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Sample records for point-to-point distributed systems

  1. Digital microwave communication engineering point-to-point microwave systems

    CERN Document Server

    Kizer, George

    2013-01-01

    The first book to cover all engineering aspects of microwave communication path design for the digital age Fixed point-to-point microwave systems provide moderate-capacity digital transmission between well-defined locations. Most popular in situations where fiber optics or satellite communication is impractical, it is commonly used for cellular or PCS site interconnectivity where digital connectivity is needed but not economically available from other sources, and in private networks where reliability is most important. Until now, no book has adequately treated all en

  2. Transmission system for distribution of video over long-haul optical point-to-point links using a microwave photonic filter in the frequency range of 0.01-10 GHz

    Science.gov (United States)

    Zaldívar Huerta, Ignacio E.; Pérez Montaña, Diego F.; Nava, Pablo Hernández; Juárez, Alejandro García; Asomoza, Jorge Rodríguez; Leal Cruz, Ana L.

    2013-12-01

    We experimentally demonstrate the use of an electro-optical transmission system for distribution of video over long-haul optical point-to-point links using a microwave photonic filter in the frequency range of 0.01-10 GHz. The frequency response of the microwave photonic filter consists of four band-pass windows centered at frequencies that can be tailored to the function of the spectral free range of the optical source, the chromatic dispersion parameter of the optical fiber used, as well as the length of the optical link. In particular, filtering effect is obtained by the interaction of an externally modulated multimode laser diode emitting at 1.5 μm associated to the length of a dispersive optical fiber. Filtered microwave signals are used as electrical carriers to transmit TV-signal over long-haul optical links point-to-point. Transmission of TV-signal coded on the microwave band-pass windows located at 4.62, 6.86, 4.0 and 6.0 GHz are achieved over optical links of 25.25 km and 28.25 km, respectively. Practical applications for this approach lie in the field of the FTTH access network for distribution of services as video, voice, and data.

  3. Network Competition - the Coexistence of Hub-and-Spoke and Point-to-Point Systems

    NARCIS (Netherlands)

    Alderighi, M.; Cento, A.; Nijkamp, P.; Rietveld, P.

    2005-01-01

    The paper identifies conditions under which asymmetric equilibria may exist when carriers compete in designing their network configurations in a game-theoretical framework. Two carriers are assumed here, which are allowed to play three different strategies: Point-to-point (PP), hub-and-spoke (HS) or

  4. Point-to-Point! Validation of the Small Aircraft Transportation System Higher Volume Operations Concept

    Science.gov (United States)

    Williams, Daniel M.

    2006-01-01

    Described is the research process that NASA researchers used to validate the Small Aircraft Transportation System (SATS) Higher Volume Operations (HVO) concept. The four phase building-block validation and verification process included multiple elements ranging from formal analysis of HVO procedures to flight test, to full-system architecture prototype that was successfully shown to the public at the June 2005 SATS Technical Demonstration in Danville, VA. Presented are significant results of each of the four research phases that extend early results presented at ICAS 2004. HVO study results have been incorporated into the development of the Next Generation Air Transportation System (NGATS) vision and offer a validated concept to provide a significant portion of the 3X capacity improvement sought after in the United States National Airspace System (NAS).

  5. 60 GHz Milimeter-Wave Antennas for Point-to-Point 5G Communication System

    Directory of Open Access Journals (Sweden)

    Aishah A.S.

    2017-01-01

    Full Text Available In this paper microstrip patch antenna for millimeter-wave is proposed. Evolution of shape microstrip antenna are designed which is from rectangular antenna to triangle antenna and changed to triangle with slot. The proposed antenna configuration achieved for covering 5G wireless system. The lowest return loss of the antenna is -29.23dB which is triangle with slot and the maximum gain obtained is 8 db at the 61.93 GHz for the triangle antenna. This antenna are suitable for the 5G wireless application for short range and high rate communication system.

  6. On the Required Number of Antennas in a Point-to-Point Large-but-Finite MIMO System

    KAUST Repository

    Makki, Behrooz; Svensson, Tommy; Eriksson, Thomas; Alouini, Mohamed-Slim

    2015-01-01

    In this paper, we investigate the performance of the point-to-point multiple-input-multiple-output (MIMO) systems in the presence of a large but finite numbers of antennas at the transmitters and/or receivers. Considering the cases with and without hybrid automatic repeat request (HARQ) feedback, we determine the minimum numbers of the transmit/receive antennas which are required to satisfy different outage probability constraints. We study the effect of the spatial correlation between the antennas on the system performance. Also, the required number of antennas are obtained for different fading conditions. Our results show that different outage requirements can be satisfied with relatively few transmit/receive antennas. © 2015 IEEE.

  7. On the Required Number of Antennas in a Point-to-Point Large-but-Finite MIMO System

    KAUST Repository

    Makki, Behrooz

    2015-11-12

    In this paper, we investigate the performance of the point-to-point multiple-input-multiple-output (MIMO) systems in the presence of a large but finite numbers of antennas at the transmitters and/or receivers. Considering the cases with and without hybrid automatic repeat request (HARQ) feedback, we determine the minimum numbers of the transmit/receive antennas which are required to satisfy different outage probability constraints. We study the effect of the spatial correlation between the antennas on the system performance. Also, the required number of antennas are obtained for different fading conditions. Our results show that different outage requirements can be satisfied with relatively few transmit/receive antennas. © 2015 IEEE.

  8. On the Required Number of Antennas in a Point-to-Point Large-but-Finite MIMO System: Outage-Limited Scenario

    KAUST Repository

    Makki, Behrooz

    2016-03-22

    This paper investigates the performance of the point-To-point multiple-input-multiple-output (MIMO) systems in the presence of a large but finite numbers of antennas at the transmitters and/or receivers. Considering the cases with and without hybrid automatic repeat request (HARQ) feedback, we determine the minimum numbers of the transmit/receive antennas, which are required to satisfy different outage probability constraints. Our results are obtained for different fading conditions and the effect of the power amplifiers efficiency/feedback error probability on the performance of the MIMO-HARQ systems is analyzed. Then, we use some recent results on the achievable rates of finite block-length codes, to analyze the effect of the codewords lengths on the system performance. Moreover, we derive closed-form expressions for the asymptotic performance of the MIMO-HARQ systems when the number of antennas increases. Our analytical and numerical results show that different outage requirements can be satisfied with relatively few transmit/receive antennas. © 1972-2012 IEEE.

  9. Determine point-to-point networking interactions using regular expressions

    Directory of Open Access Journals (Sweden)

    Konstantin S. Deev

    2015-06-01

    Full Text Available As Internet growth and becoming more popular, the number of concurrent data flows start to increasing, which makes sense in bandwidth requested. Providers and corporate customers need ability to identify point-to-point interactions. The best is to use special software and hardware implementations that distribute the load in the internals of the complex, using the principles and approaches, in particular, described in this paper. This paper represent the principles of building system, which searches for a regular expression match using computing on graphics adapter in server station. A significant computing power and capability to parallel execution on modern graphic processor allows inspection of large amounts of data through sets of rules. Using the specified characteristics can lead to increased computing power in 30…40 times compared to the same setups on the central processing unit. The potential increase in bandwidth capacity could be used in systems that provide packet analysis, firewalls and network anomaly detectors.

  10. Error Mitigation of Point-to-Point Communication for Fault-Tolerant Computing

    Science.gov (United States)

    Akamine, Robert L.; Hodson, Robert F.; LaMeres, Brock J.; Ray, Robert E.

    2011-01-01

    Fault tolerant systems require the ability to detect and recover from physical damage caused by the hardware s environment, faulty connectors, and system degradation over time. This ability applies to military, space, and industrial computing applications. The integrity of Point-to-Point (P2P) communication, between two microcontrollers for example, is an essential part of fault tolerant computing systems. In this paper, different methods of fault detection and recovery are presented and analyzed.

  11. Point to point multispectral light projection applied to cultural heritage

    Science.gov (United States)

    Vázquez, D.; Alvarez, A.; Canabal, H.; Garcia, A.; Mayorga, S.; Muro, C.; Galan, T.

    2017-09-01

    Use of new of light sources based on LED technology should allow the develop of systems that combine conservation and exhibition requirements and allow to make these art goods available to the next generations according to sustainability principles. The goal of this work is to develop light systems and sources with an optimized spectral distribution for each specific point of the art piece. This optimization process implies to maximize the color fidelity reproduction and the same time to minimize the photochemical damage. Perceived color under these sources will be similar (metameric) to technical requirements given by the restoration team uncharged of the conservation and exhibition of the goods of art. Depending of the fragility of the exposed art objects (i.e. spectral responsivity of the material) the irradiance must be kept under a critical level. Therefore, it is necessary to develop a mathematical model that simulates with enough accuracy both the visual effect of the illumination and the photochemical impact of the radiation. Spectral reflectance of a reference painting The mathematical model is based on a merit function that optimized the individual intensity of the LED-light sources taking into account the damage function of the material and color space coordinates. Moreover the algorithm used weights for damage and color fidelity in order to adapt the model to a specific museal application. In this work we show a sample of this technology applied to a picture of Sorolla (1863-1923) an important Spanish painter title "woman walking at the beach".

  12. A Survivable Wavelength Division Multiplexing Passive Optical Network with Both Point-to-Point Service and Broadcast Service Delivery

    Science.gov (United States)

    Ma, Xuejiao; Gan, Chaoqin; Deng, Shiqi; Huang, Yan

    2011-11-01

    A survivable wavelength division multiplexing passive optical network enabling both point-to-point service and broadcast service is presented and demonstrated. This architecture provides an automatic traffic recovery against feeder and distribution fiber link failure, respectively. In addition, it also simplifies the protection design for multiple services transmission in wavelength division multiplexing passive optical networks.

  13. Point-to-point radio link variation at E-band and its effect on antenna design

    NARCIS (Netherlands)

    Al-Rawi, A.; Dubok, A.; Herben, M.H.A.J.; Smolders, A.B.

    2015-01-01

    Radio propagation will strongly influence the design of the antenna and front-end components of E-band point-to-point communication systems. Based on the ITU rain model, the rain attenuation is estimated in a statistical sense and it is concluded that for backhaul links of 1–10 km, antennas with a

  14. Point-to-point people with purpose—Exploring the possibility of a commercial traveler market for point-to-point suborbital space transportation

    Science.gov (United States)

    Webber, Derek

    2013-12-01

    An argument was made at the First Arcachon Conference on Private Human Access to Space in 2008 [1] that some systematic market research should be conducted into potential market segments for point-to-point suborbital space transportation (PtP), in order to understand whether a commercial market exists which might augment possible government use for such a vehicle. The cargo market potential was subsequently addressed via desk research, and the results, which resulted in a pessimistic business case outlook, were presented in [2]. The same desk research approach is now used in this paper to address the potential business and wealthy individual passenger traveler market segment ("point-to-point people with purpose"). The results, with the assumed ticket pricing, are not encouraging.

  15. May 2002 Lidar Point Data of Southern California Coastline: Dana Point to Point La Jolla

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains lidar point data from a strip of Southern California coastline (including water, beach, cliffs, and top of cliffs) from Dana Point to Point La...

  16. September 2002 Lidar Point Data of Southern California Coastline: Dana Point to Point La Jolla

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains lidar point data from a strip of Southern California coastline (including water, beach, cliffs, and top of cliffs) from Dana Point to Point La...

  17. Point-to-point microwave power transmission experiment; Maikuroha ni yoru denryoku yuso no kiso kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Shimokura, N.; Kirihara, T. [Kansai Electric Power Co. Inc., Osaka (Japan)

    1997-09-30

    In order to demonstrate the power transmission using microwave and arrange advantages and problems in the wireless power transmission, field tests of point-to-point power transmission were conducted. Microwave frequency of 2.45 GHz was used, which is assigned as the industrial, scientific and medical frequency. The transmission system is composed of generator, director tube, primary radiator, and transmission antenna. The maximum 5 kW of microwave power can be transmitted by combining a 3 m-diameter parabolic antenna and a magnetron. The receiving system is composed of devices called as RECTENNA (rectifying antenna). A large capacity and high efficiency RECTENNA was developed, by which the maximum 2.5 W of input power per single device can be provided. As a result of the experiments, efficiency at the transmission side was over 70%, and RF-DC efficiency at the receiving side was about 51%. At the open-air test site, however, the total efficiency of only 14.8% could be obtained. 8 refs., 12 figs.

  18. The timing of control signals underlying fast point-to-point arm movements.

    Science.gov (United States)

    Ghafouri, M; Feldman, A G

    2001-04-01

    It is known that proprioceptive feedback induces muscle activation when the facilitation of appropriate motoneurons exceeds their threshold. In the suprathreshold range, the muscle-reflex system produces torques depending on the position and velocity of the joint segment(s) that the muscle spans. The static component of the torque-position relationship is referred to as the invariant characteristic (IC). According to the equilibrium-point (EP) hypothesis, control systems produce movements by changing the activation thresholds and thus shifting the IC of the appropriate muscles in joint space. This control process upsets the balance between muscle and external torques at the initial limb configuration and, to regain the balance, the limb is forced to establish a new configuration or, if the movement is prevented, a new level of static torques. Taken together, the joint angles and the muscle torques generated at an equilibrium configuration define a single variable called the EP. Thus by shifting the IC, control systems reset the EP. Muscle activation and movement emerge following the EP resetting because of the natural physical tendency of the system to reach equilibrium. Empirical and simulation studies support the notion that the control IC shifts and the resulting EP shifts underlying fast point-to-point arm movements are gradual rather than step-like. However, controversies exist about the duration of these shifts. Some studies suggest that the IC shifts cease with the movement offset. Other studies propose that the IC shifts end early in comparison to the movement duration (approximately, at peak velocity). The purpose of this study was to evaluate the duration of the IC shifts underlying fast point-to-point arm movements. Subjects made fast (hand peak velocity about 1.3 m/s) planar arm movements toward different targets while grasping a handle. Hand forces applied to the handle and shoulder/elbow torques were, respectively, measured from a force sensor placed

  19. Spectrography analysis of stainless steel by the point to point technique

    International Nuclear Information System (INIS)

    Bona, A.

    1986-01-01

    A method for the determination of the elements Ni, Cr, Mn, Si, Mo, Nb, Cu, Co and V in stainless steel by emission spectrographic analysis using high voltage spark sources is presented. The 'point-to-point' technique is employed. The experimental parameters were optimized taking account a compromise between the detection sensitivity and the precision of the measurement. The parameters investigated were the high voltage capacitance, the inductance, the analytical and auxiliary gaps, the period of pre burn spark and the time of exposure. The edge shape of the counter electrodes and the type of polishing and diameter variation of the stailess steel eletrodes were evaluated in preliminary assays. In addition the degradation of the chemical power of the developer was also investigated. Counter electrodes of graphite, copper, aluminium and iron were employed and the counter electrode itself was used as an internal standard. In the case of graphite counter electrodes the iron lines were employed as internal standard. The relative errors were the criteria for evaluation of these experiments. The National Bureau of Standards - Certified reference stainless steel standards and the Eletrometal Acos Finos S.A. samples (certified by the supplier) were employed for drawing in the calibration systems and analytical curves. The best results were obtained using the convencional graphite counter electrodes. The inaccuracy and the imprecision of the proposed method varied from 2% to 15% and from 1% to 9% respectively. This present technique was compared to others instrumental techniques such as inductively coupled plasma, X-ray fluorescence and neutron activation analysis. The advantages and disadvantages for each case were discussed. (author) [pt

  20. Octopuses use a human-like strategy to control precise point-to-point arm movements.

    Science.gov (United States)

    Sumbre, Germán; Fiorito, Graziano; Flash, Tamar; Hochner, Binyamin

    2006-04-18

    One of the key problems in motor control is mastering or reducing the number of degrees of freedom (DOFs) through coordination. This problem is especially prominent with hyper-redundant limbs such as the extremely flexible arm of the octopus. Several strategies for simplifying these control problems have been suggested for human point-to-point arm movements. Despite the evolutionary gap and morphological differences, humans and octopuses evolved similar strategies when fetching food to the mouth. To achieve this precise point-to-point-task, octopus arms generate a quasi-articulated structure based on three dynamic joints. A rotational movement around these joints brings the object to the mouth . Here, we describe a peripheral neural mechanism-two waves of muscle activation propagate toward each other, and their collision point sets the medial-joint location. This is a remarkably simple mechanism for adjusting the length of the segments according to where the object is grasped. Furthermore, similar to certain human arm movements, kinematic invariants were observed at the joint level rather than at the end-effector level, suggesting intrinsic control coordination. The evolutionary convergence to similar geometrical and kinematic features suggests that a kinematically constrained articulated limb controlled at the level of joint space is the optimal solution for precise point-to-point movements.

  1. On Motion Planning for Point-to-Point Maneuvers for a Class of Sailing Vehicles

    DEFF Research Database (Denmark)

    Xiao, Lin; Jouffroy, Jerome

    2011-01-01

    Despite their interesting dynamic and controllability properties, sailing vehicles have not been much studied in the control community. In this paper, we investigate motion planning of such vehicles. Starting from a simple dynamic model of sailing vessels in one dimension, this paper first...... considers their associated controllability issues, with the so-called no-sailing zone as a starting point, and it links them with a motion planning strategy using two-point boundary value problems as the main mathematical tool. This perspective is then expanded to do point-to-point maneuvers of sailing...

  2. Optimal Point-to-Point Trajectory Tracking of Redundant Manipulators using Generalized Pattern Search

    Directory of Open Access Journals (Sweden)

    Thi Rein Myo

    2008-11-01

    Full Text Available Optimal point-to-point trajectory planning for planar redundant manipulator is considered in this study. The main objective is to minimize the sum of the position error of the end-effector at each intermediate point along the trajectory so that the end-effector can track the prescribed trajectory accurately. An algorithm combining Genetic Algorithm and Pattern Search as a Generalized Pattern Search GPS is introduced to design the optimal trajectory. To verify the proposed algorithm, simulations for a 3-D-O-F planar manipulator with different end-effector trajectories have been carried out. A comparison between the Genetic Algorithm and the Generalized Pattern Search shows that The GPS gives excellent tracking performance.

  3. TeleHealth networks: Instant messaging and point-to-point communication over the internet

    Energy Technology Data Exchange (ETDEWEB)

    Sachpazidis, Ilias [Fraunhofer Institute for Computer Graphics, Fraunhoferstr. 5, D-64283, Darmstadt (Germany)]. E-mail: Ilias.Sachpazidis@igd.fraunhofer.de; Ohl, Roland [MedCom Gesellschaft fuer medizinische Bildverarbeitung mbH, Runderturmstr. 12, D-64283, Darmstadt (Germany); Kontaxakis, George [Universidad Politecnica de Madrid, ETSI Telecomunicacion, Madrid 28040 (Spain); Sakas, Georgios [Fraunhofer Institute for Computer Graphics, Fraunhoferstr. 5, D-64283, Darmstadt (Germany)

    2006-12-20

    This paper explores the advantages and disadvantages of a medical network based on point-to-point communication and a medical network based on Jabber instant messaging protocol. Instant messaging might be, for many people, a convenient way of chatting over the Internet. We will attempt to illustrate how an instant messaging protocol could serve in the best way medical services and provide great flexibility to the involved parts. Additionally, the directory services and presence status offered by the Jabber protocol make it very attractive to medical applications that need to have real time and store and forward communication. Furthermore, doctors connected to Internet via high-speed networks could benefit by saving time due to the data transmission acceleration over Jabber.

  4. TeleHealth networks: Instant messaging and point-to-point communication over the internet

    Science.gov (United States)

    Sachpazidis, Ilias; Ohl, Roland; Kontaxakis, George; Sakas, Georgios

    2006-12-01

    This paper explores the advantages and disadvantages of a medical network based on point-to-point communication and a medical network based on Jabber instant messaging protocol. Instant messaging might be, for many people, a convenient way of chatting over the Internet. We will attempt to illustrate how an instant messaging protocol could serve in the best way medical services and provide great flexibility to the involved parts. Additionally, the directory services and presence status offered by the Jabber protocol make it very attractive to medical applications that need to have real time and store and forward communication. Furthermore, doctors connected to Internet via high-speed networks could benefit by saving time due to the data transmission acceleration over Jabber.

  5. TeleHealth networks: Instant messaging and point-to-point communication over the internet

    International Nuclear Information System (INIS)

    Sachpazidis, Ilias; Ohl, Roland; Kontaxakis, George; Sakas, Georgios

    2006-01-01

    This paper explores the advantages and disadvantages of a medical network based on point-to-point communication and a medical network based on Jabber instant messaging protocol. Instant messaging might be, for many people, a convenient way of chatting over the Internet. We will attempt to illustrate how an instant messaging protocol could serve in the best way medical services and provide great flexibility to the involved parts. Additionally, the directory services and presence status offered by the Jabber protocol make it very attractive to medical applications that need to have real time and store and forward communication. Furthermore, doctors connected to Internet via high-speed networks could benefit by saving time due to the data transmission acceleration over Jabber

  6. The study and analysis of point-to-point vibration isolation and its utility to seismic base isolator

    International Nuclear Information System (INIS)

    Mehboob, M.; Qureshi, A.S.

    2001-01-01

    This paper presents systematic approach to regarding the piece wise vibration isolation generally termed as point-to-point vibration isolation system, and its broad spectrum-utilities to an economic seismic base isolation. Transfer of curves for coulomb damped i.e. softening damper flexible mountings are presented and the utility has been proved equally good for both rigidly and elastically coupled damping. It is clearly shown that the very closest solutions are easily obtainable for both slipping and sticking nature of phases of the motion. This eliminates the conventional and conceptual approximations based on the linearization of the damping. This new concept will not endanger-super-structure if mounted on such isolation systems. (author)

  7. Limits in point to point resolution of MOS based pixels detector arrays

    Science.gov (United States)

    Fourches, N.; Desforge, D.; Kebbiri, M.; Kumar, V.; Serruys, Y.; Gutierrez, G.; Leprêtre, F.; Jomard, F.

    2018-01-01

    In high energy physics point-to-point resolution is a key prerequisite for particle detector pixel arrays. Current and future experiments require the development of inner-detectors able to resolve the tracks of particles down to the micron range. Present-day technologies, although not fully implemented in actual detectors, can reach a 5-μm limit, this limit being based on statistical measurements, with a pixel-pitch in the 10 μm range. This paper is devoted to the evaluation of the building blocks for use in pixel arrays enabling accurate tracking of charged particles. Basing us on simulations we will make here a quantitative evaluation of the physical and technological limits in pixel size. Attempts to design small pixels based on SOI technology will be briefly recalled here. A design based on CMOS compatible technologies that allow a reduction of the pixel size below the micrometer is introduced here. Its physical principle relies on a buried carrier-localizing collecting gate. The fabrication process needed by this pixel design can be based on existing process steps used in silicon microelectronics. The pixel characteristics will be discussed as well as the design of pixel arrays. The existing bottlenecks and how to overcome them will be discussed in the light of recent ion implantation and material characterization experiments.

  8. FDM and DMT performance comparison in high capacity point-to-point fibre links for intra/inter-datacentre connections

    Science.gov (United States)

    Gatto, A.; Parolari, P.; Boffi, P.

    2018-05-01

    Frequency division multiplexing (FDM) is attractive to achieve high capacities in multiple access networks characterized by direct modulation and direct detection. In this paper we take into account point-to-point intra- and inter-datacenter connections to understand the performance of FDM operation compared with the ones achievable with standard multiple carrier modulation approach based on discrete multitone (DMT). DMT and FDM allow to match the non-uniform and bandwidth-limited response of the system under test, associated with the employment of low-cost directly-modulated sources, such as VCSELs with high-frequency chirp, and with fibre-propagation in presence of chromatic dispersion. While for very short distances typical of intra-datacentre communications, the huge number of DMT subcarriers permits to increase the transported capacity with respect to the FDM employment, in case of few tens-km reaches typical of inter-datacentre connections, the capabilities of FDM are more evident, providing system performance similar to the case of DMT application.

  9. Novel transmission pricing scheme based on point-to-point tariff and transaction pair matching for pool market

    International Nuclear Information System (INIS)

    Chen, Qixin; Xia, Qing; Kang, Chongqing

    2010-01-01

    Transmission pricing scheme is a key component in the infrastructure of power market, and pool is an indispensable pattern of market organization; meanwhile, pay-as-bid (PAB) serves as a main option to determine market prices in pool. In this paper, a novel transmission pricing scheme is proposed for pool power market based on PAB. The new scheme is developed by utilizing point-to-point (PTP) tariff and introducing an approach of transaction pair matching (TPM). The model and procedure of the new scheme are presented in detail. Apart from the advantages of existing transmission pricing schemes, such as ensuing open, fair and non-discriminatory access, proper recovery for investment as well as transparency, the new scheme provides economic signals to promote the maximum use of the existing transmission network, encourages appropriate bidding behaviors in pool, and helps to reduce the possibility of the enforcement of market power and the appearing of price spikes; thus improves market operation efficiency and trading effects. In order to testify the effectiveness of the proposed scheme, a case based on IEEE 30-bus system is studied. (author)

  10. Novel transmission pricing scheme based on point-to-point tariff and transaction pair matching for pool market

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Qixin; Xia, Qing; Kang, Chongqing [State Key Lab. of Power System, Dept. of Electrical Engineering, Tsinghua University, Beijing 100084 (China)

    2010-04-15

    Transmission pricing scheme is a key component in the infrastructure of power market, and pool is an indispensable pattern of market organization; meanwhile, pay-as-bid (PAB) serves as a main option to determine market prices in pool. In this paper, a novel transmission pricing scheme is proposed for pool power market based on PAB. The new scheme is developed by utilizing point-to-point (PTP) tariff and introducing an approach of transaction pair matching (TPM). The model and procedure of the new scheme are presented in detail. Apart from the advantages of existing transmission pricing schemes, such as ensuing open, fair and non-discriminatory access, proper recovery for investment as well as transparency, the new scheme provides economic signals to promote the maximum use of the existing transmission network, encourages appropriate bidding behaviors in pool, and helps to reduce the possibility of the enforcement of market power and the appearing of price spikes; thus improves market operation efficiency and trading effects. In order to testify the effectiveness of the proposed scheme, a case based on IEEE 30-bus system is studied. (author)

  11. Application of the nudged elastic band method to the point-to-point radio wave ray tracing in IRI modeled ionosphere

    Science.gov (United States)

    Nosikov, I. A.; Klimenko, M. V.; Bessarab, P. F.; Zhbankov, G. A.

    2017-07-01

    Point-to-point ray tracing is an important problem in many fields of science. While direct variational methods where some trajectory is transformed to an optimal one are routinely used in calculations of pathways of seismic waves, chemical reactions, diffusion processes, etc., this approach is not widely known in ionospheric point-to-point ray tracing. We apply the Nudged Elastic Band (NEB) method to a radio wave propagation problem. In the NEB method, a chain of points which gives a discrete representation of the radio wave ray is adjusted iteratively to an optimal configuration satisfying the Fermat's principle, while the endpoints of the trajectory are kept fixed according to the boundary conditions. Transverse displacements define the radio ray trajectory, while springs between the points control their distribution along the ray. The method is applied to a study of point-to-point ionospheric ray tracing, where the propagation medium is obtained with the International Reference Ionosphere model taking into account traveling ionospheric disturbances. A 2-dimensional representation of the optical path functional is developed and used to gain insight into the fundamental difference between high and low rays. We conclude that high and low rays are minima and saddle points of the optical path functional, respectively.

  12. The FEROL40, a microTCA card interfacing custom point-to-point links and standard TCP/IP

    CERN Document Server

    Gigi, Dominique; Behrens, Ulf; Branson, James; Chaze, Olivier; Cittolin, Sergio; Contescu, Cristian; da Silva Gomes, Diego; Darlea, Georgiana-Lavinia; Deldicque, Christian; Demiragli, Zeynep; Dobson, Marc; Doualot, Nicolas; Erhan, Samim; Fulcher, Jonathan Richard; Gladki, Maciej; Glege, Frank; Gomez-Ceballos, Guillelmo; Hegeman, Jeroen; Holzner, Andre; Janulis, Mindaugas; Lettrich, Michael; Meijers, Frans; Meschi, Emilio; Mommsen, Remigius K; Morovic, Srecko; O'Dell, Vivian; Orn, Samuel Johan; Orsini, Luciano; Papakrivopoulos, Ioannis; Paus, Christoph; Petrova, Petia; Petrucci, Andrea; Pieri, Marco; Rabady, Dinyar; Racz, Attila; Reis, Thomas; Sakulin, Hannes; Schwick, Christoph; Simelevicius, Dainius; Vazquez Velez, Cristina; Vougioukas, Michail; Zejdl, Petr

    2017-01-01

    In order to accommodate new back-end electronics of upgraded CMS sub-detectors, a new FEROL40 card in the microTCA standard has been developed. The main function of the FEROL40 is to acquire event data over multiple point-to-point serial optical links, provide buffering, perform protocol conversion, and transmit multiple TCP/IP streams (4x10Gbps) to the Ethernet network of the aggregation layer of the CMS DAQ (data acquisition) event builder. This contribution discusses the design of the FEROL40 and experience from operation.

  13. Distributed systems

    CERN Document Server

    Van Steen, Maarten

    2017-01-01

    For this third edition of "Distributed Systems," the material has been thoroughly revised and extended, integrating principles and paradigms into nine chapters: 1. Introduction 2. Architectures 3. Processes 4. Communication 5. Naming 6. Coordination 7. Replication 8. Fault tolerance 9. Security A separation has been made between basic material and more specific subjects. The latter have been organized into boxed sections, which may be skipped on first reading. To assist in understanding the more algorithmic parts, example programs in Python have been included. The examples in the book leave out many details for readability, but the complete code is available through the book's Website, hosted at www.distributed-systems.net.

  14. Coding and decoding in a point-to-point communication using the polarization of the light beam.

    Science.gov (United States)

    Kavehvash, Z; Massoumian, F

    2008-05-10

    A new technique for coding and decoding of optical signals through the use of polarization is described. In this technique the concept of coding is translated to polarization. In other words, coding is done in such a way that each code represents a unique polarization. This is done by implementing a binary pattern on a spatial light modulator in such a way that the reflected light has the required polarization. Decoding is done by the detection of the received beam's polarization. By linking the concept of coding to polarization we can use each of these concepts in measuring the other one, attaining some gains. In this paper the construction of a simple point-to-point communication where coding and decoding is done through polarization will be discussed.

  15. Joint input shaping and feedforward for point-to-point motion : automated tuning for an industrial nanopositioning system

    NARCIS (Netherlands)

    Boeren, F.A.J.; Bruijnen, D.J.H.; Dijk, van N.J.M.; Oomen, T.A.E.

    2014-01-01

    Feedforward control can effectively compensate for the servo error induced by the reference signal if it is tuned appropriately. This paper aims to introduce a new joint input shaping and feedforward parametrization in iterative feedforward control. Such a parametrization has the potential to

  16. Neuromuscular control of the point to point and oscillatory movements of a sagittal arm with the actor-critic reinforcement learning method.

    Science.gov (United States)

    Golkhou, Vahid; Parnianpour, Mohamad; Lucas, Caro

    2005-04-01

    In this study, we have used a single link system with a pair of muscles that are excited with alpha and gamma signals to achieve both point to point and oscillatory movements with variable amplitude and frequency.The system is highly nonlinear in all its physical and physiological attributes. The major physiological characteristics of this system are simultaneous activation of a pair of nonlinear muscle-like-actuators for control purposes, existence of nonlinear spindle-like sensors and Golgi tendon organ-like sensor, actions of gravity and external loading. Transmission delays are included in the afferent and efferent neural paths to account for a more accurate representation of the reflex loops.A reinforcement learning method with an actor-critic (AC) architecture instead of middle and low level of central nervous system (CNS), is used to track a desired trajectory. The actor in this structure is a two layer feedforward neural network and the critic is a model of the cerebellum. The critic is trained by state-action-reward-state-action (SARSA) method. The critic will train the actor by supervisory learning based on the prior experiences. Simulation studies of oscillatory movements based on the proposed algorithm demonstrate excellent tracking capability and after 280 epochs the RMS error for position and velocity profiles were 0.02, 0.04 rad and rad/s, respectively.

  17. A point-to-point simple telehealth application for cardiovascular prevention: the ESINO LARIO experience. Cardiovascular prevention at point of care.

    Science.gov (United States)

    Malacarne, Mara; Gobbi, Giorgio; Pizzinelli, Paolo; Lesma, Alessandro; Castelli, Alberto; Lucini, Daniela; Pagani, Massimo

    2009-01-01

    Recent epidemiological evidence indicates that chronic degenerative diseases, notably cardiovascular, represent the major toll in terms of death and of impaired quality of life. Recent estimates indicate that a small increase in financial resources in a number of clinical cases may be sufficient to minimize the consequences of elevated cardiovascular risk per individual. The observation that lifestyle choices, and in particular increased physical exercise, might strongly impact cardiovascular risk, suggests a redesign of preventive strategies, based on the combination of pharmacological and behavioral interventions. Following our recent experience with the INteractive teleConsultation network for worldwide healthcAre Services (INCAS) system, we designed a simpler point-to-point telehealth infrastructure, to be employed in cardiovascular risk reduction programs, predicting a high level of acceptance from the population, at the cost of very limited investment. This model was tested on 181 subjects (ages 18-80 years) in the Italian mountain village of Esino Lario. These subjects underwent a screening test to evaluate arrhythmia and cardiometabolic risks (arrhythmias were found in 14% of subjects, systolic arterial pressure was observed in 43% of subjects above 140 mm Hg, diastolic arterial pressure in 31% above 90 mm Hg). This study demonstrates the feasibility of a scaled-down telehealth application particularly suited to cardiovascular prevention in remote areas, such as in mountain villages.

  18. Trajectory planning of mobile robots using indirect solution of optimal control method in generalized point-to-point task

    Science.gov (United States)

    Nazemizadeh, M.; Rahimi, H. N.; Amini Khoiy, K.

    2012-03-01

    This paper presents an optimal control strategy for optimal trajectory planning of mobile robots by considering nonlinear dynamic model and nonholonomic constraints of the system. The nonholonomic constraints of the system are introduced by a nonintegrable set of differential equations which represent kinematic restriction on the motion. The Lagrange's principle is employed to derive the nonlinear equations of the system. Then, the optimal path planning of the mobile robot is formulated as an optimal control problem. To set up the problem, the nonlinear equations of the system are assumed as constraints, and a minimum energy objective function is defined. To solve the problem, an indirect solution of the optimal control method is employed, and conditions of the optimality derived as a set of coupled nonlinear differential equations. The optimality equations are solved numerically, and various simulations are performed for a nonholonomic mobile robot to illustrate effectiveness of the proposed method.

  19. Hardware-assisted software clock synchronization for homogeneous distributed systems

    Science.gov (United States)

    Ramanathan, P.; Kandlur, Dilip D.; Shin, Kang G.

    1990-01-01

    A clock synchronization scheme that strikes a balance between hardware and software solutions is proposed. The proposed is a software algorithm that uses minimal additional hardware to achieve reasonably tight synchronization. Unlike other software solutions, the guaranteed worst-case skews can be made insensitive to the maximum variation of message transit delay in the system. The scheme is particularly suitable for large partially connected distributed systems with topologies that support simple point-to-point broadcast algorithms. Examples of such topologies include the hypercube and the mesh interconnection structures.

  20. Application of point-to-point matching algorithms for background correction in on-line liquid chromatography-Fourier transform infrared spectrometry (LC-FTIR).

    Science.gov (United States)

    Kuligowski, J; Quintás, G; Garrigues, S; de la Guardia, M

    2010-03-15

    A new background correction method for the on-line coupling of gradient liquid chromatography and Fourier transform infrared spectrometry has been developed. It is based on the use of a point-to-point matching algorithm that compares the absorption spectra of the sample data set with those of a previously recorded reference data set in order to select an appropriate reference spectrum. The spectral range used for the point-to-point comparison is selected with minimal user-interaction, thus facilitating considerably the application of the whole method. The background correction method has been successfully tested on a chromatographic separation of four nitrophenols running acetonitrile (0.08%, v/v TFA):water (0.08%, v/v TFA) gradients with compositions ranging from 35 to 85% (v/v) acetonitrile, giving accurate results for both, baseline resolved and overlapped peaks. Copyright (c) 2009 Elsevier B.V. All rights reserved.

  1. Distributed computer control system for reactor optimization

    International Nuclear Information System (INIS)

    Williams, A.H.

    1983-01-01

    At the Oldbury power station a prototype distributed computer control system has been installed. This system is designed to support research and development into improved reactor temperature control methods. This work will lead to the development and demonstration of new optimal control systems for improvement of plant efficiency and increase of generated output. The system can collect plant data from special test instrumentation connected to dedicated scanners and from the station's existing data processing system. The system can also, via distributed microprocessor-based interface units, make adjustments to the desired reactor channel gas exit temperatures. The existing control equipment will then adjust the height of control rods to maintain operation at these temperatures. The design of the distributed system is based on extensive experience with distributed systems for direct digital control, operator display and plant monitoring. The paper describes various aspects of this system, with particular emphasis on: (1) the hierarchal system structure; (2) the modular construction of the system to facilitate installation, commissioning and testing, and to reduce maintenance to module replacement; (3) the integration of the system into the station's existing data processing system; (4) distributed microprocessor-based interfaces to the reactor controls, with extensive security facilities implemented by hardware and software; (5) data transfer using point-to-point and bussed data links; (6) man-machine communication based on VDUs with computer input push-buttons and touch-sensitive screens; and (7) the use of a software system supporting a high-level engineer-orientated programming language, at all levels in the system, together with comprehensive data link management

  2. Drinking Water Distribution Systems

    Science.gov (United States)

    Learn about an overview of drinking water distribution systems, the factors that degrade water quality in the distribution system, assessments of risk, future research about these risks, and how to reduce cross-connection control risk.

  3. Providing full point-to-point communications among compute nodes of an operational group in a global combining network of a parallel computer

    Energy Technology Data Exchange (ETDEWEB)

    Archer, Charles J.; Faraj, Daniel A.; Inglett, Todd A.; Ratterman, Joseph D.

    2018-01-30

    Methods, apparatus, and products are disclosed for providing full point-to-point communications among compute nodes of an operational group in a global combining network of a parallel computer, each compute node connected to each adjacent compute node in the global combining network through a link, that include: receiving a network packet in a compute node, the network packet specifying a destination compute node; selecting, in dependence upon the destination compute node, at least one of the links for the compute node along which to forward the network packet toward the destination compute node; and forwarding the network packet along the selected link to the adjacent compute node connected to the compute node through the selected link.

  4. The Unidata LDM Data Distribution System

    Science.gov (United States)

    Emmerson, S.; Yoksas, T. C.; Weber, W. J.; Schmidt, M.

    2010-12-01

    The Unidata LDM is a near real-time, event-driven system for transmitting frequently-generated data-products, 24/7, from a producer to multiple subscribers using the Internet. Once received, a data-product is processed according to user specifications. A data-product can be anything up to 4 gigabytes in size. Downstream LDM-s register a regular expression based selection predicate with upstream LDM-s. Network topologies include point-to-point, star, and tree. Based on ONC RPC, the LDM system is extremely robust and efficient. Since its initial release in 1994, a network of LDM-s called the Internet Data Distribution (IDD) system has been the primary means by which many if not most Earth Sciences departments in the US obtain and process meteorological data (up to 20 GB/hour and 250k products/hour) with latencies measured in seconds or less. Data-products include numerical model output, radar data, WMO bulletins, and lightning data. Users of the LDM also include the international atmospheric science university community, NOAA, NASA, USGS, the US military, ECMWF, and the meteorological agencies of China, Australia, Brazil, South Korea, and Vietnam. The LDM is the highest volume advanced application on Internet-2 (currently averaging 27 terabytes per week). The LDM history and architecture is presented together with an analysis of its strengths and weaknesses.

  5. Smart Distribution Systems

    Directory of Open Access Journals (Sweden)

    Yazhou Jiang

    2016-04-01

    Full Text Available The increasing importance of system reliability and resilience is changing the way distribution systems are planned and operated. To achieve a distribution system self-healing against power outages, emerging technologies and devices, such as remote-controlled switches (RCSs and smart meters, are being deployed. The higher level of automation is transforming traditional distribution systems into the smart distribution systems (SDSs of the future. The availability of data and remote control capability in SDSs provides distribution operators with an opportunity to optimize system operation and control. In this paper, the development of SDSs and resulting benefits of enhanced system capabilities are discussed. A comprehensive survey is conducted on the state-of-the-art applications of RCSs and smart meters in SDSs. Specifically, a new method, called Temporal Causal Diagram (TCD, is used to incorporate outage notifications from smart meters for enhanced outage management. To fully utilize the fast operation of RCSs, the spanning tree search algorithm is used to develop service restoration strategies. Optimal placement of RCSs and the resulting enhancement of system reliability are discussed. Distribution system resilience with respect to extreme events is presented. Test cases are used to demonstrate the benefit of SDSs. Active management of distributed generators (DGs is introduced. Future research in a smart distribution environment is proposed.

  6. Low-current solutions for wireless point-to-point sensor data transmission for long-term applications; Stromsparende Loesungen fuer drahtlose Punkt-zu-Punkt-Sensordatenuebertragung fuer langjaehrigen Betrieb

    Energy Technology Data Exchange (ETDEWEB)

    Milosiu, H. [Fraunhofer-Institut fuer Integrierte Schaltungen IIS, Erlangen (Germany)

    2008-07-01

    Choosing wireless standard such as Bluetooth or Zigbee, the customer can find numerous low-cost chip sets. In particular applications proprietary solutions are superior to wireless standard solutions, especially for transmission of small data amounts from point to point. The complex transmission protocol of a wireless standard forms a inflexible precondition for the user and may exclude the choice of a wireless standard. In addition, a relatively high energy consumption disables battery-operated low-maintenance applications. Fraunhofer Institute for Integrated Circuits IIS in Erlangen now offers a solution to that problem. This article would like to show the benefits of low-current proprietary wireless systems. An implementation of a lowcurrent wireless system using BiCMOS technology for wireless sensor networks is presented. (orig.)

  7. Electric distribution systems

    CERN Document Server

    Sallam, A A

    2010-01-01

    "Electricity distribution is the penultimate stage in the delivery of electricity to end users. The only book that deals with the key topics of interest to distribution system engineers, Electric Distribution Systems presents a comprehensive treatment of the subject with an emphasis on both the practical and academic points of view. Reviewing traditional and cutting-edge topics, the text is useful to practicing engineers working with utility companies and industry, undergraduate graduate and students, and faculty members who wish to increase their skills in distribution system automation and monitoring."--

  8. Distributed Operating Systems

    NARCIS (Netherlands)

    Mullender, Sape J.

    1987-01-01

    In the past five years, distributed operating systems research has gone through a consolidation phase. On a large number of design issues there is now considerable consensus between different research groups. In this paper, an overview of recent research in distributed systems is given. In turn, the

  9. Pervasive Electricity Distribution System

    Directory of Open Access Journals (Sweden)

    Muhammad Usman Tahir

    2017-06-01

    Full Text Available Now a days a country cannot become economically strong until and unless it has enough electrical power to fulfil industrial and domestic needs. Electrical power being the pillar of any country’s economy, needs to be used in an efficient way. The same step is taken here by proposing a new system for energy distribution from substation to consumer houses, also it monitors the consumer consumption and record data. Unlike traditional manual Electrical systems, pervasive electricity distribution system (PEDS introduces a fresh perspective to monitor the feeder line status at distribution and consumer level. In this system an effort is taken to address the issues of electricity theft, manual billing, online monitoring of electrical distribution system and automatic control of electrical distribution points. The project is designed using microcontroller and different sensors, its GUI is designed in Labview software.

  10. Cooling water distribution system

    Science.gov (United States)

    Orr, Richard

    1994-01-01

    A passive containment cooling system for a nuclear reactor containment vessel. Disclosed is a cooling water distribution system for introducing cooling water by gravity uniformly over the outer surface of a steel containment vessel using an interconnected series of radial guide elements, a plurality of circumferential collector elements and collector boxes to collect and feed the cooling water into distribution channels extending along the curved surface of the steel containment vessel. The cooling water is uniformly distributed over the curved surface by a plurality of weirs in the distribution channels.

  11. Advanced Distribution Management System

    OpenAIRE

    Avazov, Artur; Sobinova, Lubov Anatolievna

    2016-01-01

    This article describes the advisability of using advanced distribution management systems in the electricity distribution networks area and considers premises of implementing ADMS within the Smart Grid era. Also, it gives the big picture of ADMS and discusses the ADMS advantages and functionalities.

  12. Advanced Distribution Management System

    Science.gov (United States)

    Avazov, Artur R.; Sobinova, Liubov A.

    2016-02-01

    This article describes the advisability of using advanced distribution management systems in the electricity distribution networks area and considers premises of implementing ADMS within the Smart Grid era. Also, it gives the big picture of ADMS and discusses the ADMS advantages and functionalities.

  13. Advanced Distribution Management System

    Directory of Open Access Journals (Sweden)

    Avazov Artur R.

    2016-01-01

    Full Text Available This article describes the advisability of using advanced distribution management systems in the electricity distribution networks area and considers premises of implementing ADMS within the Smart Grid era. Also, it gives the big picture of ADMS and discusses the ADMS advantages and functionalities.

  14. A distribution management system

    Energy Technology Data Exchange (ETDEWEB)

    Verho, P.; Jaerventausta, P.; Kaerenlampi, M.; Paulasaari, H. [Tampere Univ. of Technology (Finland); Partanen, J. [Lappeenranta Univ. of Technology (Finland)

    1996-12-31

    The development of new distribution automation applications is considerably wide nowadays. One of the most interesting areas is the development of a distribution management system (DMS) as an expansion of the traditional SCADA system. At the power transmission level such a system is called an energy management system (EMS). The idea of these expansions is to provide supporting tools for control center operators in system analysis and operation planning. The needed data for new applications is mainly available in some existing systems. Thus the computer systems of utilities must be integrated. The main data source for the new applications in the control center are the AM/FM/GIS (i.e. the network database system), the SCADA, and the customer information system (CIS). The new functions can be embedded in some existing computer system. This means a strong dependency on the vendor of the existing system. An alternative strategy is to develop an independent system which is integrated with other computer systems using well-defined interfaces. The latter approach makes it possible to use the new applications in various computer environments, having only a weak dependency on the vendors of the other systems. In the research project this alternative is preferred and used in developing an independent distribution management system

  15. A distribution management system

    Energy Technology Data Exchange (ETDEWEB)

    Verho, P; Jaerventausta, P; Kaerenlampi, M; Paulasaari, H [Tampere Univ. of Technology (Finland); Partanen, J [Lappeenranta Univ. of Technology (Finland)

    1997-12-31

    The development of new distribution automation applications is considerably wide nowadays. One of the most interesting areas is the development of a distribution management system (DMS) as an expansion of the traditional SCADA system. At the power transmission level such a system is called an energy management system (EMS). The idea of these expansions is to provide supporting tools for control center operators in system analysis and operation planning. The needed data for new applications is mainly available in some existing systems. Thus the computer systems of utilities must be integrated. The main data source for the new applications in the control center are the AM/FM/GIS (i.e. the network database system), the SCADA, and the customer information system (CIS). The new functions can be embedded in some existing computer system. This means a strong dependency on the vendor of the existing system. An alternative strategy is to develop an independent system which is integrated with other computer systems using well-defined interfaces. The latter approach makes it possible to use the new applications in various computer environments, having only a weak dependency on the vendors of the other systems. In the research project this alternative is preferred and used in developing an independent distribution management system

  16. A distribution management system

    Energy Technology Data Exchange (ETDEWEB)

    Jaerventausta, P; Verho, P; Kaerenlampi, M; Pitkaenen, M [Tampere Univ. of Technology (Finland); Partanen, J [Lappeenranta Univ. of Technology (Finland)

    1998-08-01

    The development of new distribution automation applications is considerably wide nowadays. One of the most interesting areas is the development of a distribution management system (DMS) as an expansion to the traditional SCADA system. At the power transmission level such a system is called an energy management system (EMS). The idea of these expansions is to provide supporting tools for control center operators in system analysis and operation planning. Nowadays the SCADA is the main computer system (and often the only) in the control center. However, the information displayed by the SCADA is often inadequate, and several tasks cannot be solved by a conventional SCADA system. A need for new computer applications in control center arises from the insufficiency of the SCADA and some other trends. The latter means that the overall importance of the distribution networks is increasing. The slowing down of load-growth has often made network reinforcements unprofitable. Thus the existing network must be operated more efficiently. At the same time larger distribution areas are for economical reasons being monitored at one control center and the size of the operation staff is decreasing. The quality of supply requirements are also becoming stricter. The needed data for new applications is mainly available in some existing systems. Thus the computer systems of utilities must be integrated. The main data source for the new applications in the control center are the AM/FM/GIS (i.e. the network database system), the SCADA, and the customer information system (CIS). The new functions can be embedded in some existing computer system. This means a strong dependency on the vendor of the existing system. An alternative strategy is to develop an independent system which is integrated with other computer systems using well-defined interfaces. The latter approach makes it possible to use the new applications in various computer environments, having only a weak dependency on the

  17. Distributed processor systems

    International Nuclear Information System (INIS)

    Zacharov, B.

    1976-01-01

    In recent years, there has been a growing tendency in high-energy physics and in other fields to solve computational problems by distributing tasks among the resources of inter-coupled processing devices and associated system elements. This trend has gained further momentum more recently with the increased availability of low-cost processors and with the development of the means of data distribution. In two lectures, the broad question of distributed computing systems is examined and the historical development of such systems reviewed. An attempt is made to examine the reasons for the existence of these systems and to discern the main trends for the future. The components of distributed systems are discussed in some detail and particular emphasis is placed on the importance of standards and conventions in certain key system components. The ideas and principles of distributed systems are discussed in general terms, but these are illustrated by a number of concrete examples drawn from the context of the high-energy physics environment. (Auth.)

  18. Distributed Treatment Systems.

    Science.gov (United States)

    Zgonc, David; Plante, Luke

    2017-10-01

    This section presents a review of the literature published in 2016 on topics relating to distributed treatment systems. This review is divided into the following sections with multiple subsections under each: constituent removal; treatment technologies; and planning and treatment system management.

  19. Distributed Computerized Catalog System

    Science.gov (United States)

    Borgen, Richard L.; Wagner, David A.

    1995-01-01

    DarkStar Distributed Catalog System describes arbitrary data objects in unified manner, providing end users with versatile, yet simple search mechanism for locating and identifying objects. Provides built-in generic and dynamic graphical user interfaces. Design of system avoids some of problems of standard DBMS, and system provides more flexibility than do conventional relational data bases, or object-oriented data bases. Data-collection lattice partly hierarchical representation of relationships among collections, subcollections, and data objects.

  20. A distributed name resolution system in information centric networks

    Science.gov (United States)

    Elbreiki, Walid; Arlimatti, Shivaleela; Hassan, Suhaidi; Habbal, Adib; Elshaikh, Mohamed

    2016-08-01

    Information Centric Networks (ICN) is the new paradigm that envisages to shift the Internet away from its existing Point-to-Point architecture to a data centric, where communication is based on named hosts rather than the information stored on these hosts. Name Resolution is the center of attraction for ICN, where Named Data Objects (NDO) are used for identifying the information and guiding for routing or forwarding inside ICN. Recently, several researches use distributed NRS to overcome the problem of interest flooding, congestion and overloading. Yet the distribution of NRS is based on random distribution. How to distribute the NRS is still an important and challenging problem. In this work, we address the problem of distribution of NRS by proposing a new mechanism called Distributed Name Resolution System (DNRS), by considering the time of publishing the NDOs in the NRS. This mechanism partitions the network to distribute the workload among NRSs by increasing storage capacity. In addition, partitioning the network increases flexibility and scalability of NRS. We evaluate the effectiveness of our proposed mechanism, which achieves lesser end-to-end delay with more average throughputs compared to random distribution of NRS without disturbing the underlying routing or forwarding strategies.

  1. Optimizing electrical distribution systems

    International Nuclear Information System (INIS)

    Scott, W.G.

    1990-01-01

    Electrical utility distribution systems are in the middle of an unprecedented technological revolution in planning, design, maintenance and operation. The prime movers of the revolution are the major economic shifts that affect decision making. The major economic influence on the revolution is the cost of losses (technical and nontechnical). The vehicle of the revolution is the computer, which enables decision makers to examine alternatives in greater depth and detail than their predecessors could. The more important elements of the technological revolution are: system planning, computers, load forecasting, analytical systems (primary systems, transformers and secondary systems), system losses and coming technology. The paper is directed towards the rather unique problems encountered by engineers of utilities in developing countries - problems that are being solved through high technology, such as the recent World Bank-financed engineering computer system for Sri Lanka. This system includes a DEC computer, digitizer, plotter and engineering software to model the distribution system via a digitizer, analyse the system and plot single-line diagrams. (author). 1 ref., 4 tabs., 6 figs

  2. Distributed Systems 3/e

    NARCIS (Netherlands)

    Tanenbaum, A.S.; van Steen, M.R.

    2016-01-01

    For this third edition of "Distributed Systems," the material has been thoroughly revised and extended, integrating principles and paradigms into nine chapters: 1. Introduction 2. Architectures 3. Processes 4. Communication 5. Naming 6. Coordination 7. Replication 8. Fault tolerance 9. Security A

  3. Distributed Optimization System

    Science.gov (United States)

    Hurtado, John E.; Dohrmann, Clark R.; Robinett, III, Rush D.

    2004-11-30

    A search system and method for controlling multiple agents to optimize an objective using distributed sensing and cooperative control. The search agent can be one or more physical agents, such as a robot, and can be software agents for searching cyberspace. The objective can be: chemical sources, temperature sources, radiation sources, light sources, evaders, trespassers, explosive sources, time dependent sources, time independent sources, function surfaces, maximization points, minimization points, and optimal control of a system such as a communication system, an economy, a crane, and a multi-processor computer.

  4. Distributed Data Management and Distributed File Systems

    CERN Document Server

    Girone, Maria

    2015-01-01

    The LHC program has been successful in part due to the globally distributed computing resources used for collecting, serving, processing, and analyzing the large LHC datasets. The introduction of distributed computing early in the LHC program spawned the development of new technologies and techniques to synchronize information and data between physically separated computing centers. Two of the most challenges services are the distributed file systems and the distributed data management systems. In this paper I will discuss how we have evolved from local site services to more globally independent services in the areas of distributed file systems and data management and how these capabilities may continue to evolve into the future. I will address the design choices, the motivations, and the future evolution of the computing systems used for High Energy Physics.

  5. Distributed System Design Checklist

    Science.gov (United States)

    Hall, Brendan; Driscoll, Kevin

    2014-01-01

    This report describes a design checklist targeted to fault-tolerant distributed electronic systems. Many of the questions and discussions in this checklist may be generally applicable to the development of any safety-critical system. However, the primary focus of this report covers the issues relating to distributed electronic system design. The questions that comprise this design checklist were created with the intent to stimulate system designers' thought processes in a way that hopefully helps them to establish a broader perspective from which they can assess the system's dependability and fault-tolerance mechanisms. While best effort was expended to make this checklist as comprehensive as possible, it is not (and cannot be) complete. Instead, we expect that this list of questions and the associated rationale for the questions will continue to evolve as lessons are learned and further knowledge is established. In this regard, it is our intent to post the questions of this checklist on a suitable public web-forum, such as the NASA DASHLink AFCS repository. From there, we hope that it can be updated, extended, and maintained after our initial research has been completed.

  6. Electrical distribution system management

    International Nuclear Information System (INIS)

    Hajos, L.; Mortarulo, M.; Chang, K.; Sparks, T.

    1990-01-01

    This paper reports that maintenance of electrical system data is essential to the operation, maintenance, and modification of a nuclear station. Load and equipment changes affect equipment sizing, available short-circuit currents and protection coordination. System parameters must be maintained in a controlled manner to enable evaluation of proposed modifications and provide adequate verification and traceability. For this purpose, Public Service Electric and Gas Company has implemented a Verified and Validated Electric Distribution System Management (EDSM) program at the Hope Creek and Salem Nuclear Power Stations. EDSM program integrates computerized configuration management of electrical systems with calculational software the Technical Standard procedures. The software platform is PC-based. The Database Manager and Calculational programs have been linked together through a user friendly menu system. The database management nodule enable s assembly and maintenance of databases for individual loads, buses, and branches within the electrical systems with system access and approval controlled through electronic security incorporated within the database manger. Reports drawn from the database serve as the as-built and/or as-designed record of the system configurations. This module also creates input data files of network parameters in a format readable by the calculational modules. Calculations modules provide load flow, voltage drop, motor starting, and short-circuit analyses, as well as dynamic analyses of bus transfers

  7. Planning Systems for Distributed Operations

    Science.gov (United States)

    Maxwell, Theresa G.

    2002-01-01

    This viewgraph representation presents an overview of the mission planning process involving distributed operations (such as the International Space Station (ISS)) and the computer hardware and software systems needed to support such an effort. Topics considered include: evolution of distributed planning systems, ISS distributed planning, the Payload Planning System (PPS), future developments in distributed planning systems, Request Oriented Scheduling Engine (ROSE) and Next Generation distributed planning systems.

  8. Managing Distributed Knowledge Systems

    DEFF Research Database (Denmark)

    Sørensen, Brian Vejrum; Gelbuda, Modestas

    2005-01-01

    . This paper contributes to the research on organizations as distributed knowledge systems by addressing two weaknesses of the social practice literature. Firstly, it downplays the importance of formal structure and organizational design and intervention efforts by key organizational members. Secondly, it does......The article argues that the growth of de novo knowledge-based organization depends on managing and coordinating increasingly growing and, therefore, distributed knowledge. Moreover, the growth in knowledge is often accompanied by an increasing organizational complexity, which is a result...... of integrating new people, building new units and adding activities to the existing organization. It is argued that knowledge is not a stable capacity that belongs to any actor alone, but that it is rather an ongoing social accomplishment, which is created and recreated as actors engage in mutual activities...

  9. Distributed road assessment system

    Science.gov (United States)

    Beer, N. Reginald; Paglieroni, David W

    2014-03-25

    A system that detects damage on or below the surface of a paved structure or pavement is provided. A distributed road assessment system includes road assessment pods and a road assessment server. Each road assessment pod includes a ground-penetrating radar antenna array and a detection system that detects road damage from the return signals as the vehicle on which the pod is mounted travels down a road. Each road assessment pod transmits to the road assessment server occurrence information describing each occurrence of road damage that is newly detected on a current scan of a road. The road assessment server maintains a road damage database of occurrence information describing the previously detected occurrences of road damage. After the road assessment server receives occurrence information for newly detected occurrences of road damage for a portion of a road, the road assessment server determines which newly detected occurrences correspond to which previously detected occurrences of road damage.

  10. Communication Facilities for Distributed Systems

    Directory of Open Access Journals (Sweden)

    V. Barladeanu

    1997-01-01

    Full Text Available The design of physical networks and communication protocols in Distributed Systems can have a direct impact on system efficiency and reliability. This paper tries to identify efficient mechanisms and paradigms for communication in distributed systems.

  11. Optimizing queries in distributed systems

    Directory of Open Access Journals (Sweden)

    Ion LUNGU

    2006-01-01

    Full Text Available This research presents the main elements of query optimizations in distributed systems. First, data architecture according with system level architecture in a distributed environment is presented. Then the architecture of a distributed database management system (DDBMS is described on conceptual level followed by the presentation of the distributed query execution steps on these information systems. The research ends with presentation of some aspects of distributed database query optimization and strategies used for that.

  12. Quality monitored distributed voting system

    Science.gov (United States)

    Skogmo, David

    1997-01-01

    A quality monitoring system can detect certain system faults and fraud attempts in a distributed voting system. The system uses decoy voters to cast predetermined check ballots. Absent check ballots can indicate system faults. Altered check ballots can indicate attempts at counterfeiting votes. The system can also cast check ballots at predetermined times to provide another check on the distributed voting system.

  13. Process evaluation distributed system

    Science.gov (United States)

    Moffatt, Christopher L. (Inventor)

    2006-01-01

    The distributed system includes a database server, an administration module, a process evaluation module, and a data display module. The administration module is in communication with the database server for providing observation criteria information to the database server. The process evaluation module is in communication with the database server for obtaining the observation criteria information from the database server and collecting process data based on the observation criteria information. The process evaluation module utilizes a personal digital assistant (PDA). A data display module in communication with the database server, including a website for viewing collected process data in a desired metrics form, the data display module also for providing desired editing and modification of the collected process data. The connectivity established by the database server to the administration module, the process evaluation module, and the data display module, minimizes the requirement for manual input of the collected process data.

  14. Distributed security in closed distributed systems

    DEFF Research Database (Denmark)

    Hernandez, Alejandro Mario

    properties. This is also restricted to distributed systems in which the set of locations is known a priori. All this follows techniques borrowed from both the model checking and the static analysis communities. In the end, we reach a step towards solving the problem of enforcing security in distributed...... systems. We achieve the goal of showing how this can be done, though we restrict ourselves to closed systems and with a limited set of enforceable security policies. In this setting, our approach proves to be efficient. Finally, we achieve all this by bringing together several fields of Computer Science......The goal of the present thesis is to discuss, argue and conclude about ways to provide security to the information travelling around computer systems consisting of several known locations. When developing software systems, security of the information managed by these plays an important role...

  15. Distribution System Pricing with Distributed Energy Resources

    Energy Technology Data Exchange (ETDEWEB)

    Hledik, Ryan [The Brattle Group, Cambridge, MA (United States); Lazar, Jim [The Regulatory Assistance Project, Montpelier, VT (United States); Schwartz, Lisa [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2017-08-16

    Technological changes in the electric utility industry bring tremendous opportunities and significant challenges. Customers are installing clean sources of on-site generation such as rooftop solar photovoltaic (PV) systems. At the same time, smart appliances and control systems that can communicate with the grid are entering the retail market. Among the opportunities these changes create are a cleaner and more diverse power system, the ability to improve system reliability and system resilience, and the potential for lower total costs. Challenges include integrating these new resources in a way that maintains system reliability, provides an equitable sharing of system costs, and avoids unbalanced impacts on different groups of customers, including those who install distributed energy resources (DERs) and low-income households who may be the least able to afford the transition.

  16. RBAC Administration in Distributed Systems

    NARCIS (Netherlands)

    Dekker, M.A.C.; Crampton, J.; Etalle, Sandro

    2007-01-01

    Despite a large body of literature on the administration of RBAC policies in centralized systems, the problem of the administration of a distributed system has hardly been addressed. We present a formal system for modelling a distributed RBAC system and its administration. We define two basic

  17. Distribution system modeling and analysis

    CERN Document Server

    Kersting, William H

    2001-01-01

    For decades, distribution engineers did not have the sophisticated tools developed for analyzing transmission systems-often they had only their instincts. Things have changed, and we now have computer programs that allow engineers to simulate, analyze, and optimize distribution systems. Powerful as these programs are, however, without a real understanding of the operating characteristics of a distribution system, engineers using the programs can easily make serious errors in their designs and operating procedures. Distribution System Modeling and Analysis helps prevent those errors. It gives readers a basic understanding of the modeling and operating characteristics of the major components of a distribution system. One by one, the author develops and analyzes each component as a stand-alone element, then puts them all together to analyze a distribution system comprising the various shunt and series devices for power-flow and short-circuit studies. He includes the derivation of all models and includes many num...

  18. Distributed systems status and control

    Science.gov (United States)

    Kreidler, David; Vickers, David

    1990-01-01

    Concepts are investigated for an automated status and control system for a distributed processing environment. System characteristics, data requirements for health assessment, data acquisition methods, system diagnosis methods and control methods were investigated in an attempt to determine the high-level requirements for a system which can be used to assess the health of a distributed processing system and implement control procedures to maintain an accepted level of health for the system. A potential concept for automated status and control includes the use of expert system techniques to assess the health of the system, detect and diagnose faults, and initiate or recommend actions to correct the faults. Therefore, this research included the investigation of methods by which expert systems were developed for real-time environments and distributed systems. The focus is on the features required by real-time expert systems and the tools available to develop real-time expert systems.

  19. Water Treatment Technology - Distribution Systems.

    Science.gov (United States)

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on distribution systems provides instructional materials for six competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: types of pipe for distribution systems, types…

  20. The THUDSOS Distributed Operating System

    Institute of Scientific and Technical Information of China (English)

    廖先Zhi; 刘旭峰; 等

    1991-01-01

    The THUDSOS is a distributed operating system modeled as an abstract machine which provides decentralized control,transparency,availability,and reliability,as welol as a good degree of autonomy at each node,that makes our distributed system usable.Our operating system supports transparent access to data through network wide filesystem.The simultaneous access to any device is discussed for the case when the peripherals are treated as files.This operating system allows spawning of parallel application programs to solve problems in the fields,such as numerical analysis and artificial intelligence.

  1. Energy efficient distributed computing systems

    CERN Document Server

    Lee, Young-Choon

    2012-01-01

    The energy consumption issue in distributed computing systems raises various monetary, environmental and system performance concerns. Electricity consumption in the US doubled from 2000 to 2005.  From a financial and environmental standpoint, reducing the consumption of electricity is important, yet these reforms must not lead to performance degradation of the computing systems.  These contradicting constraints create a suite of complex problems that need to be resolved in order to lead to 'greener' distributed computing systems.  This book brings together a group of outsta

  2. Coordination control of distributed systems

    CERN Document Server

    Villa, Tiziano

    2015-01-01

    This book describes how control of distributed systems can be advanced by an integration of control, communication, and computation. The global control objectives are met by judicious combinations of local and nonlocal observations taking advantage of various forms of communication exchanges between distributed controllers. Control architectures are considered according to  increasing degrees of cooperation of local controllers:  fully distributed or decentralized control,  control with communication between controllers,  coordination control, and multilevel control.  The book covers also topics bridging computer science, communication, and control, like communication for control of networks, average consensus for distributed systems, and modeling and verification of discrete and of hybrid systems. Examples and case studies are introduced in the first part of the text and developed throughout the book. They include: control of underwater vehicles, automated-guided vehicles on a container terminal, contro...

  3. RBAC administration in distributed systems

    NARCIS (Netherlands)

    Dekker, M.A.C.; Crampton, J.; Etalle, Sandro; Li, N.

    Large and distributed access control systems are increasingly common, for example in health care. In such settings, access control policies may become very complex, thus complicating correct and efficient adminstration of the access control system. Despite being one of the most widely used access

  4. Systems Measures of Water Distribution System Resilience

    Energy Technology Data Exchange (ETDEWEB)

    Klise, Katherine A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Murray, Regan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Walker, La Tonya Nicole [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-01-01

    Resilience is a concept that is being used increasingly to refer to the capacity of infrastructure systems to be prepared for and able to respond effectively and rapidly to hazardous events. In Section 2 of this report, drinking water hazards, resilience literature, and available resilience tools are presented. Broader definitions, attributes and methods for measuring resilience are presented in Section 3. In Section 4, quantitative systems performance measures for water distribution systems are presented. Finally, in Section 5, the performance measures and their relevance to measuring the resilience of water systems to hazards is discussed along with needed improvements to water distribution system modeling tools.

  5. THE FRANCHISE SYSTEM OF DISTRIBUTION.

    Science.gov (United States)

    The working relationships between franchise companies and their franchised dealers are analyzed. The benefits derived from the use of a franchisesise...system of distribution for both the franchisor and franchisee are determined. The principal problems encountered by the parties to the franchise ...agreement are isolated, and this method of distribution is evaluated from the standpoint of both the franchise company and franchised dealers and to assess its impact on the marketing economy of the nation.

  6. Maintaining consistency in distributed systems

    Science.gov (United States)

    Birman, Kenneth P.

    1991-01-01

    In systems designed as assemblies of independently developed components, concurrent access to data or data structures normally arises within individual programs, and is controlled using mutual exclusion constructs, such as semaphores and monitors. Where data is persistent and/or sets of operation are related to one another, transactions or linearizability may be more appropriate. Systems that incorporate cooperative styles of distributed execution often replicate or distribute data within groups of components. In these cases, group oriented consistency properties must be maintained, and tools based on the virtual synchrony execution model greatly simplify the task confronting an application developer. All three styles of distributed computing are likely to be seen in future systems - often, within the same application. This leads us to propose an integrated approach that permits applications that use virtual synchrony with concurrent objects that respect a linearizability constraint, and vice versa. Transactional subsystems are treated as a special case of linearizability.

  7. Distribution network strengthens sales systems

    International Nuclear Information System (INIS)

    Janoska, J.

    2003-01-01

    Liberalisation of the electricity market pushes Slovak distribution companies to upgrade their sale technologies. The first one to invest into a complex electronic sales system will be Stredoslovenska energetika, a.s., Zilina. The system worth 200 million Sk (4,83 million Euro) will be supplied by Polish software company Winuel. The company should also supply a software that would allow forecasting and planning of sales. The system should be fully operational by 2006. TREND has not managed to obtain information regarding plans Zapadoslovenska energetika - the largest and most active distribution company - might have in this area. In eastern Slovakia distribution company Vychodoslovenska energetika, a.s., Kosice has also started addressing this issue. (Author)

  8. Compressed sensing for distributed systems

    CERN Document Server

    Coluccia, Giulio; Magli, Enrico

    2015-01-01

    This book presents a survey of the state-of-the art in the exciting and timely topic of compressed sensing for distributed systems. It has to be noted that, while compressed sensing has been studied for some time now, its distributed applications are relatively new. Remarkably, such applications are ideally suited to exploit all the benefits that compressed sensing can provide. The objective of this book is to provide the reader with a comprehensive survey of this topic, from the basic concepts to different classes of centralized and distributed reconstruction algorithms, as well as a comparison of these techniques. This book collects different contributions on these aspects. It presents the underlying theory in a complete and unified way for the first time, presenting various signal models and their use cases. It contains a theoretical part collecting latest results in rate-distortion analysis of distributed compressed sensing, as well as practical implementations of algorithms obtaining performance close to...

  9. Enhanced distributed energy resource system

    Science.gov (United States)

    Atcitty, Stanley [Albuquerque, NM; Clark, Nancy H [Corrales, NM; Boyes, John D [Albuquerque, NM; Ranade, Satishkumar J [Las Cruces, NM

    2007-07-03

    A power transmission system including a direct current power source electrically connected to a conversion device for converting direct current into alternating current, a conversion device connected to a power distribution system through a junction, an energy storage device capable of producing direct current connected to a converter, where the converter, such as an insulated gate bipolar transistor, converts direct current from an energy storage device into alternating current and supplies the current to the junction and subsequently to the power distribution system. A microprocessor controller, connected to a sampling and feedback module and the converter, determines when the current load is higher than a set threshold value, requiring triggering of the converter to supply supplemental current to the power transmission system.

  10. Distributed Supervisory Protection Interlock System

    International Nuclear Information System (INIS)

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

    1989-03-01

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

  11. Distributed Systems: The Hard Problems

    CERN Multimedia

    CERN. Geneva

    2015-01-01

    **Nicholas Bellerophon** works as a client services engineer at Basho Technologies, helping customers setup and run distributed systems at scale in the wild. He has also worked in massively multiplayer games, and recently completed a live scalable simulation engine. He is an avid TED-watcher with interests in many areas of the arts, science, and engineering, including of course high-energy physics.

  12. Distribution system analysis and automation

    CERN Document Server

    Gers, Juan

    2013-01-01

    A comprehensive guide to techniques that allow engineers to simulate, analyse and optimise power distribution systems which combined with automation, underpin the emerging concept of the "smart grid". This book is supported by theoretical concepts with real-world applications and MATLAB exercises.

  13. Turboelectric Distributed Propulsion System Modelling

    OpenAIRE

    Liu, Chengyuan

    2013-01-01

    The Blended-Wing-Body is a conceptual aircraft design with rear-mounted, over wing engines. Turboelectric distributed propulsion system with boundary layer ingestion has been considered for this aircraft. It uses electricity to transmit power from the core turbine to the fans, therefore dramatically increases bypass ratio to reduce fuel consumption and noise. This dissertation presents methods on designing the TeDP system, evaluating effects of boundary layer ingestion, modelling engine perfo...

  14. A Distributed User Information System

    Science.gov (United States)

    1990-03-01

    NOE08 Department of Computer Science NOVO 8 1990 University of Maryland S College Park, MD 20742 D Abstract Current user information database technology ...Transactions on Computer Systems, May 1988. [So189] K. Sollins. A plan for internet directory services. Technical report, DDN Network Information Center...2424 A Distributed User Information System DTiC Steven D. Miller, Scott Carson, and Leo Mark DELECTE Institute for Advanced Computer Studies and

  15. The ATLAS distributed analysis system

    International Nuclear Information System (INIS)

    Legger, F

    2014-01-01

    In the LHC operations era, analysis of the multi-petabyte ATLAS data sample by globally distributed physicists is a challenging task. To attain the required scale the ATLAS Computing Model was designed around the concept of Grid computing, realized in the Worldwide LHC Computing Grid (WLCG), the largest distributed computational resource existing in the sciences. The ATLAS experiment currently stores over 140 PB of data and runs about 140,000 concurrent jobs continuously at WLCG sites. During the first run of the LHC, the ATLAS Distributed Analysis (DA) service has operated stably and scaled as planned. More than 1600 users submitted jobs in 2012, with 2 million or more analysis jobs per week, peaking at about a million jobs per day. The system dynamically distributes popular data to expedite processing and maximally utilize resources. The reliability of the DA service is high and steadily improving; Grid sites are continually validated against a set of standard tests, and a dedicated team of expert shifters provides user support and communicates user problems to the sites. Both the user support techniques and the direct feedback of users have been effective in improving the success rate and user experience when utilizing the distributed computing environment. In this contribution a description of the main components, activities and achievements of ATLAS distributed analysis is given. Several future improvements being undertaken will be described.

  16. The ATLAS distributed analysis system

    Science.gov (United States)

    Legger, F.; Atlas Collaboration

    2014-06-01

    In the LHC operations era, analysis of the multi-petabyte ATLAS data sample by globally distributed physicists is a challenging task. To attain the required scale the ATLAS Computing Model was designed around the concept of Grid computing, realized in the Worldwide LHC Computing Grid (WLCG), the largest distributed computational resource existing in the sciences. The ATLAS experiment currently stores over 140 PB of data and runs about 140,000 concurrent jobs continuously at WLCG sites. During the first run of the LHC, the ATLAS Distributed Analysis (DA) service has operated stably and scaled as planned. More than 1600 users submitted jobs in 2012, with 2 million or more analysis jobs per week, peaking at about a million jobs per day. The system dynamically distributes popular data to expedite processing and maximally utilize resources. The reliability of the DA service is high and steadily improving; Grid sites are continually validated against a set of standard tests, and a dedicated team of expert shifters provides user support and communicates user problems to the sites. Both the user support techniques and the direct feedback of users have been effective in improving the success rate and user experience when utilizing the distributed computing environment. In this contribution a description of the main components, activities and achievements of ATLAS distributed analysis is given. Several future improvements being undertaken will be described.

  17. Distributed optimization system and method

    Science.gov (United States)

    Hurtado, John E.; Dohrmann, Clark R.; Robinett, III, Rush D.

    2003-06-10

    A search system and method for controlling multiple agents to optimize an objective using distributed sensing and cooperative control. The search agent can be one or more physical agents, such as a robot, and can be software agents for searching cyberspace. The objective can be: chemical sources, temperature sources, radiation sources, light sources, evaders, trespassers, explosive sources, time dependent sources, time independent sources, function surfaces, maximization points, minimization points, and optimal control of a system such as a communication system, an economy, a crane, and a multi-processor computer.

  18. World-wide distribution automation systems

    International Nuclear Information System (INIS)

    Devaney, T.M.

    1994-01-01

    A worldwide power distribution automation system is outlined. Distribution automation is defined and the status of utility automation is discussed. Other topics discussed include a distribution management system, substation feeder, and customer functions, potential benefits, automation costs, planning and engineering considerations, automation trends, databases, system operation, computer modeling of system, and distribution management systems

  19. Distributed Persistent Identifiers System Design

    Directory of Open Access Journals (Sweden)

    Pavel Golodoniuc

    2017-06-01

    Full Text Available The need to identify both digital and physical objects is ubiquitous in our society. Past and present persistent identifier (PID systems, of which there is a great variety in terms of technical and social implementation, have evolved with the advent of the Internet, which has allowed for globally unique and globally resolvable identifiers. PID systems have, by in large, catered for identifier uniqueness, integrity, and persistence, regardless of the identifier’s application domain. Trustworthiness of these systems has been measured by the criteria first defined by Bütikofer (2009 and further elaborated by Golodoniuc 'et al'. (2016 and Car 'et al'. (2017. Since many PID systems have been largely conceived and developed by a single organisation they faced challenges for widespread adoption and, most importantly, the ability to survive change of technology. We believe that a cause of PID systems that were once successful fading away is the centralisation of support infrastructure – both organisational and computing and data storage systems. In this paper, we propose a PID system design that implements the pillars of a trustworthy system – ensuring identifiers’ independence of any particular technology or organisation, implementation of core PID system functions, separation from data delivery, and enabling the system to adapt for future change. We propose decentralisation at all levels — persistent identifiers and information objects registration, resolution, and data delivery — using Distributed Hash Tables and traditional peer-to-peer networks with information replication and caching mechanisms, thus eliminating the need for a central PID data store. This will increase overall system fault tolerance thus ensuring its trustworthiness. We also discuss important aspects of the distributed system’s governance, such as the notion of the authoritative source and data integrity

  20. Distributed hierarchical radiation monitoring system

    International Nuclear Information System (INIS)

    Barak, D.

    1985-01-01

    A solution to the problem of monitoring the radiation levels in and around a nuclear facility is presented in this paper. This is a private case of a large scale general purpose data acqisition system with high reliability, availability and short maintenance time. The physical layout of the detectors in the plant, and the strict control demands dictated a distributed and hierarchical system. The system is comprised of three levels, each level contains modules. Level one contains the Control modules which collects data from groups of detectors and executes emergency local control tasks. In level two are the Group controllers which concentrate data from the Control modules, and enable local display and communication. The system computer is in level three, enabling the plant operator to receive information from the detectors and execute control tasks. The described system was built and is operating successfully for about two years. (author)

  1. The ATLAS Distributed Analysis System

    CERN Document Server

    Legger, F; The ATLAS collaboration; Pacheco Pages, A; Stradling, A

    2013-01-01

    In the LHC operations era, analysis of the multi-petabyte ATLAS data sample by globally distributed physicists is a challenging task. To attain the required scale the ATLAS Computing Model was designed around the concept of grid computing, realized in the Worldwide LHC Computing Grid (WLCG), the largest distributed computational resource existing in the sciences. The ATLAS experiment currently stores over 140 PB of data and runs about 140,000 concurrent jobs continuously at WLCG sites. During the first run of the LHC, the ATLAS Distributed Analysis (DA) service has operated stably and scaled as planned. More than 1600 users submitted jobs in 2012, with 2 million or more analysis jobs per week, peaking at about a million jobs per day. The system dynamically distributes popular data to expedite processing and maximally utilize resources. The reliability of the DA service is high but steadily improving; grid sites are continually validated against a set of standard tests, and a dedicated team of expert shifters ...

  2. The ATLAS Distributed Analysis System

    CERN Document Server

    Legger, F; The ATLAS collaboration

    2014-01-01

    In the LHC operations era, analysis of the multi-petabyte ATLAS data sample by globally distributed physicists is a challenging task. To attain the required scale the ATLAS Computing Model was designed around the concept of grid computing, realized in the Worldwide LHC Computing Grid (WLCG), the largest distributed computational resource existing in the sciences. The ATLAS experiment currently stores over 140 PB of data and runs about 140,000 concurrent jobs continuously at WLCG sites. During the first run of the LHC, the ATLAS Distributed Analysis (DA) service has operated stably and scaled as planned. More than 1600 users submitted jobs in 2012, with 2 million or more analysis jobs per week, peaking at about a million jobs per day. The system dynamically distributes popular data to expedite processing and maximally utilize resources. The reliability of the DA service is high but steadily improving; grid sites are continually validated against a set of standard tests, and a dedicated team of expert shifters ...

  3. Distributed optimal coordination for distributed energy resources in power systems

    DEFF Research Database (Denmark)

    Wu, Di; Yang, Tao; Stoorvogel, A.

    2017-01-01

    Driven by smart grid technologies, distributed energy resources (DERs) have been rapidly developing in recent years for improving reliability and efficiency of distribution systems. Emerging DERs require effective and efficient coordination in order to reap their potential benefits. In this paper......, we consider an optimal DER coordination problem over multiple time periods subject to constraints at both system and device levels. Fully distributed algorithms are proposed to dynamically and automatically coordinate distributed generators with multiple/single storages. With the proposed algorithms...

  4. Small Aircraft Data Distribution System

    Science.gov (United States)

    Chazanoff, Seth L.; Dinardo, Steven J.

    2012-01-01

    The CARVE Small Aircraft Data Distribution System acquires the aircraft location and attitude data that is required by the various programs running on a distributed network. This system distributes the data it acquires to the data acquisition programs for inclusion in their data files. It uses UDP (User Datagram Protocol) to broadcast data over a LAN (Local Area Network) to any programs that might have a use for the data. The program is easily adaptable to acquire additional data and log that data to disk. The current version also drives displays using precision pitch and roll information to aid the pilot in maintaining a level-level attitude for radar/radiometer mapping beyond the degree available by flying visually or using a standard gyro-driven attitude indicator. The software is designed to acquire an array of data to help the mission manager make real-time decisions as to the effectiveness of the flight. This data is displayed for the mission manager and broadcast to the other experiments on the aircraft for inclusion in their data files. The program also drives real-time precision pitch and roll displays for the pilot and copilot to aid them in maintaining the desired attitude, when required, during data acquisition on mapping lines.

  5. Video distribution system cost model

    Science.gov (United States)

    Gershkoff, I.; Haspert, J. K.; Morgenstern, B.

    1980-01-01

    A cost model that can be used to systematically identify the costs of procuring and operating satellite linked communications systems is described. The user defines a network configuration by specifying the location of each participating site, the interconnection requirements, and the transmission paths available for the uplink (studio to satellite), downlink (satellite to audience), and voice talkback (between audience and studio) segments of the network. The model uses this information to calculate the least expensive signal distribution path for each participating site. Cost estimates are broken downy by capital, installation, lease, operations and maintenance. The design of the model permits flexibility in specifying network and cost structure.

  6. Distribution system protection with communication technologies

    DEFF Research Database (Denmark)

    Wei, Mu; Chen, Zhe

    2010-01-01

    Due to the communication technologies’ involvement in the distribution power system, the time-critical protection function may be implemented more accurately, therefore distribution power systems’ stability, reliability and security could be improved. This paper presents an active distribution...

  7. Loss Allocation in a Distribution System with Distributed Generation Units

    DEFF Research Database (Denmark)

    Lund, Torsten; Nielsen, Arne Hejde; Sørensen, Poul Ejnar

    2007-01-01

    In Denmark, a large part of the electricity is produced by wind turbines and combined heat and power plants (CHPs). Most of them are connected to the network through distribution systems. This paper presents a new algorithm for allocation of the losses in a distribution system with distributed...... generation. The algorithm is based on a reduced impedance matrix of the network and current injections from loads and production units. With the algorithm, the effect of the covariance between production and consumption can be evaluated. To verify the theoretical results, a model of the distribution system...

  8. Quantum distribution function of nonequilibrium system

    International Nuclear Information System (INIS)

    Sogo, Kiyoshi; Fujimoto, Yasushi.

    1990-03-01

    A path integral representation is derived for the Wigner distribution function of a nonequilibrium system coupled with heat bath. Under appropriate conditions, the Wigner distribution function approaches an equilibrium distribution, which manifests shifting and broadening of spectral lines due to the interaction with heat bath. It is shown that the equilibrium distribution becomes the quantum canonical distribution in the vanishing coupling constant limit. (author)

  9. The Planetary Data System Distributed Inventory System

    Science.gov (United States)

    Hughes, J. Steven; McMahon, Susan K.

    1996-01-01

    The advent of the World Wide Web (Web) and the ability to easily put data repositories on-line has resulted in a proliferation of digital libraries. The heterogeneity of the underlying systems, the autonomy of the individual sites, and distributed nature of the technology has made both interoperability across the sites and the search for resources within a site major research topics. This article will describe a system that addresses both issues using standard Web protocols and meta-data labels to implement an inventory of on-line resources across a group of sites. The success of this system is strongly dependent on the existence of and adherence to a standards architecture that guides the management of meta-data within participating sites.

  10. Energy Management of Smart Distribution Systems

    Science.gov (United States)

    Ansari, Bananeh

    Electric power distribution systems interface the end-users of electricity with the power grid. Traditional distribution systems are operated in a centralized fashion with the distribution system owner or operator being the only decision maker. The management and control architecture of distribution systems needs to gradually transform to accommodate the emerging smart grid technologies, distributed energy resources, and active electricity end-users or prosumers. The content of this document concerns with developing multi-task multi-objective energy management schemes for: 1) commercial/large residential prosumers, and 2) distribution system operator of a smart distribution system. The first part of this document describes a method of distributed energy management of multiple commercial/ large residential prosumers. These prosumers not only consume electricity, but also generate electricity using their roof-top solar photovoltaics systems. When photovoltaics generation is larger than local consumption, excess electricity will be fed into the distribution system, creating a voltage rise along the feeder. Distribution system operator cannot tolerate a significant voltage rise. ES can help the prosumers manage their electricity exchanges with the distribution system such that minimal voltage fluctuation occurs. The proposed distributed energy management scheme sizes and schedules each prosumer's ES to reduce the electricity bill and mitigate voltage rise along the feeder. The second part of this document focuses on emergency energy management and resilience assessment of a distribution system. The developed emergency energy management system uses available resources and redundancy to restore the distribution system's functionality fully or partially. The success of the restoration maneuver depends on how resilient the distribution system is. Engineering resilience terminology is used to evaluate the resilience of distribution system. The proposed emergency energy

  11. The Impact of Connecting Distributed Generation to the Distribution System

    Directory of Open Access Journals (Sweden)

    E. V. Mgaya

    2007-01-01

    Full Text Available This paper deals with the general problem of utilizing of renewable energy sources to generate electric energy. Recent advances in renewable energy power generation technologies, e.g., wind and photovoltaic (PV technologies, have led to increased interest in the application of these generation devices as distributed generation (DG units. This paper presents the results of an investigation into possible improvements in the system voltage profile and reduction of system losses when adding wind power DG (wind-DG to a distribution system. Simulation results are given for a case study, and these show that properly sized wind DGs, placed at carefully selected sites near key distribution substations, could be very effective in improving the distribution system voltage profile and reducing power losses, and hence could  improve the effective capacity of the system

  12. Control and operation of distributed generation in distribution systems

    DEFF Research Database (Denmark)

    Mahat, Pukar; Chen, Zhe; Bak-Jensen, Birgitte

    2011-01-01

    Many distribution systems nowadays have significant penetration of distributed generation (DG)and thus, islanding operation of these distribution systems is becoming a viable option for economical and technical reasons. The DG should operate optimally during both grid-connected and island...... algorithm, which uses average rate of change off requency (Af5) and real power shift RPS), in the islanded mode. RPS will increase or decrease the power set point of the generator with increasing or decreasing system frequency, respectively. Simulation results show that the proposed method can operate...

  13. Islanding Operation of Distribution System with Distributed Generations

    DEFF Research Database (Denmark)

    Mahat, Pukar; Chen, Zhe; Bak-Jensen, Birgitte

    2010-01-01

    The growing interest in distributed generations (DGs) due to environmental concern and various other reasons have resulted in significant penetration of DGs in many distribution system worldwide. DGs come with many benefits. One of the benefits is improved reliability by supplying load during power...

  14. Low jitter RF distribution system

    Science.gov (United States)

    Wilcox, Russell; Doolittle, Lawrence; Huang, Gang

    2012-09-18

    A timing signal distribution system includes an optical frequency stabilized laser signal amplitude modulated at an rf frequency. A transmitter box transmits a first portion of the laser signal and receive a modified optical signal, and outputs a second portion of the laser signal and a portion of the modified optical signal. A first optical fiber carries the first laser signal portion and the modified optical signal, and a second optical fiber carries the second portion of the laser signal and the returned modified optical signal. A receiver box receives the first laser signal portion, shifts the frequency of the first laser signal portion outputs the modified optical signal, and outputs an electrical signal on the basis of the laser signal. A detector at the end of the second optical fiber outputs a signal based on the modified optical signal. An optical delay sensing circuit outputs a data signal based on the detected modified optical signal. An rf phase detect and correct signal circuit outputs a signal corresponding to a phase stabilized rf signal based on the data signal and the frequency received from the receiver box.

  15. RELIABILITY ANALYSIS OF POWER DISTRIBUTION SYSTEMS

    Directory of Open Access Journals (Sweden)

    Popescu V.S.

    2012-04-01

    Full Text Available Power distribution systems are basic parts of power systems and reliability of these systems at present is a key issue for power engineering development and requires special attention. Operation of distribution systems is accompanied by a number of factors that produce random data a large number of unplanned interruptions. Research has shown that the predominant factors that have a significant influence on the reliability of distribution systems are: weather conditions (39.7%, defects in equipment(25% and unknown random factors (20.1%. In the article is studied the influence of random behavior and are presented estimations of reliability of predominantly rural electrical distribution systems.

  16. Review on Islanding Operation of Distribution System with Distributed Generation

    DEFF Research Database (Denmark)

    Mahat, Pukar; Chen, Zhe; Bak-Jensen, Birgitte

    2011-01-01

    The growing environmental concern and various benefits of distributed generation (DG) have resulted in significant penetration of DG in many distribution systems worldwide. One of the major expected benefits of DG is the improvement in the reliability of power supply by supplying load during power...... outage by operating in an island mode. However, there are many challenges to overcome before islanding operation of a distribution system with DG can become a viable solution in future. This paper reviews some of the major challenges with islanding operation and explores some possible solutions...

  17. Distributed radiation protection console system

    International Nuclear Information System (INIS)

    Chhokra, R.S.; Deshpande, V.K.; Mishra, H.; Rajeev, K.P.; Thakur, Bipla B.; Munj, Niket

    2004-01-01

    Radiation exposure control is one of the most important aspects in any nuclear facility . It encompasses continuous monitoring of the various areas of the facility to detect any increase in the radiation level and/or the air activity level beyond preset limits and alarm the O and M personnel working in these areas. Detection and measurement of radiation level and the air activity level is carried out by a number of monitors installed in the areas. These monitors include Area Gamma Monitors, Continuous Air Monitors, Pu-In-Air Monitors, Criticality Monitors etc. Traditionally, these measurements are displayed and recorded on a Central Radiation Protection Console(CRPC), which is located in the central control room of the facility. This methodology suffers from the shortcoming that any worker required to enter a work area will have to inquire about the radiation status of the area either from the CRPC or will get to know the same directly from the installed only after entering the area. This shortcoming can lead to avoidable delays in attending to the work or to unwanted exposure. The authors have designed and developed a system called Distributed Radiation Protection Console (DRPC) to overcome this shortcoming. A DRPC is a console which is located outside the entrance of a given area and displays the radiation status of the area. It presents to health physicist and the plant operators a graphic over-view of the radiation and air activity levels in the particular area of the plant. It also provides audio visual annunciation of the alarm status. Each radioactive area in a nuclear facility will have its own DRPC, which will receive as its inputs the analog and digital signals from radiation monitoring instruments installed in the area and would not only show those readings on its video graphic screen but will also provide warning messages and instructions to the personnel entering the active areas. The various DRPCs can be integrated into a Local Area Network, where the

  18. Control and Operation of Islanded Distribution System

    DEFF Research Database (Denmark)

    Mahat, Pukar

    deviation and real power shift. When a distribution system, with all its generators operating at maximum power, is islanded, the frequency will go down if the total load is more than the total generation. An under-frequency load shedding procedure for islanded distribution systems with DG unit(s) based...... states. Short circuit power also changes when some of the generators in the distribution system are disconnected. This may result in elongation of fault clearing time and hence disconnection of equipments (including generators) in the distribution system or unnecessary operation of protective devices...... operational challenges. But, on the other hand, it has also opened up some opportunities. One opportunity/challenge is an islanded operation of a distribution system with DG unit(s). Islanding is a situation in which a distribution system becomes electrically isolated from the remainder of the power system...

  19. DIAMONDS: Engineering Distributed Object Systems

    National Research Council Canada - National Science Library

    Cheng, Evan

    1997-01-01

    This report describes DIAMONDS, a research project at Syracuse University, that is dedicated to producing both a methodology and corresponding tools to assist in the development of heterogeneous distributed software...

  20. Water sample-collection and distribution system

    Science.gov (United States)

    Brooks, R. R.

    1978-01-01

    Collection and distribution system samples water from six designated stations, filtered if desired, and delivers it to various analytical sensors. System may be controlled by Water Monitoring Data Acquisition System or operated manually.

  1. The ATLAS distributed analysis system

    OpenAIRE

    Legger, F.

    2014-01-01

    In the LHC operations era, analysis of the multi-petabyte ATLAS data sample by globally distributed physicists is a challenging task. To attain the required scale the ATLAS Computing Model was designed around the concept of grid computing, realized in the Worldwide LHC Computing Grid (WLCG), the largest distributed computational resource existing in the sciences. The ATLAS experiment currently stores over 140 PB of data and runs about 140,000 concurrent jobs continuously at WLCG sites. During...

  2. 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.

  3. On Distributed Port-Hamiltonian Process Systems

    NARCIS (Netherlands)

    Lopezlena, Ricardo; Scherpen, Jacquelien M.A.

    2004-01-01

    In this paper we use the term distributed port-Hamiltonian Process Systems (DPHPS) to refer to the result of merging the theory of distributed Port-Hamiltonian systems (DPHS) with the theory of process systems (PS). Such concept is useful for combining the systematic interconnection of PHS with the

  4. Distributed Cognition and Distributed Morality: Agency, Artifacts and Systems.

    Science.gov (United States)

    Heersmink, Richard

    2017-04-01

    There are various philosophical approaches and theories describing the intimate relation people have to artifacts. In this paper, I explore the relation between two such theories, namely distributed cognition and distributed morality theory. I point out a number of similarities and differences in these views regarding the ontological status they attribute to artifacts and the larger systems they are part of. Having evaluated and compared these views, I continue by focussing on the way cognitive artifacts are used in moral practice. I specifically conceptualise how such artifacts (a) scaffold and extend moral reasoning and decision-making processes, (b) have a certain moral status which is contingent on their cognitive status, and (c) whether responsibility can be attributed to distributed systems. This paper is primarily written for those interested in the intersection of cognitive and moral theory as it relates to artifacts, but also for those independently interested in philosophical debates in extended and distributed cognition and ethics of (cognitive) technology.

  5. Applying Distributed Object Technology to Distributed Embedded Control Systems

    DEFF Research Database (Denmark)

    Jørgensen, Bo Nørregaard; Dalgaard, Lars

    2012-01-01

    In this paper, we describe our Java RMI inspired Object Request Broker architecture MicroRMI for use with networked embedded devices. MicroRMI relieves the software developer from the tedious and error-prone job of writing communication protocols for interacting with such embedded devices. MicroR...... in developing control systems for distributed embedded platforms possessing severe resource restrictions.......RMI supports easy integration of high-level application specific control logic with low-level device specific control logic. Our experience from applying MicroRMI in the context of a distributed robotics control application, clearly demonstrates that it is feasible to use distributed object technology...

  6. Thermal Distribution System | Energy Systems Integration Facility | NREL

    Science.gov (United States)

    Thermal Distribution System Thermal Distribution System The Energy Systems Integration Facility's . Photo of the roof of the Energy Systems Integration Facility. The thermal distribution bus allows low as 10% of its full load level). The 60-ton chiller cools water with continuous thermal control

  7. Distributed systems for protecting nuclear power stations

    International Nuclear Information System (INIS)

    Jover, P.

    1980-05-01

    The advantages of distributed control systems for the control of nuclear power stations are obviously of great interest. Some years ago, EPRI, (Electric Power Research Institute) showed that multiplexing the signals is technically feasible, that it enables the availability specifications to be met and costs to be reduced. Since then, many distributed control systems have been proposed by the manufacturers. This note offers some comments on the application of the distribution concept to protection systems -what should be distributed- and ends with a brief description of a protection system based on microprocessors for the pressurized power stations now being built in France [fr

  8. Distributed computer systems theory and practice

    CERN Document Server

    Zedan, H S M

    2014-01-01

    Distributed Computer Systems: Theory and Practice is a collection of papers dealing with the design and implementation of operating systems, including distributed systems, such as the amoeba system, argus, Andrew, and grapevine. One paper discusses the concepts and notations for concurrent programming, particularly language notation used in computer programming, synchronization methods, and also compares three classes of languages. Another paper explains load balancing or load redistribution to improve system performance, namely, static balancing and adaptive load balancing. For program effici

  9. Online Scheduling in Distributed Message Converter Systems

    NARCIS (Netherlands)

    Risse, Thomas; Wombacher, Andreas; Surridge, Mike; Taylor, Steve; Aberer, Karl

    The optimal distribution of jobs among hosts in distributed environments is an important factor to achieve high performance. The optimal strategy depends on the application. In this paper we present a new online scheduling strategy for distributed EDI converter system. The strategy is based on the

  10. Protection of Distribution Systems with Distributed Energy Resources

    DEFF Research Database (Denmark)

    Bak-Jensen, Birgitte; Browne, Matthew; Calone, Roberto

    of 17 months of work of the Joint Working Group B5/C6.26/CIRED “Protection of Distribution Systems with Distributed Energy Resources”. The working group used the CIGRE report TB421 “The impact of Renewable Energy Sources and Distributed Generation on Substation Protection and Automation”, published...... by WG B5.34 as the entry document for the work on this report. In doing so, the group aligned the content and the scope of this report, the network structures considered, possible islanding, standardized communication and adaptive protection, interface protection, connection schemes and protection...... are listed (chapter 3). The first main part of the report starts with a summary of the backgrounds on DER and current practices in protection at the distribution level (chapter 4). This chapter contains an analysis of CIGRE TB421, protection relevant characteristics of DER, a review of current practices...

  11. Strategy Guideline. Compact Air Distribution Systems

    Energy Technology Data Exchange (ETDEWEB)

    Burdick, Arlan [IBACOS, Inc., Pittsburgh, PA (United States)

    2013-06-01

    This guideline discusses the benefits and challenges of using a compact air distribution system to handle the reduced loads and reduced air volume needed to condition the space within an energy efficient home. The decision criteria for a compact air distribution system must be determined early in the whole-house design process, considering both supply and return air design. However, careful installation of a compact air distribution system can result in lower material costs from smaller equipment, shorter duct runs, and fewer outlets; increased installation efficiencies, including ease of fitting the system into conditioned space; lower loads on a better balanced HVAC system, and overall improved energy efficiency of the home.

  12. Internet and redefining tourism distribution system

    Directory of Open Access Journals (Sweden)

    Đelić Tanja

    2004-01-01

    Full Text Available Since the introduction, computerized systems that manage reservation systems, rapidly became inevitable distribution channel for all service companies in tourist industry. GDS in reality using communication network connects service offer, selling personnel and air companies.

  13. DC Distribution Systems and Microgrids

    DEFF Research Database (Denmark)

    Dragicevic, Tomislav; Anvari-Moghaddam, Amjad; Quintero, Juan Carlos Vasquez

    2017-01-01

    summarized. Due to its attractive characteristics in terms of compliance with modern generation, storage and electronic load technologies, high reliability and current carrying capacity, as well as simple control, DC systems are already an indispensable part of power systems. Moreover, the existing......A qualitative overview of different hardware topologies and control systems for DC MGs has been presented in this chapter. Some challenges and design considerations of DC protections systems have also been discussed. Finally, applications of DC MGs in emerging smart grid applications have been...... challenges such as protection issues will be effectively resolved in the near future due to fast progress of semiconductor technology which is a key enabler cheap and reliable future DC solid-state protection systems. Therefore, it is the view of the author that more and more DC systems will appear...

  14. Economic Models and Algorithms for Distributed Systems

    CERN Document Server

    Neumann, Dirk; Altmann, Jorn; Rana, Omer F

    2009-01-01

    Distributed computing models for sharing resources such as Grids, Peer-to-Peer systems, or voluntary computing are becoming increasingly popular. This book intends to discover fresh avenues of research and amendments to existing technologies, aiming at the successful deployment of commercial distributed systems

  15. Hybrid solar lighting distribution systems and components

    Science.gov (United States)

    Muhs, Jeffrey D [Lenoir City, TN; Earl, Dennis D [Knoxville, TN; Beshears, David L [Knoxville, TN; Maxey, Lonnie C [Powell, TN; Jordan, John K [Oak Ridge, TN; Lind, Randall F [Lenoir City, TN

    2011-07-05

    A hybrid solar lighting distribution system and components having at least one hybrid solar concentrator, at least one fiber receiver, at least one hybrid luminaire, and a light distribution system operably connected to each hybrid solar concentrator and each hybrid luminaire. A controller operates all components.

  16. Formal Specification of Distributed Information Systems

    NARCIS (Netherlands)

    Vis, J.; Brinksma, Hendrik; de By, R.A.; de By, R.A.

    The design of distributed information systems tends to be complex and therefore error-prone. However, in the field of monolithic, i.e. non-distributed, information systems much has already been achieved, and by now, the principles of their design seem to be fairly well-understood. The past decade

  17. RF phase distribution systems at the SLC

    International Nuclear Information System (INIS)

    Jobe, R.K.; Schwarz, H.D.

    1989-04-01

    Modern large linear accelerators require RF distribution systems with minimal phase drifts and errors. Through the use of existing RF coaxial waveguides, and additional installation of phase reference cables and monitoring equipment, stable RF distribution for the SLC has been achieved. This paper discusses the design and performance of SLAC systems, and some design considerations for future colliders. 6 refs., 4 figs

  18. Silver disinfection in water distribution systems

    Science.gov (United States)

    Silvestry Rodriguez, Nadia

    Silver was evaluated as disinfectant to maintain water quality in water distribution system. It was used to inhibit growth of two opportunistic bacteria in planktonik form and in biofilm formation in Robbins devices with stainless steel and PVC surfaces. The results of this work show that silver is a potential secondary disinfectant to be used in water distribution systems.

  19. Rapid Prototyping of Formally Modelled Distributed Systems

    OpenAIRE

    Buchs, Didier; Buffo, Mathieu; Titsworth, Frances M.

    1999-01-01

    This paper presents various kinds of prototypes, used in the prototyping of formally modelled distributed systems. It presents the notions of prototyping techniques and prototype evolution, and shows how to relate them to the software life-cycle. It is illustrated through the use of the formal modelling language for distributed systems CO-OPN/2.

  20. Programming a Distributed System Using Shared Objects

    NARCIS (Netherlands)

    Tanenbaum, A.S.; Bal, H.E.; Kaashoek, M.F.

    1993-01-01

    Building the hardware for a high-performance distributed computer system is a lot easier than building its software. The authors describe a model for programming distributed systems based on abstract data types that can be replicated on all machines that need them. Read operations are done locally,

  1. BIOFILMS IN DRINKING WATER DISTRIBUTION SYSTEMS

    Science.gov (United States)

    Virtually anywhere a surface comes into contact with the water in a distribution system, one can find biofilms. Biofilms are formed in distribution system pipelines when microbial cells attach to pipe surfaces and multiply to form a film or slime layer on the pipe. Probably withi...

  2. Grid-connected distributed solar power systems

    Science.gov (United States)

    Moyle, R.; Chernoff, H.; Schweizer, T.

    This paper discusses some important, though often ignored, technical and economic issues of distributed solar power systems: protection of the utility system and nonsolar customers requires suitable interfaced equipment. Purchase criteria must mirror reality; most analyses use life-cycle costing with low discount rates - most buyers use short payback periods. Distributing, installing, and marketing small, distributed solar systems is more costly than most analyses estimate. Results show that certain local conditions and uncommon purchase considerations can combine to make small, distributed solar power attractive, but lower interconnect costs (per kW), lower marketing and product distribution costs, and more favorable purchase criteria make large, centralized solar energy more attractive. Specifically, the value of dispersed solar systems to investors and utilities can be higher than $2000/kw. However, typical residential owners place a value of well under $1000 on the installed system.

  3. Reliability assessment of distribution power systems including distributed generations

    International Nuclear Information System (INIS)

    Megdiche, M.

    2004-12-01

    Nowadays, power systems have reached a good level of reliability. Nevertheless, considering the modifications induced by the connections of small independent producers to distribution networks, there's a need to assess the reliability of these new systems. Distribution networks present several functional characteristics, highlighted by the qualitative study of the failures, as dispersed loads at several places, variable topology and some electrotechnical phenomena which must be taken into account to model the events that can occur. The adopted reliability calculations method is Monte Carlo simulations, the probabilistic method most powerful and most flexible to model complex operating of the distribution system. We devoted a first part on the case of a 20 kV feeder to which a cogeneration unit is connected. The method was applied to a software of stochastic Petri nets simulations. Then a second part related to the study of a low voltage power system supplied by dispersed generations. Here, the complexity of the events required to code the method in an environment of programming allowing the use of power system calculations (load flow, short-circuit, load shedding, management of units powers) in order to analyse the system state for each new event. (author)

  4. Large scale network-centric distributed systems

    CERN Document Server

    Sarbazi-Azad, Hamid

    2014-01-01

    A highly accessible reference offering a broad range of topics and insights on large scale network-centric distributed systems Evolving from the fields of high-performance computing and networking, large scale network-centric distributed systems continues to grow as one of the most important topics in computing and communication and many interdisciplinary areas. Dealing with both wired and wireless networks, this book focuses on the design and performance issues of such systems. Large Scale Network-Centric Distributed Systems provides in-depth coverage ranging from ground-level hardware issu

  5. Differences Between Distributed and Parallel Systems

    Energy Technology Data Exchange (ETDEWEB)

    Brightwell, R.; Maccabe, A.B.; Rissen, R.

    1998-10-01

    Distributed systems have been studied for twenty years and are now coming into wider use as fast networks and powerful workstations become more readily available. In many respects a massively parallel computer resembles a network of workstations and it is tempting to port a distributed operating system to such a machine. However, there are significant differences between these two environments and a parallel operating system is needed to get the best performance out of a massively parallel system. This report characterizes the differences between distributed systems, networks of workstations, and massively parallel systems and analyzes the impact of these differences on operating system design. In the second part of the report, we introduce Puma, an operating system specifically developed for massively parallel systems. We describe Puma portals, the basic building blocks for message passing paradigms implemented on top of Puma, and show how the differences observed in the first part of the report have influenced the design and implementation of Puma.

  6. Asymptotic work distributions in driven bistable systems

    International Nuclear Information System (INIS)

    Nickelsen, D; Engel, A

    2012-01-01

    The asymptotic tails of the probability distributions of thermodynamic quantities convey important information about the physics of nanoscopic systems driven out of equilibrium. We apply a recently proposed method to analytically determine the asymptotics of work distributions in Langevin systems to an one-dimensional model of single-molecule force spectroscopy. The results are in excellent agreement with numerical simulations, even in the centre of the distributions. We compare our findings with a recent proposal for an universal form of the asymptotics of work distributions in single-molecule experiments.

  7. Centralised and distributed electricity systems

    International Nuclear Information System (INIS)

    Bouffard, Francois; Kirschen, Daniel S.

    2008-01-01

    Because of their high level of integration, centralised energy supply systems are vulnerable to disturbances in the supply chain. In the case of electricity especially, this supply paradigm is losing some of its appeal. Apart from vulnerability, a number of further aggravating factors are reducing its attractiveness. They include the depletion of fossil fuels and their climate change impact, the insecurities affecting energy transportation infrastructure, and the desire of investors to minimise risks through the deployment of smaller-scale, modular generation and transmission systems. Small-scale decentralised systems, where energy production and consumption are usually tightly coupled, are emerging as a viable alternative. They are less dependent upon centralised energy supply, and can sometimes use more than one energy source. They are less sensitive to the uncertain availability of remote primary energy and transportation networks. In addition, the close connection between energy generation and use makes decentralised systems cleaner because they are most often based on renewable energies or on high-efficiency fossil fuel-based technologies such as combined heat and power (CHP). Fully decentralised energy supply is not currently possible or even truly desirable. The secure and clean energy systems of the future will be those flexible enough to allow for a spectrum of hybrid modes of operation and investment, combining the best attributes of both paradigms. A large part of this flexibility will come from the networks that make it possible to combine these two types of infrastructures and obtain the benefits of both approaches

  8. Light distribution system comprising spectral conversion means

    DEFF Research Database (Denmark)

    2012-01-01

    , longer wavelength,a spectral conversion characteristics of the spectral conversion fibre being essentially determined by the spectral absorption and emission properties of the photoluminescent agent, the amount of photo- luminescent agent,and the distribution of the photoluminescent agent in the spectral......System (200, 300) for the distribution of white light, having a supply side (201, 301, 401) and a delivery side (202, 302, 402), the system being configured for guiding light with a multitude of visible wavelengths in a propagation direction P from the supply side to the distribution side...... of providing a light distribution system and a method of correcting the spectral transmission characteristics of a light distribution system are disclosed....

  9. Evaluation of two typical distributed energy systems

    Science.gov (United States)

    Han, Miaomiao; Tan, Xiu

    2018-03-01

    According to the two-natural gas distributed energy system driven by gas engine driven and gas turbine, in this paper, the first and second laws of thermodynamics are used to measure the distributed energy system from the two parties of “quantity” and “quality”. The calculation results show that the internal combustion engine driven distributed energy station has a higher energy efficiency, but the energy efficiency is low; the gas turbine driven distributed energy station energy efficiency is high, but the primary energy utilization rate is relatively low. When configuring the system, we should determine the applicable natural gas distributed energy system technology plan and unit configuration plan according to the actual load factors of the project and the actual factors such as the location, background and environmental requirements of the project. “quality” measure, the utilization of waste heat energy efficiency index is proposed.

  10. PFS: a distributed and customizable file system

    NARCIS (Netherlands)

    Bosch, H.G.P.; Mullender, Sape J.

    1996-01-01

    In this paper we present our ongoing work on the Pegasus File System (PFS), a distributed and customizable file system that can be used for off-line file system experiments and on-line file system storage. PFS is best described as an object-oriented component library from which either a true file

  11. 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...

  12. Support system for ATLAS distributed computing operations

    CERN Document Server

    Kishimoto, Tomoe; The ATLAS collaboration

    2018-01-01

    The ATLAS distributed computing system has allowed the experiment to successfully meet the challenges of LHC Run 2. In order for distributed computing to operate smoothly and efficiently, several support teams are organized in the ATLAS experiment. The ADCoS (ATLAS Distributed Computing Operation Shifts) is a dedicated group of shifters who follow and report failing jobs, failing data transfers between sites, degradation of ATLAS central computing services, and more. The DAST (Distributed Analysis Support Team) provides user support to resolve issues related to running distributed analysis on the grid. The CRC (Computing Run Coordinator) maintains a global view of the day-to-day operations. In this presentation, the status and operational experience of the support system for ATLAS distributed computing in LHC Run 2 will be reported. This report also includes operations experience from the grid site point of view, and an analysis of the errors that create the biggest waste of wallclock time. The report of oper...

  13. A DISTRIBUTED SMART HOME ARTIFICIAL INTELLIGENCE SYSTEM

    DEFF Research Database (Denmark)

    Lynggaard, Per

    2013-01-01

    A majority of the research performed today explore artificial intelligence in smart homes by using a centralized approach where a smart home server performs the necessary calculations. This approach has some disadvantages that can be overcome by shifting focus to a distributed approach where...... the artificial intelligence system is implemented as distributed as agents running parts of the artificial intelligence system. This paper presents a distributed smart home architecture that distributes artificial intelligence in smart homes and discusses the pros and cons of such a concept. The presented...... distributed model is a layered model. Each layer offers a different complexity level of the embedded distributed artificial intelligence. At the lowest layer smart objects exists, they are small cheap embedded microcontroller based smart devices that are powered by batteries. The next layer contains a more...

  14. Parallel and Distributed System Simulation

    Science.gov (United States)

    Dongarra, Jack

    1998-01-01

    This exploratory study initiated our research into the software infrastructure necessary to support the modeling and simulation techniques that are most appropriate for the Information Power Grid. Such computational power grids will use high-performance networking to connect hardware, software, instruments, databases, and people into a seamless web that supports a new generation of computation-rich problem solving environments for scientists and engineers. In this context we looked at evaluating the NetSolve software environment for network computing that leverages the potential of such systems while addressing their complexities. NetSolve's main purpose is to enable the creation of complex applications that harness the immense power of the grid, yet are simple to use and easy to deploy. NetSolve uses a modular, client-agent-server architecture to create a system that is very easy to use. Moreover, it is designed to be highly composable in that it readily permits new resources to be added by anyone willing to do so. In these respects NetSolve is to the Grid what the World Wide Web is to the Internet. But like the Web, the design that makes these wonderful features possible can also impose significant limitations on the performance and robustness of a NetSolve system. This project explored the design innovations that push the performance and robustness of the NetSolve paradigm as far as possible without sacrificing the Web-like ease of use and composability that make it so powerful.

  15. Integrating photovoltaics into utility distribution systems

    International Nuclear Information System (INIS)

    Zaininger, H.W.; Barnes, P.R.

    1995-01-01

    Electric utility distribution system impacts associated with the integration of distributed photovoltaic (PV) energy sources vary from site to site and utility to utility. The objective of this paper is to examine several utility- and site-specific conditions which may affect economic viability of distributed PV applications to utility systems. Assessment methodology compatible with technical and economic assessment techniques employed by utility engineers and planners is employed to determine PV benefits for seven different utility systems. The seven case studies are performed using utility system characteristics and assumptions obtained from appropriate utility personnel. The resulting site-specific distributed PV benefits increase nonsite-specific generation system benefits available to central station PV plants as much as 46%, for one utility located in the Southwest

  16. Equilibrium distribution function in collisionless systems

    International Nuclear Information System (INIS)

    Pergamenshchik, V.M.

    1988-01-01

    Collisionless systems of a large number of N particles interacting by Coulomb forces are widely spread in cosmic and laboratory plasma. A statistical theory of equilibrium state of collisionless Coulomb systems which evolution obeys Vlasov equation is proposed. The developed formalism permits a sequential consideration of such distributed in one-particle six-dimensional phase space of a system and to obtain a simple result: equilibrium distribution function has the form of Fermi-Dirac distribution and doesn't depend on initial state factors

  17. Advanced smartgrids for distribution system operators

    CERN Document Server

    Boillot, Marc

    2014-01-01

    The dynamic of the Energy Transition is engaged in many region of the World. This is a real challenge for electric systems and a paradigm shift for existing distribution networks. With the help of "advanced" smart technologies, the Distribution System Operators will have a central role to integrate massively renewable generation, electric vehicle and demand response programs. Many projects are on-going to develop and assess advanced smart grids solutions, with already some lessons learnt. In the end, the Smart Grid is a mean for Distribution System Operators to ensure the quality and the secu

  18. Data Distribution Service for Industrial Automation

    OpenAIRE

    Yang, Jinsong

    2012-01-01

    In industrial automation systems, there is usually large volume of data which needs to be delivered to right places at the right time. In addition, large number of nodes in the automation systems are usually distributed which increases the complexity that there needs to be more point-to-point Ethernet-connections in the network. Hence, it is necessary to apply data-centric design and reduce the connection complexity. Data Distributed Service for Real-Time Systems (DDS) is a data-centric middl...

  19. Science network resources: Distributed systems

    Science.gov (United States)

    Cline, Neal

    1991-01-01

    The Master Directory, which is overview information about whole data sets, is outlined. The data system environment is depicted. The question is explored of what is a prototype international directory including purpose and features. Advantages of on-line directories are listed. Interconnected directory assumptions are given. A description of given of DIF (Directory Interchange Format), which is an exchange file for directory information, along with information content of DIF and directories. The directory population status is given in a percentage viewgraph. The present and future directory interconnections status at GSFC is also listed.

  20. PROWAY - a standard for distributed control systems

    International Nuclear Information System (INIS)

    Gellie, R.W.

    1980-01-01

    The availability of cheap and powerful microcomputer and data communications equipment has led to a major revision of instrumentation and control systems. Intelligent devices can now be used and distributed about the control system in a systematic and economic manner. These sub-units are linked by a communications system to provide a total system capable of meeting the required plant objectives. PROWAY, an international standard process data highway for interconnecting processing units in distributed industrial process control systems, is currently being developed. This paper describes the salient features and current status of the PROWAY effort. (auth)

  1. Water distribution systems design optimisation using metaheuristics ...

    African Journals Online (AJOL)

    The topic of multi-objective water distribution systems (WDS) design optimisation using metaheuristics is investigated, comparing numerous modern metaheuristics, including several multi-objective evolutionary algorithms, an estimation of distribution algorithm and a recent hyperheuristic named AMALGAM (an evolutionary ...

  2. Programming Languages for Distributed Computing Systems

    NARCIS (Netherlands)

    Bal, H.E.; Steiner, J.G.; Tanenbaum, A.S.

    1989-01-01

    When distributed systems first appeared, they were programmed in traditional sequential languages, usually with the addition of a few library procedures for sending and receiving messages. As distributed applications became more commonplace and more sophisticated, this ad hoc approach became less

  3. Distributed Administrative Management Information System (DAMIS).

    Science.gov (United States)

    Juckiewicz, Robert; Kroculick, Joseph

    Columbia University's major program to distribute its central administrative data processing to its various schools and departments is described. The Distributed Administrative Management Information System (DAMIS) will link every department and school within the university via micrcomputers, terminals, and/or minicomputers to the central…

  4. DIstributed VIRtual System (DIVIRS) Project

    Science.gov (United States)

    Schorr, Herbert; Neuman, B. Clifford; Gaines, Stockton R.; Mizell, David

    1996-01-01

    The development of Prospero moved from the University of Washington to ISI and several new versions of the software were released from ISI during the contract period. Changes in the first release from ISI included bug fixes and extensions to support the needs of specific users. Among these changes was a new option to directory queries that allows attributes to be returned for all files in a directory together with the directory listing. This change greatly improves the performance of their server and reduces the number of packets sent across their trans-pacific connection to the rest of the internet. Several new access method were added to the Prospero file method. The Prospero Data Access Protocol was designed, to support secure retrieval of data from systems running Prospero.

  5. AC distribution system for TFTR pulsed loads

    International Nuclear Information System (INIS)

    Carroll, R.F.; Ramakrishnan, S.; Lemmon, G.N.; Moo, W.I.

    1977-01-01

    This paper outlines the AC distribution system associated with the Tokamak Fusion Test Reactor and discusses the significant areas related to design, protection, and equipment selection, particularly where there is a departure from normal utility and industrial applications

  6. A distributed computer system for digitising machines

    International Nuclear Information System (INIS)

    Bairstow, R.; Barlow, J.; Waters, M.; Watson, J.

    1977-07-01

    This paper describes a Distributed Computing System, based on micro computers, for the monitoring and control of digitising tables used by the Rutherford Laboratory Bubble Chamber Research Group in the measurement of bubble chamber photographs. (author)

  7. Man-systems distributed system for Space Station Freedom

    Science.gov (United States)

    Lewis, J. L.

    1990-01-01

    Viewgraphs on man-systems distributed system for Space Station Freedom are presented. Topics addressed include: description of man-systems (definition, requirements, scope, subsystems, and topologies); implementation (approach, tools); man-systems interfaces (system to element and system to system); prime/supporting development relationship; selected accomplishments; and technical challenges.

  8. Supervisory Control and Diagnostics System Distributed Operating System

    International Nuclear Information System (INIS)

    McGoldrick, P.R.

    1979-01-01

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

  9. Distributed context-aware systems

    CERN Document Server

    Ferreira, Paulo

    2014-01-01

    Context-aware systems aim to deliver a rich user experience by taking into?account the current user context (location, time, activity, etc.), possibly?captured without his intervention. For example, cell phones are now able to?continuously update a user's location while, at the same time, users execute?an increasing amount of activities online, where their actions may be easily?captured (e.g. login in a web application) without user consent. In the last decade, this topic has seen numerous developments that demonstrate its relevance and usefulness. The?trend was accelerated with the widespread?availability of powerful mobile devices (e.g. smartphones) that include a myriad of?sensors which enable applications to capture the user context. However, there are several challenges that must be addressed; we focus on scalability?(large number of context aware messages) and privacy (personal data that may be propagated).?This book is organized in five chapters starting with an introduction to?the theme raising the mo...

  10. Distributed operating system for NASA ground stations

    Science.gov (United States)

    Doyle, John F.

    1987-01-01

    NASA ground stations are characterized by ever changing support requirements, so application software is developed and modified on a continuing basis. A distributed operating system was designed to optimize the generation and maintenance of those applications. Unusual features include automatic program generation from detailed design graphs, on-line software modification in the testing phase, and the incorporation of a relational database within a real-time, distributed system.

  11. Strategy Guideline: Compact Air Distribution Systems

    Energy Technology Data Exchange (ETDEWEB)

    Burdick, A.

    2013-06-01

    This Strategy Guideline discusses the benefits and challenges of using a compact air distribution system to handle the reduced loads and reduced air volume needed to condition the space within an energy efficient home. Traditional systems sized by 'rule of thumb' (i.e., 1 ton of cooling per 400 ft2 of floor space) that 'wash' the exterior walls with conditioned air from floor registers cannot provide appropriate air mixing and moisture removal in low-load homes. A compact air distribution system locates the HVAC equipment centrally with shorter ducts run to interior walls, and ceiling supply outlets throw the air toward the exterior walls along the ceiling plane; alternatively, high sidewall supply outlets throw the air toward the exterior walls. Potential drawbacks include resistance from installing contractors or code officials who are unfamiliar with compact air distribution systems, as well as a lack of availability of low-cost high sidewall or ceiling supply outlets to meet the low air volumes with good throw characteristics. The decision criteria for a compact air distribution system must be determined early in the whole-house design process, considering both supply and return air design. However, careful installation of a compact air distribution system can result in lower material costs from smaller equipment, shorter duct runs, and fewer outlets; increased installation efficiencies, including ease of fitting the system into conditioned space; lower loads on a better balanced HVAC system, and overall improved energy efficiency of the home.

  12. Distributed redundancy and robustness in complex systems

    KAUST Repository

    Randles, Martin

    2011-03-01

    The uptake and increasing prevalence of Web 2.0 applications, promoting new large-scale and complex systems such as Cloud computing and the emerging Internet of Services/Things, requires tools and techniques to analyse and model methods to ensure the robustness of these new systems. This paper reports on assessing and improving complex system resilience using distributed redundancy, termed degeneracy in biological systems, to endow large-scale complicated computer systems with the same robustness that emerges in complex biological and natural systems. However, in order to promote an evolutionary approach, through emergent self-organisation, it is necessary to specify the systems in an \\'open-ended\\' manner where not all states of the system are prescribed at design-time. In particular an observer system is used to select robust topologies, within system components, based on a measurement of the first non-zero Eigen value in the Laplacian spectrum of the components\\' network graphs; also known as the algebraic connectivity. It is shown, through experimentation on a simulation, that increasing the average algebraic connectivity across the components, in a network, leads to an increase in the variety of individual components termed distributed redundancy; the capacity for structurally distinct components to perform an identical function in a particular context. The results are applied to a specific application where active clustering of like services is used to aid load balancing in a highly distributed network. Using the described procedure is shown to improve performance and distribute redundancy. © 2010 Elsevier Inc.

  13. Support for User Interfaces for Distributed Systems

    Science.gov (United States)

    Eychaner, Glenn; Niessner, Albert

    2005-01-01

    An extensible Java(TradeMark) software framework supports the construction and operation of graphical user interfaces (GUIs) for distributed computing systems typified by ground control systems that send commands to, and receive telemetric data from, spacecraft. Heretofore, such GUIs have been custom built for each new system at considerable expense. In contrast, the present framework affords generic capabilities that can be shared by different distributed systems. Dynamic class loading, reflection, and other run-time capabilities of the Java language and JavaBeans component architecture enable the creation of a GUI for each new distributed computing system with a minimum of custom effort. By use of this framework, GUI components in control panels and menus can send commands to a particular distributed system with a minimum of system-specific code. The framework receives, decodes, processes, and displays telemetry data; custom telemetry data handling can be added for a particular system. The framework supports saving and later restoration of users configurations of control panels and telemetry displays with a minimum of effort in writing system-specific code. GUIs constructed within this framework can be deployed in any operating system with a Java run-time environment, without recompilation or code changes.

  14. Comparison between Different Air Distribution Systems

    DEFF Research Database (Denmark)

    Nielsen, Peter V.

    The aim of an air conditioning system is to remove excess heat in a room and replace room air with fresh air to obtain a high air quality. It is not sufficient to remove heat and contaminated air, it is also necessary to distribute and control the air movement in the room to create thermal comfort...... in the occupied zone. Most air distribution systems are based on mixing ventilation with ceiling or wall-mounted diffusers or on displacement ventilation with wall-mounted low velocity diffusers. New principles for room air distribution were introduced during the last decades, as the textile terminals mounted...... in the ceiling and radial diffusers with swirling flow also mounted in the ceiling. This paper addresses five air distribution systems in all, namely mixing ventilation from a wallmounted terminal, mixing ventilation from a ceiling-mounted diffuser, mixing ventilation from a ceiling-mounted diffuser...

  15. Bluetooth-based distributed measurement system

    International Nuclear Information System (INIS)

    Tang Baoping; Chen Zhuo; Wei Yuguo; Qin Xiaofeng

    2007-01-01

    A novel distributed wireless measurement system, which is consisted of a base station, wireless intelligent sensors and relay nodes etc, is established by combining of Bluetooth-based wireless transmission, virtual instrument, intelligent sensor, and network. The intelligent sensors mounted on the equipments to be measured acquire various parameters and the Bluetooth relay nodes get the acquired data modulated and sent to the base station, where data analysis and processing are done so that the operational condition of the equipment can be evaluated. The establishment of the distributed measurement system is discussed with a measurement flow chart for the distributed measurement system based on Bluetooth technology, and the advantages and disadvantages of the system are analyzed at the end of the paper and the measurement system has successfully been used in Daqing oilfield, China for measurement of parameters, such as temperature, flow rate and oil pressure at an electromotor-pump unit

  16. Bluetooth-based distributed measurement system

    Science.gov (United States)

    Tang, Baoping; Chen, Zhuo; Wei, Yuguo; Qin, Xiaofeng

    2007-07-01

    A novel distributed wireless measurement system, which is consisted of a base station, wireless intelligent sensors and relay nodes etc, is established by combining of Bluetooth-based wireless transmission, virtual instrument, intelligent sensor, and network. The intelligent sensors mounted on the equipments to be measured acquire various parameters and the Bluetooth relay nodes get the acquired data modulated and sent to the base station, where data analysis and processing are done so that the operational condition of the equipment can be evaluated. The establishment of the distributed measurement system is discussed with a measurement flow chart for the distributed measurement system based on Bluetooth technology, and the advantages and disadvantages of the system are analyzed at the end of the paper and the measurement system has successfully been used in Daqing oilfield, China for measurement of parameters, such as temperature, flow rate and oil pressure at an electromotor-pump unit.

  17. Bluetooth-based distributed measurement system

    Energy Technology Data Exchange (ETDEWEB)

    Tang Baoping; Chen Zhuo; Wei Yuguo; Qin Xiaofeng [Department of Mechatronics, College of Mechanical Engineering, Chongqing University, Chongqing, 400030 (China)

    2007-07-15

    A novel distributed wireless measurement system, which is consisted of a base station, wireless intelligent sensors and relay nodes etc, is established by combining of Bluetooth-based wireless transmission, virtual instrument, intelligent sensor, and network. The intelligent sensors mounted on the equipments to be measured acquire various parameters and the Bluetooth relay nodes get the acquired data modulated and sent to the base station, where data analysis and processing are done so that the operational condition of the equipment can be evaluated. The establishment of the distributed measurement system is discussed with a measurement flow chart for the distributed measurement system based on Bluetooth technology, and the advantages and disadvantages of the system are analyzed at the end of the paper and the measurement system has successfully been used in Daqing oilfield, China for measurement of parameters, such as temperature, flow rate and oil pressure at an electromotor-pump unit.

  18. Integrating CLIPS applications into heterogeneous distributed systems

    Science.gov (United States)

    Adler, Richard M.

    1991-01-01

    SOCIAL is an advanced, object-oriented development tool for integrating intelligent and conventional applications across heterogeneous hardware and software platforms. SOCIAL defines a family of 'wrapper' objects called agents, which incorporate predefined capabilities for distributed communication and control. Developers embed applications within agents and establish interactions between distributed agents via non-intrusive message-based interfaces. This paper describes a predefined SOCIAL agent that is specialized for integrating C Language Integrated Production System (CLIPS)-based applications. The agent's high-level Application Programming Interface supports bidirectional flow of data, knowledge, and commands to other agents, enabling CLIPS applications to initiate interactions autonomously, and respond to requests and results from heterogeneous remote systems. The design and operation of CLIPS agents are illustrated with two distributed applications that integrate CLIPS-based expert systems with other intelligent systems for isolating and mapping problems in the Space Shuttle Launch Processing System at the NASA Kennedy Space Center.

  19. High speed serial communications for control systems

    International Nuclear Information System (INIS)

    Mathieson, D.; Kalbfleisch, C.; Hunt, S.; Low, K.

    1993-01-01

    The Superconducting Super Collider Laboratory is a complex of accelerators being built in Ellis County, Texas. The SSCL control system consists of front-end processors and their associated control points remotely distributed from the Central and Regional control rooms. Control messages passing between these locations require timely (deterministic) distribution. A prototype network consisting of point-to-point links utilizing commercial T1 (1.544 Mb/s) communication boards has been implemented. These dedicated communication links will replace networking services traditionally provided for by shared medium networks like Ethernet(IEEE 802.3) and FDDI(IEEE 802.5). A seamless migration will be achieved by using packet encapsulation based on PPP(Point-to-Point Protocol, RFC 1171). All other networking functions including routing and reliable delivery are still being handled by the usual internet services. A distributed control system that currently uses Ethernet for communication is being re-implemented using these point-to-point links. The authors report on throughput measurements, timing constraints and ease of transition of a point-to-point network

  20. Distributed Access View Integrated Database (DAVID) system

    Science.gov (United States)

    Jacobs, Barry E.

    1991-01-01

    The Distributed Access View Integrated Database (DAVID) System, which was adopted by the Astrophysics Division for their Astrophysics Data System, is a solution to the system heterogeneity problem. The heterogeneous components of the Astrophysics problem is outlined. The Library and Library Consortium levels of the DAVID approach are described. The 'books' and 'kits' level is discussed. The Universal Object Typer Management System level is described. The relation of the DAVID project with the Small Business Innovative Research (SBIR) program is explained.

  1. Distributed simulation of large computer systems

    International Nuclear Information System (INIS)

    Marzolla, M.

    2001-01-01

    Sequential simulation of large complex physical systems is often regarded as a computationally expensive task. In order to speed-up complex discrete-event simulations, the paradigm of Parallel and Distributed Discrete Event Simulation (PDES) has been introduced since the late 70s. The authors analyze the applicability of PDES to the modeling and analysis of large computer system; such systems are increasingly common in the area of High Energy and Nuclear Physics, because many modern experiments make use of large 'compute farms'. Some feasibility tests have been performed on a prototype distributed simulator

  2. Distributed Database Management Systems A Practical Approach

    CERN Document Server

    Rahimi, Saeed K

    2010-01-01

    This book addresses issues related to managing data across a distributed database system. It is unique because it covers traditional database theory and current research, explaining the difficulties in providing a unified user interface and global data dictionary. The book gives implementers guidance on hiding discrepancies across systems and creating the illusion of a single repository for users. It also includes three sample frameworksâ€"implemented using J2SE with JMS, J2EE, and Microsoft .Netâ€"that readers can use to learn how to implement a distributed database management system. IT and

  3. Distributed expert systems for nuclear reactor control

    International Nuclear Information System (INIS)

    Otaduy, P.J.

    1992-01-01

    A network of distributed expert systems is the heart of a prototype supervisory control architecture developed at the Oak Ridge National Laboratory (ORNL) for an advanced multimodular reactor. Eight expert systems encode knowledge on signal acquisition, diagnostics, safeguards, and control strategies in a hybrid rule-based, multiprocessing and object-oriented distributed computing environment. An interactive simulation of a power block consisting of three reactors and one turbine provides a realistic, testbed for performance analysis of the integrated control system in real-time. Implementation details and representative reactor transients are discussed

  4. A Case Study on Distributed Antenna Systems

    DEFF Research Database (Denmark)

    Sørensen, Troels Bundgaard

    2007-01-01

    Passive distributed antenna systems (DASs) consisting of distributed feeder lines or single point antennas are now often installed in large office buildings where they provide efficient coverage throughout the building. More sophisticated DASs with intelligent reuse and the ability to adapt...... is described in terms of algorithms for power allocation and access port assignment, as well as algorithms for (dynamic) channel assignment. After an outline of simulation assumptions, system capacity comparisons are given between the adaptive DAS and a system with fixed channel and access port assignment...

  5. The evolution of a distributed operating system

    NARCIS (Netherlands)

    van Renesse, Robbert; Tanenbaum, Andrew S.; Mullender, Sape J.; Schröder-Preikschat, Wolfgang; Zimmer, Wolfgang

    AMOEBA is a research project to build a true distributed operating system using the object model. Under the COST11-ter MANDIS project this work was extended to cover wide-area networks. Besides describing the system, this paper discusses the successive versions in the implementation of its model,

  6. Distilled Water Distribution Systems. Laboratory Design Notes.

    Science.gov (United States)

    Sell, J.C.

    Factors concerning water distribution systems, including an evaluation of materials and a recommendation of materials best suited for service in typical facilities are discussed. Several installations are discussed in an effort to bring out typical features in selected applications. The following system types are included--(1) industrial…

  7. PFS: a distributed and customizable file system

    OpenAIRE

    Bosch, H.G.P.; Mullender, Sape J.

    1996-01-01

    In this paper we present our ongoing work on the Pegasus File System (PFS), a distributed and customizable file system that can be used for off-line file system experiments and on-line file system storage. PFS is best described as an object-oriented component library from which either a true file system or a file-system simulator can be constructed. Each of the components in the library is easily replaced by another implementation to accommodate a wide range of applications.

  8. Distributed Monitoring System Based on ICINGA

    CERN Multimedia

    Haen, C; Neufeld, N

    2011-01-01

    The LHCb online system relies on a large and heterogeneous I.T. infrastructure : it comprises more than 2000 servers and embedded systems and more than 200 network devices. While for the control and monitoring of detectors, PLCs, and readout boards an industry standard SCADA system PVSSII has been put in production, we use a low level monitoring system to monitor the control infrastructure itself. While our previous system was based on a single central NAGIOS server, our current system uses a distributed ICINGA infrastructure.

  9. Synchronization in Quantum Key Distribution Systems

    Directory of Open Access Journals (Sweden)

    Anton Pljonkin

    2017-10-01

    Full Text Available In the description of quantum key distribution systems, much attention is paid to the operation of quantum cryptography protocols. The main problem is the insufficient study of the synchronization process of quantum key distribution systems. This paper contains a general description of quantum cryptography principles. A two-line fiber-optic quantum key distribution system with phase coding of photon states in transceiver and coding station synchronization mode was examined. A quantum key distribution system was built on the basis of the scheme with automatic compensation of polarization mode distortions. Single-photon avalanche diodes were used as optical radiation detecting devices. It was estimated how the parameters used in quantum key distribution systems of optical detectors affect the detection of the time frame with attenuated optical pulse in synchronization mode with respect to its probabilistic and time-domain characteristics. A design method was given for the process that detects the time frame that includes an optical pulse during synchronization. This paper describes the main quantum communication channel attack methods by removing a portion of optical emission. This paper describes the developed synchronization algorithm that takes into account the time required to restore the photodetector’s operation state after the photon has been registered during synchronization. The computer simulation results of the developed synchronization algorithm were analyzed. The efficiency of the developed algorithm with respect to synchronization process protection from unauthorized gathering of optical emission is demonstrated herein.

  10. Making the Public Distribution System Work

    Directory of Open Access Journals (Sweden)

    Debarshi Das

    2014-02-01

    Full Text Available Drawing on empirical observations of operation of public distribution system in different states of India, the paper constructs a preliminary game theoretic model. It argues that an effective public distribution must be as universal as possible, delivery mechanism of fair price shops should be re- formed, they should be make them commercially viable and that special attention should be paid to PDS at times of high food inflation.

  11. Electricity distribution management Smart Grid system model

    Directory of Open Access Journals (Sweden)

    Wiesław Nowak

    2012-06-01

    Full Text Available This paper presents issues concerning the implementation of Smart Grid solutions in a real distribution network. The main components possible to quick implementation were presented. Realization of these ideas should bring tangible benefi ts to both customers and distribution system operators. Moreover the paper shows selected research results which examine proposed solutions in area of improving supply reliability and reducing energy losses in analysed network.

  12. Control of distributed systems : tutorial and overview

    Czech Academy of Sciences Publication Activity Database

    van Schuppen, J. H.; Boutin, O.; Kempker, P.L.; Komenda, Jan; Masopust, Tomáš; Pambakian, N.; Ran, A.C.M.

    2011-01-01

    Roč. 17, 5-6 (2011), s. 579-602 ISSN 0947-3580 R&D Projects: GA ČR(CZ) GAP103/11/0517; GA ČR(CZ) GPP202/11/P028 Institutional research plan: CEZ:AV0Z10190503 Keywords : distributed system * coordination control * hierarchical control * distributed control * distributed control with communication Subject RIV: BA - General Mathematics Impact factor: 0.817, year: 2011 http://ejc.revuesonline.com/article.jsp?articleId=16873

  13. Design of a distributed control system

    Energy Technology Data Exchange (ETDEWEB)

    Bilous, O [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1959-07-01

    A digital computer is used to evaluate various pressure control systems for a gaseous diffusion cascade. This is an example of a distributed feedback control system. The paper gives a brief discussion of similar cases of distributed or stage wise control systems, which may occur in multiple temperature control of chemical processes. (author) [French] Une calculatrice digitale est utilisee pour evaluer divers systemes de controle de pression pour une cascade de diffusion gazeuse. C'est un exemple de systeme de controle a reaction distribue. Le rapport presente une breve discussion de cas semblables de systemes de controle distribues ou en etage, qui peuvent se presenter dans de nombreux controles de temperature de reactions chimiques. (auteur)

  14. EGSNRC distributed systems on commercial network

    International Nuclear Information System (INIS)

    McCormack, J.M.

    2001-01-01

    Full text: EGSnrc is a Monte Carlo based simulation program for determining radiation dose distribution within a body. Computational times are large as each individual photon path must be calculated and every energy absorption event stored. This means that EGSnrc lends itself to distributed processing, as each photon is independent of the next, and code is included within the package to enable this. EGSnrc is currently only supported on Unix based computer systems, whilst the department has ∼45 Pentium II and III class workstations all operating under Windows NT within a Novell network. This investigation demonstrates the capability of a windows based system to perform distributed computation of EGSnrc. All Unix scripts were modified to work as one single Windows NT batch file. The source code was then compiled using the gcc C compiler (a Windows NT version of the Unix compiler) without modification of the underlying source code. A small Visual Basic program was used as a trigger to start the simulation as a Windows NT service, with Novell Z.E.N. Works to distribute the trigger code to each system. When a trigger was received, the computer began a simulation as a low priority task in such a way that the user did not see anything on the screen, and so the simulation did not slow down the general running of the computer. The results were then transferred to the network, and collated on a central computer. As an unattended system, a calculation can start within 15 minutes of any desired time, calculate the desired results, and return the results for collation. This demonstrated effectively a distributed Windows NT TM EGSnrc system. Simulations must be chosen carefully to ensure that each photon can be considered independent, as photon histories do not get distributed. Each system that was used for EGSnrc was required to be capable of running the full EGSnrc simulation on its own EGSnrc stored the entire result array locally, so a large, high-resolution body required

  15. Neutral particle beam distributed data acquisition system

    International Nuclear Information System (INIS)

    Daly, R.T.; Kraimer, M.R.; Novick, A.H.

    1987-01-01

    A distributed data acquisition system has been designed to support experiments at the Argonne Neutral Particle Beam Accelerator. The system uses a host VAXstation II/GPX computer acting as an experimenter's station linked via Ethernet with multiple MicroVAX IIs and rtVAXs dedicated to acquiring data and controlling hardware at remote sites. This paper describes the hardware design of the system, the applications support software on the host and target computers, and the real-time performance

  16. A Distributed Intelligent System for Emergency Convoy

    Directory of Open Access Journals (Sweden)

    Mohammed Benalla

    2016-09-01

    Full Text Available The general problem that guides this research is the ability to design a distributed intelligent system for guiding the emergency convoys; a solution that will be based on a group of agents and on the analysis of traffic in order to generate collective functional response. It fits into the broader issue of Distributed Artificial System (DAI, which is to operate a cooperatively computer agent into multi-agents system (MAS. This article describes conceptually two fundamental questions of emergency convoys. The first question is dedicated to find a response to the traffic situation (i.e. fluid way, while the second is devoted to the convoy orientation; while putting the point on the distributed and cooperative resolution for the general problem.

  17. The ATLAS Distributed Data Management System & Databases

    CERN Document Server

    Garonne, V; The ATLAS collaboration; Barisits, M; Beermann, T; Vigne, R; Serfon, C

    2013-01-01

    The ATLAS Distributed Data Management (DDM) System is responsible for the global management of petabytes of high energy physics data. The current system, DQ2, has a critical dependency on Relational Database Management Systems (RDBMS), like Oracle. RDBMS are well-suited to enforcing data integrity in online transaction processing applications, however, concerns have been raised about the scalability of its data warehouse-like workload. In particular, analysis of archived data or aggregation of transactional data for summary purposes is problematic. Therefore, we have evaluated new approaches to handle vast amounts of data. We have investigated a class of database technologies commonly referred to as NoSQL databases. This includes distributed filesystems, like HDFS, that support parallel execution of computational tasks on distributed data, as well as schema-less approaches via key-value stores, like HBase. In this talk we will describe our use cases in ATLAS, share our experiences with various databases used ...

  18. Cardea: Dynamic Access Control in Distributed Systems

    Science.gov (United States)

    Lepro, Rebekah

    2004-01-01

    Modern authorization systems span domains of administration, rely on many different authentication sources, and manage complex attributes as part of the authorization process. This . paper presents Cardea, a distributed system that facilitates dynamic access control, as a valuable piece of an inter-operable authorization framework. First, the authorization model employed in Cardea and its functionality goals are examined. Next, critical features of the system architecture and its handling of the authorization process are then examined. Then the S A M L and XACML standards, as incorporated into the system, are analyzed. Finally, the future directions of this project are outlined and connection points with general components of an authorization system are highlighted.

  19. Concurrency control in distributed database systems

    CERN Document Server

    Cellary, W; Gelenbe, E

    1989-01-01

    Distributed Database Systems (DDBS) may be defined as integrated database systems composed of autonomous local databases, geographically distributed and interconnected by a computer network.The purpose of this monograph is to present DDBS concurrency control algorithms and their related performance issues. The most recent results have been taken into consideration. A detailed analysis and selection of these results has been made so as to include those which will promote applications and progress in the field. The application of the methods and algorithms presented is not limited to DDBSs but a

  20. Distributed formation tracking using local coordinate systems

    DEFF Research Database (Denmark)

    Yang, Qingkai; Cao, Ming; Garcia de Marina, Hector

    2018-01-01

    This paper studies the formation tracking problem for multi-agent systems, for which a distributed estimator–controller scheme is designed relying only on the agents’ local coordinate systems such that the centroid of the controlled formation tracks a given trajectory. By introducing a gradient...... descent term into the estimator, the explicit knowledge of the bound of the agents’ speed is not necessary in contrast to existing works, and each agent is able to compute the centroid of the whole formation in finite time. Then, based on the centroid estimation, a distributed control algorithm...

  1. Converters for Distributed Power Generation Systems

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Yang, Yongheng

    2015-01-01

    Power electronics technology has become the enabling technology for the integration of distributed power generation systems (DPGS) such as offshore wind turbine power systems and commercial photovoltaic power plants. Depending on the applications, a vast array of DPGS-based power converter...... topologies has been developed and more are coming into the market in order to achieve an efficient and reliable power conversion from the renewables. In addition, stringent demands from both the distribution system operators and the consumers have been imposed on the renewable-based DPGS. This article...... presents an overview of the power converters for the DPGS, mainly based on wind turbine systems and photovoltaic systems, covering a wide range of applications. Moreover, the modulation schemes and interfacing power filters for the power converters are also exemplified. Finally, the general control...

  2. DC Home Appliances for DC Distribution System

    Directory of Open Access Journals (Sweden)

    MUHAMMAD KAMRAN

    2017-10-01

    Full Text Available This paper strengthens the idea of DC distribution system for DC microgrid consisting of a building of 50 apartments. Since the war of currents AC system has been dominant because of the paucity of research in the protection of the DC system. Now with the advance research in power electronics material and components, generation of electricity is inherently DC as by solar PV, fuel cell and thermoelectric generator that eliminates the rectification process. Transformers are replaced by the power electronics buck-boost converters. DC circuit breakers have solved the protection problems for both DC transmission and distribution system. In this paper 308V DC microgrid is proposed and home appliances (DC internal are modified to operate on 48V DC from DC distribution line. Instead of using universal and induction motors in rotary appliances, BLDC (Brushless DC motors are proposed that are highly efficient with minimum electro-mechanical and no commutation losses. Proposed DC system reduces the power conversion stages, hence diminishes the associated power losses and standby losses that boost the overall system efficiency. So in view of all this a conventional AC system can be replaced by a DC system that has many advantages by cost as well as by performance

  3. Adaptive intelligent power systems: Active distribution networks

    International Nuclear Information System (INIS)

    McDonald, Jim

    2008-01-01

    Electricity networks are extensive and well established. They form a key part of the infrastructure that supports industrialised society. These networks are moving from a period of stability to a time of potentially major transition, driven by a need for old equipment to be replaced, by government policy commitments to cleaner and renewable sources of electricity generation, and by change in the power industry. This paper looks at moves towards active distribution networks. The novel transmission and distribution systems of the future will challenge today's system designs. They will cope with variable voltages and frequencies, and will offer more flexible, sustainable options. Intelligent power networks will need innovation in several key areas of information technology. Active control of flexible, large-scale electrical power systems is required. Protection and control systems will have to react to faults and unusual transient behaviour and ensure recovery after such events. Real-time network simulation and performance analysis will be needed to provide decision support for system operators, and the inputs to energy and distribution management systems. Advanced sensors and measurement will be used to achieve higher degrees of network automation and better system control, while pervasive communications will allow networks to be reconfigured by intelligent systems

  4. Electric distribution systems and embedded generation capacity

    International Nuclear Information System (INIS)

    Calderaro, V.; Galdi, V.; Piccolo, A.; Siano, P.

    2006-01-01

    The main policy issues of European States are sustainable energy supply promotion and liberalization of energy markets, which introduced market competition in electricity production and created support mechanisms to encourage renewable electricity production and consumption. As a result of liberalization, any generator, including small-scale and renewable energy based units, can sell electricity on the free market. In order to meet future sustainability targets, connection of a higher number of Distributed Generation (DG) units to the electrical power system is expected, requiring changes in the design and operation of distribution electricity systems, as well as changes in electricity network regulation. In order to assist distribution system operators in planning and managing DG connections and in maximizing DG penetration and renewable sources exploitation, this paper proposed a reconfiguration methodology based on a Genetic Algorithm (GA), that was tested on a 70-bus system with DG units. The simulation results confirmed that the methodology represents a suitable tool for distribution system operators when dealing with DG capacity expansion and power loss issues, providing information regarding the potential penetration network-wide and allowing maximum exploitation of renewable generation. 35 refs., 4 tabs., 6 figs

  5. Intelligent Control and Operation of Distribution System

    DEFF Research Database (Denmark)

    Bhattarai, Bishnu Prasad

    methodology to ensure efficient control and operation of the future distribution networks. The major scientific challenge is thus to develop control models and strategies to coordinate responses from widely distributed controllable loads and local generations. Detailed models of key Smart Grid (SG) elements...... in this direction but also benefit distribution system operators in the planning and development of the distribution network. The major contributions of this work are described in the following four stages: In the first stage, an intelligent Demand Response (DR) control architecture is developed for coordinating...... the key SG actors, namely consumers, network operators, aggregators, and electricity market entities. A key intent of the architecture is to facilitate market participation of residential consumers and prosumers. A Hierarchical Control Architecture (HCA) having primary, secondary, and tertiary control...

  6. Wireless distributed functional electrical stimulation system

    Directory of Open Access Journals (Sweden)

    Jovičić Nenad S

    2012-08-01

    Full Text Available Abstract Background The control of movement in humans is hierarchical and distributed and uses feedback. An assistive system could be best integrated into the therapy of a human with a central nervous system lesion if the system is controlled in a similar manner. Here, we present a novel wireless architecture and routing protocol for a distributed functional electrical stimulation system that enables control of movement. Methods The new system comprises a set of miniature battery-powered devices with stimulating and sensing functionality mounted on the body of the subject. The devices communicate wirelessly with one coordinator device, which is connected to a host computer. The control algorithm runs on the computer in open- or closed-loop form. A prototype of the system was designed using commercial, off-the-shelf components. The propagation characteristics of electromagnetic waves and the distributed nature of the system were considered during the development of a two-hop routing protocol, which was implemented in the prototype’s software. Results The outcomes of this research include a novel system architecture and routing protocol and a functional prototype based on commercial, off-the-shelf components. A proof-of-concept study was performed on a hemiplegic subject with paresis of the right arm. The subject was tasked with generating a fully functional palmar grasp (closing of the fingers. One node was used to provide this movement, while a second node controlled the activation of extensor muscles to eliminate undesired wrist flexion. The system was tested with the open- and closed-loop control algorithms. Conclusions The system fulfilled technical and application requirements. The novel communication protocol enabled reliable real-time use of the system in both closed- and open-loop forms. The testing on a patient showed that the multi-node system could operate effectively to generate functional movement.

  7. Wireless distributed functional electrical stimulation system.

    Science.gov (United States)

    Jovičić, Nenad S; Saranovac, Lazar V; Popović, Dejan B

    2012-08-09

    The control of movement in humans is hierarchical and distributed and uses feedback. An assistive system could be best integrated into the therapy of a human with a central nervous system lesion if the system is controlled in a similar manner. Here, we present a novel wireless architecture and routing protocol for a distributed functional electrical stimulation system that enables control of movement. The new system comprises a set of miniature battery-powered devices with stimulating and sensing functionality mounted on the body of the subject. The devices communicate wirelessly with one coordinator device, which is connected to a host computer. The control algorithm runs on the computer in open- or closed-loop form. A prototype of the system was designed using commercial, off-the-shelf components. The propagation characteristics of electromagnetic waves and the distributed nature of the system were considered during the development of a two-hop routing protocol, which was implemented in the prototype's software. The outcomes of this research include a novel system architecture and routing protocol and a functional prototype based on commercial, off-the-shelf components. A proof-of-concept study was performed on a hemiplegic subject with paresis of the right arm. The subject was tasked with generating a fully functional palmar grasp (closing of the fingers). One node was used to provide this movement, while a second node controlled the activation of extensor muscles to eliminate undesired wrist flexion. The system was tested with the open- and closed-loop control algorithms. The system fulfilled technical and application requirements. The novel communication protocol enabled reliable real-time use of the system in both closed- and open-loop forms. The testing on a patient showed that the multi-node system could operate effectively to generate functional movement.

  8. Deceit: A flexible distributed file system

    Science.gov (United States)

    Siegel, Alex; Birman, Kenneth; Marzullo, Keith

    1989-01-01

    Deceit, a distributed file system (DFS) being developed at Cornell, focuses on flexible file semantics in relation to efficiency, scalability, and reliability. Deceit servers are interchangeable and collectively provide the illusion of a single, large server machine to any clients of the Deceit service. Non-volatile replicas of each file are stored on a subset of the file servers. The user is able to set parameters on a file to achieve different levels of availability, performance, and one-copy serializability. Deceit also supports a file version control mechanism. In contrast with many recent DFS efforts, Deceit can behave like a plain Sun Network File System (NFS) server and can be used by any NFS client without modifying any client software. The current Deceit prototype uses the ISIS Distributed Programming Environment for all communication and process group management, an approach that reduces system complexity and increases system robustness.

  9. Distributed control system for the FMIT

    International Nuclear Information System (INIS)

    Johnson, J.A.; Machen, D.R.; Suyama, R.M.

    1979-01-01

    The control system for the Fusion Materials Irradiation Test (FMIT) Facility will provide the primary data acquisition, control, and interface components that integrate all of the individual FMIT systems into a functional facility. The control system consists of a distributed computer network, control consoles and instrumentation subsystems. The FMIT Facility will be started, operated and secured from a Central Control Room. All FMIT systems and experimental functions will be monitored from the Central Control Room. The data acquisition and control signals will be handled by a data communications network, which connects dual computers in the Central Control Room to the microcomputers in CAMAC crates near the various subsystems of the facility

  10. Left-forbidding cooperating distributed grammar systems

    Czech Academy of Sciences Publication Activity Database

    Goldefus, F.; Masopust, Tomáš; Meduna, A.

    2010-01-01

    Roč. 411, 40-42 (2010), s. 3661-3667 ISSN 0304-3975 Institutional research plan: CEZ:AV0Z10190503 Keywords : cooperating distributed grammar system * cooperating derivation mode * left-forbidding grammar * generative power * descriptional complexity Subject RIV: BA - General Mathematics Impact factor: 0.838, year: 2010 http://www.sciencedirect.com/science/article/pii/S0304397510003440

  11. Modelling Dynamic Forgetting in Distributed Information Systems

    NARCIS (Netherlands)

    N.F. Höning (Nicolas); M.C. Schut

    2010-01-01

    htmlabstractWe describe and model a new aspect in the design of distributed information systems. We build upon a previously described problem on the microlevel, which asks how quickly agents should discount (forget) their experience: If they cherish their memories, they can build their reports on

  12. Workflow management in large distributed systems

    International Nuclear Information System (INIS)

    Legrand, I; Newman, H; Voicu, R; Dobre, C; Grigoras, C

    2011-01-01

    The MonALISA (Monitoring Agents using a Large Integrated Services Architecture) framework provides a distributed service system capable of controlling and optimizing large-scale, data-intensive applications. An essential part of managing large-scale, distributed data-processing facilities is a monitoring system for computing facilities, storage, networks, and the very large number of applications running on these systems in near realtime. All this monitoring information gathered for all the subsystems is essential for developing the required higher-level services—the components that provide decision support and some degree of automated decisions—and for maintaining and optimizing workflow in large-scale distributed systems. These management and global optimization functions are performed by higher-level agent-based services. We present several applications of MonALISA's higher-level services including optimized dynamic routing, control, data-transfer scheduling, distributed job scheduling, dynamic allocation of storage resource to running jobs and automated management of remote services among a large set of grid facilities.

  13. Wind Power in Electrical Distribution Systems

    DEFF Research Database (Denmark)

    Chen, Zhe

    2013-01-01

    Recent years, wind power is experiencing a rapid growth, large number of wind turbines/wind farms have been installed and connected to power systems. In addition to the large centralised wind farms connected to transmission grids, many distributed wind turbines and wind farms are operated as dist...

  14. Gradient remediability in linear distributed parabolic systems ...

    African Journals Online (AJOL)

    The aim of this paper is the introduction of a new concept that concerned the analysis of a large class of distributed parabolic systems. It is the general concept of gradient remediability. More precisely, we study with respect to the gradient observation, the existence of an input operator (gradient efficient actuators) ensuring ...

  15. Boundary feedback stabilization of distributed parameter systems

    DEFF Research Database (Denmark)

    Pedersen, Michael

    1988-01-01

    The author introduces the method of pseudo-differential stabilization. He notes that the theory of pseudo-differential boundary operators is a fruitful approach to problems arising in control and stabilization theory of distributed-parameter systems. The basic pseudo-differential calculus can...

  16. Distribution system reliability evaluation using credibility theory

    African Journals Online (AJOL)

    Xufeng Xu, Joydeep Mitra

    have found that credibility theory, which broadens the scope of fuzzy set theory, is an effective tool for representing fuzzy events, and have developed a theoretical .... Based on the status of switches, the distribution system can be divided into multiple SPSS, which are connected with tie switches. For example, SPSS.

  17. Trading Freshness for Performance in Distributed Systems

    Science.gov (United States)

    2014-12-01

    C. Hsieh, Deborah A. Wallach, Mike Burrows , Tushar Chandra, Andrew Fikes, and Robert E. Gruber. BigTable: A distributed storage system for structured... Larry Brilliant. Detecting influenza epidemics using search engine query data. Nature, pages 1012–1014, February 2009. 3.2 Goetz Graefe. Write

  18. Workflow management in large distributed systems

    Science.gov (United States)

    Legrand, I.; Newman, H.; Voicu, R.; Dobre, C.; Grigoras, C.

    2011-12-01

    The MonALISA (Monitoring Agents using a Large Integrated Services Architecture) framework provides a distributed service system capable of controlling and optimizing large-scale, data-intensive applications. An essential part of managing large-scale, distributed data-processing facilities is a monitoring system for computing facilities, storage, networks, and the very large number of applications running on these systems in near realtime. All this monitoring information gathered for all the subsystems is essential for developing the required higher-level services—the components that provide decision support and some degree of automated decisions—and for maintaining and optimizing workflow in large-scale distributed systems. These management and global optimization functions are performed by higher-level agent-based services. We present several applications of MonALISA's higher-level services including optimized dynamic routing, control, data-transfer scheduling, distributed job scheduling, dynamic allocation of storage resource to running jobs and automated management of remote services among a large set of grid facilities.

  19. Mansion, A Distributed Multi-Agent System

    NARCIS (Netherlands)

    van t Noordende, G.; Brazier, F.M.; Tanenbaum, A.S.

    2001-01-01

    In this position summary we present work in progress on a worldwide, scalable multi-agent system, based on a paradigm of hyperlinked rooms. The framework offers facilities for managing distribution, security and mobility aspects for both active elements (agents) and passive elements (objects) in the

  20. Programming model for distributed intelligent systems

    Science.gov (United States)

    Sztipanovits, J.; Biegl, C.; Karsai, G.; Bogunovic, N.; Purves, B.; Williams, R.; Christiansen, T.

    1988-01-01

    A programming model and architecture which was developed for the design and implementation of complex, heterogeneous measurement and control systems is described. The Multigraph Architecture integrates artificial intelligence techniques with conventional software technologies, offers a unified framework for distributed and shared memory based parallel computational models and supports multiple programming paradigms. The system can be implemented on different hardware architectures and can be adapted to strongly different applications.

  1. The new bank note distribution system

    OpenAIRE

    Gerrit Bilkes

    1997-01-01

    In this article, the author outlines the recent changes made to the way Canada's bank notes are distributed. The new system allows financial institutions to exchange notes directly with one another at designated points across the country, rather than through Bank of Canada agencies, as was previously the case. The institutions communicate with the Bank of Canada through a computerized inventory-management system. Two Bank of Canada operations centres monitor note quality and supply new notes ...

  2. Planning and Optimization Methods for Active Distribution Systems

    DEFF Research Database (Denmark)

    Abbey, Chad; Baitch, Alex; Bak-Jensen, Birgitte

    distribution planning. Active distribution networks (ADNs) have systems in place to control a combination of distributed energy resources (DERs), defined as generators, loads and storage. With these systems in place, the AND becomes an Active Distribution System (ADS). Distribution system operators (DSOs) have...

  3. The "Family Tree" of Air Distribution Systems

    DEFF Research Database (Denmark)

    Nielsen, Peter V.

    2011-01-01

    In this paper all total volume air distribution principles are addressed based on discussions of air flow pattern in a room with heat sources giving a cooling load. The supply and exhaust air openings are considered to have different locations and sizes in the room, and it is possible to show tha...... conditions which are not used for air distribution in general. A number of experiments with different air distribution systems are addressed, and they illustrate the behaviour at the different conditions discussed in the paper....... that all the known types of air distribution systems are interconnected in a “family tree”. The influence of supplied momentum flow versus buoyancy forces is discussed, and geometries for high ventilation effectiveness are indicated as well as geometries for fully mixed flow. The paper will also show......In this paper all total volume air distribution principles are addressed based on discussions of air flow pattern in a room with heat sources giving a cooling load. The supply and exhaust air openings are considered to have different locations and sizes in the room, and it is possible to show...

  4. Design of distributed systems of hydrolithosphere processes management. A synthesis of distributed management systems

    Science.gov (United States)

    Pershin, I. M.; Pervukhin, D. A.; Ilyushin, Y. V.; Afanaseva, O. V.

    2017-10-01

    The paper considers an important problem of designing distributed systems of hydrolithosphere processes management. The control actions on the hydrolithosphere processes under consideration are implemented by a set of extractive wells. The article shows the method of defining the approximation links for description of the dynamic characteristics of hydrolithosphere processes. The structure of distributed regulators, used in the management systems by the considered processes, is presented. The paper analyses the results of the synthesis of the distributed management system and the results of modelling the closed-loop control system by the parameters of the hydrolithosphere process.

  5. A Comparison Between Publish-and-Subscribe and Client-Server Models in Distributed Control System Networks

    Science.gov (United States)

    Boulanger, Richard P., Jr.; Kwauk, Xian-Min; Stagnaro, Mike; Kliss, Mark (Technical Monitor)

    1998-01-01

    The BIO-Plex control system requires real-time, flexible, and reliable data delivery. There is no simple "off-the-shelf 'solution. However, several commercial packages will be evaluated using a testbed at ARC for publish- and-subscribe and client-server communication architectures. Point-to-point communication architecture is not suitable for real-time BIO-Plex control system. Client-server architecture provides more flexible data delivery. However, it does not provide direct communication among nodes on the network. Publish-and-subscribe implementation allows direct information exchange among nodes on the net, providing the best time-critical communication. In this work Network Data Delivery Service (NDDS) from Real-Time Innovations, Inc. ARTIE will be used to implement publish-and subscribe architecture. It offers update guarantees and deadlines for real-time data delivery. Bridgestone, a data acquisition and control software package from National Instruments, will be tested for client-server arrangement. A microwave incinerator located at ARC will be instrumented with a fieldbus network of control devices. BridgeVIEW will be used to implement an enterprise server. An enterprise network consisting of several nodes at ARC and a WAN connecting ARC and RISC will then be setup to evaluate proposed control system architectures. Several network configurations will be evaluated for fault tolerance, quality of service, reliability and efficiency. Data acquired from these network evaluation tests will then be used to determine preliminary design criteria for the BIO-Plex distributed control system.

  6. Communication Systems and Study Method for Active Distribution Power systems

    DEFF Research Database (Denmark)

    Wei, Mu; Chen, Zhe

    Due to the involvement and evolvement of communication technologies in contemporary power systems, the applications of modern communication technologies in distribution power system are becoming increasingly important. In this paper, the International Organization for Standardization (ISO......) reference seven-layer model of communication systems, and the main communication technologies and protocols on each corresponding layer are introduced. Some newly developed communication techniques, like Ethernet, are discussed with reference to the possible applications in distributed power system....... The suitability of the communication technology to the distribution power system with active renewable energy based generation units is discussed. Subsequently the typical possible communication systems are studied by simulation. In this paper, a novel method of integrating communication system impact into power...

  7. Laser spark distribution and ignition system

    Science.gov (United States)

    Woodruff, Steven [Morgantown, WV; McIntyre, Dustin L [Morgantown, WV

    2008-09-02

    A laser spark distribution and ignition system that reduces the high power optical requirements for use in a laser ignition and distribution system allowing for the use of optical fibers for delivering the low peak energy pumping pulses to a laser amplifier or laser oscillator. An optical distributor distributes and delivers optical pumping energy from an optical pumping source to multiple combustion chambers incorporating laser oscillators or laser amplifiers for inducing a laser spark within a combustion chamber. The optical distributor preferably includes a single rotating mirror or lens which deflects the optical pumping energy from the axis of rotation and into a plurality of distinct optical fibers each connected to a respective laser media or amplifier coupled to an associated combustion chamber. The laser spark generators preferably produce a high peak power laser spark, from a single low power pulse. The laser spark distribution and ignition system has application in natural gas fueled reciprocating engines, turbine combustors, explosives and laser induced breakdown spectroscopy diagnostic sensors.

  8. Distributed systems design using separable communications

    International Nuclear Information System (INIS)

    Capel, A.C.; Yan, G.

    1980-01-01

    One of the promises of distributed systems is the ability to design each process function largely independently of the others, and in many cases locate the resulting hardware in close proximity to the application. The communications architecture for such systems should be approached in the same way, using separable communications facilities to meet individual sets of requirements while at the same time reducing the interactions between functions. Where complete physical separation is not feasible and hardware resource sharing is required, the protocols should be designed emphasizing the logical separation of communication paths. This paper discusses the different types of communications for process control applictions and the parameters which need to be characterized in designing separable communications for distributed systems. (auth)

  9. Overview of the ATLAS distributed computing system

    CERN Document Server

    Elmsheuser, Johannes; The ATLAS collaboration

    2018-01-01

    The CERN ATLAS experiment successfully uses a worldwide computing infrastructure to support the physics program during LHC Run 2. The grid workflow system PanDA routinely manages 250 to 500 thousand concurrently running production and analysis jobs to process simulation and detector data. In total more than 300 PB of data is distributed over more than 150 sites in the WLCG and handled by the ATLAS data management system Rucio. To prepare for the ever growing LHC luminosity in future runs new developments are underway to even more efficiently use opportunistic resources such as HPCs and utilize new technologies. This presentation will review and explain the outline and the performance of the ATLAS distributed computing system and give an outlook to new workflow and data management ideas for the beginning of the LHC Run 3.

  10. Distributed radiation data acquisition system for KAPP

    International Nuclear Information System (INIS)

    Narsaiah, A.; Anantakrishnan, T.S.; Bairi, B.R.

    1992-01-01

    Increased concern for the safety of personnel working in Nuclear Power Stations demands an efficient centralized Radiation Data Acquisition System (RADAS) to monitor different types of radiation at distributed locations of the plant. The system provides a comprehensive picture of radio-activity level distribution in the reactor building to facilitate prompt and correct decision making to take care of any emergency situation. The system is build around an industrial IBM-PC connected to remote intelligent data acquisition units using serial data communication links. To ensure high system availability and ease of maintenance the mechanical moving disk storage has been replaced by solid state memory storage (RAM Disk). Functional CRT displays have been substituted by the assembly of IBM-PC Mother Board with built-in firmware and standard TV Monitor. The computer handles a variety of processing functions which include the conversion to engineering units, checking of alarms, display/printing of plant radiation level status and system diagnostics. Intelligent terminals have been provided with graphic and text formatting capabilities. A hot standby computer connected to analog and digital inputs takes over the system functions on the failure of the host system. Modular software written in the higher level C-language runs under a standard real-time operating system Kernel. This provides for easy modification and expandability at site. Based on the experience of its commissioning at Kakrapar Power Station a new compact version is being designed for a specific application in another class of reactor. (author). 3 refs., 1 fig

  11. 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

  12. Distributed intelligent urban environment monitoring system

    Science.gov (United States)

    Du, Jinsong; Wang, Wei; Gao, Jie; Cong, Rigang

    2018-02-01

    The current environmental pollution and destruction have developed into a world-wide major social problem that threatens human survival and development. Environmental monitoring is the prerequisite and basis of environmental governance, but overall, the current environmental monitoring system is facing a series of problems. Based on the electrochemical sensor, this paper designs a small, low-cost, easy to layout urban environmental quality monitoring terminal, and multi-terminal constitutes a distributed network. The system has been small-scale demonstration applications and has confirmed that the system is suitable for large-scale promotion

  13. General distributed control system for fusion experiments

    International Nuclear Information System (INIS)

    Klingner, P.L.; Levings, S.J.; Wilkins, R.W.

    1986-01-01

    A general control system using distributed LSI-11 microprocessors is being developed. Common software residues in each LSI-11 and is tailored to an application by control specifications downloaded from a host computer. The microprocessors, their control interfaces, and the micro-to-host communications are CAMAC based. The host computer also supports an operator interface, coordination of multiple microprocessors, and utilities to create and maintain the control specifications. Typical applications include monitoring safety interlocks as well as controlling vacuum systems, high voltage charging systems, and diagnostics

  14. Distributed parallel messaging for multiprocessor systems

    Science.gov (United States)

    Chen, Dong; Heidelberger, Philip; Salapura, Valentina; Senger, Robert M; Steinmacher-Burrow, Burhard; Sugawara, Yutaka

    2013-06-04

    A method and apparatus for distributed parallel messaging in a parallel computing system. The apparatus includes, at each node of a multiprocessor network, multiple injection messaging engine units and reception messaging engine units, each implementing a DMA engine and each supporting both multiple packet injection into and multiple reception from a network, in parallel. The reception side of the messaging unit (MU) includes a switch interface enabling writing of data of a packet received from the network to the memory system. The transmission side of the messaging unit, includes switch interface for reading from the memory system when injecting packets into the network.

  15. Distributed computer controls for accelerator systems

    International Nuclear Information System (INIS)

    Moore, T.L.

    1988-09-01

    A distributed control system has been designed and installed at the Lawrence Livermore National Laboratory Multi-user Tandem Facility using an extremely modular approach in hardware and software. The two tiered, geographically organized design allowed total system implementation with four months with a computer and instrumentation cost of approximately $100K. Since the system structure is modular, application to a variety of facilities is possible. Such a system allows rethinking and operational style of the facilities, making possible highly reproducible and unattended operation. The impact of industry standards, i.e., UNIX, CAMAC, and IEEE-802.3, and the use of a graphics-oriented controls software suite allowed the efficient implementation of the system. The definition, design, implementation, operation and total system performance will be discussed. 3 refs

  16. Distributed computer controls for accelerator systems

    Science.gov (United States)

    Moore, T. L.

    1989-04-01

    A distributed control system has been designed and installed at the Lawrence Livermore National Laboratory Multiuser Tandem Facility using an extremely modular approach in hardware and software. The two tiered, geographically organized design allowed total system implantation within four months with a computer and instrumentation cost of approximately $100k. Since the system structure is modular, application to a variety of facilities is possible. Such a system allows rethinking of operational style of the facilities, making possible highly reproducible and unattended operation. The impact of industry standards, i.e., UNIX, CAMAC, and IEEE-802.3, and the use of a graphics-oriented controls software suite allowed the effective implementation of the system. The definition, design, implementation, operation and total system performance will be discussed.

  17. Distributed computer controls for accelerator systems

    International Nuclear Information System (INIS)

    Moore, T.L.

    1989-01-01

    A distributed control system has been designed and installed at the Lawrence Livermore National Laboratory Multiuser Tandem Facility using an extremely modular approach in hardware and software. The two tiered, geographically organized design allowed total system implantation within four months with a computer and instrumentation cost of approximately $100k. Since the system structure is modular, application to a variety of facilities is possible. Such a system allows rethinking of operational style of the facilities, making possible highly reproducible and unattended operation. The impact of industry standards, i.e., UNIX, CAMAC, and IEEE-802.3, and the use of a graphics-oriented controls software suite allowed the effective implementation of the system. The definition, design, implementation, operation and total system performance will be discussed. (orig.)

  18. 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.)

  19. Representation of chromatic distribution for lighting system

    Science.gov (United States)

    Rossi, Maurizio; Musante, Fulvio

    2015-01-01

    For the luminaire manufacturer, the measurement of the lighting intensity distribution (LID) emitted by lighting fixture is based on photometry. So light is measured as an achromatic value of intensity and there is no the possibility to discriminate the measurement of white vs. colored light. At the Laboratorio Luce of Politecnico di Milano a new instrument for the measurement of spectral radiant intensities distribution for lighting system has been built: the goniospectra- radiometer. This new measuring tool is based on a traditional mirror gonio-photometer with a CCD spectraradiometer controlled by a PC. Beside the traditional representation of photometric distribution we have introduced a new representation where, in addition to the information about the distribution of luminous intensity in space, new details about the chromaticity characteristic of the light sources have been implemented. Some of the results of this research have been applied in developing and testing a new line of lighting system "My White Light" (the research project "Light, Environment and Humans" funded in the Italian Lombardy region Metadistretti Design Research Program involving Politecnico di Milano, Artemide, Danese, and some other SME of the Lighting Design district), giving scientific notions and applicative in order to support the assumption that colored light sources can be used for the realization of interior luminaries that, other than just have low power consumption and long life, may positively affect the mood of people.

  20. Power quality in electric distribution systems

    International Nuclear Information System (INIS)

    Mohamed, A.A.S.

    2005-01-01

    the power quality of the electric system is defined by the constant values of the voltage and frequency, the good value of the power factor close to unity, and balanced three phase voltages and currents. capacitors are widely installed in distribution systems for reactive power compensation to achieve power and energy loss reduction, voltage regulation and system capacity release. the extent of these benefits depends greatly on low the capacitors are placed on the system . the problem of how to place capacitors on the system such that these benefits are achieved and / or maximized against the cost associated with the capacitor placement is termed the general capacitor placement problem.the presented mathematical model has been developed to determine the size, number, and location of fixed capacitor banks that will maximize the saving derived from reduction in peak power and energy loss, and that will minimize the capital and installation costs of capacitors

  1. Identification of systems with distributed parameters

    International Nuclear Information System (INIS)

    Moret, J.M.

    1990-10-01

    The problem of finding a model for the dynamical response of a system with distributed parameters based on measured data is addressed. First a mathematical formalism is developed in order to obtain the specific properties of such a system. Then a linear iterative identification algorithm is proposed that includes these properties, and that produces better results than usual non linear minimisation techniques. This algorithm is further improved by an original data decimation that allow to artificially increase the sampling period without losing between sample information. These algorithms are tested with real laboratory data

  2. Neutron chain length distributions in subcritical systems

    International Nuclear Information System (INIS)

    Nolen, S.D.; Spriggs, G.

    1999-01-01

    In this paper, the authors present the results of the chain-length distribution as a function of k in subcritical systems. These results were obtained from a point Monte Carlo code and a three-dimensional Monte Carlo code, MC++. Based on these results, they then attempt to explain why several of the common neutron noise techniques, such as the Rossi-α and Feynman's variance-to-mean techniques, are difficult to perform in highly subcritical systems using low-efficiency detectors

  3. Distributed Control in Multi-Vehicle Systems

    Directory of Open Access Journals (Sweden)

    Paul A. Avery

    2013-12-01

    Full Text Available The Southwest Research Institute (SwRI Mobile Autonomous Robotics Technology Initiative (MARTI program has enabled the development of fully-autonomous passenger-sized commercial vehicles and military tactical vehicles, as well as the development of cooperative vehicle behaviors, such as cooperative sensor sharing and cooperative convoy operations. The program has also developed behaviors to interface intelligent vehicles with intelligent road-side devices. The development of intelligent vehicle behaviors cannot be approached as stand-alone phenomena; rather, they must be understood within a context of the broader traffic system dynamics. The study of other complex systems has shown that system-level behaviors emerge as a result of the spatio-temporal dynamics within a system's constituent parts. The design of such systems must therefore account for both the system-level emergent behavior, as well as behaviors of individuals within the system. It has also become clear over the past several years, for both of these domains, that human trust in the behavior of individual vehicles is paramount to broader technology adoption. This paper examines the interplay between individual vehicle capabilities, vehicle connectivity, and emergent system behaviors, and presents some considerations for a distributed control paradigm in a multi-vehicle system.

  4. Software Quality Measurement for Distributed Systems. Volume 3. Distributed Computing Systems: Impact on Software Quality.

    Science.gov (United States)

    1983-07-01

    Distributed Computing Systems impact DrnwrR - aehR on Sotwar Quaity. PERFORMING 010. REPORT NUMBER 7. AUTNOW) S. CONTRACT OR GRANT "UMBER(*)IS ThomasY...C31 Application", "Space Systems Network", "Need for Distributed Database Management", and "Adaptive Routing". This is discussed in the last para ...data reduction, buffering, encryption, and error detection and correction functions. Examples of such data streams include imagery data, video

  5. Smart Operations in Distributed Energy Resources System

    Science.gov (United States)

    Wei, Li; Jie, Shu; Zhang-XianYong; Qing, Zhou

    Smart grid capabilities are being proposed to help solve the challenges concerning system operations due to that the trade-offs between energy and environmental needs will be constantly negotiated while a reliable supply of electricity needs even greater assurance in case of that threats of disruption have risen. This paper mainly explores models for distributed energy resources system (DG, storage, and load),and also reviews the evolving nature of electricity markets to deal with this complexity and a change of emphasis on signals from these markets to affect power system control. Smart grid capabilities will also impact reliable operations, while cyber security issues must be solved as a culture change that influences all system design, implementation, and maintenance. Lastly, the paper explores significant questions for further research and the need for a simulation environment that supports such investigation and informs deployments to mitigate operational issues as they arise.

  6. Security of practical quantum key distribution systems

    Energy Technology Data Exchange (ETDEWEB)

    Jain, Nitin

    2015-02-24

    This thesis deals with practical security aspects of quantum key distribution (QKD) systems. At the heart of the theoretical model of any QKD system lies a quantum-mechanical security proof that guarantees perfect secrecy of messages - based on certain assumptions. However, in practice, deviations between the theoretical model and the physical implementation could be exploited by an attacker to break the security of the system. These deviations may arise from technical limitations and operational imperfections in the physical implementation and/or unrealistic assumptions and insufficient constraints in the theoretical model. In this thesis, we experimentally investigate in depth several such deviations. We demonstrate the resultant vulnerabilities via proof-of-principle attacks on a commercial QKD system from ID Quantique. We also propose countermeasures against the investigated loopholes to secure both existing and future QKD implementations.

  7. States of Cybersecurity: Electricity Distribution System Discussions

    Energy Technology Data Exchange (ETDEWEB)

    Pena, Ivonne [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ingram, Michael [National Renewable Energy Lab. (NREL), Golden, CO (United States); Martin, Maurice [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2017-03-16

    State and local entities that oversee the reliable, affordable provision of electricity are faced with growing and evolving threats from cybersecurity risks to our nation's electricity distribution system. All-hazards system resilience is a shared responsibility among electric utilities and their regulators or policy-setting boards of directors. Cybersecurity presents new challenges and should be a focus for states, local governments, and Native American tribes that are developing energy-assurance plans to protect critical infrastructure. This research sought to investigate the implementation of governance and policy at the distribution utility level that facilitates cybersecurity preparedness to inform the U.S. Department of Energy (DOE), Office of Energy Policy and Systems Analysis; states; local governments; and other stakeholders on the challenges, gaps, and opportunities that may exist for future analysis. The need is urgent to identify the challenges and inconsistencies in how cybersecurity practices are being applied across the United States to inform the development of best practices, mitigations, and future research and development investments in securing the electricity infrastructure. By examining the current practices and applications of cybersecurity preparedness, this report seeks to identify the challenges and persistent gaps between policy and execution and reflect the underlying motivations of distinct utility structures as they play out at the local level. This study aims to create an initial baseline of cybersecurity preparedness within the distribution electricity sector. The focus of this study is on distribution utilities not bound by the cybersecurity guidelines of the North American Electric Reliability Corporation (NERC) to examine the range of mechanisms taken by state regulators, city councils that own municipal utilities, and boards of directors of rural cooperatives.

  8. FRIB Cryogenic Distribution System and Status

    Energy Technology Data Exchange (ETDEWEB)

    Ganni, Venkatarao [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Dixon, Kelly D. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Laverdure, Nathaniel A. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Yang, Shuo [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Nellis, Timothy [Michigan State Univ., East Lansing, MI (United States); Jones, S. [Michigan State Univ., East Lansing, MI (United States); Casagrande, Fabio [Michigan State Univ., East Lansing, MI (United States)

    2015-12-01

    The MSU-FRIB cryogenic distribution system supports the 2 K primary, 4 K primary, and 35 - 55 K shield operation of more than 70 loads in the accelerator and the experimental areas. It is based on JLab and SNS experience with bayonet-type disconnects between the loads and the distribution system for phased commissioning and maintenance. The linac transfer line, which features three separate transfer line segments for additional independence during phased commissioning at 4 K and 2 K, connects the folded arrangement of 49 cryomodules and 4 superconducting dipole magnets and a fourth transfer line supports the separator area cryo loads. The pressure reliefs for the transfer line process lines, located in the refrigeration room outside the tunnel/accelerator area, are piped to be vented outdoors. The transfer line designs integrate supply and return flow paths into a combined vacuum space. The main linac distribution segments are produced in a small number of standard configurations; a prototype of one such configuration has been fabricated at Jefferson Lab and has been installed at MSU to support testing of a prototype FRIB cryomodule.

  9. A distributed clinical decision support system architecture

    Directory of Open Access Journals (Sweden)

    Shaker H. El-Sappagh

    2014-01-01

    Full Text Available This paper proposes an open and distributed clinical decision support system architecture. This technical architecture takes advantage of Electronic Health Record (EHR, data mining techniques, clinical databases, domain expert knowledge bases, available technologies and standards to provide decision-making support for healthcare professionals. The architecture will work extremely well in distributed EHR environments in which each hospital has its own local EHR, and it satisfies the compatibility, interoperability and scalability objectives of an EHR. The system will also have a set of distributed knowledge bases. Each knowledge base will be specialized in a specific domain (i.e., heart disease, and the model achieves cooperation, integration and interoperability between these knowledge bases. Moreover, the model ensures that all knowledge bases are up-to-date by connecting data mining engines to each local knowledge base. These data mining engines continuously mine EHR databases to extract the most recent knowledge, to standardize it and to add it to the knowledge bases. This framework is expected to improve the quality of healthcare, reducing medical errors and guaranteeing the safety of patients by helping clinicians to make correct, accurate, knowledgeable and timely decisions.

  10. A remote tracing facility for distributed systems

    International Nuclear Information System (INIS)

    Ehm, F.; Dworak, A.

    2012-01-01

    Today, CERN's control system is built upon a large number of C++ and Java services producing log events. In such a largely distributed environment these log messages are essential for problem recognition and tracing. Tracing is therefore vital for operation as understanding an issue in a subsystem means analysing log events in an efficient and fast manner. At present 3150 device servers are deployed on 1600 disk-less front-ends and they send their log messages via the network to an in-house developed central server which, in turn, saves them to files. However, this solution is not able to provide several highly desired features and has performance limitations which led to the development of a new solution. The new distributed tracing facility fulfills these requirements by taking advantage of the Streaming Text Oriented Messaging Protocol (STOMP) and ActiveMQ as the transport layer. The system not only allows storing critical log events centrally in files or in a database but also allows other clients (e.g. graphical interfaces) to read the same events concurrently by using the provided Java API. Thanks to the ActiveMQ broker technology the system can easily be extended to clients implemented in other languages and it is highly scalable in terms of performance. Long running tests have shown that the system can handle up to 10.000 messages/second. (authors)

  11. Distance Protection for Microgrids in Distribution System

    DEFF Research Database (Denmark)

    Lin, Hengwei; Liu, Chengxi; Guerrero, Josep M.

    2015-01-01

    protection decreased. This paper adopts distance protection for one mid-voltage level microgrid in Aalborg, Denmark. Different operation modes of the network are analyzed and tested in the paper. The simulation results show that the variations of the fault currents seen by the forward relays are much larger...... than the backward relays. Meanwhile, the fault currents change little with the randomness of renewable energy except the intermittence. Finally, it shows that the designed distance protection has satisfactory performance to clear the various faults.......Owing to the increasing penetration of distributed generation, there are some challenges for the conventional protection in distribution system. Bidirectional power flow and variable fault current because of the various operation modes may lead to the selectivity and sensitivity of the overcurrent...

  12. DAD - Distributed Adamo Database system at Hermes

    International Nuclear Information System (INIS)

    Wander, W.; Dueren, M.; Ferstl, M.; Green, P.; Potterveld, D.; Welch, P.

    1996-01-01

    Software development for the HERMES experiment faces the challenges of many other experiments in modern High Energy Physics: Complex data structures and relationships have to be processed at high I/O rate. Experimental control and data analysis are done on a distributed environment of CPUs with various operating systems and requires access to different time dependent databases like calibration and geometry. Slow and experimental control have a need for flexible inter-process-communication. Program development is done in different programming languages where interfaces to the libraries should not restrict the capacities of the language. The needs of handling complex data structures are fulfilled by the ADAMO entity relationship model. Mixed language programming can be provided using the CFORTRAN package. DAD, the Distributed ADAMO Database library, was developed to provide the I/O and database functionality requirements. (author)

  13. Building a generalized distributed system model

    Science.gov (United States)

    Mukkamala, R.

    1993-01-01

    The key elements in the 1992-93 period of the project are the following: (1) extensive use of the simulator to implement and test - concurrency control algorithms, interactive user interface, and replica control algorithms; and (2) investigations into the applicability of data and process replication in real-time systems. In the 1993-94 period of the project, we intend to accomplish the following: (1) concentrate on efforts to investigate the effects of data and process replication on hard and soft real-time systems - especially we will concentrate on the impact of semantic-based consistency control schemes on a distributed real-time system in terms of improved reliability, improved availability, better resource utilization, and reduced missed task deadlines; and (2) use the prototype to verify the theoretically predicted performance of locking protocols, etc.

  14. LHCb: Monitoring the DIRAC Distribution System

    CERN Multimedia

    Nandakumar, R; Santinelli, R

    2009-01-01

    DIRAC is the LHCb gateway to any computing grid infrastructure (currently supporting WLCG) and is intended to reliably run large data mining activities. The DIRAC system consists of various services (which wait to be contacted to perform actions) and agents (which carry out periodic activities) to direct jobs as required. An important part of ensuring the reliability of the infrastructure is the monitoring and logging of these DIRAC distributed systems. The monitoring is done collecting information from two sources - one is from pinging the services or by keeping track of the regular heartbeats of the agents, and the other from the analysis of the error messages generated by both agents and services and collected by the logging system. This allows us to ensure that he components are running properly and to collect useful information regarding their operations. The process status monitoring is displayed using the SLS sensor mechanism which also automatically allows one to plot various quantities and also keep ...

  15. Distributed Online Learning in Social Recommender Systems

    Science.gov (United States)

    Tekin, Cem; Zhang, Simpson; van der Schaar, Mihaela

    2014-08-01

    In this paper, we consider decentralized sequential decision making in distributed online recommender systems, where items are recommended to users based on their search query as well as their specific background including history of bought items, gender and age, all of which comprise the context information of the user. In contrast to centralized recommender systems, in which there is a single centralized seller who has access to the complete inventory of items as well as the complete record of sales and user information, in decentralized recommender systems each seller/learner only has access to the inventory of items and user information for its own products and not the products and user information of other sellers, but can get commission if it sells an item of another seller. Therefore the sellers must distributedly find out for an incoming user which items to recommend (from the set of own items or items of another seller), in order to maximize the revenue from own sales and commissions. We formulate this problem as a cooperative contextual bandit problem, analytically bound the performance of the sellers compared to the best recommendation strategy given the complete realization of user arrivals and the inventory of items, as well as the context-dependent purchase probabilities of each item, and verify our results via numerical examples on a distributed data set adapted based on Amazon data. We evaluate the dependence of the performance of a seller on the inventory of items the seller has, the number of connections it has with the other sellers, and the commissions which the seller gets by selling items of other sellers to its users.

  16. Distributed design approach in persistent identifiers systems

    Science.gov (United States)

    Golodoniuc, Pavel; Car, Nicholas; Klump, Jens

    2017-04-01

    The need to identify both digital and physical objects is ubiquitous in our society. Past and present persistent identifier (PID) systems, of which there is a great variety in terms of technical and social implementations, have evolved with the advent of the Internet, which has allowed for globally unique and globally resolvable identifiers. PID systems have catered for identifier uniqueness, integrity, persistence, and trustworthiness, regardless of the identifier's application domain, the scope of which has expanded significantly in the past two decades. Since many PID systems have been largely conceived and developed by small communities, or even a single organisation, they have faced challenges in gaining widespread adoption and, most importantly, the ability to survive change of technology. This has left a legacy of identifiers that still exist and are being used but which have lost their resolution service. We believe that one of the causes of once successful PID systems fading is their reliance on a centralised technical infrastructure or a governing authority. Golodoniuc et al. (2016) proposed an approach to the development of PID systems that combines the use of (a) the Handle system, as a distributed system for the registration and first-degree resolution of persistent identifiers, and (b) the PID Service (Golodoniuc et al., 2015), to enable fine-grained resolution to different information object representations. The proposed approach solved the problem of guaranteed first-degree resolution of identifiers, but left fine-grained resolution and information delivery under the control of a single authoritative source, posing risk to the long-term availability of information resources. Herein, we develop these approaches further and explore the potential of large-scale decentralisation at all levels: (i) persistent identifiers and information resources registration; (ii) identifier resolution; and (iii) data delivery. To achieve large-scale decentralisation

  17. Grand Challenges in Space Technology: Distributed Satellite Systems

    National Research Council Canada - National Science Library

    Miller, David

    2001-01-01

    The MITIAFRL Distributed Satellite Systems program examines the motivation, analysis and development of technology associated with the distribution of assets and functionality over a number of cooperating satellites...

  18. The physics of distributed information systems

    International Nuclear Information System (INIS)

    Aurell, Erik

    2013-01-01

    This paper aims to introduce Distributed Systems as a field where the ideas and methods of physics can potentially be applied, and to provide entry points to a wide literature. The contributions of Leslie Lamport, inspired by Relativity Theory, and of Edsger Dijkstra, which has the flavor of a growth process, are discussed at some length. The intent of the author is primarily to stimulate interest in the statistical physics community, and the discussions are therefore framed in a non-technical language; the author apologizes in advance to readers from the computer science side for the unavoidable impreciseness and ambiguities

  19. Distributed, cooperating knowledge-based systems

    Science.gov (United States)

    Truszkowski, Walt

    1991-01-01

    Some current research in the development and application of distributed, cooperating knowledge-based systems technology is addressed. The focus of the current research is the spacecraft ground operations environment. The underlying hypothesis is that, because of the increasing size, complexity, and cost of planned systems, conventional procedural approaches to the architecture of automated systems will give way to a more comprehensive knowledge-based approach. A hallmark of these future systems will be the integration of multiple knowledge-based agents which understand the operational goals of the system and cooperate with each other and the humans in the loop to attain the goals. The current work includes the development of a reference model for knowledge-base management, the development of a formal model of cooperating knowledge-based agents, the use of testbed for prototyping and evaluating various knowledge-based concepts, and beginning work on the establishment of an object-oriented model of an intelligent end-to-end (spacecraft to user) system. An introductory discussion of these activities is presented, the major concepts and principles being investigated are highlighted, and their potential use in other application domains is indicated.

  20. modeling workflow management in a distributed computing system

    African Journals Online (AJOL)

    Dr Obe

    communication system, which allows for computerized support. ... Keywords: Distributed computing system; Petri nets;Workflow management. 1. ... A distributed operating system usually .... the questionnaire is returned with invalid data,.

  1. Distributed optimization for systems design : an augmented Lagrangian coordination method

    NARCIS (Netherlands)

    Tosserams, S.

    2008-01-01

    This thesis presents a coordination method for the distributed design optimization of engineering systems. The design of advanced engineering systems such as aircrafts, automated distribution centers, and microelectromechanical systems (MEMS) involves multiple components that together realize the

  2. Test report light duty utility arm power distribution system (PDS)

    International Nuclear Information System (INIS)

    Clark, D.A.

    1996-01-01

    The Light Duty Utility Arm (LDUA) Power Distribution System has completed vendor and post-delivery acceptance testing. The Power Distribution System has been found to be acceptable and is now ready for integration with the overall LDUA system

  3. Distribution system costs associated with the deployment of photovoltaic systems

    Energy Technology Data Exchange (ETDEWEB)

    Horowitz, Kelsey A. W.; Palmintier, Bryan; Mather, Barry; Denholm, Paul

    2018-07-01

    The broadening of our energy system to include increasing amounts of wind and solar has led to significant debate about the total costs and benefits associated with different types of generators - with potentially far-reaching policy implications. This has included debate about the cost associated with integrating these generators onto the electric grid. For photovoltaics (PV), this encompasses costs incurred on both the bulk power and distribution systems, as well as the value provided to them. These costs and benefits, in particular those associated with integrating PV onto the distribution system, are not well understood. We seek to advance the state of understanding of 'grid integration costs' for the distribution system by reviewing prior literature and outlining a transparent, bottom-up approach that can be used to calculate these costs. We provide a clear delineation of costs to integrate PV in to the distribution system within the larger context of total costs and benefits associated with PV generators. We emphasize that these costs are situationally dependent, and that a single 'cost of integration' cannot be obtained. We additionally emphasize that benefits must be considered when evaluating the competitiveness of the technology in a given situation.

  4. Distribution in flowing reaction-diffusion systems

    KAUST Repository

    Kamimura, Atsushi; Herrmann, Hans J.; Ito, Nobuyasu

    2009-01-01

    A power-law distribution is found in the density profile of reacting systems A+B→C+D and 2A→2C under a flow in two and three dimensions. Different densities of reactants A and B are fixed at both ends. For the reaction A+B, the concentration of reactants asymptotically decay in space as x-1/2 and x-3/4 in two dimensions and three dimensions, respectively. For 2A, it decays as log (x) /x in two dimensions. The decay of A+B is explained considering the effect of segregation of reactants in the isotropic case. The decay for 2A is explained by the marginal behavior of two-dimensional diffusion. A logarithmic divergence of the diffusion constant with system size is found in two dimensions. © 2009 The American Physical Society.

  5. Distribution in flowing reaction-diffusion systems

    KAUST Repository

    Kamimura, Atsushi

    2009-12-28

    A power-law distribution is found in the density profile of reacting systems A+B→C+D and 2A→2C under a flow in two and three dimensions. Different densities of reactants A and B are fixed at both ends. For the reaction A+B, the concentration of reactants asymptotically decay in space as x-1/2 and x-3/4 in two dimensions and three dimensions, respectively. For 2A, it decays as log (x) /x in two dimensions. The decay of A+B is explained considering the effect of segregation of reactants in the isotropic case. The decay for 2A is explained by the marginal behavior of two-dimensional diffusion. A logarithmic divergence of the diffusion constant with system size is found in two dimensions. © 2009 The American Physical Society.

  6. Distributed fiber optic moisture intrusion sensing system

    Science.gov (United States)

    Weiss, Jonathan D.

    2003-06-24

    Method and system for monitoring and identifying moisture intrusion in soil such as is contained in landfills housing radioactive and/or hazardous waste. The invention utilizes the principle that moist or wet soil has a higher thermal conductance than dry soil. The invention employs optical time delay reflectometry in connection with a distributed temperature sensing system together with heating means in order to identify discrete areas within a volume of soil wherein temperature is lower. According to the invention an optical element and, optionally, a heating element may be included in a cable or other similar structure and arranged in a serpentine fashion within a volume of soil to achieve efficient temperature detection across a large area or three dimensional volume of soil. Remediation, moisture countermeasures, or other responsive action may then be coordinated based on the assumption that cooler regions within a soil volume may signal moisture intrusion where those regions are located.

  7. System Integration of Distributed Energy Resources

    DEFF Research Database (Denmark)

    Nyeng, Preben

    units, including the ICT solutions that can facilitate the integration. Specifically, the international standard "IEC 61850-7-420 Communications systems for Distributed Energy Resources" is considered as a possible brick in the solution. This standard has undergone continuous development....... It is therefore investigated in this project how ancillary services can be provided by alternatives to central power stations, and to what extent these can be integrated in the system by means of market-based methods. Particular emphasis is put on automatic solutions, which is particularly relevant for small......, and this project has actively contributed to its further development and improvements. Different types of integration methods are investigated in the project. Some are based on local measurement and control, e.g. by measuring the grid frequency, whereas others are based on direct remote control or market...

  8. CODA: A scalable, distributed data acquisition system

    International Nuclear Information System (INIS)

    Watson, W.A. III; Chen, J.; Heyes, G.; Jastrzembski, E.; Quarrie, D.

    1994-01-01

    A new data acquisition system has been designed for physics experiments scheduled to run at CEBAF starting in the summer of 1994. This system runs on Unix workstations connected via ethernet, FDDI, or other network hardware to multiple intelligent front end crates -- VME, CAMAC or FASTBUS. CAMAC crates may either contain intelligent processors, or may be interfaced to VME. The system is modular and scalable, from a single front end crate and one workstation linked by ethernet, to as may as 32 clusters of front end crates ultimately connected via a high speed network to a set of analysis workstations. The system includes an extensible, device independent slow controls package with drivers for CAMAC, VME, and high voltage crates, as well as a link to CEBAF accelerator controls. All distributed processes are managed by standard remote procedure calls propagating change-of-state requests, or reading and writing program variables. Custom components may be easily integrated. The system is portable to any front end processor running the VxWorks real-time kernel, and to most workstations supplying a few standard facilities such as rsh and X-windows, and Motif and socket libraries. Sample implementations exist for 2 Unix workstation families connected via ethernet or FDDI to VME (with interfaces to FASTBUS or CAMAC), and via ethernet to FASTBUS or CAMAC

  9. MDSplus automated build and distribution system

    Energy Technology Data Exchange (ETDEWEB)

    Fredian, T., E-mail: twf@psfc.mit.edu [Massachusetts Institute of Technology, 175 Albany Street, Cambridge, MA 02139 (United States); Stillerman, J. [Massachusetts Institute of Technology, 175 Albany Street, Cambridge, MA 02139 (United States); Manduchi, G. [Consorzio RFX, Euratom-ENEA Association, Corso Stati Uniti 4, Padova 35127 (Italy)

    2014-05-15

    Support of the MDSplus data handling system has been enhanced by the addition of an automated build system which does nightly builds of MDSplus for many computer platforms producing software packages which can now be downloaded using a web browser or via package repositories suitable for automatic updating. The build system was implemented using an extensible continuous integration server product called Hudson which schedules software builds on a collection of VMware based virtual machines. New releases are created based on updates via the MDSplus cvs code repository and versioning are managed using cvs tags and branches. Currently stable, beta and alpha releases of MDSplus are maintained for eleven different platforms including Windows, MacOSX, RedHat Enterprise Linux, Fedora, Ubuntu and Solaris. For some of these platforms, MDSplus packaging has been broken into functional modules so users can pick and choose which MDSplus features they want to install. An added feature to the latest Linux based platforms is the use of package dependencies. When installing MDSplus from the package repositories, any additional required packages used by MDSplus will be installed automatically greatly simplifying the installation of MDSplus. This paper will describe the MDSplus package automated build and distribution system.

  10. MDSplus automated build and distribution system

    International Nuclear Information System (INIS)

    Fredian, T.; Stillerman, J.; Manduchi, G.

    2014-01-01

    Support of the MDSplus data handling system has been enhanced by the addition of an automated build system which does nightly builds of MDSplus for many computer platforms producing software packages which can now be downloaded using a web browser or via package repositories suitable for automatic updating. The build system was implemented using an extensible continuous integration server product called Hudson which schedules software builds on a collection of VMware based virtual machines. New releases are created based on updates via the MDSplus cvs code repository and versioning are managed using cvs tags and branches. Currently stable, beta and alpha releases of MDSplus are maintained for eleven different platforms including Windows, MacOSX, RedHat Enterprise Linux, Fedora, Ubuntu and Solaris. For some of these platforms, MDSplus packaging has been broken into functional modules so users can pick and choose which MDSplus features they want to install. An added feature to the latest Linux based platforms is the use of package dependencies. When installing MDSplus from the package repositories, any additional required packages used by MDSplus will be installed automatically greatly simplifying the installation of MDSplus. This paper will describe the MDSplus package automated build and distribution system

  11. Distributed monitoring system based on Icinga

    International Nuclear Information System (INIS)

    Haen, C.; Bonaccorsi, E.; Neufeld, N.

    2012-01-01

    The LHCb online system relies on a large and heterogeneous IT infrastructure: it comprises more than 2000 servers and embedded systems and more than 200 network devices. Many of these equipment are critical in order to run the experiment, and it is important to have a monitoring solution efficient enough so that the experts can diagnose and act quickly. While our previous system was based on a central Nagios server, our current system uses a distributed Icinga infrastructure. We have a single instance of Icinga that schedules the checks and deals with the results but we have other servers (called 'workers') to perform the checks. The load induced on the worker is negligible, whereas the central server is fully busy. A client/server model based on Gearman manages queues the clients use to get their tasks and give their results. The other interesting feature of Icinga is the database back-end. Icinga will log the result of every action and check-result in a database. The new installation is now running 36000 service checks on 2100 hosts with 50 Gearman workers. Performances have dramatically improved

  12. The design of distributed database system for HIRFL

    International Nuclear Information System (INIS)

    Wang Hong; Huang Xinmin

    2004-01-01

    This paper is focused on a kind of distributed database system used in HIRFL distributed control system. The database of this distributed database system is established by SQL Server 2000, and its application system adopts the Client/Server model. Visual C ++ is used to develop the applications, and the application uses ODBC to access the database. (authors)

  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. Stability analysis of distributed order fractional chen system.

    Science.gov (United States)

    Aminikhah, H; Refahi Sheikhani, A; Rezazadeh, H

    2013-01-01

    We first investigate sufficient and necessary conditions of stability of nonlinear distributed order fractional system and then we generalize the integer-order Chen system into the distributed order fractional domain. Based on the asymptotic stability theory of nonlinear distributed order fractional systems, the stability of distributed order fractional Chen system is discussed. In addition, we have found that chaos exists in the double fractional order Chen system. Numerical solutions are used to verify the analytical results.

  15. Stability Analysis of Distributed Order Fractional Chen System

    Science.gov (United States)

    Aminikhah, H.; Refahi Sheikhani, A.; Rezazadeh, H.

    2013-01-01

    We first investigate sufficient and necessary conditions of stability of nonlinear distributed order fractional system and then we generalize the integer-order Chen system into the distributed order fractional domain. Based on the asymptotic stability theory of nonlinear distributed order fractional systems, the stability of distributed order fractional Chen system is discussed. In addition, we have found that chaos exists in the double fractional order Chen system. Numerical solutions are used to verify the analytical results. PMID:24489508

  16. Underfrequency Load Shedding for an Islanded Distribution System With Distributed Generators

    DEFF Research Database (Denmark)

    Mahat, Pukar; Chen, Zhe; Bak-Jensen, Birgitte

    2010-01-01

    Significant penetration of distributed generation in many distribution systems has opened an option of operating distribution systems in island mode for economical and technical reasons. However, balancing frequency of the islanded system is still an issue to be solved, especially when the demand...

  17. Clock distribution system for digital computers

    International Nuclear Information System (INIS)

    Loomis, H.H.; Wyman, R.H.

    1981-01-01

    An apparatus is disclosed for eliminating, in each clock distribution amplifier of a clock distribution system, sequential pulse catch-up error due to one pulse ''overtaking'' a prior clock pulse. The apparatus includes timing means to produce a periodic electromagnetic signal with a fundamental frequency having a fundamental frequency component v'01(T); an array of N signal characteristic detector means, with detector means no. 1 receiving the timing means signal and producing a change-of-state signal v1(T) in response to receipt of a signal above a predetermined threshold; N substantially identical filter means, one filter means being operatively associated with each detector means, for receiving the change-of-state signal vn(T) and producing a modified change-of-state signal v'n(T) (N 1, . . . , n) having a fundamental frequency component that is substantially proportional to v'01(T- theta n(T) with a cumulative phase shift theta n(T) having a time derivative that may be made uniformly and arbitrarily small; and with the detector means n+1 (1 < or = n< n) receiving a modified change-of-state signal vn(T) from filter means no. N and, in response to receipt of such a signal above a predetermined threshold, producing a change-of-state signal vn+1

  18. Simulation of warehousing and distribution systems

    Directory of Open Access Journals (Sweden)

    Drago Pupavac

    2005-08-01

    Full Text Available The modern world abounds in simulation models. Thousands of organizations use simulation models to solve business problems. Problems in micro logistics systems are a very important segment of the business problems that can be solved by a simulation method. In most cases logistics simulation models should be developed with a purpose to evaluate the performance of individual value-adding indirect resources of logistics system, their possibilities and operational advantages as well as the flow of logistics entities between the plants, warehouses, and customers. Accordingly, this scientific paper elaborates concisely the theoretical characteristics of simulation models and the domains in which the simulation approach is best suited in logistics. Special attention is paid to simulation modeling of warehousing and distribution subsystems of logistic system and there is an example of spreadsheet application in the function of simulated demand for goods from warehouse. Apart from simulation model induction and deduction methods, the description method and a method of information modeling are applied.

  19. Galileo spacecraft power management and distribution system

    International Nuclear Information System (INIS)

    Detwiler, R.C.; Smith, R.L.

    1990-01-01

    It has been twelve years since two Voyager spacecraft began the direct route to the outer planets. In October 1989 a single Galileo spacecraft started the return to Jupiter. Conceived as a simple Voyager look-alike, the Galileo power management and distribution (PMAD) system has undergone many iterations in configuration. Major changes to the PMAD resulted from dual spun slip ring limitations, variations in launch vehicle thrust capabilities, and launch delays. Lack of an adequate launch vehicle for an interplanetary mission of Galileo's size has resulted in an extremely long flight duration. A Venus-Earth-Earth Gravity Assist (VEEGA) tour, vital to attain the required energy, results in a 6 year trip to Jupiter and its moons. This paper provides a description of the Galileo PMAD and documents the design drivers that established the final as-built hardware

  20. Distributed gas detection system and method

    Science.gov (United States)

    Challener, William Albert; Palit, Sabarni; Karp, Jason Harris; Kasten, Ansas Matthias; Choudhury, Niloy

    2017-11-21

    A distributed gas detection system includes one or more hollow core fibers disposed in different locations, one or more solid core fibers optically coupled with the one or more hollow core fibers and configured to receive light of one or more wavelengths from a light source, and an interrogator device configured to receive at least some of the light propagating through the one or more solid core fibers and the one or more hollow core fibers. The interrogator device is configured to identify a location of a presence of a gas-of-interest by examining absorption of at least one of the wavelengths of the light at least one of the hollow core fibers.

  1. Distributed generation and centralized power system in Thailand

    DEFF Research Database (Denmark)

    Sukkumnoed, Decharut

    2004-01-01

    The paper examines and discusses conflicts between the development of distributed power and centralized power system.......The paper examines and discusses conflicts between the development of distributed power and centralized power system....

  2. Possible mass distributions in the nebulae of other solar systems

    International Nuclear Information System (INIS)

    Brown, W.K.

    1987-01-01

    The supernova shell fragmentation model of solar system formation - previously shown to be successful in describing the mass distribution of our solar system - is used to calculate the mass distributions of other solar nebulae. (Auth.)

  3. Nitrification in Chloraminated Drinking Water Distribution Systems: Factors Affecting Occurrence

    Science.gov (United States)

    Drinking water distribution systems with ammonia present from either naturally occurring ammonia or ammonia addition during chloramination are at risk for nitrification. Nitrification in drinking water distribution systems is undesirable and may result in water quality degradatio...

  4. Distributed adaptive droop control for DC distribution systems

    DEFF Research Database (Denmark)

    Nasirian, Vahidreza; Davoudi, Ali; Lewis, Frank

    2016-01-01

    Summary form only given: A distributed-adaptive droop mechanism is proposed for secondary/primary control of dc microgrids. The conventional secondary control that adjusts the voltage set point for the local droop mechanism is replaced by a voltage regulator. A current regulator is also added...... to fine-tune the droop coefficient for different loading conditions. The voltage regulator uses an observer that processes neighbors' data to estimate the average voltage across the microgrid. This estimation is further used to generate a voltage correction term to adjust the local voltage set point...... with the proposed controller engaged. A low-voltage dc microgrid prototype is used to verify the controller performance, link-failure resiliency, and the plug-and-play capability....

  5. Distributed Adaptive Droop Control for DC Distribution Systems

    DEFF Research Database (Denmark)

    Nasirian, Vahidreza; Davoudi, Ali; Lewis, Frank

    2014-01-01

    A distributed-adaptive droop mechanism is proposed for secondary/primary control of dc Microgrids. The conventional secondary control, that adjusts the voltage set point for the local droop mechanism, is replaced by a voltage regulator. A current regulator is then added to fine-tune the droop...... coefficient for different loading conditions. The voltage regulator uses an observer that processes neighbors’ data to estimate the average voltage across the Microgrid. This estimation is further used to generate a voltage correction term to adjust the local voltage set point. The current regulator compares...... engaged. A low-voltage dc Microgrid prototype is used to verify the controller performance, link-failure resiliency, and the plug-andplay capabilities....

  6. Day-Ahead Congestion Management in Distribution Systems through Household Demand Response and Distribution Congestion Prices

    DEFF Research Database (Denmark)

    Liu, Weijia; Wu, Qiuwei; Wen, Fushuan

    2014-01-01

    into balancing power might challenge the operation of electric distribution systems and cause congestions. This paper presents a distribution congestion price (DCP) based market mechanism to alleviate possible distribution system congestions. By employing the loca- tional marginal pricing (LMP) model...... is proposed. Finally, a practical Danish 60kV/10.5kV distribution system is employed as the test case to verify the proposed method for mitigating congestion....

  7. Cathode power distribution system and method of using the same for power distribution

    Science.gov (United States)

    Williamson, Mark A; Wiedmeyer, Stanley G; Koehl, Eugene R; Bailey, James L; Willit, James L; Barnes, Laurel A; Blaskovitz, Robert J

    2014-11-11

    Embodiments include a cathode power distribution system and/or method of using the same for power distribution. The cathode power distribution system includes a plurality of cathode assemblies. Each cathode assembly of the plurality of cathode assemblies includes a plurality of cathode rods. The system also includes a plurality of bus bars configured to distribute current to each of the plurality of cathode assemblies. The plurality of bus bars include a first bus bar configured to distribute the current to first ends of the plurality of cathode assemblies and a second bus bar configured to distribute the current to second ends of the plurality of cathode assemblies.

  8. Advanced feed water distributing system for WWER 440 steam generators

    Energy Technology Data Exchange (ETDEWEB)

    Matal, O.; Klinga, J. [Energovyzkum Ltd, Brno (Switzerland); Grazl, K. [Vitkovice s.c., Ostrava (Switzerland); Tischler, J.; Mihalik, M. [SEP Atomove Elektrarne Bohunice (Slovakia)

    1995-12-31

    The original designed feed water distributing system was replaced by an advanced one. The characteristics of both feed water distributing systems have been measured and evaluated. The paper deals with the problems of measurement and evaluation of both feed water distributing system characteristics and comparison of statistical data obtained. (orig.). 3 refs.

  9. Advanced feed water distributing system for WWER 440 steam generators

    Energy Technology Data Exchange (ETDEWEB)

    Matal, O; Klinga, J [Energovyzkum Ltd, Brno (Switzerland); Grazl, K [Vitkovice s.c., Ostrava (Switzerland); Tischler, J; Mihalik, M [SEP Atomove Elektrarne Bohunice (Slovakia)

    1996-12-31

    The original designed feed water distributing system was replaced by an advanced one. The characteristics of both feed water distributing systems have been measured and evaluated. The paper deals with the problems of measurement and evaluation of both feed water distributing system characteristics and comparison of statistical data obtained. (orig.). 3 refs.

  10. Deterioration and optimal rehabilitation modelling for urban water distribution systems

    NARCIS (Netherlands)

    Zhou, Y.

    2018-01-01

    Pipe failures in water distribution systems can have a serious impact and hence it’s important to maintain the condition and integrity of the distribution system. This book presents a whole-life cost optimisation model for the rehabilitation of water distribution systems. It combines a pipe breakage

  11. 47 CFR 73.626 - DTV distributed transmission systems.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false DTV distributed transmission systems. 73.626... RADIO BROADCAST SERVICES Television Broadcast Stations § 73.626 DTV distributed transmission systems. (a... distributed transmission system (DTS). Except as expressly provided in this section, DTV stations operating a...

  12. Advanced feed water distributing system for WWER 440 steam generators

    International Nuclear Information System (INIS)

    Matal, O.; Klinga, J.; Grazl, K.; Tischler, J.; Mihalik, M.

    1995-01-01

    The original designed feed water distributing system was replaced by an advanced one. The characteristics of both feed water distributing systems have been measured and evaluated. The paper deals with the problems of measurement and evaluation of both feed water distributing system characteristics and comparison of statistical data obtained. (orig.)

  13. An Architecture for a Wide Area Distributed System

    NARCIS (Netherlands)

    Homburg, P.; Steen, M.R. van; Tanenbaum, A.S.

    1996-01-01

    Distributed systems provide sharing of resources and information over a computer network. A key design issue that makes these systems attractive is that all aspects related to distribution are transparent to users. Unfortunately, general-purpose wide area distributed systems that allow users to

  14. Manganese deposition in drinking water distribution systems.

    Science.gov (United States)

    Gerke, Tammie L; Little, Brenda J; Barry Maynard, J

    2016-01-15

    This study provides a physicochemical assessment of manganese deposits on brass and lead components from two fully operational drinking water distributions systems. One of the systems was maintained with chlorine; the other, with secondary chloramine disinfection. Synchrotron-based in-situ micro X-ray adsorption near edge structure was used to assess the mineralogy. In-situ micro X-ray fluorescence mapping was used to demonstrate the spatial relationships between manganese and potentially toxic adsorbed metal ions. The Mn deposits ranged in thickness from 0.01 to 400 μm. They were composed primarily of Mn oxides/oxhydroxides, birnessite (Mn(3+) and Mn(4+)) and hollandite (Mn(2+) and Mn(4+)), and a Mn silicate, braunite (Mn(2+) and Mn(4+)), in varying proportions. Iron, chromium, and strontium, in addition to the alloying elements lead and copper, were co-located within manganese deposits. With the exception of iron, all are related to specific health issues and are of concern to the U.S. Environmental Protection Agency (U.S. EPA). The specific properties of Mn deposits, i.e., adsorption of metals ions, oxidation of metal ions and resuspension are discussed with respect to their influence on drinking water quality. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. State Electricity Regulatory Policy and Distributed Resources: Distributed Resources and Electric System Reliability

    Energy Technology Data Exchange (ETDEWEB)

    Cowart, R.; Harrington, C.; Moskovitz, D.; Shirley, W.; Weston, F.; Sedano, R.

    2002-10-01

    Designing and implementing credit-based pilot programs for distributed resources distribution is a low-cost, low-risk opportunity to find out how these resources can help defer or avoid costly electric power system (utility grid) distribution upgrades. This report describes implementation options for deaveraged distribution credits and distributed resource development zones. Developing workable programs implementing these policies can dramatically increase the deployment of distributed resources in ways that benefit distributed resource vendors, users, and distribution utilities. This report is one in the State Electricity Regulatory Policy and Distributed Resources series developed under contract to NREL (see Annual Technical Status Report of the Regulatory Assistance Project: September 2000-September 2001, NREL/SR-560-32733). Other titles in this series are: (1) Accommodating Distributed Resources in Wholesale Markets, NREL/SR-560-32497; (2) Distributed Resources and Electric System Re liability, NREL/SR-560-32498; (3) Distribution System Cost Methodologies for Distributed Generation, NREL/SR-560-32500; (4) Distribution System Cost Methodologies for Distributed Generation Appendices, NREL/SR-560-32501.

  16. Transparent checkpointing and process migration in a distributed system

    OpenAIRE

    2004-01-01

    A distributed system for creating a checkpoint for a plurality of processes running on the distributed system. The distributed system includes a plurality of compute nodes with an operating system executing on each compute node. A checkpoint library resides at the user level on each of the compute nodes, and the checkpoint library is transparent to the operating system residing on the same compute node and to the other compute nodes. Each checkpoint library uses a windowed messaging logging p...

  17. Detection of contamination of municipal water distribution systems

    Science.gov (United States)

    Cooper, John F [Oakland, CA

    2012-01-17

    A system for the detection of contaminates of a fluid in a conduit. The conduit is part of a fluid distribution system. A chemical or biological sensor array is connected to the conduit. The sensor array produces an acoustic signal burst in the fluid upon detection of contaminates in the fluid. A supervisory control system connected to the fluid and operatively connected to the fluid distribution system signals the fluid distribution system upon detection of contaminates in the fluid.

  18. Methods and Tools for Profiling and Control of Distributed Systems

    Directory of Open Access Journals (Sweden)

    Sukharev Roman

    2017-01-01

    Full Text Available The article analyzes and standardizes methods for profiling distributed systems that focus on simulation to conduct experiments and build a graph model of the system. The theory of queueing networks is used for simulation modeling of distributed systems, receiving and processing user requests. To automate the above method of profiling distributed systems the software application was developed with a modular structure and similar to a SCADA-system.

  19. Distributed systems for the protection of nuclear stations

    International Nuclear Information System (INIS)

    Jover, P.

    1980-01-01

    The advantages of distributed control systems usually mentioned are improved exploitation, cost reduction, and adaptation to changes in technology. These advantages are obviously very interesting for nuclear power plant applications, and many such systems have been proposed. This note comments on the application of the distributed system concept to protection systems - what should be distributed - and closes with a brief description of a protection system based on microprocessors for pressurized water stations being built in France. (auth) [fr

  20. Energy Efficiency of Distributed Environmental Control Systems

    Energy Technology Data Exchange (ETDEWEB)

    Khalifa, H. Ezzat; Isik, Can; Dannenhoffer, John F. III

    2011-02-23

    In this report, we present an analytical evaluation of the potential of occupant-regulated distributed environmental control systems (DECS) to enhance individual occupant thermal comfort in an office building with no increase, and possibly even a decrease in annual energy consumption. To this end we developed and applied several analytical models that allowed us to optimize comfort and energy consumption in partitioned office buildings equipped with either conventional central HVAC systems or occupant-regulated DECS. Our approach involved the following interrelated components: 1. Development of a simplified lumped-parameter thermal circuit model to compute the annual energy consumption. This was necessitated by the need to perform tens of thousands of optimization calculations involving different US climatic regions, and different occupant thermal preferences of a population of ~50 office occupants. Yearly transient simulations using TRNSYS, a time-dependent building energy modeling program, were run to determine the robustness of the simplified approach against time-dependent simulations. The simplified model predicts yearly energy consumption within approximately 0.6% of an equivalent transient simulation. Simulations of building energy usage were run for a wide variety of climatic regions and control scenarios, including traditional “one-size-fits-all” (OSFA) control; providing a uniform temperature to the entire building, and occupant-selected “have-it-your-way” (HIYW) control with a thermostat at each workstation. The thermal model shows that, un-optimized, DECS would lead to an increase in building energy consumption between 3-16% compared to the conventional approach depending on the climate regional and personal preferences of building occupants. Variations in building shape had little impact in the relative energy usage. 2. Development of a gradient-based optimization method to minimize energy consumption of DECS while keeping each occupant

  1. Fault-tolerant distributed measurement systems

    Energy Technology Data Exchange (ETDEWEB)

    Gater, C.

    1987-01-01

    A 100 kbit/s battery-powered fault-tolerant communications network was developed for use in industrial distributed measurement systems, where a loop controller supervises up to 64 addressable field devices with a network polling period of 250ms. Safety and reliability were optimized using fibre-optic data links and low-power circuitry throughout. Based on a highly redundant loop topology of two receiver/two transmitter communications nodes, the network can tolerate any double node or any quadruple linked failure. Each node circuit is designed to operate continuously for five years using a standard D-type lithium cell, and consists essentially of a CMOS single-chip microcomputer, a specially designed CMOS communications interface chip, some analogue circuity for the optical receivers and transmitters, and interfaces for a sensor/actuator and roving hand-held terminal. The communications interface was implement on a 2436-cell CMOS gate array and feature a self-test facility which provides over 86% fault coverage using only three test vectors. The chip can also be used in the loop controller. Control procedures developed to detect, locate, and reconfigure around faults that occur in the communications network.

  2. Distributed Robust Optimization in Networked System.

    Science.gov (United States)

    Wang, Shengnan; Li, Chunguang

    2016-10-11

    In this paper, we consider a distributed robust optimization (DRO) problem, where multiple agents in a networked system cooperatively minimize a global convex objective function with respect to a global variable under the global constraints. The objective function can be represented by a sum of local objective functions. The global constraints contain some uncertain parameters which are partially known, and can be characterized by some inequality constraints. After problem transformation, we adopt the Lagrangian primal-dual method to solve this problem. We prove that the primal and dual optimal solutions of the problem are restricted in some specific sets, and we give a method to construct these sets. Then, we propose a DRO algorithm to find the primal-dual optimal solutions of the Lagrangian function, which consists of a subgradient step, a projection step, and a diffusion step, and in the projection step of the algorithm, the optimized variables are projected onto the specific sets to guarantee the boundedness of the subgradients. Convergence analysis and numerical simulations verifying the performance of the proposed algorithm are then provided. Further, for nonconvex DRO problem, the corresponding approach and algorithm framework are also provided.

  3. Applied optimal control theory of distributed systems

    CERN Document Server

    Lurie, K A

    1993-01-01

    This book represents an extended and substantially revised version of my earlierbook, Optimal Control in Problems ofMathematical Physics,originally published in Russian in 1975. About 60% of the text has been completely revised and major additions have been included which have produced a practically new text. My aim was to modernize the presentation but also to preserve the original results, some of which are little known to a Western reader. The idea of composites, which is the core of the modern theory of optimization, was initiated in the early seventies. The reader will find here its implementation in the problem of optimal conductivity distribution in an MHD-generatorchannel flow.Sincethen it has emergedinto an extensive theory which is undergoing a continuous development. The book does not pretend to be a textbook, neither does it offer a systematic presentation of the theory. Rather, it reflects a concept which I consider as fundamental in the modern approach to optimization of dis­ tributed systems. ...

  4. Plasma distribution of cathodic ARC deposition system

    International Nuclear Information System (INIS)

    Anders, S.; Raoux, S.; Krishnan, K.; MacGill, R.A.; Brown, I.G.

    1996-01-01

    The plasma distribution using a cathodic arc plasma source with and without magnetic macroparticle filter has been determined by depositing on a transparent plastic substrate and measuring the film absorption. It was found that the width of the distribution depends on the arc current, and it also depends on the cathode material which leads to a spatial separation of the elements when an alloy cathode is used. By applying a magnetic multicusp field near the exit of the magnetic filter, it was possible to modify the plasma distribution and obtain a flat plasma profile with a constant and homogeneous elemental distribution

  5. Simulation-Based Testing of Distributed Systems

    National Research Council Canada - National Science Library

    Rutherford, Matthew J; Carzaniga, Antonio; Wolf, Alexander L

    2006-01-01

    .... Typically written using an imperative programming language, these simulations capture basic algorithmic functionality at the same time as they focus attention on properties critical to distribution...

  6. Parallel and distributed processing: applications to power systems

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Felix; Murphy, Liam [California Univ., Berkeley, CA (United States). Dept. of Electrical Engineering and Computer Sciences

    1994-12-31

    Applications of parallel and distributed processing to power systems problems are still in the early stages. Rapid progress in computing and communications promises a revolutionary increase in the capacity of distributed processing systems. In this paper, the state-of-the art in distributed processing technology and applications is reviewed and future trends are discussed. (author) 14 refs.,1 tab.

  7. OPTIMAL SCHEDULING OF BOOSTER DISINFECTION IN WATER DISTRIBUTION SYSTEMS

    Science.gov (United States)

    Booster disinfection is the addition of disinfectant at locations distributed throughout a water distribution system. Such a strategy can reduce the mass of disinfectant required to maintain a detectable residual at points of consumption in the distribution system, which may lea...

  8. 47 CFR 73.6023 - Distributed transmission systems.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Distributed transmission systems. 73.6023... distributed transmission system. [73 FR 74064, Dec. 5, 2008] ... RADIO BROADCAST SERVICES Class A Television Broadcast Stations § 73.6023 Distributed transmission...

  9. An Intelligent System for Document Retrieval in Distributed Office Environments.

    Science.gov (United States)

    Mukhopadhyay, Uttam; And Others

    1986-01-01

    MINDS (Multiple Intelligent Node Document Servers) is a distributed system of knowledge-based query engines for efficiently retrieving multimedia documents in an office environment of distributed workstations. By learning document distribution patterns and user interests and preferences during system usage, it customizes document retrievals for…

  10. System for forecasting a reactor power distribution

    International Nuclear Information System (INIS)

    Motoda, Hiroshi; Nishizawa, Yasuo.

    1976-01-01

    Purpose: To dispense with frequent running of detector in a BWR type reactor and permit calculation of the prevailing value and forecast value of power distribution in a specified region in an on-line basis. Constitution: The prevailing power distribution P sub(OZ) (where Z indicates a position in the axial direction) at a given position is estimated by prevailing power distribution estimating means, and the average prevailing power distribution Q sub(OZ) in the core is estimated while making correction of a primary neutron distribution model by core average characteristic measuring means. Then, the estimated core average power distribution Q sub(Z) after alteration of the core flow rate or alteration of Xe concentration is estimated by core average power distribution estimating means. At this time, a forecast power distribution P sub(Z) in a specified region after alteration of the flow rate or alteration of the Xe concentration is calculated on the basis of a relation P sub(Z) = (Q sub(Z)/Q sub(OZ)) by using P sub(OZ), Q sub(OZ) and Q sub(Z). The above calculations are carried out in a short period of time by using a process computer. (Ikeda, J.)

  11. Building mail server on distributed computing system

    International Nuclear Information System (INIS)

    Akihiro Shibata; Osamu Hamada; Tomoko Oshikubo; Takashi Sasaki

    2001-01-01

    The electronic mail has become the indispensable function in daily job, and the server stability and performance are required. Using DCE and DFS we have built the distributed electronic mail sever, that is, servers such as SMTP, IMAP are distributed symmetrically, and provides the seamless access

  12. Predictive Analytics for Coordinated Optimization in Distribution Systems

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Rui [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2018-04-13

    This talk will present NREL's work on developing predictive analytics that enables the optimal coordination of all the available resources in distribution systems to achieve the control objectives of system operators. Two projects will be presented. One focuses on developing short-term state forecasting-based optimal voltage regulation in distribution systems; and the other one focuses on actively engaging electricity consumers to benefit distribution system operations.

  13. Response Time Analysis of Distributed Web Systems Using QPNs

    Directory of Open Access Journals (Sweden)

    Tomasz Rak

    2015-01-01

    Full Text Available A performance model is used for studying distributed Web systems. Performance evaluation is done by obtaining load test measurements. Queueing Petri Nets formalism supports modeling and performance analysis of distributed World Wide Web environments. The proposed distributed Web systems modeling and design methodology have been applied in the evaluation of several system architectures under different external loads. Furthermore, performance analysis is done to determine the system response time.

  14. In core system mapping reactor power distribution

    International Nuclear Information System (INIS)

    Yoriyaz, H.; Moreira, J.M.L.

    1989-01-01

    Based on the signals of SPND'S (Self Powered Neutron Detectors) distributed inside of a core, the spatial power distribution is obtained using the MAP program, developed in this work. The methodology applied in MAP program uses a least mean square technique to calculate expansion coefficients that depend on the SPND'S signals. The final power or neutron flux distribution is obtained by a combination of certains functions or expansion modes that are provided from diffusion calculation with the CITATION code. The MAP program is written in PASCAL language and will be used in IEA-R1 reactor for assisting its operation. (author) [pt

  15. Modeling and Control for Islanding Operation of Active Distribution Systems

    DEFF Research Database (Denmark)

    Cha, Seung-Tae; Wu, Qiuwei; Saleem, Arshad

    2011-01-01

    to stabilize the frequency. Different agents are defined to represent different resources in the distribution systems. A test platform with a real time digital simulator (RTDS), an OPen Connectivity (OPC) protocol server and the multi-agent based intelligent controller is established to test the proposed multi......Along with the increasing penetration of distributed generation (DG) in distribution systems, there are more resources for system operators to improve the operation and control of the whole system and enhance the reliability of electricity supply to customers. The distribution systems with DG...... are able to operate in is-landing operation mode intentionally or unintentionally. In order to smooth the transition from grid connected operation to islanding operation for distribution systems with DG, a multi-agent based controller is proposed to utilize different re-sources in the distribution systems...

  16. Analysis of distribution systems with a high penetration of distributed generation

    DEFF Research Database (Denmark)

    Lund, Torsten

    Since the mid eighties, a large number of wind turbines and distributed combined heat and power plants (CHPs) have been connected to the Danish power system. Especially in the Western part, comprising Jutland and Funen, the penetration is high compared to the load demand. In some periods the wind...... power alone can cover the entire load demand. The objective of the work is to investigate the influence of wind power and distributed combined heat and power production on the operation of the distribution systems. Where other projects have focused on the modeling and control of the generators and prime...... movers, the focus of this project is on the operation of an entire distribution system with several wind farms and CHPs. Firstly, the subject of allocation of power system losses in a distribution system with distributed generation is treated. A new approach to loss allocation based on current injections...

  17. Distribution control centers in the Croatian power system with particular consideration on ZAgreb distribution control center

    International Nuclear Information System (INIS)

    Cupin, N.

    2000-01-01

    Discussion about control of Croatian Power system in the view of forthcoming free electricity market did not included do far distribution level. With this article we would like to clarify the role of distribution control centers pointing out importance of Zagreb Distribution control center, with controls one third of Croatian (HEP) consumption. (author)

  18. Asymptotic Likelihood Distribution for Correlated & Constrained Systems

    CERN Document Server

    Agarwal, Ujjwal

    2016-01-01

    It describes my work as summer student at CERN. The report discusses the asymptotic distribution of the likelihood ratio for total no. of parameters being h and 2 out of these being are constrained and correlated.

  19. STANDARDIZED COSTS FOR WATER SUPPLY DISTRIBUTION SYSTEMS

    Science.gov (United States)

    Presented within the report are cost data for construction and operation/maintenance of domestic water distribution and transmission pipelines, domestic water pumping stations, and domestic water storage reservoirs. To allow comparison of new construction with rehabilitation of e...

  20. Versioning System for Distributed Ontology Development

    Science.gov (United States)

    2016-03-15

    Framework for Grid Computing and Semantic Web Services,” Trust Management, Springer Berlin Heidelberg (2004), pp. 16−26. [TIME] W3C, “Time Ontology in...Distributed Ontology Development S.K. Damodaran 15 March 2016 This material is based on work supported by the Assistant Secretary of Defense for...Distributed Ontology Development S.K. Damodaran Formerly Group 59 15 March 2016 Massachusetts Institute of Technology Lincoln Laboratory

  1. Progress on Protection Strategies to Mitigate the Impact of Renewable Distributed Generation on Distribution Systems

    Directory of Open Access Journals (Sweden)

    Mohamad Norshahrani

    2017-11-01

    Full Text Available The benefits of distributed generation (DG based on renewable energy sources leads to its high integration in the distribution network (DN. Despite its well-known benefits, mainly in improving the distribution system reliability and security, there are challenges encountered from a protection system perspective. Traditionally, the design and operation of the protection system are based on a unidirectional power flow in the distribution network. However, the integration of distributed generation causes multidirectional power flows in the system. Therefore, the existing protection systems require some improvement or modification to address this new feature. Various protection strategies for distribution system have been proposed so that the benefits of distributed generation can be fully utilized. This paper reviews the current progress in protection strategies to mitigate the impact of distributed generation in the distribution network. In general, the reviewed strategies in this paper are divided into: (1 conventional protection systems and (2 modifications of the protection systems. A comparative study is presented in terms of the respective benefits, shortcomings and implementation cost. Future directions for research in this area are also presented.

  2. Future development of the electricity systems with distributed generation

    Energy Technology Data Exchange (ETDEWEB)

    Bayod-Rujula, Angel A. [Department of Electrical Engineering, Centro Politecnico Superior, University of Zaragoza, C/Maria de Luna, 3, 50018 Zaragoza (Spain)

    2009-03-15

    Electrical power systems have been traditionally designed taking energy from high-voltage levels, and distributing it to lower voltage level networks. There are large generation units connected to transmission networks. But in the future there will be a large number of small generators connected to the distribution networks. Efficient integration of this distributed generation requires network innovations. A development of active distribution network management, from centralised to more distributed system management, is needed. Information, communication, and control infrastructures will be needed with increasing complexity of system management. Some innovative concepts such as microgrids and virtual utilities will be presented. (author)

  3. Technique of CWM distribution system; CWM ryutsu chukei system gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    Konno, K [Center for Coal Utilization, Japan, Tokyo (Japan); Tanaka, M

    1996-09-01

    It may be intended that CWM is manufactured in areas near coal producing areas in overseas countries and imported as a product requiring lower handling cost than in bulk products. In order to achieve this idea, it is necessary to establish a distribution and relaying system for product transportation inside and outside the country, including relaying bases for receiving, loading and storing the product. This paper reports results of the demonstration tests performed since 1992 to 1996. In the tests, CWM made from Chinese coals was transported from Shijiu Port to the Hibiki relaying base in the city of Kita-Kyushu on 5000 DWT ocean vessels, unloaded, stored, and loaded again on 700 DWT domestic vessels for distribution to users. Since the inauguration of transportations, 40,000 tons of CWM were delivered yearly to the Okayama plant of Tayca Company, and about 20,000 tons to the Mizushima power plant of the Chubu Electric Power Company over a period from 1995 to 1996. During the period, a number of findings were acquired in different aspects, including quality control of incoming and outgoing CWM, stability in quantity and properties, loading and unloading works, and transportation. Although reduction in subsidence during transportation and storage was indicated desirable, the practical applicability was verified for the relaying system as a whole. 4 refs., 15 figs., 3 tabs.

  4. A Heuristic Approach to Distributed Generation Source Allocation for Electrical Power Distribution Systems

    Directory of Open Access Journals (Sweden)

    M. Sharma

    2010-12-01

    Full Text Available The recent trends in electrical power distribution system operation and management are aimed at improving system conditions in order to render good service to the customer. The reforms in distribution sector have given major scope for employment of distributed generation (DG resources which will boost the system performance. This paper proposes a heuristic technique for allocation of distribution generation source in a distribution system. The allocation is determined based on overall improvement in network performance parameters like reduction in system losses, improvement in voltage stability, improvement in voltage profile. The proposed Network Performance Enhancement Index (NPEI along with the heuristic rules facilitate determination of feasible location and corresponding capacity of DG source. The developed approach is tested with different test systems to ascertain its effectiveness.

  5. Distributed expert systems for ground and space applications

    Science.gov (United States)

    Buckley, Brian; Wheatcraft, Louis

    1992-01-01

    Presented here is the Spacecraft Command Language (SCL) concept of the unification of ground and space operations using a distributed approach. SCL is a hybrid software environment borrowing from expert system technology, fifth generation language development, and multitasking operating system environments. Examples of potential uses for the system and current distributed applications of SCL are given.

  6. Understanding and Improving the Performance Consistency of Distributed Computing Systems

    NARCIS (Netherlands)

    Yigitbasi, M.N.

    2012-01-01

    With the increasing adoption of distributed systems in both academia and industry, and with the increasing computational and storage requirements of distributed applications, users inevitably demand more from these systems. Moreover, users also depend on these systems for latency and throughput

  7. A Simple Adaptive Overcurrent Protection of Distribution Systems With Distributed Generation

    DEFF Research Database (Denmark)

    Mahat, Pukar; Chen, Zhe; Bak-Jensen, Birgitte

    2011-01-01

    current when the system is connected to the grid and when it is islanded. This paper proposes the use of adaptive protection, using local information, to overcome the challenges of the overcurrent protection in distribution systems with distributed generation. The trip characteristics of the relays...... are updated by detecting operating states (grid connected or island) and the faulted section. The paper also proposes faulted section detection using the time over-current characteristics of the protective relays. Simulation results show that the operating state and faulted section can be correctly identified......A significant increase in the penetration of distributed generation has resulted in a possibility of operating distribution systems with distributed generation in islanded mode. However, over-current protection of an islanded distribution system is still an issue due to the difference in fault...

  8. Reliability Evaluation of Distribution System Considering Sequential Characteristics of Distributed Generation

    Directory of Open Access Journals (Sweden)

    Sheng Wanxing

    2016-01-01

    Full Text Available In allusion to the randomness of output power of distributed generation (DG, a reliability evaluation model based on sequential Monte Carlo simulation (SMCS for distribution system with DG is proposed. Operating states of the distribution system can be sampled by SMCS in chronological order thus the corresponding output power of DG can be generated. The proposed method has been tested on feeder F4 of IEEE-RBTS Bus 6. The results show that reliability evaluation of distribution system considering the uncertainty of output power of DG can be effectively implemented by SMCS.

  9. 2015 Plan. Project 6: urban and rural distribution systems

    International Nuclear Information System (INIS)

    1993-06-01

    The main development trends of distribution systems in 2015 Plan is studied, with the data of market continuity, costs and evolution of the physique system. Some factors that will influence the evolution of the distribution systems are presented and the impacts of economic view are discussed. The strategic lines that will give direction for the distribution expansion, including the energy conservation are also shown. (C.G.C.)

  10. Distributed Impact Detector System (DIDS) Health Monitoring System Evaluation

    Science.gov (United States)

    Prosser, William H.; Madaras, Eric I.

    2010-01-01

    Damage due to impacts from micrometeoroids and orbital debris is one of the most significant on-orbit hazards for spacecraft. Impacts to thermal protection systems must be detected and the damage evaluated to determine if repairs are needed to allow safe re-entry. To address this issue for the International Space Station Program, Langley Research Center and Johnson Space Center technologists have been working to develop and implement advanced methods for detecting impacts and resultant leaks. LaRC funded a Small Business Innovative Research contract to Invocon, Inc. to develop special wireless sensor systems that are compact, light weight, and have long battery lifetimes to enable applications to long duration space structures. These sensor systems are known as distributed impact detection systems (DIDS). In an assessment, the NASA Engineering and Safety Center procured two prototype DIDS sensor units to evaluate their capabilities in laboratory testing and field testing in an ISS Node 1 structural test article. This document contains the findings of the assessment.

  11. Dynamic models for transient stability analysis of transmission and distribution systems with distributed generation : an overview

    NARCIS (Netherlands)

    Boemer, J.C.; Gibescu, M.; Kling, W.L.

    2009-01-01

    Distributed Generation is increasing in nowadays power systems. Small scale systems such as photovoltaic, biomass or small cogeneration plants are connected to the distribution level, while large wind farms will be connected to the transmission level. Both trends lead to a replacement of large

  12. Drinking water distribution systems: assessing and reducing risks

    National Research Council Canada - National Science Library

    Committee on Public Water Supply Distribution Systems: Assessing and Reducing Risks, National Research Council

    2006-01-01

    .... Distribution systems -- consisting of pipes, pumps, valves, storage tanks, reservoirs, meters, fittings, and other hydraulic appurtenances -- carry drinking water from a centralized treatment plant...

  13. Adaptive Distributed Intelligent Control Architecture for Future Propulsion Systems (Preprint)

    National Research Council Canada - National Science Library

    Behbahani, Alireza R

    2007-01-01

    .... Distributed control is potentially an enabling technology for advanced intelligent propulsion system concepts and is one of the few control approaches that is able to provide improved component...

  14. Distributed Computations Environment Protection Using Artificial Immune Systems

    Directory of Open Access Journals (Sweden)

    A. V. Moiseev

    2011-12-01

    Full Text Available In this article the authors describe possibility of artificial immune systems applying for distributed computations environment protection from definite types of malicious impacts.

  15. Web Based Distributed Coastal Image Analysis System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This project develops Web based distributed image analysis system processing the Moderate Resolution Imaging Spectroradiometer (MODIS) data to provide decision...

  16. Hybrid control of the distributed refrigeration system

    DEFF Research Database (Denmark)

    Chen, L.; Wisniewski, R.

    2010-01-01

    consumption. The paper focuses on synchronization dynamics of the refrigeration system modeled as a piecewise-affine switched system. System behaviors are analyzed using chaos theory. The synchronization phenomenon is interpreted as a stable low-period orbit; if the system has a high-order periodic orbit...

  17. Intelligent distributed voltage control system for smart grid application

    Energy Technology Data Exchange (ETDEWEB)

    Sajadi, Amirhossein [Warsaw Univ. of Technology (Poland); Ariatabar, Mitra [RWTH Aachen Univ. (Germany)

    2012-07-01

    Increasing penetration of the renewable energy source (RES) units in distribution networks particularly due to nonlinear and unpredictable nature of renewable units brings up new challenges in different aspects of electricity network, which leads to more complex power systems. Multi-agent system is consisting of agents which are capable to perceive environment that they are located in and to reacts with each other by communication infrastructure in order to achieve overall goals. In this paper an approach to control the voltage based on in the power distribution system is proposed and discussed. Therefore, a multi-agent system has been integrated with artificial intelligence to come up with fuzzy multi-agent based system. The proposed control scheme is deployed to a smart distribution system consisting distribution generation units, modelled in MATLAB/Simulink, to evaluate its effectiveness. The simulation results show how proposed system can regulate voltage in smart distribution feeders. (orig.)

  18. Coordinated Optimization of Distributed Energy Resources and Smart Loads in Distribution Systems: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Rui; Zhang, Yingchen

    2016-08-01

    Distributed energy resources (DERs) and smart loads have the potential to provide flexibility to the distribution system operation. A coordinated optimization approach is proposed in this paper to actively manage DERs and smart loads in distribution systems to achieve the optimal operation status. A three-phase unbalanced Optimal Power Flow (OPF) problem is developed to determine the output from DERs and smart loads with respect to the system operator's control objective. This paper focuses on coordinating PV systems and smart loads to improve the overall voltage profile in distribution systems. Simulations have been carried out in a 12-bus distribution feeder and results illustrate the superior control performance of the proposed approach.

  19. Electrical power systems for distributed generation

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, T.A.; Huval, S.J. [Stewart & Stevenson Services, Inc., Houston, TX (United States)

    1996-12-31

    {open_quotes}Distributed Generation{close_quotes} has become the {open_quotes}buzz{close_quotes} word of an electric utility industry facing deregulation. Many industrial facilities utilize equipment in distributed installations to serve the needs of a thermal host through the capture of exhaust energy in a heat recovery steam generator. The electrical power generated is then sold as a {open_quotes}side benefit{close_quotes} to the cost-effective supply of high quality thermal energy. Distributed generation is desirable for many different reasons, each with unique characteristics of the product. Many years of experience in the distributed generation market has helped Stewart & Stevenson to define a range of product features that are crucial to most any application. The following paper will highlight a few of these applications. The paper will also examine the range of products currently available and in development. Finally, we will survey the additional services offered by Stewart & Stevenson to meet the needs of a rapidly changing power generation industry.

  20. Managing Distributed Systems with Smart Subscriptions

    Science.gov (United States)

    Filman, Robert E.; Lee, Diana D.; Swanson, Keith (Technical Monitor)

    2000-01-01

    We describe an event-based, publish-and-subscribe mechanism based on using 'smart subscriptions' to recognize weakly-structured events. We present a hierarchy of subscription languages (propositional, predicate, temporal and agent) and algorithms for efficiently recognizing event matches. This mechanism has been applied to the management of distributed applications.

  1. Velocity distributions in dilute granular systems

    NARCIS (Netherlands)

    van Zon, J.S.; Mac Kintosh, F.C.

    2005-01-01

    We investigate the idea that velocity distributions in granular gases are determined mainly by η, the coefficient of restitution and q, which measures the relative importance of heating (or energy input) to collisions. To this end, we study by numerical simulation the properties of inelastic gases

  2. Self Configurable Intelligent Distributed Antenna System

    DEFF Research Database (Denmark)

    Kumar, Ambuj; Mihovska, Albena Dimitrova; Prasad, Ramjee

    2016-01-01

    with their respective base stations, spectrum pooling and management at antenna end is not efficient. The situation worsens in Heterogeneous and Dense-net conditions in an Area of Interest (AoI). In this paper, we propose a DAS based intelligent architecture referred to as Self Configurable Intelligent Distributed...

  3. Heartbeat-based error diagnosis framework for distributed embedded systems

    Science.gov (United States)

    Mishra, Swagat; Khilar, Pabitra Mohan

    2012-01-01

    Distributed Embedded Systems have significant applications in automobile industry as steer-by-wire, fly-by-wire and brake-by-wire systems. In this paper, we provide a general framework for fault detection in a distributed embedded real time system. We use heartbeat monitoring, check pointing and model based redundancy to design a scalable framework that takes care of task scheduling, temperature control and diagnosis of faulty nodes in a distributed embedded system. This helps in diagnosis and shutting down of faulty actuators before the system becomes unsafe. The framework is designed and tested using a new simulation model consisting of virtual nodes working on a message passing system.

  4. Communication infrastructure and data management for operating smart distribution systems

    NARCIS (Netherlands)

    Brunner, C.; Buchholz, B.M.; Gelfand, A.; Kamphuis, I.G.; Naumann, A.

    2012-01-01

    The enhancement of distribution networks into smart grids is based on three pillars: • Energy management on distribution level, • Distribution system automation, • Involvement of the consumers into the market for electricity by smart metering All these functions require an intensive exchange of

  5. Prototyping a Distributed Information Retrieval System That Uses Statistical Ranking.

    Science.gov (United States)

    Harman, Donna; And Others

    1991-01-01

    Built using a distributed architecture, this prototype distributed information retrieval system uses statistical ranking techniques to provide better service to the end user. Distributed architecture was shown to be a feasible alternative to centralized or CD-ROM information retrieval, and user testing of the ranking methodology showed both…

  6. Island Partition of Distribution System with Distributed Generators Considering Protection of Vulnerable Nodes

    Directory of Open Access Journals (Sweden)

    Gang Xu

    2017-10-01

    Full Text Available To improve the reliability of power supply in the case of the fault of distribution system with multiple distributed generators (DGs and reduce the influence of node voltage fluctuation on the stability of distribution system operation in power restoration, this paper proposes an island partition strategy of the distribution system considering the protection of vulnerable nodes. First of all, the electrical coupling coefficient of neighboring nodes is put forward according to distribution system topology and equivalent electrical impedance, and the power-dependence relationship between neighboring nodes is calculated based on the direction and level of the power flow between nodes. Then, the bidirectional transmission of the coupling features of neighboring nodes is realized through the modified PageRank algorithm, thus identifying the vulnerable nodes that have a large influence on the stability of distribution system operation. Next, combining the index of node vulnerability, an island partition model is constructed with the restoration of important loads as the primary goal. In addition, the mutually exclusive firefly algorithm (MEFA is also proposed to realize the interaction of learning and competition among fireflies, thus enhancing the globally optimal solution search ability of the algorithm proposed. The proposed island partition method is verified with a Pacific Gas and Electric Company (PG and E 60-node test system. Comparison with other methods demonstrates that the new method is feasible for the distribution system with multiple types of distributed generations and valid to enhance the stability and safety of the grid with a relatively power restoration ratio.

  7. An improved AVC strategy applied in distributed wind power system

    Science.gov (United States)

    Zhao, Y. N.; Liu, Q. H.; Song, S. Y.; Mao, W.

    2016-08-01

    Traditional AVC strategy is mainly used in wind farm and only concerns about grid connection point, which is not suitable for distributed wind power system. Therefore, this paper comes up with an improved AVC strategy applied in distributed wind power system. The strategy takes all nodes of distribution network into consideration and chooses the node having the most serious voltage deviation as control point to calculate the reactive power reference. In addition, distribution principles can be divided into two conditions: when wind generators access to network on single node, the reactive power reference is distributed according to reactive power capacity; when wind generators access to network on multi-node, the reference is distributed according to sensitivity. Simulation results show the correctness and reliability of the strategy. Compared with traditional control strategy, the strategy described in this paper can make full use of generators reactive power output ability according to the distribution network voltage condition and improve the distribution network voltage level effectively.

  8. Operating-System Support for Distributed Multimedia

    NARCIS (Netherlands)

    Mullender, Sape J.; Leslie, Ian M.; McAuley, Derek

    1994-01-01

    Multimedia applications place new demands upon processors, networks and operating systems. While some network designers, through ATM for example, have considered revolutionary approaches to supporting multimedia, the same cannot be said for operating systems designers. Most work is evolutionary in

  9. Distributed redundancy and robustness in complex systems

    KAUST Repository

    Randles, Martin; Lamb, David J.; Odat, Enas M.; Taleb-Bendiab, Azzelarabe

    2011-01-01

    that emerges in complex biological and natural systems. However, in order to promote an evolutionary approach, through emergent self-organisation, it is necessary to specify the systems in an 'open-ended' manner where not all states of the system are prescribed

  10. Multichannel system for angular distribution measurements

    International Nuclear Information System (INIS)

    Burjan, V.; Kroha, V.; Putz, K.

    A description is given of the individual blocks of the spectrometric apparatus used for measuring the angular distribution of particle spectra and excitation functions of (d,p) reactions at an electrostatic accelerator and the U-120 M cyclotron, both operating at the Nuclear Physics Institute of the Czechoslovak Academy of Sciences at Rez. Main attention was devoted to attaining maximum energy resolution at a high measurement efficiency, this by installing 8 independent spectrometric chains allowing simultaneous measurement of angular distribution in 8 points of the beam. The semiconductor detectors were cooled to -40 degC to -60 degC, which significantly reduced the level of inherent detector noise. An energy resolution of 13 keV was attained using Tesla detectors at a particle energy of 11 MeV. A brief review of data processing and software is given. (B.S.)

  11. Distributed Space Missions for Earth System Monitoring

    CERN Document Server

    2013-01-01

    A key addition to Springer's Space Technology Library series, this edited volume features the work of dozens of authors and offers a wealth of perspectives on distributed Earth observation missions. In sum, it is an eloquent synthesis of the fullest possible range of current approaches to a fast-developing field characterized by growing membership of the 'space club' to include nations formerly regarded as part of the Third World. The volume's four discrete sections focus on the topic's various aspects, including the key theoretical and technical issues arising from the division of payloads onto different satellites. The first is devoted to analyzing distributed synthetic aperture radars, with bi- and multi-static radars receiving separate treatment. This is followed by a full discussion of relative dynamics, guidance, navigation and control. Here, the separate topics of design; establishment, maintenance and control; and measurements are developed with relative trajectory as a reference point, while the dis...

  12. LPV Identification of a Heat Distribution System

    DEFF Research Database (Denmark)

    Trangbæk, K; Bendtsen, Jan Dimon

    2010-01-01

    This paper deals with incremental system identification of district heating systems to improve control performance. As long as various parameters, e.g. valve settings, are kept fixed, the dynamics of district heating systems can be approximated well by linear models; however, the dynamics change ....... The approach is tested on a laboratory setup emulating a district heating system, where local controllers regulate pumps connected to a common supply. Experiments show that cross-couplings in the system can indeed be identified in closed-loop operation....

  13. Architectural transformations in network services and distributed systems

    CERN Document Server

    Luntovskyy, Andriy

    2017-01-01

    With the given work we decided to help not only the readers but ourselves, as the professionals who actively involved in the networking branch, with understanding the trends that have developed in recent two decades in distributed systems and networks. Important architecture transformations of distributed systems have been examined. The examples of new architectural solutions are discussed. Content Periodization of service development Energy efficiency Architectural transformations in Distributed Systems Clustering and Parallel Computing, performance models Cloud Computing, RAICs, Virtualization, SDN Smart Grid, Internet of Things, Fog Computing Mobile Communication from LTE to 5G, DIDO, SAT-based systems Data Security Guaranteeing Distributed Systems Target Groups Students in EE and IT of universities and (dual) technical high schools Graduated engineers as well as teaching staff About the Authors Andriy Luntovskyy provides classes on networks, mobile communication, software technology, distributed systems, ...

  14. The distribution of wind power forecast errors from operational systems

    Energy Technology Data Exchange (ETDEWEB)

    Hodge, Bri-Mathias; Ela, Erik; Milligan, Michael

    2011-07-01

    Wind power forecasting is one important tool in the integration of large amounts of renewable generation into the electricity system. Wind power forecasts from operational systems are not perfect, and thus, an understanding of the forecast error distributions can be important in system operations. In this work, we examine the errors from operational wind power forecasting systems, both for a single wind plant and for an entire interconnection. The resulting error distributions are compared with the normal distribution and the distribution obtained from the persistence forecasting model at multiple timescales. A model distribution is fit to the operational system forecast errors and the potential impact on system operations highlighted through the generation of forecast confidence intervals. (orig.)

  15. Decentralized Resource Management in Distributed Computer Systems.

    Science.gov (United States)

    1982-02-01

    directly exchanging user state information. Eventcounts and sequencers correspond to semaphores in the sense that synchronization primitives are used to...and techniques are required to achieve synchronization in distributed computers without reliance on any centralized entity such as a semaphore ...known solutions to the access synchronization problem was Dijkstra’s semaphore [12]. The importance of the semaphore is that it correctly addresses the

  16. FIPA agent based network distributed control system

    Energy Technology Data Exchange (ETDEWEB)

    D. Abbott; V. Gyurjyan; G. Heyes; E. Jastrzembski; C. Timmer; E. Wolin

    2003-03-01

    A control system with the capabilities to combine heterogeneous control systems or processes into a uniform homogeneous environment is discussed. This dynamically extensible system is an example of the software system at the agent level of abstraction. This level of abstraction considers agents as atomic entities that communicate to implement the functionality of the control system. Agents' engineering aspects are addressed by adopting the domain independent software standard, formulated by FIPA. Jade core Java classes are used as a FIPA specification implementation. A special, lightweight, XML RDFS based, control oriented, ontology markup language is developed to standardize the description of the arbitrary control system data processor. Control processes, described in this language, are integrated into the global system at runtime, without actual programming. Fault tolerance and recovery issues are also addressed.

  17. FIPA agent based network distributed control system

    International Nuclear Information System (INIS)

    Abbott, D.; Gyurjyan, V.; Heyes, G.; Jastrzembski, E.; Timmer, C.; Wolin, E.

    2003-01-01

    A control system with the capabilities to combine heterogeneous control systems or processes into a uniform homogeneous environment is discussed. This dynamically extensible system is an example of the software system at the agent level of abstraction. This level of abstraction considers agents as atomic entities that communicate to implement the functionality of the control system. Agents' engineering aspects are addressed by adopting the domain independent software standard, formulated by FIPA. Jade core Java classes are used as a FIPA specification implementation. A special, lightweight, XML RDFS based, control oriented, ontology markup language is developed to standardize the description of the arbitrary control system data processor. Control processes, described in this language, are integrated into the global system at runtime, without actual programming. Fault tolerance and recovery issues are also addressed

  18. Research on intelligent power distribution system for spacecraft

    Science.gov (United States)

    Xia, Xiaodong; Wu, Jianju

    2017-10-01

    The power distribution system (PDS) mainly realizes the power distribution and management of the electrical load of the whole spacecraft, which is directly related to the success or failure of the mission, and hence is an important part of the spacecraft. In order to improve the reliability and intelligent degree of the PDS, and considering the function and composition of spacecraft power distribution system, this paper systematically expounds the design principle and method of the intelligent power distribution system based on SSPC, and provides the analysis and verification of the test data additionally.

  19. The frequency characteristics of medium voltage distribution system impedances

    Directory of Open Access Journals (Sweden)

    Liviu Emil Petrean

    2009-10-01

    Full Text Available In this paper we present the frequency characteristics of impedances involved in the electrical equivalent circuit of a large medium voltage distribution system. These impedances influence harmonics distortions propagation occurring due to the nonsinusoidal loads. We analyse the case of a 10 kV large urban distribution system which supplies industrial, commercial and residential customers. The influence of various parameters of the distribution network on the frequency characteristics are presented, in order to assess the interaction of harmonic distortion and distribution system network.

  20. Power Quality in DC Power Distribution Systems and Microgrids

    Directory of Open Access Journals (Sweden)

    Stephen Whaite

    2015-05-01

    Full Text Available This review paper discusses power quality considerations for direct current (DC electric power distribution systems, particularly DC microgrids. First, four selected sample DC architectures are discussed to provide motivation for the consideration of power quality in DC systems. Second, a brief overview of power quality challenges in conventional alternating current (AC distribution systems is given to establish the field of power quality. Finally, a survey of literature addressing power quality issues in DC systems is presented, and necessary power quality considerations in DC distribution system design and operation are discussed.

  1. Distributed Rocket Engine Testing Health Monitoring System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The on-ground and Distributed Rocket Engine Testing Health Monitoring System (DiRETHMS) provides a system architecture and software tools for performing diagnostics...

  2. Distributed Rocket Engine Testing Health Monitoring System, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Leveraging the Phase I achievements of the Distributed Rocket Engine Testing Health Monitoring System (DiRETHMS) including its software toolsets and system building...

  3. Distributed Space System Technology Demonstrations with the Emerald Nanosatellite

    Science.gov (United States)

    Twiggs, Robert

    2002-01-01

    A viewgraph presentation of Distributed Space System Technologies utilizing the Emerald Nanosatellite is shown. The topics include: 1) Structure Assembly; 2) Emerald Mission; 3) Payload and Mission Operations; 4) System and Subsystem Description; and 5) Safety Integration and Testing.

  4. Agent-based distributed hierarchical control of dc microgrid systems

    DEFF Research Database (Denmark)

    Meng, Lexuan; Vasquez, Juan Carlos; Guerrero, Josep M.

    2014-01-01

    In order to enable distributed control and management for microgrids, this paper explores the application of information consensus and local decisionmaking methods formulating an agent based distributed hierarchical control system. A droop controlled paralleled DC/DC converter system is taken as ....... Standard genetic algorithm is applied in each local control system in order to search for a global optimum. Hardware-in-Loop simulation results are shown to demonstrate the effectiveness of the method.......In order to enable distributed control and management for microgrids, this paper explores the application of information consensus and local decisionmaking methods formulating an agent based distributed hierarchical control system. A droop controlled paralleled DC/DC converter system is taken...... as a case study. The objective is to enhance the system efficiency by finding the optimal sharing ratio of load current. Virtual resistances in local control systems are taken as decision variables. Consensus algorithms are applied for global information discovery and local control systems coordination...

  5. Nitrification in Chloraminated Drinking Water Distribution Systems - Occurrence

    Science.gov (United States)

    This chapter discusses available information on nitrification occurrence in drinking water chloraminated distribution systems. Chapter 4 provides an introduction to causes and controls for nitrification in chloraminated drinking water systems. Both chapters are intended to serve ...

  6. A generalization information management system applied to electrical distribution

    Energy Technology Data Exchange (ETDEWEB)

    Geisler, K.I.; Neumann, S.A.; Nielsen, T.D.; Bower, P.K. (Empros Systems International (US)); Hughes, B.A.

    1990-07-01

    This article presents a system solution approach that meets the requirements being imposed by industry trends and the electric utility customer. Specifically, the solution addresses electric distribution management systems. Electrical distribution management is a particularly well suited area of application because it involves a high diversity of tasks, which are currently supported by a proliferation of automated islands. Islands of automation which currently exist include (among others) distribution operations, load management, automated mapping, facility management, work order processing, and planning.

  7. Architectural notes: a framework for distributed systems development

    NARCIS (Netherlands)

    Pires, L.F.; Ferreira Pires, Luis

    1994-01-01

    This thesis develops a framework of methods and techniques for distributed systems development. This framework consists of two related domains in which design concepts for distributed systems are defined: the entity domain and the behaviour domain. In the entity domain we consider structures of

  8. EBO feed water distribution system, experience gained from operation

    Energy Technology Data Exchange (ETDEWEB)

    Matal, O. [Energovyzkum, Brno (Switzerland); Schmidt, S.; Mihalik, M. [Atomove Elektrarne Bohunice, Jaslovske Bohunice (Switzerland)

    1997-12-31

    Advanced feed water distribution systems of the EBO design have been installed into steam generators at Units 3 and 4 of the NPP Jaslovske Bohunice (VVER 440). Experiences gained from the operation of steam generators with the advanced feed water distribution systems are discussed in the paper. (orig.). 4 refs.

  9. Distribution function of excitations in systems with fractional statistics

    International Nuclear Information System (INIS)

    Protogenov, A.P.

    1992-08-01

    The distribution function of low-energy excitations in 2+1D systems has been considered. It is shown that in these systems the quantum distribution function differs from the usual one by having a finite value of the entropy of linked braids. (author). 47 refs

  10. A Modeling Framework for Schedulability Analysis of Distributed Avionics Systems

    DEFF Research Database (Denmark)

    Han, Pujie; Zhai, Zhengjun; Nielsen, Brian

    2018-01-01

    This paper presents a modeling framework for schedulability analysis of distributed integrated modular avionics (DIMA) systems that consist of spatially distributed ARINC-653 modules connected by a unified AFDX network. We model a DIMA system as a set of stopwatch automata (SWA) in UPPAAL...

  11. Ring interconnection for distributed memory automation and computing system

    Energy Technology Data Exchange (ETDEWEB)

    Vinogradov, V I [Inst. for Nuclear Research of the Russian Academy of Sciences, Moscow (Russian Federation)

    1996-12-31

    Problems of development of measurement, acquisition and central systems based on a distributed memory and a ring interface are discussed. It has been found that the RAM LINK-type protocol can be used for ringlet links in non-symmetrical distributed memory architecture multiprocessor system interaction. 5 refs.

  12. Particulate fingerprinting of water quality in the distribution system ...

    African Journals Online (AJOL)

    Particles in the distribution system play an important role in the perception? Not clear what is meant) of drinking water quality, particularly in association with discolouration. In The Netherlands the water quality in the distribution system is traditionally monitored by turbidity measurements. However, turbidity is hard to quantify ...

  13. Protection issues on microgrid/distributed generation based systems

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Angelo R. [Centro Federal de Educacao Tecnologica de Minas Gerais (CEFET-MG), Belo Horizonte, MG (Brazil); Ribeiro, Paulo F. [Calvin College, Grand Rapids, MI (United States). Dept. of Electrical Engineering; Iung, Anderson M. [Geracao Paranapanema S.A., SP (Brazil). Duke Energy International. Market Analysis Dept.; Garcia, Paulo A.N. [Federal University of Juiz de Fora (UFJF), MG (Brazil). Dept. of Circuits

    2009-07-01

    This paper aims to discuss protection issues related to the presence of distributed generation (DG) in distribution systems. A case study is developed to show some impacts of transitions and operations with relay static settings to verify the reliability of systems in the presence of DG. (author)

  14. GROWTH OF HETROTROPHIC BIOFILMS IN A WATER DISTRIBUTION SYSTEM SIMULATOR

    Science.gov (United States)

    The U.S. EPA has designed and constructed a distribution system simulator (DSS) to evaluate factors which influence water quality within water distribution systems. Six individual 25 meter lengths of 15 cm diameter ductile iron pipe are arranged into loop configurations. Each lo...

  15. EBO feed water distribution system, experience gained from operation

    Energy Technology Data Exchange (ETDEWEB)

    Matal, O [Energovyzkum, Brno (Switzerland); Schmidt, S; Mihalik, M [Atomove Elektrarne Bohunice, Jaslovske Bohunice (Switzerland)

    1998-12-31

    Advanced feed water distribution systems of the EBO design have been installed into steam generators at Units 3 and 4 of the NPP Jaslovske Bohunice (VVER 440). Experiences gained from the operation of steam generators with the advanced feed water distribution systems are discussed in the paper. (orig.). 4 refs.

  16. An Applet-based Anonymous Distributed Computing System.

    Science.gov (United States)

    Finkel, David; Wills, Craig E.; Ciaraldi, Michael J.; Amorin, Kevin; Covati, Adam; Lee, Michael

    2001-01-01

    Defines anonymous distributed computing systems and focuses on the specifics of a Java, applet-based approach for large-scale, anonymous, distributed computing on the Internet. Explains the possibility of a large number of computers participating in a single computation and describes a test of the functionality of the system. (Author/LRW)

  17. Battery management system with distributed wireless sensors

    Science.gov (United States)

    Farmer, Joseph C.; Bandhauer, Todd M.

    2016-02-23

    A system for monitoring parameters of an energy storage system having a multiplicity of individual energy storage cells. A radio frequency identification and sensor unit is connected to each of the individual energy storage cells. The radio frequency identification and sensor unit operates to sense the parameter of each individual energy storage cell and provides radio frequency transmission of the parameters of each individual energy storage cell. A management system monitors the radio frequency transmissions from the radio frequency identification and sensor units for monitoring the parameters of the energy storage system.

  18. Economic optimization in new distribution system construction

    International Nuclear Information System (INIS)

    Freese, J.

    1994-01-01

    The substantial capital investment and the long-term nature of extension projects make it necessary, in particular for local utilities, to intensively prepare their construction projects. Resulting from this context, the PC-program MAFIOSY for calculating and optimizing the economics of pipeline extension projects has been developed to facilitate the decision-making process and to ensure an optimum decision. The optimum structure of a distribution network to be designed for a new service area is defined using the four-phase method set out below: Situation Audit; Determination of Potential; Determination of Economic and Technical Parameters; Optimization. (orig.)

  19. Distributed Power-Generation Systems and Protection

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Yang, Yongheng; Yang, Dongsheng

    2017-01-01

    the challenging issues and, more importantly, to leverage the energy generation, stringent demands from both utility operators and consumers have been imposed on the DPGS. Furthermore, as the core of energy conversion, numerous power electronic converters employing advanced control techniques have been developed...... for the DPGS to consolidate the integration. In light of the above, this paper reviews the power-conversion and control technologies used for DPGSs. The impacts of the DPGS on the distributed grid are also examined, and more importantly, strategies for enhancing the connection and protection of the DPGS...

  20. 11th International Symposium on Distributed Autonomous Robotic Systems

    CERN Document Server

    Chirikjian, Gregory

    2014-01-01

    Distributed robotics is a rapidly growing and maturing interdisciplinary research area lying at the intersection of computer science, network science, control theory, and electrical and mechanical engineering. The goal of the Symposium on Distributed Autonomous Robotic Systems (DARS) is to exchange and stimulate research ideas to realize advanced distributed robotic systems. This volume of proceedings includes 31 original contributions presented at the 2012 International Symposium on Distributed Autonomous Robotic Systems (DARS 2012) held in November 2012 at the Johns Hopkins University in Baltimore, MD USA. The selected papers in this volume are authored by leading researchers from Asia, Europa, and the Americas, thereby providing a broad coverage and perspective of the state-of-the-art technologies, algorithms, system architectures, and applications in distributed robotic systems. The book is organized into five parts, representative of critical long-term and emerging research thrusts in the multi-robot com...

  1. Electric Power Distribution System Model Simplification Using Segment Substitution

    Energy Technology Data Exchange (ETDEWEB)

    Reiman, Andrew P.; McDermott, Thomas E.; Akcakaya, Murat; Reed, Gregory F.

    2018-05-01

    Quasi-static time-series (QSTS) simulation is used to simulate the behavior of distribution systems over long periods of time (typically hours to years). The technique involves repeatedly solving the load-flow problem for a distribution system model and is useful for distributed energy resource (DER) planning. When a QSTS simulation has a small time step and a long duration, the computational burden of the simulation can be a barrier to integration into utility workflows. One way to relieve the computational burden is to simplify the system model. The segment substitution method of simplifying distribution system models introduced in this paper offers model bus reduction of up to 98% with a simplification error as low as 0.2% (0.002 pu voltage). In contrast to existing methods of distribution system model simplification, which rely on topological inspection and linearization, the segment substitution method uses black-box segment data and an assumed simplified topology.

  2. Electric Power Distribution System Model Simplification Using Segment Substitution

    International Nuclear Information System (INIS)

    Reiman, Andrew P.; McDermott, Thomas E.; Akcakaya, Murat; Reed, Gregory F.

    2017-01-01

    Quasi-static time-series (QSTS) simulation is used to simulate the behavior of distribution systems over long periods of time (typically hours to years). The technique involves repeatedly solving the load-flow problem for a distribution system model and is useful for distributed energy resource (DER) planning. When a QSTS simulation has a small time step and a long duration, the computational burden of the simulation can be a barrier to integration into utility workflows. One way to relieve the computational burden is to simplify the system model. The segment substitution method of simplifying distribution system models introduced in this paper offers model bus reduction of up to 98% with a simplification error as low as 0.2% (0.002 pu voltage). Finally, in contrast to existing methods of distribution system model simplification, which rely on topological inspection and linearization, the segment substitution method uses black-box segment data and an assumed simplified topology.

  3. Distributed photovoltaic system evaluation by Arizona Public Service Company

    International Nuclear Information System (INIS)

    Lambeth, R.; Lepley, T.

    1993-01-01

    Arizona Public Service Company (APS) has performed a study of the APS system to (1) determine whether APS has high-value distributed applications of photovoltaics (PV), (2) quantify the value of a distributed PV system, (3) compare the APS results with the earlier PG ampersand E results and (4) estimate whether there will be significant market for these applications at APS. The study confirmed that there is a value to distributing PV generation throughout the utility distribution system. The breakeven cost for a PV system in APS' best location is $3.44/watt, in 1996 dollars. Feeders which meet all the criteria and which will be eligible for full benefits are relatively rare. However, a PV system will usually have more value if it is distributed rather than installed at a central station site

  4. Probabilistic analysis in normal operation of distribution system with distributed generation

    DEFF Research Database (Denmark)

    Villafafila-Robles, R.; Sumper, A.; Bak-Jensen, B.

    2011-01-01

    Nowadays, the incorporation of high levels of small-scale non-dispatchable distributed generation is leading to the transition from the traditional 'vertical' power system structure to a 'horizontally-operated' power system, where the distribution networks contain both stochastic generation...... and load. This fact increases the number of stochastic inputs and dependence structures between them need to be considered. The deterministic analysis is not enough to cope with these issues and a new approach is needed. Probabilistic analysis provides a better approach. Moreover, as distribution systems...

  5. A Distribution-class Locational Marginal Price (DLMP) Index for Enhanced Distribution Systems

    Science.gov (United States)

    Akinbode, Oluwaseyi Wemimo

    The smart grid initiative is the impetus behind changes that are expected to culminate into an enhanced distribution system with the communication and control infrastructure to support advanced distribution system applications and resources such as distributed generation, energy storage systems, and price responsive loads. This research proposes a distribution-class analog of the transmission LMP (DLMP) as an enabler of the advanced applications of the enhanced distribution system. The DLMP is envisioned as a control signal that can incentivize distribution system resources to behave optimally in a manner that benefits economic efficiency and system reliability and that can optimally couple the transmission and the distribution systems. The DLMP is calculated from a two-stage optimization problem; a transmission system OPF and a distribution system OPF. An iterative framework that ensures accurate representation of the distribution system's price sensitive resources for the transmission system problem and vice versa is developed and its convergence problem is discussed. As part of the DLMP calculation framework, a DCOPF formulation that endogenously captures the effect of real power losses is discussed. The formulation uses piecewise linear functions to approximate losses. This thesis explores, with theoretical proofs, the breakdown of the loss approximation technique when non-positive DLMPs/LMPs occur and discusses a mixed integer linear programming formulation that corrects the breakdown. The DLMP is numerically illustrated in traditional and enhanced distribution systems and its superiority to contemporary pricing mechanisms is demonstrated using price responsive loads. Results show that the impact of the inaccuracy of contemporary pricing schemes becomes significant as flexible resources increase. At high elasticity, aggregate load consumption deviated from the optimal consumption by up to about 45 percent when using a flat or time-of-use rate. Individual load

  6. Reliability planning in distributed electric energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Kahn, E.

    1978-10-01

    The goal of this paper is to develop tools for technology evaluation that address questions involving the economics of large-scale systems. The kind of cost discussed usually involves some dynamic aspect of the energy system. In particular, such properties as flexibility, stability, and resilience are features of entire systems. Special attention must be paid to the question of reliability, i.e., availability on demand. The storage problem and the planning for reliability in utility systems are the subjects of this paper. The introductory chapter addresses preliminary definitions--reliability planning, uncertainty, resilience, and other sensitivities. The study focuses on the contrast between conventional power generation technologies with controllable output and intermittent resources such as wind and solar electric conversion devices. The system studied is a stylized representation of California conditions. Significant differences were found in reliability planning requirements (and therefore costs) for systems dominated by central station plants as opposed to those dominated by intermittent resource technologies. It is argued that existing hydroelectric facilities need re-optimization. These plants provide the only currently existing bulk power storage in electric energy systems. 38 references. (MCW)

  7. Distributed Multi-propulsion Units System

    OpenAIRE

    原田, 正志; HARADA, Masashi

    2002-01-01

    Reduction of the weight of the propulsion system is important in the design of a stratospheric airship. However, it also important to increaseefficiency of the system because available energy generated by solar cells on the hull is quite limited. One solution to increase efficiency of the propulsion system is to use a stern propeller, the propeller mounted on the stern of the hull as shown in Figure 1. Mounted on the stern of the hull, the stern propeller is merged with the boundary layer of ...

  8. Automatic code generation for distributed robotic systems

    International Nuclear Information System (INIS)

    Jones, J.P.

    1993-01-01

    Hetero Helix is a software environment which supports relatively large robotic system development projects. The environment supports a heterogeneous set of message-passing LAN-connected common-bus multiprocessors, but the programming model seen by software developers is a simple shared memory. The conceptual simplicity of shared memory makes it an extremely attractive programming model, especially in large projects where coordinating a large number of people can itself become a significant source of complexity. We present results from three system development efforts conducted at Oak Ridge National Laboratory over the past several years. Each of these efforts used automatic software generation to create 10 to 20 percent of the system

  9. Distributed-Order Dynamic Systems Stability, Simulation, Applications and Perspectives

    CERN Document Server

    Jiao, Zhuang; Podlubny, Igor

    2012-01-01

    Distributed-order differential equations, a generalization of fractional calculus, are of increasing importance in many fields of science and engineering from the behaviour of complex dielectric media to the modelling of nonlinear systems. This Brief will broaden the toolbox available to researchers interested in modeling, analysis, control and filtering. It contains contextual material outlining the progression from integer-order, through fractional-order to distributed-order systems. Stability issues are addressed with graphical and numerical results highlighting the fundamental differences between constant-, integer-, and distributed-order treatments. The power of the distributed-order model is demonstrated with work on the stability of noncommensurate-order linear time-invariant systems. Generic applications of the distributed-order operator follow: signal processing and viscoelastic damping of a mass–spring set up. A new general approach to discretization of distributed-order derivatives and integrals ...

  10. Reliability assessment of distribution system with the integration of renewable distributed generation

    International Nuclear Information System (INIS)

    Adefarati, T.; Bansal, R.C.

    2017-01-01

    Highlights: • Addresses impacts of renewable DG on the reliability of the distribution system. • Multi-objective formulation for maximizing the cost saving with integration of DG. • Uses Markov model to study the stochastic characteristics of the major components. • The investigation is done using modified RBTS bus test distribution system. • Proposed approach is useful for electric utilities to enhance the reliability. - Abstract: Recent studies have shown that renewable energy resources will contribute substantially to future energy generation owing to the rapid depletion of fossil fuels. Wind and solar energy resources are major sources of renewable energy that have the ability to reduce the energy crisis and the greenhouse gases emitted by the conventional power plants. Reliability assessment is one of the key indicators to measure the impact of the renewable distributed generation (DG) units in the distribution networks and to minimize the cost that is associated with power outage. This paper presents a comprehensive reliability assessment of the distribution system that satisfies the consumer load requirements with the penetration of wind turbine generator (WTG), electric storage system (ESS) and photovoltaic (PV). A Markov model is proposed to access the stochastic characteristics of the major components of the renewable DG resources as well as their influence on the reliability of a conventional distribution system. The results obtained from the case studies have demonstrated the effectiveness of using WTG, ESS and PV to enhance the reliability of the conventional distribution system.

  11. Gas turbine control for islanding operation of distribution systems

    DEFF Research Database (Denmark)

    Mahat, Pukar; Chen, Zhe; Bak-Jensen, Birgitte

    2009-01-01

    Danish distribution systems are characterized by a significant penetration of small gas turbine generators (GTGs) and fixed speed wind turbine generators (WTGs). Island operation of these distribution systems are becoming a viable option for economical and technical reasons. However, stabilizing...... frequency in an islanded system is one of the major challenges. This paper presents three different gas turbine governors for possible operation of distribution systems in an islanding mode. Simulation results are presented to show the performance of these governors in grid connected and islanding mode....

  12. Distributed software framework and continuous integration in hydroinformatics systems

    Science.gov (United States)

    Zhou, Jianzhong; Zhang, Wei; Xie, Mengfei; Lu, Chengwei; Chen, Xiao

    2017-08-01

    When encountering multiple and complicated models, multisource structured and unstructured data, complex requirements analysis, the platform design and integration of hydroinformatics systems become a challenge. To properly solve these problems, we describe a distributed software framework and it’s continuous integration process in hydroinformatics systems. This distributed framework mainly consists of server cluster for models, distributed database, GIS (Geographic Information System) servers, master node and clients. Based on it, a GIS - based decision support system for joint regulating of water quantity and water quality of group lakes in Wuhan China is established.

  13. Distributed Energy Resources Interconnection Systems: Technology Review and Research Needs

    Energy Technology Data Exchange (ETDEWEB)

    Friedman, N. R.

    2002-09-01

    Interconnecting distributed energy resources (DER) to the electric utility grid (or Area Electric Power System, Area EPS) involves system engineering, safety, and reliability considerations. This report documents US DOE Distribution and Interconnection R&D (formerly Distributed Power Program) activities, furthering the development and safe and reliable integration of DER interconnected with our nation's electric power systems. The key to that is system integration and technology development of the interconnection devices that perform the functions necessary to maintain the safety, power quality, and reliability of the EPS when DER are connected to it.

  14. Distributed Sensor Coordination for Advanced Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Tumer, Kagan [Oregon State Univ., Corvallis, OR (United States)

    2013-07-31

    The ability to collect key system level information is critical to the safe, efficient and reliable operation of advanced energy systems. With recent advances in sensor development, it is now possible to push some level of decision making directly to computationally sophisticated sensors, rather than wait for data to arrive to a massive centralized location before a decision is made. This type of approach relies on networked sensors (called “agents” from here on) to actively collect and process data, and provide key control decisions to significantly improve both the quality/relevance of the collected data and the associating decision making. The technological bottlenecks for such sensor networks stem from a lack of mathematics and algorithms to manage the systems, rather than difficulties associated with building and deploying them. Indeed, traditional sensor coordination strategies do not provide adequate solutions for this problem. Passive data collection methods (e.g., large sensor webs) can scale to large systems, but are generally not suited to highly dynamic environments, such as advanced energy systems, where crucial decisions may need to be reached quickly and locally. Approaches based on local decisions on the other hand cannot guarantee that each agent performing its task (maximize an agent objective) will lead to good network wide solution (maximize a network objective) without invoking cumbersome coordination routines. There is currently a lack of algorithms that will enable self-organization and blend the efficiency of local decision making with the system level guarantees of global decision making, particularly when the systems operate in dynamic and stochastic environments. In this work we addressed this critical gap and provided a comprehensive solution to the problem of sensor coordination to ensure the safe, reliable, and robust operation of advanced energy systems. The differentiating aspect of the proposed work is in shifting the focus

  15. Distributed sensor coordination for advanced energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Tumer, Kagan [Oregon State Univ., Corvallis, OR (United States). School of Mechanical, Industrial and Manufacturing Engineering

    2015-03-12

    Motivation: The ability to collect key system level information is critical to the safe, efficient and reliable operation of advanced power systems. Recent advances in sensor technology have enabled some level of decision making directly at the sensor level. However, coordinating large numbers of sensors, particularly heterogeneous sensors, to achieve system level objectives such as predicting plant efficiency, reducing downtime or predicting outages requires sophisticated coordination algorithms. Indeed, a critical issue in such systems is how to ensure the interaction of a large number of heterogenous system components do not interfere with one another and lead to undesirable behavior. Objectives and Contributions: The long-term objective of this work is to provide sensor deployment, coordination and networking algorithms for large numbers of sensors to ensure the safe, reliable, and robust operation of advanced energy systems. Our two specific objectives are to: 1. Derive sensor performance metrics for heterogeneous sensor networks. 2. Demonstrate effectiveness, scalability and reconfigurability of heterogeneous sensor network in advanced power systems. The key technical contribution of this work is to push the coordination step to the design of the objective functions of the sensors, allowing networks of heterogeneous sensors to be controlled. By ensuring that the control and coordination is not specific to particular sensor hardware, this approach enables the design and operation of large heterogeneous sensor networks. In addition to the coordination coordination mechanism, this approach allows the system to be reconfigured in response to changing needs (e.g., sudden external events requiring new responses) or changing sensor network characteristics (e.g., sudden changes to plant condition). Impact: The impact of this work extends to a large class of problems relevant to the National Energy Technology Laboratory including sensor placement, heterogeneous sensor

  16. Smart intimation and location of faults in distribution system

    Science.gov (United States)

    Hari Krishna, K.; Srinivasa Rao, B.

    2018-04-01

    Location of faults in the distribution system is one of the most complicated problems that we are facing today. Identification of fault location and severity of fault within a short time is required to provide continuous power supply but fault identification and information transfer to the operator is the biggest challenge in the distribution network. This paper proposes a fault location method in the distribution system based on Arduino nano and GSM module with flame sensor. The main idea is to locate the fault in the distribution transformer by sensing the arc coming out from the fuse element. The biggest challenge in the distribution network is to identify the location and the severity of faults under different conditions. Well operated transmission and distribution systems will play a key role for uninterrupted power supply. Whenever fault occurs in the distribution system the time taken to locate and eliminate the fault has to be reduced. The proposed design was achieved with flame sensor and GSM module. Under faulty condition, the system will automatically send an alert message to the operator in the distribution system, about the abnormal conditions near the transformer, site code and its exact location for possible power restoration.

  17. Integrating security in a group oriented distributed system

    Science.gov (United States)

    Reiter, Michael; Birman, Kenneth; Gong, LI

    1992-01-01

    A distributed security architecture is proposed for incorporation into group oriented distributed systems, and in particular, into the Isis distributed programming toolkit. The primary goal of the architecture is to make common group oriented abstractions robust in hostile settings, in order to facilitate the construction of high performance distributed applications that can tolerate both component failures and malicious attacks. These abstractions include process groups and causal group multicast. Moreover, a delegation and access control scheme is proposed for use in group oriented systems. The focus is the security architecture; particular cryptosystems and key exchange protocols are not emphasized.

  18. 'Y' a distributed resource sharing system in nuclear research environment

    International Nuclear Information System (INIS)

    Popescu-Zeletin, R.

    1986-01-01

    The paper outlines the rationales for the transition from HMINET-2 to a distributed resource sharing system in Hahn-Meitner-Institute for Nuclear Research. The architecture and rationales for the planned new distributed resource system (Y) in HMI are outlined. The introduction of a distributed operating system is a prerequisite for a resource-sharing system. Y will provide not only the integration of networks of different qualities (high speed back-bone, LANs of different technologies, ports to national X.25 network and satellite) at hardware level, but also an integrated global user view of the whole system. This will be designed and implemented by decoupling the user-view from the hardware topology by introducing a netwide distributed operating system. (Auth.)

  19. A novel optimal distribution system planning framework implementing distributed generation in a deregulated electricity market

    International Nuclear Information System (INIS)

    Porkar, S.; Poure, P.; Abbaspour-Tehrani-fard, A.; Saadate, S.

    2010-01-01

    This paper introduces a new framework included mathematical model and a new software package interfacing two powerful softwares (MATLAB and GAMS) for obtaining the optimal distributed generation (DG) capacity sizing and sitting investments with capability to simulate large distribution system planning. The proposed optimization model allows minimizing total system planning costs for DG investment, DG operation and maintenance, purchase of power by the distribution companies (DISCOs) from transmission companies (TRANSCOs) and system power losses. The proposed model provides not only the DG size and site but also the new market price as well. Three different cases depending on system conditions and three different scenarios depending on different planning alternatives and electrical market structures, have been considered. They have allowed validating the economical and electrical benefits of introducing DG by solving the distribution system planning problem and by improving power quality of distribution system. DG installation increases the feeders' lifetime by reducing their loading and adds the benefit of using the existing distribution system for further load growth without the need for feeders upgrading. More, by investing in DG, the DISCO can minimize its total planning cost and reduce its customers' bills. (author)

  20. A novel optimal distribution system planning framework implementing distributed generation in a deregulated electricity market

    Energy Technology Data Exchange (ETDEWEB)

    Porkar, S. [Department of Electrical Engineering, Sharif University of Technology, Tehran (Iran); Groupe de Recherches en Electrotechnique et Electronique de Nancy, GREEN-UHP, Universite Henri Poincare de Nancy I, BP 239, 54506 Vandoeuvre les Nancy Cedex (France); Poure, P. [Laboratoire d' Instrumentation Electronique de Nancy, LIEN, EA 3440, Universite Henri Poincare de Nancy I, BP 239, 54506 Vandoeuvre les Nancy Cedex (France); Abbaspour-Tehrani-fard, A. [Department of Electrical Engineering, Sharif University of Technology, Tehran (Iran); Saadate, S. [Groupe de Recherches en Electrotechnique et Electronique de Nancy, GREEN-UHP, Universite Henri Poincare de Nancy I, BP 239, 54506 Vandoeuvre les Nancy Cedex (France)

    2010-07-15

    This paper introduces a new framework included mathematical model and a new software package interfacing two powerful softwares (MATLAB and GAMS) for obtaining the optimal distributed generation (DG) capacity sizing and sitting investments with capability to simulate large distribution system planning. The proposed optimization model allows minimizing total system planning costs for DG investment, DG operation and maintenance, purchase of power by the distribution companies (DISCOs) from transmission companies (TRANSCOs) and system power losses. The proposed model provides not only the DG size and site but also the new market price as well. Three different cases depending on system conditions and three different scenarios depending on different planning alternatives and electrical market structures, have been considered. They have allowed validating the economical and electrical benefits of introducing DG by solving the distribution system planning problem and by improving power quality of distribution system. DG installation increases the feeders' lifetime by reducing their loading and adds the benefit of using the existing distribution system for further load growth without the need for feeders upgrading. More, by investing in DG, the DISCO can minimize its total planning cost and reduce its customers' bills. (author)

  1. Distributed and recoverable digital control system

    Science.gov (United States)

    Stange, Kent (Inventor); Hess, Richard (Inventor); Kelley, Gerald B (Inventor); Rogers, Randy (Inventor)

    2010-01-01

    A real-time multi-tasking digital control system with rapid recovery capability is disclosed. The control system includes a plurality of computing units comprising a plurality of redundant processing units, with each of the processing units configured to generate one or more redundant control commands. One or more internal monitors are employed for detecting data errors in the control commands. One or more recovery triggers are provided for initiating rapid recovery of a processing unit if data errors are detected. The control system also includes a plurality of actuator control units each in operative communication with the computing units. The actuator control units are configured to initiate a rapid recovery if data errors are detected in one or more of the processing units. A plurality of smart actuators communicates with the actuator control units, and a plurality of redundant sensors communicates with the computing units.

  2. 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

  3. Distributed Autonomous Robotic Systems : the 12th International Symposium

    CERN Document Server

    Cho, Young-Jo

    2016-01-01

    This volume of proceedings includes 32 original contributions presented at the 12th International Symposium on Distributed Autonomous Robotic Systems (DARS 2014), held in November 2014. The selected papers in this volume are authored by leading researchers from Asia, Europe, and the Americas, thereby providing a broad coverage and perspective of the state-of-the-art technologies, algorithms, system architectures, and applications in distributed robotic systems. .

  4. Optimal dynamic control of resources in a distributed system

    Science.gov (United States)

    Shin, Kang G.; Krishna, C. M.; Lee, Yann-Hang

    1989-01-01

    The authors quantitatively formulate the problem of controlling resources in a distributed system so as to optimize a reward function and derive optimal control strategies using Markov decision theory. The control variables treated are quite general; they could be control decisions related to system configuration, repair, diagnostics, files, or data. Two algorithms for resource control in distributed systems are derived for time-invariant and periodic environments, respectively. A detailed example to demonstrate the power and usefulness of the approach is provided.

  5. Reliability worth assessment of radial systems with distributed generation

    OpenAIRE

    Bellart Llavall, Francesc Xavier

    2010-01-01

    With recent advances in technology, utilities generation (DG) on the distribution systems. Reliability worth is very important in power system planning and operation. Having a DG ensures reli increase the reliability worth. This research project presents the study of a radial distribution system and the impact of placing DG in order to increase the reliability worth. where a DG have to be placed. The reliability improvement is measured by different reliability indices tha...

  6. TTCN-3 for distributed testing embedded systems

    NARCIS (Netherlands)

    Blom, S.C.C.; Deiß, T.; Ioustinova, N.; Kontio, A.; Pol, van de J.C.; Rennoch, A.; Sidorova, N.; Virbitskaite, I.; Voronkov, A.

    2007-01-01

    Abstract. TTCN-3 is a standardized language for specifying and executing test suites that is particularly popular for testing embedded systems. Prior to testing embedded software in a target environment, the software is usually tested in the host environment. Executing in the host environment often

  7. Residential hot water distribution systems: Roundtablesession

    Energy Technology Data Exchange (ETDEWEB)

    Lutz, James D.; Klein, Gary; Springer, David; Howard, Bion D.

    2002-08-01

    Residential building practice currently ignores the lossesof energy and water caused by the poor design of hot water systems. Theselosses include: combustion and standby losses from water heaters, thewaste of water (and energy) while waiting for hot water to get to thepoint of use; the wasted heat as water cools down in the distributionsystem after a draw; heat losses from recirculation systems and thediscarded warmth of waste water as it runs down the drain. Severaltechnologies are available that save energy (and water) by reducing theselosses or by passively recovering heat from wastewater streams and othersources. Energy savings from some individual technologies are reported tobe as much as 30 percent. Savings calculations of prototype systemsincluding bundles of technologies have been reported above 50 percent.This roundtable session will describe the current practices, summarizethe results of past and ongoing studies, discuss ways to think about hotwater system efficiency, and point to areas of future study. We will alsorecommend further steps to reduce unnecessary losses from hot waterdistribution systems.

  8. Communications and Tracking Distributed Systems Evolution Study

    Science.gov (United States)

    Culpepper, William

    1990-01-01

    The Communications and Tracking (C & T) techniques and equipment to support evolutionary space station concepts are being analyzed. Evolutionary space station configurations and operational concepts are used to derive the results to date. A description of the C & T system based on future capability needs is presented. Included are the hooks and scars currently identified to support future growth.

  9. Energy Systems Integration: Demonstrating Distributed Resource Communications

    Energy Technology Data Exchange (ETDEWEB)

    2017-01-01

    Overview fact sheet about the Electric Power Research Institute (EPRI) and Schneider Electric Integrated Network Testbed for Energy Grid Research and Technology Experimentation (INTEGRATE) project at the Energy Systems Integration Facility. INTEGRATE is part of the U.S. Department of Energy's Grid Modernization Initiative.

  10. Distributed intelligent systems: a coordination perspective

    National Research Council Canada - National Science Library

    Bedrouni, Abdellah

    2009-01-01

    ... Computing, Electronic Business, Semantic Web, Bioinformatics, and Computational Biology will certainly influence the direction of future agent-oriented research and technologies. Over the next decade, it is thus expected that real-world problems will impose the emergence of truly-open, fully-scalable agent-oriented systems, spanning across di...

  11. A Distributed Intelligent E-Learning System

    Science.gov (United States)

    Kristensen, Terje

    2016-01-01

    An E-learning system based on a multi-agent (MAS) architecture combined with the Dynamic Content Manager (DCM) model of E-learning, is presented. We discuss the benefits of using such a multi-agent architecture. Finally, the MAS architecture is compared with a pure service-oriented architecture (SOA). This MAS architecture may also be used within…

  12. Coordination in Distributed Intelligent Systems Applications

    Science.gov (United States)

    2009-12-13

    order to reduce call blocking. The approach relies on several layers of agents, specifically, link agents that interact in link markets to pur- chase ...the AAMAS 03 Workshop on Humans and Multi-Agent Systems. Melbourne, Australia. I 0. Magnus Ljungberg, Andrew Lucas, The OASIS Air Traffic Management

  13. Optimistic protocol for partitioned distributed database systems

    International Nuclear Information System (INIS)

    Davidson, S.B.

    1982-01-01

    A protocol for transaction processing during partition failures is presented which guarantees mutual consistency between copies of data-items after repair is completed. The protocol is optimistic in that transactions are processed without restrictions during the failure; conflicts are detected at repair time using a precedence graph and are resolved by backing out transactions according to some backout strategy. The protocol is then evaluated using simulation and probabilistic modeling. In the simulation, several parameters are varied such as the number of transactions processed in a group, the type of transactions processed, the number of data-items present in the database, and the distribution of references to data-items. The simulation also uses different backout strategies. From these results we note conditions under which the protocol performs well, i.e., conditions under which the protocol backs out a small percentage of the transaction run. A probabilistic model is developed to estimate the expected number of transactions backed out using most of the above database and transaction parameters, and is shown to agree with simulation results. Suggestions are then made on how to improve the performance of the protocol. Insights gained from the simulation and probabilistic modeling are used to develop a backout strategy which takes into account individual transaction costs and attempts to minimize total backout cost. Although the problem of choosing transactions to minimize total backout cost is, in general, NP-complete, the backout strategy is efficient and produces very good results

  14. Development of total medical material distribution management system.

    Science.gov (United States)

    Uto, Y; Kumamoto, I

    1994-07-01

    Since September 1992, attempts have been made at Kagoshima University Hospital to develop the Medical Material Distribution Management System which helps to realize optimal hospital management as a subsystem of the Total Hospital Information System of Kagoshima University (THINK). As this system has been established, it has become possible for us to have an accurate grasp of the flow and stock of medical materials at our hospital. Furthermore, since September 1993, the Medical Material Distribution Management System has been improved and the Total Medical Material Distribution Management System has been smoothly introduced into the site of clinical practice. This system enables automatic demands for fees for treatment with specific instruments and materials covered by health insurance. It was difficult to predict the effect of this system, because no similar system had been developed in Japan. However, more satisfactory results than expected have been obtained since its introduction.

  15. Optimal Capacitor Bank Capacity and Placement in Distribution Systems with High Distributed Solar Power Penetration

    Energy Technology Data Exchange (ETDEWEB)

    Hodge, Brian S [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Mather, Barry A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Cho, Gyu-Jung [Sungkyunkwan University, Korea; Oh, Yun-Sik [Sungkyunkwan University, Korea; Kim, Min-Sung [Sungkyunkwan University, Korea; Kim, Ji-Soo [Sungkyunkwan University, Korea; Kim, Chul-Hwan [Sungkyunkwan University, Korea

    2018-02-01

    Capacitor banks have been generally installed and utilized to support distribution voltage during period of higher load or on longer, higher impedance, feeders. Installations of distributed energy resources in distribution systems are rapidly increasing, and many of these generation resources have variable and uncertain power output. These generators can significantly change the voltage profile across a feeder, and therefore when a new capacitor bank is needed analysis of optimal capacity and location of the capacitor bank is required. In this paper, we model a particular distribution system including essential equipment. An optimization method is adopted to determine the best capacity and location sets of the newly installed capacitor banks, in the presence of distributed solar power generation. Finally we analyze the optimal capacitor banks configuration through the optimization and simulation results.

  16. Control and Estimation of Distributed Parameter Systems

    CERN Document Server

    Kappel, F; Kunisch, K

    1998-01-01

    Consisting of 23 refereed contributions, this volume offers a broad and diverse view of current research in control and estimation of partial differential equations. Topics addressed include, but are not limited to - control and stability of hyperbolic systems related to elasticity, linear and nonlinear; - control and identification of nonlinear parabolic systems; - exact and approximate controllability, and observability; - Pontryagin's maximum principle and dynamic programming in PDE; and - numerics pertinent to optimal and suboptimal control problems. This volume is primarily geared toward control theorists seeking information on the latest developments in their area of expertise. It may also serve as a stimulating reader to any researcher who wants to gain an impression of activities at the forefront of a vigorously expanding area in applied mathematics.

  17. Emergency warning via automated distribution system

    International Nuclear Information System (INIS)

    Glasser, J.C.

    1981-01-01

    Due to the Three Mile Island Nuclear Power Plant accident of March 28, 1979, the Nuclear Regulatory Commission and the Federal Emergency Management Agency require a general upgrading of existing Emergency Preparedness Plans. NUREG-0654/FEMA REP-1, Criteria for Preparation and Evaluation of Radiological Emergency Response Plans and Preparedness in Support of Nuclear Power Plants, dated October 1980, describes the Emergency Plans required and includes the Plant Operator's Onsite Plan, as well as the State, County, and Local Offsite Plans. As part of these Emergency Preparedness Plans, an Emergency Notification System is required to alert the general population within the Emergency Planning Zone surrounding a Nuclear Power Plant that a general emergency has occurred and that they should tune to an Emergency Broadcast Station for further information and instructions. The emergency notification system for Beaver Valley Power Station is described. The system is the capability of alerting 100% of the population with 5 mi of Beaver Valley Power Station within 15 min, and the capability of alerting 100% of the population within 10 mi of Beaver Valley Power Station within 45 min

  18. 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.)

  19. Innovated feed water distributing system of VVER steam generators

    International Nuclear Information System (INIS)

    Matal, O.; Sousek, P.; Simo, T.; Lehota, M.; Lipka, J.; Slugen, V.

    2000-01-01

    Defects in feed water distributing system due to corrosion-erosion effects have been observed at many VVER 440 steam generators (SG). Therefore analysis of defects origin and consequently design development and testing of a new feed water distributing system were performed. System tests in-situ supported by calculations and comparison of measured and calculated data were focused on demonstration of long term reliable operation, definition of water flow and water chemical characteristics at the SG secondary side and their measurements and study of dynamic characteristics needed for the innovated feed water distributing system seismic features approval. The innovated feed water distributing system was installed in the SGs of two VVER units already. (author)

  20. Characteristics of the Audit Processes for Distributed Informatics Systems

    Directory of Open Access Journals (Sweden)

    Marius POPA

    2009-01-01

    Full Text Available The paper contains issues regarding: main characteristics and examples of the distributed informatics systems and main difference categories among them, concepts, principles, techniques and fields for auditing the distributed informatics systems, concepts and classes of the standard term, characteristics of this one, examples of standards, guidelines, procedures and controls for auditing the distributed informatics systems. The distributed informatics systems are characterized by the following issues: development process, resources, implemented functionalities, architectures, system classes, particularities. The audit framework has two sides: the audit process and auditors. The audit process must be led in accordance with the standard specifications in the IT&C field. The auditors must meet the ethical principles and they must have a high-level of professional skills and competence in IT&C field.

  1. Development of Nuclide Recognizing Prompt Radiation Distribution Monitoring System

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Uk Jae; Yoo, Dong Han; Kim, Hee Reyoung [Ulsan National Institute of Science and Technology, Ulsan (Korea, Republic of)

    2014-05-15

    The geographic data such as latitude, longitude and map image can be obtained by using GPS and digital map. Radiation data can be acquired by detector. Finally simultaneous visibility system can be operated by using CDMA. Existing radiation distribution monitoring system is based on random generated data. However the radiation distribution monitoring system is developed. It is based on real detected data. Connection between the detector and laptop which are located at a site place is operated by using Bluetooth. CDMA is used to simulate visibility system between laptop in a site place and server PC in the control office. Real map image is taken from digital map. Finally radiation distribution contour map on the real map image can be shown by using MATLAB. 5 figures appear which shows natural, {sup 137}Cs, {sup 131}I, artificial and total radiation dose rate. So this system can be used in everywhere to check the distribution of radiation with geographic information.

  2. System analysis and planning of a gas distribution network

    Energy Technology Data Exchange (ETDEWEB)

    Salas, Edwin F.M.; Farias, Helio Monteiro [AUTOMIND, Rio de Janeiro, RJ (Brazil); Costa, Carla V.R. [Universidade Salvador (UNIFACS), BA (Brazil)

    2009-07-01

    The increase in demand by gas consumers require that projects or improvements in gas distribution networks be made carefully and safely to ensure a continuous, efficient and economical supply. Gas distribution companies must ensure that the networks and equipment involved are defined and designed at the appropriate time to attend to the demands of the market. To do that a gas distribution network analysis and planning tool should use distribution networks and transmission models for the current situation and the future changes to be implemented. These models are used to evaluate project options and help in making appropriate decisions in order to minimize the capital investment in new components or simple changes in operational procedures. Gas demands are increasing and it is important that gas distribute design new distribution systems to ensure this growth, considering financial constraints of the company, as well as local legislation and regulation. In this study some steps of developing a flexible system that attends to those needs will be described. The analysis of distribution requires geographically referenced data for the models as well as an accurate connectivity and the attributes of the equipment. GIS systems are often used as a deposit center that holds the majority of this information. GIS systems are constantly updated as distribution network equipment is modified. The distribution network modeling gathered from this system ensures that the model represents the current network condition. The benefits of this architecture drastically reduce the creation and maintenance cost of the network models, because network components data are conveniently made available to populate the distribution network. This architecture ensures that the models are continually reflecting the reality of the distribution network. (author)

  3. Low Power Computing in Distributed Systems

    Science.gov (United States)

    2006-04-01

    performance applications. It has been adopted in embedded systems such as the Stargate from Crossbow [15] and the PASTA 4 0 0.1 0.2 0.3 0.4 (A) flo at...current consumption of the Stargate board is measured by an Agilent digital multimeter 34401A. The digital multimeter is connected with the PC for data...floating point operation vs. integer operation Power supply Digital multimeter Stargate board with Xscale processor 5 2.2 Library math function vs

  4. Seismic Fragility of the LANL Fire Water Distribution System

    Energy Technology Data Exchange (ETDEWEB)

    Greg Mertz

    2007-03-30

    The purpose of this report is to present the results of a site-wide system fragility assessment. This assessment focuses solely on the performance of the water distribution systems that supply Chemical and Metallurgy Research (CMR), Weapons Engineering and Tritium Facility (WETF), Radioactive Liquid Waste Treatment Facility (RLWTF), Waste Characterization, Reduction, Repackaging Facility (WCRRF), and Transuranic Waste Inspectable Storage Project (TWISP). The analysis methodology is based on the American Lifelines Alliance seismic fragility formulations for water systems. System fragilities are convolved with the 1995 LANL seismic hazards to develop failure frequencies. Acceptance is determined by comparing the failure frequencies to the DOE-1020 Performance Goals. This study concludes that: (1) If a significant number of existing isolation valves in the water distribution system are closed to dedicate the entire water system to fighting fires in specific nuclear facilities; (2) Then, the water distribution systems for WETF, RLWTF, WCRRF, and TWISP meet the PC-2 performance goal and the water distribution system for CMR is capable of surviving a 0.06g earthquake. A parametric study of the WETF water distribution system demonstrates that: (1) If a significant number of valves in the water distribution system are NOT closed to dedicate the entire water system to fighting fires in WETF; (2) Then, the water distribution system for WETF has an annual probability of failure on the order of 4 x 10{sup -3} that does not meet the PC-2 performance goal. Similar conclusions are expected for CMR, RLWTF, WCRRF, and TWISP. It is important to note that some of the assumptions made in deriving the results should be verified by personnel in the safety-basis office and may need to be incorporated in technical surveillance requirements in the existing authorization basis documentation if credit for availability of fire protection water is taken at the PC-2 level earthquake levels

  5. Seismic Fragility of the LANL Fire Water Distribution System

    International Nuclear Information System (INIS)

    Greg Mertz Jason Cardon Mike Salmon

    2007-01-01

    The purpose of this report is to present the results of a site-wide system fragility assessment. This assessment focuses solely on the performance of the water distribution systems that supply Chemical and Metallurgy Research (CMR), Weapons Engineering and Tritium Facility (WETF), Radioactive Liquid Waste Treatment Facility (RLWTF), Waste Characterization, Reduction, Repackaging Facility (WCRRF), and Transuranic Waste Inspectable Storage Project (TWISP). The analysis methodology is based on the American Lifelines Alliance seismic fragility formulations for water systems. System fragilities are convolved with the 1995 LANL seismic hazards to develop failure frequencies. Acceptance is determined by comparing the failure frequencies to the DOE-1020 Performance Goals. This study concludes that: (1) If a significant number of existing isolation valves in the water distribution system are closed to dedicate the entire water system to fighting fires in specific nuclear facilities; (2) Then, the water distribution systems for WETF, RLWTF, WCRRF, and TWISP meet the PC-2 performance goal and the water distribution system for CMR is capable of surviving a 0.06g earthquake. A parametric study of the WETF water distribution system demonstrates that: (1) If a significant number of valves in the water distribution system are NOT closed to dedicate the entire water system to fighting fires in WETF; (2) Then, the water distribution system for WETF has an annual probability of failure on the order of 4 x 10 -3 that does not meet the PC-2 performance goal. Similar conclusions are expected for CMR, RLWTF, WCRRF, and TWISP. It is important to note that some of the assumptions made in deriving the results should be verified by personnel in the safety-basis office and may need to be incorporated in technical surveillance requirements in the existing authorization basis documentation if credit for availability of fire protection water is taken at the PC-2 level earthquake levels

  6. Clone tag detection in distributed RFID systems

    Science.gov (United States)

    Kamaludin, Hazalila; Mahdin, Hairulnizam

    2018-01-01

    Although Radio Frequency Identification (RFID) is poised to displace barcodes, security vulnerabilities pose serious challenges for global adoption of the RFID technology. Specifically, RFID tags are prone to basic cloning and counterfeiting security attacks. A successful cloning of the RFID tags in many commercial applications can lead to many serious problems such as financial losses, brand damage, safety and health of the public. With many industries such as pharmaceutical and businesses deploying RFID technology with a variety of products, it is important to tackle RFID tag cloning problem and improve the resistance of the RFID systems. To this end, we propose an approach for detecting cloned RFID tags in RFID systems with high detection accuracy and minimal overhead thus overcoming practical challenges in existing approaches. The proposed approach is based on consistency of dual hash collisions and modified count-min sketch vector. We evaluated the proposed approach through extensive experiments and compared it with existing baseline approaches in terms of execution time and detection accuracy under varying RFID tag cloning ratio. The results of the experiments show that the proposed approach outperforms the baseline approaches in cloned RFID tag detection accuracy. PMID:29565982

  7. Clone tag detection in distributed RFID systems.

    Science.gov (United States)

    Kamaludin, Hazalila; Mahdin, Hairulnizam; Abawajy, Jemal H

    2018-01-01

    Although Radio Frequency Identification (RFID) is poised to displace barcodes, security vulnerabilities pose serious challenges for global adoption of the RFID technology. Specifically, RFID tags are prone to basic cloning and counterfeiting security attacks. A successful cloning of the RFID tags in many commercial applications can lead to many serious problems such as financial losses, brand damage, safety and health of the public. With many industries such as pharmaceutical and businesses deploying RFID technology with a variety of products, it is important to tackle RFID tag cloning problem and improve the resistance of the RFID systems. To this end, we propose an approach for detecting cloned RFID tags in RFID systems with high detection accuracy and minimal overhead thus overcoming practical challenges in existing approaches. The proposed approach is based on consistency of dual hash collisions and modified count-min sketch vector. We evaluated the proposed approach through extensive experiments and compared it with existing baseline approaches in terms of execution time and detection accuracy under varying RFID tag cloning ratio. The results of the experiments show that the proposed approach outperforms the baseline approaches in cloned RFID tag detection accuracy.

  8. Application of robotics to distribution systems

    Energy Technology Data Exchange (ETDEWEB)

    Ramsbottom, W

    1986-06-01

    Robotic technology has been recognized as having potential application in lifeline maintenance and repair. A study was conducted to investigate the feasibility of utilizing robotics for this purpose, and to prepare a general design of appropriate equipment. Four lifeline tasks were selected as representative of the majority of work. Based on a detailed task decomposition, subtasks were rated on amenability to robot completion. All tasks are feasible, but in some cases special tooling is required. Based on today's robotics, it is concluded that a force reflecting master/slave telemanipulator, augmented by automatic robot tasks under a supervisory control system, provides the optimal approach. No commercially available products are currently adequate for lifeline work. A general design of the telemanipulator, which has been named the SKYARM has been developed, addressing all subsystems such as the manipulator, video, control power and insulation. The baseline system is attainable using today's technology. Improved performance and lower cost will be achieved through developments in artificial intelligence, machine vision, supervisory control and dielectrics. Immediate benefits to utilities include increased safety, better service and savings on a subset of maintenance tasks. In 3-5 years, the SKYARM will prove cost effective as a general purpose lifeline tool. 7 refs., 26 figs., 3 tabs.

  9. Distributed Coordination of Fractional Dynamical Systems with Exogenous Disturbances

    Directory of Open Access Journals (Sweden)

    Hongyong Yang

    2014-01-01

    Full Text Available Distributed coordination of fractional multiagent systems with external disturbances is studied. The state observer of fractional dynamical system is presented, and an adaptive pinning controller is designed for a little part of agents in multiagent systems without disturbances. This adaptive pinning controller with the state observer can ensure multiple agents' states reaching an expected reference tracking. Based on disturbance observers, the controllers are composited with the pinning controller and the state observer. By applying the stability theory of fractional order dynamical systems, the distributed coordination of fractional multiagent systems with external disturbances can be reached asymptotically.

  10. A distributed timing system for synchronizing control and data correlation

    International Nuclear Information System (INIS)

    Stettler, M.; Thuot, M.; Dalesio, L.R.; Cole, R.; Fite, C.; Slentz, G.; Warren, D.

    1992-01-01

    Synchronization is necessary in experimental physics machines to provide positive control over related events. The Ground Test Accelerator (GTA) timing system provides this function through a distributed control system, known as the Experimental Physics and Industrial Control System (EPICS). The EPICS timing system was designed to take advantage of a distributed architecture, and provides time stamping for synchronous data correlation as well as event control. The system has been successfully demonstrated on over a dozen controller nodes for operation and data analysis. The design of the hardware, software, and operational results are discussed. (author). 2 refs., 4 figs

  11. A distributed timing system for sychronizing control and data correlation

    International Nuclear Information System (INIS)

    Stettler, M.; Thout, M.; Dalesio, L.R.; Cole, R.; Fite, C.; Slentz, G.; Warren, D.

    1992-01-01

    Synchronization is necessary in experimental physics machines to provide positive control over related events. The Ground Test Accelerator (GTA) timing system provides this function through a distributed control system, known as the Experimental Physics and Industrial Control System (EPICS). The EPICS timing system was designed to take advantage of a distributed architecture, and provides time stamping for synchronous data correlation as well as event control. The system has been successfully demonstrated on over a dozen controller nodes for operation and data analysis. The design of the hardware, software, and operational results are discussed

  12. Formal Development and Verification of a Distributed Railway Control System

    DEFF Research Database (Denmark)

    Haxthausen, Anne Elisabeth; Peleska, Jan

    1999-01-01

    In this article we introduce the concept for a distributed railway control system and present the specification and verification of the main algorithm used for safe distributed control. Our design and verification approach is based on the RAISE method, starting with highly abstract algebraic...

  13. Information system for personnel work distribution in Kaunas Maironis gymnasium

    OpenAIRE

    Ivanauskaitė, Eglė

    2005-01-01

    This information technology master degree work. In this work it is made research of the task of teacher's work distribution acording to schoolchildren's individual studying plans. In this work it it analyzed the process of teacher's work distribution and their information needs. This information system was created in MS Visio surroundings and realized with MS SQL Server and VBA implements.

  14. Effect of the Distribution System on Drinking Water Quality

    Directory of Open Access Journals (Sweden)

    A. Grünwald

    2001-01-01

    Full Text Available The overall objective of this paper is to characterise the main aspects of water quality deterioration in a distribution system. The effect of residence time on chlorine uptake and the formation and evolution of disinfection by-products in distributed drinking water are discussed.

  15. Modeling Workflow Management in a Distributed Computing System ...

    African Journals Online (AJOL)

    Distributed computing is becoming increasingly important in our daily life. This is because it enables the people who use it to share information more rapidly and increases their productivity. A major characteristic feature or distributed computing is the explicit representation of process logic within a communication system, ...

  16. Evaluation of electric power distribution systems: period 1984/89

    International Nuclear Information System (INIS)

    Britto Filho, W.A. de; Pinto, V.G.

    1992-01-01

    The historical evolution of electric power distribution systems in Brazil, during 1984 to 1989 is described, showing the consumer market with the physical expansion of Distribution Networks and the results of quality from the services made by the companies to their clients. (C.G.C.)

  17. The Wigner distribution function applied to optical signals and systems

    NARCIS (Netherlands)

    Bastiaans, M.J.

    1978-01-01

    In this paper the Wigner distribution function has been introduced for optical signals and systems. The Wigner distribution function of an optical signal appears to be in close resemblance to the ray concept in geometrical optics. This resemblance reaches even farther: although derived from Fourier

  18. Automatic diagnosis and control of distributed solid state lighting systems

    NARCIS (Netherlands)

    Dong, J.; van Driel, W.D.; Zhang, G.Q.

    2011-01-01

    This paper describes a new design concept of automatically diagnosing and compensating LED degradations in distributed solid state lighting (SSL) systems. A failed LED may significantly reduce the overall illumination level, and destroy the uniform illumination distribution achieved by a nominal

  19. Formal Development and Verification of a Distributed Railway Control System

    DEFF Research Database (Denmark)

    Haxthausen, Anne Elisabeth; Peleska, Jan

    1998-01-01

    In this article we introduce the concept for a distributed railway control system and present the specification and verification of the main algorithm used for safe distributed control. Our design and verification approach is based on the RAISE method, starting with highly abstract algebraic spec...

  20. Combined operation of AC and DC distribution system with distributed generation units

    International Nuclear Information System (INIS)

    Noroozian, R.; Abedi, M.; Gharehpetian, G.

    2010-01-01

    This paper presents a DC distribution system which has been supplied by external AC systems as well as local DG units in order to demonstrate an overall solution to power quality issue. In this paper, the proposed operation method is demonstrated by simulation of power transfer between external AC systems, DG units, AC and DC loads. The power flow control in DC distribution system has been achieved by network converters and DG converters. Also, the mathematical model of the network, DG and load converters are obtained by using the average technique, which allows converter systems accurately simulated and control strategies for this converters is achieved. A suitable control strategy for network converters has been proposed that involves DC voltage droop regulator and novel instantaneous power regulation scheme. Also, a novel control technique has been proposed for DG converters. In this paper, a novel control system based on stationary and synchronously rotating reference frame has been proposed for load converters for supplying AC loads connected to the DC bus by balanced voltages. The several case studies have been studied based on proposed methods. The simulation results show that DC distribution systems including DG units can improve the power quality at the point of common coupling (PCC) in the power distribution system or industrial power system. (authors)

  1. An Ethernet LAN based distributed generation system load shedding strategy

    DEFF Research Database (Denmark)

    Wei, Mu; Chen, Zhe

    2011-01-01

    This paper firstly analyzes and compares various communication technologies, and proposes a communication system for a distributed generation system (DGS) with wind turbines. Then the paper presents a novel simulation method of considering the interactions between the communication system and power...

  2. Abstractions for Fault-Tolerant Distributed System Verification

    Science.gov (United States)

    Pike, Lee S.; Maddalon, Jeffrey M.; Miner, Paul S.; Geser, Alfons

    2004-01-01

    Four kinds of abstraction for the design and analysis of fault tolerant distributed systems are discussed. These abstractions concern system messages, faults, fault masking voting, and communication. The abstractions are formalized in higher order logic, and are intended to facilitate specifying and verifying such systems in higher order theorem provers.

  3. Automatic Management of Parallel and Distributed System Resources

    Science.gov (United States)

    Yan, Jerry; Ngai, Tin Fook; Lundstrom, Stephen F.

    1990-01-01

    Viewgraphs on automatic management of parallel and distributed system resources are presented. Topics covered include: parallel applications; intelligent management of multiprocessing systems; performance evaluation of parallel architecture; dynamic concurrent programs; compiler-directed system approach; lattice gaseous cellular automata; and sparse matrix Cholesky factorization.

  4. Using Sparse Capabilities in a Distributed Operating System

    NARCIS (Netherlands)

    Tanenbaum, Andrew S.; Mullender, Sape J.; van Renesse, Robbert

    Most distributed operating systems constructed to date have lacked a unifying mechanism for naming and protection. In this paper we discuss a system, Amoeba, that uses capabilities for naming and protecting objects. In contrast to traditional, centralized operating systems, in which capabilities are

  5. Software metrics: Software quality metrics for distributed systems. [reliability engineering

    Science.gov (United States)

    Post, J. V.

    1981-01-01

    Software quality metrics was extended to cover distributed computer systems. Emphasis is placed on studying embedded computer systems and on viewing them within a system life cycle. The hierarchy of quality factors, criteria, and metrics was maintained. New software quality factors were added, including survivability, expandability, and evolvability.

  6. Diffuse Ceiling Inlet Systems and the Room Air Distribution

    DEFF Research Database (Denmark)

    Nielsen, Peter V.; Jensen, Rasmus Lund; Rong, Li

    2010-01-01

    A diffuse ceiling inlet system is an air distribution system which is supplying the air through the whole ceiling. The system can remove a large heat load without creating draught in the room. The paper describes measurements in the case of both cooling and heating, and CFD predictions are given...

  7. Competition and Cooperation of Distributed Generation and Power System

    Science.gov (United States)

    Miyake, Masatoshi; Nanahara, Toshiya

    Advances in distributed generation technologies together with the deregulation of an electric power industry can lead to a massive introduction of distributed generation. Since most of distributed generation will be interconnected to a power system, coordination and competition between distributed generators and large-scale power sources would be a vital issue in realizing a more desirable energy system in the future. This paper analyzes competitions between electric utilities and cogenerators from the viewpoints of economic and energy efficiency based on the simulation results on an energy system including a cogeneration system. First, we examine best response correspondence of an electric utility and a cogenerator with a noncooperative game approach: we obtain a Nash equilibrium point. Secondly, we examine the optimum strategy that attains the highest social surplus and the highest energy efficiency through global optimization.

  8. Distributed control and instrumentation systems for future nuclear power plants

    International Nuclear Information System (INIS)

    Yan, G.; L'Archeveque, J.V.R.

    1976-01-01

    The centralized dual computer system philosophy has evolved as the key concept underlying the highly successful application of direct digital control in CANDU power reactors. After more than a decade, this basis philosophy bears re-examination in the light of advances in system concepts--notably distributed architectures. A number of related experimental programs, all aimed at exploring the prospects of applying distributed systems in Canadian nuclear power plants are discussed. It was realized from the outset that the successful application of distributed systems depends on the availability of a highly reliable, high capacity, low cost communications medium. Accordingly, an experimental facility has been established and experiments have been defined to address such problem areas as interprocess communications, distributed data base design and man/machine interfaces. The design of a first application to be installed at the NRU/NRX research reactors is progressing well

  9. Intelligent decision support algorithm for distribution system restoration.

    Science.gov (United States)

    Singh, Reetu; Mehfuz, Shabana; Kumar, Parmod

    2016-01-01

    Distribution system is the means of revenue for electric utility. It needs to be restored at the earliest if any feeder or complete system is tripped out due to fault or any other cause. Further, uncertainty of the loads, result in variations in the distribution network's parameters. Thus, an intelligent algorithm incorporating hybrid fuzzy-grey relation, which can take into account the uncertainties and compare the sequences is discussed to analyse and restore the distribution system. The simulation studies are carried out to show the utility of the method by ranking the restoration plans for a typical distribution system. This algorithm also meets the smart grid requirements in terms of an automated restoration plan for the partial/full blackout of network.

  10. Short circuit analysis of distribution system with integration of DG

    DEFF Research Database (Denmark)

    Su, Chi; Liu, Zhou; Chen, Zhe

    2014-01-01

    and as a result bring challenges to the network protection system. This problem has been frequently discussed in the literature, but mostly considering only the balanced fault situation. This paper presents an investigation on the influence of full converter based wind turbine (WT) integration on fault currents......Integration of distributed generation (DG) such as wind turbines into distribution system is increasing all around the world, because of the flexible and environmentally friendly characteristics. However, DG integration may change the pattern of the fault currents in the distribution system...... during both balanced and unbalanced faults. Major factors such as external grid short circuit power capacity, WT integration location, connection type of WT integration transformer are taken into account. In turn, the challenges brought to the protection system in the distribution network are presented...

  11. Short circuit protection for a power distribution system

    Science.gov (United States)

    Owen, J. R., III

    1969-01-01

    Sensing circuit detects when the output from a matrix is present and when it should be present. The circuit provides short circuit protection for a power distribution system where the selection of the driven load is accomplished by digital logic.

  12. Underground Water Distribution System, Fort Belvoir, Virginia. Leak Detection Survey

    National Research Council Canada - National Science Library

    1995-01-01

    .... The survey was conducted by myself, Donald Muir, Operations Coordinator, and required 12.25 working days. This was not a survey of the entire water distribution system but instead a survey of water mains 8 inch and larger...

  13. An Extensible, Ontology-based, Distributed Information System Architecture

    National Research Council Canada - National Science Library

    Chao, Alan I; Krikeles, Basil C; Lusignan, Angela E; Starczewski, Edward

    2003-01-01

    ...), which facilitates the construction of scalable, flexible distributed systems. XDA is based on a simple ontology mechanism that enables the definition and maintenance of high-level object models to capture the shared semantics necessary for interoperability...

  14. De-synchronization of the Distributed Refrigeration System

    DEFF Research Database (Denmark)

    Chen, Liang; Wisniewski, Rafal

    2010-01-01

    The supermarket refrigeration system typically has a distributed control structure, which simple and flexible, however, neglects interactions between its subsystems. Practice shows that these interactions lead to a synchronous operation of the display cases. It causes excessive wear...

  15. A Framework for Modeling and Analyzing Complex Distributed Systems

    National Research Council Canada - National Science Library

    Lynch, Nancy A; Shvartsman, Alex Allister

    2005-01-01

    Report developed under STTR contract for topic AF04-T023. This Phase I project developed a modeling language and laid a foundation for computational support tools for specifying, analyzing, and verifying complex distributed system designs...

  16. Massively Parallel Polar Decomposition on Distributed-Memory Systems

    KAUST Repository

    Ltaief, Hatem; Sukkari, Dalal E.; Esposito, Aniello; Nakatsukasa, Yuji; Keyes, David E.

    2018-01-01

    We present a high-performance implementation of the Polar Decomposition (PD) on distributed-memory systems. Building upon on the QR-based Dynamically Weighted Halley (QDWH) algorithm, the key idea lies in finding the best rational approximation

  17. Drinking water distribution systems: assessing and reducing risks

    National Research Council Canada - National Science Library

    Committee on Public Water Supply Distribution Systems: Assessing and Reducing Risks, National Research Council

    2006-01-01

    ... or well supplies to consumers’ taps. Spanning almost 1 million miles in the United States, distribution systems represent the vast majority of physical infrastructure for water supplies, and thus constitute the primary management...

  18. Efficient channel estimation in massive MIMO systems - a distributed approach

    KAUST Repository

    Al-Naffouri, Tareq Y.

    2016-01-01

    We present two efficient algorithms for distributed estimation of channels in massive MIMO systems. The two cases of 1) generic, and 2) sparse channels is considered. The algorithms estimate the impulse response for each channel observed

  19. System-wide power management control via clock distribution network

    Science.gov (United States)

    Coteus, Paul W.; Gara, Alan; Gooding, Thomas M.; Haring, Rudolf A.; Kopcsay, Gerard V.; Liebsch, Thomas A.; Reed, Don D.

    2015-05-19

    An apparatus, method and computer program product for automatically controlling power dissipation of a parallel computing system that includes a plurality of processors. A computing device issues a command to the parallel computing system. A clock pulse-width modulator encodes the command in a system clock signal to be distributed to the plurality of processors. The plurality of processors in the parallel computing system receive the system clock signal including the encoded command, and adjusts power dissipation according to the encoded command.

  20. Expert hierarchical selection of oil and gas distribution systems

    International Nuclear Information System (INIS)

    Frankel, E.G.

    1991-01-01

    Selection and design of oil and gas distribution systems involves a large number of decision makers and interest groups, as well as many alternative technical, financial, network, operating, management and regulatory options. Their objectives and measures of performance are different. Decision models can be effectively represented by hierarchical structures. A simple deterministic analytic hierarchy process is presented with application to oil and gas distribution systems

  1. Key issues and technical route of cyber physical distribution system

    Science.gov (United States)

    Zheng, P. X.; Chen, B.; Zheng, L. J.; Zhang, G. L.; Fan, Y. L.; Pei, T.

    2017-01-01

    Relying on the National High Technology Research and Development Program, this paper introduced the key issues in Cyber Physical Distribution System (CPDS), mainly includes: composite modelling method and interaction mechanism, system planning method, security defence technology, distributed control theory. Then on this basis, the corresponding technical route is proposed, and a more detailed research framework along with main schemes to be adopted is also presented.

  2. Quantitative assessments of distributed systems methodologies and techniques

    CERN Document Server

    Bruneo, Dario

    2015-01-01

    Distributed systems employed in critical infrastructures must fulfill dependability, timeliness, and performance specifications. Since these systems most often operate in an unpredictable environment, their design and maintenance require quantitative evaluation of deterministic and probabilistic timed models. This need gave birth to an abundant literature devoted to formal modeling languages combined with analytical and simulative solution techniques The aim of the book is to provide an overview of techniques and methodologies dealing with such specific issues in the context of distributed

  3. A Comparative Study of Distribution System Parameter Estimation Methods

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Yannan; Williams, Tess L.; Gourisetti, Sri Nikhil Gup

    2016-07-17

    In this paper, we compare two parameter estimation methods for distribution systems: residual sensitivity analysis and state-vector augmentation with a Kalman filter. These two methods were originally proposed for transmission systems, and are still the most commonly used methods for parameter estimation. Distribution systems have much lower measurement redundancy than transmission systems. Therefore, estimating parameters is much more difficult. To increase the robustness of parameter estimation, the two methods are applied with combined measurement snapshots (measurement sets taken at different points in time), so that the redundancy for computing the parameter values is increased. The advantages and disadvantages of both methods are discussed. The results of this paper show that state-vector augmentation is a better approach for parameter estimation in distribution systems. Simulation studies are done on a modified version of IEEE 13-Node Test Feeder with varying levels of measurement noise and non-zero error in the other system model parameters.

  4. A distributed data base management system. [for Deep Space Network

    Science.gov (United States)

    Bryan, A. I.

    1975-01-01

    Major system design features of a distributed data management system for the NASA Deep Space Network (DSN) designed for continuous two-way deep space communications are described. The reasons for which the distributed data base utilizing third-generation minicomputers is selected as the optimum approach for the DSN are threefold: (1) with a distributed master data base, valid data is available in real-time to support DSN management activities at each location; (2) data base integrity is the responsibility of local management; and (3) the data acquisition/distribution and processing power of a third-generation computer enables the computer to function successfully as a data handler or as an on-line process controller. The concept of the distributed data base is discussed along with the software, data base integrity, and hardware used. The data analysis/update constraint is examined.

  5. [Origination of Pareto distribution in complex dynamic systems].

    Science.gov (United States)

    Chernavskiĭ, D S; Nikitin, A P; Chernavskaia, O D

    2008-01-01

    The Pareto distribution, whose probability density function can be approximated at sufficiently great chi as rho(chi) - chi(-alpha), where alpha > or = 2, is of crucial importance from both the theoretical and practical point of view. The main reason is its qualitative distinction from the normal (Gaussian) distribution. Namely, the probability of high deviations appears to be significantly higher. The conception of the universal applicability of the Gauss law remains to be widely distributed despite the lack of objective confirmation of this notion in a variety of application areas. The origin of the Pareto distribution in dynamic systems located in the gaussian noise field is considered. A simple one-dimensional model is discussed where the system response in a rather wide interval of the variable can be quite precisely approximated by this distribution.

  6. Energy and enthalpy distribution functions for a few physical systems.

    Science.gov (United States)

    Wu, K L; Wei, J H; Lai, S K; Okabe, Y

    2007-08-02

    The present work is devoted to extracting the energy or enthalpy distribution function of a physical system from the moments of the distribution using the maximum entropy method. This distribution theory has the salient traits that it utilizes only the experimental thermodynamic data. The calculated distribution functions provide invaluable insight into the state or phase behavior of the physical systems under study. As concrete evidence, we demonstrate the elegance of the distribution theory by studying first a test case of a two-dimensional six-state Potts model for which simulation results are available for comparison, then the biphasic behavior of the binary alloy Na-K whose excess heat capacity, experimentally observed to fall in a narrow temperature range, has yet to be clarified theoretically, and finally, the thermally induced state behavior of a collection of 16 proteins.

  7. Illustration of distributed generation effects on protection system coordination

    Science.gov (United States)

    Alawami, Hussain Adnan

    Environmental concerns, market forces, and emergence of new technologies have recently resulted in restructuring electric utility from vertically integrated networks to competitive deregulated entities. Distributed generation (DG) is playing a major role in such deregulated markets. When they are installed in small amounts and small sizes, their impacts on the system may be negligible. When their penetration levels increase as well as their sizes, however, they may start affecting the system performance from more than one aspect. Power system protection needs to be re-assessed after the emergence of DG. This thesis attempts to illustrate the impact of DG on the power system protection coordination. It will study the operation of the impedance relays, fuses, reclosers and overcurrent relays when a DG is added to the distribution network. Different DG sizes, distances from the network and locations within the distribution system will be considered. Power system protection coordination is very sensitive to the DG size where it is not for the DG distance. DG location has direct impact on the operation of the protective devices especially when it is inserted in the middle point of the distribution system. Key Words, Distributed Generation, Impedance relay, fuses, reclosers, overcurrent relays, power system protection coordination.

  8. Distributed model based control of multi unit evaporation systems

    International Nuclear Information System (INIS)

    Yudi Samyudia

    2006-01-01

    In this paper, we present a new approach to the analysis and design of distributed control systems for multi-unit plants. The approach is established after treating the effect of recycled dynamics as a gap metric uncertainty from which a distributed controller can be designed sequentially for each unit to tackle the uncertainty. We then use a single effect multi-unit evaporation system to illustrate how the proposed method is used to analyze different control strategies and to systematically achieve a better closed-loop performance using a distributed model-based controller

  9. Distributed data base systems with special emphasis toward POREL

    Science.gov (United States)

    Neuhold, E. J.

    1984-01-01

    In the last few years a number of research and advanced development projects have resulted in distributed data base management prototypes. POREL, developed at the University of Stuttgart, is a multiuser, distributed, relational system developed for wide and local area networks of minicomputers and advanced micros. The general objectives of such data base systems and the architecture of POREL are discussed. In addition a comparison of some of the the existing distributed DMBS is included to provide the reader with information about the current state of the art.

  10. Modeling and optimization of parallel and distributed embedded systems

    CERN Document Server

    Munir, Arslan; Ranka, Sanjay

    2016-01-01

    This book introduces the state-of-the-art in research in parallel and distributed embedded systems, which have been enabled by developments in silicon technology, micro-electro-mechanical systems (MEMS), wireless communications, computer networking, and digital electronics. These systems have diverse applications in domains including military and defense, medical, automotive, and unmanned autonomous vehicles. The emphasis of the book is on the modeling and optimization of emerging parallel and distributed embedded systems in relation to the three key design metrics of performance, power and dependability.

  11. Synchronization Methods for Three Phase Distributed Power Generation Systems

    DEFF Research Database (Denmark)

    Timbus, Adrian Vasile; Teodorescu, Remus; Blaabjerg, Frede

    2005-01-01

    Nowadays, it is a general trend to increase the electricity production using Distributed Power Generation Systems (DPGS) based on renewable energy resources such as wind, sun or hydrogen. If these systems are not properly controlled, their connection to the utility network can generate problems...... on the grid side. Therefore, considerations about power generation, safe running and grid synchronization must be done before connecting these systems to the utility network. This paper is mainly dealing with the grid synchronization issues of distributed systems. An overview of the synchronization methods...

  12. Comparing Different Fault Identification Algorithms in Distributed Power System

    Science.gov (United States)

    Alkaabi, Salim

    A power system is a huge complex system that delivers the electrical power from the generation units to the consumers. As the demand for electrical power increases, distributed power generation was introduced to the power system. Faults may occur in the power system at any time in different locations. These faults cause a huge damage to the system as they might lead to full failure of the power system. Using distributed generation in the power system made it even harder to identify the location of the faults in the system. The main objective of this work is to test the different fault location identification algorithms while tested on a power system with the different amount of power injected using distributed generators. As faults may lead the system to full failure, this is an important area for research. In this thesis different fault location identification algorithms have been tested and compared while the different amount of power is injected from distributed generators. The algorithms were tested on IEEE 34 node test feeder using MATLAB and the results were compared to find when these algorithms might fail and the reliability of these methods.

  13. 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...

  14. Design of Distributed Engine Control Systems with Uncertain Delay.

    Directory of Open Access Journals (Sweden)

    Xiaofeng Liu

    Full Text Available Future gas turbine engine control systems will be based on distributed architecture, in which, the sensors and actuators will be connected to the controllers via a communication network. The performance of the distributed engine control (DEC is dependent on the network performance. This study introduces a distributed control system architecture based on a networked cascade control system (NCCS. Typical turboshaft engine-distributed controllers are designed based on the NCCS framework with a H∞ output feedback under network-induced time delays and uncertain disturbances. The sufficient conditions for robust stability are derived via the Lyapunov stability theory and linear matrix inequality approach. Both numerical and hardware-in-loop simulations illustrate the effectiveness of the presented method.

  15. Design of Distributed Engine Control Systems with Uncertain Delay.

    Science.gov (United States)

    Liu, Xiaofeng; Li, Yanxi; Sun, Xu

    Future gas turbine engine control systems will be based on distributed architecture, in which, the sensors and actuators will be connected to the controllers via a communication network. The performance of the distributed engine control (DEC) is dependent on the network performance. This study introduces a distributed control system architecture based on a networked cascade control system (NCCS). Typical turboshaft engine-distributed controllers are designed based on the NCCS framework with a H∞ output feedback under network-induced time delays and uncertain disturbances. The sufficient conditions for robust stability are derived via the Lyapunov stability theory and linear matrix inequality approach. Both numerical and hardware-in-loop simulations illustrate the effectiveness of the presented method.

  16. Distributed computing environments for future space control systems

    Science.gov (United States)

    Viallefont, Pierre

    1993-01-01

    The aim of this paper is to present the results of a CNES research project on distributed computing systems. The purpose of this research was to study the impact of the use of new computer technologies in the design and development of future space applications. The first part of this study was a state-of-the-art review of distributed computing systems. One of the interesting ideas arising from this review is the concept of a 'virtual computer' allowing the distributed hardware architecture to be hidden from a software application. The 'virtual computer' can improve system performance by adapting the best architecture (addition of computers) to the software application without having to modify its source code. This concept can also decrease the cost and obsolescence of the hardware architecture. In order to verify the feasibility of the 'virtual computer' concept, a prototype representative of a distributed space application is being developed independently of the hardware architecture.

  17. Grid Monitoring and Advanced Control of Distributed Power Generation Systems

    DEFF Research Database (Denmark)

    Timbus, Adrian Vasile

    . As an example, the latest published grid codes stress the ability of distributed generators, especially wind turbines, to stay connected during short grid disturbances and in addition to provide active/reactive power control at the point of common coupling. Based on the above facts, the need for improving...... reported in some countries creating concerns about power system stability. This leads to a continuous evolution of grid interconnection requirements towards a better controllability of generated power and an enhanced contribution of distributed power generation systems to power system stability...... and adding more features to the control of distributed power generation systems (DPGS) arises. As a consequence, this thesis focuses on grid monitoring methods and possible approaches in control in order to obtain a more reliable and  exible power generation system during normal and faulty grid conditions...

  18. MAC, A System for Automatically IPR Identification, Collection and Distribution

    Science.gov (United States)

    Serrão, Carlos

    Controlling Intellectual Property Rights (IPR) in the Digital World is a very hard challenge. The facility to create multiple bit-by-bit identical copies from original IPR works creates the opportunities for digital piracy. One of the most affected industries by this fact is the Music Industry. The Music Industry has supported huge losses during the last few years due to this fact. Moreover, this fact is also affecting the way that music rights collecting and distributing societies are operating to assure a correct music IPR identification, collection and distribution. In this article a system for automating this IPR identification, collection and distribution is presented and described. This system makes usage of advanced automatic audio identification system based on audio fingerprinting technology. This paper will present the details of the system and present a use-case scenario where this system is being used.

  19. A strategy for load balancing in distributed storage systems

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    Distributed storage systems are critical to the operation of the WLCG. These systems are not limited to fulfilling the long term storage requirements. They also serve data for computational analysis and other computational jobs. Distributed storage systems provide the ability to aggregate the storage and IO capacity of disks and tapes, but at the end of the day IO rate is still bound by the capabilities of the hardware, in particular the hard drives. Throughput of hard drives has increased dramatically over the decades, however for computational analysis IOPS is typically the limiting factor. To maximize return of investment, balancing IO load over available hardware is crucial. The task is made complicated by the common use of heterogeneous hardware and software environments that results from combining new and old hardware into a single storage system. This paper describes recent advances made in load balancing in the dCache distributed storage system. We describe a set of common requirements for load balan...

  20. Foundations for Protecting Renewable-Rich Distribution Systems.

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, Abraham [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Brahma, Sukumar [New Mexico State Univ., Las Cruces, NM (United States); Ranade, Satish [New Mexico State Univ., Las Cruces, NM (United States)

    2016-11-01

    High proliferation of Inverter Interfaced Distributed Energy Resources (IIDERs) into the electric distribution grid introduces new challenges to protection of such systems. This is because the existing protection systems are designed with two assumptions: 1) system is single-sourced, resulting in unidirectional fault current, and (2) fault currents are easily detectable due to much higher magnitudes compared to load currents. Due to the fact that most renewables interface with the grid though inverters, and inverters restrict their current output to levels close to the full load currents, both these assumptions are no longer valid - the system becomes multi-sourced, and overcurrent-based protection does not work. The primary scope of this study is to analyze the response of a grid-tied inverter to different faults in the grid, leading to new guidelines on protecting renewable-rich distribution systems.

  1. Simulation and energy analysis of distributed electric heating system

    Science.gov (United States)

    Yu, Bo; Han, Shenchao; Yang, Yanchun; Liu, Mingyuan

    2018-02-01

    Distributed electric heating system assistssolar heating systemby using air-source heat pump. Air-source heat pump as auxiliary heat sourcecan make up the defects of the conventional solar thermal system can provide a 24 - hour high - efficiency work. It has certain practical value and practical significance to reduce emissions and promote building energy efficiency. Using Polysun software the system is simulated and compared with ordinary electric boiler heating system. The simulation results show that upon energy request, 5844.5kW energy is saved and 3135kg carbon - dioxide emissions are reduced and5844.5 kWhfuel and energy consumption is decreased with distributed electric heating system. Theeffect of conserving energy and reducing emissions using distributed electric heating systemis very obvious.

  2. Optimal Placement and Sizing of Renewable Distributed Generations and Capacitor Banks into Radial Distribution Systems

    Directory of Open Access Journals (Sweden)

    Mahesh Kumar

    2017-06-01

    Full Text Available In recent years, renewable types of distributed generation in the distribution system have been much appreciated due to their enormous technical and environmental advantages. This paper proposes a methodology for optimal placement and sizing of renewable distributed generation(s (i.e., wind, solar and biomass and capacitor banks into a radial distribution system. The intermittency of wind speed and solar irradiance are handled with multi-state modeling using suitable probability distribution functions. The three objective functions, i.e., power loss reduction, voltage stability improvement, and voltage deviation minimization are optimized using advanced Pareto-front non-dominated sorting multi-objective particle swarm optimization method. First a set of non-dominated Pareto-front data are called from the algorithm. Later, a fuzzy decision technique is applied to extract the trade-off solution set. The effectiveness of the proposed methodology is tested on the standard IEEE 33 test system. The overall results reveal that combination of renewable distributed generations and capacitor banks are dominant in power loss reduction, voltage stability and voltage profile improvement.

  3. 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.

  4. Distributed Electrical Energy Systems: Needs, Concepts, Approaches and Vision

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yingchen [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Zhang, Jun [University of Denver; Gao, Wenzhong [University of Denver; Zheng, Xinhu [University of Minnesota; Yang, Liuqing [Colorado State University; Hao, Jun [University of Denver; Dai, Xiaoxiao [University of Denver

    2017-09-01

    Intelligent distributed electrical energy systems (IDEES) are featured by vast system components, diversifled component types, and difficulties in operation and management, which results in that the traditional centralized power system management approach no longer flts the operation. Thus, it is believed that the blockchain technology is one of the important feasible technical paths for building future large-scale distributed electrical energy systems. An IDEES is inherently with both social and technical characteristics, as a result, a distributed electrical energy system needs to be divided into multiple layers, and at each layer, a blockchain is utilized to model and manage its logic and physical functionalities. The blockchains at difierent layers coordinate with each other and achieve successful operation of the IDEES. Speciflcally, the multi-layer blockchains, named 'blockchain group', consist of distributed data access and service blockchain, intelligent property management blockchain, power system analysis blockchain, intelligent contract operation blockchain, and intelligent electricity trading blockchain. It is expected that the blockchain group can be self-organized into a complex, autonomous and distributed IDEES. In this complex system, frequent and in-depth interactions and computing will derive intelligence, and it is expected that such intelligence can bring stable, reliable and efficient electrical energy production, transmission and consumption.

  5. Network characteristics emerging from agent interactions in balanced distributed system.

    Science.gov (United States)

    Salman, Mahdi Abed; Bertelle, Cyrille; Sanlaville, Eric

    2015-01-01

    A distributed computing system behaves like a complex network, the interactions between nodes being essential information exchanges and migrations of jobs or services to execute. These actions are performed by software agents, which behave like the members of social networks, cooperating and competing to obtain knowledge and services. The load balancing consists in distributing the load evenly between system nodes. It aims at enhancing the resource usage. A load balancing strategy specifies scenarios for the cooperation. Its efficiency depends on quantity, accuracy, and distribution of available information. Nevertheless, the distribution of information on the nodes, together with the initial network structure, may create different logical network structures. In this paper, different load balancing strategies are tested on different network structures using a simulation. The four tested strategies are able to distribute evenly the load so that the system reaches a steady state (the mean response time of the jobs is constant), but it is shown that a given strategy indeed behaves differently according to structural parameters and information spreading. Such a study, devoted to distributed computing systems (DCSs), can be useful to understand and drive the behavior of other complex systems.

  6. Simulation model of load balancing in distributed computing systems

    Science.gov (United States)

    Botygin, I. A.; Popov, V. N.; Frolov, S. G.

    2017-02-01

    The availability of high-performance computing, high speed data transfer over the network and widespread of software for the design and pre-production in mechanical engineering have led to the fact that at the present time the large industrial enterprises and small engineering companies implement complex computer systems for efficient solutions of production and management tasks. Such computer systems are generally built on the basis of distributed heterogeneous computer systems. The analytical problems solved by such systems are the key models of research, but the system-wide problems of efficient distribution (balancing) of the computational load and accommodation input, intermediate and output databases are no less important. The main tasks of this balancing system are load and condition monitoring of compute nodes, and the selection of a node for transition of the user’s request in accordance with a predetermined algorithm. The load balancing is one of the most used methods of increasing productivity of distributed computing systems through the optimal allocation of tasks between the computer system nodes. Therefore, the development of methods and algorithms for computing optimal scheduling in a distributed system, dynamically changing its infrastructure, is an important task.

  7. Fluid moderator control system reactor internals distribution system

    International Nuclear Information System (INIS)

    Fensterer, H.F.; Klassen, W.E.; Veronesi, L.; Boyle, D.E.; Salton, R.B.

    1987-01-01

    This patent describes a spectral shift pressurized water nuclear reactor employing a low neutron moderating fluid for the spectral shift including a reactor pressure vessel, a core comprising a plurality of fuel assemblies, a core support plate, apparatus comprising means for penetrating the reactor vessel for introducing the moderating fluid into the reactor vessel. Means associated with the core support plate for directly distributing the moderating fluid to and from the fuel assemblies comprises at least one inlet flow channel in the core plate; branch inlet feed lines connect to the inlet flow channel in the core plate; vertical inlet flow lines flow connected to the branch inlet feed lines; each vertical flow line communicates with a fuel assembly; the distribution means further comprise lines serving as return flow lines, each of which is connected to one of the fuel assemblies; branch exit flow lines in the core plate flow connected to the return flow lines of the fuel assembly; and at least one outlet flow channel flow connected to the branch exit flow lines; and a flow port interposed between the penetration means and the distribution means for flow connecting the penetration means with the distribution means

  8. Distribution System Reliability Analysis for Smart Grid Applications

    Science.gov (United States)

    Aljohani, Tawfiq Masad

    Reliability of power systems is a key aspect in modern power system planning, design, and operation. The ascendance of the smart grid concept has provided high hopes of developing an intelligent network that is capable of being a self-healing grid, offering the ability to overcome the interruption problems that face the utility and cost it tens of millions in repair and loss. To address its reliability concerns, the power utilities and interested parties have spent extensive amount of time and effort to analyze and study the reliability of the generation and transmission sectors of the power grid. Only recently has attention shifted to be focused on improving the reliability of the distribution network, the connection joint between the power providers and the consumers where most of the electricity problems occur. In this work, we will examine the effect of the smart grid applications in improving the reliability of the power distribution networks. The test system used in conducting this thesis is the IEEE 34 node test feeder, released in 2003 by the Distribution System Analysis Subcommittee of the IEEE Power Engineering Society. The objective is to analyze the feeder for the optimal placement of the automatic switching devices and quantify their proper installation based on the performance of the distribution system. The measures will be the changes in the reliability system indices including SAIDI, SAIFI, and EUE. The goal is to design and simulate the effect of the installation of the Distributed Generators (DGs) on the utility's distribution system and measure the potential improvement of its reliability. The software used in this work is DISREL, which is intelligent power distribution software that is developed by General Reliability Co.

  9. Description of a 20 Kilohertz power distribution system

    Science.gov (United States)

    Hansen, I. G.

    1986-01-01

    A single phase, 440 VRMS, 20 kHz power distribution system with a regulated sinusoidal wave form is discussed. A single phase power system minimizes the wiring, sensing, and control complexities required in a multi-sourced redundantly distributed power system. The single phase addresses only the distribution link; mulitphase lower frequency inputs and outputs accommodation techniques are described. While the 440 V operating potential was initially selected for aircraft operating below 50,000 ft, this potential also appears suitable for space power systems. This voltage choice recognizes a reasonable upper limit for semiconductor ratings, yet will direct synthesis of 220 V, 3 power. A 20 kHz operating frequency was selected to be above the range of audibility, minimize the weight of reactive components, yet allow the construction of single power stages of 25 to 30 kW. The regulated sinusoidal distribution system has several advantages. With a regulated voltage, most ac/dc conversions involve rather simple transformer rectifier applications. A sinusoidal distribution system, when used in conjunction with zero crossing switching, represents a minimal source of EMI. The present state of 20 kHz power technology includes computer controls of voltage and/or frequency, low inductance cable, current limiting circuit protection, bi-directional power flow, and motor/generator operating using standard induction machines. A status update and description of each of these items and their significance is presented.

  10. Reliable file sharing in distributed operating system using web RTC

    Science.gov (United States)

    Dukiya, Rajesh

    2017-12-01

    Since, the evolution of distributed operating system, distributed file system is come out to be important part in operating system. P2P is a reliable way in Distributed Operating System for file sharing. It was introduced in 1999, later it became a high research interest topic. Peer to Peer network is a type of network, where peers share network workload and other load related tasks. A P2P network can be a period of time connection, where a bunch of computers connected by a USB (Universal Serial Bus) port to transfer or enable disk sharing i.e. file sharing. Currently P2P requires special network that should be designed in P2P way. Nowadays, there is a big influence of browsers in our life. In this project we are going to study of file sharing mechanism in distributed operating system in web browsers, where we will try to find performance bottlenecks which our research will going to be an improvement in file sharing by performance and scalability in distributed file systems. Additionally, we will discuss the scope of Web Torrent file sharing and free-riding in peer to peer networks.

  11. Energy system analysis of fuel cells and distributed generation

    DEFF Research Database (Denmark)

    Mathiesen, Brian Vad; Lund, Henrik

    2007-01-01

    This chapter introduces Energy System Analysis methodologies and tools, which can be used for identifying the best application of different Fuel Cell (FC) technologies to different regional or national energy systems. The main point is that the benefits of using FC technologies indeed depend...... on the energy system in which they are used. Consequently, coherent energy systems analyses of specific and complete energy systems must be conducted in order to evaluate the benefits of FC technologies and in order to be able to compare alternative solutions. In relation to distributed generation, FC...... technologies are very often connected to the use of hydrogen, which has to be provided e.g. from electrolysers. Decentralised and distributed generation has the possibility of improving the overall energy efficiency and flexibility of energy systems. Therefore, energy system analysis tools and methodologies...

  12. PanDA: distributed production and distributed analysis system for ATLAS

    International Nuclear Information System (INIS)

    Maeno, T

    2008-01-01

    A new distributed software system was developed in the fall of 2005 for the ATLAS experiment at the LHC. This system, called PANDA, provides an integrated service architecture with late binding of jobs, maximal automation through layered services, tight binding with ATLAS Distributed Data Management system [1], advanced error discovery and recovery procedures, and other features. In this talk, we will describe the PANDA software system. Special emphasis will be placed on the evolution of PANDA based on one and half year of real experience in carrying out Computer System Commissioning data production [2] for ATLAS. The architecture of PANDA is well suited for the computing needs of the ATLAS experiment, which is expected to be one of the first HEP experiments to operate at the petabyte scale

  13. Cosmological implications of the redshift distribution of QSO absorption systems

    International Nuclear Information System (INIS)

    Khare-Joshi, P.; Perry, J.J.

    1982-01-01

    We have used the observational data on QSO absorption redshifts, as compiled by Perry, Burbidge and Burbidge (1978) (hereafter PB 2 ), Drew (1978) and Weyman et al. (1979) (hereafter W 2 PT), to study various selection effects likely to affect the distribution of absorption redshifts and, then to determine the probable number distribution of absorbers per redshift interval of 0.1, as a function of z. The distribution obtained, assuming all the observed absorption to be intervening, is found to be statistically incompatible with the redshift distribution of galaxies with constant cross-section for any Friedman cosmology with zero cosmological constant and q 0 >= 0. Therefore, in order to eliminate the absorption systems which are plausibly intrinsic, we have applied the criterion suggested by W 2 PT and by the analysis of the distribution of absorption systems as a function of the relative velocity between the emitting and the absorbing gas, for the PB 2 data set; to wit, we have analysed the distributions obtained by assuming that those systems with relative velocity greater than 0.02 c, 0.02 c but not equal to 0.1 c to 0.11 c and 0.06 c respectively, or those systems without O VI and N V lines, are produced by the intervening galaxies. The results are discussed. (author)

  14. Discrete Wavelet Transform for Fault Locations in Underground Distribution System

    Science.gov (United States)

    Apisit, C.; Ngaopitakkul, A.

    2010-10-01

    In this paper, a technique for detecting faults in underground distribution system is presented. Discrete Wavelet Transform (DWT) based on traveling wave is employed in order to detect the high frequency components and to identify fault locations in the underground distribution system. The first peak time obtained from the faulty bus is employed for calculating the distance of fault from sending end. The validity of the proposed technique is tested with various fault inception angles, fault locations and faulty phases. The result is found that the proposed technique provides satisfactory result and will be very useful in the development of power systems protection scheme.

  15. Energy efficiency analysis of reconfigured distribution system for practical loads

    Directory of Open Access Journals (Sweden)

    Pawan Kumar

    2016-09-01

    Full Text Available In deregulated rate structure, the performance evaluation of distribution system for energy efficiency includes; loss minimization, improved power quality, loadability limit, reliability and availability of supply. Energy efficiency changes with the variation in loading pattern and the load behaviour. Further, the nature of load at each node is not explicitly of any one type rather their characteristics depend upon the node voltages. In most cases, load is assumed to be constant power (real and reactive. In this paper voltage dependent practical loads are represented with composite load model and the energy efficiency performance of distribution system for practical loads is evaluated in different configurations of 33-node system.

  16. Using Software Architectures for Designing Distributed Embedded Systems

    DEFF Research Database (Denmark)

    Christensen, Henrik Bærbak

    In this paper, we outline an on-going project of designing distributed embedded systems for closed-loop process control. The project is a joint effort between software architecture researchers and developers from two companies that produce commercial embedded process control systems. The project...... has a strong emphasis on software architectural issues and terminology in order to envision, design and analyze design alternatives. We present two results. First, we outline how focusing on software architecture, architectural issues and qualities are beneficial in designing distributed, embedded......, systems. Second, we present two different architectures for closed-loop process control and discuss benefits and reliabilities....

  17. Measuring the effects of heterogeneity on distributed systems

    Science.gov (United States)

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

    1991-01-01

    Distributed computer systems in daily use are becoming more and more heterogeneous. Currently, much of the design and analysis studies of such systems assume homogeneity. This assumption of homogeneity has been mainly driven by the resulting simplicity in modeling and analysis. A simulation study is presented which investigated the effects of heterogeneity on scheduling algorithms for hard real time distributed systems. In contrast to previous results which indicate that random scheduling may be as good as a more complex scheduler, this algorithm is shown to be consistently better than a random scheduler. This conclusion is more prevalent at high workloads as well as at high levels of heterogeneity.

  18. 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

  19. 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.

  20. 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