapt to fluctuations in input workload, resource availability, and operating conditions. This paper presents three contributions to research on adaptive resource management for component-based open DRE systems. First, we describe the structure and functionality of the resource allocation and control engine (RACE, which is an open-source adaptive resource management framework built atop standards-based QoS-enabled component middleware. Second, we demonstrate and evaluate the effectiveness of RACE in the context of a representative open DRE system: NASA's magnetospheric multiscale mission system. Third, we present an empirical evaluation of RACE's scalability as the number of nodes and applications in a DRE system grows. Our results show that RACE is a scalable adaptive resource management framework and yields a predictable and high-performance system, even in the face of changing operational conditions and input workload.

  5. Design and Performance Evaluation of an Adaptive Resource Management Framework for Distributed Real-Time and Embedded Systems

    Directory of Open Access Journals (Sweden)

    Chenyang Lu

    2008-04-01

    Full Text Available Achieving end-to-end quality of service (QoS in distributed real-time embedded (DRE systems require QoS support and enforcement from their underlying operating platforms that integrates many real-time capabilities, such as QoS-enabled network protocols, real-time operating system scheduling mechanisms and policies, and real-time middleware services. As standards-based quality of service (QoS enabled component middleware automates integration and configuration activities, it is increasingly being used as a platform for developing open DRE systems that execute in environments where operational conditions, input workload, and resource availability cannot be characterized accurately a priori. Although QoS-enabled component middleware offers many desirable features, however, it historically lacked the ability to allocate resources efficiently and enable the system to adapt to fluctuations in input workload, resource availability, and operating conditions. This paper presents three contributions to research on adaptive resource management for component-based open DRE systems. First, we describe the structure and functionality of the resource allocation and control engine (RACE, which is an open-source adaptive resource management framework built atop standards-based QoS-enabled component middleware. Second, we demonstrate and evaluate the effectiveness of RACE in the context of a representative open DRE system: NASA's magnetospheric multiscale mission system. Third, we present an empirical evaluation of RACE's scalability as the number of nodes and applications in a DRE system grows. Our results show that RACE is a scalable adaptive resource management framework and yields a predictable and high-performance system, even in the face of changing operational conditions and input workload.

  6. A Unified Framework for Verification and Complexity Analysis of Real-Time and Distributed Systems

    National Research Council Canada - National Science Library

    Lynch, Nancy

    1997-01-01

    .... These examples arise from a diverse set of application areas, including connection management protocols, clock synchronization, fault-tolerant distributed consensus, group communication, and real...

  7. Modelling, simulation and experimental verification for renewable agents connected to a distorted utility grid using a Real-Time Digital Simulation Platform

    International Nuclear Information System (INIS)

    Guerrero-Rodríguez, N.F.; Rey-Boué, Alexis B.

    2014-01-01

    Highlights: • A MSOGI-FLL is used to detect the frequency. • A PR harmonic-compensator is used. • Grid-connected PV system insensitive to harmonic pollution. • RTDS reinforced the final validation of the control algorithms. • Several algorithms are combined in this paper. - Abstract: The large number of Photovoltaic plants and its utilization as agents of a Distributed Generation Systems justified the increasing efforts towards the optimal design of the overall grid-connected System. In a Distributed Generation environment the low voltage 3-phase utility grid could be affected by some disturbances such as voltage unbalanced, variations of frequency and harmonics distortion and it is mandatory that the control algorithms used in the inverter can be able to maintain the power flow between the renewable agent and the low voltage 3-phase utility grid; in addition a unitary power factor must be attained. A Proportional-Resonant regulator is used to performance a current control with the output current of the inverter and a Multiple Second Order Generalized Integrator Frequency-Locked Loop (MSOGI-FLL) is used to detect the frequency of the low voltage 3-phase utility grid. Some low order harmonics are introduced in the low voltage 3-phase utility grid in order to see the effect of the harmonic compensator. In order to validate the model of the Photovoltaic Renewable agent, the synchronization algorithm and the inverter control algorithm, some simulations using MATLAB/SIMULINK from The MathWorks, Inc. are shown firstly, and secondly, some Real-Time Digital Simulation tests using a Real-Time Digital Simulation (RTDS) Platform are carried out

  8. Accounting for large deformations in real-time simulations of soft tissues based on reduced-order models.

    Science.gov (United States)

    Niroomandi, S; Alfaro, I; Cueto, E; Chinesta, F

    2012-01-01

    Model reduction techniques have shown to constitute a valuable tool for real-time simulation in surgical environments and other fields. However, some limitations, imposed by real-time constraints, have not yet been overcome. One of such limitations is the severe limitation in time (established in 500Hz of frequency for the resolution) that precludes the employ of Newton-like schemes for solving non-linear models as the ones usually employed for modeling biological tissues. In this work we present a technique able to deal with geometrically non-linear models, based on the employ of model reduction techniques, together with an efficient non-linear solver. Examples of the performance of the technique over some examples will be given. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  9. Man-machine interface design of real-time hardware-in-loop simulation system for power regulation of nuclear heating reactor

    International Nuclear Information System (INIS)

    Ni Xiaoli; Huang Xiaojin; Dong Zhe

    2009-01-01

    It is necessary to set up real-time hardware-in-loop simulation system for power regulation of nuclear heating reactor (NHR) because it is used in the load following instance such as seawater desalination and energy source. As the experiment data are so large that it is hard to be real-time all in one computer and to save and show the data.With the distributed configuration, the system was set up having a legible and intuitionist man-machine interface, speeding the model calculation computer and meeting the requirements of power regulation of NHR. Screen clear and concise, easy command input and results output make the system easier to verify. (authors)

  10. A heterogeneous system based on GPU and multi-core CPU for real-time fluid and rigid body simulation

    Science.gov (United States)

    da Silva Junior, José Ricardo; Gonzalez Clua, Esteban W.; Montenegro, Anselmo; Lage, Marcos; Dreux, Marcelo de Andrade; Joselli, Mark; Pagliosa, Paulo A.; Kuryla, Christine Lucille

    2012-03-01

    Computational fluid dynamics in simulation has become an important field not only for physics and engineering areas but also for simulation, computer graphics, virtual reality and even video game development. Many efficient models have been developed over the years, but when many contact interactions must be processed, most models present difficulties or cannot achieve real-time results when executed. The advent of parallel computing has enabled the development of many strategies for accelerating the simulations. Our work proposes a new system which uses some successful algorithms already proposed, as well as a data structure organisation based on a heterogeneous architecture using CPUs and GPUs, in order to process the simulation of the interaction of fluids and rigid bodies. This successfully results in a two-way interaction between them and their surrounding objects. As far as we know, this is the first work that presents a computational collaborative environment which makes use of two different paradigms of hardware architecture for this specific kind of problem. Since our method achieves real-time results, it is suitable for virtual reality, simulation and video game fluid simulation problems.

  11. Expressing Environment Assumptions and Real-time Requirements for a Distributed Embedded System with Shared Variables

    DEFF Research Database (Denmark)

    Tjell, Simon; Fernandes, João Miguel

    2008-01-01

    In a distributed embedded system, it is often necessary to share variables among its computing nodes to allow the distribution of control algorithms. It is therefore necessary to include a component in each node that provides the service of variable sharing. For that type of component, this paper...

  12. A 3D simulation look-up library for real-time airborne gamma-ray spectroscopy

    Science.gov (United States)

    Kulisek, Jonathan A.; Wittman, Richard S.; Miller, Erin A.; Kernan, Warnick J.; McCall, Jonathon D.; McConn, Ron J.; Schweppe, John E.; Seifert, Carolyn E.; Stave, Sean C.; Stewart, Trevor N.

    2018-01-01

    A three-dimensional look-up library consisting of simulated gamma-ray spectra was developed to leverage, in real-time, the abundance of data provided by a helicopter-mounted gamma-ray detection system consisting of 92 CsI-based radiation sensors and exhibiting a highly angular-dependent response. We have demonstrated how this library can be used to help effectively estimate the terrestrial gamma-ray background, develop simulated flight scenarios, and to localize radiological sources. Source localization accuracy was significantly improved, particularly for weak sources, by estimating the entire gamma-ray spectra while accounting for scattering in the air, and especially off the ground.

  13. Simulation of a Real-Time Brain Computer Interface for Detecting a Self-Paced Hitting Task.

    Science.gov (United States)

    Hammad, Sofyan H; Kamavuako, Ernest N; Farina, Dario; Jensen, Winnie

    2016-12-01

    An invasive brain-computer interface (BCI) is a promising neurorehabilitation device for severely disabled patients. Although some systems have been shown to work well in restricted laboratory settings, their utility must be tested in less controlled, real-time environments. Our objective was to investigate whether a specific motor task could be reliably detected from multiunit intracortical signals from freely moving animals in a simulated, real-time setting. Intracortical signals were first obtained from electrodes placed in the primary motor cortex of four rats that were trained to hit a retractable paddle (defined as a "Hit"). In the simulated real-time setting, the signal-to-noise-ratio was first increased by wavelet denoising. Action potentials were detected, and features were extracted (spike count, mean absolute values, entropy, and combination of these features) within pre-defined time windows (200 ms, 300 ms, and 400 ms) to classify the occurrence of a "Hit." We found higher detection accuracy of a "Hit" (73.1%, 73.4%, and 67.9% for the three window sizes, respectively) when the decision was made based on a combination of features rather than on a single feature. However, the duration of the window length was not statistically significant (p = 0.5). Our results showed the feasibility of detecting a motor task in real time in a less restricted environment compared to environments commonly applied within invasive BCI research, and they showed the feasibility of using information extracted from multiunit recordings, thereby avoiding the time-consuming and complex task of extracting and sorting single units. © 2016 International Neuromodulation Society.

  14. Design Of Real-Time Implementable Distributed Suboptimal Control: An LQR Perspective

    KAUST Repository

    Jaleel, Hassan; Shamma, Jeff S.

    2017-01-01

    of establishing a communication link between two base stations with minimum energy consumption. We show through simulations that the performance under the proposed framework is close to the optimal performance and the suboptimal policy can be efficiently

  15. Real time adjustment of slow changing flow components in distributed urban runoff models

    DEFF Research Database (Denmark)

    Borup, Morten; Grum, M.; Mikkelsen, Peter Steen

    2011-01-01

    In many urban runoff systems infiltrating water contributes with a substantial part of the total inflow and therefore most urban runoff modelling packages include hydrological models for simulating the infiltrating inflow. This paper presents a method for deterministic updating of the hydrological...... improvements for regular simulations as well as up to 10 hour forecasts. The updating method reduces the impact of non-representative precipitation estimates as well as model structural errors and leads to better overall modelling results....

  16. TH-CD-207A-08: Simulated Real-Time Image Guidance for Lung SBRT Patients Using Scatter Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Redler, G; Cifter, G; Templeton, A; Lee, C; Bernard, D; Liao, Y; Zhen, H; Turian, J; Chu, J [Rush University Medical Center, Chicago, IL (United States)

    2016-06-15

    Purpose: To develop a comprehensive Monte Carlo-based model for the acquisition of scatter images of patient anatomy in real-time, during lung SBRT treatment. Methods: During SBRT treatment, images of patient anatomy can be acquired from scattered radiation. To rigorously examine the utility of scatter images for image guidance, a model is developed using MCNP code to simulate scatter images of phantoms and lung cancer patients. The model is validated by comparing experimental and simulated images of phantoms of different complexity. The differentiation between tissue types is investigated by imaging objects of known compositions (water, lung, and bone equivalent). A lung tumor phantom, simulating materials and geometry encountered during lung SBRT treatments, is used to investigate image noise properties for various quantities of delivered radiation (monitor units(MU)). Patient scatter images are simulated using the validated simulation model. 4DCT patient data is converted to an MCNP input geometry accounting for different tissue composition and densities. Lung tumor phantom images acquired with decreasing imaging time (decreasing MU) are used to model the expected noise amplitude in patient scatter images, producing realistic simulated patient scatter images with varying temporal resolution. Results: Image intensity in simulated and experimental scatter images of tissue equivalent objects (water, lung, bone) match within the uncertainty (∼3%). Lung tumor phantom images agree as well. Specifically, tumor-to-lung contrast matches within the uncertainty. The addition of random noise approximating quantum noise in experimental images to simulated patient images shows that scatter images of lung tumors can provide images in as fast as 0.5 seconds with CNR∼2.7. Conclusions: A scatter imaging simulation model is developed and validated using experimental phantom scatter images. Following validation, lung cancer patient scatter images are simulated. These simulated

  17. TH-CD-207A-08: Simulated Real-Time Image Guidance for Lung SBRT Patients Using Scatter Imaging

    International Nuclear Information System (INIS)

    Redler, G; Cifter, G; Templeton, A; Lee, C; Bernard, D; Liao, Y; Zhen, H; Turian, J; Chu, J

    2016-01-01

    Purpose: To develop a comprehensive Monte Carlo-based model for the acquisition of scatter images of patient anatomy in real-time, during lung SBRT treatment. Methods: During SBRT treatment, images of patient anatomy can be acquired from scattered radiation. To rigorously examine the utility of scatter images for image guidance, a model is developed using MCNP code to simulate scatter images of phantoms and lung cancer patients. The model is validated by comparing experimental and simulated images of phantoms of different complexity. The differentiation between tissue types is investigated by imaging objects of known compositions (water, lung, and bone equivalent). A lung tumor phantom, simulating materials and geometry encountered during lung SBRT treatments, is used to investigate image noise properties for various quantities of delivered radiation (monitor units(MU)). Patient scatter images are simulated using the validated simulation model. 4DCT patient data is converted to an MCNP input geometry accounting for different tissue composition and densities. Lung tumor phantom images acquired with decreasing imaging time (decreasing MU) are used to model the expected noise amplitude in patient scatter images, producing realistic simulated patient scatter images with varying temporal resolution. Results: Image intensity in simulated and experimental scatter images of tissue equivalent objects (water, lung, bone) match within the uncertainty (∼3%). Lung tumor phantom images agree as well. Specifically, tumor-to-lung contrast matches within the uncertainty. The addition of random noise approximating quantum noise in experimental images to simulated patient images shows that scatter images of lung tumors can provide images in as fast as 0.5 seconds with CNR∼2.7. Conclusions: A scatter imaging simulation model is developed and validated using experimental phantom scatter images. Following validation, lung cancer patient scatter images are simulated. These simulated

  18. Scheduling and Prototyping of Distributed Real-Time Systems (An Approach Using Jini/JavaSpaces)

    National Research Council Canada - National Science Library

    Demirtas, Tolga

    2002-01-01

    .... This thesis proposes a formal model to capture these network constraints and develops proxy-based network buffer technique to support the inter-process communication for the user-defined distributed...

  19. Integration of real-time mapping technology in disaster relief distribution.

    Science.gov (United States)

    2013-02-01

    Vehicle routing for disaster relief distribution involves many challenges that distinguish this problem from those in commercial settings, given the time sensitive and resource constrained nature of relief activities. While operations research approa...

  20. Agent Based Distributed Control of Islanded Microgrid - Real-Time Cyber-Physical Implementation

    OpenAIRE

    Nguyen, Tung Lam; Tran, Quoc-Tuan; Caire, Raphael; Gavriluta, Catalin; Nguyen, Van Hoa

    2017-01-01

    In the hierarchical control of an islanded microgrid, secondary control could be centralized or distributed. The former control strategy has several disadvantages, such as single point of failure at the level of the central controller as well as high investment of communication infrastructure. In this paper a three-layer architecture of distributed control is given, including the device layer, the control layer as well as the agent layer. The agent layer is a multi-agent system in which each ...

  1. Real-time deformations of organ based on structural mechanics for surgical simulators

    Science.gov (United States)

    Nakaguchi, Toshiya; Tagaya, Masashi; Tamura, Nobuhiko; Tsumura, Norimichi; Miyake, Yoichi

    2006-03-01

    This research proposes the deformation model of organs for the development of the medical training system using Virtual Reality (VR) technology. First, the proposed model calculates the strains of coordinate axis. Secondly, the deformation is obtained by mapping the coordinate of the object to the strained coordinate. We assume the beams in the coordinate space to calculate the strain of the coordinate axis. The forces acting on the object are converted to the forces applied to the beams. The bend and the twist of the beams are calculated based on the theory of structural mechanics. The bend is derived by the finite element method. We propose two deformation methods which differ in the position of the beams in the coordinate space. One method locates the beams along the three orthogonal axes (x, y, z). Another method locates the beam in the area where the deformation is large. In addition, the strain of the coordinate axis is attenuated in proportion to the distance from the point of action to consider the attenuation of the stress which is a viscoelastic feature of the organs. The proposed model needs less computational cost compared to the conventional deformation method since our model does not need to divide the object into the elasticity element. The proposed model was implemented in the laparoscopic surgery training system, and a real-time deformation can be realized.

  2. Integrating viscoelastic mass spring dampers into position-based dynamics to simulate soft tissue deformation in real time.

    Science.gov (United States)

    Xu, Lang; Lu, Yuhua; Liu, Qian

    2018-02-01

    We propose a novel method to simulate soft tissue deformation for virtual surgery applications. The method considers the mechanical properties of soft tissue, such as its viscoelasticity, nonlinearity and incompressibility; its speed, stability and accuracy also meet the requirements for a surgery simulator. Modifying the traditional equation for mass spring dampers (MSD) introduces nonlinearity and viscoelasticity into the calculation of elastic force. Then, the elastic force is used in the constraint projection step for naturally reducing constraint potential. The node position is enforced by the combined spring force and constraint conservative force through Newton's second law. We conduct a comparison study of conventional MSD and position-based dynamics for our new integrating method. Our approach enables stable, fast and large step simulation by freely controlling visual effects based on nonlinearity, viscoelasticity and incompressibility. We implement a laparoscopic cholecystectomy simulator to demonstrate the practicality of our method, in which liver and gallbladder deformation can be simulated in real time. Our method is an appropriate choice for the development of real-time virtual surgery applications.

  3. Applicability of Agent-Based Technology for Acquisition, Monitoring and Process Control Systems at Real Time for Distributed Architectures

    International Nuclear Information System (INIS)

    Dorao, Carlos; Fontanini, H; Fernandez, R

    2000-01-01

    Modern industrial plants are characterized by their large size and higher complexity of the processes involved in their operations.The real time monitoring systems of theses plants must be used a distributed architecture.Due to the pressure of competitive markets, an efficient adaptability to changes must be present in the plants.Modifications in the plants due to changes in the lay-out, the introduction of newer supervision, control and monitoring technologies must not affect the integrity of the systems.The aim of this work is give an introduction to the agent-based technology and analyze it advantage for the development of a modern monitoring system

  4. Real-Time Procurement Strategies of a Proactive Distribution Company with Aggregator-Based Demand Response

    DEFF Research Database (Denmark)

    Zhang, Chunyu; Wang, Qi; Wang, Jianhui

    2016-01-01

    and inelastic demand components. A one-leader multi-follower bilevel model is proposed to derive the procurement strategies, i.e., the upper-level problem intends to maximize the profit of the proactive distribution company, while the lower-level expresses the profit maximization per rational aggregator....... The proposed model is then transformed into a solvable mathematical program with equilibrium constraints through a primal-dual approach. A modified 33-bus distribution network is utilized to demonstrate the effectiveness of the proposed model....

  5. Expressing Environment Assumptions and Real-time Requirements for a Distributed Embedded System with Shared Variables

    DEFF Research Database (Denmark)

    Tjell, Simon; Fernandes, João Miguel

    2008-01-01

    In a distributed embedded system, it is often necessary to share variables among its computing nodes to allow the distribution of control algorithms. It is therefore necessary to include a component in each node that provides the service of variable sharing. For that type of component, this paper...... for the component. The CPN model can be used to validate the environment assumptions and the requirements. The validation is performed by execution of the model during which traces of events and states are automatically generated and evaluated against the requirements....

  6. Secure Real-Time Monitoring and Management of Smart Distribution Grid Using Shared Cellular Networks

    NARCIS (Netherlands)

    Nielsen, J.J.; Ganem, H.; Jorguseski, L.; Alic, K.; Smolnikar, M.; Zhu, Z.; Pratas, N.K.; Golinski, M.; Zhang, H.; Kuhar, U.; Fan, Z.; Svigelj, A.

    2017-01-01

    Electricity production and distribution is facing two major changes. First, production is shifting from classical energy sources such as coal and nuclear power toward renewable resources such as solar and wind. Second, consumption in the low voltage grid is expected to grow significantly due to the

  7. Preservation of correctness during system reconfiguration in Data Distribution Service for Real-Time Systems (DDS)

    NARCIS (Netherlands)

    Zieba, Bogumil; van Sinderen, Marten J.

    This paper addresses dynamic reconfiguration of distributed systems that use a publish/subscribe (pub/sub) middleware. The objective of dynamic reconfiguration is to evolve incrementally from one system configuration to another at run-time in order to e.g., ensure the reliability of the system. The

  8. Dynamic Scheduling of Object Invocations in Distributed Object Oriented Real-Time Systems

    DEFF Research Database (Denmark)

    Jørgensen, Bo Nørregaard; Joosen, Wouter

    1998-01-01

    This paper describes some of the issues that we investigate in order to develop distributed object computing middleware for application domains where timely cooperation and coordination between objects are crucial for guaranteeing correct system behavior. In particular, issues on admission contro...

  9. Secure Real-Time Monitoring and Management of Smart Distribution Grid using Shared Cellular Networks

    DEFF Research Database (Denmark)

    Nielsen, Jimmy Jessen; Ganem, Hervé; Jorguseski, Ljupco

    2017-01-01

    capabilities. Thanks to the advanced measurement devices, management framework, and secure communication infrastructure developed in the FP7 SUNSEED project, the Distribution System Operator (DSO) now has full observability of the energy flows at the medium/low voltage grid. Furthermore, the prosumers are able......, where the smart grid ICT solutions are provided through shared cellular LTE networks....

  10. Distributed Tactical Decision Support by Using Real-Time Database System

    Science.gov (United States)

    1987-11-01

    appendix A and detailed in depth in the Advanced Combat Direction System Specification (reference 5). The assumption is that ’ ime 0 (TO) of any contact...CONSTELLATION LAUNCH I F14A CAPM 330 350 10000 STOP At simulated engagement minute 30. the following orders are next submitted to the event generator...time of contact (ETC). There is the assumption in the ETC calculation that COURSE will change such that the new report would be on a dead- reckoning

  11. Quasi-real-time end-to-end simulations of ELT-scale adaptive optics systems on GPUs

    Science.gov (United States)

    Gratadour, Damien

    2011-09-01

    Our team has started the development of a code dedicated to GPUs for the simulation of AO systems at the E-ELT scale. It uses the CUDA toolkit and an original binding to Yorick (an open source interpreted language) to provide the user with a comprehensive interface. In this paper we present the first performance analysis of our simulation code, showing its ability to provide Shack-Hartmann (SH) images and measurements at the kHz scale for VLT-sized AO system and in quasi-real-time (up to 70 Hz) for ELT-sized systems on a single top-end GPU. The simulation code includes multiple layers atmospheric turbulence generation, ray tracing through these layers, image formation at the focal plane of every sub-apertures of a SH sensor using either natural or laser guide stars and centroiding on these images using various algorithms. Turbulence is generated on-the-fly giving the ability to simulate hours of observations without the need of loading extremely large phase screens in the global memory. Because of its performance this code additionally provides the unique ability to test real-time controllers for future AO systems under nominal conditions.

  12. Industrial Use of Distributed Generation in Real-Time Energy and Ancillary Service Markets

    Energy Technology Data Exchange (ETDEWEB)

    Hudson, C.R.

    2001-10-24

    Industrial consumers of energy now have the opportunity to participate directly in electricity generation. This report seeks to give the reader (1) insights into the various types of generation services that distributed generation (DG) units could provide, (2) a mechanism to evaluate the economics of using DG, (3) an overview of the status of DG deployment in selected states, and (4) a summary of the communication technologies involved with DG and what testing activities are needed to encourage industrial application of DG. Section 1 provides details on electricity markets and the types of services that can be offered. Subsequent sections in the report address the technical requirements for participating in such markets, the economic decision process that an industrial energy user should go through in evaluating distributed generation, the status of current deployment efforts, and the requirements for test-bed or field demonstration projects.

  13. Real-Time Analysis of an Active Distribution Network - Coordinated Frequency Control for Islanding Operation

    DEFF Research Database (Denmark)

    Cha, Seung-Tae

    distribution networks makes it possible to operate the distribution networks independently which is called islanding operation. However, it is a challenge to ensure secure and reliable operation of the islanded system due to a num-ber of reasons, e.g. low inertia in the islanded system, intermittency of some...... of the DERs, etc. Particularly during islanding operation, with relatively few DG units, the frequency and voltage control of the islanded system is not straightforward. DG units, specially based on renewable energy sources (RESs), i.e. wind and solar, have an inter-mittent nature and intrinsic...... system (BESS) and two secondary frequency control scenarios with BESS and DG units. During the island-ing transition, the frequency is regulated by the fast-acting primary control of the BESS. The secondary control of the main management system (MMS) detects the status of the BESS and tries to return...

  14. Industrial Use of Distributed Generation in Real-Time Energy and Ancillary Service Markets; TOPICAL

    International Nuclear Information System (INIS)

    Hudson, C.R.

    2001-01-01

    Industrial consumers of energy now have the opportunity to participate directly in electricity generation. This report seeks to give the reader (1) insights into the various types of generation services that distributed generation (DG) units could provide, (2) a mechanism to evaluate the economics of using DG, (3) an overview of the status of DG deployment in selected states, and (4) a summary of the communication technologies involved with DG and what testing activities are needed to encourage industrial application of DG. Section 1 provides details on electricity markets and the types of services that can be offered. Subsequent sections in the report address the technical requirements for participating in such markets, the economic decision process that an industrial energy user should go through in evaluating distributed generation, the status of current deployment efforts, and the requirements for test-bed or field demonstration projects

  15. Towards the Formal Verification of a Distributed Real-Time Automotive System

    Science.gov (United States)

    Endres, Erik; Mueller, Christian; Shadrin, Andrey; Tverdyshev, Sergey

    2010-01-01

    We present the status of a project which aims at building, formally and pervasively verifying a distributed automotive system. The target system is a gate-level model which consists of several interconnected electronic control units with independent clocks. This model is verified against the specification as seen by a system programmer. The automotive system is implemented on several FPGA boards. The pervasive verification is carried out using combination of interactive theorem proving (Isabelle/HOL) and model checking (LTL).

  16. Real-time-service-based Distributed Scheduling Scheme for IEEE 802.16j Networks

    OpenAIRE

    Kuo-Feng Huang; Shih-Jung Wu

    2013-01-01

    Supporting Quality of Service (QoS) guarantees for diverse multimedia services is the primary concern for IEEE802.16j networks. A scheduling scheme that satisfies the QoS requirements has become more important for wireless communications. We proposed an adaptive nontransparent-based distributed scheduling scheme (ANDS) for IEEE 802.16j networks. ANDS comprises three major components: Priority Assignment, Resource Allocation, Preserved Bandwidth Adjustment. Different service-type connections p...

  17. Particle Sampling and Real Time Size Distribution Measurement in H2/O2/TEOS Diffusion Flame

    International Nuclear Information System (INIS)

    Ahn, K.H.; Jung, C.H.; Choi, M.; Lee, J.S.

    2001-01-01

    Growth characteristics of silica particles have been studied experimentally using in situ particle sampling technique from H 2 /O 2 /Tetraethylorthosilicate (TEOS) diffusion flame with carefully devised sampling probe. The particle morphology and the size comparisons are made between the particles sampled by the local thermophoretic method from the inside of the flame and by the electrostatic collector sampling method after the dilution sampling probe. The Transmission Electron Microscope (TEM) image processed data of these two sampling techniques are compared with Scanning Mobility Particle Sizer (SMPS) measurement. TEM image analysis of two sampling methods showed a good agreement with SMPS measurement. The effects of flame conditions and TEOS flow rates on silica particle size distributions are also investigated using the new particle dilution sampling probe. It is found that the particle size distribution characteristics and morphology are mostly governed by the coagulation process and sintering process in the flame. As the flame temperature increases, the effect of coalescence or sintering becomes an important particle growth mechanism which reduces the coagulation process. However, if the flame temperature is not high enough to sinter the aggregated particles then the coagulation process is a dominant particle growth mechanism. In a certain flame condition a secondary particle formation is observed which results in a bimodal particle size distribution

  18. Real-Time and High-Fidelity Simulation Environment for Autonomous Ground Vehicle Dynamics

    Science.gov (United States)

    Cameron, Jonathan; Myint, Steven; Kuo, Calvin; Jain, Abhi; Grip, Havard; Jayakumar, Paramsothy; Overholt, Jim

    2013-01-01

    This paper reports on a collaborative project between U.S. Army TARDEC and Jet Propulsion Laboratory (JPL) to develop a unmanned ground vehicle (UGV) simulation model using the ROAMS vehicle modeling framework. Besides modeling the physical suspension of the vehicle, the sensing and navigation of the HMMWV vehicle are simulated. Using models of urban and off-road environments, the HMMWV simulation was tested in several ways, including navigation in an urban environment with obstacle avoidance and the performance of a lane change maneuver.

  19. A new doubly discrete analogue of smoke ring flow and the real time simulation of fluid flow

    International Nuclear Information System (INIS)

    Pinkall, Ulrich; Springborn, Boris; Weissmann, Steffen

    2007-01-01

    Modelling incompressible ideal fluids as a finite collection of vortex filaments is important in physics (super-fluidity, models for the onset of turbulence) as well as for numerical algorithms used in computer graphics for the real time simulation of smoke. Here we introduce a time-discrete evolution equation for arbitrary closed polygons in 3-space that is a discretization of the localized induction approximation of filament motion. This discretization shares with its continuum limit the property that it is a completely integrable system. We apply this polygon evolution to a significant improvement of the numerical algorithms used in computer graphics

  20. Real-time updating of the flood frequency distribution through data assimilation

    Science.gov (United States)

    Aguilar, Cristina; Montanari, Alberto; Polo, María-José

    2017-07-01

    We explore the memory properties of catchments for predicting the likelihood of floods based on observations of average flows in pre-flood seasons. Our approach assumes that flood formation is driven by the superimposition of short- and long-term perturbations. The former is given by the short-term meteorological forcing leading to infiltration and/or saturation excess, while the latter is originated by higher-than-usual storage in the catchment. To exploit the above sensitivity to long-term perturbations, a meta-Gaussian model and a data assimilation approach are implemented for updating the flood frequency distribution a season in advance. Accordingly, the peak flow in the flood season is predicted in probabilistic terms by exploiting its dependence on the average flow in the antecedent seasons. We focus on the Po River at Pontelagoscuro and the Danube River at Bratislava. We found that the shape of the flood frequency distribution is noticeably impacted by higher-than-usual flows occurring up to several months earlier. The proposed technique may allow one to reduce the uncertainty associated with the estimation of flood frequency.

  1. Concurrent heterogeneous neural model simulation on real-time neuromimetic hardware.

    Science.gov (United States)

    Rast, Alexander; Galluppi, Francesco; Davies, Sergio; Plana, Luis; Patterson, Cameron; Sharp, Thomas; Lester, David; Furber, Steve

    2011-11-01

    Dedicated hardware is becoming increasingly essential to simulate emerging very-large-scale neural models. Equally, however, it needs to be able to support multiple models of the neural dynamics, possibly operating simultaneously within the same system. This may be necessary either to simulate large models with heterogeneous neural types, or to simplify simulation and analysis of detailed, complex models in a large simulation by isolating the new model to a small subpopulation of a larger overall network. The SpiNNaker neuromimetic chip is a dedicated neural processor able to support such heterogeneous simulations. Implementing these models on-chip uses an integrated library-based tool chain incorporating the emerging PyNN interface that allows a modeller to input a high-level description and use an automated process to generate an on-chip simulation. Simulations using both LIF and Izhikevich models demonstrate the ability of the SpiNNaker system to generate and simulate heterogeneous networks on-chip, while illustrating, through the network-scale effects of wavefront synchronisation and burst gating, methods that can provide effective behavioural abstractions for large-scale hardware modelling. SpiNNaker's asynchronous virtual architecture permits greater scope for model exploration, with scalable levels of functional and temporal abstraction, than conventional (or neuromorphic) computing platforms. The complete system illustrates a potential path to understanding the neural model of computation, by building (and breaking) neural models at various scales, connecting the blocks, then comparing them against the biology: computational cognitive neuroscience. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Transient simulation for a real-time operator advisor expert system

    International Nuclear Information System (INIS)

    Jakubowski, T.; Hajek, B.K.; Miller, D.W.; Bhatnagar, R.

    1990-01-01

    An Operator Advisor (OA) consisting of four integrated expert systems has been under development at The Ohio State University since 1985. The OA, designed for a General Electric BWR-6 plant, has used the Perry Nuclear Power Plants full scope simulator near Cleveland, Ohio (USA) as the reference plant. The primary goal of this development has been to provide a single system which not only performs monitoring and diagnosis functions, but also provides fault mitigation procedures to the operator, monitors the performance of these procedures and provides backup procudures should the initial ones fail. To test the system off line, a transient event simulation methodology has been developed. The simulator employs event scenarios from the Perry simulator. Scenarios are selected to test both inter- and intra-modular system behavior and response and to verify the consistency and accuracy of the knowledge base. This paper describes the OA architecture and design and the transient simulation. A discussion of a sample scenario test, including the rationale for scenario selection, is included as an example. The results of the testing demonstrate the value of off line transient simulations in that they verify system operation and help to identify characteristics requiring further improvements

  3. Finite Element Methods for real-time Haptic Feedback of Soft-Tissue Models in Virtual Reality Simulators

    Science.gov (United States)

    Frank, Andreas O.; Twombly, I. Alexander; Barth, Timothy J.; Smith, Jeffrey D.; Dalton, Bonnie P. (Technical Monitor)

    2001-01-01

    We have applied the linear elastic finite element method to compute haptic force feedback and domain deformations of soft tissue models for use in virtual reality simulators. Our results show that, for virtual object models of high-resolution 3D data (>10,000 nodes), haptic real time computations (>500 Hz) are not currently possible using traditional methods. Current research efforts are focused in the following areas: 1) efficient implementation of fully adaptive multi-resolution methods and 2) multi-resolution methods with specialized basis functions to capture the singularity at the haptic interface (point loading). To achieve real time computations, we propose parallel processing of a Jacobi preconditioned conjugate gradient method applied to a reduced system of equations resulting from surface domain decomposition. This can effectively be achieved using reconfigurable computing systems such as field programmable gate arrays (FPGA), thereby providing a flexible solution that allows for new FPGA implementations as improved algorithms become available. The resulting soft tissue simulation system would meet NASA Virtual Glovebox requirements and, at the same time, provide a generalized simulation engine for any immersive environment application, such as biomedical/surgical procedures or interactive scientific applications.

  4. Real time Monte Carlo simulation for evaluation of patient doses involved in radiological examinations

    International Nuclear Information System (INIS)

    Fulea, D.; Cosma, C.

    2006-01-01

    In order to apply the Monte Carlo simulation technique for usual radiological examinations we developed a Pc program, 'IradMed', written entirely in Java. The main purpose of this program is to compute the organ doses and the effective dose of patients, which are exposed at a X-ray beam having photon energies in 10 to 150 keV radiodiagnostic range. Three major radiological procedures are considered, namely mammography, radiography and CT. The fluoroscopy implies an irregular geometry and therefore it is neglected. Nevertheless, a gross estimation of patient doses can be made taking into account the fluoroscopy as being composed of several radiographic examinations applied in different anatomical regions. The interactions between radiation and matter are well-known, and the accuracy of the calculation is limited by the accuracy of the anatomical model used to describe actual patients and by characterisation of the radiation field applied. In this version of IradMed, it is assumed that the absorbed dose is equal with kerma for all tissues. No procedure has been used to take account of the finite range of the secondary electrons that are produced by photoelectric or Compton interactions. These ranges are small compared with the dimensions of the organs, and the absorbed dose will not change abruptly with distance except at boundary where composition and density change. However these boundary effects would have little effect in the determination of the average doses to almost all organs, except the active bone marrow which is treated separately. Another justification for this kerma approximation is the fact that the sum of all electron energies that exit the organ is statistically equal with the sum of all electron energies that enter in that particular organ. In this version of program, it is considered the following interactions: the Rayleigh scattering, the Compton scattering and the photoelectric effect. The Compton scattering is modeled by several methods which

  5. Real time Monte Carlo simulation for evaluation of patient doses involved in radiological examinations

    Energy Technology Data Exchange (ETDEWEB)

    Fulea, D [Institute of Public Health ' Prof.Dr.Iuliu Moldovan' , Cluj-Napoca (Romania); Cosma, C [Babes-Bolyai Univ., Faculty of Physics, Cluj-Napoca (Romania)

    2006-07-01

    In order to apply the Monte Carlo simulation technique for usual radiological examinations we developed a Pc program, 'IradMed', written entirely in Java. The main purpose of this program is to compute the organ doses and the effective dose of patients, which are exposed at a X-ray beam having photon energies in 10 to 150 keV radiodiagnostic range. Three major radiological procedures are considered, namely mammography, radiography and CT. The fluoroscopy implies an irregular geometry and therefore it is neglected. Nevertheless, a gross estimation of patient doses can be made taking into account the fluoroscopy as being composed of several radiographic examinations applied in different anatomical regions. The interactions between radiation and matter are well-known, and the accuracy of the calculation is limited by the accuracy of the anatomical model used to describe actual patients and by characterisation of the radiation field applied. In this version of IradMed, it is assumed that the absorbed dose is equal with kerma for all tissues. No procedure has been used to take account of the finite range of the secondary electrons that are produced by photoelectric or Compton interactions. These ranges are small compared with the dimensions of the organs, and the absorbed dose will not change abruptly with distance except at boundary where composition and density change. However these boundary effects would have little effect in the determination of the average doses to almost all organs, except the active bone marrow which is treated separately. Another justification for this kerma approximation is the fact that the sum of all electron energies that exit the organ is statistically equal with the sum of all electron energies that enter in that particular organ. In this version of program, it is considered the following interactions: the Rayleigh scattering, the Compton scattering and the photoelectric effect. The Compton scattering is modeled by several methods which

  6. Real time Monte Carlo simulation for evaluation of patient doses involved in radiological examinations

    Energy Technology Data Exchange (ETDEWEB)

    Fulea, D. [Institute of Public Health ' Prof.Dr.Iuliu Moldovan' , Cluj-Napoca (Romania); Cosma, C. [Babes-Bolyai Univ., Faculty of Physics, Cluj-Napoca (Romania)

    2006-07-01

    In order to apply the Monte Carlo simulation technique for usual radiological examinations we developed a Pc program, 'IradMed', written entirely in Java. The main purpose of this program is to compute the organ doses and the effective dose of patients, which are exposed at a X-ray beam having photon energies in 10 to 150 keV radiodiagnostic range. Three major radiological procedures are considered, namely mammography, radiography and CT. The fluoroscopy implies an irregular geometry and therefore it is neglected. Nevertheless, a gross estimation of patient doses can be made taking into account the fluoroscopy as being composed of several radiographic examinations applied in different anatomical regions. The interactions between radiation and matter are well-known, and the accuracy of the calculation is limited by the accuracy of the anatomical model used to describe actual patients and by characterisation of the radiation field applied. In this version of IradMed, it is assumed that the absorbed dose is equal with kerma for all tissues. No procedure has been used to take account of the finite range of the secondary electrons that are produced by photoelectric or Compton interactions. These ranges are small compared with the dimensions of the organs, and the absorbed dose will not change abruptly with distance except at boundary where composition and density change. However these boundary effects would have little effect in the determination of the average doses to almost all organs, except the active bone marrow which is treated separately. Another justification for this kerma approximation is the fact that the sum of all electron energies that exit the organ is statistically equal with the sum of all electron energies that enter in that particular organ. In this version of program, it is considered the following interactions: the Rayleigh scattering, the Compton scattering and the photoelectric effect. The Compton scattering is modeled by several

  7. Distributed radar network for real-time tracking of bullet trajectory

    Science.gov (United States)

    Zhang, Yimin; Li, Xin; Jin, Yuanwei; Amin, Moeness G.; Eydgahi, Ali

    2009-05-01

    Gunshot detection, sniper localization, and bullet trajectory prediction are of significant importance in military and homeland security applications. While the majority of existing work is based on acoustic and electro-optical sensors, this paper develops a framework of networked radar systems that uses distributed radar sensor networks to achieve the aforementioned objectives. The use of radio frequency radar systems allows the achievement of subtime- of-flight tracking response, enabling to response before the bullet reaches its target and, as such, effectively leading to the reduction of injuries and casualties in military and homeland security operations. The focus of this paper is to examine the MIMO radar concept with concurrent transmission of low-correlation waveforms from multiple radar sets to ensure wide surveillance coverage and maintain a high waveform repetition frequency for long coherent time interval required to achieve return signal concentration.

  8. Real-Time Dynamic Simulation of Korean Power Grid for Frequency Regulation Control by MW Battery Energy Storage System

    Directory of Open Access Journals (Sweden)

    Tae-Hwan Jin

    2016-12-01

    Full Text Available The aim of this study was to develop a real-time dynamic simulator of a power grid with power plant and battery model. The simulator was used to investigate the frequency control characteristics of a megawatt-scale high-capacity energy storage system connected to the electric power grid. In this study, a lithium-ion secondary battery was chosen as one of the batteries for a grid-connected model. The dynamics of the model was analysed in both steady and transient states. The frequency control system of the battery model plays a role in regulating the grid frequency by controlling the power of energy storage systems according to process variables and grid frequencies. The power grid model based on the current power network of South Korea, included power plants, substations and power demands. The power supply is classified by the type of turbine generator as thermal, nuclear, hydro power, pumped power storage, combined power plants, and batteries, including high-capacity energy storage systems rated for a maximum of 500 MW. This study deals with an installed capacity of 87.17 GW and peak load of 77.30 GW in the Korean power grid. For 24 hours of operation, the maximum and minimum power outputs were simulated as 61.59 GW and 46.32 GW, respectively. The commercialized real-time dynamic simulation software ProTRAX was used. The simulation was conducted to observe the operation characteristics of the frequency control system during a breakdown of power plants, as well as under governor-free operation, auto generation control operation, and with the battery energy storage system connected. The results show that the model is valid for each power plant breakdown simulation. They also confirm that the output power and frequency controls of the battery operated well during simulations.

  9. OVNI: a full-size real-time power system simulator

    Energy Technology Data Exchange (ETDEWEB)

    Marti, J R; Linares, L R; Rosales, R; Dommel, H W [British Columbia Univ., Vancouver, BC (Canada)

    1998-12-31

    The concept and work-in-progress to develop a computer-based power system simulator that would mimic as closely as possible the behaviour of an actual power system, was described. The simulator, dubbed OVNI for Object Virtual Network Integrator, is capable of running continuously. It produces at each discreet time instant, the correct voltages and currents in a power system. OVNI is being implemented using a network of off-the-shelf Pentium Pro 200 MHz workstations. The Ada 95 language is used to satisfy object-oriented requirements and provide the code with the reliability required for mission-critical applications. An important characteristic of OVNI is its fully graphical and integrated simulation environment. System events can be directly applied to the simulator and outputs probed as the simulator is running. Input events can originate from user action or directly through A/D boards. Output probes can also be directed to the screen as running plots, or forwarded through D/A boards. 6 refs., 6 figs.

  10. OVNI: a full-size real-time power system simulator

    Energy Technology Data Exchange (ETDEWEB)

    Marti, J. R.; Linares, L. R.; Rosales, R.; Dommel, H. W. [British Columbia Univ., Vancouver, BC (Canada)

    1997-12-31

    The concept and work-in-progress to develop a computer-based power system simulator that would mimic as closely as possible the behaviour of an actual power system, was described. The simulator, dubbed OVNI for Object Virtual Network Integrator, is capable of running continuously. It produces at each discreet time instant, the correct voltages and currents in a power system. OVNI is being implemented using a network of off-the-shelf Pentium Pro 200 MHz workstations. The Ada 95 language is used to satisfy object-oriented requirements and provide the code with the reliability required for mission-critical applications. An important characteristic of OVNI is its fully graphical and integrated simulation environment. System events can be directly applied to the simulator and outputs probed as the simulator is running. Input events can originate from user action or directly through A/D boards. Output probes can also be directed to the screen as running plots, or forwarded through D/A boards. 6 refs., 6 figs.

  11. An Architecture Approach for 3D Render Distribution using Mobile Devices in Real Time

    Directory of Open Access Journals (Sweden)

    Holman Bolivar-Baron

    2015-06-01

    Full Text Available Nowadays, video games such as Massively Multiplayer Online Game (MMOG have become cultural mediators. Mobile games contribute to a large number of downloads and potential benefits in the applications market. Although processing power of mobile devices increases the bandwidth transmission, a poor network connectivity may bottleneck Gaming as a Service (GaaS. In order to enhance performance in digital ecosystem, processing tasks are distributed among thin client devices and robust servers. This research is based on the method ‘divide and rule’, that is, volumetric surfaces are subdivided using a tree-KD of sequence of scenes in a game, so reducing the surface into small sets of points. Reconstruction efficiency is improved, because the search of data is performed in local and small regions. Processes are modeled through a finite set of states that are built using Hidden Markov Models with domains configured by heuristics. Six test that control the states of each heuristic, including the number of intervals are carried out to validate the proposed model. This validation concludes that the proposed model optimizes response frames per second, in a sequence of interactions.

  12. Fiber optic distributed chemical sensor for the real time detection of hydrocarbon fuel leaks

    Science.gov (United States)

    Mendoza, Edgar; Kempen, C.; Esterkin, Yan; Sun, Sunjian

    2015-09-01

    With the increase worldwide demand for hydrocarbon fuels and the vast development of new fuel production and delivery infrastructure installations around the world, there is a growing need for reliable hydrocarbon fuel leak detection technologies to provide safety and reduce environmental risks. Hydrocarbon leaks (gas or liquid) pose an extreme danger and need to be detected very quickly to avoid potential disasters. Gas leaks have the greatest potential for causing damage due to the explosion risk from the dispersion of gas clouds. This paper describes progress towards the development of a fast response, high sensitivity, distributed fiber optic fuel leak detection (HySense™) system based on the use of an optical fiber that uses a hydrocarbon sensitive fluorescent coating to detect the presence of fuel leaks present in close proximity along the length of the sensor fiber. The HySense™ system operates in two modes, leak detection and leak localization, and will trigger an alarm within seconds of exposure contact. The fast and accurate response of the sensor provides reliable fluid leak detection for pipelines, storage tanks, airports, pumps, and valves to detect and minimize any potential catastrophic damage.

  13. Real-time distributed fiber optic sensor for security systems: Performance, event classification and nuisance mitigation

    Science.gov (United States)

    Mahmoud, Seedahmed S.; Visagathilagar, Yuvaraja; Katsifolis, Jim

    2012-09-01

    The success of any perimeter intrusion detection system depends on three important performance parameters: the probability of detection (POD), the nuisance alarm rate (NAR), and the false alarm rate (FAR). The most fundamental parameter, POD, is normally related to a number of factors such as the event of interest, the sensitivity of the sensor, the installation quality of the system, and the reliability of the sensing equipment. The suppression of nuisance alarms without degrading sensitivity in fiber optic intrusion detection systems is key to maintaining acceptable performance. Signal processing algorithms that maintain the POD and eliminate nuisance alarms are crucial for achieving this. In this paper, a robust event classification system using supervised neural networks together with a level crossings (LCs) based feature extraction algorithm is presented for the detection and recognition of intrusion and non-intrusion events in a fence-based fiber-optic intrusion detection system. A level crossings algorithm is also used with a dynamic threshold to suppress torrential rain-induced nuisance alarms in a fence system. Results show that rain-induced nuisance alarms can be suppressed for rainfall rates in excess of 100 mm/hr with the simultaneous detection of intrusion events. The use of a level crossing based detection and novel classification algorithm is also presented for a buried pipeline fiber optic intrusion detection system for the suppression of nuisance events and discrimination of intrusion events. The sensor employed for both types of systems is a distributed bidirectional fiber-optic Mach-Zehnder (MZ) interferometer.

  14. Real-time qualitative study of forsterite crystal - Melt lithium distribution by laser-induced breakdown spectroscopy

    Science.gov (United States)

    Lebedev, V. F.; Makarchuk, P. S.; Stepanov, D. N.

    2017-11-01

    A factor of lithium distribution between single-crystal forsterite (Cr,Li:Mg2SiO4) and its melt are studied by laser-induced breakdown spectroscopy. Lithium content in the crystalline phase is found to achieve a saturation at relatively low Li concentration in the melt (about 0.02%wt.). An algorithm and software are developed for real-time analysis of the studied spectra of lithium trace amounts at wide variation of the plasma radiation intensity. The analyzed plasma spectra processing method is based on the calculation of lithium emission part in the total emission of the target plasma for each recorded spectrum followed by the error estimation for the series of measurements in the normal distribution approximation.

  15. Motor simulation and the coordination of self and other in real-time joint action.

    Science.gov (United States)

    Novembre, Giacomo; Ticini, Luca F; Schütz-Bosbach, Simone; Keller, Peter E

    2014-08-01

    Joint actions require the integration of simultaneous self- and other-related behaviour. Here, we investigated whether this function is underpinned by motor simulation, that is the capacity to represent a perceived action in terms of the neural resources required to execute it. This was tested in a music performance experiment wherein on-line brain stimulation (double-pulse transcranial magnetic stimulation, dTMS) was employed to interfere with motor simulation. Pianists played the right-hand part of piano pieces in synchrony with a recording of the left-hand part, which had (Trained) or had not (Untrained) been practiced beforehand. Training was assumed to enhance motor simulation. The task required adaptation to tempo changes in the left-hand part that, in critical conditions, were preceded by dTMS delivered over the right primary motor cortex. Accuracy of tempo adaptation following dTMS or sham stimulations was compared across Trained and Untrained conditions. Results indicate that dTMS impaired tempo adaptation accuracy only during the perception of trained actions. The magnitude of this interference was greater in empathic individuals possessing a strong tendency to adopt others' perspectives. These findings suggest that motor simulation provides a functional resource for the temporal coordination of one's own behaviour with others in dynamic social contexts. © The Author (2013). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  16. Modelling and real-time simulation of continuous-discrete systems in mechatronics

    Energy Technology Data Exchange (ETDEWEB)

    Lindow, H. [Rostocker, Magdeburg (Germany)

    1996-12-31

    This work presents a methodology for simulation and modelling of systems with continuous - discrete dynamics. It derives hybrid discrete event models from Lagrange`s equations of motion. This method combines continuous mechanical, electrical and thermodynamical submodels on one hand with discrete event models an the other hand into a hybrid discrete event model. This straight forward software development avoids numeric overhead.

  17. A prototype system for real time computer animation of slow traffic in a driving simulator

    NARCIS (Netherlands)

    Roerdink, JBTM; van Delden, MJB; Hin, AJS; van Wolffelaar, PC; Thalmann, NM; Skala,

    1997-01-01

    The Traffic Research Centre (TRC) of the University of Groningen in the Netherlands has developed a driving simulator with 'intelligent' computer-controlled traffic, consisting at the moment only of saloon cars. The range of possible applications would be greatly enhanced if other traffic

  18. A Prototype System for Real Time Computer Animation of Slow Traffic in a Driving Simulator

    NARCIS (Netherlands)

    Roerdink, Jos B.T.M.; Delden, Mattijs J.B. van; Hin, Andrea J.S.; Wolffelaar, Peter C. van

    1997-01-01

    The Traffic Research Centre (TRC) of the University of Groningen in the Netherlands has developed a driving simulator with ‘intelligent’ computer-controlled traffic, consisting at the moment only of saloon cars. The range of possible applications would be greatly enhanced if other traffic

  19. Real-Time Computer Animation of Bicyclists and Pedestrians in a Driving Simulator

    NARCIS (Netherlands)

    Roerdink, Jos B.T.M.; Delden, Mattijs J.B. van; Hin, Andrea J.S.; Wolffelaar, Peter C. van

    1996-01-01

    The Traffic Research Centre (TRC) of the University of Groningen in the Netherlands has developed a driving simulator with ‘intelligent’ computer-controlled traffic, consisting at the moment only of saloon cars. The range of possible applications would be greatly enhanced if other traffic

  20. Real-Time Animation Using a Mix of Physical Simulation and Kinematics

    NARCIS (Netherlands)

    van Welbergen, H.; Zwiers, Jakob; Ruttkay, Z.M.

    2009-01-01

    Expressive animation (such as gesturing or conducting) is typically generated using procedural animation techniques. These techniques offer precision in both timing and limb placement, but they lack physical realism. On the other hand, physical simulation offers physical realism, but does not

  1. Face-based smoothed finite element method for real-time simulation of soft tissue

    Science.gov (United States)

    Mendizabal, Andrea; Bessard Duparc, Rémi; Bui, Huu Phuoc; Paulus, Christoph J.; Peterlik, Igor; Cotin, Stéphane

    2017-03-01

    In soft tissue surgery, a tumor and other anatomical structures are usually located using the preoperative CT or MR images. However, due to the deformation of the concerned tissues, this information suffers from inaccuracy when employed directly during the surgery. In order to account for these deformations in the planning process, the use of a bio-mechanical model of the tissues is needed. Such models are often designed using the finite element method (FEM), which is, however, computationally expensive, in particular when a high accuracy of the simulation is required. In our work, we propose to use a smoothed finite element method (S-FEM) in the context of modeling of the soft tissue deformation. This numerical technique has been introduced recently to overcome the overly stiff behavior of the standard FEM and to improve the solution accuracy and the convergence rate in solid mechanics problems. In this paper, a face-based smoothed finite element method (FS-FEM) using 4-node tetrahedral elements is presented. We show that in some cases, the method allows for reducing the number of degrees of freedom, while preserving the accuracy of the discretization. The method is evaluated on a simulation of a cantilever beam loaded at the free end and on a simulation of a 3D cube under traction and compression forces. Further, it is applied to the simulation of the brain shift and of the kidney's deformation. The results demonstrate that the method outperforms the standard FEM in a bending scenario and that has similar accuracy as the standard FEM in the simulations of the brain-shift and of the kidney's deformation.

  2. Real-time Risk Assessment for Aids to Navigation Using Fuzzy-FSA on Three-Dimensional Simulation System

    Directory of Open Access Journals (Sweden)

    Jinbiao Chen

    2014-06-01

    Full Text Available The risk level of the Aids to Navigation (AtoNs can reflect the ship navigation safety level in the channel to some extent. In order to appreciate the risk level of the aids to navigation (AtoNs in a navigation channel and to provide some decision-making suggestions for the AtoNs Maintenance and Management Department, the risk assessment index system of the AtoNs was built considering the advanced experience of IALA. Under the Formal Safety Assessment frame, taking the advantages of the fuzzy comprehensive evaluation method, the fuzzy-FSA model of risk assessment for aids to navigation was established. The model was implemented for the assessment of aids to navigation in Shanghai area based on the aids to navigation three-dimensional simulation system. The real-time data were extracted from the existing information system of aids to navigation, and the real-time risk assessment for aids to navigation of the chosen channel was performed on platform of the three-dimensional simulation system, with the risk assessment software. Specifically, the deep-water channel of the Yangtze River estuary was taken as an example to illustrate the general assessment procedure. The method proposed presents practical significance and application prospect on the maintenance and management of the aids to navigation.

  3. EDUCATIONAL COMPUTER SIMULATION EXPERIMENT «REAL-TIME SINGLE-MOLECULE IMAGING OF QUANTUM INTERFERENCE»

    Directory of Open Access Journals (Sweden)

    Alexander V. Baranov

    2015-01-01

    Full Text Available Taking part in the organized project activities students of the technical University create virtual physics laboratories. The article gives an example of the student’s project-computer modeling and visualization one of the most wonderful manifestations of reality-quantum interference of particles. The real experiment with heavy organic fluorescent molecules is used as a prototype for this computer simulation. The student’s software product can be used in informational space of the system of open education.

  4. Real-time cavity simulator-based low-level radio-frequency test bench and applications for accelerators

    Science.gov (United States)

    Qiu, Feng; Michizono, Shinichiro; Miura, Takako; Matsumoto, Toshihiro; Liu, Na; Wibowo, Sigit Basuki

    2018-03-01

    A Low-level radio-frequency (LLRF) control systems is required to regulate the rf field in the rf cavity used for beam acceleration. As the LLRF system is usually complex, testing of the basic functions or control algorithms of this system in real time and in advance of beam commissioning is strongly recommended. However, the equipment necessary to test the LLRF system, such as superconducting cavities and high-power rf sources, is very expensive; therefore, we have developed a field-programmable gate array (FPGA)-based cavity simulator as a substitute for real rf cavities. Digital models of the cavity and other rf systems are implemented in the FPGA. The main components include cavity baseband models for the fundamental and parasitic modes, a mechanical model of the Lorentz force detuning, and a model of the beam current. Furthermore, in our simulator, the disturbance model used to simulate the power-supply ripples and microphonics is also carefully considered. Based on the presented cavity simulator, we have established an LLRF system test bench that can be applied to different cavity operational conditions. The simulator performance has been verified by comparison with real cavities in KEK accelerators. In this paper, the development and implementation of this cavity simulator is presented first, and the LLRF test bench based on the presented simulator is constructed. The results are then compared with those for KEK accelerators. Finally, several LLRF applications of the cavity simulator are illustrated.

  5. Real-time cavity simulator-based low-level radio-frequency test bench and applications for accelerators

    Directory of Open Access Journals (Sweden)

    Feng Qiu

    2018-03-01

    Full Text Available A Low-level radio-frequency (LLRF control systems is required to regulate the rf field in the rf cavity used for beam acceleration. As the LLRF system is usually complex, testing of the basic functions or control algorithms of this system in real time and in advance of beam commissioning is strongly recommended. However, the equipment necessary to test the LLRF system, such as superconducting cavities and high-power rf sources, is very expensive; therefore, we have developed a field-programmable gate array (FPGA-based cavity simulator as a substitute for real rf cavities. Digital models of the cavity and other rf systems are implemented in the FPGA. The main components include cavity baseband models for the fundamental and parasitic modes, a mechanical model of the Lorentz force detuning, and a model of the beam current. Furthermore, in our simulator, the disturbance model used to simulate the power-supply ripples and microphonics is also carefully considered. Based on the presented cavity simulator, we have established an LLRF system test bench that can be applied to different cavity operational conditions. The simulator performance has been verified by comparison with real cavities in KEK accelerators. In this paper, the development and implementation of this cavity simulator is presented first, and the LLRF test bench based on the presented simulator is constructed. The results are then compared with those for KEK accelerators. Finally, several LLRF applications of the cavity simulator are illustrated.

  6. Network Dynamics with BrainX3: A Large-Scale Simulation of the Human Brain Network with Real-Time Interaction

    Directory of Open Access Journals (Sweden)

    Xerxes D. Arsiwalla

    2015-02-01

    Full Text Available BrainX3 is a large-scale simulation of human brain activity with real-time interaction, rendered in 3D in a virtual reality environment, which combines computational power with human intuition for the exploration and analysis of complex dynamical networks. We ground this simulation on structural connectivity obtained from diffusion spectrum imaging data and model it on neuronal population dynamics. Users can interact with BrainX3 in real-time by perturbing brain regions with transient stimulations to observe reverberating network activity, simulate lesion dynamics or implement network analysis functions from a library of graph theoretic measures. BrainX3 can thus be used as a novel immersive platform for real-time exploration and analysis of dynamical activity patterns in brain networks, both at rest or in a task-related state, for discovery of signaling pathways associated to brain function and/or dysfunction and as a tool for virtual neurosurgery. Our results demonstrate these functionalities and shed insight on the dynamics of the resting-state attractor. Specifically, we found that a noisy network seems to favor a low firing attractor state. We also found that the dynamics of a noisy network is less resilient to lesions. Our simulations on TMS perturbations show that even though TMS inhibits most of the network, it also sparsely excites a few regions. This is presumably, due to anti-correlations in the dynamics and suggests that even a lesioned network can show sparsely distributed increased activity compared to healthy resting-state, over specific brain areas.

  7. Real-Time Million-Synapse Simulation of Rat Barrel Cortex

    Directory of Open Access Journals (Sweden)

    Thomas eSharp

    2014-05-01

    Full Text Available Simulations of neural circuits are bounded in scale and speed by available computing resources, and particularly by the differences in parallelism and communication patterns between the brain and high-performance computers. SpiNNaker is a computer architecture designed to address this problem by emulating the structure and function of neural tissue, using very many low-power processors and an interprocessor communication mechanism inspired by axonal arbors. Here we demonstrate that thousand-processor SpiNNaker prototypes can simulate models of the rodent barrel system comprising fifty thousand neurons and fifty million synapses. We use the PyNN library to specify models, and the intrinsic features of Python to control experimental procedures and analysis. The models reproduce known thalamocortical response transformations, exhibit known, balanced dynamics of excitation and inhibition, and show a spatiotemporal spread of activity though the superficial cortical layers. These demonstrations are a significant step towards tractable simulations of entire cortical areas on the million-processor SpiNNaker machines in development.

  8. Real-time million-synapse simulation of rat barrel cortex.

    Science.gov (United States)

    Sharp, Thomas; Petersen, Rasmus; Furber, Steve

    2014-01-01

    Simulations of neural circuits are bounded in scale and speed by available computing resources, and particularly by the differences in parallelism and communication patterns between the brain and high-performance computers. SpiNNaker is a computer architecture designed to address this problem by emulating the structure and function of neural tissue, using very many low-power processors and an interprocessor communication mechanism inspired by axonal arbors. Here we demonstrate that thousand-processor SpiNNaker prototypes can simulate models of the rodent barrel system comprising 50,000 neurons and 50 million synapses. We use the PyNN library to specify models, and the intrinsic features of Python to control experimental procedures and analysis. The models reproduce known thalamocortical response transformations, exhibit known, balanced dynamics of excitation and inhibition, and show a spatiotemporal spread of activity though the superficial cortical layers. These demonstrations are a significant step toward tractable simulations of entire cortical areas on the million-processor SpiNNaker machines in development.

  9. Development of the Real-time Core and Thermal-Hydraulic Models for Kori-1 Simulator

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Jin Hyuk; Lee, Myeong Soo; Hwang, Do Hyun; Byon, Soo Jin [KEPRI, Daejeon (Korea, Republic of)

    2010-10-15

    The operation of the Kori-Unit 1 (1723.5MWt) is expanded to additional 10 years with upgrades of the Main Control Room (MCR). Therefore, the revision of the procedures, performance tests and works related with the exchange of the Main Control Board (MCB) are currently carried out. And as a part of it, the fullscope simulator for the Kori-1 is being developed for the purpose of the pre-operation and emergence response capability for the operators. The purpose of this paper is to report on the performance of the developed neutronics and thermal-hydraulic (TH) models of Kori Unit 1 simulator. The neutronics model is based on the NESTLE code and TH model based on the RELAP5/MOD3 thermal-hydraulics analysis code which was funded as FY-93 LDRD Project 7201 and is running on the commercial simulator environment tool (the 3KeyMaster{sup TM} of the WSC). As some examples for the verification of the developed neutronics and TH models, some figures are provided. The outputs of the developed neutronics and TH models are in accord with the Nuclear Design Report (NDR) and Final Safety Analysis Report (FSAR) of the reference plant

  10. Real-time systems

    OpenAIRE

    Badr, Salah M.; Bruztman, Donald P.; Nelson, Michael L.; Byrnes, Ronald Benton

    1992-01-01

    This paper presents an introduction to the basic issues involved in real-time systems. Both real-time operating sys and real-time programming languages are explored. Concurrent programming and process synchronization and communication are also discussed. The real-time requirements of the Naval Postgraduate School Autonomous Under Vehicle (AUV) are then examined. Autonomous underwater vehicle (AUV), hard real-time system, real-time operating system, real-time programming language, real-time sy...

  11. Combining driveline and suspension models for real-time simulations / Kombination von Antriebs- und Fahrwerksmodellen zur Echtzeit-Simulation

    NARCIS (Netherlands)

    Vis, M.A.; Venne, J.W.C.M. van de; Vink, W.J.; Steen, M. van der; Lupker, H.A.

    2000-01-01

    A Modular Vehicle (MoVe) library is presented, containing driveline and vehicle dynamics component models. The library is built in Matlab\\Simulink, taking advantage of its modular capabilities and real-time application possibilities. Its use is demonstrated with the construction of a 4-wheel car,

  12. Real-time distribution of pelagic fish: combining hydroacoustics, GIS and spatial modelling at a fine spatial scale.

    Science.gov (United States)

    Muška, Milan; Tušer, Michal; Frouzová, Jaroslava; Mrkvička, Tomáš; Ricard, Daniel; Seďa, Jaromír; Morelli, Federico; Kubečka, Jan

    2018-03-29

    Understanding spatial distribution of organisms in heterogeneous environment remains one of the chief issues in ecology. Spatial organization of freshwater fish was investigated predominantly on large-scale, neglecting important local conditions and ecological processes. However, small-scale processes are of an essential importance for individual habitat preferences and hence structuring trophic cascades and species coexistence. In this work, we analysed the real-time spatial distribution of pelagic freshwater fish in the Římov Reservoir (Czechia) observed by hydroacoustics in relation to important environmental predictors during 48 hours at 3-h interval. Effect of diurnal cycle was revealed of highest significance in all spatial models with inverse trends between fish distribution and predictors in day and night in general. Our findings highlighted daytime pelagic fish distribution as highly aggregated, with general fish preferences for central, deep and highly illuminated areas, whereas nighttime distribution was more disperse and fish preferred nearshore steep sloped areas with higher depth. This turnover suggests prominent movements of significant part of fish assemblage between pelagic and nearshore areas on a diel basis. In conclusion, hydroacoustics, GIS and spatial modelling proved as valuable tool for predicting local fish distribution and elucidate its drivers, which has far reaching implications for understanding freshwater ecosystem functioning.

  13. Real time falling leaves

    OpenAIRE

    Vázquez Alcocer, Pere Pau; Balsa, Marcos

    2007-01-01

    There is a growing interest in simulating natural phenomena in computer graphics applications. Animating natural scenes in real time is one of the most challenging problems due to the inherent complexity of their structure, formed by millions of geometric entities, and the interactions that happen within. An example of natural scenario that is needed for games or simulation programs are forests. Forests are difficult to render because the huge amount of geometric entities and the large amount...

  14. OST: analysis tool for real time software by simulation of material and software environments

    International Nuclear Information System (INIS)

    Boulc'h; Le Meur; Lapassat; Salichon; Segalard

    1988-07-01

    The utilization of microprocessors systems in a nuclear installation control oblige a great operation safety in the installation operation and in the environment protection. For the safety analysis of these installations the Institute of Protection and Nuclear Safety (IPSN) will dispose tools which permit to make controls during all the life of the software. The simulation and test tool (OST) which have been created is completely made by softwares. It is used on VAX calculators and can be easily transportable on other calculators [fr

  15. Real-time SWMF-Geospace at CCMC: assessing the quality of output from continuous operational simulations

    Science.gov (United States)

    Liemohn, M. W.; Welling, D. T.; De Zeeuw, D.; Kuznetsova, M. M.; Rastaetter, L.; Ganushkina, N. Y.; Ilie, R.; Toth, G.; Gombosi, T. I.; van der Holst, B.

    2016-12-01

    The ground-based magnetometer index Dst is a decent measure of the near-Earth current systems, in particular those in the storm-time inner magnetosphere. The ability of a large-scale, physics-based model to reproduce, or even predict, this index is therefore a tangible measure of the overall validity of the code for space weather research and space weather operational usage. Experimental real-time simulations of the Space Weather Modeling Framework (SWMF) are conducted at the Community Coordinated Modeling Center (CCMC), with results available there (http://ccmc.gsfc.nasa.gov/realtime.php), through the CCMC Integrated Space Weather Analysis (iSWA) site (http://iswa.ccmc.gsfc.nasa.gov/IswaSystemWebApp/), and the Michigan SWMF site (http://csem.engin.umich.edu/realtime). Presently, two configurations of the SWMF are running in real time at CCMC, both focusing on the geospace modules, using the BATS-R-US magnetohydrodynamic model, the Ridley Ionosphere Model, and with and without the Rice Convection Model for inner magnetospheric drift physics. While both have been running for several years, nearly continuous results are available since July 2015. Dst from the model output is compared against the Kyoto real-time Dst. Various quantitative measures are presented to assess the goodness of fit between the models and observations. In particular, correlation coefficients, RMSE and prediction efficiency are calculated and discussed. In addition, contingency tables are presented, demonstrating the ability of the model to predict "disturbed times" as defined by Dst values below some critical threshold. It is shown that the SWMF run with the inner magnetosphere model is significantly better at reproducing storm-time values, with prediction efficiencies above 0.25 and Heidke skill scores above 0.5. This work was funded by NASA and NSF grants, and the European Union's Horizon 2020 research and innovation programme under grant agreement 637302 PROGRESS.

  16. Extending the range of real time density matrix renormalization group simulations

    Science.gov (United States)

    Kennes, D. M.; Karrasch, C.

    2016-03-01

    We discuss a few simple modifications to time-dependent density matrix renormalization group (DMRG) algorithms which allow to access larger time scales. We specifically aim at beginners and present practical aspects of how to implement these modifications within any standard matrix product state (MPS) based formulation of the method. Most importantly, we show how to 'combine' the Schrödinger and Heisenberg time evolutions of arbitrary pure states | ψ 〉 and operators A in the evaluation of 〈A〉ψ(t) = 〈 ψ | A(t) | ψ 〉 . This includes quantum quenches. The generalization to (non-)thermal mixed state dynamics 〈A〉ρ(t) =Tr [ ρA(t) ] induced by an initial density matrix ρ is straightforward. In the context of linear response (ground state or finite temperature T > 0) correlation functions, one can extend the simulation time by a factor of two by 'exploiting time translation invariance', which is efficiently implementable within MPS DMRG. We present a simple analytic argument for why a recently-introduced disentangler succeeds in reducing the effort of time-dependent simulations at T > 0. Finally, we advocate the python programming language as an elegant option for beginners to set up a DMRG code.

  17. Real-time simulation of E-motors; Echtzeitsimulation von E-Motoren

    Energy Technology Data Exchange (ETDEWEB)

    Ploeger, Markus; Deter, Matthias [dSpace GmbH, Paderborn (Germany)

    2013-05-15

    The electric drive motor is a central component in many modern drive concepts. In hybrid vehicles and also in pure electric vehicles, controlling and regulating these motors is a major factor in achieving development goals regarding efficiency, emission reduction and vehicle dynamics. As an additional component in the drivetrain with significantly increased dynamics in comparison to internal combustion engines, the electric motor is posing new challenges for development engineers and development tools. This also affects hardware-in-the-loop (HiL) simulation, which is now an established step in the development of automotive electronic control units. The company dSpace describes some of these challenges and presents possible solutions showing what HiL test benches for electric motors could look like. (orig.)

  18. Impact of real-time measurements for data assimilation in reservoir simulation

    Energy Technology Data Exchange (ETDEWEB)

    Schulze-Riegert, R; Krosche, M [Scandpower Petroleum Technology GmbH, Hamburg (Germany); Pajonk, O [TU Braunschweig (Germany). Inst. fuer Wissenschaftliches Rechnen; Myrland, T [Morges Teknisk-Naturvitenskapelige Univ. (NTNU), Trondheim (Germany)

    2008-10-23

    This paper gives an overview on the conceptual background of data assimilation techniques. The framework of sequential data assimilation as described for the ensemble Kalman filter implementation allows a continuous integration of new measurement data. The initial diversity of ensemble members will be critical for the assimilation process and the ability to successfully assimilate measurement data. At the same time the initial ensemble will impact the propagation of uncertainties with crucial consequences for production forecasts. Data assimilation techniques have complimentary features compared to other optimization techniques built on selection or regression schemes. Specifically, EnKF is applicable to real field cases and defines an important perspective for facilitating continuous reservoir simulation model updates in a reservoir life cycle. (orig.)

  19. Practical performance of real-time shot-noise measurement in continuous-variable quantum key distribution

    Science.gov (United States)

    Wang, Tao; Huang, Peng; Zhou, Yingming; Liu, Weiqi; Zeng, Guihua

    2018-01-01

    In a practical continuous-variable quantum key distribution (CVQKD) system, real-time shot-noise measurement (RTSNM) is an essential procedure for preventing the eavesdropper exploiting the practical security loopholes. However, the performance of this procedure itself is not analyzed under the real-world condition. Therefore, we indicate the RTSNM practical performance and investigate its effects on the CVQKD system. In particular, due to the finite-size effect, the shot-noise measurement at the receiver's side may decrease the precision of parameter estimation and consequently result in a tight security bound. To mitigate that, we optimize the block size for RTSNM under the ensemble size limitation to maximize the secure key rate. Moreover, the effect of finite dynamics of amplitude modulator in this scheme is studied and its mitigation method is also proposed. Our work indicates the practical performance of RTSNM and provides the real secret key rate under it.

  20. A distributed real-time system for event-driven control and dynamic data acquisition on a fusion plasma experiment

    International Nuclear Information System (INIS)

    Sousa, J.; Combo, A.; Batista, A.; Correia, M.; Trotman, D.; Waterhouse, J.; Varandas, C.A.F.

    2000-01-01

    A distributed real-time trigger and timing system, designed in a tree-type topology and implemented in VME and CAMAC versions, has been developed for a magnetic confinement fusion experiment. It provides sub-microsecond time latencies for the transport of small data objects allowing event-driven discharge control with failure counteraction, dynamic pre-trigger sampling and event recording as well as accurate simultaneous triggers and synchronism on all nodes with acceptable optimality and predictability of timeliness. This paper describes the technical characteristics of the hardware components (central unit composed by one or more reflector crates, event and synchronism reflector cards, event and pulse node module, fan-out and fan-in modules) as well as software for both tests and integration on a global data acquisition system. The results of laboratory operation for several configurations and the overall performance of the system are presented and analysed

  1. Feasibility Study of the Electromagnetic Damper for Cable Structures Using Real-Time Hybrid Simulation.

    Science.gov (United States)

    Jung, Ho-Yeon; Kim, In-Ho; Jung, Hyung-Jo

    2017-10-31

    Cable structure is a major component of long-span bridges, such as cable-stayed and suspension bridges, and it transfers the main loads of bridges to the pylons. As these cable structures are exposed to continuous external loads, such as vehicle and wind loads, vibration control and continuous monitoring of the cable are required. In this study, an electromagnetic (EM) damper was designed and fabricated for vibration control and monitoring of the cable structure. EM dampers, also called regenerative dampers, consist of permanent magnets and coils. The electromagnetic force due to the relative motion between the coil and the permanent magnet can be used to control the vibration of the structure. The electrical energy can be used as a power source for the monitoring system. The effects of the design parameters of the damper were numerically analyzed and the damper was fabricated. The characteristics of the damper were analyzed with various external load changes. Finally, the vibration-control and energy-harvesting performances of the cable structure were evaluated through a hybrid simulation. The vibration-control and energy-harvesting performances for various loads were analyzed and the applicability to the cable structure of the EM damper was evaluated.

  2. CAMS as a tool for identifying and predicting abnormal plant states using real-time simulation

    International Nuclear Information System (INIS)

    Fantoni, P.F.; Soerenssen, A.; Meyer, G.

    1999-01-01

    CAMS (Computerised Accident Management Support) is a system that provides assistance to the staff in a nuclear power plant control room, in the technical support centre and in the national safety centre. Support is offered in identification of the current plant state, in assessment of the future development of the accident and in planning mitigation strategies. CAMS is a modular system, where several modules perform different tasks under the control and supervision of a central knowledge based system, which is responsible of the syncronisation and the flow of information through the activated modules. A CAMS prototype has been tested by the Swedish Nuclear Inspectorate during a safety exercise in Sweden in 1995, with satisfactory results. Future developments include automatic control of the Predictive Simulator by the State Identification, for the generation of possible mitigation strategies, and the development of an improved user interface which considers the integration of the system in an advanced control room. CAMS is a system developed as a joint research activity at the Halden Reactor Project in close cooperation with member organisations. The project, started in 1993, has now arrived to the second prototype version, which has been presented and demonstrated at several seminars and workshops around the world. (author)

  3. Feasibility Study of the Electromagnetic Damper for Cable Structures Using Real-Time Hybrid Simulation

    Directory of Open Access Journals (Sweden)

    Ho-Yeon Jung

    2017-10-01

    Full Text Available Cable structure is a major component of long-span bridges, such as cable-stayed and suspension bridges, and it transfers the main loads of bridges to the pylons. As these cable structures are exposed to continuous external loads, such as vehicle and wind loads, vibration control and continuous monitoring of the cable are required. In this study, an electromagnetic (EM damper was designed and fabricated for vibration control and monitoring of the cable structure. EM dampers, also called regenerative dampers, consist of permanent magnets and coils. The electromagnetic force due to the relative motion between the coil and the permanent magnet can be used to control the vibration of the structure. The electrical energy can be used as a power source for the monitoring system. The effects of the design parameters of the damper were numerically analyzed and the damper was fabricated. The characteristics of the damper were analyzed with various external load changes. Finally, the vibration-control and energy-harvesting performances of the cable structure were evaluated through a hybrid simulation. The vibration-control and energy-harvesting performances for various loads were analyzed and the applicability to the cable structure of the EM damper was evaluated.

  4. Real-time image-based B-mode ultrasound image simulation of needles using tensor-product interpolation.

    Science.gov (United States)

    Zhu, Mengchen; Salcudean, Septimiu E

    2011-07-01

    In this paper, we propose an interpolation-based method for simulating rigid needles in B-mode ultrasound images in real time. We parameterize the needle B-mode image as a function of needle position and orientation. We collect needle images under various spatial configurations in a water-tank using a needle guidance robot. Then we use multidimensional tensor-product interpolation to simulate images of needles with arbitrary poses and positions using collected images. After further processing, the interpolated needle and seed images are superimposed on top of phantom or tissue image backgrounds. The similarity between the simulated and the real images is measured using a correlation metric. A comparison is also performed with in vivo images obtained during prostate brachytherapy. Our results, carried out for both the convex (transverse plane) and linear (sagittal/para-sagittal plane) arrays of a trans-rectal transducer indicate that our interpolation method produces good results while requiring modest computing resources. The needle simulation method we present can be extended to the simulation of ultrasound images of other wire-like objects. In particular, we have shown that the proposed approach can be used to simulate brachytherapy seeds.

  5. Effects of Self-Instructional Methods and Above Real Time Training (ARTT) for Maneuvering Tasks on a Flight Simulator

    Science.gov (United States)

    Ali, Syed Firasat; Khan, Javed Khan; Rossi, Marcia J.; Crane, Peter; Heath, Bruce E.; Knighten, Tremaine; Culpepper, Christi

    2003-01-01

    Personal computer based flight simulators are expanding opportunities for providing low-cost pilot training. One advantage of these devices is the opportunity to incorporate instructional features into training scenarios that might not be cost effective with earlier systems. Research was conducted to evaluate the utility of different instructional features using a coordinated level turn as an aircraft maneuvering task. In study I, a comparison was made between automated computer grades of performance with certified flight instructors grades. Every one of the six student volunteers conducted a flight with level turns at two different bank angles. The automated computer grades were based on prescribed tolerances on bank angle, airspeed and altitude. Two certified flight instructors independently examined the video tapes of heads up and instrument displays of the flights and graded them. The comparison of automated grades with the instructors grades was based on correlations between them. In study II, a 2x2 between subjects factorial design was used to devise and conduct an experiment. Comparison was made between real time training and above real time training and between feedback and no feedback in training. The performance measure to monitor progress in training was based on deviations in bank angle and altitude. The performance measure was developed after completion of the experiment including the training and test flights. It was not envisaged before the experiment. The experiment did not include self- instructions as it was originally planned, although feedback by experimenter to the trainee was included in the study.

  6. Performance of overlapped shield tunneling through an integrated physical model tests, numerical simulations and real-time field monitoring

    Directory of Open Access Journals (Sweden)

    Junlong Yang

    2017-03-01

    Full Text Available In this work, deformations and internal forces of an existing tunnel subjected to a closely overlapped shield tunneling are monitored and analyzed using a series of physical model experiments and numerical simulations. Effects of different excavation sequences and speeds are explicitly considered in the analysis. The results of the physical model experiments show that the bottom-up tunneling procedure is better than the top-down tunneling procedure. The incurred deformations and internal forces of the existing tunnel increase with the excavation speed and the range of influence areas also increase accordingly. For construction process control, real-time monitoring of the power tunnel is used. The monitoring processes feature full automation, adjustable frequency, real-time monitor and dynamic feedback, which are used to guide the construction to achieve micro-disturbance control. In accordance with the situation of crossing construction, a numerical study on the performance of power tunnel is carried out. Construction control measures are given for the undercrossing construction, which helps to accomplish the desired result and meet protection requirements of the existing tunnel structure. Finally, monitoring data and numerical results are compared, and the displacement and joint fracture change models in the power tunnel subject to the overlapped shield tunnel construction are analyzed. Keywords: Overlapped tunnel, Automatic monitoring, Micro-disturbance control

  7. Real-time simulation of soft tissue deformation and electrocautery procedures in laparoscopic rectal cancer radical surgery.

    Science.gov (United States)

    Sui, Yuan; Pan, Jun J; Qin, Hong; Liu, Hao; Lu, Yun

    2017-12-01

    Laparoscopic surgery (LS), also referred to as minimally invasive surgery, is a modern surgical technique which is widely applied. The fulcrum effect makes LS a non-intuitive motor skill with a steep learning curve. A hybrid model of tetrahedrons and a multi-layer triangular mesh are constructed to simulate the deformable behavior of the rectum and surrounding tissues in the Position-Based Dynamics (PBD) framework. A heat-conduction based electric-burn technique is employed to simulate the electrocautery procedure. The simulator has been applied for laparoscopic rectum cancer surgery training. From the experimental results, trainees can operate in real time with high degrees of stability and fidelity. A preliminary study was performed to evaluate the realism and usefulness. This prototype simulator has been tested and verified by colorectal surgeons through a pilot study. They believed both the visual and the haptic performance of the simulation are realistic and helpful to enhance laparoscopic skills. Copyright © 2017 John Wiley & Sons, Ltd.

  8. Network Dynamics with BrainX3: A Large-Scale Simulation of the Human Brain Network with Real-Time Interaction

    OpenAIRE

    Xerxes D. Arsiwalla; Riccardo eZucca; Alberto eBetella; Enrique eMartinez; David eDalmazzo; Pedro eOmedas; Gustavo eDeco; Gustavo eDeco; Paul F.M.J. Verschure; Paul F.M.J. Verschure

    2015-01-01

    BrainX3 is a large-scale simulation of human brain activity with real-time interaction, rendered in 3D in a virtual reality environment, which combines computational power with human intuition for the exploration and analysis of complex dynamical networks. We ground this simulation on structural connectivity obtained from diffusion spectrum imaging data and model it on neuronal population dynamics. Users can interact with BrainX3 in real-time by perturbing brain regions with transient stimula...

  9. Network dynamics with BrainX3: a large-scale simulation of the human brain network with real-time interaction

    OpenAIRE

    Arsiwalla, Xerxes D.; Zucca, Riccardo; Betella, Alberto; Martínez, Enrique, 1961-; Dalmazzo, David; Omedas, Pedro; Deco, Gustavo; Verschure, Paul F. M. J.

    2015-01-01

    BrainX3 is a large-scale simulation of human brain activity with real-time interaction, rendered in 3D in a virtual reality environment, which combines computational power with human intuition for the exploration and analysis of complex dynamical networks. We ground this simulation on structural connectivity obtained from diffusion spectrum imaging data and model it on neuronal population dynamics. Users can interact with BrainX3 in real-time by perturbing brain regions with transient stimula...

  10. Real-time appraisal of the spatially distributed heat related health risk and energy demand of cities

    Science.gov (United States)

    Keramitsoglou, Iphigenia; Kiranoudis, Chris T.; Sismanidis, Panagiotis

    2016-08-01

    The Urban Heat Island (UHI) is an adverse environmental effect of urbanization that increases the energy demand of cities, impacts the human health, and intensifies and prolongs heatwave events. To facilitate the study of UHIs the Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing of the National Observatory of Athens (IAASARS/NOA) has developed an operational real-time system that exploits remote sensing image data from Meteosat Second Generation - Spinning Enhanced Visible and Infrared Imager (MSG-SEVIRI) and generates high spatiotemporal land surface temperature (LST) and 2 m air temperature (TA) time series. These datasets form the basis for the generation of higher value products and services related to energy demand and heat-related health issues. These products are the heatwave hazard (HZ); the HUMIDEX (i.e. an index that describes the temperature felt by an individual exposed to heat and humidity); and the cooling degrees (CD; i.e. a measure that reflects the energy needed to cool a building). The spatiotemporal characteristics of HZ, HUMIDEX and CD are unique (1 km/5 min) and enable the appraisal of the spatially distributed heat related health risk and energy demand of cities. In this paper, the real time generation of the high spatiotemporal HZ, HUMIDEX and CD products is discussed. In addition, a case study corresponding to Athens' September 2015 heatwave is presented so as to demonstrate their capabilities. The overall aim of the system is to provide high quality data to several different end users, such as health responders, and energy suppliers. The urban thermal monitoring web service is available at http://snf-652558.vm.okeanos.grnet.gr/treasure/portal/info.html.

  11. Real-time UV imaging of piroxicam diffusion and distribution from oil solutions into gels mimicking the subcutaneous matrix.

    Science.gov (United States)

    Ye, Fengbin; Larsen, Susan Weng; Yaghmur, Anan; Jensen, Henrik; Larsen, Claus; Østergaard, Jesper

    2012-05-12

    A novel real-time UV imaging approach for non-intrusive investigation of the diffusion and partitioning phenomena occurring during piroxicam release from medium chain triglyceride (MCT) solution into two hydrogel matrices is described. Two binary polymer/buffer gel matrices, 0.5% (w/v) agarose and 25% (w/v) Pluronic F127, were applied as simple models mimicking the subcutaneous tissue. The evolution of the absorbance maps as a function of time provided detailed information on the piroxicam release processes upon the exposure of the gel matrices to MCT. Using calibration curves, the concentration maps of piroxicam in the UV imaging area were determined. Regression of the longitudinal concentration-distance profiles, which were obtained using expressions derived from Fick's second law, provided the diffusivity and the distribution coefficients of piroxicam penetrated into the gels. The obtained MCT-agarose (pH 7.4) distribution coefficient of 1.4 was identical to the MCT-aqueous (pH 7.4) distribution coefficient determined by the shake-flask method whereas that of the MCT-Pluronic F127 system was four times less. The experimental data show that UV imaging may have considerable potential for investigating the transport properties of drug formulations intended for the subcutaneous administration. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. Real-time ArcGIS and heterotrophic plate count based chloramine disinfectant control in water distribution system.

    Science.gov (United States)

    Bai, Xiaohui; Zhi, Xinghua; Zhu, Huifeng; Meng, Mingqun; Zhang, Mingde

    2015-01-01

    This study investigates the effect of chloramine residual on bacteria growth and regrowth and the relationship between heterotrophic plate counts (HPCs) and the concentration of chloramine residual in the Shanghai drinking water distribution system (DWDS). In this study, models to control HPCs in the water distribution system and consumer taps are also developed. Real-time ArcGIS was applied to show the distribution and changed results of the chloramine residual concentration in the pipe system by using these models. Residual regression analysis was used to get a reasonable range of the threshold values that allows the chloramine residual to efficiently inhibit bacteria growth in the Shanghai DWDS; the threshold values should be between 0.45 and 0.5 mg/L in pipe water and 0.2 and 0.25 mg/L in tap water. The low residual chloramine value (0.05 mg/L) of the Chinese drinking water quality standard may pose a potential health risk for microorganisms that should be improved. Disinfection by-products (DBPs) were detected, but no health risk was identified.

  13. Passive hybrid force-position control for tele-operation based on real-time simulation of a virtual mechanism

    International Nuclear Information System (INIS)

    Joly, L.; Andriot, C.

    1995-01-01

    Hybrid force-position control aims at controlling position and force in separate directions. It is particularly useful to perform certain robotic tasks. In tele-operation context, passivity is important because it ensures stability when the system interacts with any passive environment. In this paper, we propose an original approach to hybrid force-position control of a force reflecting tele-robot system. It is based on real-time simulation of a virtual mechanism corresponding to the task. the resulting control law is passive. Experiments on a 6 degrees of freedom tele-operation system consisting in following a bent pipe under several control modes validate the approach. (authors). 12 refs., 6 figs

  14. Impact of Real-Time Image Gating on Spot Scanning Proton Therapy for Lung Tumors: A Simulation Study

    Energy Technology Data Exchange (ETDEWEB)

    Kanehira, Takahiro [Department of Radiation Medicine, Graduate School of Medicine, Hokkaido University, Sapporo (Japan); Matsuura, Taeko, E-mail: matsuura@med.hokudai.ac.jp [Proton Beam Therapy Center, Hokkaido University Hospital, Sapporo (Japan); Global Station for Quantum Medical Science and Engineering, Global Institution for Collaborative Research and Education, Hokkaido University, Sapporo (Japan); Division of Quantum Science and Engineering, Faculty of Engineering, Hokkaido University, Sapporo (Japan); Takao, Seishin; Matsuzaki, Yuka; Fujii, Yusuke; Fujii, Takaaki [Proton Beam Therapy Center, Hokkaido University Hospital, Sapporo (Japan); Ito, Yoichi M. [Department of Biostatistics, Hokkaido University Graduate School of Medicine, Sapporo (Japan); Miyamoto, Naoki [Department of Medical Physics, Hokkaido University Hospital, Sapporo (Japan); Inoue, Tetsuya [Department of Radiation Medicine, Graduate School of Medicine, Hokkaido University, Sapporo (Japan); Katoh, Norio [Department of Radiation Oncology, Hokkaido University Hospital, Sapporo (Japan); Shimizu, Shinichi [Global Station for Quantum Medical Science and Engineering, Global Institution for Collaborative Research and Education, Hokkaido University, Sapporo (Japan); Department of Radiation Oncology, Graduate School of Medicine, Hokkaido University, Sapporo (Japan); Umegaki, Kikuo [Proton Beam Therapy Center, Hokkaido University Hospital, Sapporo (Japan); Division of Quantum Science and Engineering, Faculty of Engineering, Hokkaido University, Sapporo (Japan); Shirato, Hiroki [Department of Radiation Medicine, Graduate School of Medicine, Hokkaido University, Sapporo (Japan); Global Station for Quantum Medical Science and Engineering, Global Institution for Collaborative Research and Education, Hokkaido University, Sapporo (Japan)

    2017-01-01

    Purpose: To investigate the effectiveness of real-time-image gated proton beam therapy for lung tumors and to establish a suitable size for the gating window (GW). Methods and Materials: A proton beam gated by a fiducial marker entering a preassigned GW (as monitored by 2 fluoroscopy units) was used with 7 lung cancer patients. Seven treatment plans were generated: real-time-image gated proton beam therapy with GW sizes of ±1, 2, 3, 4, 5, and 8 mm and free-breathing proton therapy. The prescribed dose was 70 Gy (relative biological effectiveness)/10 fractions to 99% of the target. Each of the 3-dimensional marker positions in the time series was associated with the appropriate 4-dimensional computed tomography phase. The 4-dimensional dose calculations were performed. The dose distribution in each respiratory phase was deformed into the end-exhale computed tomography image. The D99 and D5 to D95 of the clinical target volume scaled by the prescribed dose with criteria of D99 >95% and D5 to D95 <5%, V20 for the normal lung, and treatment times were evaluated. Results: Gating windows ≤ ±2 mm fulfilled the CTV criteria for all patients (whereas the criteria were not always met for GWs ≥ ±3 mm) and gave an average reduction in V20 of more than 17.2% relative to free-breathing proton therapy (whereas GWs ≥ ±4 mm resulted in similar or increased V20). The average (maximum) irradiation times were 384 seconds (818 seconds) for the ±1-mm GW, but less than 226 seconds (292 seconds) for the ±2-mm GW. The maximum increased considerably at ±1-mm GW. Conclusion: Real-time-image gated proton beam therapy with a GW of ±2 mm was demonstrated to be suitable, providing good dose distribution without greatly extending treatment time.

  15. Impact of Real-Time Image Gating on Spot Scanning Proton Therapy for Lung Tumors: A Simulation Study.

    Science.gov (United States)

    Kanehira, Takahiro; Matsuura, Taeko; Takao, Seishin; Matsuzaki, Yuka; Fujii, Yusuke; Fujii, Takaaki; Ito, Yoichi M; Miyamoto, Naoki; Inoue, Tetsuya; Katoh, Norio; Shimizu, Shinichi; Umegaki, Kikuo; Shirato, Hiroki

    2017-01-01

    To investigate the effectiveness of real-time-image gated proton beam therapy for lung tumors and to establish a suitable size for the gating window (GW). A proton beam gated by a fiducial marker entering a preassigned GW (as monitored by 2 fluoroscopy units) was used with 7 lung cancer patients. Seven treatment plans were generated: real-time-image gated proton beam therapy with GW sizes of ±1, 2, 3, 4, 5, and 8 mm and free-breathing proton therapy. The prescribed dose was 70 Gy (relative biological effectiveness)/10 fractions to 99% of the target. Each of the 3-dimensional marker positions in the time series was associated with the appropriate 4-dimensional computed tomography phase. The 4-dimensional dose calculations were performed. The dose distribution in each respiratory phase was deformed into the end-exhale computed tomography image. The D99 and D5 to D95 of the clinical target volume scaled by the prescribed dose with criteria of D99 >95% and D5 to D95 lung, and treatment times were evaluated. Gating windows ≤ ±2 mm fulfilled the CTV criteria for all patients (whereas the criteria were not always met for GWs ≥ ±3 mm) and gave an average reduction in V20 of more than 17.2% relative to free-breathing proton therapy (whereas GWs ≥ ±4 mm resulted in similar or increased V20). The average (maximum) irradiation times were 384 seconds (818 seconds) for the ±1-mm GW, but less than 226 seconds (292 seconds) for the ±2-mm GW. The maximum increased considerably at ±1-mm GW. Real-time-image gated proton beam therapy with a GW of ±2 mm was demonstrated to be suitable, providing good dose distribution without greatly extending treatment time. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Real-time surgery simulation of intracranial aneurysm clipping with patient-specific geometries and haptic feedback

    Science.gov (United States)

    Fenz, Wolfgang; Dirnberger, Johannes

    2015-03-01

    Providing suitable training for aspiring neurosurgeons is becoming more and more problematic. The increasing popularity of the endovascular treatment of intracranial aneurysms leads to a lack of simple surgical situations for clipping operations, leaving mainly the complex cases, which present even experienced surgeons with a challenge. To alleviate this situation, we have developed a training simulator with haptic interaction allowing trainees to practice virtual clipping surgeries on real patient-specific vessel geometries. By using specialized finite element (FEM) algorithms (fast finite element method, matrix condensation) combined with GPU acceleration, we can achieve the necessary frame rate for smooth real-time interaction with the detailed models needed for a realistic simulation of the vessel wall deformation caused by the clamping with surgical clips. Vessel wall geometries for typical training scenarios were obtained from 3D-reconstructed medical image data, while for the instruments (clipping forceps, various types of clips, suction tubes) we use models provided by manufacturer Aesculap AG. Collisions between vessel and instruments have to be continuously detected and transformed into corresponding boundary conditions and feedback forces, calculated using a contact plane method. After a training, the achieved result can be assessed based on various criteria, including a simulation of the residual blood flow into the aneurysm. Rigid models of the surgical access and surrounding brain tissue, plus coupling a real forceps to the haptic input device further increase the realism of the simulation.

  17. Interactive Real-time Simulation of a Nuclear Reactor Emergency Core Cooling System on a Desktop Computer

    International Nuclear Information System (INIS)

    Muncharoen, C.; Chanyotha, S.; Bereznai, G.

    1998-01-01

    The simulation of the Emergency Core Cooling System for a 900 MW nuclear power plant has been developed by using object oriented programming language. It is capable of generating code that executes in real-time on a PENTIUM 100 or equivalent personal computer. Graphical user interface ECCS screens have been developed using Lab VIEW to allow interactive control of ECCS. The usual simulator functions, such as freeze, run, iterate, have been provided, and a number of malfunctions may be activated. A large pipe break near the reactor inlet header has been simulated to verify the response of the ECCS model. LOCA detection, ECC initiation, injection and recovery phased are all modeled, and give results consistent with safety analysis data for a 100% break. With stand alone ECCS simulation, the changes of flow and pressure in ECCS can be observed. The operator can study operational procedures and get used to LOCA in case of the LOCA. Practicing with malfunction, the operator will improve problem solving skills and gain a deeper comprehension of ECCS

  18. A physics-based algorithm for real-time simulation of electrosurgery procedures in minimally invasive surgery.

    Science.gov (United States)

    Lu, Zhonghua; Arikatla, Venkata S; Han, Zhongqing; Allen, Brian F; De, Suvranu

    2014-12-01

    High-frequency electricity is used in the majority of surgical interventions. However, modern computer-based training and simulation systems rely on physically unrealistic models that fail to capture the interplay of the electrical, mechanical and thermal properties of biological tissue. We present a real-time and physically realistic simulation of electrosurgery by modelling the electrical, thermal and mechanical properties as three iteratively solved finite element models. To provide subfinite-element graphical rendering of vaporized tissue, a dual-mesh dynamic triangulation algorithm based on isotherms is proposed. The block compressed row storage (BCRS) structure is shown to be critical in allowing computationally efficient changes in the tissue topology due to vaporization. We have demonstrated our physics-based electrosurgery cutting algorithm through various examples. Our matrix manipulation algorithms designed for topology changes have shown low computational cost. Our simulator offers substantially greater physical fidelity compared to previous simulators that use simple geometry-based heat characterization. Copyright © 2013 John Wiley & Sons, Ltd.

  19. Real-time adjustment of pressure to demand in water distribution systems: Parameter-less P-controller algorithm

    CSIR Research Space (South Africa)

    Page, Philip R

    2016-08-01

    Full Text Available Remote real-time control is currently the most advanced form of pressure management. Here the parameters describing pressure control valves (or pumps) are changed in real-time in such a way to provide the most optimal pressure in the water...

  20. Making the Grid "Smart" Through "Smart" Microgrids: Real-Time Power Management of Microgrids with Multiple Distributed Generation Sources Using Intelligent Control

    Energy Technology Data Exchange (ETDEWEB)

    Nehrir, M. Hashem [Montana State Univ., Bozeman, MT (United States)

    2016-10-20

    In this Project we collaborated with two DOE National Laboratories, Pacific Northwest National Lab (PNNL) and Lawrence Berkeley National Lab (LBL). Dr. Hammerstrom of PNNL initially supported our project and was on the graduate committee of one of the Ph.D. students (graduated in 2014) who was supported by this project. He is also a committee member of a current graduate student of the PI who was supported by this project in the last two years (August 2014-July 2016). The graduate student is now supported be the Electrical and Computer Engineering (ECE) Department at Montana State University (MSU). Dr. Chris Marney of LBL provided actual load data, and the software WEBOPT developed at LBL for microgrid (MG) design for our project. NEC-Labs America, a private industry, also supported our project, providing expert support and modest financial support. We also used the software “HOMER,” originally developed at the National Renewable Energy Laboratory (NREL) and the most recent version made available to us by HOMER Energy, Inc., for MG (hybrid energy system) unit sizing. We compared the findings from WebOpt and HOMER and designed appropriately sized hybrid systems for our case studies. The objective of the project was to investigate real-time power management strategies for MGs using intelligent control, considering maximum feasible energy sustainability, reliability and efficiency while, minimizing cost and undesired environmental impact (emissions). Through analytic and simulation studies, we evaluated the suitability of several heuristic and artificial-intelligence (AI)-based optimization techniques that had potential for real-time MG power management, including genetic algorithms (GA), ant colony optimization (ACO), particle swarm optimization (PSO), and multi-agent systems (MAS), which is based on the negotiation of smart software-based agents. We found that PSO and MAS, in particular, distributed MAS, were more efficient and better suited for our work. We

  1. An IP-Based Software System for Real-time, Closed Loop, Multi-Spacecraft Mission Simulations

    Science.gov (United States)

    Cary, Everett; Davis, George; Higinbotham, John; Burns, Richard; Hogie, Keith; Hallahan, Francis

    2003-01-01

    This viewgraph presentation provides information on the architecture of a computerized testbest for simulating Distributed Space Systems (DSS) for controlling spacecraft flying in formation. The presentation also discusses and diagrams the Distributed Synthesis Environment (DSE) for simulating and planning DSS missions.

  2. Some contributions towards the parallel simulation of time dependent neutron transport and the integration of observed data in real time

    International Nuclear Information System (INIS)

    Mula-Hernandez, Olga

    2014-01-01

    In this thesis, we have first developed a time dependent 3D neutron transport solver on unstructured meshes with discontinuous Galerkin finite elements spatial discretization. The solver (called MINARET) represents in itself an important contribution in reactor physics thanks to the accuracy that it can provide in the knowledge of the state of the core during severe accidents. It will also play an important role on vessel fluence calculations. From a mathematical point of view, the most important contribution has consisted in the implementation of modern algorithms that are well adapted for modern parallel architectures and that significantly decrease the computing times. A special effort has been done in order to efficiently parallelize the time variable by the use of the parareal in time algorithm. For this, we have first analyzed the performances that the classical scheme of parareal can provide when applied to the resolution of the neutron transport equation in a reactor core. Then, with the purpose of improving these performances, a parareal scheme that takes more efficiently into account the presence of other iterative schemes in the resolution of each time step has been proposed. The main idea consists in limiting the number of internal iterations for each time step and to reach convergence across the parareal iterations. A second phase of our work has been motivated by the following question: given the high degree of accuracy that MINARET can provide in the modeling of the neutron population, could we somehow use it as a tool to monitor in real time the population of neutrons on the purpose of helping in the operation of the reactor? And, what is more, how to make such a tool be coherent in some sense with the measurements taken in situ? One of the main challenges of this problem is the real time aspect of the simulations. Indeed, despite all of our efforts to speed-up the calculations, the discretization methods used in MINARET do not provide simulations

  3. Analysis of lightning fault detection, location and protection on short and long transmission lines using Real Time Digital Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Andre Luiz Pereira de [Siemens Ltda., Sao Paulo, SP (Brazil)], E-mail: andreluiz.oliveira@siemens.com

    2007-07-01

    The purpose of this paper is to present an analysis of lightning fault detection, location and protection using numeric distance relays applied in high voltage transmission lines, more specifically in the 500 kV transmission lines of CEMIG (Brazilian Energy Utility) between the Vespasiano 2 - Neves 1 (short line - 23.9 km) and Vespasiano 2 - Mesquita (long line - 148.6 km) substations. The analysis was based on the simulations results of numeric distance protective relays on power transmission lines, realized in September 02 to 06, 2002, at Siemens AG's facilities (Erlangen - Germany), using Real Time Digital Simulator (RTDS{sup TM}). Several lightning faults simulations were accomplished, in several conditions of the electrical power system where the protective relays would be installed. The results are presented not only with the times of lightning faults elimination, but also all the functionality of a protection system, including the correct detection, location and other advantages that these modern protection devices make possible to the power system. (author)

  4. Energy Resources Intelligent Management using on line real-time simulation: A decision support tool for sustainable manufacturing

    International Nuclear Information System (INIS)

    Cassettari, Lucia; Bendato, Ilaria; Mosca, Marco; Mosca, Roberto

    2017-01-01

    Highlights: • A new way to manage the self production of energy from RES in manufacturing industry. • Optimization in terms of both energy costs and environmental impact (CO_2 emissions). • The use of on-line real-time Discrete Event Simulation to manage the stochasticity. • The energy production plan is dynamically suited to weather and manufacturing needs. • The test case presented highlights the effectiveness of the proposed methodology. - Abstract: At a historic time when the eco-sustainability of industrial manufacturing is considered one of the cornerstones of relations between people and the environment, the use of energy from Renewable Energy Sources (RES) has become a fundamental element of this new vision. After years of vain attempts to hammer out an agreement to significantly reduce CO_2 emissions produced by the burning of fossil fuels, a binding global accord was finally reached (Paris December 2015 - New York April 2016). As we know, however, some of the most commonly-used RES, such as solar or wind, present the problem of discontinuity in energy production due to the variability of weather and climatic conditions. For this reason, the authors thought it appropriate to study a new methodology capable of marrying industrial users’ instantaneous need for energy with the production capacity of Renewable Energy Sources, supplemented, when necessary, by energy created through self-production and possibly acquired from third-party suppliers. All of this in order to minimize CO_2 emissions and company energy costs. Given the massive presence of stochastic and sometimes aleatory elements, for the proposed energy management model we have used both Monte Carlo simulation and on-line real-time Discrete Event Simulation (DES), as well as appropriate predictive algorithms. A test conducted on a tannery located in southern Italy, equipped with a 700 KWp photovoltaic installation, showed extremely interesting results, both economically and

  5. Laboratory-Scale Simulation and Real-Time Tracking of a Microbial Contamination Event and Subsequent Shock-Chlorination in Drinking Water

    Directory of Open Access Journals (Sweden)

    Michael D. Besmer

    2017-10-01

    Full Text Available Rapid contamination of drinking water in distribution and storage systems can occur due to pressure drop, backflow, cross-connections, accidents, and bio-terrorism. Small volumes of a concentrated contaminant (e.g., wastewater can contaminate large volumes of water in a very short time with potentially severe negative health impacts. The technical limitations of conventional, cultivation-based microbial detection methods neither allow for timely detection of such contaminations, nor for the real-time monitoring of subsequent emergency remediation measures (e.g., shock-chlorination. Here we applied a newly developed continuous, ultra high-frequency flow cytometry approach to track a rapid pollution event and subsequent disinfection of drinking water in an 80-min laboratory scale simulation. We quantified total (TCC and intact (ICC cell concentrations as well as flow cytometric fingerprints in parallel in real-time with two different staining methods. The ingress of wastewater was detectable almost immediately (i.e., after 0.6% volume change, significantly changing TCC, ICC, and the flow cytometric fingerprint. Shock chlorination was rapid and detected in real time, causing membrane damage in the vast majority of bacteria (i.e., drop of ICC from more than 380 cells μl-1 to less than 30 cells μl-1 within 4 min. Both of these effects as well as the final wash-in of fresh tap water followed calculated predictions well. Detailed and highly quantitative tracking of microbial dynamics at very short time scales and for different characteristics (e.g., concentration, membrane integrity is feasible. This opens up multiple possibilities for targeted investigation of a myriad of bacterial short-term dynamics (e.g., disinfection, growth, detachment, operational changes both in laboratory-scale research and full-scale system investigations in practice.

  6. Real time ammonia detection in exhaled human breath using a distributed feedback quantum cascade laser based sensor

    Science.gov (United States)

    Lewicki, Rafał; Kosterev, Anatoliy A.; Thomazy, David M.; Risby, Terence H.; Solga, Steven; Schwartz, Timothy B.; Tittel, Frank K.

    2011-01-01

    A continuous wave, thermoelectrically cooled, distributed feedback quantum cascade laser (DFB-QCL) based sensor platform for the quantitative detection of ammonia (NH3) concentrations present in exhaled human breath is reported. The NH3 concentration measurements are performed with a 2f wavelength modulation quartz enhanced photoacoustic spectroscopy (QEPAS) technique, which is very well suited for real time breath analysis, due to the fast gas exchange inside a compact QEPAS gas cell. An air-cooled DFB-QCL was designed to target the interference-free NH3 absorption line located at 967.35 cm-1 (λ~10.34 μm). The laser is operated at 17.5 °C, emitting ~ 24 mW of optical power at the selected wavelength. A 1σ minimum detectable concentration of ammonia for the line-locked NH3 sensor is ~ 6 ppb with 1 sec time resolution. The NH3 sensor, packaged in a 12"x14"x10" housing, is currently installed at a medical breath research center in Bethlehem, PA and tested as an instrument for non-invasive verification of liver and kidney disorders based on human breath samples.

  7. Fusion of hyperspectral remote sensing data for near real-time monitoring of microcystin distribution in Lake Erie

    Science.gov (United States)

    Vannah, Benjamin; Chang, Ni-Bin

    2013-09-01

    Urban growth and agricultural production have caused an influx of nutrients into Lake Erie, leading to eutrophic zones. These conditions result in the formation of algal blooms, some of which are toxic due to the presence of Microcystis (a cyanobacteria), which produces the hepatotoxin microcystin. Microcystis has a unique advantage over its competition as a result of the invasive zebra mussel population that filters algae out of the water column except for the toxic Microcystis. The toxin threatens human health and the ecosystem, and it is a concern for water treatment plants using the lake water as a tap water source. This presentation demonstrates the prototype of a near real-time early warning system using Integrated Data Fusion techniques with the aid of both hyperspectral remote sensing data to determine spatiotemporal microcystin concentrations. The temporal resolution of MODIS is fused with the higher spatial and spectral resolution of MERIS to create synthetic images on a daily basis. As a demonstration, the spatiotemporal distributions of microcystin within western Lake Erie are reconstructed using the band data from the fused products and applied machine-learning techniques. Analysis of the results through statistical indices confirmed that the this type of algorithm has better potential to accurately estimating microcystin concentrations in the lake, which is better than current two band models and other computational intelligence models.

  8. The SSABLE system - Automated archive, catalog, browse and distribution of satellite data in near-real time

    Science.gov (United States)

    Simpson, James J.; Harkins, Daniel N.

    1993-01-01

    Historically, locating and browsing satellite data has been a cumbersome and expensive process. This has impeded the efficient and effective use of satellite data in the geosciences. SSABLE is a new interactive tool for the archive, browse, order, and distribution of satellite date based upon X Window, high bandwidth networks, and digital image rendering techniques. SSABLE provides for automatically constructing relational database queries to archived image datasets based on time, data, geographical location, and other selection criteria. SSABLE also provides a visual representation of the selected archived data for viewing on the user's X terminal. SSABLE is a near real-time system; for example, data are added to SSABLE's database within 10 min after capture. SSABLE is network and machine independent; it will run identically on any machine which satisfies the following three requirements: 1) has a bitmapped display (monochrome or greater); 2) is running the X Window system; and 3) is on a network directly reachable by the SSABLE system. SSABLE has been evaluated at over 100 international sites. Network response time in the United States and Canada varies between 4 and 7 s for browse image updates; reported transmission times to Europe and Australia typically are 20-25 s.

  9. Towards a Cloud Computing Environment: Near Real-time Cloud Product Processing and Distribution for Next Generation Satellites

    Science.gov (United States)

    Nguyen, L.; Chee, T.; Minnis, P.; Palikonda, R.; Smith, W. L., Jr.; Spangenberg, D.

    2016-12-01

    The NASA LaRC Satellite ClOud and Radiative Property retrieval System (SatCORPS) processes and derives near real-time (NRT) global cloud products from operational geostationary satellite imager datasets. These products are being used in NRT to improve forecast model, aircraft icing warnings, and support aircraft field campaigns. Next generation satellites, such as the Japanese Himawari-8 and the upcoming NOAA GOES-R, present challenges for NRT data processing and product dissemination due to the increase in temporal and spatial resolution. The volume of data is expected to increase to approximately 10 folds. This increase in data volume will require additional IT resources to keep up with the processing demands to satisfy NRT requirements. In addition, these resources are not readily available due to cost and other technical limitations. To anticipate and meet these computing resource requirements, we have employed a hybrid cloud computing environment to augment the generation of SatCORPS products. This paper will describe the workflow to ingest, process, and distribute SatCORPS products and the technologies used. Lessons learn from working on both AWS Clouds and GovCloud will be discussed: benefits, similarities, and differences that could impact decision to use cloud computing and storage. A detail cost analysis will be presented. In addition, future cloud utilization, parallelization, and architecture layout will be discussed for GOES-R.

  10. Examining real-time time-dependent density functional theory nonequilibrium simulations for the calculation of electronic stopping power

    Science.gov (United States)

    Yost, Dillon C.; Yao, Yi; Kanai, Yosuke

    2017-09-01

    In ion irradiation processes, electronic stopping power describes the energy transfer rate from the irradiating ion to the target material's electrons. Due to the scarcity and significant uncertainties in experimental electronic stopping power data for materials beyond simple solids, there has been growing interest in the use of first-principles theory for calculating electronic stopping power. In recent years, advances in high-performance computing have opened the door to fully first-principles nonequilibrium simulations based on real-time time-dependent density functional theory (RT-TDDFT). While it has been demonstrated that the RT-TDDFT approach is capable of predicting electronic stopping power for a wide range of condensed matter systems, there has yet to be an exhaustive examination of the physical and numerical approximations involved and their effects on the calculated stopping power. We discuss the results of such a study for crystalline silicon with protons as irradiating ions. We examine the influences of key approximations in RT-TDDFT nonequilibrium simulations on the calculated electronic stopping power, including approximations related to basis sets, finite size effects, exchange-correlation approximation, pseudopotentials, and more. Finally, we propose a simple and efficient correction scheme to account for the contribution from core-electron excitations to the stopping power, as it was found to be significant for large proton velocities.

  11. Network dynamics with BrainX(3): a large-scale simulation of the human brain network with real-time interaction.

    Science.gov (United States)

    Arsiwalla, Xerxes D; Zucca, Riccardo; Betella, Alberto; Martinez, Enrique; Dalmazzo, David; Omedas, Pedro; Deco, Gustavo; Verschure, Paul F M J

    2015-01-01

    BrainX(3) is a large-scale simulation of human brain activity with real-time interaction, rendered in 3D in a virtual reality environment, which combines computational power with human intuition for the exploration and analysis of complex dynamical networks. We ground this simulation on structural connectivity obtained from diffusion spectrum imaging data and model it on neuronal population dynamics. Users can interact with BrainX(3) in real-time by perturbing brain regions with transient stimulations to observe reverberating network activity, simulate lesion dynamics or implement network analysis functions from a library of graph theoretic measures. BrainX(3) can thus be used as a novel immersive platform for exploration and analysis of dynamical activity patterns in brain networks, both at rest or in a task-related state, for discovery of signaling pathways associated to brain function and/or dysfunction and as a tool for virtual neurosurgery. Our results demonstrate these functionalities and shed insight on the dynamics of the resting-state attractor. Specifically, we found that a noisy network seems to favor a low firing attractor state. We also found that the dynamics of a noisy network is less resilient to lesions. Our simulations on TMS perturbations show that even though TMS inhibits most of the network, it also sparsely excites a few regions. This is presumably due to anti-correlations in the dynamics and suggests that even a lesioned network can show sparsely distributed increased activity compared to healthy resting-state, over specific brain areas.

  12. Network dynamics with BrainX3: a large-scale simulation of the human brain network with real-time interaction

    Science.gov (United States)

    Arsiwalla, Xerxes D.; Zucca, Riccardo; Betella, Alberto; Martinez, Enrique; Dalmazzo, David; Omedas, Pedro; Deco, Gustavo; Verschure, Paul F. M. J.

    2015-01-01

    BrainX3 is a large-scale simulation of human brain activity with real-time interaction, rendered in 3D in a virtual reality environment, which combines computational power with human intuition for the exploration and analysis of complex dynamical networks. We ground this simulation on structural connectivity obtained from diffusion spectrum imaging data and model it on neuronal population dynamics. Users can interact with BrainX3 in real-time by perturbing brain regions with transient stimulations to observe reverberating network activity, simulate lesion dynamics or implement network analysis functions from a library of graph theoretic measures. BrainX3 can thus be used as a novel immersive platform for exploration and analysis of dynamical activity patterns in brain networks, both at rest or in a task-related state, for discovery of signaling pathways associated to brain function and/or dysfunction and as a tool for virtual neurosurgery. Our results demonstrate these functionalities and shed insight on the dynamics of the resting-state attractor. Specifically, we found that a noisy network seems to favor a low firing attractor state. We also found that the dynamics of a noisy network is less resilient to lesions. Our simulations on TMS perturbations show that even though TMS inhibits most of the network, it also sparsely excites a few regions. This is presumably due to anti-correlations in the dynamics and suggests that even a lesioned network can show sparsely distributed increased activity compared to healthy resting-state, over specific brain areas. PMID:25759649

  13. Real Time Text Analysis

    Science.gov (United States)

    Senthilkumar, K.; Ruchika Mehra Vijayan, E.

    2017-11-01

    This paper aims to illustrate real time analysis of large scale data. For practical implementation we are performing sentiment analysis on live Twitter feeds for each individual tweet. To analyze sentiments we will train our data model on sentiWordNet, a polarity assigned wordNet sample by Princeton University. Our main objective will be to efficiency analyze large scale data on the fly using distributed computation. Apache Spark and Apache Hadoop eco system is used as distributed computation platform with Java as development language

  14. Seismic performance evaluation of an MR elastomer-based smart base isolation system using real-time hybrid simulation

    International Nuclear Information System (INIS)

    Eem, S H; Jung, H J; Koo, J H

    2013-01-01

    Recently, magneto-rheological (MR) elastomer-based base isolation systems have been actively studied as alternative smart base isolation systems because MR elastomers are capable of adjusting their modulus or stiffness depending on the magnitude of the applied magnetic field. By taking advantage of the MR elastomers’ stiffness-tuning ability, MR elastomer-based smart base isolation systems strive to alleviate limitations of existing smart base isolation systems as well as passive-type base isolators. Until now, research on MR elastomer-based base isolation systems primarily focused on characterization, design, and numerical evaluations of MR elastomer-based isolators, as well as experimental tests with simple structure models. However, their applicability to large civil structures has not been properly studied yet because it is quite challenging to numerically emulate the complex behavior of MR elastomer-based isolators and to conduct experiments with large-size structures. To address these difficulties, this study employs the real-time hybrid simulation technique, which combines physical testing and computational modeling. The primary goal of the current hybrid simulation study is to evaluate seismic performances of an MR elastomer-based smart base isolation system, particularly its adaptability to distinctly different seismic excitations. In the hybrid simulation, a single-story building structure (non-physical, computational model) is coupled with a physical testing setup for a smart base isolation system with associated components (such as laminated MR elastomers and electromagnets) installed on a shaking table. A series of hybrid simulations is carried out under two seismic excitations having different dominant frequencies. The results show that the proposed smart base isolation system outperforms the passive base isolation system in reducing the responses of the structure for the excitations considered in this study. (paper)

  15. Digital Controller Development Methodology Based on Real-Time Simulations with LabVIEW FPGA Hardware-Software Toolset

    Directory of Open Access Journals (Sweden)

    Tommaso Caldognetto

    2013-12-01

    Full Text Available In this paper, we exemplify the use of NI Lab-VIEW FPGA as a rapid prototyping environment for digital controllers. In our power electronics laboratory, it has been successfully employed in the development, debugging, and test of different power converter controllers for microgrid applications.The paper shows how this high level programming language,together with its target hardware platforms, including CompactRIO and Single Board RIO systems, allows researchers and students to develop even complex applications in reasonable times. The availability of efficient drivers for the considered hardware platforms frees the users from the burden of low level programming. At the same time, the high level programming approach facilitates software re-utilization, allowing the laboratory know-how to steadily grow along time. Furthermore, it allows hardware-in-the-loop real-time simulation, that proved to be effective, and safe, in debugging even complex hardware and software co-designed controllers. To illustrate the effectiveness of these hardware-software toolsets and of the methodology based upon them, two case studies are

  16. SNAVA-A real-time multi-FPGA multi-model spiking neural network simulation architecture.

    Science.gov (United States)

    Sripad, Athul; Sanchez, Giovanny; Zapata, Mireya; Pirrone, Vito; Dorta, Taho; Cambria, Salvatore; Marti, Albert; Krishnamourthy, Karthikeyan; Madrenas, Jordi

    2018-01-01

    Spiking Neural Networks (SNN) for Versatile Applications (SNAVA) simulation platform is a scalable and programmable parallel architecture that supports real-time, large-scale, multi-model SNN computation. This parallel architecture is implemented in modern Field-Programmable Gate Arrays (FPGAs) devices to provide high performance execution and flexibility to support large-scale SNN models. Flexibility is defined in terms of programmability, which allows easy synapse and neuron implementation. This has been achieved by using a special-purpose Processing Elements (PEs) for computing SNNs, and analyzing and customizing the instruction set according to the processing needs to achieve maximum performance with minimum resources. The parallel architecture is interfaced with customized Graphical User Interfaces (GUIs) to configure the SNN's connectivity, to compile the neuron-synapse model and to monitor SNN's activity. Our contribution intends to provide a tool that allows to prototype SNNs faster than on CPU/GPU architectures but significantly cheaper than fabricating a customized neuromorphic chip. This could be potentially valuable to the computational neuroscience and neuromorphic engineering communities. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Model-driven requirements engineering (MDRE) for real-time ultra-wide instantaneous bandwidth signal simulation

    Science.gov (United States)

    Chang, Daniel Y.; Rowe, Neil C.

    2013-05-01

    While conducting a cutting-edge research in a specific domain, we realize that (1) requirements clarity and correctness are crucial to our success [1], (2) hardware is hard to change, most work is in software requirements development, coding and testing [2], (3) requirements are constantly changing, so that configurability, reusability, scalability, adaptability, modularity and testability are important non-functional attributes [3], (4) cross-domain knowledge is necessary for complex systems [4], and (5) if our research is successful, the results could be applied to other domains with similar problems. In this paper, we propose to use model-driven requirements engineering (MDRE) to model and guide our requirements/development, since models are easy to understand, execute, and modify. The domain for our research is Electronic Warfare (EW) real-time ultra-wide instantaneous bandwidth (IBW1) signal simulation. The proposed four MDRE models are (1) Switch-and-Filter architecture, (2) multiple parallel data bit streams alignment, (3) post-ADC and pre-DAC bits re-mapping, and (4) Discrete Fourier Transform (DFT) filter bank. This research is unique since the instantaneous bandwidth we are dealing with is in gigahertz range instead of conventional megahertz.

  18. Estimating medication stopping fraction and real-time prevalence of drug use in pharmaco-epidemiologic databases. An application of the reverse waiting time distribution

    DEFF Research Database (Denmark)

    Støvring, Henrik; Pottegård, Anton; Hallas, Jesper

    2017-01-01

    Purpose: To introduce the reverse waiting time distribution (WTD) and show how it can be used to estimate stopping fractions and real-time prevalence of treatment in pharmacoepidemiological studies. Methods: The reverse WTD is the distribution of time from the last dispensed prescription of each......-hoc decision rules for automated implementations, and it yields estimates of real-time prevalence....... patient within a time window to the end of it. It is a mirrored version of the ordinary WTD, which considers the first dispensed prescription of patients within a time window. Based on renewal process theory, the reverse WTD can be analyzed as an ordinary WTD with maximum likelihood estimation. Based...

  19. Real-time simulation of electric motors. Applying software and control theory; Echtzeit-Simulation von E-Maschinen. Regelungstechnik im Hybridantrieb

    Energy Technology Data Exchange (ETDEWEB)

    Werner, Joerg; Tauber, Hermann [Silver-Atena, Muenchen (Germany)

    2010-02-15

    Developments in the electric drive-train have the highest priority, but all the same proven development methods are not consequently applied. For example the simulation of the hybrid drive-train excludes the e-motor and its system environment such as the corresponding controllers. ''Too complex and too much effort'', is the justification. Silver-Atena produces a proof of the contrary and achieves with a real-time simulation of an electric machine using the Hardware-in-the-loop technique more precise system verifications. Despite the undoubtedly high complexity Software- and Control-Theory engineers can thus work more efficiently. (orig.)

  20. Scalable Real-Time Negotiation Toolkit

    National Research Council Canada - National Science Library

    Lesser, Victor

    2004-01-01

    ... to implement an adaptive distributed sensor network. These activities involved the development of a distributed soft, real-time heuristic resource allocation protocol, the development of a domain-independent soft, real time agent architecture...