Sample records for network queuing system

  1. Some queuing network models of computer systems (United States)

    Herndon, E. S.


    Queuing network models of a computer system operating with a single workload type are presented. Program algorithms are adapted for use on the Texas Instruments SR-52 programmable calculator. By slightly altering the algorithm to process the G and H matrices row by row instead of column by column, six devices and an unlimited job/terminal population could be handled on the SR-52. Techniques are also introduced for handling a simple load dependent server and for studying interactive systems with fixed multiprogramming limits.


    Walter, H.


    The Network Queuing System, NQS, is a versatile batch and device queuing facility for a single Unix computer or a group of networked computers. With the Unix operating system as a common interface, the user can invoke the NQS collection of user-space programs to move batch and device jobs freely around the different computer hardware tied into the network. NQS provides facilities for remote queuing, request routing, remote status, queue status controls, batch request resource quota limits, and remote output return. This program was developed as part of an effort aimed at tying together diverse UNIX based machines into NASA's Numerical Aerodynamic Simulator Processing System Network. This revision of NQS allows for creating, deleting, adding and setting of complexes that aid in limiting the number of requests to be handled at one time. It also has improved device-oriented queues along with some revision of the displays. NQS was designed to meet the following goals: 1) Provide for the full support of both batch and device requests. 2) Support all of the resource quotas enforceable by the underlying UNIX kernel implementation that are relevant to any particular batch request and its corresponding batch queue. 3) Support remote queuing and routing of batch and device requests throughout the NQS network. 4) Support queue access restrictions through user and group access lists for all queues. 5) Enable networked output return of both output and error files to possibly remote machines. 6) Allow mapping of accounts across machine boundaries. 7) Provide friendly configuration and modification mechanisms for each installation. 8) Support status operations across the network, without requiring a user to log in on remote target machines. 9) Provide for file staging or copying of files for movement to the actual execution machine. To support batch and device requests, NQS v.2 implements three queue types--batch, device and pipe. Batch queues hold and prioritize batch requests

  3. Autocorrelation in queuing network-type production systems - revisited

    DEFF Research Database (Denmark)

    Nielsen, Erland Hejn


    In managing production systems, a strong emphasis is placed on the reduction of variance in specific transformation processes (e.g. for quality control purposes) and on controlling the level of variability in general, as for instance with the Bullwhip effect. However, the possible disturbing......, either production managers are missing important aspects in production planning, or the 'realistic' autocorrelation patterns inherent in actual production setups are not like those considered in the literature. In this paper, relevant and 'realistic' types of autocorrelation schemes are characterised...

  4. Autocorrelation in queuing network type production systems - revisited

    DEFF Research Database (Denmark)

    Nielsen, Erland Hejn

    Abstract When discussing flow-control matters with production managers , it is noteworthy that whereas there is normally great emphasis on the reduction of variance of specific transformation processes (quality control) as well as on level variability in general, as for instance represented......-production systems (Takahashi and Nakamura, 1998) establishes that autocorrelation plays definitely a non-negligible role in relation to the dimensioning as well as functioning of Kanban-controlled production flow lines . This must logically either imply that production managers are missing an important aspect...

  5. Modeling Air Traffic Management Technologies with a Queuing Network Model of the National Airspace System (United States)

    Long, Dou; Lee, David; Johnson, Jesse; Gaier, Eric; Kostiuk, Peter


    This report describes an integrated model of air traffic management (ATM) tools under development in two National Aeronautics and Space Administration (NASA) programs -Terminal Area Productivity (TAP) and Advanced Air Transport Technologies (AATT). The model is made by adjusting parameters of LMINET, a queuing network model of the National Airspace System (NAS), which the Logistics Management Institute (LMI) developed for NASA. Operating LMINET with models of various combinations of TAP and AATT will give quantitative information about the effects of the tools on operations of the NAS. The costs of delays under different scenarios are calculated. An extension of Air Carrier Investment Model (ACIM) under ASAC developed by the Institute for NASA maps the technologies' impacts on NASA operations into cross-comparable benefits estimates for technologies and sets of technologies.

  6. Decomposition method for analysis of closed queuing networks

    Directory of Open Access Journals (Sweden)

    Yu. G. Nesterov


    Full Text Available This article deals with the method to estimate the average residence time in nodes of closed queuing networks with priorities and a wide range of conservative disciplines to be served. The method is based on a decomposition of entire closed queuing network into a set of simple basic queuing systems such as M|GI|m|N for each node. The unknown average residence times in the network nodes are interrelated through a system of nonlinear equations. The fact that there is a solution of this system has been proved. An iterative procedure based on Newton-Kantorovich method is proposed for finding the solution of such system. This procedure provides fast convergence to solution. Today possibilities of proposed method are limited by known analytical solutions for simple basic queuing systems of M|GI|m|N type.

  7. Modelling traffic congestion using queuing networks

    Indian Academy of Sciences (India)

    Traffic Flow-Density diagrams are obtained using simple Jackson queuing network analysis. Such simple analytical models can be used to capture the effect of non- homogenous traffic. Keywords. Flow-density curves; uninterrupted traffic; Jackson networks. 1. Introduction. Traffic management has become very essential in ...

  8. Queuing theory and telecommunications networks and applications

    CERN Document Server

    Giambene, Giovanni


    This book provides a basic description of current networking technologies and protocols as well as important tools for network performance analysis based on queuing theory. The second edition adds selected contents in the first part of the book for what concerns: (i) the token bucket regulator and traffic shaping issues; (ii) the TCP protocol congestion control that has a significant part in current networking; (iii) basic satellite networking issues; (iv) adding details on QoS support in IP networks. The book is organized so that networking technologies and protocols (Part I) are first and are then followed by theory and exercises with applications to the different technologies and protocols (Part II). This book is intended as a textbook for master level courses in networking and telecommunications sectors.

  9. The Application of Phase Type Distributions for Modelling Queuing Systems

    Directory of Open Access Journals (Sweden)



    Full Text Available Queuing models are important tools for studying the performance of complex systems, but despite the substantial queuing theory literature, it is often necessary to use approximations in the case the system is nonmarkovian. Phase type distribution is by now indispensable tool in creation of queuing system models. The purpose of this paper is to suggest a method and software for evaluating queuing approximations. A numerical queuing model with priorities is used to explore the behaviour of exponential phase-type approximation of service-time distribution. The performance of queuing systems described in the event language is used for generating the set of states and transition matrix between them. Two examples of numerical models are presented – a queuing system model with priorities and a queuing system model with quality control.

  10. A hybrid queuing strategy for network traffic on scale-free networks (United States)

    Cai, Kai-Quan; Yu, Lu; Zhu, Yan-Bo


    In this paper, a hybrid queuing strategy (HQS) is proposed in traffic dynamics model on scale-free networks, where the delivery priority of packets in the queue is related to their distance to destination and the queue length of next jump. We compare the performance of the proposed HQS with that of the traditional first-in-first-out (FIFO) queuing strategy and the shortest-remaining-path-first (SRPF) queuing strategy proposed by Du et al. It is observed that the network traffic efficiency utilizing HQS with suitable value of parameter h can be further improved in the congestion state. Our work provides new insights for the understanding of the networked-traffic systems.

  11. Modeling Relief Demands in an Emergency Supply Chain System under Large-Scale Disasters Based on a Queuing Network

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    Xinhua He


    Full Text Available This paper presents a multiple-rescue model for an emergency supply chain system under uncertainties in large-scale affected area of disasters. The proposed methodology takes into consideration that the rescue demands caused by a large-scale disaster are scattered in several locations; the servers are arranged in multiple echelons (resource depots, distribution centers, and rescue center sites located in different places but are coordinated within one emergency supply chain system; depending on the types of rescue demands, one or more distinct servers dispatch emergency resources in different vehicle routes, and emergency rescue services queue in multiple rescue-demand locations. This emergency system is modeled as a minimal queuing response time model of location and allocation. A solution to this complex mathematical problem is developed based on genetic algorithm. Finally, a case study of an emergency supply chain system operating in Shanghai is discussed. The results demonstrate the robustness and applicability of the proposed model.

  12. Dynamic queuing transmission model for dynamic network loading

    DEFF Research Database (Denmark)

    Raovic, Nevena; Nielsen, Otto Anker; Prato, Carlo Giacomo


    This paper presents a new macroscopic multi-class dynamic network loading model called Dynamic Queuing Transmission Model (DQTM). The model utilizes ‘good’ properties of the Dynamic Queuing Model (DQM) and the Link Transmission Model (LTM) by offering a DQM consistent with the kinematic wave theory...... and allowing for the representation of multiple vehicle classes, queue spillbacks and shock waves. The model assumes that a link is split into a moving part plus a queuing part, and p that traffic dynamics are given by a triangular fundamental diagram. A case-study is investigated and the DQTM is compared...... for two vehicle classes. Moreover, the results show that the travel time will be underestimated without considering the shock wave property...

  13. An Improved Call Admission Control Mechanism with Prioritized Handoff Queuing Scheme for BWA Networks (United States)

    Chowdhury, Prasun; Saha Misra, Iti


    Nowadays, due to increased demand for using the Broadband Wireless Access (BWA) networks in a satisfactory manner a promised Quality of Service (QoS) is required to manage the seamless transmission of the heterogeneous handoff calls. To this end, this paper proposes an improved Call Admission Control (CAC) mechanism with prioritized handoff queuing scheme that aims to reduce dropping probability of handoff calls. Handoff calls are queued when no bandwidth is available even after the allowable bandwidth degradation of the ongoing calls and get admitted into the network when an ongoing call is terminated with a higher priority than the newly originated call. An analytical Markov model for the proposed CAC mechanism is developed to analyze various performance parameters. Analytical results show that our proposed CAC with handoff queuing scheme prioritizes the handoff calls effectively and reduces dropping probability of the system by 78.57% for real-time traffic without degrading the number of failed new call attempts. This results in the increased bandwidth utilization of the network.

  14. Capacity utilization study for aviation security cargo inspection queuing system (United States)

    Allgood, Glenn O.; Olama, Mohammed M.; Lake, Joe E.; Brumback, Daryl


    In this paper, we conduct performance evaluation study for an aviation security cargo inspection queuing system for material flow and accountability. The queuing model employed in our study is based on discrete-event simulation and processes various types of cargo simultaneously. Onsite measurements are collected in an airport facility to validate the queuing model. The overall performance of the aviation security cargo inspection system is computed, analyzed, and optimized for the different system dynamics. Various performance measures are considered such as system capacity, residual capacity, throughput, capacity utilization, subscribed capacity utilization, resources capacity utilization, subscribed resources capacity utilization, and number of cargo pieces (or pallets) in the different queues. These metrics are performance indicators of the system's ability to service current needs and response capacity to additional requests. We studied and analyzed different scenarios by changing various model parameters such as number of pieces per pallet, number of TSA inspectors and ATS personnel, number of forklifts, number of explosives trace detection (ETD) and explosives detection system (EDS) inspection machines, inspection modality distribution, alarm rate, and cargo closeout time. The increased physical understanding resulting from execution of the queuing model utilizing these vetted performance measures should reduce the overall cost and shipping delays associated with new inspection requirements.

  15. impact of queuing on call c queuing on call c queuing on call ...

    African Journals Online (AJOL)


    The concept of queuing is very useful in modell systems where traffic management is of utm importance. In GSM networks, traffic characteris have a random behaviour in terms of arrival; usu following a Poisson's distribution [ deployment of queuing in GSM traffic modelling can very useful in effective channel utilization.

  16. Performance Analysis of an Energy Efficient Femtocell Network Using Queuing Theory

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    Wanod Kumar


    Full Text Available The energy expenditure of cellular networks is increasing rapidly due to high demand of data services by the subscribers. This subsequently gives rise to the CO2 emission which is a critical issue nowadays. A hybrid cellular network comprised of macrocell and several femtocells is required to achieve reliability, continuous connectivity, and energy efficiency. To address the issue of energy efficiency, in this paper we present a queuing model of an energy efficient femtocell network. The transmission of data traffic in this type of network is modeled using M/M/1 queue where server FAP (Femtocell Access Point takes vacation to save energy during inactivity period. The network model is solved using a MGM (Matrix Geometric Method. The performance of the system is evaluated in terms of average system delay and power savings for different sleep cycle durations. Results reveal that the maximum energy can be saved with higher sleep cycle duration at a cost of increased system delay

  17. A single-server Markovian queuing system with discouraged arrivals and retention of reneged customers

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    Kumar Rakesh


    Full Text Available Customer impatience has a very negative impact on the queuing system under investigation. If we talk from business point of view, the firms lose their potential customers due to customer impatience, which affects their business as a whole. If the firms employ certain customer retention strategies, then there are chances that a certain fraction of impatient customers can be retained in the queuing system. A reneged customer may be convinced to stay in the queuing system for his further service with some probability, say q and he may abandon the queue without receiving the service with a probability p(=1− q. A finite waiting space Markovian single-server queuing model with discouraged arrivals, reneging and retention of reneged customers is studied. The steady state solution of the model is derived iteratively. The measures of effectiveness of the queuing model are also obtained. Some important queuing models are derived as special cases of this model.

  18. modelling of queuing process at airport check-in system

    African Journals Online (AJOL)


    models in queue studies. The study adopted travel demand data for Manchester and Leeds-Bradford airports from the United Kingdom. Civil Aviation Authority database. 1.2 Analytical Models for Queuing Studies. Previous researchers have examined queuing process extensively and developed analytical models used for.

  19. Application of queuing theory in inventory systems with substitution flexibility (United States)

    Seyedhoseini, S. M.; Rashid, Reza; Kamalpour, Iman; Zangeneh, Erfan


    Considering the competition in today's business environment, tactical planning of a supply chain becomes more complex than before. In many multi-product inventory systems, substitution flexibility can improve profits. This paper aims to prepare a comprehensive substitution inventory model, where an inventory system with two substitute products with ignorable lead time has been considered, and effects of simultaneous ordering have been examined. In this paper, demands of customers for both of the products have been regarded as stochastic parameters, and queuing theory has been used to construct a mathematical model. The model has been coded by C++, and it has been analyzed due to a real example, where the results indicate efficiency of proposed model.


    Directory of Open Access Journals (Sweden)

    P. P. Oleynik


    Full Text Available The paper deals with domain-driven design applicability of information systems for client queuing subject areas. The following optimality criteria were put forward for the final implementation: the possibility of automation with a single system both for small institution and a whole network of institutions; advanced graphical interface with support for sensor screens; implementation of multi-users account of orders from clients; flexible application architecture with the ability of future enhancement; ability of integration with a variety of peripherals. The necessity of each criterion definition is shown. For implementability estimation, test information system was designed, automating the queuing system. Unified modeling language UML is used. Description of each class functionality is given and the association with other classes as well. Attention is paid to the design of tree (hierarchical structures and selection procedure of base classes based on the analysis of existing common attributes. For the system implementation, its own development environment SharpArchitect RAD Studio is used, offering MDA approach for implementation of systems based on standardized meta object system. A graphical view of order form developed prototype is presented, composition and structure are described, and notation developed by the author is given simplifying the prototyping process. Approaches to differentiation of access rights for different user roles are shown. Conformity of the received implementation to each selected optimality criterion is determined. Recommendations for further system development are given.


    Directory of Open Access Journals (Sweden)

    Rakesh Kumar


    Full Text Available In this paper, we study a catastrophic-cum-restorative queuing system with correlated batch arrivals and service in batches of variable sizes. We perform the transient analysis of the queuing model. We obtain the Laplace Transform of the probability generating function of system size. Finally, some particular cases of the model have been derived and discussed. Keywords: Queue length, Catastrophes, Correlated batch arrivals, Broadband services, Variable service capacity, and Restoration.

  2. Modeling and simulation of M/M/c queuing pharmacy system with adjustable parameters (United States)

    Rashida, A. R.; Fadzli, Mohammad; Ibrahim, Safwati; Goh, Siti Rohana


    This paper studies a discrete event simulation (DES) as a computer based modelling that imitates a real system of pharmacy unit. M/M/c queuing theo is used to model and analyse the characteristic of queuing system at the pharmacy unit of Hospital Tuanku Fauziah, Kangar in Perlis, Malaysia. The input of this model is based on statistical data collected for 20 working days in June 2014. Currently, patient waiting time of pharmacy unit is more than 15 minutes. The actual operation of the pharmacy unit is a mixed queuing server with M/M/2 queuing model where the pharmacist is referred as the server parameters. DES approach and ProModel simulation software is used to simulate the queuing model and to propose the improvement for queuing system at this pharmacy system. Waiting time for each server is analysed and found out that Counter 3 and 4 has the highest waiting time which is 16.98 and 16.73 minutes. Three scenarios; M/M/3, M/M/4 and M/M/5 are simulated and waiting time for actual queuing model and experimental queuing model are compared. The simulation results show that by adding the server (pharmacist), it will reduce patient waiting time to a reasonable improvement. Almost 50% average patient waiting time is reduced when one pharmacist is added to the counter. However, it is not necessary to fully utilize all counters because eventhough M/M/4 and M/M/5 produced more reduction in patient waiting time, but it is ineffective since Counter 5 is rarely used.

  3. The Application of Spreadsheet Model Based on Queuing Network to Optimize Capacity Utilization in Product Development


    Muhammad Marsudi; Dzuraidah Abdul Wahab; Che Hasan Che Haron


    Modeling of a manufacturing system enables one to identify the effects of key design parameters on the system performance and as a result make the correct decision. This paper proposes a manufacturing system modeling approach using computer spreadsheet software, in which a static capacity planning model and stochastic queuing model are integrated. The model was used to optimize the existing system utilization in relation to product design. The model incorporates a few parameters such as utili...

  4. Fuzzy Optimization and Normal Simulation for Solving Fuzzy Web Queuing System Problems

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    Xidong Zheng


    Full Text Available In this paper, we use both fuzzy optimization and normal simulation methods to solve fuzzy web planning model problems, which are queuing system problems for designing web servers. We apply fuzzy probabilities to the queuing system models with customers arrival rate l and servers?service rate m, and then compute fuzzy system performance variables, including Utilization, Number (of requests in the System, Throughput, and Response Time. For the fuzzy optimization method, we apply two-step calculation, first use fuzzy calculation to get the maximum and minimum values of fuzzy steady state probabilities, and then we compute the fuzzy system performance variables. For the simulation method, we use one-step normal queuing theory to simulate the whole system performance and its variables. We deal with queuing systems with a single server and multiple servers?cases, and compare the results of these two cases, giving a mathematical explanation of the difference. Keywords: Fuzzy Optimization, Normal Simulation, Queuing Theory, Web Planning Model.

  5. Improved Road-Network-Flow Control Strategy Based on Macroscopic Fundamental Diagrams and Queuing Length in Connected-Vehicle Network

    Directory of Open Access Journals (Sweden)

    Xiaohui Lin


    Full Text Available Connected-vehicles network provides opportunities and conditions for improving traffic signal control, and macroscopic fundamental diagrams (MFD can control the road network at the macrolevel effectively. This paper integrated proposed real-time access to the number of mobile vehicles and the maximum road queuing length in the Connected-vehicles network. Moreover, when implementing a simple control strategy to limit the boundary flow of a road network based on MFD, we determined whether the maximum queuing length of each boundary section exceeds the road-safety queuing length in real-time calculations and timely adjusted the road-network influx rate to avoid the overflow phenomenon in the boundary section. We established a road-network microtraffic simulation model in VISSIM software taking a district as the experimental area, determined MFD of the region based on the number of mobile vehicles, and weighted traffic volume of the road network. When the road network was tending to saturate, we implemented a simple control strategy and our algorithm limits the boundary flow. Finally, we compared the traffic signal control indicators with three strategies: (1 no control strategy, (2 boundary control, and (3 boundary control with limiting queue strategy. The results show that our proposed algorithm is better than the other two.

  6. Using multi-class queuing network to solve performance models of e-business sites. (United States)

    Zheng, Xiao-ying; Chen, De-ren


    Due to e-business's variety of customers with different navigational patterns and demands, multi-class queuing network is a natural performance model for it. The open multi-class queuing network(QN) models are based on the assumption that no service center is saturated as a result of the combined loads of all the classes. Several formulas are used to calculate performance measures, including throughput, residence time, queue length, response time and the average number of requests. The solution technique of closed multi-class QN models is an approximate mean value analysis algorithm (MVA) based on three key equations, because the exact algorithm needs huge time and space requirement. As mixed multi-class QN models, include some open and some closed classes, the open classes should be eliminated to create a closed multi-class QN so that the closed model algorithm can be applied. Some corresponding examples are given to show how to apply the algorithms mentioned in this article. These examples indicate that multi-class QN is a reasonably accurate model of e-business and can be solved efficiently.

  7. Modelling of queuing process at airport check-in system: a case ...

    African Journals Online (AJOL)

    This study built a Simulation Model (SM) using SimEvents toolbox in MATLAB for implementing Analytical Models (AM) of queuing process at airport check - in system. Air travel demand data for Manchester and Leeds - Bradford airports in 2014 were adopted for validation of the model. There was no statistical differenc e ...

  8. On a two-server finite queuing system with ordered entry and deterministic arrivals

    NARCIS (Netherlands)

    Nawijn, W.M.


    Consider a two-server, ordered entry, queuing system with heterogeneous servers and finite waiting rooms in front of the servers. Service times are negative exponentially distributed. The arrival process is deterministic. A matrix solution for the steady state probabilities of the number of

  9. M/M/1/N Queuing System with Retention of Reneged Customers

    Directory of Open Access Journals (Sweden)

    Rakesh Kumar


    Full Text Available The concept of customer reneging has been exploited to a great extent in recent past by the queuing modelers. Economically, if we see, the customer reneging leads to loss of potential customers and thereby results into the loss in the total revenue. Taking into consideration this customers’ loss due to reneging, a new queuing model has been developed that deals with customer retention. According to this model, a reneged customer can be convinced in many cases by employing certain convincing mechanism to stay in the queue for completion of his service. Thus, a reneged customer can be retained in the queuing system with some probability (say, q and it may leave the queue without receiving service with probability p (=1-q. This process is referred to as customer retention. We consider a single server, finite capacity queuing system with customer retention in which the inter-arrival and service times follow negative-exponential distribution. The reneging times are assumed to be exponentially distributed. The steady state solution of the model has been obtained. Some performance measures have been computed. The sensitivity analysis of the model has been carried out. The effect of probability of retention on the average system size has been studied. The numerical results show that the average system size increases steadily as the probability of retention increases. Some particular cases of the model have been derived and discussed.

  10. Preventing Out-of-Sequence for Multicast Input-Queued Space-Memory-Memory Clos-Network

    DEFF Research Database (Denmark)

    Yu, Hao; Ruepp, Sarah Renée; Berger, Michael Stübert


    This paper proposes an out-of-sequence (OOS) preventative cell dispatching algorithm, the multicast flow-based round robin (MFRR), for multicast input-queued space-memory-memory (IQ-SMM) Clos-network architecture. Independently treating each incoming cell, such as the desynchronized static round...

  11. Measurement of Mobile Switching Centres Throughput in GSM Network Integrating Sliding Window Algorithm with a Single Server Finite Queuing Model

    Directory of Open Access Journals (Sweden)

    Dinaker Babu Bollini


    Full Text Available The sliding window algorithm proposed for determining an optimal sliding window does not consider the waiting times of call setup requests of a mobile station in queue at a Mobile Switching Centre (MSC in the Global System for Mobile (GSM Communication Network. This study proposes a model integrating the sliding window algorithm with a single server finite queuing model, referred to as integrated model for measurement of realistic throughput of a MSC considering the waiting times of call setup requests. It assumes that a MSC can process one call setup request at a time. It is useful in determining an optimal sliding window size that maximizes the realistic throughput of a MSC. Though the model assumes that a MSC can process one call setup request at a time, its scope can be extended for measuring the realistic throughput of a MSC that can process multiple call setup requests at a time.

  12. A discrete event simulation model for evaluating the performances of an m/g/c/c state dependent queuing system.

    Directory of Open Access Journals (Sweden)

    Ruzelan Khalid

    Full Text Available M/G/C/C state dependent queuing networks consider service rates as a function of the number of residing entities (e.g., pedestrians, vehicles, and products. However, modeling such dynamic rates is not supported in modern Discrete Simulation System (DES software. We designed an approach to cater this limitation and used it to construct the M/G/C/C state-dependent queuing model in Arena software. Using the model, we have evaluated and analyzed the impacts of various arrival rates to the throughput, the blocking probability, the expected service time and the expected number of entities in a complex network topology. Results indicated that there is a range of arrival rates for each network where the simulation results fluctuate drastically across replications and this causes the simulation results and analytical results exhibit discrepancies. Detail results that show how tally the simulation results and the analytical results in both abstract and graphical forms and some scientific justifications for these have been documented and discussed.

  13. Impact of Queuing on Call Completion Rate in GSM Networks | Nkop ...

    African Journals Online (AJOL)

    In this paper, we use the queuing approach to develop a model for call completion, making signal power considerations as well. A General User Interface (GUI) is designed for the developed model using MATLAB and the impact of queuing on call completion is analysed by carrying out an assessment of the performance of ...

  14. Appoximation Formula for Estimation of Waiting-Time in Multiple-Channel Queuing Systems

    DEFF Research Database (Denmark)

    Maaløe, Erik


    The article deals with two approxiamation formulae for estimation of W, Waiting-times in a M/E/R queuing system.m First is shown how W for the multiple-channel system is approximately an Rth part of the mean waiting time in a single channel system. A second approximation applies the exact ratio...... for W(multi-channel/W(single channel) and M/M/1-systems to general M/Ek/R-systems. This is particularly illustrated in the case og M/M/R and M/D/R-systems as a general warning against general practices...

  15. Improved network convergence and quality of service by strict priority queuing of routing traffic (United States)

    Balandin, Sergey; Heiner, Andreas P.


    During the transient period after a link failure the network cannot guarantee the agreed service levels to user data. This is due to the fact that forwarding tables in the network are inconsistent. Moreover, link states can inadvertently be advertised wrong due to protocol time outs, which may result in persistent route flaps. Reducing the probability of wrongly advertised link states, and the time during which the forwarding tables are inconsistent, is therefore of eminent importance to provide consistent and high level QoS to user data. By queuing routing traffic in a queue with strict priority over all other (data) queues, i.e. assigning the highest priority in a Differentiated Services model, we were able to reduce the probability of routing data loss to almost zero, and reduce flooding times almost to their theoretical limit. The quality of service provided to user traffic was considerable higher than without the proposed modification. The scheme is independent of the routing protocol, and can be used with most differentiated service models. It is compatible with the current OSPF standard, and can be used in conjunction with other improvements in the protocol with similar objectives.

  16. Evacuation time estimate for a total pedestrian evacuation using queuing network model and volunteered geographic information

    CERN Document Server

    Kunwar, Bharat; Johansson, Anders


    Estimating city evacuation time is a non-trivial problem due to the interaction between thousands of individual agents, giving rise to various collective phenomena, such as bottleneck formation, intermittent flow and stop-and-go waves. We present a mean field approach to draw relationships between road network spatial attributes, number of evacuees and resultant evacuation time estimate (ETE). We divide $50$ medium sized UK cities into a total of $697$ catchment areas which we define as an area where all agents share the same nearest exit node. In these catchment areas, 90% of agents are within $5.4$ km of their designated exit node. We establish a characteristic flow rate from catchment area attributes (population, distance to exit node and exit node width) and a mean flow rate in free-flow regime by simulating total evacuations using an agent based `queuing network' model. We use these variables to determine a relationship between catchment area attributes and resultant ETE. This relationship could enable e...

  17. Modeling and simulation of queuing system for customer service improvement: A case study (United States)

    Xian, Tan Chai; Hong, Chai Weng; Hawari, Nurul Nazihah


    This study aims to develop a queuing model at UniMall by using discrete event simulation approach in analyzing the service performance that affects customer satisfaction. The performance measures that considered in this model are such as the average time in system, the total number of student served, the number of student in waiting queue, the waiting time in queue as well as the maximum length of buffer. ARENA simulation software is used to develop a simulation model and the output is analyzed. Based on the analysis of output, it is recommended that management of UniMall consider introducing shifts and adding another payment counter in the morning.

  18. Out-of-Sequence Preventative Cell Dispatching for Multicast Input-Queued Space-Memory-Memory Clos-Network

    DEFF Research Database (Denmark)

    Yu, Hao; Ruepp, Sarah Renée; Berger, Michael Stübert


    This paper proposes two out-of-sequence (OOS) preventative cell dispatching algorithms for the multicast input-queued space-memory-memory (IQ-SMM) Clos-network switch architecture, i.e. the multicast flow-based DSRR (MF-DSRR) and the multicast flow-based round-robin (MFRR). Treating each cell...... independently, the desynchronized static round-robin (DSRR) cell dispatching scheme can evenly distribute cells to the central switching modules, however, its frequent change of the input switching module connection pattern causes a serious OOS problem to the IQ-SMM architecture. Therefore large reassembly...

  19. Ship Lock as General Queuing System with Batch Arrivals and Batch Service

    Directory of Open Access Journals (Sweden)

    Zoran Radmilović


    Full Text Available The real lock operations with ships and barge convoys areconsidered dependent on the transport technologies applied, ormore precisely, the kinds of ships/convoys requiring thelockage. The fleet can be divided as follows: (1 groups of singleships, (2 pushed and pulled tows of barges and (3 differentcombinations of previous systems (1 and (2. The groups ofships and tows passing through the lock have extremely stochasticcharacteristics thus forming various arrivals and setvicetime patterns. It means that uniform navigation or strongscheduling between locks and lock operations are not possibleeven though highly sophisticated equipment is at disposal.Therefore, in this paper an analytical method was developedusing bulk queuing systems for the analysis and planning oflock requirements supporting it with numerical example. Thedeveloped methodology can be applied to determine the meanqueue length of ships - convoys at lock anchorage, withoutblocking behaviour between upstream and downstream navigationfor single-lane traffic.

  20. A tutorial on queuing and trunking with applications to communications

    CERN Document Server

    Tranter, William H


    The motivation for developing this synthesis lecture was to provide a tutorial on queuing and trunking, with extensions to networks of queues, suitable for supplementing courses in communications, stochastic processes, and networking. An essential component of this lecture is MATLAB-based demonstrations and exercises, which can be easily modified to enable the student to observe and evaluate the impact of changing parameters, arrival and departure statistics, queuing disciplines, the number of servers, and other important aspects of the underlying system model. Much of the work in this lecture

  1. Modeling a heterogeneous network with TCP connections using fluid flow approximation and queuing theory (United States)

    Hisamatu, Hiroyuki; Ohsaki, Hiroyuki; Murata, Masayuki


    In the current Internet, most of the traffic is transmitted by TCP (Transmission Control Protocol). In our previous work, we have proposed a modeling approach for the entire network, including TCP congestion control mechanisms operating at source hosts and the network seen by TCP connections, as a single feedback system. However, our analytic model is limited to a simple network, where TCP connections have the identical propagation delay. In this paper, we therefore extend our analytic approach to a more generic network, where multiple TCP connections are allowed to have different propagation delays. We derive the packet loss probability in the network, the throughput and the average round-trip time of each TCP connection in steady state. By presenting several numerical examples, we quantitatively investigate how the fairness among TCP connections is degraded when multiple TCP connections with different propagation delays share the single bottleneck link.

  2. A novel approach for optimization in a fuzzy finite capacity queuing model with system cost and expected degree of customer satisfaction

    Directory of Open Access Journals (Sweden)

    Mohammad Bagher Shahin


    Full Text Available From a wide variety of queuing models, the finite-capacity queuing models are the most commonly used, where arrival and service rates follow an exponential distribution. Based on two criteria of system cost and expected degree of customer satisfaction, the present study defines a new productivity rate index and evaluates the optimization of a queuing model with finite capacity. In queuing models, obviously, as the number of servers increases, the length of waiting lines decreases, the expected degree of customer satisfaction enhances, and obviously the system cost increases. This study deals with the mathematical relationships involved in the computations of these two criteria, and proposes a novel approach to determine an optimal number of servers by considering a decision-maker's priority and establishing a trade-off between criteria.

  3. Non-Stationary Single-Channel Queuing System Features Research in Context of Number of Served Queries

    Directory of Open Access Journals (Sweden)

    Porshnev Sergey


    Full Text Available This work devoted to researching of mathematical model of non-stationary queuing system (NQS. Arrival rate in studied NQS λ(t is similar to rate which observed in practice in a real access control system of objects of mass events. Dependence of number of serviced requests from time was calculated. It is proven that the ratio value of served requests at the beginning of event to all served requests described by a deterministic function, depending on the average service rate μ¯$\\bar \\mu $ and the maximum value of the arrival rate function λ(t.

  4. Modeling of Multihop Wireless Sensor Networks with MAC, Queuing, and Cooperation


    Jian Lin; Mary Ann Weitnauer


    We present a Markovian decision process (MDP) framework for multihop wireless sensor networks (MHWSNs) to bound the network performance of both energy constrained (EC) networks and energy harvesting (EH) networks, both with and without relay cooperation. The model provides the fundamental performance limit that a MHWSN can theoretically achieve, under the general constraints from medium access control, routing, and energy harvesting. We observe that the analyses for EC and EH networks fall in...

  5. Modeling and Analysis of Queuing Systems in Banks A case study of Ghana Commercial Bank Ltd. Kumasi Main Branch

    Directory of Open Access Journals (Sweden)

    Wallace Agyei


    Full Text Available Abstract Queues are common sight of many banks in Ghana. The obvious implication of customers waiting in long and winding queues could result to prolonged discomfort and economic cost to them however increasing the service rate will require additional number of tellers which implies extra cost to management. This study therefore attempts to find the trade-off between minimizing the total economic cost waiting cost and service cost and the provision of a satisfactory and reasonably shortest possible time of service to customers in order to assist management of the bank in deciding the optimal number of tellers needed. Data for this study was collected at the Ghana Commercial Bank Ltd Kumasi Main Branch for one month through observations interviews and by administering of questionnaire and was formulated as multi-server single line queuing model. The data was analyzed using TORA optimization Software as well as using descriptive method of analysis. The performance measures of different queuing systems were evaluated and analyzed. The results of the analysis showed using a five teller system was better than a four or a six-teller system in terms of average waiting time and thetotal economic cost hence the study recommends that the management should adopt a five teller model to reduce total economic costs and increase customer satisfaction.

  6. Queuing Rule of Thumb based on M/M/s Queuing Theory with Applications in Construction Management

    Directory of Open Access Journals (Sweden)

    Teknomo K.


    Full Text Available The current trend of queuing theory development is toward more precision which requires higher mathematical manipulation. In this paper, we attempted to reverve the current trend toward simplification of queuing formulas such that it can be used in more practical purposes, especially in construction industry. Through numerical examples of two case studies on concreting and earth moving, how to model the construction activities as queuing systems is illustrated systematically. Through the numerical examples, it is shown that when the customer cost is much lower than the server cost, queuing system can be simplified only to incorporate the constraint equation. The queueing constraint equation is suggested to be used as queuing rule of thumb. The proposed rule of thumb is rather conservative in term of queuing performance compared to the standard stochastic queuing formula because it is assumed that all the customers arrive at once in the beginning of the service.

  7. Out-of-Sequence Prevention for Multicast Input-Queuing Space-Memory-Memory Clos-Network

    DEFF Research Database (Denmark)

    Yu, Hao; Ruepp, Sarah; Berger, Michael Stübert


    This paper proposes two cell dispatching algorithms for the input-queuing space-memory-memory (IQ-SMM) Closnetwork to reduce out-of-sequence (OOS) for multicast traffic. The frequent connection pattern change of DSRR results in a severe OOS problem. Based on the principle of DSRR, MFDSRR is able...

  8. Energy Consumption Evaluation for Wireless Sensor Network Nodes Based on Queuing Petri Net


    Li, J.; Zhou, H. Y.; D. C. Zuo; Hou, K. M.; Xie, H. P.; Zhou, P.


    Due to the large scale of wireless sensor networks (WSN) and the huge density of WSN nodes, classical performance evaluation techniques face new challenges in view of the complexity and diversity in WSN applications. This paper presents a “state-event-transition” formal description for WSN nodes and proposes an event-driven QPN-based modeling technique to simulate the energy behaviors of nodes. Besides, the framework architecture of a dedicated energy evaluation platform has been introduced, ...

  9. Principles of Queued Service Observing at CFHT (United States)

    Manset, Nadine; Burdullis, T.; Devost, D.


    CFHT started to use Queued Service Observing in 2001, and is now operating in that mode over 95% of the time. Ten years later, the observations are now carried out by Remote Observers who are not present at the telescope (see the companion presentation "Remote Queued Service Observing at CFHT"). The next phase at CFHT will likley involve assisted or autonomous service observing (see the presentation "Artificial Intelligence in Autonomous Telescopes"), which would not be possible without first having a Queued observations system already in place. The advantages and disadvantages of QSO at CFHT will be reviewed. The principles of QSO at CFHT, which allow CFHT to complete 90-100% of the top 30-40% programs and often up to 80% of other accepted programs, will be presented, along with the strategic use of overfill programs, the method of agency balance, and the suite of planning, scheduling, analysis and data quality assessment tools available to Queue Coordinators and Remote Observers.

  10. Bidirectional multi-optical line terminals incorporated converged WSN-PON network using M/M/1 queuing (United States)

    Kumar, Love; Sharma, Vishal; Singh, Amarpal


    Wireless Sensor Networks (WSNs) have an assortment of application areas, for instance, civil, military, and video surveillance with restricted power resources and transmission link. To accommodate the massive traffic load in hefty sensor networks is another key issue. Subsequently, there is a necessity to backhaul the sensed information of such networks and prolong the transmission link to access the distinct receivers. Passive Optical Network (PON), a next-generation access technology, comes out as a suitable candidate for the convergence of the sensed data to the core system. The earlier demonstrated work with single-OLT-PON introduces an overloaded buffer akin to video surveillance scenarios. In this paper, to combine the bandwidth potential of PONs with the mobility capability of WSNs, the viability for the convergence of PONs and WSNs incorporating multi-optical line terminals is demonstrated to handle the overloaded OLTs. The existing M/M/1 queue theory with interleaving polling with adaptive cycle time as dynamic bandwidth algorithm is used to shun the probability of packets clash. Further, the proposed multi-sink WSN and multi-OLT PON converged structure is investigated in bidirectional mode analytically and through computer simulations. The observations establish the proposed structure competent to accommodate the colossal data traffic through less time consumption.

  11. A Literature Study on Dynamic Bandwidth Allocation Mechanisms for Tandem Communication Networks

    Directory of Open Access Journals (Sweden)



    Full Text Available Modeling and performance prediction are becoming increasingly important issues in the design and operation of computer communications systems. In this paper a review is carried out on how Tandem queuing models with Dynamic Bandwidth Allocation have been applied so far into the performance evaluation of Communication Networks. Queuing network models with finite/infinite capacity buffers and blocking have been applied as more realistic models of systems with finite capacity resources. First we review basic properties of exponential queuing systems, and then give an overview of recent progress made in the areas of dynamic bandwidth allocation for tandem queuing network models and performance measures.

  12. An Application of the Queuing Theory

    African Journals Online (AJOL)

    The study therefore recommends that the management of the bank considers adding an extra service point as this is a significant improvement over the current system, particularly in terms of the time spent by customers waiting in line to be served. Key words: Queuing theory, customers, competition, time, service point ...

  13. A Queuing Model-Based System for Triggering Traffic Flow Management Algorithms Project (United States)

    National Aeronautics and Space Administration — Next generation air traffic management systems are expected use multiple software tools and quantitative methods for managing traffic flow in the National Airspace....

  14. Stochastic extension of cellular manufacturing systems: a queuing-based analysis (United States)

    Fardis, Fatemeh; Zandi, Afagh; Ghezavati, Vahidreza


    Clustering parts and machines into part families and machine cells is a major decision in the design of cellular manufacturing systems which is defined as cell formation. This paper presents a non-linear mixed integer programming model to design cellular manufacturing systems which assumes that the arrival rate of parts into cells and machine service rate are stochastic parameters and described by exponential distribution. Uncertain situations may create a queue behind each machine; therefore, we will consider the average waiting time of parts behind each machine in order to have an efficient system. The objective function will minimize summation of idleness cost of machines, sub-contracting cost for exceptional parts, non-utilizing machine cost, and holding cost of parts in the cells. Finally, the linearized model will be solved by the Cplex solver of GAMS, and sensitivity analysis will be performed to illustrate the effectiveness of the parameters.

  15. First passage processes in Queuing system MX/Gr/1 with service delay discipline

    Directory of Open Access Journals (Sweden)

    Lev Abolnikov


    Full Text Available This article deals with a general single-server bulk queueing system with a server waiting until the queue will reach level r before it starts processing customers. If at least r customers are available the server takes a batch of the fixed size r of units for service. The input stream is assumed to be a compound Poisson process modulated by a semi-Markov process and with a multilevel control of service time.

  16. Feature analysis for closed queuing system with non-preemptive priorities

    Directory of Open Access Journals (Sweden)

    Yu. G. Nesterov


    Full Text Available The object of research in this article is to obtain the analytical expressions for the probability distribution functions (PDF of states of the closed system of mass service (SMS like "model of the repairman" Mr|GIr|1 || Nr in a stationary mode. The SMS has a source of requests of final capacity with exponentially distributed time of residence of different class requests in the source, one queue with discipline of requests service i.e. the non-preemptive priorities, one serving device (SD and arbitrary PDF of a residence time of each class requests.The method includes the following steps.The first step, while servicing the non-uniform population of requests, distinguishes a sequence of time points, so-called points of regeneration in which a process behaves as Markov's. It is shown that such points are time points to complete a service of requests in SD. Further, for these points an embedded Markov's chain is designed, and the states space of this chain is defined. Analytical expressions to calculate the elements of transition probability matrix in such chain are obtained. These expressions reflect a relationship between these probabilities and the source parameters, the residence time PDF parameters, the number of each class requests, and a discipline of their service. Further, the solution for PDF of this chain states is found.The second step establishes connection between the PDF of SMS states in a stationary mode and the previously received PDF of states of the embedded Markov's chain. Such connection is defined by a system of the equations of global balance for the SMS states in a stationary mode and states of the embedded Markov's chain. The physical sense of such balance is that each of SMS state in a stationary mode is in equilibrium, i.e. the intensities of transitions from the state and in the state are equal. The space of states of initial SMS in a stationary mode is defined. It is shown that in intervals of request service time in SD

  17. Implementacija metode automatizovanih nezavisnih ponavljanja u simulaciji sistema masovnog opsluživanja / Implementation of automated independent replications in the simulation of queuing systems

    Directory of Open Access Journals (Sweden)

    Nebojša V. Nikolić


    Full Text Available U radu je opisana osnovna ideja metode pod nazivom 'Automatizovano ponavljanje nezavisnih simulacionih eksperimenata sa prikupljanjem statistike slučajnih procesa'. Data je matematička osnova metode i prikazane su preporuke za implementaciju metode u formu algoritma za računarski program. Pregledno su istaknuta potrebna ekspertska znanja za uspešan razvoj konceptualnih i simulacionih modela. Metoda je testirana u istraživanju sistema masovnog opsluživanja. / This paper presents a basic idea of the method entitled 'Automated Independent Replications with Gathering Statistics of Stochastic Processes'. The mathematical foundation of the method is offered, as well as some recommendations for practical implementation of the met hod in the form of a computer program algorithm. A set of different expert knowledge needed for a successful development of conceptual and simulation models is pointed out in a separate review. The method has been tested in the modeling and simulation of queuing systems. Multidisciplinary character of simulation modeling This paper presents a basic idea of the method entitled 'Automated Independent Replications with Gathering Statistics of Stochastic Processes'. A clear review of expert knowledge needed for successful development of a conceptual model as well as a simulation one is offered. Simulation modeling of systems and processes in any military branch assumes a multidisciplinary approach. This is not a consequence of a free choice, but of needs and problems which arise in a research process and which require synchronized use of knowledge from different areas and scientific disciplines. In studies of queuing systems, these disciplines are: queuing theory, probability theory, mathematical statistics, stochastic processes, mathematical analyses, Monte Carlo simulation modeling, computer programming, knowledge about a real system under study, etc. Specific features of real queuing systems Consistency, fidelity or

  18. On a Batch Arrival Queuing System Equipped with a Stand-by Server during Vacation Periods or the Repairs Times of the Main Server

    Directory of Open Access Journals (Sweden)

    Rehab F. Khalaf


    Full Text Available We study a queuing system which is equipped with a stand-by server in addition to the main server. The stand-by server provides service to customers only during the period of absence of the main server when either the main server is on a vacation or it is in the state of repairs due to a sudden failure from time to time. The service times, vacation times, and repair times are assumed to follow general arbitrary distributions while the stand-by service times follow exponential distribution. Supplementary variables technique has been used to obtain steady state results in explicit and closed form in terms of the probability generating functions for the number of customers in the queue, the average number of customers, and the average waiting time in the queue while the MathCad software has been used to illustrate the numerical results in this work.

  19. Performance Approximation and Design of Pick-and-Pass Order Picking Systems

    NARCIS (Netherlands)

    M. Yu (Mengfei); M.B.M. de Koster (René)


    textabstractIn this paper, we discuss an approximation method based on G/G/m queuing network modeling using Whitt’s (1983) queuing network analyzer to analyze pick-and-pass order picking systems. The objective of this approximation method is to provide an instrument for obtaining rapid performance

  20. A note on the optimal pricing strategy in the discrete-time Geo/Geo/1 queuing system with sojourn time-dependent reward

    Directory of Open Access Journals (Sweden)

    Doo Ho Lee

    Full Text Available This work studies the optimal pricing strategy in a discrete-time Geo/Geo/1 queuing system under the sojourn time-dependent reward. We consider two types of pricing schemes. The first one is called the ex-post payment scheme where the server charges a price that is proportional to the time a customer spends in the system, and the second one is called ex-ante payment scheme where the server charges a flat price for all services. In each pricing scheme, a departing customer receives the reward that is inversely proportional to his/her sojourn time. The server should make the optimal pricing decisions in order to maximize its expected profits per time unit in each pricing scheme. This work also investigates customer's equilibrium joining or balking behavior under server's optimal pricing strategy. Numerical experiments are also conducted to validate our analysis. Keywords: Optimal pricing, Equilibrium behavior, Geo/Geo/1 queue, Sojourn time-dependent reward

  1. Application of queuing theory in production-inventory optimization (United States)

    Rashid, Reza; Hoseini, Seyed Farzad; Gholamian, M. R.; Feizabadi, Mohammad


    This paper presents a mathematical model for an inventory control system in which customers' demands and suppliers' service time are considered as stochastic parameters. The proposed problem is solved through queuing theory for a single item. In this case, transitional probabilities are calculated in steady state. Afterward, the model is extended to the case of multi-item inventory systems. Then, to deal with the complexity of this problem, a new heuristic algorithm is developed. Finally, the presented bi-level inventory-queuing model is implemented as a case study in Electroestil Company.

  2. Application of queuing theory to patient satisfaction at a tertiary ...

    African Journals Online (AJOL)

    Background: Queuing theory is the mathematical approach to the analysis of waiting lines in any setting where arrival rate of subjects is faster than the system can handle. It is applicable to healthcare settings where the systems have excess capacity to accommodate random variations. Materials and Methods: A ...

  3. Stochastic Prediction and Feedback Control of Router Queue Size in a Virtual Network Environment (United States)


    OPNET model of the simple queuing system had used [3]. Client ServerRouter Figure 3.8: 1 router network topology 2 Routers Network...traffic demand with the inclusion of real operating systems and applications versus application models provided by discrete-event modeling and...2.1 Network Queues The mathematical study of queues or waiting lines is referred to as queuing theory. It consist of models constructed with the aim

  4. Design of an IPTV Multicast System for Internet Backbone Networks

    Directory of Open Access Journals (Sweden)

    T. H. Szymanski


    Full Text Available The design of an IPTV multicast system for the Internet backbone network is presented and explored through extensive simulations. In the proposed system, a resource reservation algorithm such as RSVP, IntServ, or DiffServ is used to reserve resources (i.e., bandwidth and buffer space in each router in an IP multicast tree. Each router uses an Input-Queued, Output-Queued, or Crosspoint-Queued switch architecture with unity speedup. A recently proposed Recursive Fair Stochastic Matrix Decomposition algorithm used to compute near-perfect transmission schedules for each IP router. The IPTV traffic is shaped at the sources using Application-Specific Token Bucker Traffic Shapers, to limit the burstiness of incoming network traffic. The IPTV traffic is shaped at the destinations using Application-Specific Playback Queues, to remove residual network jitter and reconstruct the original bursty IPTV video streams at each destination. All IPTV traffic flows are regenerated at the destinations with essentially zero delay jitter and essentially-perfect QoS. The destination nodes deliver the IPTV streams to the ultimate end users using the same IPTV multicast system over a regional Metropolitan Area Network. It is shown that all IPTV traffic is delivered with essentially-perfect end-to-end QoS, with deterministic bounds on the maximum delay and jitter on each video frame. Detailed simulations of an IPTV distribution system, multicasting several hundred high-definition IPTV video streams over several essentially saturated IP backbone networks are presented.

  5. Queuing Time Prediction Using WiFi Positioning Data in an Indoor Scenario. (United States)

    Shu, Hua; Song, Ci; Pei, Tao; Xu, Lianming; Ou, Yang; Zhang, Libin; Li, Tao


    Queuing is common in urban public places. Automatically monitoring and predicting queuing time can not only help individuals to reduce their wait time and alleviate anxiety but also help managers to allocate resources more efficiently and enhance their ability to address emergencies. This paper proposes a novel method to estimate and predict queuing time in indoor environments based on WiFi positioning data. First, we use a series of parameters to identify the trajectories that can be used as representatives of queuing time. Next, we divide the day into equal time slices and estimate individuals' average queuing time during specific time slices. Finally, we build a nonstandard autoregressive (NAR) model trained using the previous day's WiFi estimation results and actual queuing time to predict the queuing time in the upcoming time slice. A case study comparing two other time series analysis models shows that the NAR model has better precision. Random topological errors caused by the drift phenomenon of WiFi positioning technology (locations determined by a WiFi positioning system may drift accidently) and systematic topological errors caused by the positioning system are the main factors that affect the estimation precision. Therefore, we optimize the deployment strategy during the positioning system deployment phase and propose a drift ratio parameter pertaining to the trajectory screening phase to alleviate the impact of topological errors and improve estimates. The WiFi positioning data from an eight-day case study conducted at the T3-C entrance of Beijing Capital International Airport show that the mean absolute estimation error is 147 s, which is approximately 26.92% of the actual queuing time. For predictions using the NAR model, the proportion is approximately 27.49%. The theoretical predictions and the empirical case study indicate that the NAR model is an effective method to estimate and predict queuing time in indoor public areas.

  6. System design document for the INFLO prototype. (United States)


    This report documents the high level System Design Document (SDD) for the prototype development and : demonstration of the Intelligent Network Flow Optimization (INFLO) application bundle, with a focus on the Speed : Harmonization (SPD-HARM) and Queu...

  7. Queuing systems on a circle


    Kroese, Dirk; Schmidt, Volker


    Consider a ring on which customers arrive according to a Poisson process. Arriving customers drop somewhere on the circle and wait there for a server who travels on the ring. Whenever this server encounters a customer, he stops and serves the customer according to an arbitrary service time distribution. After the service is completed, the server removes the client from the circle and resumes his journey. We are interested in the number and the locations of customers that are waiting for servi...

  8. Queuing systems on a circle

    NARCIS (Netherlands)

    Kroese, Dirk; Schmidt, Volker


    Consider a ring on which customers arrive according to a Poisson process. Arriving customers drop somewhere on the circle and wait there for a server who travels on the ring. Whenever this server encounters a customer, he stops and serves the customer according to an arbitrary service time


    Directory of Open Access Journals (Sweden)

    Banihan GÜNAY


    Full Text Available The concept of road networks and traffic flow equilibrium conditions are briefly reviewed and discussed. In order to see whether some benefits for the society (e.g. whole network by employing a System Optimum assignment approach can be achieved or not, an assessment study was carried out on the Ystanbul road network using the actual data gathered. As a result of the system optimising simulation, queuing times on the Bosphorus Bridge dropped by 12% and speed of an average car increased by 16%, compared to the results produced by the User Equilibrium assignment. Besides, the total system journey time was also reduced by about 4%.

  10. Queuing Rule of Thumb based on M/M/s Queuing Theory with Applications in Construction Management

    National Research Council Canada - National Science Library

    Teknomo K


    .... The queueing constraint equation is suggested to be used as queuing rule of thumb. The proposed rule of thumb is rather conservative in term of queuing performance compared to the standard stochastic queuing formula because it is assumed that all the customers arrive at once in the beginning of the service.

  11. Performance Analysis of Heterogeneous Data Centers in Cloud Computing Using a Complex Queuing Model

    Directory of Open Access Journals (Sweden)

    Wei-Hua Bai


    Full Text Available Performance evaluation of modern cloud data centers has attracted considerable research attention among both cloud providers and cloud customers. In this paper, we investigate the heterogeneity of modern data centers and the service process used in these heterogeneous data centers. Using queuing theory, we construct a complex queuing model composed of two concatenated queuing systems and present this as an analytical model for evaluating the performance of heterogeneous data centers. Based on this complex queuing model, we analyze the mean response time, the mean waiting time, and other important performance indicators. We also conduct simulation experiments to confirm the validity of the complex queuing model. We further conduct numerical experiments to demonstrate that the traffic intensity (or utilization of each execution server, as well as the configuration of server clusters, in a heterogeneous data center will impact the performance of the system. Our results indicate that our analytical model is effective in accurately estimating the performance of the heterogeneous data center.

  12. Improving queuing service at McDonald's (United States)

    Koh, Hock Lye; Teh, Su Yean; Wong, Chin Keat; Lim, Hooi Kie; Migin, Melissa W.


    Fast food restaurants are popular among price-sensitive youths and working adults who value the conducive environment and convenient services. McDonald's chains of restaurants promote their sales during lunch hours by offering package meals which are perceived to be inexpensive. These promotional lunch meals attract good response, resulting in occasional long queues and inconvenient waiting times. A study is conducted to monitor the distribution of waiting time, queue length, customer arrival and departure patterns at a McDonald's restaurant located in Kuala Lumpur. A customer survey is conducted to gauge customers' satisfaction regarding waiting time and queue length. An android app named Que is developed to perform onsite queuing analysis and report key performance indices. The queuing theory in Que is based upon the concept of Poisson distribution. In this paper, Que is utilized to perform queuing analysis at this McDonald's restaurant with the aim of improving customer service, with particular reference to reducing queuing time and shortening queue length. Some results will be presented.

  13. Analysis of effectiveness of possible queuing models at gas stations using the large-scale queuing theory

    Directory of Open Access Journals (Sweden)

    Slaviša M. Ilić


    Full Text Available This paper analyzes the effectiveness of possible models for queuing at gas stations, using a mathematical model of the large-scale queuing theory. Based on actual data collected and the statistical analysis of the expected intensity of vehicle arrivals and queuing at gas stations, the mathematical modeling of the real process of queuing was carried out and certain parameters quantified, in terms of perception of the weaknesses of the existing models and the possible benefits of an automated queuing model.



    Hala Abbas Laz*, Mohamed Gomma Elnour


    The paper is studying the renewal process. There are many fields in which it’s used for example: the renewable energy (solar energy, wind energy), maintenance and replacement decision models, queuing system and other field in electronics. In this study our objective is to find the probability density function related to a renewal at a given time. Also to drive the renewal equation, how to find the current lifetime and residual life time. We obtain that as expected value of a renewal process w...

  15. A Queuing Approach for Energy Supply in Manufacturing Facilities


    Zavanella, Lucio; Ferretti, Ivan; Zanoni, Simone; Bettoni, Laura


    Part 1: Sustainable Production; International audience; Nowadays increasing energy efficiency is one of the main objectives of manufacturing systems so as to remain competitive despite of the foreseen increase in energy prices for the next years. We propose a novel queuing-based model for the appreciation of the energy consumption on a company base, so as to optimize the total energy costs due to electricity utilization.We propose an analytical model based on the extension of the M[x]/M/∞ mod...

  16. impact of queuing on call c queuing on call c queuing on call ...

    African Journals Online (AJOL)


    work resource reduces the probability that a call arriving at the base sta formance evaluation plays an important role in modelling and network resource. network resource. This objective is achieved by an accurate traffic characte. This objective is achieved by an accurate traffic characte rformance metrics in terms of traffic ...

  17. Computer network defense system (United States)

    Urias, Vincent; Stout, William M. S.; Loverro, Caleb


    A method and apparatus for protecting virtual machines. A computer system creates a copy of a group of the virtual machines in an operating network in a deception network to form a group of cloned virtual machines in the deception network when the group of the virtual machines is accessed by an adversary. The computer system creates an emulation of components from the operating network in the deception network. The components are accessible by the group of the cloned virtual machines as if the group of the cloned virtual machines was in the operating network. The computer system moves network connections for the group of the virtual machines in the operating network used by the adversary from the group of the virtual machines in the operating network to the group of the cloned virtual machines, enabling protecting the group of the virtual machines from actions performed by the adversary.

  18. Modelo hipercubo integrado a um algoritmo genético para análise de sistemas médicos emergenciais em rodovias The hypercube queuing model integrated to a genetic algorithm to analyze emergency medical systems on highways

    Directory of Open Access Journals (Sweden)

    Ana Paula Iannoni


    Full Text Available O modelo hipercubo, conhecido na literatura de problemas de localização de sistemas servidor para cliente, é um modelo baseado em teoria de filas espacialmente distribuídas e aproximações Markovianas. O modelo pode ser modificado para analisar os sistemas de atendimentos emergenciais (SAEs em rodovias, considerando as particularidades da política de despacho destes sistemas. Neste estudo, combinou-se o modelo hipercubo com um algoritmo genético para otimizar a configuração e operação de SAEs em rodovias. A abordagem é efetiva para apoiar decisões relacionadas ao planejamento e operação destes sistemas, por exemplo, em determinar o tamanho ideal para as áreas de cobertura de cada ambulância, de forma a minimizar o tempo médio de resposta aos usuários e o desbalanceamento das cargas de trabalho das ambulâncias. Os resultados computacionais desta abordagem foram analisados utilizando dados reais do sistema Anjos do Asfalto (rodovia Presidente Dutra.The hypercube model, well-known in the literature on problems of server-to-customer localization systems, is based on the spatially distributed queuing theory and Markovian analysis approximations. The model can be modified to analyze Emergency Medical Systems (EMSs on highways, considering the particularities of these systems' dispatching policies. In this study, we combine the hypercube model with a genetic algorithm to optimize the configuration and operation of EMSs on highways. This approach is effective to support planning and operation decisions, such as determining the ideal size of the area each ambulance should cover to minimize not only the average time of response to the user but also ambulance workload imbalances, as well as generating a Pareto efficient boundary between these measures. The computational results of this approach were analyzed using real data Anjos do Asfalto EMS (which covers the Presidente Dutra highway.

  19. Understanding the queuing theory for improved service delivery: an ...

    African Journals Online (AJOL)

    Queuing theory plays a huge role in solving and preventing operational bottlenecks and service failures in the organization. But, observations show that Queuing analysis may become extremely complex and cumbersome. Therefore, most entrepreneurs, having realized its usefulness in managing their much earned ...

  20. Network operating system (United States)


    Long-term and short-term objectives for the development of a network operating system for the Space Station are stated. The short-term objective is to develop a prototype network operating system for a 100 megabit/second fiber optic data bus. The long-term objective is to establish guidelines for writing a detailed specification for a Space Station network operating system. Major milestones are noted. Information is given in outline form.

  1. Queuing model of a traffic bottleneck with bimodal arrival rate (United States)

    Woelki, Marko


    This paper revisits the problem of tuning the density in a traffic bottleneck by reduction of the arrival rate when the queue length exceeds a certain threshold, studied recently for variants of totally asymmetric simple exclusion process (TASEP) and Burgers equation. In the present approach, a simple finite queuing system is considered and its contrasting “phase diagram” is derived. One can observe one jammed region, one low-density region and one region where the queue length is equilibrated around the threshold. Despite the simplicity of the model the physics is in accordance with the previous approach: The density is tuned at the threshold if the exit rate lies in between the two arrival rates.

  2. Application of queuing theory in banking services

    Directory of Open Access Journals (Sweden)

    Vitor Costa de Lima


    Full Text Available Bearing in mind the intense competition in the current economy and the increasing necessity of having more customers and keeping them loyal, this paper aims to apply the well known Queuing Theory in a bank agency to identify improvement opportunities in customer waiting time, from the assumption that the analyzed lines follow the Poisson’s distribution. This assumption results from the comparison between such distribution to the customers' arrival data in all analyzed lines. It was also found that there are queues with seasonality in demand, while others showed a regular demand. From the study performed, improvements in the management of this bank agency may be made, for example, the reallocation of staff in certain periods for functions with higher demand. It was concluded, therefore, that the application of the theory is feasible and can help to increase the competitive advantages of the agency.





    The theory of queues is a field of operational research within the scope of the theory of stochastic processes. The primary objective of this theory is to develop methods that allow determination of the basic indicators characterizing the process of handling and evaluation of the work quality of the queuing system and the choice of optimal structure and organization of the service. The purpose of this article is to show the application of the queuing theory to modelling the selected structure...

  4. Streams of events and performance of queuing systems: The basic anatomy of arrival/departure processes, when the focus is set on autocorrelation

    DEFF Research Database (Denmark)

    Nielsen, Erland Hejn


    situation or at least a very sound approximation. However, on the other hand, most actual decision making is based upon information taken from the past - where else! In fact the only real alternative that comes into my mind is to let a pair of dices fully and completely rule behaviour, but I wonder...... significant nature or (2) aggregate system behaviour is in general very different from just the summing-up (even for finite sets of micro-behavioural patterns) and/or (3) it is simply a wrong assumption that in many cases is chosen by mere convention or plain convenience. It is evident that before choosing...

  5. Triangulation positioning system network

    Directory of Open Access Journals (Sweden)

    Sfendourakis Marios


    Full Text Available This paper presents ongoing work on localization and positioning through triangulation procedure for a Fixed Sensors Network - FSN.The FSN has to work as a system.As the triangulation problem becomes high complicated in a case with large numbers of sensors and transmitters, an adequate grid topology is needed in order to tackle the detection complexity.For that reason a Network grid topology is presented and areas that are problematic and need further analysis are analyzed.The Network System in order to deal with problems of saturation and False Triangulations - FTRNs will have to find adequate methods in every sub-area of the Area Of Interest - AOI.Also, concepts like Sensor blindness and overall Network blindness, are presented. All these concepts affect the Network detection rate and its performance and ought to be considered in a way that the network overall performance won’t be degraded.Network performance should be monitored contentiously, with right algorithms and methods.It is also shown that as the number of TRNs and FTRNs is increased Detection Complexity - DC is increased.It is hoped that with further research all the characteristics of a triangulation system network for positioning will be gained and the system will be able to perform autonomously with a high detection rate.

  6. User Utility Oriented Queuing Model for Resource Allocation in Cloud Environment

    Directory of Open Access Journals (Sweden)

    Zhe Zhang


    Full Text Available Resource allocation is one of the most important research topics in servers. In the cloud environment, there are massive hardware resources of different kinds, and many kinds of services are usually run on virtual machines of the cloud server. In addition, cloud environment is commercialized, and economical factor should also be considered. In order to deal with commercialization and virtualization of cloud environment, we proposed a user utility oriented queuing model for task scheduling. Firstly, we modeled task scheduling in cloud environment as an M/M/1 queuing system. Secondly, we classified the utility into time utility and cost utility and built a linear programming model to maximize total utility for both of them. Finally, we proposed a utility oriented algorithm to maximize the total utility. Massive experiments validate the effectiveness of our proposed model.

  7. Network systems security analysis (United States)

    Yilmaz, Ä.°smail


    Network Systems Security Analysis has utmost importance in today's world. Many companies, like banks which give priority to data management, test their own data security systems with "Penetration Tests" by time to time. In this context, companies must also test their own network/server systems and take precautions, as the data security draws attention. Based on this idea, the study cyber-attacks are researched throughoutly and Penetration Test technics are examined. With these information on, classification is made for the cyber-attacks and later network systems' security is tested systematically. After the testing period, all data is reported and filed for future reference. Consequently, it is found out that human beings are the weakest circle of the chain and simple mistakes may unintentionally cause huge problems. Thus, it is clear that some precautions must be taken to avoid such threats like updating the security software.

  8. The Optimization of the Resources Allocation of Library ’s RFID System Based on Queuing Theory%基于排队论的图书馆RFID系统的资源配置优化

    Institute of Scientific and Technical Information of China (English)



    Through calculating readers’ queuing time, average waiting time and other parameters, and under the principle of ensuring the supremacy of reader service, the queuing theory model is applied into the modern library that has Introduced the FRID, which can save money, maximize the utilization of equipment, and more pontifically and more rationally optimize the resources allocation of modern library that has introduced FRID technique.%通过对读者排队时间及平均等待时间等参数的计算,在保证读者服务至上的原则下,将排队论模型应用于引进了FRID技术的现代化图书馆,可节约资金,使设备的利用率最大化,更科学、合理地对引进了FRID技术的现代化图书馆进行资源配置优化。

  9. Einstein Critical-Slowing-Down is Siegel CyberWar Denial-of-Access Queuing/Pinning/ Jamming/Aikido Via Siegel DIGIT-Physics BEC ``Intersection''-BECOME-UNION Barabasi Network/GRAPH-Physics BEC: Strutt/Rayleigh-Siegel Percolation GLOBALITY-to-LOCALITY Phase-Transition Critical-Phenomenon (United States)

    Buick, Otto; Falcon, Pat; Alexander, G.; Siegel, Edward Carl-Ludwig


    Einstein[Dover(03)] critical-slowing-down(CSD)[Pais, Subtle in The Lord; Life & Sci. of Albert Einstein(81)] is Siegel CyberWar denial-of-access(DOA) operations-research queuing theory/pinning/jamming/.../Read [Aikido, Aikibojitsu & Natural-Law(90)]/Aikido(!!!) phase-transition critical-phenomenon via Siegel DIGIT-Physics (Newcomb[Am.J.Math. 4,39(1881)]-{Planck[(1901)]-Einstein[(1905)])-Poincare[Calcul Probabilités(12)-p.313]-Weyl [Goett.Nachr.(14); Math.Ann.77,313 (16)]-{Bose[(24)-Einstein[(25)]-Fermi[(27)]-Dirac[(1927)]}-``Benford''[Proc.Am.Phil.Soc. 78,4,551 (38)]-Kac[Maths.Stat.-Reasoning(55)]-Raimi[Sci.Am. 221,109 (69)...]-Jech[preprint, PSU(95)]-Hill[Proc.AMS 123,3,887(95)]-Browne[NYT(8/98)]-Antonoff-Smith-Siegel[AMS Joint-Mtg.,S.-D.(02)] algebraic-inversion to yield ONLY BOSE-EINSTEIN QUANTUM-statistics (BEQS) with ZERO-digit Bose-Einstein CONDENSATION(BEC) ``INTERSECTION''-BECOME-UNION to Barabasi[PRL 876,5632(01); Rev.Mod.Phys.74,47(02)...] Network /Net/GRAPH(!!!)-physics BEC: Strutt/Rayleigh(1881)-Polya(21)-``Anderson''(58)-Siegel[J.Non-crystalline-Sol.40,453(80)

  10. Sick of queuing? The Registration Service has the answer

    CERN Multimedia

    Antonella Del Rosso


    At the beginning of the year, CERN's Registration Service, in its fully renovated premises, launched a new initiative to save you time and to optimise the work of its staff.   One free-to-download application, two ticket printers and three screens: behind this simple-looking system sits an ingenious process (see the slideshow) that will enable you to avoid long waiting times at CERN's Registration Service. The Service delivers some 22 000 badges each year, reaching a peak of 700 per week, and is therefore one of the few places at CERN where queuing is the norm.  But that could all change thanks to Qminder, an app that allows users to monitor the waiting times in Building 55 from their smartphones. From today, you can take a virtual ticket using your device and see how long you will have to wait before your case is handled by the next available member of staff.  “The system can also provide statistics on waiting times in the various registration service...

  11. Spectrally queued feature selection for robotic visual odometery (United States)

    Pirozzo, David M.; Frederick, Philip A.; Hunt, Shawn; Theisen, Bernard; Del Rose, Mike


    Over the last two decades, research in Unmanned Vehicles (UV) has rapidly progressed and become more influenced by the field of biological sciences. Researchers have been investigating mechanical aspects of varying species to improve UV air and ground intrinsic mobility, they have been exploring the computational aspects of the brain for the development of pattern recognition and decision algorithms and they have been exploring perception capabilities of numerous animals and insects. This paper describes a 3 month exploratory applied research effort performed at the US ARMY Research, Development and Engineering Command's (RDECOM) Tank Automotive Research, Development and Engineering Center (TARDEC) in the area of biologically inspired spectrally augmented feature selection for robotic visual odometry. The motivation for this applied research was to develop a feasibility analysis on multi-spectrally queued feature selection, with improved temporal stability, for the purposes of visual odometry. The intended application is future semi-autonomous Unmanned Ground Vehicle (UGV) control as the richness of data sets required to enable human like behavior in these systems has yet to be defined.

  12. Queuing transitions in the asymmetric simple exclusion process (United States)

    Ha, Meesoon; Timonen, Jussi; den Nijs, Marcel


    Stochastic driven flow along a channel can be modeled by the asymmetric simple exclusion process. We confirm numerically the presence of a dynamic queuing phase transition at a nonzero obstruction strength, and establish its scaling properties. Below the transition, the traffic jam is macroscopic in the sense that the length of the queue scales linearly with system size. Above the transition, only a power-law shaped queue remains. Its density profile scales as δρ˜x-ν with ν=1/3, and x is the distance from the obstacle. We construct a heuristic argument, indicating that the exponent ν=1/3 is universal and independent of the dynamic exponent of the underlying dynamic process. Fast bonds create only power-law shaped depletion queues, and with an exponent that could be equal to ν=2/3, but the numerical results yield consistently somewhat smaller values ν≃0.63(3). The implications of these results to faceting of growing interfaces and localization of directed polymers in random media, both in the presence of a columnar defect are pointed out as well.

  13. Network performance analysis

    CERN Document Server

    Bonald, Thomas


    The book presents some key mathematical tools for the performance analysis of communication networks and computer systems.Communication networks and computer systems have become extremely complex. The statistical resource sharing induced by the random behavior of users and the underlying protocols and algorithms may affect Quality of Service.This book introduces the main results of queuing theory that are useful for analyzing the performance of these systems. These mathematical tools are key to the development of robust dimensioning rules and engineering methods. A number of examples i

  14. Queued Pareto Local Search for Multi-Objective Optimization

    NARCIS (Netherlands)

    Inja, M.; Kooijman, C.; de Waard, M.; Roijers, D.M.; Whiteson, S.


    Many real-world optimization problems involve balancing multiple objectives. When there is no solution that is best with respect to all objectives, it is often desirable to compute the Pareto front. This paper proposes queued Pareto local search (QPLS), which improves on existing Pareto local search

  15. Queuing Models: A Tool For Assessing The Profitability Of Barbing ...

    African Journals Online (AJOL)

    The study considered small scale business as an option in reducing the unemployment rate in our society. The study uses queuing models to assess the profitability of barbing salon business in Agbor town of Delta State. The result of the study indicates that the distribution of inter-arrival times, service times, and waiting ...

  16. Network operating system (United States)

    Perotto, E.


    The Network Operating System is an addition to CMS designed to allow multitasking operation, while conserving all the facilities of CMS: file system, interactivity, high level language environment. Multitasking is useful for server virtual machines, e.g. Network Transport Managers, File Managers, Disk space Managers, Tape Unit Managers, where the execution of a task involves long waits due to I/O completion, VCMF communication delays or human responses, during which the task status stays as a control block in memory, while the virtual machine serves other users executing the same lines of code. Multitasking is not only for multi-user service: a big data reduction program may run as a main task, while a side task, connected to the virtual console, gives reports on the ongoing work of the main task in response to user commands and steers the main task through common data. All the service routines (Wait, Create and Delete Task, Get and Release Buffer, VMCF Open and Close Link, Send and Receive, I/O and Console Routines) are FORTRAN callable, and may be used from any language environment consistent with the same parameter passing conventions. The outstanding feature of this system is efficiency, no user defined SVC are used, and the use of other privileged instructions as LPSW or SSM is the bare necessary, so that CP (with the associated overhead) is not too involved. System code and read-only data are write-protected with a different storage key from CMS and user program.

  17. Computer Networks A Systems Approach

    CERN Document Server

    Peterson, Larry L


    This best-selling and classic book teaches you the key principles of computer networks with examples drawn from the real world of network and protocol design. Using the Internet as the primary example, the authors explain various protocols and networking technologies. Their systems-oriented approach encourages you to think about how individual network components fit into a larger, complex system of interactions. Whatever your perspective, whether it be that of an application developer, network administrator, or a designer of network equipment or protocols, you will come away with a "big pictur

  18. Capacitated two-echelon inventory models for repairable item systems

    NARCIS (Netherlands)

    Avsar, Z.M.; Zijm, Willem H.M.; Gershwin, S.B.; Dallery, Y.; Papadopoulos, C.; Smith, J.M.


    In this paper, we consider two-echelon maintenance systems with repair facilities both at a number of local service centers (called bases) and at a central location. Each repair facility may be considered to be a job shop and is modeled as a (limited capacity) open queuing network, while any

  19. Efficient round-robin multicast scheduling for input-queued switches

    DEFF Research Database (Denmark)

    Rasmussen, Anders; Yu, Hao; Ruepp, Sarah Renée


    problem. Using a separate queue for each output port at an input to reduce the HOL blocking, that is, the virtual output queuing discipline, increases the implementation complexity, which limits the scalability. Given the increasing link speed and network capacity, a low-complexity yet efficient multicast...... scheduling algorithm is required for next generation high-speed networks. This study proposes the novel efficient round-robin multicast scheduling algorithm for IQ architectures and demonstrates how this algorithm can be implemented as a hardware solution, which alleviates the multicast HOL blocking issue...... synthesis results show that the proposed algorithm can be very efficiently implemented in hardware to perform multicast scheduling at very high speeds with only modest resource requirements....

  20. Network of networks in Linux operating system (United States)

    Wang, Haoqin; Chen, Zhen; Xiao, Guanping; Zheng, Zheng


    Operating system represents one of the most complex man-made systems. In this paper, we analyze Linux Operating System (LOS) as a complex network via modeling functions as nodes and function calls as edges. It is found that for the LOS network and modularized components within it, the out-degree follows an exponential distribution and the in-degree follows a power-law distribution. For better understanding the underlying design principles of LOS, we explore the coupling correlations of components in LOS from aspects of topology and function. The result shows that the component for device drivers has a strong manifestation in topology while a weak manifestation in function. However, the component for process management shows the contrary phenomenon. Moreover, in an effort to investigate the impact of system failures on networks, we make a comparison between the networks traced from normal and failure status of LOS. This leads to a conclusion that the failure will change function calls which should be executed in normal status and introduce new function calls in the meanwhile.

  1. Views of wireless network systems.

    Energy Technology Data Exchange (ETDEWEB)

    Young, William Frederick; Duggan, David Patrick


    Wireless networking is becoming a common element of industrial, corporate, and home networks. Commercial wireless network systems have become reliable, while the cost of these solutions has become more affordable than equivalent wired network solutions. The security risks of wireless systems are higher than wired and have not been studied in depth. This report starts to bring together information on wireless architectures and their connection to wired networks. We detail information contained on the many different views of a wireless network system. The method of using multiple views of a system to assist in the determination of vulnerabilities comes from the Information Design Assurance Red Team (IDART{trademark}) Methodology of system analysis developed at Sandia National Laboratories.

  2. Mapping biological systems to network systems

    CERN Document Server

    Rathore, Heena


    The book presents the challenges inherent in the paradigm shift of network systems from static to highly dynamic distributed systems – it proposes solutions that the symbiotic nature of biological systems can provide into altering networking systems to adapt to these changes. The author discuss how biological systems – which have the inherent capabilities of evolving, self-organizing, self-repairing and flourishing with time – are inspiring researchers to take opportunities from the biology domain and map them with the problems faced in network domain. The book revolves around the central idea of bio-inspired systems -- it begins by exploring why biology and computer network research are such a natural match. This is followed by presenting a broad overview of biologically inspired research in network systems -- it is classified by the biological field that inspired each topic and by the area of networking in which that topic lies. Each case elucidates how biological concepts have been most successfully ...

  3. Risks in Networked Computer Systems


    Klingsheim, André N.


    Networked computer systems yield great value to businesses and governments, but also create risks. The eight papers in this thesis highlight vulnerabilities in computer systems that lead to security and privacy risks. A broad range of systems is discussed in this thesis: Norwegian online banking systems, the Norwegian Automated Teller Machine (ATM) system during the 90's, mobile phones, web applications, and wireless networks. One paper also comments on legal risks to bank cust...

  4. [Network structures in biological systems]. (United States)

    Oleskin, A V


    Network structures (networks) that have been extensively studied in the humanities are characterized by cohesion, a lack of a central control unit, and predominantly fractal properties. They are contrasted with structures that contain a single centre (hierarchies) as well as with those whose elements predominantly compete with one another (market-type structures). As far as biological systems are concerned, their network structures can be subdivided into a number of types involving different organizational mechanisms. Network organization is characteristic of various structural levels of biological systems ranging from single cells to integrated societies. These networks can be classified into two main subgroups: (i) flat (leaderless) network structures typical of systems that are composed of uniform elements and represent modular organisms or at least possess manifest integral properties and (ii) three-dimensional, partly hierarchical structures characterized by significant individual and/or intergroup (intercaste) differences between their elements. All network structures include an element that performs structural, protective, and communication-promoting functions. By analogy to cell structures, this element is denoted as the matrix of a network structure. The matrix includes a material and an immaterial component. The material component comprises various structures that belong to the whole structure and not to any of its elements per se. The immaterial (ideal) component of the matrix includes social norms and rules regulating network elements' behavior. These behavioral rules can be described in terms of algorithms. Algorithmization enables modeling the behavior of various network structures, particularly of neuron networks and their artificial analogs.

  5. Language Networks as Complex Systems (United States)

    Lee, Max Kueiming; Ou, Sheue-Jen


    Starting in the late eighties, with a growing discontent with analytical methods in science and the growing power of computers, researchers began to study complex systems such as living organisms, evolution of genes, biological systems, brain neural networks, epidemics, ecology, economy, social networks, etc. In the early nineties, the research…

  6. Financial Network Systemic Risk Contributions

    NARCIS (Netherlands)

    Hautsch, N.; Schaumburg, J.; Schienle, M.


    We propose the realized systemic risk beta as a measure of financial companies' contribution to systemic risk, given network interdependence between firms' tail risk exposures. Conditional on statistically pre-identified network spillover effects and market and balance sheet information, we define

  7. Priority Queuing Models for Hospital Intensive Care Units and Impacts to Severe Case Patients (United States)

    Hagen, Matthew S.; Jopling, Jeffrey K; Buchman, Timothy G; Lee, Eva K.


    This paper examines several different queuing models for intensive care units (ICU) and the effects on wait times, utilization, return rates, mortalities, and number of patients served. Five separate intensive care units at an urban hospital are analyzed and distributions are fitted for arrivals and service durations. A system-based simulation model is built to capture all possible cases of patient flow after ICU admission. These include mortalities and returns before and after hospital exits. Patients are grouped into 9 different classes that are categorized by severity and length of stay (LOS). Each queuing model varies by the policies that are permitted and by the order the patients are admitted. The first set of models does not prioritize patients, but examines the advantages of smoothing the operating schedule for elective surgeries. The second set analyzes the differences between prioritizing admissions by expected LOS or patient severity. The last set permits early ICU discharges and conservative and aggressive bumping policies are contrasted. It was found that prioritizing patients by severity considerably reduced delays for critical cases, but also increased the average waiting time for all patients. Aggressive bumping significantly raised the return and mortality rates, but more conservative methods balance quality and efficiency with lowered wait times without serious consequences. PMID:24551379

  8. Networking systems design and development

    CERN Document Server

    Chao, Lee


    Effectively integrating theory and hands-on practice, Networking Systems Design and Development provides students and IT professionals with the knowledge and skills needed to design, implement, and manage fully functioning network systems using readily available Linux networking tools. Recognizing that most students are beginners in the field of networking, the text provides step-by-step instruction for setting up a virtual lab environment at home. Grounded in real-world applications, this book provides the ideal blend of conceptual instruction and lab work to give students and IT professional

  9. Communicating embedded systems networks applications

    CERN Document Server

    Krief, Francine


    Embedded systems become more and more complex and require having some knowledge in various disciplines such as electronics, data processing, telecommunications and networks. Without detailing all the aspects related to the design of embedded systems, this book, which was written by specialists in electronics, data processing and telecommunications and networks, gives an interesting point of view of communication techniques and problems in embedded systems. This choice is easily justified by the fact that embedded systems are today massively communicating and that telecommunications and network


    Directory of Open Access Journals (Sweden)

    V. V. Naumenko


    Full Text Available Markov queuing network with income in transient regime is considered. It has positive and negative messages, which can be used in forecasting income of information and telecommunication systems and networks affected by viruses. Investigations are carried out in the cases when incomes from transitions between network states are deterministic functions dependent on states, or they are random variables with given mean values. In the last case it is assumed that all network systems operate in a high load mode. An example is given.

  11. Delays and networked control systems

    CERN Document Server

    Hetel, Laurentiu; Daafouz, Jamal; Johansson, Karl


    This edited monograph includes state-of-the-art contributions on continuous time dynamical networks with delays. The book is divided into four parts. The first part presents tools and methods for the analysis of time-delay systems with a particular attention on control problems of large scale or infinite-dimensional systems with delays. The second part of the book is dedicated to the use of time-delay models for the analysis and design of Networked Control Systems. The third part of the book focuses on the analysis and design of systems with asynchronous sampling intervals which occur in Networked Control Systems. The last part of the book exposes several contributions dealing with the design of cooperative control and observation laws for networked control systems. The target audience primarily comprises researchers and experts in the field of control theory, but the book may also be beneficial for graduate students. .

  12. Resource Management in Computing Systems


    Amani, Payam


    Resource management is an essential building block of any modern computer and communication network. In this thesis, the results of our research in the following two tracks are summarized in four papers. The first track includes three papers and covers modeling, prediction and control for multi-tier computing systems. In the first paper, a NARX-based multi-step-ahead response time predictor for single server queuing systems is presented which can be applied to CPU-constrained computing system...

  13. Interorganizational Innovation in Systemic Networks

    DEFF Research Database (Denmark)

    Seemann, Janne; Dinesen, Birthe; Gustafsson, Jeppe


    that linear n-stage models by reducing complexity and flux end up focusing only on the surface of the network and are thus unable to grasp important aspects of network dynamics. The paper suggests that there is a need for a more dynamic innovation model able to grasp the whole picture of dynamics in systemic...... patients with chronic obstructive pulmonary disease (COPD) to avoid readmission, perform self monitoring and to maintain rehabilitation in their homes. The aim of the paper is to identify, analyze and discuss innovation dynamics in the COPD network and on a preliminary basis to identify implications...... for managing innovations in systemic networks. The main argument of this paper is that innovation dynamics in systemic networks should be understood as a complex interplay of four logics: 1) Fragmented innovation, 2) Interface innovation, 3) Competing innovation, 4) Co-innovation. The findings indicate...

  14. Asynchronous control for networked systems

    CERN Document Server

    Rubio, Francisco; Bencomo, Sebastián


    This book sheds light on networked control systems; it describes different techniques for asynchronous control, moving away from the periodic actions of classical control, replacing them with state-based decisions and reducing the frequency with which communication between subsystems is required. The text focuses specially on event-based control. Split into two parts, Asynchronous Control for Networked Systems begins by addressing the problems of single-loop networked control systems, laying out various solutions which include two alternative model-based control schemes (anticipatory and predictive) and the use of H2/H∞ robust control to deal with network delays and packet losses. Results on self-triggering and send-on-delta sampling are presented to reduce the need for feedback in the loop. In Part II, the authors present solutions for distributed estimation and control. They deal first with reliable networks and then extend their results to scenarios in which delays and packet losses may occur. The novel ...

  15. Performance of Networked Control Systems

    Directory of Open Access Journals (Sweden)

    Yingwei Zhang


    Full Text Available Data packet dropout is a special kind of time delay problem. In this paper, predictive controllers for networked control systems (NCSs with dual-network are designed by model predictive control method. The contributions are as follows. (1 The predictive control problem of the dual-network is considered. (2 The predictive performance of the dual-network is evaluated. (3 Compared to the popular networked control systems, the optimal controller of the new NCSs with data packets dropout is designed, which can minimize infinite performance index at each sampling time and guarantee the closed-loop system stability. Finally, the simulation results show the feasibility and effectiveness of the controllers designed.

  16. A message-queuing framework for STAR's online monitoring and metadata collection

    Energy Technology Data Exchange (ETDEWEB)

    Arkhipkin, D.; Lauret, J.; Betts, W.


    We report our experience on migrating STARs Online Services (Run Control System, Data Acquisition System, Slow Control System and Subsystem Monitoring) from direct read/write database accesses to a modern non-blocking message-oriented infrastructure. Based on the Advanced Messaging Queuing Protocol (AMQP) and standards, this novel approach does not specify the message data structure, allowing great flexibility in its use. After careful consideration, we chose Google Protocol Buffers as our primary (de)serialization format for structured data exchange. This migration allows us to reduce the overall system complexity and greatly improve the reliability of the metadata collection and the performance of our online services in general. We will present this new framework through its software architecture overview, providing details about our staged and non-disruptive migration process as well as details of the implementation of pluggable components to provide future improvements without compromising stability and availability of services.

  17. Teleradiology system analysis using a discrete event-driven block-oriented network simulator (United States)

    Stewart, Brent K.; Dwyer, Samuel J., III


    Performance evaluation and trade-off analysis are the central issues in the design of communication networks. Simulation plays an important role in computer-aided design and analysis of communication networks and related systems, allowing testing of numerous architectural configurations and fault scenarios. We are using the Block Oriented Network Simulator (BONeS, Comdisco, Foster City, CA) software package to perform discrete, event- driven Monte Carlo simulations in capacity planning, tradeoff analysis and evaluation of alternate architectures for a high-speed, high-resolution teleradiology project. A queuing network model of the teleradiology system has been devise, simulations executed and results analyzed. The wide area network link uses a switched, dial-up N X 56 kbps inverting multiplexer where the number of digital voice-grade lines (N) can vary from one (DS-0) through 24 (DS-1). The proposed goal of such a system is 200 films (2048 X 2048 X 12-bit) transferred between a remote and local site in an eight hour period with a mean delay time less than five minutes. It is found that: (1) the DS-1 service limit is around 100 films per eight hour period with a mean delay time of 412 +/- 39 seconds, short of the goal stipulated above; (2) compressed video teleconferencing can be run simultaneously with image data transfer over the DS-1 wide area network link without impacting the performance of the described teleradiology system; (3) there is little sense in upgrading to a higher bandwidth WAN link like DS-2 or DS-3 for the current system; and (4) the goal of transmitting 200 films in an eight hour period with a mean delay time less than five minutes can be achieved simply if the laser printer interface is updated from the current DR-11W interface to a much faster SCSI interface.

  18. A Survey of Wireless Fair Queuing Algorithms with Location-Dependent Channel Errors

    Directory of Open Access Journals (Sweden)

    Anca VARGATU


    Full Text Available The rapid development of wireless networks has brought more and more attention to topics related to fair allocation of resources, creation of suitable algorithms, taking into account the special characteristics of wireless environment and insurance fair access to the transmission channel, with delay bound and throughput guaranteed. Fair allocation of resources in wireless networks requires significant challenges, because of errors that occur only in these networks, such as location-dependent and bursty channel errors. In wireless networks, frequently happens, because interference of radio waves, that a user experiencing bad radio conditions during a period of time, not to receive resources in that period. This paper analyzes some resource allocation algorithms for wireless networks with location dependent errors, specifying the base idea for each algorithm and the way how it works. The analyzed fair queuing algorithms differ by the way they treat the following aspects: how to select the flows which should receive additional services, how to allocate these resources, which is the proportion received by error free flows and how the flows affected by errors are compensated.

  19. Reducing external speedup requirements for input-queued crossbars

    DEFF Research Database (Denmark)

    Berger, Michael Stubert


    This paper presents a modified architecture for an input queued switch that reduces external speedup. Maximal size scheduling algorithms for input-buffered crossbars requires a speedup between port card and switch card. The speedup is typically in the range of 2, to compensate for the scheduler...... performance degradation. This implies, that the required bandwidth between port card and switch card is 2 times the actual port speed, adding to cost and complexity. To reduce this bandwidth, a modified architecture is proposed that introduces a small amount of input and output memory on the switch card chip...


    Directory of Open Access Journals (Sweden)

    Cleomar Valois Batista Jr


    Full Text Available The continued and diversified growth of social networks has changed the way in which users interact with them. With these changes, what once was limited to social contact is now used for exchanging ideas and opinions, creating the need for new features. Users have so much information at their fingertips that they are unable to process it by themselves; hence, the need to develop new tools. Recommender systems were developed to address this need and many techniques were used for different approaches to the problem. To make relevant recommendations, these systems use large sets of data, not taking the social network of the user into consideration. Developing a recommender system that takes into account the social network of the user is another way of tackling the problem. The purpose of this project is to use the theory of six degrees of separation (Watts 2003 amongst users of a social network to enhance existing recommender systems.

  1. Behavioural queuing: an agent based modelling approach


    Sankaranarayanan Karthik; Arturo Delgado-Alvarez Carlos; R Larsen Erik; van Ackere Ann


    Queueing research has a plethora of applications and has been an area of study spanning from telecommunications to economics. Traditionally studies on queueing has mainly concentrated on design performance and running of the service facility with customers arriving following a stochastic process. In this paper we take an agent based modeling approach to develop a behavioral model of a queueing system using Cellular Automata (CA). We study how adaptive expectation along with a simple informati...

  2. Multilevel Complex Networks and Systems (United States)

    Caldarelli, Guido


    Network theory has been a powerful tool to model isolated complex systems. However, the classical approach does not take into account the interactions often present among different systems. Hence, the scientific community is nowadays concentrating the efforts on the foundations of new mathematical tools for understanding what happens when multiple networks interact. The case of economic and financial networks represents a paramount example of multilevel networks. In the case of trade, trade among countries the different levels can be described by the different granularity of the trading relations. Indeed, we have now data from the scale of consumers to that of the country level. In the case of financial institutions, we have a variety of levels at the same scale. For example one bank can appear in the interbank networks, ownership network and cds networks in which the same institution can take place. In both cases the systemically important vertices need to be determined by different procedures of centrality definition and community detection. In this talk I will present some specific cases of study related to these topics and present the regularities found. Acknowledged support from EU FET Project ``Multiplex'' 317532.

  3. Promoting Social Network Awareness: A Social Network Monitoring System (United States)

    Cadima, Rita; Ferreira, Carlos; Monguet, Josep; Ojeda, Jordi; Fernandez, Joaquin


    To increase communication and collaboration opportunities, members of a community must be aware of the social networks that exist within that community. This paper describes a social network monitoring system--the KIWI system--that enables users to register their interactions and visualize their social networks. The system was implemented in a…

  4. Plant systems biology: network matters. (United States)

    Lucas, Mikaël; Laplaze, Laurent; Bennett, Malcolm J


    Systems biology is all about networks. A recent trend has been to associate systems biology exclusively with the study of gene regulatory or protein-interaction networks. However, systems biology approaches can be applied at many other scales, from the subatomic to the ecosystem scales. In this review, we describe studies at the sub-cellular, tissue, whole plant and crop scales and highlight how these studies can be related to systems biology. We discuss the properties of system approaches at each scale as well as their current limits, and pinpoint in each case advances unique to the considered scale but representing potential for the other scales. We conclude by examining plant models bridging different scales and considering the future prospects of plant systems biology. © 2011 Blackwell Publishing Ltd.

  5. Networks, linkages, and migration systems. (United States)

    Fawcett, J T


    Recent theoretical interest in migration systems calls attention to the functions of diverse linkages between countries in stimulating, directing,and maintaining international flows of people. This article proposes a conceptual framework for the non-people linkages in international migration systems and discusses the implications for population movement of the 4 categories and 3 types of linkages that define the network. The 4 categories include 1) state to state relations, 2) mass culture connections, 3) family and personal networks, and 4) migrant agency activities. The 3 types of linkages are 1) tangible linkages, 2) regulatory linkages, and 3) relational linkages.

  6. Network operating system focus technology (United States)


    An activity structured to provide specific design requirements and specifications for the Space Station Data Management System (DMS) Network Operating System (NOS) is outlined. Examples are given of the types of supporting studies and implementation tasks presently underway to realize a DMS test bed capability to develop hands-on understanding of NOS requirements as driven by actual subsystem test beds participating in the overall Johnson Space Center test bed program. Classical operating system elements and principal NOS functions are listed.

  7. Networked control of microgrid system of systems (United States)

    Mahmoud, Magdi S.; Rahman, Mohamed Saif Ur; AL-Sunni, Fouad M.


    The microgrid has made its mark in distributed generation and has attracted widespread research. However, microgrid is a complex system which needs to be viewed from an intelligent system of systems perspective. In this paper, a network control system of systems is designed for the islanded microgrid system consisting of three distributed generation units as three subsystems supplying a load. The controller stabilises the microgrid system in the presence of communication infractions such as packet dropouts and delays. Simulation results are included to elucidate the effectiveness of the proposed control strategy.

  8. TCP congestion control in input-queued crossbar switch (United States)

    Zheng, Hongyun; Zhao, Yongxiang; Chen, Changjia


    In this paper, we consider congestion control in input queued crossbar switch environment where each input port with finite buffer space while TCP protocol is employed for end-to-end congestion control. We find that it is impossible to achieve efficiency and fairness among TCP flows at the same time only by queue management. Then we propose a scheme of hFS&rEDF, which combine heuristic fair switch arbitration (hFS) and queue management policy of early drop front randomly (rEDF). In our proposed scheme, switch arbitration strategy of hFS unevenly allows input ports to transfer packets to output ports while packets at head of any other input ports involved in conflicts have to be dropped by the policy of rEDF with a probability. Simulation results prove that our proposed scheme can achieve better tradeoff between throughput and fairness.

  9. Architecting Communication Network of Networks for Space System of Systems (United States)

    Bhasin, Kul B.; Hayden, Jeffrey L.


    The National Aeronautics and Space Administration (NASA) and the Department of Defense (DoD) are planning Space System of Systems (SoS) to address the new challenges of space exploration, defense, communications, navigation, Earth observation, and science. In addition, these complex systems must provide interoperability, enhanced reliability, common interfaces, dynamic operations, and autonomy in system management. Both NASA and the DoD have chosen to meet the new demands with high data rate communication systems and space Internet technologies that bring Internet Protocols (IP), routers, servers, software, and interfaces to space networks to enable as much autonomous operation of those networks as possible. These technologies reduce the cost of operations and, with higher bandwidths, support the expected voice, video, and data needed to coordinate activities at each stage of an exploration mission. In this paper, we discuss, in a generic fashion, how the architectural approaches and processes are being developed and used for defining a hypothetical communication and navigation networks infrastructure to support lunar exploration. Examples are given of the products generated by the architecture development process.

  10. Network centrality of metro systems.

    Directory of Open Access Journals (Sweden)

    Sybil Derrible

    Full Text Available Whilst being hailed as the remedy to the world's ills, cities will need to adapt in the 21(st century. In particular, the role of public transport is likely to increase significantly, and new methods and technics to better plan transit systems are in dire need. This paper examines one fundamental aspect of transit: network centrality. By applying the notion of betweenness centrality to 28 worldwide metro systems, the main goal of this paper is to study the emergence of global trends in the evolution of centrality with network size and examine several individual systems in more detail. Betweenness was notably found to consistently become more evenly distributed with size (i.e. no "winner takes all" unlike other complex network properties. Two distinct regimes were also observed that are representative of their structure. Moreover, the share of betweenness was found to decrease in a power law with size (with exponent 1 for the average node, but the share of most central nodes decreases much slower than least central nodes (0.87 vs. 2.48. Finally the betweenness of individual stations in several systems were examined, which can be useful to locate stations where passengers can be redistributed to relieve pressure from overcrowded stations. Overall, this study offers significant insights that can help planners in their task to design the systems of tomorrow, and similar undertakings can easily be imagined to other urban infrastructure systems (e.g., electricity grid, water/wastewater system, etc. to develop more sustainable cities.

  11. Systems engineering technology for networks (United States)


    The report summarizes research pursued within the Systems Engineering Design Laboratory at Virginia Polytechnic Institute and State University between May 16, 1993 and January 31, 1994. The project was proposed in cooperation with the Computational Science and Engineering Research Center at Howard University. Its purpose was to investigate emerging systems engineering tools and their applicability in analyzing the NASA Network Control Center (NCC) on the basis of metrics and measures.

  12. Maximizing Weapon System Availability With a Multi-Echelon Supply Network (United States)


    that system availability is maximized. This thesis develops a stochastic optimization model that prescribes optimal investments in spare parts for... stochastic optimization to maximize the expected number of time periods a weapon system is 2 available for use. The key decisions in our model ...stationary demands over time. Simchi-Levi and Zhao provide methods for evaluating stochastic , multi-echelon inventory systems , specifically, the queuing

  13. The LILARTI neural network system

    Energy Technology Data Exchange (ETDEWEB)

    Allen, J.D. Jr.; Schell, F.M.; Dodd, C.V.


    The material of this Technical Memorandum is intended to provide the reader with conceptual and technical background information on the LILARTI neural network system of detail sufficient to confer an understanding of the LILARTI method as it is presently allied and to facilitate application of the method to problems beyond the scope of this document. Of particular importance in this regard are the descriptive sections and the Appendices which include operating instructions, partial listings of program output and data files, and network construction information.

  14. Facsimile Network System in RCP (United States)

    Muramatsu, Kazuya

    Recruit Computer Print Corp. has compiled Weekly Housing Magazine by use of its own CTS (Computerized Type Setting) resulting in the real estate database as byproduct. Based on the database it has made the network linking with sponsors, real estate companies. It has transmitted lists for data cleaning directly from computer enabling to save manpower and reduce time in the compilation process. The author describes the objectives, details, functions and promise of the system.

  15. Modeling and evaluation of information systems using coloured petri network

    Directory of Open Access Journals (Sweden)

    Ehsan Zamirpour


    Full Text Available Nowadays with the growth of organizations and their affiliates, the importance of information systems has increased. Functional and non-functional requirements of information systems in an organization are supported. There are literally several techniques to support the functional requirements in terms of software methodologies, but support for the second set of requirements has received little attention. Software Performance Engineering (SPE forum tries to address this issue by presenting software methodologies to support both types of requirements. In this paper, we present a formal model for the evaluation of system performance based on a pragmatic model. Because of supporting the concurrency concepts, petri net has a higher priority than queuing system. For mapping UML to colored Petri net diagram, we use an intermediate graph. The preliminary results indicate that the proposed model may save significant amount of computations.

  16. Network Centrality of Metro Systems (United States)

    Derrible, Sybil


    Whilst being hailed as the remedy to the world’s ills, cities will need to adapt in the 21st century. In particular, the role of public transport is likely to increase significantly, and new methods and technics to better plan transit systems are in dire need. This paper examines one fundamental aspect of transit: network centrality. By applying the notion of betweenness centrality to 28 worldwide metro systems, the main goal of this paper is to study the emergence of global trends in the evolution of centrality with network size and examine several individual systems in more detail. Betweenness was notably found to consistently become more evenly distributed with size (i.e. no “winner takes all”) unlike other complex network properties. Two distinct regimes were also observed that are representative of their structure. Moreover, the share of betweenness was found to decrease in a power law with size (with exponent 1 for the average node), but the share of most central nodes decreases much slower than least central nodes (0.87 vs. 2.48). Finally the betweenness of individual stations in several systems were examined, which can be useful to locate stations where passengers can be redistributed to relieve pressure from overcrowded stations. Overall, this study offers significant insights that can help planners in their task to design the systems of tomorrow, and similar undertakings can easily be imagined to other urban infrastructure systems (e.g., electricity grid, water/wastewater system, etc.) to develop more sustainable cities. PMID:22792373

  17. Using queuing theory to analyse the government's 4-H completion time target in accident and emergency departments. (United States)

    Mayhew, L; Smith, D


    This paper uses a queuing model to evaluate completion times in Accident and Emergency (A&E) departments in the light of the Government target of completing and discharging 98% of patients inside 4 h. It illustrates how flows though an A&E can be accurately represented as a queuing process, how outputs can be used to visualise and interpret the 4-h Government target in a simple way and how the model can be used to assess the practical achievability of A&E targets in the future. The paper finds that A&E targets have resulted in significant improvements in completion times and thus deal with a major source of complaint by users of the National Health Service in the U.K. It suggests that whilst some of this improvement is attributable to better management, some is also due to the way some patients in A&E are designated and therefore counted through the system. It finds for example that the current target would not have been possible without some form of patient re-designation or re-labelling taking place. Further it finds that the current target is so demanding that the integrity of reported performance is open to question. Related incentives and demand management issues resulting from the target are also briefly discussed.

  18. Endogenous network of firms and systemic risk (United States)

    Ma, Qianting; He, Jianmin; Li, Shouwei


    We construct an endogenous network characterized by commercial credit relationships connecting the upstream and downstream firms. Simulation results indicate that the endogenous network model displays a scale-free property which exists in real-world firm systems. In terms of the network structure, with the expansion of the scale of network nodes, the systemic risk increases significantly, while the heterogeneities of network nodes have no effect on systemic risk. As for firm micro-behaviors, including the selection range of trading partners, actual output, labor requirement, price of intermediate products and employee salaries, increase of all these parameters will lead to higher systemic risk.

  19. Large scale network-centric distributed systems

    CERN Document Server

    Sarbazi-Azad, Hamid


    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


    Directory of Open Access Journals (Sweden)

    Santosh Kumar Chaudhari


    Full Text Available A Network Management System (NMS plays a very important role in managing an ever-evolving telecommunication network. Generally an NMS monitors & maintains the health of network elements. The growing size of the network warrants extra functionalities from the NMS. An NMS provides all kinds of information about networks which can be used for other purposes apart from monitoring & maintaining networks like improving QoS & saving energy in the network. In this paper, we add another dimension to NMS services, namely, making an NMS energy aware. We propose a Decision Management System (DMS framework which uses a machine learning technique called Bayesian Belief Networks (BBN, to make the NMS energy aware. The DMS is capable of analysing and making control decisions based on network traffic. We factor in the cost of rerouting and power saving per port. Simulations are performed on standard network topologies, namely, ARPANet and IndiaNet. It is found that ~2.5-6.5% power can be saved.

  1. System and Network Security Acronyms and Abbreviations (United States)


    Systems Agency DLL dynamic link library DMA direct memory access DMZ demilitarized zone DN distinguished name DN domain name DNP Distributed...NetBIOS Network Basic Input/Output System NetBT NetBIOS over TCP/IP NFAT network forensic analysis tool NFC near field communication NFS network file...Software Reference Library NSS Network Security Services NSTB National SCADA Test Bed NSTISSC National Security Telecommunications and Information

  2. Creation and analysis of software for modeling Markovian queuing systems


    Lazauskas, Tomas


    Darbe bus nagrinėjama mišraus tipo masinė aptarnavimo sistema, kurią gali sudaryti n paraiškų šaltinių, su atitinkamais paprasčiausių srautų intensyvumais, o paraiškos gali būti paskirstomos į m aptarnavimo įrenginių su fiksuotomis prioritetinėmis paraiškų eilėmis, kur paraiškos aptarnavimo laikas S yra pasiskirstęs pagal apibendrintą tikimybinio skirstinio funkciją G(t). Darbo tikslas – sukurti programinę įrangą, kuri pagal pateiktą sistemos funkcionavimo aprašymą schematine struktūra aps...

  3. Experimental energy consumption of Frame Slotted ALOHA and Distributed Queuing for data collection scenarios. (United States)

    Tuset-Peiro, Pere; Vazquez-Gallego, Francisco; Alonso-Zarate, Jesus; Alonso, Luis; Vilajosana, Xavier


    Data collection is a key scenario for the Internet of Things because it enables gathering sensor data from distributed nodes that use low-power and long-range wireless technologies to communicate in a single-hop approach. In this kind of scenario, the network is composed of one coordinator that covers a particular area and a large number of nodes, typically hundreds or thousands, that transmit data to the coordinator upon request. Considering this scenario, in this paper we experimentally validate the energy consumption of two Medium Access Control (MAC) protocols, Frame Slotted ALOHA (FSA) and Distributed Queuing (DQ). We model both protocols as a state machine and conduct experiments to measure the average energy consumption in each state and the average number of times that a node has to be in each state in order to transmit a data packet to the coordinator. The results show that FSA is more energy efficient than DQ if the number of nodes is known a priori because the number of slots per frame can be adjusted accordingly. However, in such scenarios the number of nodes cannot be easily anticipated, leading to additional packet collisions and a higher energy consumption due to retransmissions. Contrarily, DQ does not require to know the number of nodes in advance because it is able to efficiently construct an ad hoc network schedule for each collection round. This kind of a schedule ensures that there are no packet collisions during data transmission, thus leading to an energy consumption reduction above 10% compared to FSA.

  4. Experimental Energy Consumption of Frame Slotted ALOHA and Distributed Queuing for Data Collection Scenarios

    Directory of Open Access Journals (Sweden)

    Pere Tuset-Peiro


    Full Text Available Data collection is a key scenario for the Internet of Things because it enables gathering sensor data from distributed nodes that use low-power and long-range wireless technologies to communicate in a single-hop approach. In this kind of scenario, the network is composed of one coordinator that covers a particular area and a large number of nodes, typically hundreds or thousands, that transmit data to the coordinator upon request. Considering this scenario, in this paper we experimentally validate the energy consumption of two Medium Access Control (MAC protocols, Frame Slotted ALOHA (FSA and Distributed Queuing (DQ. We model both protocols as a state machine and conduct experiments to measure the average energy consumption in each state and the average number of times that a node has to be in each state in order to transmit a data packet to the coordinator. The results show that FSA is more energy efficient than DQ if the number of nodes is known a priori because the number of slots per frame can be adjusted accordingly. However, in such scenarios the number of nodes cannot be easily anticipated, leading to additional packet collisions and a higher energy consumption due to retransmissions. Contrarily, DQ does not require to know the number of nodes in advance because it is able to efficiently construct an ad hoc network schedule for each collection round. This kind of a schedule ensures that there are no packet collisions during data transmission, thus leading to an energy consumption reduction above 10% compared to FSA.

  5. Filtering and control of wireless networked systems

    CERN Document Server

    Zhang, Dan; Yu, Li


    This self-contained book, written by leading experts, offers a cutting-edge, in-depth overview of the filtering and control of wireless networked systems. It addresses the energy constraint and filter/controller gain variation problems, and presents both the centralized and the distributed solutions. The first two chapters provide an introduction to networked control systems and basic information on system analysis. Chapters (3–6) then discuss the centralized filtering of wireless networked systems, presenting different approaches to deal with energy efficiency and filter/controller gain variation problems. The next part (chapters 7–10) explores the distributed filtering of wireless networked systems, addressing the main problems of energy constraint and filter gain variation. The final part (chapters 11–14) focuses on the distributed control of wireless networked systems. networked systems for communication and control applications, the bo...

  6. Variability of Green Time to Discharge a Specified Number of Queued Vehicles at a Signalized Intersection

    Directory of Open Access Journals (Sweden)

    Yi Zhao


    Full Text Available The aim of this paper is to study the headway distribution of queued vehicles (less than 16 vehicles at signalized intersections. Existing studies usually take the average statistics of headway at any queuing place. When different percentile points of statistical data are assigned to headway, the passing rate (the rate of all queued vehicles passing the stop line under the ideal signal timing scheme varies. When selecting the mean value, the passing rate of a queue of fewer than 16 vehicles is no more than 65%. When selecting 75% as the percentile, the passing rate is up to 94%. The queue length also decides the assigned percentile of headway to ensure the passing rate reaches a certain level. The value assignation of headway directly affects lane capacity and start-up loss time. This paper provides a new perspective on parameter calibration and will make the signal timing algorithm method more effective.

  7. Operating systems and network protocols for wireless sensor networks. (United States)

    Dutta, Prabal; Dunkels, Adam


    Sensor network protocols exist to satisfy the communication needs of diverse applications, including data collection, event detection, target tracking and control. Network protocols to enable these services are constrained by the extreme resource scarcity of sensor nodes-including energy, computing, communications and storage-which must be carefully managed and multiplexed by the operating system. These challenges have led to new protocols and operating systems that are efficient in their energy consumption, careful in their computational needs and miserly in their memory footprints, all while discovering neighbours, forming networks, delivering data and correcting failures.

  8. Network Intrusion Detection System using Apache Storm

    Directory of Open Access Journals (Sweden)

    Muhammad Asif Manzoor


    Full Text Available Network security implements various strategies for the identification and prevention of security breaches. Network intrusion detection is a critical component of network management for security, quality of service and other purposes. These systems allow early detection of network intrusion and malicious activities; so that the Network Security infrastructure can react to mitigate these threats. Various systems are proposed to enhance the network security. We are proposing to use anomaly based network intrusion detection system in this work. Anomaly based intrusion detection system can identify the new network threats. We also propose to use Real-time Big Data Stream Processing Framework, Apache Storm, for the implementation of network intrusion detection system. Apache Storm can help to manage the network traffic which is generated at enormous speed and size and the network traffic speed and size is constantly increasing. We have used Support Vector Machine in this work. We use Knowledge Discovery and Data Mining 1999 (KDD’99 dataset to test and evaluate our proposed solution.

  9. Model-based control of networked systems

    CERN Document Server

    Garcia, Eloy; Montestruque, Luis A


    This monograph introduces a class of networked control systems (NCS) called model-based networked control systems (MB-NCS) and presents various architectures and control strategies designed to improve the performance of NCS. The overall performance of NCS considers the appropriate use of network resources, particularly network bandwidth, in conjunction with the desired response of the system being controlled.   The book begins with a detailed description of the basic MB-NCS architecture that provides stability conditions in terms of state feedback updates . It also covers typical problems in NCS such as network delays, network scheduling, and data quantization, as well as more general control problems such as output feedback control, nonlinear systems stabilization, and tracking control.   Key features and topics include: Time-triggered and event-triggered feedback updates Stabilization of uncertain systems subject to time delays, quantization, and extended absence of feedback Optimal control analysis and ...

  10. Control theory of digitally networked dynamic systems

    CERN Document Server

    Lunze, Jan


    The book gives an introduction to networked control systems and describes new modeling paradigms, analysis methods for event-driven, digitally networked systems, and design methods for distributed estimation and control. Networked model predictive control is developed as a means to tolerate time delays and packet loss brought about by the communication network. In event-based control the traditional periodic sampling is replaced by state-dependent triggering schemes. Novel methods for multi-agent systems ensure complete or clustered synchrony of agents with identical or with individual dynamic

  11. The Simulation and Study of the Operating System Efficiency Improvement of a Container Terminal


    Liang Di; Wu Shuang; Sun Gui Zhi


    With the rapid expansion of Chinese container terminal throughput, each container terminal increasingly pays attention to the operational efficiency of storage yard. In this paper, aim at the problem of excessive containers relocation assignments to establish the slotting optimization allocation model, and verify the validity of the model by using Matlab; Using tandem queuing network modeling to build model of the container terminal operating system,and simulate the container terminal logisti...

  12. Network management systems for active distribution networks. A feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, D.A.


    A technical feasibility study on network management systems for active distribution networks is reported. The study investigated the potential for modifying a Distribution Network Operator (DNO) Supervisory Control and Data Acquisition System (SCADA) to give some degree of active management. Government incentives have encouraged more and more embedded generation being connected to the UK distribution networks and further acceleration of the process should support the 2010 target for a reduction in emissions of carbon dioxide. The report lists the objectives of the study and summarises what has been achieved; it also discusses limitations, reliability and resilience of existing SCADA. Safety and operational communications are discussed under staff safety and operational safety. Recommendations that could facilitate active management through SCADA are listed, together with suggestions for further study. The work was carried out as part of the DTI New and Renewable Energy Programme managed by Future Energy Solutions.

  13. Network systems and groupware for public facilities; Network system to groupware

    Energy Technology Data Exchange (ETDEWEB)

    Torimaru, K.; Kubo, S. [Fuji Electric Co. Ltd., Tokyo (Japan); Takeda, K. [Osaki Computer Engineering Co. Ltd., Tokyo (Japan)


    This paper outlines solutions for network systems and groupware for the infrastructure of information systems in public facilities. With regard to network systems, Fuji Electric's network solutions including requirements of public facilities and application examples are described. With regard to groupware, the status of groupware used for raising efficiency in public facilities and groupware packages marketed by Fuji Electric. (author)

  14. Spinal Cord Injury Model System Information Network (United States)

    ... the UAB-SCIMS Contact the UAB-SCIMS UAB Spinal Cord Injury Model System Newly Injured Health Daily Living Consumer ... Information Network The University of Alabama at Birmingham Spinal Cord Injury Model System (UAB-SCIMS) maintains this Information Network ...

  15. Computer networks ISE a systems approach

    CERN Document Server

    Peterson, Larry L


    Computer Networks, 4E is the only introductory computer networking book written by authors who have had first-hand experience with many of the protocols discussed in the book, who have actually designed some of them as well, and who are still actively designing the computer networks today. This newly revised edition continues to provide an enduring, practical understanding of networks and their building blocks through rich, example-based instruction. The authors' focus is on the why of network design, not just the specifications comprising today's systems but how key technologies and p

  16. Systemic risk on different interbank network topologies (United States)

    Lenzu, Simone; Tedeschi, Gabriele


    In this paper we develop an interbank market with heterogeneous financial institutions that enter into lending agreements on different network structures. Credit relationships (links) evolve endogenously via a fitness mechanism based on agents' performance. By changing the agent's trust on its neighbor's performance, interbank linkages self-organize themselves into very different network architectures, ranging from random to scale-free topologies. We study which network architecture can make the financial system more resilient to random attacks and how systemic risk spreads over the network. To perturb the system, we generate a random attack via a liquidity shock. The hit bank is not automatically eliminated, but its failure is endogenously driven by its incapacity to raise liquidity in the interbank network. Our analysis shows that a random financial network can be more resilient than a scale free one in case of agents' heterogeneity.

  17. Design and Management of Networked Information Systems

    DEFF Research Database (Denmark)

    Havn, Erling; Bansler, Jørgen P.


    -based IS. There are several reasons for this: (a) Networked IS are large and complex systems; (b) in most cases, one has to deal with a number of existing - probably heterogenous - technical hardware and software platforms and link them together in a network; (c) differences in organizational culture, work......In this paper, we present a newly started research project at the Center for Tele-Information at the Technical University of Denmark. The project focuses on the design and management of networked information systems, that is computer-based IS linked by a wide area network and supporting...... communication between geographically dispersed organizational units. Examples include logistics systems, airline booking systems, and CSCW systems. We assume that the design and implementation of networked IS is significantly more difficult and risky than the development of traditional "stand-alone" computer...


    National Research Council Canada - National Science Library



    ... system.From this last point of view, we will emphasize on the attentional networks theory of Posner, thatproposes different systems to explain diverse aspects of attention, but they are related to each...

  19. Neural network based system for equipment surveillance (United States)

    Vilim, R.B.; Gross, K.C.; Wegerich, S.W.


    A method and system are disclosed for performing surveillance of transient signals of an industrial device to ascertain the operating state. The method and system involves the steps of reading into a memory training data, determining neural network weighting values until achieving target outputs close to the neural network output. If the target outputs are inadequate, wavelet parameters are determined to yield neural network outputs close to the desired set of target outputs and then providing signals characteristic of an industrial process and comparing the neural network output to the industrial process signals to evaluate the operating state of the industrial process. 33 figs.

  20. Seamless integrated network system for wireless communication systems

    NARCIS (Netherlands)

    Wu, Gang; Mizuno, Mitsuhiko; Hase, Yoshihiro; Havinga, Paul J.M.


    To create a network that connects a plurality of wireless communication systems to create optimal systems for various environments, and that seamlessly integrates the resulting systems together in order to provide more efficient and advanced service in general. A network system that can seamlessly

  1. Seamless integrated network system for wireless communication systems

    NARCIS (Netherlands)

    Wu, Gang; Mizuno, Mitsuhiko; Hase, Yoshihiro; Havinga, Paul J.M.


    To create a network that connects a plurality of wireless communication systems to create optimal systems for various environments, and that seamlessly integrates the resulting systems together in order to provide more efficient and advanced service in general. A network system that can seamlessly

  2. The mathematics of networks of linear systems

    CERN Document Server

    Fuhrmann, Paul A


    This book provides the mathematical foundations of networks of linear control systems, developed from an algebraic systems theory perspective. This includes a thorough treatment of questions of controllability, observability, realization theory, as well as feedback control and observer theory. The potential of networks for linear systems in controlling large-scale networks of interconnected dynamical systems could provide insight into a diversity of scientific and technological disciplines. The scope of the book is quite extensive, ranging from introductory material to advanced topics of current research, making it a suitable reference for graduate students and researchers in the field of networks of linear systems. Part I can be used as the basis for a first course in algebraic system theory, while Part II serves for a second, advanced, course on linear systems. Finally, Part III, which is largely independent of the previous parts, is ideally suited for advanced research seminars aimed at preparing graduate ...

  3. Network Physiology: How Organ Systems Dynamically Interact.

    Directory of Open Access Journals (Sweden)

    Ronny P Bartsch

    Full Text Available We systematically study how diverse physiologic systems in the human organism dynamically interact and collectively behave to produce distinct physiologic states and functions. This is a fundamental question in the new interdisciplinary field of Network Physiology, and has not been previously explored. Introducing the novel concept of Time Delay Stability (TDS, we develop a computational approach to identify and quantify networks of physiologic interactions from long-term continuous, multi-channel physiological recordings. We also develop a physiologically-motivated visualization framework to map networks of dynamical organ interactions to graphical objects encoded with information about the coupling strength of network links quantified using the TDS measure. Applying a system-wide integrative approach, we identify distinct patterns in the network structure of organ interactions, as well as the frequency bands through which these interactions are mediated. We establish first maps representing physiologic organ network interactions and discover basic rules underlying the complex hierarchical reorganization in physiologic networks with transitions across physiologic states. Our findings demonstrate a direct association between network topology and physiologic function, and provide new insights into understanding how health and distinct physiologic states emerge from networked interactions among nonlinear multi-component complex systems. The presented here investigations are initial steps in building a first atlas of dynamic interactions among organ systems.

  4. Network Physiology: How Organ Systems Dynamically Interact. (United States)

    Bartsch, Ronny P; Liu, Kang K L; Bashan, Amir; Ivanov, Plamen Ch


    We systematically study how diverse physiologic systems in the human organism dynamically interact and collectively behave to produce distinct physiologic states and functions. This is a fundamental question in the new interdisciplinary field of Network Physiology, and has not been previously explored. Introducing the novel concept of Time Delay Stability (TDS), we develop a computational approach to identify and quantify networks of physiologic interactions from long-term continuous, multi-channel physiological recordings. We also develop a physiologically-motivated visualization framework to map networks of dynamical organ interactions to graphical objects encoded with information about the coupling strength of network links quantified using the TDS measure. Applying a system-wide integrative approach, we identify distinct patterns in the network structure of organ interactions, as well as the frequency bands through which these interactions are mediated. We establish first maps representing physiologic organ network interactions and discover basic rules underlying the complex hierarchical reorganization in physiologic networks with transitions across physiologic states. Our findings demonstrate a direct association between network topology and physiologic function, and provide new insights into understanding how health and distinct physiologic states emerge from networked interactions among nonlinear multi-component complex systems. The presented here investigations are initial steps in building a first atlas of dynamic interactions among organ systems.

  5. Differential network entropy reveals cancer system hallmarks (United States)

    West, James; Bianconi, Ginestra; Severini, Simone; Teschendorff, Andrew E.


    The cellular phenotype is described by a complex network of molecular interactions. Elucidating network properties that distinguish disease from the healthy cellular state is therefore of critical importance for gaining systems-level insights into disease mechanisms and ultimately for developing improved therapies. By integrating gene expression data with a protein interaction network we here demonstrate that cancer cells are characterised by an increase in network entropy. In addition, we formally demonstrate that gene expression differences between normal and cancer tissue are anticorrelated with local network entropy changes, thus providing a systemic link between gene expression changes at the nodes and their local correlation patterns. In particular, we find that genes which drive cell-proliferation in cancer cells and which often encode oncogenes are associated with reductions in network entropy. These findings may have potential implications for identifying novel drug targets. PMID:23150773

  6. Capacity gain with an alternative LTE railway communication network

    DEFF Research Database (Denmark)

    Sniady, Aleksander; Soler, José


    , such as 3GPP Long Term Evolution (LTE). T his paper describe s how to adapt the reversible multi - chain/channel queuing system to model an LTE cell serving ETCS - equipped trains . It is proposed to use the multiple user chains available in the model to represent varying bitrate in LTE radio access network....... Usin g this model , LTE and GSM - R are compare d in terms of capacity on an example at Copenhagen Main Train Station . The purpose of this work is to demonstrate the benefits that railway operators and infrastructure managers can expect from the introduc tion of LTE , as a telecommunication technology...

  7. Process query systems for network security monitoring (United States)

    Berk, Vincent; Fox, Naomi


    In this paper we present the architecture of our network security monitoring infrastructure based on a Process Query System (PQS). PQS offers a new and powerful way of efficiently processing data streams, based on process descriptions that are submitted as queries. In this case the data streams are familiar network sensors, such as Snort, Netfilter, and Tripwire. The process queries describe the dynamics of network attacks and failures, such as worms, multistage attacks, and router failures. Using PQS the task of monitoring enterprise class networks is simplified, offering a priority-based GUI to the security administrator that clearly outlines events that require immediate attention. The PQS-Net system is deployed on an unsecured production network; the system has successfully detected many diverse attacks and failures.

  8. High-speed, intra-system networks

    Energy Technology Data Exchange (ETDEWEB)

    Quinn, Heather M [Los Alamos National Laboratory; Graham, Paul S [Los Alamos National Laboratory; Manuzzato, Andrea [Los Alamos National Laboratory; Fairbanks, Tom [Los Alamos National Laboratory; Dallmann, Nicholas [Los Alamos National Laboratory; Desgeorges, Rose [Los Alamos National Laboratory


    Recently, engineers have been studying on-payload networks for fast communication paths. Using intra-system networks as a means to connect devices together allows for a flexible payload design that does not rely on dedicated communication paths between devices. In this manner, the data flow architecture of the system can be dynamically reconfigured to allow data routes to be optimized for the application or configured to route around devices that are temporarily or permanently unavailable. To use intra-system networks, devices will need network controllers and switches. These devices are likely to be affected by single-event effects, which could affect data communication. In this paper we will present radiation data and performance analysis for using a Broadcom network controller in a neutron environment.

  9. Developing aircraft photonic networks for airplane systems

    DEFF Research Database (Denmark)

    White, Henry J.; Brownjohn, Nick; Baptista, João


    Achieving affordable high speed fiber optic communication networks for airplane systems has proved to be challenging. In this paper we describe a summary of the EU Framework 7 project DAPHNE (Developing Aircraft Photonic Networks). DAPHNE aimed to exploit photonic technology from terrestrial comm...

  10. Network model of security system

    Directory of Open Access Journals (Sweden)

    Adamczyk Piotr


    Full Text Available The article presents the concept of building a network security model and its application in the process of risk analysis. It indicates the possibility of a new definition of the role of the network models in the safety analysis. Special attention was paid to the development of the use of an algorithm describing the process of identifying the assets, vulnerability and threats in a given context. The aim of the article is to present how this algorithm reduced the complexity of the problem by eliminating from the base model these components that have no links with others component and as a result and it was possible to build a real network model corresponding to reality.

  11. The Networking of Interactive Bibliographic Retrieval Systems. (United States)

    Marcus, Richard S.; Reintjes, J. Francis

    Research in networking of heterogeneous interactive bibliographic retrieval systems is being conducted which centers on the concept of a virtual retrieval system. Such a virtual system would be created through a translating computer interface that would provide access to the different retrieval systems and data bases in a uniform and convenient…

  12. Green supply chain management using the queuing theory to handle congestion and reduce energy consumption and emissions from supply chain transportation fleet

    Directory of Open Access Journals (Sweden)

    Arvin Aziziankohan


    Full Text Available Purpose: Nowadays, governments and people pay more attention to use green products due to environmental pollution, irreplaceable energy and shortage of resources. Green products are resulted from the application of green supply chain management strategies to the organizations' performance strategies, so that we can reduce environmental pollutants and wastes and take a step towards saving energy with limited resources. Methodology:  In this paper, the effect of reducing energy consumption in green supply chain is examined by using queuing theory and transportation models. Data was generated and solved by a commercial optimization epackage. Findings:  The findings indicate that suitable assignment of existing transportation fleet with specified capacity, and using queueing theory in a closed-loop network to reduce the queue length and handle congestion, can cause a reduction in energy consumption by optimizing transportation and waiting times in a green supply chain. Originality/value: Adopting investment strategy in improving the environmental performance of the supply chain, will yield in many advantages and benefits. This article investigates the effect of queuing theory on reducing waiting time, optimizing energy consumption in green supply chain, and consequently decreasing pollution.

  13. Network Basic Language Translation System: Security Infrastructure

    National Research Council Canada - National Science Library

    Mittrick, Mark R


    .... The Network Basic Language Translation System (NetBLTS) was proposed and accepted as part of the U.S. Army Research Laboratory's offering of initiatives within the Horizontal Fusion portfolio in 2003...

  14. Network support for system initiated checkpoints (United States)

    Chen, Dong; Heidelberger, Philip


    A system, method and computer program product for supporting system initiated checkpoints in parallel computing systems. The system and method generates selective control signals to perform checkpointing of system related data in presence of messaging activity associated with a user application running at the node. The checkpointing is initiated by the system such that checkpoint data of a plurality of network nodes may be obtained even in the presence of user applications running on highly parallel computers that include ongoing user messaging activity.

  15. Network science, nonlinear science and infrastructure systems

    CERN Document Server


    Network Science, Nonlinear Science and Infrastructure Systems has been written by leading scholars in these areas. Its express purpose is to develop common theoretical underpinnings to better solve modern infrastructural problems. It is felt by many who work in these fields that many modern communication problems, ranging from transportation networks to telecommunications, Internet, supply chains, etc., are fundamentally infrastructure problems. Moreover, these infrastructure problems would benefit greatly from a confluence of theoretical and methodological work done with the areas of Network Science, Dynamical Systems and Nonlinear Science. This book is dedicated to the formulation of infrastructural tools that will better solve these types of infrastructural problems. .

  16. Ethical Issues in Network System Design

    Directory of Open Access Journals (Sweden)

    Duncan Langford


    Full Text Available Today, most desktop computers and PCs are networked that is, they have the ability to link to other machines, usually to access data and other information held remotely. Such machines may sometimes be connected directly to each other, as part of an office or company computer system. More frequently, however, connected machines are at a considerable distance from each other, typically connected through links to global systems such as the Internet, or World Wide Web (WWW. The networked machine itself may be anything from a powerful company computer with direct Internet connections, to a small hobbyist machine, accessing a bulletin board through telephone and modem. It is important to remember that, whatever the type or the location of networked machines, their access to the network, and the network itself, was planned and constructed following deliberate design considerations. In this paper I discuss some ways in which the technical design of computer systems might appropriately be influenced by ethical issues, and examine pressures on computer scientists and others to technically control network related actions perceived as 'unethical'. After examination of the current situation, I draw together the issues, and conclude by suggesting some ethically based recommendations for the future design of networked systems.

  17. Smart Sensor Network System For Environment Monitoring

    Directory of Open Access Journals (Sweden)

    Javed Ali Baloch


    Full Text Available SSN (Smart Sensor Network systems could be used to monitor buildings with modern infrastructure, plant sites with chemical pollution, horticulture, natural habitat, wastewater management and modern transport system. To sense attributes of phenomena and make decisions on the basis of the sensed value is the primary goal of such systems. In this paper a Smart Spatially aware sensor system is presented. A smart system, which could continuously monitor the network to observe the functionality and trigger, alerts to the base station if a change in the system occurs and provide feedback periodically, on demand or even continuously depending on the nature of the application. The results of the simulation trials presented in this paper exhibit the performance of a Smart Spatially Aware Sensor Networks.



    Attila Trohák; Máté Kolozsi-Tóth; Péter Rádi


    In the paper we will introduce an intelligent conveyor surveillance system. We started a research project to design and develop a conveyor surveillance system based on wireless sensor network and GPRS communication. Our system is able to measure temperature on fixed and moving, rotating surfaces and able to detect smoke. We would like to introduce the developed devices and give an application example.

  19. Automated Analysis of Security in Networking Systems

    DEFF Research Database (Denmark)

    Buchholtz, Mikael


    It has for a long time been a challenge to built secure networking systems. One way to counter this problem is to provide developers of software applications for networking systems with easy-to-use tools that can check security properties before the applications ever reach the marked. These tools...... will both help raise the general level of awareness of the problems and prevent the most basic flaws from occurring. This thesis contributes to the development of such tools. Networking systems typically try to attain secure communication by applying standard cryptographic techniques. In this thesis...... attacks, and attacks launched by insiders. Finally, the perspectives for the application of the analysis techniques are discussed, thereby, coming a small step closer to providing developers with easy- to-use tools for validating the security of networking applications....

  20. [Renewal of NIHS computer network system]. (United States)

    Segawa, Katsunori; Nakano, Tatsuya; Saito, Yoshiro


    Updated version of National Institute of Health Sciences Computer Network System (NIHS-NET) is described. In order to reduce its electric power consumption, the main server system was newly built using the virtual machine technology. The service that each machine provided in the previous network system should be maintained as much as possible. Thus, the individual server was constructed for each service, because a virtual server often show decrement in its performance as compared with a physical server. As a result, though the number of virtual servers was increased and the network communication became complicated among the servers, the conventional service was able to be maintained, and security level was able to be rather improved, along with saving electrical powers. The updated NIHS-NET bears multiple security countermeasures. To maximal use of these measures, awareness for the network security by all users is expected.

  1. Design and Realization of Network Teaching System

    Directory of Open Access Journals (Sweden)

    Ji Shan Shan


    Full Text Available Since 21 century, with the wide spread in family and public, network has been applied in many new fields, and the application in classes is of no exception. In traditional education, teachers give lessons to students face to face. Hence, the teaching quality depends largely on the quality and initiative of the individual teacher. However, the serious disadvantages of this mode are that teachers completely dominate the classroom and may ignore the subjective cognition role of the students, which may be bad for the growth of creativity and the innovative thinking ability. Obviously, traditional education mode cannot meet the requirements of the this new era which leads to the booming developing tendency of the network. As a new teaching measure, scientifically combining modern information technology and teaching practice, network teaching not only changes the traditional education by the means and form, but even also gives new meanings to teaching concept, process, method as well as teacher-student role and other deep levels. With the help of network teaching system, on-line classroom learning, relevant information systematization, standardization and automation, this system provides students with an efficient online learning method with high quality. This also helps to solve the disadvantages of the traditional teaching mode and promote the teaching methods to a new stage. It improves the network teaching platform, enriches the network teaching resources, and establishes a network teaching system, so as to improve information quality of teachers and students and assist in improving teaching quality of schools.

  2. Cross Layer Analysis of P2MP Hybrid FSO/RF Network

    KAUST Repository

    Rakia, Tamer


    This paper presents and analyzes a point-tomultipoint (P2MP) network that uses a number of freespace optical (FSO) links for data transmission from the central node to the different remote nodes of the network. A common backup radio frequency (RF) link can be used by the central node for data transmission to any remote node in case any one of the FSO links fails. Each remote node is assigned a transmit buffer at the central node. Considering the transmission link from the central node to a tagged remote node, we study various performance metrics. Specifically,we study the throughput from the central node to the tagged node, the average transmit buffer size, the symbol queuing delay in the transmit buffer, the efficiency of the queuing system, the symbol loss probability, and the RF link utilization. Numerical examples are presented to compare the performance of the proposed P2MP hybrid FSO/RF network with that of a P2MP FSO-only network and show that the P2MP hybrid FSO/RF network achieves considerable performance improvement over the P2MP FSO-only network.

  3. Spatial Models and Networks of Living Systems

    DEFF Research Database (Denmark)

    Juul, Jeppe Søgaard

    When studying the dynamics of living systems, insight can often be gained by developing a mathematical model that can predict future behaviour of the system or help classify system characteristics. However, in living cells, organisms, and especially groups of interacting individuals, a large number....... Such systems are known to be stabilized by spatial structure. Finally, I analyse data from a large mobile phone network and show that people who are topologically close in the network have similar communication patterns. This main part of the thesis is based on six different articles, which I have co...

  4. Reconfigurable radio systems network architectures and standards

    CERN Document Server

    Iacobucci, Maria Stella


    This timely book provides a standards-based view of the development, evolution, techniques and potential future scenarios for the deployment of reconfigurable radio systems.  After an introduction to radiomobile and radio systems deployed in the access network, the book describes cognitive radio concepts and capabilities, which are the basis for reconfigurable radio systems.  The self-organizing network features introduced in 3GPP standards are discussed and IEEE 802.22, the first standard based on cognitive radio, is described. Then the ETSI reconfigurable radio systems functional ar

  5. Deterministic System Identification Using RBF Networks

    Directory of Open Access Journals (Sweden)

    Joilson Batista de Almeida Rego


    Full Text Available This paper presents an artificial intelligence application using a nonconventional mathematical tool: the radial basis function (RBF networks, aiming to identify the current plant of an induction motor or other nonlinear systems. Here, the objective is to present the RBF response to different nonlinear systems and analyze the obtained results. A RBF network is trained and simulated in order to obtain the dynamical solution with basin of attraction and equilibrium point for known and unknown system and establish a relationship between these dynamical systems and the RBF response. On the basis of several examples, the results indicating the effectiveness of this approach are demonstrated.

  6. Design of RFID Cloud Services in a Low Bandwidth Network Environment

    Directory of Open Access Journals (Sweden)

    John P.T. Mo


    Full Text Available The use of Information and Communication Technologies has significantly improved the efficiency of modern supply chains. Existing IT architecture is too rigid to allow new technologies such as RFID technologies to be implemented. With the aid of virtualisation and integrated with cloud services, infrastructure hardware and network devices can be consolidated into a physical device, reducing the cost of ownership. However, for such cloud services model to work correctly, a high speed network is required between each site and the cloud service provider. This poses huge challenges for real‐time system such as RFID‐enabled supply chains. Since modern supply chains operate on a global platform, it is almost impossible to assure availability of high speed networks across the global supply chain. This paper proposes two solutions to supplement the virtualisation and cloud services model. A sub‐cloud services solution, where each service is distributed across multiple hosts across different countries and regions is proposed to enhance accessibility to higher bandwidth networks. The second solution is the Queued Burst Device Compression system incorporates a compression service that compresses RFID data sets into much smaller packages. This solution is proved to work by a multiple‐in‐single‐out queuing model and is suitable for low bandwidth networks such as GPRS and 3G wireless environmenst.

  7. A network-based dynamical ranking system

    CERN Document Server

    Motegi, Shun


    Ranking players or teams in sports is of practical interests. From the viewpoint of networks, a ranking system is equivalent a centrality measure for sports networks, whereby a directed link represents the result of a single game. Previously proposed network-based ranking systems are derived from static networks, i.e., aggregation of the results of games over time. However, the score (i.e., strength) of a player, for example, depends on time. Defeating a renowned player in the peak performance is intuitively more rewarding than defeating the same player in other periods. To account for this factor, we propose a dynamic variant of such a network-based ranking system and apply it to professional men's tennis data. Our ranking system, also interpreted as a centrality measure for directed temporal networks, has two parameters. One parameter represents the exponential decay rate of the past score, and the other parameter controls the effect of indirect wins on the score. We derive a set of linear online update equ...

  8. Mathematical analysis of single queue multi server and multi queue multi server queuing models: comparison study


    Vijay Prasad; Badshah V.H; Tariq Ahmad Koka


    In the research paper entitled Mathematical Analysis of Single Queue Multi Server and Multi Queue Multi Server Queuing Model, Prasad and Badshah [7] were proved that single queue multi server model is better than multi queue multi server model, and discussed the relation between the performance measures of these two models, and derive the mathematical equations. In this paper we derive the total cost with assumption of certain Waiting cost in both cases. Also, prove that the expected total co...

  9. Modeling and dimensioning of the resources in a delivery restaurant chain using queuing theory


    Ontiveros López, Guillem


    Using queuing theory, resources available at a delivery restaurant are studied and related wirh the quality of service En este proyecto, se estudia la relación entre las variables de calidad del servicio y los recursos disponibles en un restaurante de comida a domicili usando teoria de colas Usant teoria de cues, en aquest projecte es relacionen les variables de la qualitat del servei amb els recursos disponibles a una unitat de negoci

  10. A system for routing and capacity assignment in computer communication networks (United States)

    Gavish, Bezalel; Neuman, Irina


    The combined problem of selecting a primary route for each communicating pair and a capacity value for each link in computer communication networks is considered. The network topology and traffic characteristics are given: a set of candidate routes and of candidate capacities for each link are also available. The goal is to obtain the least costly feasible design where the costs include both capacity and queuing components. Lagrangean relaxation and subgradient optimization techniques were used to obtain verifiable solutions to the problem. The method was tested on several topologies, and in all cases good feasible solutions, as well as tight lower bounds, were obtained. The model can be generalized to deal with different classes of customers, characterized by different priorities, message lengths, and/or delay requirements.

  11. Network Management using Multi-Agents System

    Directory of Open Access Journals (Sweden)

    Nestor DUQUE


    Full Text Available This paper aims to present a multiagent system for network management. The models developed for the proposed system defines certain intelligent agents interact to achieve the objectives and requirements of the multiagent organization.These agents have the property of being adaptive, acquire knowledge and skills to make decisions according to the actual state of the network that is represented in the information base, MIB, SNMP devices. The ideal state of the network policy is defined by the end user entered, which contain the value that should have performance variables and other parameters such as the frequency with which these variables should be monitored.. An agent based architecture increase the integration, adaptability, cooperation, autonomy and the efficient operation in heterogeneous environment in the network supervision. 

  12. Network Management using Multi-Agents System

    Directory of Open Access Journals (Sweden)

    Gustavo ISAZA


    Full Text Available This paper aims to present a multiagent system for network management. The models developed for the proposed system defines certain intelligent agents interact to achieve the objectives and requirements of the multiagent organization.These agents have the property of being adaptive, acquire knowledge and skills to make decisions according to the actual state of the network that is represented in the information base, MIB, SNMP devices. The ideal state of the network policy is defined by the end user entered, which contain the value that should have performance variables and other parameters such as the frequency with which these variables should be monitored.. An agent based architecture increase the integration, adaptability, cooperation, autonomy and the efficient operation in heterogeneous environment in the network supervision. 

  13. Analisa Perbandingan Quality of Service Voice Over IP dengan Pengujian Codec Menggunakan Algoritma Low Latency Queuing

    Directory of Open Access Journals (Sweden)

    Darmawan Darmawan


    Full Text Available Voice over IP (VoIP adalah solusi komunikasi suara yang murah karena menggunakan jaringan IP dibanding penggunaan telephone analog yang banyak memakan biaya. Dalam penerapannya, VoIP mengalami permasalahan karena menggunakan teknologi packet switching yang mana penggunaannya bersamaan dengan paket data sehingga timbul delay, jitter, dan packet loss.  Pada penelitian ini, algoritma Low Latency Queuing (LLQ diterapkan pada router cisco. Algoritma LLQ merupakan gabungan dari algoritma Priority Queuing (PQ dan Class Based Weight Fair Queuing (CBWFQ sehingga dapat memprioritaskan paket suara disamping paket data. Algoritma LLQ ini diujikan menggunakan codec GSM FR, G722, dan G711 A-law. Hasil pengujian didapatkan nilai parameter yang tidak jauh berbeda dan memenuhi standar ITU-T.G1010. Nilai delay rata - rata terendah yaitu ketika menggunakan codec G722 sebesar 20,019 ms tetapi G722 memiliki rata - rata jitter yang terbesar yaitu 0,986 ms.  Codec dengan jitter rata – rata terkecil adalah G711 A-law sebesar 0,838 ms. Packet loss untuk semua codec yang diujikan adalah 0%.  Throughput pada paket data terbesar saat menggunakan codec GSM FR yaitu 18,139 kbps. Codec yang direkomendasikan adalah G711 A-law karena lebih stabil dari segi jitter dan codec GSM FR cocok diimplementasikan pada jaringan yang memiliki bandwitdh kecil.

  14. Sampled fiber grating for WDM signal queuing with picosecond time interval (United States)

    Zhao, Weiqian; Liu, Shuai; Qi, Haifeng; Peng, Gangding; Shen, Mingya


    A new sampled fiber grating scheme is investigated for WDM signal queuing in time domain. The queuing is aimed at achieving very short constant time intervals down to picoseconds (ps) for many wavelength channels by a single fiber device. Theory and modeling predict that a consistence of linear spectral profiles exists between reflectivity or transmission spectrum and time delay spectrum. A sampled fiber grating based on Gaussian beam writing is proposed to offer a large number of wavelength channels and time delays within an approximate linear profile. Results for simulating a Gaussian sampled fiber grating show that the time delay minima of 8 channels within a section of the spectral profile have an average time delay step of 2.83 ps and standard deviation of 7.4% from linearity. Fiber gratings were successfully written by Gaussian laser beam in fabrication. A Gaussian sampled fiber grating was measured for time delay spectrum of 4 wavelength channels. An average time delay step of 9.67 ps is obtained. Some issues and related analysis and discussion are given. Our preliminary experiment suggests that the sampled fiber grating scheme can achieve ps-time steps for WDM signal queuing such as high-resolution time delay lines.

  15. Understanding Supply Networks from Complex Adaptive Systems

    Directory of Open Access Journals (Sweden)

    Jamur Johnas Marchi


    Full Text Available This theoretical paper is based on complex adaptive systems (CAS that integrate dynamic and holistic elements, aiming to discuss supply networks as complex systems and their dynamic and co-evolutionary processes. The CAS approach can give clues to understand the dynamic nature and co-evolution of supply networks because it consists of an approach that incorporates systems and complexity. This paper’s overall contribution is to reinforce the theoretical discussion of studies that have addressed supply chain issues, such as CAS.

  16. Decomposability queueing and computer system applications

    CERN Document Server

    Courtois, P J


    Decomposability: Queueing and Computer System Applications presents a set of powerful methods for systems analysis. This 10-chapter text covers the theory of nearly completely decomposable systems upon which specific analytic methods are based.The first chapters deal with some of the basic elements of a theory of nearly completely decomposable stochastic matrices, including the Simon-Ando theorems and the perturbation theory. The succeeding chapters are devoted to the analysis of stochastic queuing networks that appear as a type of key model. These chapters also discuss congestion problems in

  17. Rational positive systems for reaction networks

    NARCIS (Netherlands)

    J.H. van Schuppen (Jan)


    textabstractThe purpose of the lecture associated with this paper is to present problems, concepts, and theorems of control and system theory for a subclass of the rational positive systems of which examples have been published as models of biochemical cell reaction networks. The recent advances in

  18. Designing Networked Adaptive Interactive Hybrid Systems

    NARCIS (Netherlands)

    Kester, L.J.H.M.


    Advances in network technologies enable distributed systems, operating in complex physical environments, to coordinate their activities over larger areas within shorter time intervals. In these systems humans and intelligent machines will, in close interaction, be able to reach their goals under

  19. Evaluating neural networks and artificial intelligence systems (United States)

    Alberts, David S.


    Systems have no intrinsic value in and of themselves, but rather derive value from the contributions they make to the missions, decisions, and tasks they are intended to support. The estimation of the cost-effectiveness of systems is a prerequisite for rational planning, budgeting, and investment documents. Neural network and expert system applications, although similar in their incorporation of a significant amount of decision-making capability, differ from each other in ways that affect the manner in which they can be evaluated. Both these types of systems are, by definition, evolutionary systems, which also impacts their evaluation. This paper discusses key aspects of neural network and expert system applications and their impact on the evaluation process. A practical approach or methodology for evaluating a certain class of expert systems that are particularly difficult to measure using traditional evaluation approaches is presented.

  20. Pinning control of complex networked systems synchronization, consensus and flocking of networked systems via pinning

    CERN Document Server

    Su, Housheng


    Synchronization, consensus and flocking are ubiquitous requirements in networked systems. Pinning Control of Complex Networked Systems investigates these requirements by using the pinning control strategy, which aims to control the whole dynamical network with huge numbers of nodes by imposing controllers for only a fraction of the nodes. As the direct control of every node in a dynamical network with huge numbers of nodes might be impossible or unnecessary, it’s then very important to use the pinning control strategy for the synchronization of complex dynamical networks. The research on pinning control strategy in consensus and flocking of multi-agent systems can not only help us to better understand the mechanisms of natural collective phenomena, but also benefit applications in mobile sensor/robot networks. This book offers a valuable resource for researchers and engineers working in the fields of control theory and control engineering.   Housheng Su is an Associate Professor at the Department of Contro...

  1. Dynamical systems on networks a tutorial

    CERN Document Server

    Porter, Mason A


    This volume is a tutorial for the study of dynamical systems on networks. It discusses both methodology and models, including spreading models for social and biological contagions. The authors focus especially on “simple” situations that are analytically tractable, because they are insightful and provide useful springboards for the study of more complicated scenarios. This tutorial, which also includes key pointers to the literature, should be helpful for junior and senior undergraduate students, graduate students, and researchers from mathematics, physics, and engineering who seek to study dynamical systems on networks but who may not have prior experience with graph theory or networks. Mason A. Porter is Professor of Nonlinear and Complex Systems at the Oxford Centre for Industrial and Applied Mathematics, Mathematical Institute, University of Oxford, UK. He is also a member of the CABDyN Complexity Centre and a Tutorial Fellow of Somerville College. James P. Gleeson is Professor of Industrial and Appli...

  2. Network analysis of eight industrial symbiosis systems (United States)

    Zhang, Yan; Zheng, Hongmei; Shi, Han; Yu, Xiangyi; Liu, Gengyuan; Su, Meirong; Li, Yating; Chai, Yingying


    Industrial symbiosis is the quintessential characteristic of an eco-industrial park. To divide parks into different types, previous studies mostly focused on qualitative judgments, and failed to use metrics to conduct quantitative research on the internal structural or functional characteristics of a park. To analyze a park's structural attributes, a range of metrics from network analysis have been applied, but few researchers have compared two or more symbioses using multiple metrics. In this study, we used two metrics (density and network degree centralization) to compare the degrees of completeness and dependence of eight diverse but representative industrial symbiosis networks. Through the combination of the two metrics, we divided the networks into three types: weak completeness, and two forms of strong completeness, namely "anchor tenant" mutualism and "equality-oriented" mutualism. The results showed that the networks with a weak degree of completeness were sparse and had few connections among nodes; for "anchor tenant" mutualism, the degree of completeness was relatively high, but the affiliated members were too dependent on core members; and the members in "equality-oriented" mutualism had equal roles, with diverse and flexible symbiotic paths. These results revealed some of the systems' internal structure and how different structures influenced the exchanges of materials, energy, and knowledge among members of a system, thereby providing insights into threats that may destabilize the network. Based on this analysis, we provide examples of the advantages and effectiveness of recent improvement projects in a typical Chinese eco-industrial park (Shandong Lubei).

  3. Strategic Investment in Protection in Networked Systems

    CERN Document Server

    Leduc, Matt V


    We study the incentives that agents have to invest in costly protection against cascading failures in networked systems. Applications include vaccination, computer security and airport security. Agents are connected through a network and can fail either intrinsically or as a result of the failure of a subset of their neighbors. We characterize the equilibrium based on an agent's failure probability and derive conditions under which equilibrium strategies are monotone in degree (i.e. in how connected an agent is on the network). We show that different kinds of applications (e.g. vaccination, airport security) lead to very different equilibrium patterns of investments in protection, with important welfare and risk implications. Our equilibrium concept is flexible enough to allow for comparative statics in terms of network properties and we show that it is also robust to the introduction of global externalities (e.g. price feedback, congestion).

  4. VSAT networks in the INTELSAT system (United States)

    Albuquerque, Jose P. A.; Buchsbaum, Luiz M.; Meulman, Christopher B.; Rieger, Frederic; Zhu, Xiaobo


    This paper describes how VSAT networks currently operate in the INTELSAT system. Four classes of VSAT networks (data transaction; circuit-switched; data distribution; microterminals) are identified, and it is verified that all of them can operate with INTELSAT satellites. Most VSAT networks in operation on INTELSAT today operate in fractional transponder leases. Fractional transponder capacity estimates are presented for a wide range of scenarios and different INTELSAT satellite series. These estimates clearly show increasing bandwidth utilization efficiencies for newer generations of INTELSAT satellites. Provided that VSAT and hub sizes are appropriately selected, efficiencies are already significant with existing satellites. Two possible ways of increasing the utilization of satellite resources are examined in the paper: demand assignment multiple access (DAMA) and multiple channel-per-carrier (MCPC) techniques. The impact of using DAMA in circuit-switched VSAT networks is quantified.

  5. Advanced mobile networking, sensing, and controls.

    Energy Technology Data Exchange (ETDEWEB)

    Feddema, John Todd; Kilman, Dominique Marie; Byrne, Raymond Harry; Young, Joseph G.; Lewis, Christopher L.; Van Leeuwen, Brian P.; Robinett, Rush D. III; Harrington, John J.


    This report describes an integrated approach for designing communication, sensing, and control systems for mobile distributed systems. Graph theoretic methods are used to analyze the input/output reachability and structural controllability and observability of a decentralized system. Embedded in each network node, this analysis will automatically reconfigure an ad hoc communication network for the sensing and control task at hand. The graph analysis can also be used to create the optimal communication flow control based upon the spatial distribution of the network nodes. Edge coloring algorithms tell us that the minimum number of time slots in a planar network is equal to either the maximum number of adjacent nodes (or degree) of the undirected graph plus some small number. Therefore, the more spread out that the nodes are, the fewer number of time slots are needed for communication, and the smaller the latency between nodes. In a coupled system, this results in a more responsive sensor network and control system. Network protocols are developed to propagate this information, and distributed algorithms are developed to automatically adjust the number of time slots available for communication. These protocols and algorithms must be extremely efficient and only updated as network nodes move. In addition, queuing theory is used to analyze the delay characteristics of Carrier Sense Multiple Access (CSMA) networks. This report documents the analysis, simulation, and implementation of these algorithms performed under this Laboratory Directed Research and Development (LDRD) effort.

  6. Social Network Supported Process Recommender System (United States)

    Ye, Yanming; Yin, Jianwei; Xu, Yueshen


    Process recommendation technologies have gained more and more attention in the field of intelligent business process modeling to assist the process modeling. However, most of the existing technologies only use the process structure analysis and do not take the social features of processes into account, while the process modeling is complex and comprehensive in most situations. This paper studies the feasibility of social network research technologies on process recommendation and builds a social network system of processes based on the features similarities. Then, three process matching degree measurements are presented and the system implementation is discussed subsequently. Finally, experimental evaluations and future works are introduced. PMID:24672309

  7. Restaurant Management System Over Private Network

    Directory of Open Access Journals (Sweden)

    Amanat Dhillon


    Full Text Available Restaurant Management System over Private Network is an automated business environment which allows restaurants to reduce operational costs increase efficiency of business improve customer satisfaction cut down labour costs decrease order processing time and provide better Quality-of-ServiceQ-S. This system manages a digital menu allowing the customers to place orders easily. Authentication fields for employees enable better administration of the restaurant. The whole restaurant is integrated into one private network thereby improving security and eliminating the need for a constant internet connection.

  8. Preliminary AFBITS Network Control System (United States)


    divided into time slots. This provides essentially simultaneous digital data service to a large number of individual subscribers. In a normal...model telephone switch, modern exchanges such as those developed by the Bell System or the independent Telco suppliers give a good indication of

  9. Evolution of Linux operating system network (United States)

    Xiao, Guanping; Zheng, Zheng; Wang, Haoqin


    Linux operating system (LOS) is a sophisticated man-made system and one of the most ubiquitous operating systems. However, there is little research on the structure and functionality evolution of LOS from the prospective of networks. In this paper, we investigate the evolution of the LOS network. 62 major releases of LOS ranging from versions 1.0 to 4.1 are modeled as directed networks in which functions are denoted by nodes and function calls are denoted by edges. It is found that the size of the LOS network grows almost linearly, while clustering coefficient monotonically decays. The degree distributions are almost the same: the out-degree follows an exponential distribution while both in-degree and undirected degree follow power-law distributions. We further explore the functionality evolution of the LOS network. It is observed that the evolution of functional modules is shown as a sequence of seven events (changes) succeeding each other, including continuing, growth, contraction, birth, splitting, death and merging events. By means of a statistical analysis of these events in the top 4 largest components (i.e., arch, drivers, fs and net), it is shown that continuing, growth and contraction events occupy more than 95% events. Our work exemplifies a better understanding and describing of the dynamics of LOS evolution.

  10. Social networks as embedded complex adaptive systems. (United States)

    Benham-Hutchins, Marge; Clancy, Thomas R


    As systems evolve over time, their natural tendency is to become increasingly more complex. Studies in the field of complex systems have generated new perspectives on management in social organizations such as hospitals. Much of this research appears as a natural extension of the cross-disciplinary field of systems theory. This is the 15th in a series of articles applying complex systems science to the traditional management concepts of planning, organizing, directing, coordinating, and controlling. In this article, the authors discuss healthcare social networks as a hierarchy of embedded complex adaptive systems. The authors further examine the use of social network analysis tools as a means to understand complex communication patterns and reduce medical errors.

  11. The Deep Space Network Advanced Systems Program (United States)

    Davarian, Faramaz


    The deep space network (DSN)--with its three complexes in Goldstone, California, Madrid, Spain, and Canberra, Australia--provides the resources to track and communicate with planetary and deep space missions. Each complex consists of an array of capabilities for tracking probes almost anywhere in the solar system. A number of innovative hardware, software and procedural tools are used for day-to-day operations at DSN complexes as well as at the network control at the Jet Propulsion Laboratory (JPL). Systems and technologies employed by the network include large-aperture antennas (34-m and 70-m), cryogenically cooled receivers, high-power transmitters, stable frequency and timing distribution assemblies, modulation and coding schemes, spacecraft transponders, radiometric tracking techniques, etc. The DSN operates at multiple frequencies, including the 2-GHz band, the 7/8-GHz band, and the 32/34-GHz band.

  12. Embedded systems handbook networked embedded systems

    CERN Document Server

    Zurawski, Richard


    Considered a standard industry resource, the Embedded Systems Handbook provided researchers and technicians with the authoritative information needed to launch a wealth of diverse applications, including those in automotive electronics, industrial automated systems, and building automation and control. Now a new resource is required to report on current developments and provide a technical reference for those looking to move the field forward yet again. Divided into two volumes to accommodate this growth, the Embedded Systems Handbook, Second Edition presents a comprehensive view on this area

  13. Advances in network systems architectures, security, and applications

    CERN Document Server

    Awad, Ali; Furtak, Janusz; Legierski, Jarosław


    This book provides the reader with a comprehensive selection of cutting–edge algorithms, technologies, and applications. The volume offers new insights into a range of fundamentally important topics in network architectures, network security, and network applications. It serves as a reference for researchers and practitioners by featuring research contributions exemplifying research done in the field of network systems. In addition, the book highlights several key topics in both theoretical and practical aspects of networking. These include wireless sensor networks, performance of TCP connections in mobile networks, photonic data transport networks, security policies, credentials management, data encryption for network transmission, risk management, live TV services, and multicore energy harvesting in distributed systems. .

  14. Controllable Buoys and Networked Buoy Systems (United States)

    Davoodi, Faranak (Inventor); Davoudi, Farhooman (Inventor)


    Buoyant sensor networks are described, comprising floating buoys with sensors and energy harvesting capabilities. The buoys can control their buoyancy and motion, and can organize communication in a distributed fashion. Some buoys may have tethered underwater vehicles with a smart spooling system that allows the vehicles to dive deep underwater while remaining in communication and connection with the buoys.

  15. Comprehensive information system development and networking in ...

    African Journals Online (AJOL)

    Background/Aim: Hospital Information System(HIS) and Networking development is now the most important technology that must be embraced by all hospitals and clinics these days. Patients sometimes used to face problems in order to have quick and good services in the hospitals, often due to delay in searching for the ...

  16. Social network based dynamic transit service through the OMITS system. (United States)


    The Open Mode Integrated Transportation System (OMITS) forms a sustainable information infrastructure for communication within and between the mobile/Internet network, the roadway : network, and the users social network. It manipulates the speed g...

  17. Network and adaptive system of systems modeling and analysis.

    Energy Technology Data Exchange (ETDEWEB)

    Lawton, Craig R.; Campbell, James E. Dr. (.; .); Anderson, Dennis James; Eddy, John P.


    This report documents the results of an LDRD program entitled ''Network and Adaptive System of Systems Modeling and Analysis'' that was conducted during FY 2005 and FY 2006. The purpose of this study was to determine and implement ways to incorporate network communications modeling into existing System of Systems (SoS) modeling capabilities. Current SoS modeling, particularly for the Future Combat Systems (FCS) program, is conducted under the assumption that communication between the various systems is always possible and occurs instantaneously. A more realistic representation of these communications allows for better, more accurate simulation results. The current approach to meeting this objective has been to use existing capabilities to model network hardware reliability and adding capabilities to use that information to model the impact on the sustainment supply chain and operational availability.

  18. Design Criteria For Networked Image Analysis System (United States)

    Reader, Cliff; Nitteberg, Alan


    Image systems design is currently undergoing a metamorphosis from the conventional computing systems of the past into a new generation of special purpose designs. This change is motivated by several factors, notably among which is the increased opportunity for high performance with low cost offered by advances in semiconductor technology. Another key issue is a maturing in understanding of problems and the applicability of digital processing techniques. These factors allow the design of cost-effective systems that are functionally dedicated to specific applications and used in a utilitarian fashion. Following an overview of the above stated issues, the paper presents a top-down approach to the design of networked image analysis systems. The requirements for such a system are presented, with orientation toward the hospital environment. The three main areas are image data base management, viewing of image data and image data processing. This is followed by a survey of the current state of the art, covering image display systems, data base techniques, communications networks and software systems control. The paper concludes with a description of the functional subystems and architectural framework for networked image analysis in a production environment.

  19. Locomotive monitoring system using wireless sensor networks

    CSIR Research Space (South Africa)

    Croucamp, PL


    Full Text Available Conference on Industrial Informatics (INDIN), 27-30 July 2014 Locomotive monitoring system using wireless sensor networks P. L. Croucamp1, S. Rimer1 and C. Kruger2 1Department of Electrical and Electronic Engineering University of Johannesburg... Johannesburg, South Africa Email: 2Advanced Sensor Networks, Meraka. CSIR Pretoria, South Africa Email: Abstract Theft of cables used for powering a locomotive not only stops the train from functioning but also...

  20. A Knowledge Management System Using Bayesian Networks (United States)

    Ribino, Patrizia; Oliveri, Antonio; Re, Giuseppe Lo; Gaglio, Salvatore

    In today's world, decision support and knowledge management processes are strategic and interdependent activities in many organizations. The companies' interest on a correct knowledge management is grown, more than interest on the mere knowledge itself. This paper proposes a Knowledge Management System based on Bayesian networks. The system has been tested collecting and using data coming from projects and processes typical of ICT companies, and provides a Document Management System and a Decision Support system to share documents and to plan how to best use firms' knowledge.

  1. Wireless Sensor Network Based Smart Parking System

    Directory of Open Access Journals (Sweden)

    Jeffrey JOSEPH


    Full Text Available Ambient Intelligence is a vision in which various devices come together and process information from multiple sources in order to exert control on the physical environment. In addition to computation and control, communication plays a crucial role in the overall functionality of such a system. Wireless Sensor Networks are one such class of networks, which meet these criteria. These networks consist of spatially distributed sensor motes which work in a co-operative manner to sense and control the environment. In this work, an implementation of an energy-efficient and cost-effective, wireless sensor networks based vehicle parking system for a multi-floor indoor parking facility has been introduced. The system monitors the availability of free parking slots and guides the vehicle to the nearest free slot. The amount of time the vehicle has been parked is monitored for billing purposes. The status of the motes (dead/alive is also recorded. Information like slot allocated, directions to the slot and billing data is sent as a message to customer’s mobile phones. This paper extends our previous work 1 with the development of a low cost sensor mote, about one tenth the cost of a commercially available mote, keeping in mind the price sensitive markets of the developing countries.

  2. Reaction networks and kinetics of biochemical systems. (United States)

    Arceo, Carlene Perpetua P; Jose, Editha C; Lao, Angelyn R; Mendoza, Eduardo R


    This paper further develops the connection between Chemical Reaction Network Theory (CRNT) and Biochemical Systems Theory (BST) that we recently introduced [1]. We first use algebraic properties of kinetic sets to study the set of complex factorizable kinetics CFK(N) on a CRN, which shares many characteristics with its subset of mass action kinetics. In particular, we extend the Theorem of Feinberg-Horn [9] on the coincidence of the kinetic and stoichiometric subsets of a mass action system to CF kinetics, using the concept of span surjectivity. We also introduce the branching type of a network, which determines the availability of kinetics on it and allows us to characterize the networks for which all kinetics are complex factorizable: A "Kinetics Landscape" provides an overview of kinetics sets, their algebraic properties and containment relationships. We then apply our results and those (of other CRNT researchers) reviewed in [1] to fifteen BST models of complex biological systems and discover novel network and kinetic properties that so far have not been widely studied in CRNT. In our view, these findings show an important benefit of connecting CRNT and BST modeling efforts. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Large deviations for Gaussian queues modelling communication networks

    CERN Document Server

    Mandjes, Michel


    Michel Mandjes, Centre for Mathematics and Computer Science (CWI) Amsterdam, The Netherlands, and Professor, Faculty of Engineering, University of Twente. At CWI Mandjes is a senior researcher and Director of the Advanced Communications Network group.  He has published for 60 papers on queuing theory, networks, scheduling, and pricing of networks.

  4. Modeling Human Supervisory Control in Heterogeneous Unmanned Vehicle Systems (United States)


    events through a queue, nominally due to another queue having reached its capacity limitation (Balsamo, Persone, & Onvural, 2001; Onvural, 1990; Perros ...Communication and Coordination, Athens, Greece. Perros , H. G. (1984). Queuing Networks with Blocking: A Bibliography. ACM Sigmetrics, Performance Evaluation

  5. Situational Awareness of Network System Roles (SANSR)

    Energy Technology Data Exchange (ETDEWEB)

    Huffer, Kelly M [ORNL; Reed, Joel W [ORNL


    In a large enterprise it is difficult for cyber security analysts to know what services and roles every machine on the network is performing (e.g., file server, domain name server, email server). Using network flow data, already collected by most enterprises, we developed a proof-of-concept tool that discovers the roles of a system using both clustering and categorization techniques. The tool's role information would allow cyber analysts to detect consequential changes in the network, initiate incident response plans, and optimize their security posture. The results of this proof-of-concept tool proved to be quite accurate on three real data sets. We will present the algorithms used in the tool, describe the results of preliminary testing, provide visualizations of the results, and discuss areas for future work. Without this kind of situational awareness, cyber analysts cannot quickly diagnose an attack or prioritize remedial actions.

  6. Architecture for networked electronic patient record systems. (United States)

    Takeda, H; Matsumura, Y; Kuwata, S; Nakano, H; Sakamoto, N; Yamamoto, R


    There have been two major approaches to the development of networked electronic patient record (EPR) architecture. One uses object-oriented methodologies for constructing the model, which include the GEHR project, Synapses, HL7 RIM and so on. The second approach uses document-oriented methodologies, as applied in examples of HL7 PRA. It is practically beneficial to take the advantages of both approaches and to add solution technologies for network security such as PKI. In recognition of the similarity with electronic commerce, a certificate authority as a trusted third party will be organised for establishing networked EPR system. This paper describes a Japanese functional model that has been developed, and proposes a document-object-oriented architecture, which is-compared with other existing models.

  7. Gas Main Sensor and Communications Network System

    Energy Technology Data Exchange (ETDEWEB)

    Hagen Schempf


    Automatika, Inc. was contracted by the Department of Energy (DOE) and with co-funding from the Northeast Gas Association (NGA), to develop an in-pipe natural gas prototype measurement and wireless communications system for assessing and monitoring distribution networks. This projected was completed in April 2006, and culminated in the installation of more than 2 dozen GasNet nodes in both low- and high-pressure cast-iron and steel mains owned by multiple utilities in the northeastern US. Utilities are currently logging data (off-line) and monitoring data in real time from single and multiple networked sensors over cellular networks and collecting data using wireless bluetooth PDA systems. The system was designed to be modular, using in-pipe sensor-wands capable of measuring, flow, pressure, temperature, water-content and vibration. Internal antennae allowed for the use of the pipe-internals as a waveguide for setting up a sensor network to collect data from multiple nodes simultaneously. Sensor nodes were designed to be installed with low- and no-blow techniques and tools. Using a multi-drop bus technique with a custom protocol, all electronics were designed to be buriable and allow for on-board data-collection (SD-card), wireless relaying and cellular network forwarding. Installation options afforded by the design included direct-burial and external polemounted variants. Power was provided by one or more batteries, direct AC-power (Class I Div.2) and solar-array. The utilities are currently in a data-collection phase and intend to use the collected (and processed) data to make capital improvement decisions, compare it to Stoner model predictions and evaluate the use of such a system for future expansion, technology-improvement and commercialization starting later in 2006.

  8. Structural systems identification of genetic regulatory networks. (United States)

    Xiong, Hao; Choe, Yoonsuck


    Reverse engineering of genetic regulatory networks from experimental data is the first step toward the modeling of genetic networks. Linear state-space models, also known as linear dynamical models, have been applied to model genetic networks from gene expression time series data, but existing works have not taken into account available structural information. Without structural constraints, estimated models may contradict biological knowledge and estimation methods may over-fit. In this report, we extended expectation-maximization (EM) algorithms to incorporate prior network structure and to estimate genetic regulatory networks that can track and predict gene expression profiles. We applied our method to synthetic data and to SOS data and showed that our method significantly outperforms the regular EM without structural constraints. The Matlab code is available upon request and the SOS data can be downloaded from, courtesy of Uri Alon. Zak's data is available from his website,


    negative exponentially distributed time. This system is analyzed by considering the bivariate Markov process formed by the queue-length and the number of residual service phases of the customer at the counter. (Author)

  10. Analysis of computer networks

    CERN Document Server

    Gebali, Fayez


    This textbook presents the mathematical theory and techniques necessary for analyzing and modeling high-performance global networks, such as the Internet. The three main building blocks of high-performance networks are links, switching equipment connecting the links together, and software employed at the end nodes and intermediate switches. This book provides the basic techniques for modeling and analyzing these last two components. Topics covered include, but are not limited to: Markov chains and queuing analysis, traffic modeling, interconnection networks and switch architectures and buffering strategies.   ·         Provides techniques for modeling and analysis of network software and switching equipment; ·         Discusses design options used to build efficient switching equipment; ·         Includes many worked examples of the application of discrete-time Markov chains to communication systems; ·         Covers the mathematical theory and techniques necessary for ana...


    Energy Technology Data Exchange (ETDEWEB)

    Hagen Schempf


    Automatika, Inc. was contracted by the Department of Energy (DOE) and with co-funding from the New York Gas Group (NYGAS), to develop an in-pipe natural gas prototype measurement and wireless communications system for assessing and monitoring distribution networks. In Phase II of this three-phase program, an improved prototype system was built for low-pressure cast-iron and high-pressure steel (including a no-blow installation system) mains and tested in a serial-network configuration in a live network in Long Island with the support of Keyspan Energy, Inc. The experiment was carried out in several open-hole excavations over a multi-day period. The prototype units (3 total) combined sensors capable of monitoring pressure, flow, humidity, temperature and vibration, which were sampled and combined in data-packages in an in-pipe master-repeater-slave configuration in serial or ladder-network arrangements. It was verified that the system was capable of performing all data-sampling, data-storage and collection as expected, yielding interesting results as to flow-dynamics and vibration-detection. Wireless in-pipe communications were shown to be feasible and the system was demonstrated to run off in-ground battery- and above-ground solar power. The remote datalogger access and storage-card features were demonstrated and used to log and post-process system data. Real-time data-display on an updated Phase-I GUI was used for in-field demonstration and troubleshooting.

  12. System markets: Indirect network effects in action, or inaction?

    NARCIS (Netherlands)

    J.L.G. Binken (Jeroen)


    textabstractIn this dissertation, I empirically examine system markets up close. More specifically I examine indirect network effects, both demand-side and supply-side indirect network effects. Indirect network effects are the source of positive feedback in system markets, or so network effect

  13. Aviation security cargo inspection queuing simulation model for material flow and accountability (United States)

    Allgood, Glenn O.; Olama, Mohammed M.; Rose, Terri A.; Brumback, Daryl


    Beginning in 2010, the U.S. will require that all cargo loaded in passenger aircraft be inspected. This will require more efficient processing of cargo and will have a significant impact on the inspection protocols and business practices of government agencies and the airlines. In this paper, we develop an aviation security cargo inspection queuing simulation model for material flow and accountability that will allow cargo managers to conduct impact studies of current and proposed business practices as they relate to inspection procedures, material flow, and accountability.

  14. 23 CFR 661.43 - Can other sources of funds be used to finance a queued project in advance of receipt of IRRBP funds? (United States)


    ... 23 Highways 1 2010-04-01 2010-04-01 false Can other sources of funds be used to finance a queued project in advance of receipt of IRRBP funds? 661.43 Section 661.43 Highways FEDERAL HIGHWAY... PROGRAM § 661.43 Can other sources of funds be used to finance a queued project in advance of receipt of...

  15. System/360 Computer Assisted Network Scheduling (CANS) System (United States)

    Brewer, A. C.


    Computer assisted scheduling techniques that produce conflict-free and efficient schedules have been developed and implemented to meet needs of the Manned Space Flight Network. CANS system provides effective management of resources in complex scheduling environment. System is automated resource scheduling, controlling, planning, information storage and retrieval tool.

  16. Analysis and design of networked control systems

    CERN Document Server

    You, Keyou; Xie, Lihua


    This monograph focuses on characterizing the stability and performance consequences of inserting limited-capacity communication networks within a control loop. The text shows how integration of the ideas of control and estimation with those of communication and information theory can be used to provide important insights concerning several fundamental problems such as: ·         minimum data rate for stabilization of linear systems over noisy channels; ·         minimum network requirement for stabilization of linear systems over fading channels; and ·         stability of Kalman filtering with intermittent observations. A fundamental link is revealed between the topological entropy of linear dynamical systems and the capacities of communication channels. The design of a logarithmic quantizer for the stabilization of linear systems under various network environments is also extensively discussed and solutions to many problems of Kalman filtering with intermittent observations are de...

  17. Conceptualizing and Advancing Research Networking Systems. (United States)

    Schleyer, Titus; Butler, Brian S; Song, Mei; Spallek, Heiko


    Science in general, and biomedical research in particular, is becoming more collaborative. As a result, collaboration with the right individuals, teams, and institutions is increasingly crucial for scientific progress. We propose Research Networking Systems (RNS) as a new type of system designed to help scientists identify and choose collaborators, and suggest a corresponding research agenda. The research agenda covers four areas: foundations, presentation, architecture, and evaluation. Foundations includes project-, institution- and discipline-specific motivational factors; the role of social networks; and impression formation based on information beyond expertise and interests. Presentation addresses representing expertise in a comprehensive and up-to-date manner; the role of controlled vocabularies and folksonomies; the tension between seekers' need for comprehensive information and potential collaborators' desire to control how they are seen by others; and the need to support serendipitous discovery of collaborative opportunities. Architecture considers aggregation and synthesis of information from multiple sources, social system interoperability, and integration with the user's primary work context. Lastly, evaluation focuses on assessment of collaboration decisions, measurement of user-specific costs and benefits, and how the large-scale impact of RNS could be evaluated with longitudinal and naturalistic methods. We hope that this article stimulates the human-computer interaction, computer-supported cooperative work, and related communities to pursue a broad and comprehensive agenda for developing research networking systems.

  18. Conceptualizing and Advancing Research Networking Systems (United States)



    Science in general, and biomedical research in particular, is becoming more collaborative. As a result, collaboration with the right individuals, teams, and institutions is increasingly crucial for scientific progress. We propose Research Networking Systems (RNS) as a new type of system designed to help scientists identify and choose collaborators, and suggest a corresponding research agenda. The research agenda covers four areas: foundations, presentation, architecture, and evaluation. Foundations includes project-, institution- and discipline-specific motivational factors; the role of social networks; and impression formation based on information beyond expertise and interests. Presentation addresses representing expertise in a comprehensive and up-to-date manner; the role of controlled vocabularies and folksonomies; the tension between seekers’ need for comprehensive information and potential collaborators’ desire to control how they are seen by others; and the need to support serendipitous discovery of collaborative opportunities. Architecture considers aggregation and synthesis of information from multiple sources, social system interoperability, and integration with the user’s primary work context. Lastly, evaluation focuses on assessment of collaboration decisions, measurement of user-specific costs and benefits, and how the large-scale impact of RNS could be evaluated with longitudinal and naturalistic methods. We hope that this article stimulates the human-computer interaction, computer-supported cooperative work, and related communities to pursue a broad and comprehensive agenda for developing research networking systems. PMID:24376309

  19. Spectrally Queued Feature Selection for Robotic Visual Odometery (United States)


    recognition and decision algorithms and they have been exploring perception capabilities of numerous animals and insects . This paper describes a 3 yet to be fully exploited for robotic navigation (e.g. olfaction, pheromones , etc.) The mantis shrimp is considered to have the most

  20. Systems biology of plant molecular networks: from networks to models

    NARCIS (Netherlands)

    Valentim, F.L.


    Developmental processes are controlled by regulatory networks (GRNs), which are tightly coordinated networks of transcription factors (TFs) that activate and repress gene expression within a spatial and temporal context. In Arabidopsis thaliana, the key components and network structures of the GRNs

  1. Pathways, Networks and Systems Medicine Conferences

    Energy Technology Data Exchange (ETDEWEB)

    Nadeau, Joseph H. [Pacific Northwest Research Institute


    The 6th Pathways, Networks and Systems Medicine Conference was held at the Minoa Palace Conference Center, Chania, Crete, Greece (16-21 June 2008). The Organizing Committee was composed of Joe Nadeau (CWRU, Cleveland), Rudi Balling (German Research Centre, Brauschweig), David Galas (Institute for Systems Biology, Seattle), Lee Hood (Institute for Systems Biology, Seattle), Diane Isonaka (Seattle), Fotis Kafatos (Imperial College, London), John Lambris (Univ. Pennsylvania, Philadelphia),Harris Lewin (Univ. of Indiana, Urbana-Champaign), Edison Liu (Genome Institute of Singapore, Singapore), and Shankar Subramaniam (Univ. California, San Diego). A total of 101 individuals from 21 countries participated in the conference: USA (48), Canada (5), France (5), Austria (4), Germany (3), Italy (3), UK (3), Greece (2), New Zealand (2), Singapore (2), Argentina (1), Australia (1), Cuba (1), Denmark (1), Japan (1), Mexico (1), Netherlands (1), Spain (1), Sweden (1), Switzerland (1). With respect to speakers, 29 were established faculty members and 13 were graduate students or postdoctoral fellows. With respect to gender representation, among speakers, 13 were female and 28 were male, and among all participants 43 were female and 58 were male. Program these included the following topics: Cancer Pathways and Networks (Day 1), Metabolic Disease Networks (Day 2), Day 3 ? Organs, Pathways and Stem Cells (Day 3), and Day 4 ? Inflammation, Immunity, Microbes and the Environment (Day 4). Proceedings of the Conference were not published.

  2. The network management expert system prototype for Sun Workstations (United States)

    Leigh, Albert


    Networking has become one of the fastest growing areas in the computer industry. The emergence of distributed workstations make networking more popular because they need to have connectivity between themselves as well as with other computer systems to share information and system resources. Making the networks more efficient and expandable by selecting network services and devices that fit to one's need is vital to achieve reliability and fast throughput. Networks are dynamically changing and growing at a rate that outpaces the available human resources. Therefore, there is a need to multiply the expertise rapidly rather than employing more network managers. In addition, setting up and maintaining networks by following the manuals can be tedious and cumbersome even for an experienced network manager. This prototype expert system was developed to experiment on Sun Workstations to assist system and network managers in selecting and configurating network services.

  3. Network resource control for grid workflow management systems

    NARCIS (Netherlands)

    Strijkers, R.J.; Cristea, M.; Korkhov, V.; Marchal, D.; Belloum, A.; Laat,; Meijer, R.J.


    Grid workflow management systems automate the orchestration of scientific applications with large computational and data processing needs, but lack control over network resources. Consequently, the management system cannot prevent multiple communication intensive applications to compete for network

  4. Computer-communication networks

    CERN Document Server

    Meditch, James S


    Computer- Communication Networks presents a collection of articles the focus of which is on the field of modeling, analysis, design, and performance optimization. It discusses the problem of modeling the performance of local area networks under file transfer. It addresses the design of multi-hop, mobile-user radio networks. Some of the topics covered in the book are the distributed packet switching queuing network design, some investigations on communication switching techniques in computer networks and the minimum hop flow assignment and routing subject to an average message delay constraint

  5. Comparing an Approximate Queuing Approach with Simulation for the Solution of a Cross-Docking Problem

    Directory of Open Access Journals (Sweden)

    Roberta Briesemeister


    Full Text Available Cross-docking is a logistics management concept in which products are temporarily unloaded at intermediate facilities and loaded onto output trucks to be sent to their final destination. In this paper, we propose an approximate nonstationary queuing model to size the number of docks to receive the trucks, so that their unloading will be as short as possible at the receiving dock, thus making the cross-docking process more efficient. It is observed that the stochastic queuing process may not reach the steady equilibrium state. A type of modeling that does not depend on the stationary characteristics of the process developed is applied. In order to measure the efficiency, performance, and possible adjustments of the parameters of the algorithm, an alternative simulation model is proposed using the Arena® software. The simulation uses analytic tools to make the problem more detailed, which is not allowed in the theoretical model. The computational analysis compares the results of the simulated model with the ones obtained with the theoretical algorithm, considering the queue length and the average waiting time of the trucks. Based on the results obtained, the simulation represented very well the proposed problem and possible changes can be easily detected with small adjustments in the simulated model.

  6. Optical fiber telecommunications systems and networks

    CERN Document Server

    Kaminow, Ivan; Willner, Alan E


    Optical Fiber Telecommunications VI (A&B) is the sixth in a series that has chronicled the progress in the R&D of lightwave communications since the early 1970s. Written by active authorities from academia and industry, this edition brings a fresh look to many essential topics, including devices, subsystems, systems and networks. A central theme is the enabling of high-bandwidth communications in a cost-effective manner for the development of customer applications. These volumes are an ideal reference for R&D engineers and managers, optical systems implementers, university researchers and s


    Directory of Open Access Journals (Sweden)

    G. Rajesh


    Full Text Available Sudden Infant Death Syndrome (SIDS is marked by the sudden death of an infant during sleep that is not predicted by the medical history and remains unexplained even after thorough forensic autopsy and detailed death investigation. In this we developed a system that provides solutions for the above problems by making the crib smart using the wireless sensor networks (WSN and smart phones. The system provides visual monitoring service through live video, alert services by crib fencing and awakens alert, monitoring services by temperature reading and light intensity reading, vaccine reminder and weight monitoring.

  8. Future Wireless Networks and Information Systems Volume 1

    CERN Document Server


    This volume contains revised and extended research articles written by prominent researchers participating in ICFWI 2011 conference. The 2011 International Conference on Future Wireless Networks and Information Systems (ICFWI 2011) has been held on November 30 ~ December 1, 2011, Macao, China. Topics covered include Wireless Information Networks, Wireless Networking Technologies, Mobile Software and Services, intelligent computing, network management, power engineering, control engineering, Signal and Image Processing, Machine Learning, Control Systems and Applications, The book will offer the states of arts of tremendous advances in Wireless Networks and Information Systems and also serve as an excellent reference work for researchers and graduate students working on Wireless Networks and Information Systems.

  9. Queuing theory models used for port equipment sizing (United States)

    Dragu, V.; Dinu, O.; Ruscă, A.; Burciu, Ş.; Roman, E. A.


    The significant growth of volumes and distances on road transportation led to the necessity of finding solutions to increase water transportation market share together with the handling and transfer technologies within its terminals. It is widely known that the biggest times are consumed within the transport terminals (loading/unloading/transfer) and so the necessity of constantly developing handling techniques and technologies in concordance with the goods flows size so that the total waiting time of ships within ports is reduced. Port development should be achieved by harmonizing the contradictory interests of port administration and users. Port administrators aim profit increase opposite to users that want savings by increasing consumers’ surplus. The difficulty consists in the fact that the transport demand - supply equilibrium must be realised at costs and goods quantities transiting the port in order to satisfy the interests of both parties involved. This paper presents a port equipment sizing model by using queueing theory so that the sum of costs for ships waiting operations and equipment usage would be minimum. Ship operation within the port is assimilated to a mass service waiting system in which parameters are later used to determine the main costs for ships and port equipment.

  10. Network video transmission system based on SOPC (United States)

    Zhang, Zhengbing; Deng, Huiping; Xia, Zhenhua


    Video systems have been widely used in many fields such as conferences, public security, military affairs and medical treatment. With the rapid development of FPGA, SOPC has been paid great attentions in the area of image and video processing in recent years. A network video transmission system based on SOPC is proposed in this paper for the purpose of video acquisition, video encoding and network transmission. The hardware platform utilized to design the system is an SOPC board of model Altera's DE2, which includes an FPGA chip of model EP2C35F672C6, an Ethernet controller and a video I/O interface. An IP core, known as Nios II embedded processor, is used as the CPU of the system. In addition, a hardware module for format conversion of video data, and another module to realize Motion-JPEG have been designed with Verilog HDL. These two modules are attached to the Nios II processor as peripheral equipments through the Avalon bus. Simulation results show that these two modules work as expected. Uclinux including TCP/IP protocol as well as the driver of Ethernet controller is chosen as the embedded operating system and an application program scheme is proposed.

  11. Virtualized Network Function Orchestration System and Experimental Network Based QR Recognition for a 5G Mobile Access Network

    Directory of Open Access Journals (Sweden)

    Misun Ahn


    Full Text Available This paper proposes a virtualized network function orchestration system based on Network Function Virtualization (NFV, one of the main technologies in 5G mobile networks. This system should provide connectivity between network devices and be able to create flexible network function and distribution. This system focuses more on access networks. By experimenting with various scenarios of user service established and activated in a network, we examine whether rapid adoption of new service is possible and whether network resources can be managed efficiently. The proposed method is based on Bluetooth transfer technology and mesh networking to provide automatic connections between network machines and on a Docker flat form, which is a container virtualization technology for setting and managing key functions. Additionally, the system includes a clustering and recovery measure regarding network function based on the Docker platform. We will briefly introduce the QR code perceived service as a user service to examine the proposal and based on this given service, we evaluate the function of the proposal and present analysis. Through the proposed approach, container relocation has been implemented according to a network device’s CPU usage and we confirm successful service through function evaluation on a real test bed. We estimate QR code recognition speed as the amount of network equipment is gradually increased, improving user service and confirm that the speed of recognition is increased as the assigned number of network devices is increased by the user service.

  12. Decentralized control of transmission rates in energy-critical wireless networks

    KAUST Repository

    Xia, Li


    In this paper, we discuss the decentralized optimization of delay and energy consumption in a multi-hop wireless network. The goal is to minimize the energy consumption of energy-critical nodes and the overall packet transmission delay of the network. The transmission rates of energy-critical nodes are adjustable according to the local information of nodes, i.e., the length of packets queued. The multi-hop network is modeled as a queueing network.We prove that the system performance is monotone w.r.t. (with respect to) the transmission rate, thus the “bang-bang” control is an optimal control. We also prove that there exists a threshold type control policy which is optimal. We propose a decentralized algorithm to control transmission rates of these energy-critical nodes. Some simulation experiments are conducted to demonstrate the effectiveness of our approach.

  13. Intrusion Detection in Networked Control Systems: From System Knowledge to Network Security

    NARCIS (Netherlands)

    Caselli, M.


    Networked control system‿ (NCS) is an umbrella term encompassing a broad variety of infrastructures such as industrial control systems (ICSs) and building automation systems (BASs). Nowadays, all these infrastructures play an important role in several aspects of our daily life, from managing


    Directory of Open Access Journals (Sweden)



    Full Text Available In this paper we checked the principal researches and theories to explain the attention system functioning.We are going to start reviewing along time about the concept of attention, from filter theories andresources distributor theories, to the current theories in which attention is conceived as a control system.From this last point of view, we will emphasize on the attentional networks theory of Posner, thatproposes different systems to explain diverse aspects of attention, but they are related to each other. Atlast in this paper, we will mention experimental results that have been important to characterize theselective attentional mechanisms of the human visual system, using the attentional spotlight model forthis aim.

  15. An Optimal Medium Access Control with Partial Observations for Sensor Networks

    Directory of Open Access Journals (Sweden)

    Servetto Sergio D


    Full Text Available We consider medium access control (MAC in multihop sensor networks, where only partial information about the shared medium is available to the transmitter. We model our setting as a queuing problem in which the service rate of a queue is a function of a partially observed Markov chain representing the available bandwidth, and in which the arrivals are controlled based on the partial observations so as to keep the system in a desirable mildly unstable regime. The optimal controller for this problem satisfies a separation property: we first compute a probability measure on the state space of the chain, namely the information state, then use this measure as the new state on which the control decisions are based. We give a formal description of the system considered and of its dynamics, we formalize and solve an optimal control problem, and we show numerical simulations to illustrate with concrete examples properties of the optimal control law. We show how the ergodic behavior of our queuing model is characterized by an invariant measure over all possible information states, and we construct that measure. Our results can be specifically applied for designing efficient and stable algorithms for medium access control in multiple-accessed systems, in particular for sensor networks.

  16. The Simulation and Study of the Operating System Efficiency Improvement of a Container Terminal

    Directory of Open Access Journals (Sweden)

    Liang Di


    Full Text Available With the rapid expansion of Chinese container terminal throughput, each container terminal increasingly pays attention to the operational efficiency of storage yard. In this paper, aim at the problem of excessive containers relocation assignments to establish the slotting optimization allocation model, and verify the validity of the model by using Matlab; Using tandem queuing network modeling to build model of the container terminal operating system,and simulate the container terminal logistics system by Witness. It can provide a reference for efficiency improvement of the container terminal operating system.

  17. Implementing ETC System on Hungarian Motorway Network

    Directory of Open Access Journals (Sweden)

    Katalin Tanczos


    Full Text Available Question of transport infrastructure charges - among others- covers calculation and allocation of infrastructure costsreferring different users. Cost allocation forms the basis of settingthe user charges. The reason for the existence of applyingmileage-proportional pricing system is generally accepted, asthe European regulations also discuss this topic seriously. Thismileage-proportional pricing system demands an appropriatetoll collecting system, which meets the requirements of arrangedprinciples. Among these, the most important principlesare equity, effectiveness and efficiency. Electronic Toll Collecting(ETC systems are an appropriate solution to solvingcharging problems in various ways according to the differentkind of systems. In Hungary the current motorway charging systemis not an adequate solution for success of these principlesin the long-term. A new, mileage-proportional pricing system isbeing initiated. This study presents the plans of HungarianETC system for motorway network, focusing on introductoryissues. Among several preparatory steps, examining acceptabilitybarriers of ETC system for the stakeholders of transport isneeded. Their problem perception is to satisfy their- often contrary-demands in equal, fair and effective ways. The policy implementationprocess also plays an important role to generatesufficient conditions to implement this solution. This contributionis to discuss these objectives in applying the ETC system inan acceptable way.

  18. Network Traffic Features for Anomaly Detection in Specific Industrial Control System Network

    Directory of Open Access Journals (Sweden)

    Matti Mantere


    Full Text Available The deterministic and restricted nature of industrial control system networks sets them apart from more open networks, such as local area networks in office environments. This improves the usability of network security, monitoring approaches that would be less feasible in more open environments. One of such approaches is machine learning based anomaly detection. Without proper customization for the special requirements of the industrial control system network environment, many existing anomaly or misuse detection systems will perform sub-optimally. A machine learning based approach could reduce the amount of manual customization required for different industrial control system networks. In this paper we analyze a possible set of features to be used in a machine learning based anomaly detection system in the real world industrial control system network environment under investigation. The network under investigation is represented by architectural drawing and results derived from network trace analysis. The network trace is captured from a live running industrial process control network and includes both control data and the data flowing between the control network and the office network. We limit the investigation to the IP traffic in the traces.

  19. Evaluation of a Cyber Security System for Hospital Network. (United States)

    Faysel, Mohammad A


    Most of the cyber security systems use simulated data in evaluating their detection capabilities. The proposed cyber security system utilizes real hospital network connections. It uses a probabilistic data mining algorithm to detect anomalous events and takes appropriate response in real-time. On an evaluation using real-world hospital network data consisting of incoming network connections collected for a 24-hour period, the proposed system detected 15 unusual connections which were undetected by a commercial intrusion prevention system for the same network connections. Evaluation of the proposed system shows a potential to secure protected patient health information on a hospital network.

  20. Virtual Social Networks Online and Mobile Systems

    Directory of Open Access Journals (Sweden)

    Maytham Safar


    Full Text Available Location-based applications are one of the most anticipated new segments of the mobile industry. These new applications are enabled by GPS-equipped phones (e.g., emergency applications, buddy finders, games, location-based advertising, etc.. These services are designed to give consumers instant access to personalized, local content of their immediate location. Some applications couple LBS with notification services, automatically alerting users when they are close to a pre-selected destination. With the advances in the Internet and communications/mobile technology, it became vital to analyze the effect of such technologies on human communications. This work studies how humans can construct social networks as a method for group communications using the available technologies. We constructed and analyzed a friends network using different parameters. The parameters that were calculated to analyze the network are the distribution sequence, characteristic path length, clustering coefficient and centrality measures. In addition, we built a PDA application that implements the concept of LBS using two system modules. In the first module, we have developed an application for entertainment purpose; an application program which enables end users to send their birth year and get their horoscope in return. The second part of the project was, to build an application, which helps people to stay in touch with their friends and family members (Find Friend. It helps users to find which of their buddies are within the same area they are in.

  1. Advanced systems engineering and network planning support (United States)

    Walters, David H.; Barrett, Larry K.; Boyd, Ronald; Bazaj, Suresh; Mitchell, Lionel; Brosi, Fred


    The objective of this task was to take a fresh look at the NASA Space Network Control (SNC) element for the Advanced Tracking and Data Relay Satellite System (ATDRSS) such that it can be made more efficient and responsive to the user by introducing new concepts and technologies appropriate for the 1997 timeframe. In particular, it was desired to investigate the technologies and concepts employed in similar systems that may be applicable to the SNC. The recommendations resulting from this study include resource partitioning, on-line access to subsets of the SN schedule, fluid scheduling, increased use of demand access on the MA service, automating Inter-System Control functions using monitor by exception, increase automation for distributed data management and distributed work management, viewing SN operational control in terms of the OSI Management framework, and the introduction of automated interface management.

  2. Approximate Dynamic Programming techniques for the control of time-varying queueing systems applied to call centers with abandonments and retrials

    NARCIS (Netherlands)

    Roubos, D.; Bhulai, S.


    In this article we develop techniques for applying Approximate Dynamic Programming (ADP) to the control of time-varying queuing systems. First, we show that the classical state space representation in queuing systems leads to approximations that can be significantly improved by increasing the

  3. Control and Optimization of Network in Networked Control System

    Directory of Open Access Journals (Sweden)

    Wang Zhiwen


    Full Text Available In order to avoid quality of performance (QoP degradation resulting from quality of service (QoS, the solution to network congestion from the point of control theory, which marks departure of our results from the existing methods, is proposed in this paper. The congestion and bandwidth are regarded as state and control variables, respectively; then, the linear time-invariant (LTI model between congestion state and bandwidth of network is established. Consequently, linear quadratic method is used to eliminate the network congestion by allocating bandwidth dynamically. At last, numerical simulation results are given to illustrate the effectiveness of this modeling approach.

  4. Handbook of sensor networks compact wireless and wired sensing systems

    CERN Document Server

    Ilyas, Mohammad


    INTRODUCTION Opportunities and Challenges in Wireless Sensor Networks, M. Haenggi, Next Generation Technologies to Enable Sensor Networks, J. I.  Goodman, A. I. Reuther, and D. R. Martinez Sensor Networks Management, L. B. Ruiz, J. M. Nogueira, and A. A. F. Loureiro Models for Programmability in Sensor Networks, A. Boulis Miniaturizing Sensor Networks with MEMS, Brett Warneke A Taxonomy of Routing Techniques in Wireless Sensor Networks, J. N. Al-Karaki and A. E. Kamal Artificial Perceptual Systems, A. Loutfi, M. Lindquist, and P. Wide APPLICATIONS Sensor Network Architecture and Appl


    Directory of Open Access Journals (Sweden)

    Vivek Kumar Yadav


    Full Text Available Network security checking is a vital process to assess and to identify weaknesses in network for management of security. Insecure entry points of a network provide attackers an easy target to access and compromise. Open ports of network components such as firewalls, gateways and end systems are analogues to open gates of a building through which any one can get into. Network scanning is performed to identify insecure entry points in the network components. To find out vulnerabilities on these points vulnerability assessment is performed. So security checking consists of both activities- network scanning as well as vulnerability assessment. A single tool used for the security checking may not give reliable results. This paper presents a framework for assessing the security of a network using multiple Network Scanning and Vulnerability Assessment tools. The proposed framework is an extension of the framework given by Jun Yoon and Wontae Sim [1] which performs vulnerability scanning only. The framework presented here adds network scanning, alerting and reporting system to their framework. Network scanning and vulnerability tools together complement each other and make it amenable for centralized control and management. The reporting system of framework sends an email to the network administrator which contains detailed report (as attachment of security checking process. Alerting system sends a SMS message as an alert to the network administrator in case of severe threats found in the network. Initial results of the framework are encouraging and further work is in progress.

  6. Introducing network Gramians to undirected network systems for structure-preserving model reduction

    NARCIS (Netherlands)

    Cheng, Xiaodong; Scherpen, Jacquelien M.A.


    In this paper, we propose the notion of controllability Gramian for linear network systems. In contrast to the conventional Gramians defined for asymptotically stable systems, the new Gramian is generalized to semi-stable systems and can be computed for network systems with imaginary axis poles. We

  7. Advances in dynamic network modeling in complex transportation systems

    CERN Document Server

    Ukkusuri, Satish V


    This book focuses on the latest in dynamic network modeling, including route guidance and traffic control in transportation systems and other complex infrastructure networks. Covers dynamic traffic assignment, flow modeling, mobile sensor deployment and more.

  8. A network-based dynamical ranking system for competitive sports

    National Research Council Canada - National Science Library

    Motegi, Shun; Masuda, Naoki


    From the viewpoint of networks, a ranking system for players or teams in sports is equivalent to a centrality measure for sports networks, whereby a directed link represents the result of a single game...

  9. Deep Space Network information system architecture study (United States)

    Beswick, C. A.; Markley, R. W. (Editor); Atkinson, D. J.; Cooper, L. P.; Tausworthe, R. C.; Masline, R. C.; Jenkins, J. S.; Crowe, R. A.; Thomas, J. L.; Stoloff, M. J.


    The purpose of this article is to describe an architecture for the DSN information system in the years 2000-2010 and to provide guidelines for its evolution during the 1990's. The study scope is defined to be from the front-end areas at the antennas to the end users (spacecraft teams, principal investigators, archival storage systems, and non-NASA partners). The architectural vision provides guidance for major DSN implementation efforts during the next decade. A strong motivation for the study is an expected dramatic improvement in information-systems technologies--i.e., computer processing, automation technology (including knowledge-based systems), networking and data transport, software and hardware engineering, and human-interface technology. The proposed Ground Information System has the following major features: unified architecture from the front-end area to the end user; open-systems standards to achieve interoperability; DSN production of level 0 data; delivery of level 0 data from the Deep Space Communications Complex, if desired; dedicated telemetry processors for each receiver; security against unauthorized access and errors; and highly automated monitor and control.

  10. Optimal Allocation of Changing Station for Electric Vehicle Based on Queuing Theory

    Directory of Open Access Journals (Sweden)

    Yagang Zhang


    Full Text Available Electric vehicle as the main development direction of the future automotive industry, has gained attention worldwide. The rationality of the planning and construction of the power station, as the foundation of energy supply, is an important premise for the development of electric vehicles. In full consideration of the electric demand and electricity consumption, this paper proposes a new construction mode in which charging station and centralized charging station are appropriately combined and presents a location optimization model. Not only can this model be applied to determine the appropriate location for the power station, but it can use the queuing theory to determine the optimal number of power equipment, with which we can achieve the minimum costs. Finally, taking a certain city as an example, the optimum plan for power station is calculated by using this model, which provides an important reference for the study of electric vehicle infrastructure planning.

  11. An artificial immune system algorithm approach for reconfiguring distribution network (United States)

    Syahputra, Ramadoni; Soesanti, Indah


    This paper proposes an artificial immune system (AIS) algorithm approach for reconfiguring distribution network with the presence distributed generators (DG). The distribution network with high-performance is a network that has a low power loss, better voltage profile, and loading balance among feeders. The task for improving the performance of the distribution network is optimization of network configuration. The optimization has become a necessary study with the presence of DG in entire networks. In this work, optimization of network configuration is based on an AIS algorithm. The methodology has been tested in a model of 33 bus IEEE radial distribution networks with and without DG integration. The results have been showed that the optimal configuration of the distribution network is able to reduce power loss and to improve the voltage profile of the distribution network significantly.

  12. Geometric universality of currents in an open network of interacting particles

    Energy Technology Data Exchange (ETDEWEB)

    Sinitsyn, Nikolai A [Los Alamos National Laboratory; Chernyak, Vladimir Y [Los Alamos National Laboratory; Chertkov, Michael [Los Alamos National Laboratory


    We discuss a non-equilibrium statistical system on a graph or network. Identical particles are injected, interact with each other, traverse, and leave the graph in a stochastic manner described in terms of Poisson rates, possibly dependent on time and instantaneous occupation numbers at the nodes of the graph. We show that under the assumption of the relative rates constancy, the system demonstrates a profound statistical symmetry, resulting in geometric universality of the particle currents statistics. The phenomenon applies broadly to many man-made and natural open stochastic systems, such as queuing of packages over internet, transport of electrons and quasi-particles in mesoscopic systems, and chains of reactions in bio-chemical networks. We illustrate the utility of the general approach using two enabling examples from the two latter disciplines.

  13. Network versus portfolio structure in financial systems (United States)

    Kobayashi, Teruyoshi


    The question of how to stabilize financial systems has attracted considerable attention since the global financial crisis of 2007-2009. Recently, Beale et al. [Proc. Natl. Acad. Sci. USA 108, 12647 (2011)] demonstrated that higher portfolio diversity among banks would reduce systemic risk by decreasing the risk of simultaneous defaults at the expense of a higher likelihood of individual defaults. In practice, however, a bank default has an externality in that it undermines other banks’ balance sheets. This paper explores how each of these different sources of risk, simultaneity risk and externality, contributes to systemic risk. The results show that the allocation of external assets that minimizes systemic risk varies with the topology of the financial network as long as asset returns have negative correlations. In the model, a well-known centrality measure, PageRank, reflects an appropriately defined “infectiveness” of a bank. An important result is that the most infective bank needs not always to be the safest bank. Under certain circumstances, the most infective node should act as a firewall to prevent large-scale collective defaults. The introduction of a counteractive portfolio structure will significantly reduce systemic risk.

  14. Artificial Neural Network System for Thyroid Diagnosis

    Directory of Open Access Journals (Sweden)

    Mazin Abdulrasool Hameed


    Full Text Available Thyroid disease is one of major causes of severe medical problems for human beings. Therefore, proper diagnosis of thyroid disease is considered as an important issue to determine treatment for patients. This paper focuses on using Artificial Neural Network (ANN as a significant technique of artificial intelligence to diagnose thyroid diseases. The continuous values of three laboratory blood tests are used as input signals to the proposed system of ANN. All types of thyroid diseases that may occur in patients are taken into account in design of system, as well as the high accuracy of the detection and categorization of thyroid diseases are considered in the system. A multilayer feedforward architecture of ANN is adopted in the proposed design, and the back propagation is selected as learning algorithm to accomplish the training process. The result of this research shows that the proposed ANN system is able to precisely diagnose thyroid disease, and can be exploited in practical uses. The system is simulated via MATLAB software to evaluate its performance

  15. Neural network system for traffic flow management (United States)

    Gilmore, John F.; Elibiary, Khalid J.; Petersson, L. E. Rickard


    Atlanta will be the home of several special events during the next five years ranging from the 1996 Olympics to the 1994 Super Bowl. When combined with the existing special events (Braves, Falcons, and Hawks games, concerts, festivals, etc.), the need to effectively manage traffic flow from surface streets to interstate highways is apparent. This paper describes a system for traffic event response and management for intelligent navigation utilizing signals (TERMINUS) developed at Georgia Tech for adaptively managing special event traffic flows in the Atlanta, Georgia area. TERMINUS (the original name given Atlanta, Georgia based upon its role as a rail line terminating center) is an intelligent surface street signal control system designed to manage traffic flow in Metro Atlanta. The system consists of three components. The first is a traffic simulation of the downtown Atlanta area around Fulton County Stadium that models the flow of traffic when a stadium event lets out. Parameters for the surrounding area include modeling for events during various times of day (such as rush hour). The second component is a computer graphics interface with the simulation that shows the traffic flows achieved based upon intelligent control system execution. The final component is the intelligent control system that manages surface street light signals based upon feedback from control sensors that dynamically adapt the intelligent controller's decision making process. The intelligent controller is a neural network model that allows TERMINUS to control the configuration of surface street signals to optimize the flow of traffic away from special events.

  16. Transformation of legacy network management system to service oriented architecture (United States)

    Sathyan, Jithesh; Shenoy, Krishnananda


    Service providers today are facing the challenge of operating and maintaining multiple networks, based on multiple technologies. Network Management System (NMS) solutions are being used to manage these networks. However the NMS is tightly coupled with Element or the Core network components. Hence there are multiple NMS solutions for heterogeneous networks. Current network management solutions are targeted at a variety of independent networks. The wide spread popularity of IP Multimedia Subsystem (IMS) is a clear indication that all of these independent networks will be integrated into a single IP-based infrastructure referred to as Next Generation Networks (NGN) in the near future. The services, network architectures and traffic pattern in NGN will dramatically differ from the current networks. The heterogeneity and complexity in NGN including concepts like Fixed Mobile Convergence will bring a number of challenges to network management. The high degree of complexity accompanying the network element technology necessitates network management systems (NMS) which can utilize this technology to provide more service interfaces while hiding the inherent complexity. As operators begin to add new networks and expand existing networks to support new technologies and products, the necessity of scalable, flexible and functionally rich NMS systems arises. Another important factor influencing NMS architecture is mergers and acquisitions among the key vendors. Ease of integration is a key impediment in the traditional hierarchical NMS architecture. These requirements trigger the need for an architectural framework that will address the NGNM (Next Generation Network Management) issues seamlessly. This paper presents a unique perspective of bringing service orientated architecture (SOA) to legacy network management systems (NMS). It advocates a staged approach in transforming a legacy NMS to SOA. The architecture at each stage is detailed along with the technical advantages and

  17. Queuing and convergence properties of a dynamic assignment model for congested networks

    NARCIS (Netherlands)

    Troost, J.F.; Botma, H.; Bovy, P.H.L.


    The growing congestion problems demand a new generation of traffic models that are applicable in the planning and management of infrastructure. The aim of this thesis is the development of a traffic model able to predict congestions and their influence on traffic operation. This model is meant for

  18. Numerical analysis of minimum cost network flow with queuing stations: the M/M/1 case

    Directory of Open Access Journals (Sweden)

    Salvador Hernández-González


    Full Text Available En una red los nodos representan estaciones, almacenes, centros de distribución y c lientes y circulan tanto materiales como información, por lo que una herramienta utilizada para apoyar la toma de decisiones es el modelo de flujo a costo mínimo que toma en cuenta únicamente costos de transporte. En la realidad los nodos prestan un servic io el cual requiere un tiempo de servicio, la atención sigue una disciplina y además se forma una fila de espera. En este trabajo se propone una modificación del modelo de flujo a costo mínimo para la optimización en redes de líneas de espera. Se resolvier on varios casos donde se observa un grado de exactitud aceptable en el cálculo del tiempo de ciclo y trabajo en proceso. El trabajo es de interés para los administradores y/o responsables de las cadenas de abasto y útil para la toma de dec i siones a mediano y largo plazo.

  19. Designing the optimal robotic milking barn by applying a queuing network approach

    NARCIS (Netherlands)

    Halachmi, I.; Adan, I.J.B.F.; Wald, van der J.; Beek, van P.; Heesterbeek, J.A.P.


    The design of various conventional dairy barns is based on centuries of experience, but there is hardly any experience with robotic milking barns (RMB). Furthermore, as each farmer has his own management practices, the optimal layout is `site dependent¿. A new universally applicable design

  20. Designing the optimal robotic milking barn: applying a queuing network approach

    NARCIS (Netherlands)

    Halachmi, I.; Adan, I.J.B.F.; Wal, J. van der; Beek, P. van; Heesterbeek, J.A.P.


    The design of various conventional dairy barns is based on centuries of experience, but there is hardly any experience with robotic milking barns (RMB). Furthermore, as each farmer has his own management practices, the optimal layout is 'site dependent'. A new universally applicable design

  1. Sustainable coastal sensor networks: technologies and challenges (United States)

    Carapezza, Edward M.; Butman, Jerry; Babb, Ivar; Bucklin, Ann


    This paper describes a distributed sensor network for a coastal maritime security system. This concept incorporates a network of small passive and active multi-phenomenological unattended sensors and shore based optical sensors to detect, classify, and track submerged threat objects approaching high value coastal assets, such as ports, harbors, residential, commercial, and military facilities and areas. The network of unattended, in-water sensors perform the initial detection, classification, and coarse tracking and then queues shore based optical laser radar sensors. These shore-based sensors perform a queued sector search to develop a refined track on the submerged threat objects that were initially detected by the unattended sensor network. Potential threat objects include swimmers, small unmanned underwater vehicles (UUV's), small submarines, and submerged barges. All of these threats have the potential to transport threat objects such as explosives, chemical, biological, radiological, and nuclear materials. Reliable systems with low false alarm rates (FAR) are proposed. Tens to hundreds of low cost passive sensors are proposed to be deployed conjunctively with several active acoustic and optical sensors in threat and facility dependant patterns to maximize the detection, tracking and classification of submerged threat objects. The integrated command and control system and novel microbial fuel cells to power these sensor networks are also described.

  2. An open network type DCME system (United States)

    Kato, T.; Suga, K.; Hagi, K.; Ohtsuki, H.; Shinta, M.; Kinoshita, T.; Murata, K.


    The first open network-type digital circuit multiplication equipment (DCME) system, which complies with Intelsat IESS-501 (Rev.2), Eutelsat BS14-49E, CCITT Rec. G.723, G.721, and Rec. Q.50 specifications, has been developed. It provides an economical way to multiply circuit capacity by using DSI and variable bit rate adaptive differential pulse code modulation techniques. It is flexible enough to support a variety of operation modes such as Multidestination for up to four destinations, Multiclique for up to two destinations, Single destination, and Mixed Single-destination and Multidestination operations. In addition, it offers a wide range of possibilities in satellite, submarine, and terrestrial applications. The newly-developed DCME system utilizes a modified adaptive threshold activity detector and an accurate, robust data/speech discriminator in order to prevent false detection and false decisions in high background noise environment. In the DCME system, the Operation and Maintenance Center is used to monitor the operating conditions and to control the system functions.

  3. Windows 2012 Server network security securing your Windows network systems and infrastructure

    CERN Document Server

    Rountree, Derrick


    Windows 2012 Server Network Security provides the most in-depth guide to deploying and maintaining a secure Windows network. The book drills down into all the new features of Windows 2012 and provides practical, hands-on methods for securing your Windows systems networks, including: Secure remote access Network vulnerabilities and mitigations DHCP installations configuration MAC filtering DNS server security WINS installation configuration Securing wired and wireless connections Windows personal firewall

  4. Fault Detection for Quantized Networked Control Systems

    Directory of Open Access Journals (Sweden)

    Wei-Wei Che


    Full Text Available The fault detection problem in the finite frequency domain for networked control systems with signal quantization is considered. With the logarithmic quantizer consideration, a quantized fault detection observer is designed by employing a performance index which is used to increase the fault sensitivity in finite frequency domain. The quantized measurement signals are dealt with by utilizing the sector bound method, in which the quantization error is treated as sector-bounded uncertainty. By using the Kalman-Yakubovich-Popov (GKYP Lemma, an iterative LMI-based optimization algorithm is developed for designing the quantized fault detection observer. And a numerical example is given to illustrate the effectiveness of the proposed method.

  5. Network quotients: structural skeletons of complex systems. (United States)

    Xiao, Yanghua; MacArthur, Ben D; Wang, Hui; Xiong, Momiao; Wang, Wei


    A defining feature of many large empirical networks is their intrinsic complexity. However, many networks also contain a large degree of structural repetition. An immediate question then arises: can we characterize essential network complexity while excluding structural redundancy? In this article we utilize inherent network symmetry to collapse all redundant information from a network, resulting in a coarse graining which we show to carry the essential structural information of the "parent" network. In the context of algebraic combinatorics, this coarse-graining is known as the "quotient." We systematically explore the theoretical properties of network quotients and summarize key statistics of a variety of "real-world" quotients with respect to those of their parent networks. In particular, we find that quotients can be substantially smaller than their parent networks yet typically preserve various key functional properties such as complexity (heterogeneity and hub vertices) and communication (diameter and mean geodesic distance), suggesting that quotients constitute the essential structural skeletons of their parent networks. We summarize with a discussion of potential uses of quotients in analysis of biological regulatory networks and ways in which using quotients can reduce the computational complexity of network algorithms.

  6. System Leadership, Networks and the Question of Power (United States)

    Hatcher, Richard


    The author's argument revolves around the relationships between government agendas and the agency of teachers, and between them the intermediary role of management as "system leaders" of network forms. Network is a pluralistic concept: networks can serve very different educational-political interests. They offer the potential of new…

  7. On Emulation-Based Network Intrusion Detection Systems

    NARCIS (Netherlands)

    Abbasi, Ali; Wetzel, Jos; Bokslag, Wouter; Zambon, Emmanuele; Etalle, Sandro


    Emulation-based network intrusion detection systems have been devised to detect the presence of shellcode in network traffic by trying to execute (portions of) the network packet payloads in an in- strumented environment and checking the execution traces for signs of shellcode activity.

  8. The Artifical Neural Network as means for modeling Nonlinear Systems


    Drábek Oldøich; Taufer Ivan


    The paper deals with nonlinear system identification based on neural network. The topic of this publication is simulation of training and testing a neural network. A contribution is assigned to technologists which are good at the clasical identification problems but their knowledges about identification based on neural network are only on the stage of theoretical bases.

  9. The Artifical Neural Network as means for modeling Nonlinear Systems

    Directory of Open Access Journals (Sweden)

    Drábek Oldøich


    Full Text Available The paper deals with nonlinear system identification based on neural network. The topic of this publication is simulation of training and testing a neural network. A contribution is assigned to technologists which are good at the clasical identification problems but their knowledges about identification based on neural network are only on the stage of theoretical bases.

  10. Sensitivity and network topology in chemical reaction systems (United States)

    Okada, Takashi; Mochizuki, Atsushi


    In living cells, biochemical reactions are catalyzed by specific enzymes and connect to one another by sharing substrates and products, forming complex networks. In our previous studies, we established a framework determining the responses to enzyme perturbations only from network topology, and then proved a theorem, called the law of localization, explaining response patterns in terms of network topology. In this paper, we generalize these results to reaction networks with conserved concentrations, which allows us to study any reaction system. We also propose network characteristics quantifying robustness. We compare E. coli metabolic network with randomly rewired networks, and find that the robustness of the E. coli network is significantly higher than that of the random networks.

  11. System and method for generating a relationship network (United States)

    Franks, Kasian [Kensington, CA; Myers, Cornelia A [St. Louis, MO; Podowski, Raf M [Pleasant Hill, CA


    A computer-implemented system and process for generating a relationship network is disclosed. The system provides a set of data items to be related and generates variable length data vectors to represent the relationships between the terms within each data item. The system can be used to generate a relationship network for documents, images, or any other type of file. This relationship network can then be queried to discover the relationships between terms within the set of data items.

  12. Fluctuations in Urban Traffic Networks (United States)

    Chen, Yu-Dong; Li, Li; Zhang, Yi; Hu, Jian-Ming; Jin, Xue-Xiang

    Urban traffic network is a typical complex system, in which movements of tremendous microscopic traffic participants (pedestrians, bicyclists and vehicles) form complicated spatial and temporal dynamics. We collected flow volumes data on the time-dependent activity of a typical urban traffic network, finding that the coupling between the average flux and the fluctuation on individual links obeys a certain scaling law, with a wide variety of scaling exponents between 1/2 and 1. These scaling phenomena can explain the interaction between the nodes' internal dynamics (i.e. queuing at intersections, car-following in driving) and changes in the external (network-wide) traffic demand (i.e. the every day increase of traffic amount during peak hours and shocking caused by traffic accidents), allowing us to further understand the mechanisms governing the transportation system's collective behavior. Multiscaling and hotspot features are observed in the traffic flow data as well. But the reason why the separated internal dynamics are comparable to the external dynamics in magnitude is still unclear and needs further investigations.

  13. Efficient Network Monitoring for Large Data Acquisition Systems

    CERN Document Server

    Savu, DO; The ATLAS collaboration; Al-Shabibi, A; Sjoen, R; Batraneanu, SM; Stancu, SN


    Though constantly evolving and improving, the available network monitoring solutions have limitations when applied to the infrastructure of a high speed real-time data acquisition (DAQ) system. DAQ networks are particular computer networks where experts have to pay attention to both individual subsections as well as system wide traffic flows while monitoring the network. The ATLAS Network at the Large Hadron Collider (LHC) has more than 200 switches interconnecting 3500 hosts and totaling 8500 high speed links. The use of heterogeneous tools for monitoring various infrastructure parameters, in order to assure optimal DAQ system performance, proved to be a tedious and time consuming task for experts. To alleviate this problem we used our networking and DAQ expertise to build a flexible and scalable monitoring system providing an intuitive user interface with the same look and feel irrespective of the data provider that is used. Our system uses custom developed components for critical performance monitoring and...

  14. Neural Network Based Intelligent Sootblowing System

    Energy Technology Data Exchange (ETDEWEB)

    Mark Rhode


    . Due to the composition of coal, particulate matter is also a by-product of coal combustion. Modern day utility boilers are usually fitted with electrostatic precipitators to aid in the collection of particulate matter. Although extremely efficient, these devices are sensitive to rapid changes in inlet mass concentration as well as total mass loading. Traditionally, utility boilers are equipped with devices known as sootblowers, which use, steam, water or air to dislodge and clean the surfaces within the boiler and are operated based upon established rule or operator's judgment. Poor sootblowing regimes can influence particulate mass loading to the electrostatic precipitators. The project applied a neural network intelligent sootblowing system in conjunction with state-of-the-art controls and instruments to optimize the operation of a utility boiler and systematically control boiler slagging/fouling. This optimization process targeted reduction of NOx of 30%, improved efficiency of 2% and a reduction in opacity of 5%. The neural network system proved to be a non-invasive system which can readily be adapted to virtually any utility boiler. Specific conclusions from this neural network application are listed below. These conclusions should be used in conjunction with the specific details provided in the technical discussions of this report to develop a thorough understanding of the process.

  15. A Comparison of Geographic Information Systems, Complex Networks, and Other Models for Analyzing Transportation Network Topologies (United States)

    Alexandrov, Natalia (Technical Monitor); Kuby, Michael; Tierney, Sean; Roberts, Tyler; Upchurch, Christopher


    This report reviews six classes of models that are used for studying transportation network topologies. The report is motivated by two main questions. First, what can the "new science" of complex networks (scale-free, small-world networks) contribute to our understanding of transport network structure, compared to more traditional methods? Second, how can geographic information systems (GIS) contribute to studying transport networks? The report defines terms that can be used to classify different kinds of models by their function, composition, mechanism, spatial and temporal dimensions, certainty, linearity, and resolution. Six broad classes of models for analyzing transport network topologies are then explored: GIS; static graph theory; complex networks; mathematical programming; simulation; and agent-based modeling. Each class of models is defined and classified according to the attributes introduced earlier. The paper identifies some typical types of research questions about network structure that have been addressed by each class of model in the literature.

  16. Fitness networks for real world systems via modified preferential attachment (United States)

    Shang, Ke-ke; Small, Michael; Yan, Wei-sheng


    Complex networks are virtually ubiquitous, and the Barabási and Albert model (BA model) has became an acknowledged standard for the modelling of these systems. The so-called BA model is a kind of preferential attachment growth model based on the intuitive premise that popularity is attractive. However, preferential attachment alone is insufficient to describe the diversity of complex networks observed in the real world. In this paper we first use the accuracy of a link prediction method, as a metric for network fitness. The link prediction method predicts the occurrence of links consistent with preferential attachment, the performance of this link prediction scheme is then a natural measure of the ;preferential-attachment-likeness; of a given network. We then propose several modification methods and modified BA models to construct networks which more accurately describe the fitness properties of real networks. We find that all features assortativity, degree distribution and rich-club formation can play significant roles for the network construction and eventual structure. Moreover, link sparsity and the size of a network are key factors for network reconstruction. In addition, we find that the structure of the network which is limited by geographic location (nodes are embedded in a Euclidean space and connectivity is correlated with distances) differs from other typical networks. In social networks, we observe that the high school contact network has similar structure as the friends network and so we speculate that the contact behaviours can reflect real friendships.

  17. The Network Information Management System (NIMS) in the Deep Space Network (United States)

    Wales, K. J.


    In an effort to better manage enormous amounts of administrative, engineering, and management data that is distributed worldwide, a study was conducted which identified the need for a network support system. The Network Information Management System (NIMS) will provide the Deep Space Network with the tools to provide an easily accessible source of valid information to support management activities and provide a more cost-effective method of acquiring, maintaining, and retrieval data.

  18. Complex systems and networks dynamics, controls and applications

    CERN Document Server

    Yu, Xinghuo; Chen, Guanrong; Yu, Wenwu


    This elementary book provides some state-of-the-art research results on broad disciplinary sciences on complex networks. It presents an in-depth study with detailed description of dynamics, controls and applications of complex networks. The contents of this book can be summarized as follows. First, the dynamics of complex networks, for example, the cluster dynamic analysis by using kernel spectral methods, community detection algorithms in bipartite networks, epidemiological modeling with demographics and epidemic spreading on multi-layer networks, are studied. Second, the controls of complex networks are investigated including topics like distributed finite-time cooperative control of multi-agent systems by applying homogenous-degree and Lyapunov methods, composite finite-time containment control for disturbed second-order multi-agent systems, fractional-order observer design of multi-agent systems, chaos control and anticontrol of complex systems via Parrondos game and many more. Third, the applications of ...

  19. Observing Arctic Ecology using Networked Infomechanical Systems (United States)

    Healey, N. C.; Oberbauer, S. F.; Hollister, R. D.; Tweedie, C. E.; Welker, J. M.; Gould, W. A.


    Understanding ecological dynamics is important for investigation into the potential impacts of climate change in the Arctic. Established in the early 1990's, the International Tundra Experiment (ITEX) began observational inquiry of plant phenology, plant growth, community composition, and ecosystem properties as part of a greater effort to study changes across the Arctic. Unfortunately, these observations are labor intensive and time consuming, greatly limiting their frequency and spatial coverage. We have expanded the capability of ITEX to analyze ecological phenomenon with improved spatial and temporal resolution through the use of Networked Infomechanical Systems (NIMS) as part of the Arctic Observing Network (AON) program. The systems exhibit customizable infrastructure that supports a high level of versatility in sensor arrays in combination with information technology that allows for adaptable configurations to numerous environmental observation applications. We observe stereo and static time-lapse photography, air and surface temperature, incoming and outgoing long and short wave radiation, net radiation, and hyperspectral reflectance that provides critical information to understanding how vegetation in the Arctic is responding to ambient climate conditions. These measurements are conducted concurrent with ongoing manual measurements using ITEX protocols. Our NIMS travels at a rate of three centimeters per second while suspended on steel cables that are ~1 m from the surface spanning transects ~50 m in length. The transects are located to span soil moisture gradients across a variety of land cover types including dry heath, moist acidic tussock tundra, shrub tundra, wet meadows, dry meadows, and water tracks. We have deployed NIMS at four locations on the North Slope of Alaska, USA associated with 1 km2 ARCSS vegetation study grids including Barrow, Atqasuk, Toolik Lake, and Imnavait Creek. A fifth system has been deployed in Thule, Greenland beginning in

  20. Principles of network and system administration

    CERN Document Server

    Burgess, Mark


    A practical guide for meeting the challenges of planning and designing a networkNetwork design has to be logical and efficient, decisions have to be made about what services are needed, and security concerns must be addressed. Focusing on general principles, this book will help make the process of setting up, configuring, and maintaining a network much easier. It outlines proven procedures for working in a global community of networked machines, and provides practical illustrations of technical specifics. Readers will also find broad coverage of Linux and other Unix versions, Windows(r), Macs,

  1. Efficient combined security system for wireless sensor network

    Directory of Open Access Journals (Sweden)

    N.S. Fayed


    Full Text Available Wireless Sensor Networks (WSNs need effective security mechanisms because these networks deployed in hostel unattended environments. There are many parameters affect selecting the security mechanism as its speed and energy consumption. This paper presents a combined security system for WSN that enhance the speed of the network and it is energy consumption. This system combines two strong protocols, Lightweight Kerberos and Elliptic Curve Menezes–Qu–Vanstone (ECMQV. The simulation results demonstrate that the combined system can enlarge the life time for wireless sensor networks, enhance its security, and increase its speed.

  2. Predictive Control of Networked Multiagent Systems via Cloud Computing. (United States)

    Liu, Guo-Ping


    This paper studies the design and analysis of networked multiagent predictive control systems via cloud computing. A cloud predictive control scheme for networked multiagent systems (NMASs) is proposed to achieve consensus and stability simultaneously and to compensate for network delays actively. The design of the cloud predictive controller for NMASs is detailed. The analysis of the cloud predictive control scheme gives the necessary and sufficient conditions of stability and consensus of closed-loop networked multiagent control systems. The proposed scheme is verified to characterize the dynamical behavior and control performance of NMASs through simulations. The outcome provides a foundation for the development of cooperative and coordinative control of NMASs and its applications.



    Noria Benyettou; Abdelkader Benyettou; Vincent Rodin


    With the development growing of network technology, computer networks became increasingly wide and opened. This evolution gave birth to new techniques allowing accessibility of networks and information systems with an aim of facilitating the transactions. Consequently, these techniques gave also birth to new forms of threats. In this article, we present the utility to use a system of intrusion detection through a presentation of these characteristics. Using as inspiration the i...

  4. Network analysis and Canada's large value transfer system


    Embree, Lana; Roberts, Tom


    Analysis of the characteristics and structure of a network of financial institutions can provide insight into the complex relationships and interdependencies that exist in a payment, clearing, and settlement system (PCSS), and allow an intuitive understanding of the PCSS's efficiency, stability, and resiliency. The authors review the literature related to the PCSS network and describe the daily and intraday network structure of payment activity in the Large Value Transfer System (LVTS), which...

  5. The architecture of a network level intrusion detection system

    Energy Technology Data Exchange (ETDEWEB)

    Heady, R.; Luger, G.; Maccabe, A.; Servilla, M. [New Mexico Univ., Albuquerque, NM (United States). Dept. of Computer Science


    This paper presents the preliminary architecture of a network level intrusion detection system. The proposed system will monitor base level information in network packets (source, destination, packet size, and time), learning the normal patterns and announcing anomalies as they occur. The goal of this research is to determine the applicability of current intrusion detection technology to the detection of network level intrusions. In particular, the authors are investigating the possibility of using this technology to detect and react to worm programs.

  6. Advanced information processing system: Input/output network management software (United States)

    Nagle, Gail; Alger, Linda; Kemp, Alexander


    The purpose of this document is to provide the software requirements and specifications for the Input/Output Network Management Services for the Advanced Information Processing System. This introduction and overview section is provided to briefly outline the overall architecture and software requirements of the AIPS system before discussing the details of the design requirements and specifications of the AIPS I/O Network Management software. A brief overview of the AIPS architecture followed by a more detailed description of the network architecture.

  7. Network anomaly detection system with optimized DS evidence theory. (United States)

    Liu, Yuan; Wang, Xiaofeng; Liu, Kaiyu


    Network anomaly detection has been focused on by more people with the fast development of computer network. Some researchers utilized fusion method and DS evidence theory to do network anomaly detection but with low performance, and they did not consider features of network-complicated and varied. To achieve high detection rate, we present a novel network anomaly detection system with optimized Dempster-Shafer evidence theory (ODS) and regression basic probability assignment (RBPA) function. In this model, we add weights for each sensor to optimize DS evidence theory according to its previous predict accuracy. And RBPA employs sensor's regression ability to address complex network. By four kinds of experiments, we find that our novel network anomaly detection model has a better detection rate, and RBPA as well as ODS optimization methods can improve system performance significantly.

  8. Reject mechanisms for massively parallel neural network character recognition systems (United States)

    Garris, Michael D.; Wilson, Charles L.


    Two reject mechanisms are compared using a massively parallel character recognition system implemented at NIST. The recognition system was designed to study the feasibility of automatically recognizing hand-printed text in a loosely constrained environment. The first method is a simple scalar threshold on the output activation of the winning neurode from the character classifier network. The second method uses an additional neural network trained on all outputs from the character classifier network to accept or reject assigned classifications. The neural network rejection method was expected to perform with greater accuracy than the scalar threshold method, but this was not supported by the test results presented. The scalar threshold method, even though arbitrary, is shown to be a viable reject mechanism for use with neural network character classifiers. Upon studying the performance of the neural network rejection method, analyses show that the two neural networks, the character classifier network and the rejection network, perform very similarly. This can be explained by the strong non-linear function of the character classifier network which effectively removes most of the correlation between character accuracy and all activations other than the winning activation. This suggests that any effective rejection network must receive information from the system which has not been filtered through the non-linear classifier.

  9. Review of Recommender Systems Algorithms Utilized in Social Networks based e-Learning Systems & Neutrosophic System

    Directory of Open Access Journals (Sweden)

    A. A. Salama


    Full Text Available In this paper, we present a review of different recommender system algorithms that are utilized in social networks based e-Learning systems. Future research will include our proposed our e-Learning system that utilizes Recommender System and Social Network. Since the world is full of indeterminacy, the neutrosophics found their place into contemporary research. The fundamental concepts of neutrosophic set, introduced by Smarandache in [21, 22, 23] and Salama et al. in [24-66].The purpose of this paper is to utilize a neutrosophic set to analyze social networks data conducted through learning activities.

  10. Interpreting physical flows in networks as a communication system

    Indian Academy of Sciences (India)

    communication systems and multiple-channel commu- nication systems. Moreover, we are able to interpret directly the information transmission capacity of the network with the network invariants, such as the node degree. 2. Methods and model. The starting point in our approach is to define and to analytically solve the ...

  11. Neural Network for Optimization of Existing Control Systems

    DEFF Research Database (Denmark)

    Madsen, Per Printz


    The purpose of this paper is to develop methods to use Neural Network based Controllers (NNC) as an optimization tool for existing control systems.......The purpose of this paper is to develop methods to use Neural Network based Controllers (NNC) as an optimization tool for existing control systems....

  12. Analysis of Basic Transmission Networks for Integrated Ship Control Systems

    DEFF Research Database (Denmark)

    Hansen, T.N.; Granum-Jensen, M.


    Description of a computer network for Integrated Ship Control Systems which is going to be developed as part of an EC-project. Today equipment of different make are not able to communicate with each other because most often each supplier of ISC systems has got their own proprietary network.....

  13. Encouraging Autonomy through the Use of a Social Networking System (United States)

    Leis, Adrian


    The use of social networking systems has enabled communication to occur around the globe almost instantly, with news about various events being spread around the world as they happen. There has also been much interest in the benefits and disadvantages the use of such social networking systems may bring for education. This paper reports on the use…

  14. Distributed control of networked Lur’e systems

    NARCIS (Netherlands)

    Zhang, Fan


    In this thesis we systematically study distributed control of networked Lur'e systems, specifically, robust synchronization problems and cooperative robust output regulation problems. In such nonlinear multi-agent networks, the model of each agent dynamics is taken as a Lur'e system that consists of

  15. Using Critical Systems thinking to Improve Student Performance in Networking


    Albertus G. Joubert; Roelien Goede


    This paper explores how Critical Systems Thinking and Action Research can be used to improve student performance in Networking. When describing a system from a systems thinking perspective, the following aspects can be identified: the total system performance, the systems environment, the resources, the components and the management of the system. Following the history of system thinking we observe three emerged methodologies namely, hard systems, soft systems, and critical systems. This pape...

  16. Complex Networks/Foundations of Information Systems (United States)


    Random Network (ex: Mobile Ad Hoc) Hybrid Network (Mesh) Deterministic Routing (ex: OSPF) Hybrid Routing (ex: OLSR) Random Protocol...10 - 2 10 - 1 100 Transmit power to noise ratio, P/N0, dB B it E rr o r R a te ( B E R ) BPSK signals, CDMA (L = 16), ds, d = 100m, UAV height = 1Km

  17. Distributed Robust Optimization in Networked System. (United States)

    Wang, Shengnan; Li, Chunguang


    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.

  18. A comparison of queueing, cluster and distributed computing systems (United States)

    Kaplan, Joseph A.; Nelson, Michael L.


    Using workstation clusters for distributed computing has become popular with the proliferation of inexpensive, powerful workstations. Workstation clusters offer both a cost effective alternative to batch processing and an easy entry into parallel computing. However, a number of workstations on a network does not constitute a cluster. Cluster management software is necessary to harness the collective computing power. A variety of cluster management and queuing systems are compared: Distributed Queueing Systems (DQS), Condor, Load Leveler, Load Balancer, Load Sharing Facility (LSF - formerly Utopia), Distributed Job Manager (DJM), Computing in Distributed Networked Environments (CODINE), and NQS/Exec. The systems differ in their design philosophy and implementation. Based on published reports on the different systems and conversations with the system's developers and vendors, a comparison of the systems are made on the integral issues of clustered computing.

  19. Method for designing networking adaptive interactive hybrid systems

    NARCIS (Netherlands)

    Kester, L. J.H.M.


    Advances in network technologies enable distributed systems, operating in complex physical environments, to co-ordinate their activities over larger areas within shorter time intervals. Some envisioned application domains for such systems are defence, crisis management, traffic management and public

  20. Networked Adaptive Interactive Hybrid Systems (NAIHS) for multiplatform engagement capability

    NARCIS (Netherlands)

    Kester, L.J.H.M.


    Advances in network technologies enable distributed systems, operating in complex physical environments, to coordinate their activities over larger areas within shorter time intervals. Some envisioned application domains for such systems are defence, crisis management, traffic management and public

  1. Creating networking adaptive interactive hybrid systems : A methodic approach

    NARCIS (Netherlands)

    Kester, L.J.


    Advances in network technologies enable distributed systems, operating in complex physical environments, to coordinate their activities over larger areas within shorter time intervals. Some envisioned application domains for such systems are defense, crisis management, traffic management, public

  2. parallelization, Hadoop, Google File Systems, Map Reduce, Distributed File System


    Jitendra Saxena; Aditya Goel


    Eminence of service is a extremely significant and critical concern for maintaining optical network with respect signal degradation. Queuing theory is an vital parameter to maintain voice video and data eminence of service. The network consists of different type of eminence of service model with priority of service with special reference to delay, speed and jitter

  3. Bio-Inspired Networking — Self-Organizing Networked Embedded Systems (United States)

    Dressler, Falko

    The turn to nature has brought us many unforeseen great concepts and solutions. This course seems to hold on for many research domains. In this article, we study the applicability of biological mechanisms and techniques in the domain of communications. In particular, we study the behavior and the challenges in networked embedded systems that are meant to self-organize in large groups of nodes. Application examples include wireless sensor networks and sensor/actuator networks. Based on a review of the needs and requirements in such networks, we study selected bio-inspired networking approaches that claim to outperform other methods in specific domains. We study mechanisms in swarm intelligence, the artificial immune system, and approaches based on investigations on the cellular signaling pathways. As a major conclusion, we derive that bio-inspired networking techniques do have advantages compared to engineering methods. Nevertheless, selection and employment must be done carefully to achieve the desired performance gains.

  4. Network Management System for Tactical Mobile Ad Hoc Network Segments (United States)


    Protocol UFO UHF Follow-On UHF Ultra High Frequency USB Universal Serial Bus VHF Very High Frequency VIRT Valuable Information at the Right Time...military satellite system known as the UHF Follow-on system ( UFO ) only provides capacity for 600 concurrent users. DoD users also have commercial

  5. Weighted Complex Network Analysis of Shanghai Rail Transit System

    Directory of Open Access Journals (Sweden)

    Yingying Xing


    Full Text Available With increasing passenger flows and construction scale, Shanghai rail transit system (RTS has entered a new era of networking operation. In addition, the structure and properties of the RTS network have great implications for urban traffic planning, design, and management. Thus, it is necessary to acquire their network properties and impacts. In this paper, the Shanghai RTS, as well as passenger flows, will be investigated by using complex network theory. Both the topological and dynamic properties of the RTS network are analyzed and the largest connected cluster is introduced to assess the reliability and robustness of the RTS network. Simulation results show that the distribution of nodes strength exhibits a power-law behavior and Shanghai RTS network shows a strong weighted rich-club effect. This study also indicates that the intentional attacks are more detrimental to the RTS network than to the random weighted network, but the random attacks can cause slightly more damage to the random weighted network than to the RTS network. Our results provide a richer view of complex weighted networks in real world and possibilities of risk analysis and policy decisions for the RTS operation department.

  6. Development of a model for assessing the impact of information assurance functionality on secure messaging system performance (United States)

    Belur, Sheela V.; Gloster, Jonathan


    An analytical performance model for a generic secure messaging system is formulated as a multi-class queuing network. The model includes assessment of the impact of security features such as secret key encryption/ decryption, signature generation/verification, and certificate validation, on overall performance. Findings of sensitivity analysis with respect to message rate, WAN transmission link, SSL encryption, message size, and distance between servers is also presented. Finally, the description of how the model can be adopted for making performance based architectural design options is outlined.

  7. Network analysis and synthesis a modern systems theory approach

    CERN Document Server

    Anderson, Brian D O


    Geared toward upper-level undergraduates and graduate students, this book offers a comprehensive look at linear network analysis and synthesis. It explores state-space synthesis as well as analysis, employing modern systems theory to unite the classical concepts of network theory. The authors stress passive networks but include material on active networks. They avoid topology in dealing with analysis problems and discuss computational techniques. The concepts of controllability, observability, and degree are emphasized in reviewing the state-variable description of linear systems. Explorations

  8. Scalable Hierarchical Network Management System for Displaying Network Information in Three Dimensions (United States)

    George, Jude (Inventor); Schlecht, Leslie (Inventor); McCabe, James D. (Inventor); LeKashman, John Jr. (Inventor)


    A network management system has SNMP agents distributed at one or more sites, an input output module at each site, and a server module located at a selected site for communicating with input output modules, each of which is configured for both SNMP and HNMP communications. The server module is configured exclusively for HNMP communications, and it communicates with each input output module according to the HNMP. Non-iconified, informationally complete views are provided of network elements to aid in network management.

  9. WDM Systems and Networks Modeling, Simulation, Design and Engineering

    CERN Document Server

    Ellinas, Georgios; Roudas, Ioannis


    WDM Systems and Networks: Modeling, Simulation, Design and Engineering provides readers with the basic skills, concepts, and design techniques used to begin design and engineering of optical communication systems and networks at various layers. The latest semi-analytical system simulation techniques are applied to optical WDM systems and networks, and a review of the various current areas of optical communications is presented. Simulation is mixed with experimental verification and engineering to present the industry as well as state-of-the-art research. This contributed volume is divided into three parts, accommodating different readers interested in various types of networks and applications. The first part of the book presents modeling approaches and simulation tools mainly for the physical layer including transmission effects, devices, subsystems, and systems), whereas the second part features more engineering/design issues for various types of optical systems including ULH, access, and in-building system...

  10. Network theory and its applications in economic systems (United States)

    Huang, Xuqing

    This dissertation covers the two major parts of my Ph.D. research: i) developing theoretical framework of complex networks; and ii) applying complex networks models to quantitatively analyze economics systems. In part I, we focus on developing theories of interdependent networks, which includes two chapters: 1) We develop a mathematical framework to study the percolation of interdependent networks under targeted-attack and find that when the highly connected nodes are protected and have lower probability to fail, in contrast to single scale-free (SF) networks where the percolation threshold pc = 0, coupled SF networks are significantly more vulnerable with pc significantly larger than zero. 2) We analytically demonstrates that clustering, which quantifies the propensity for two neighbors of the same vertex to also be neighbors of each other, significantly increases the vulnerability of the system. In part II, we apply the complex networks models to study economics systems, which also includes two chapters: 1) We study the US corporate governance network, in which nodes representing directors and links between two directors representing their service on common company boards, and propose a quantitative measure of information and influence transformation in the network. Thus we are able to identify the most influential directors in the network. 2) We propose a bipartite networks model to simulate the risk propagation process among commercial banks during financial crisis. With empirical bank's balance sheet data in 2007 as input to the model, we find that our model efficiently identifies a significant portion of the actual failed banks reported by Federal Deposit Insurance Corporation during the financial crisis between 2008 and 2011. The results suggest that complex networks model could be useful for systemic risk stress testing for financial systems. The model also identifies that commercial rather than residential real estate assets are major culprits for the

  11. The Accounting Network: how financial institutions react to systemic crisis

    CERN Document Server

    Flori, Andrea; Puliga, Michelangelo; Chessa, Alessandro; Pammolli, Fabio


    The role of Network Theory in the study of the financial crisis has been widely spotted in the latest years. It has been shown how the network topology and the dynamics running on top of it can trigger the outbreak of large systemic crisis. Following this methodological perspective we introduce here the Accounting Network, i.e. the network we can extract through vector similarities techniques from companies' financial statements. We build the Accounting Network on a large database of worldwide banks in the period 2001-2013, covering the onset of the global financial crisis of mid-2007. After a careful data cleaning, we apply a quality check in the construction of the network, introducing a parameter (the Quality Ratio) capable of trading off the size of the sample (coverage) and the representativeness of the financial statements (accuracy). We compute several basic network statistics and check, with the Louvain community detection algorithm, for emerging communities of banks. Remarkably enough sensible region...

  12. Modelling pedestrian travel time and the design of facilities: a queuing approach.

    Directory of Open Access Journals (Sweden)

    Khalidur Rahman

    Full Text Available Pedestrian movements are the consequence of several complex and stochastic facts. The modelling of pedestrian movements and the ability to predict the travel time are useful for evaluating the performance of a pedestrian facility. However, only a few studies can be found that incorporate the design of the facility, local pedestrian body dimensions, the delay experienced by the pedestrians, and level of service to the pedestrian movements. In this paper, a queuing based analytical model is developed as a function of relevant determinants and functional factors to predict the travel time on pedestrian facilities. The model can be used to assess the overall serving rate or performance of a facility layout and correlate it to the level of service that is possible to provide the pedestrians. It has also the ability to provide a clear suggestion on the designing and sizing of pedestrian facilities. The model is empirically validated and is found to be a robust tool to understand how well a particular walking facility makes possible comfort and convenient pedestrian movements. The sensitivity analysis is also performed to see the impact of some crucial parameters of the developed model on the performance of pedestrian facilities.

  13. Rational function systems and electrical networks with multiparameters

    CERN Document Server

    Lu, KaiSheng


    To overcome the problems of system theory and network theory over real field, this book uses matrices over the field F(z) of rational functions in multiparameters describing coefficient matrices of systems and networks and makes systems and network description over F(z) and researches their structural properties: reducible condition of a class of matrices over F(z) and their characteristic polynomial; type1 matrix and two basic properties; variable replacement conditions for independent parameters; structural controllability and observability of linear systems over F(z); separability, reducibi

  14. Increased Efficiency of Face Recognition System using Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Rajani Muraleedharan


    Full Text Available This research was inspired by the need of a flexible and cost effective biometric security system. The flexibility of the wireless sensor network makes it a natural choice for data transmission. Swarm intelligence (SI is used to optimize routing in distributed time varying network. In this paper, SI maintains the required bit error rate (BER for varied channel conditions while consuming minimal energy. A specific biometric, the face recognition system, is discussed as an example. Simulation shows that the wireless sensor network is efficient in energy consumption while keeping the transmission accuracy, and the wireless face recognition system is competitive to the traditional wired face recognition system in classification accuracy.

  15. Synthesis of recurrent neural networks for dynamical system simulation. (United States)

    Trischler, Adam P; D'Eleuterio, Gabriele M T


    We review several of the most widely used techniques for training recurrent neural networks to approximate dynamical systems, then describe a novel algorithm for this task. The algorithm is based on an earlier theoretical result that guarantees the quality of the network approximation. We show that a feedforward neural network can be trained on the vector-field representation of a given dynamical system using backpropagation, then recast it as a recurrent network that replicates the original system's dynamics. After detailing this algorithm and its relation to earlier approaches, we present numerical examples that demonstrate its capabilities. One of the distinguishing features of our approach is that both the original dynamical systems and the recurrent networks that simulate them operate in continuous time. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Systemic risk analysis in reconstructed economic and financial networks

    CERN Document Server

    Cimini, Giulio; Gabrielli, Andrea; Garlaschelli, Diego


    The assessment of fundamental properties for economic and financial systems, such as systemic risk, is systematically hindered by privacy issues$-$that put severe limitations on the available information. Here we introduce a novel method to reconstruct partially-accessible networked systems of this kind. The method is based on the knowledge of the fitnesses, $i.e.$, intrinsic node-specific properties, and of the number of connections of only a limited subset of nodes. Such information is used to calibrate a directed configuration model which can generate ensembles of networks intended to represent the real system, so that the real network properties can be estimated within the generated ensemble in terms of mean values of the observables. Here we focus on estimating those properties that are commonly used to measure the network resilience to shock and crashes. Tests on both artificial and empirical networks shows that the method is remarkably robust with respect to the limitedness of the information available...

  17. A network-based dynamical ranking system for competitive sports (United States)

    Motegi, Shun; Masuda, Naoki


    From the viewpoint of networks, a ranking system for players or teams in sports is equivalent to a centrality measure for sports networks, whereby a directed link represents the result of a single game. Previously proposed network-based ranking systems are derived from static networks, i.e., aggregation of the results of games over time. However, the score of a player (or team) fluctuates over time. Defeating a renowned player in the peak performance is intuitively more rewarding than defeating the same player in other periods. To account for this factor, we propose a dynamic variant of such a network-based ranking system and apply it to professional men's tennis data. We derive a set of linear online update equations for the score of each player. The proposed ranking system predicts the outcome of the future games with a higher accuracy than the static counterparts.

  18. A network-based dynamical ranking system for competitive sports. (United States)

    Motegi, Shun; Masuda, Naoki


    From the viewpoint of networks, a ranking system for players or teams in sports is equivalent to a centrality measure for sports networks, whereby a directed link represents the result of a single game. Previously proposed network-based ranking systems are derived from static networks, i.e., aggregation of the results of games over time. However, the score of a player (or team) fluctuates over time. Defeating a renowned player in the peak performance is intuitively more rewarding than defeating the same player in other periods. To account for this factor, we propose a dynamic variant of such a network-based ranking system and apply it to professional men's tennis data. We derive a set of linear online update equations for the score of each player. The proposed ranking system predicts the outcome of the future games with a higher accuracy than the static counterparts.

  19. The Reliability of Wireless Sensor Network on Pipeline Monitoring System

    Directory of Open Access Journals (Sweden)

    Hafizh Prihtiadi


    Full Text Available The wireless sensor network (WSN is an attractive technology, which combines embedded systems and communication networks making them more efficient and effective. Currently, WSNs have been developed for various monitoring applications. In this research, a wireless mesh network for a pipeline monitoring system was designed and developed. Sensor nodes were placed at each branch in the pipe system. Some router fails were simulated and the response of each node in the network was evaluated. Three different scenarios were examined to test the data transmission performance. The results proved that the wireless mesh network was reliable and robust. The system is able to perform link reconfiguration, automatic routing and safe data transmission from the beginning node to the end node.

  20. Optimal design of network distribution systems

    Directory of Open Access Journals (Sweden)

    U. Passy


    Full Text Available The problem of finding the optimal distribution of pressure drop over a network is solved via an unconstrained gradient type algorithm. The developed algorithm is computationally attractive. Problems with several hundred variables and constraints were solved.

  1. Network system effects of mileage fee. (United States)


    This project presents a comprehensive investigation about the network effects of MF to facilitate the : developments of proper MF policies. After a practice scan and a review of the recent literature on MF, a multi-class mathematical programming with...

  2. Operation of International Monitoring System Network (United States)

    Nikolova, Svetlana; Araujo, Fernando; Aktas, Kadircan; Malakhova, Marina; Otsuka, Riyo; Han, Dongmei; Assef, Thierry; Nava, Elisabetta; Mickevicius, Sigitas; Agrebi, Abdelouaheb


    The IMS is a globally distributed network of monitoring facilities using sensors from four technologies: seismic, hydroacoustic, infrasound and radionuclide. It is designed to detect the seismic and acoustic waves produced by nuclear test explosions and the subsequently released radioactive isotopes. Monitoring stations transmit their data to the IDC in Vienna, Austria, over a global private network known as the GCI. Since 2013, the data availability (DA) requirements for IMS stations account for quality of the data, meaning that in calculation of data availability data should be exclude if: - there is no input from sensor (SHI technology); - the signal consists of constant values (SHI technology); Even more strict are requirements for the DA of the radionuclide (particulate and noble gas) stations - received data have to be analyzed, reviewed and categorized by IDC analysts. In order to satisfy the strict data and network availability requirements of the IMS Network, the operation of the facilities and the GCI are managed by IDC Operations. Operations has following main functions: - to ensure proper operation and functioning of the stations; - to ensure proper operation and functioning of the GCI; - to ensure efficient management of the stations in IDC; - to provide network oversight and incident management. At the core of the IMS Network operations are a series of tools for: monitoring the stations' state of health and data quality, troubleshooting incidents, communicating with internal and external stakeholders, and reporting. The new requirements for data availability increased the importance of the raw data quality monitoring. This task is addressed by development of additional tools for easy and fast identifying problems in data acquisition, regular activities to check compliance of the station parameters with acquired data by scheduled calibration of the seismic network, review of the samples by certified radionuclide laboratories. The DA for the networks of

  3. Data storage system for wireless sensor networks


    Sacramento, David


    Dissertação de mestrado, Engenharia Informática, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2015 Wireless sensor networks (WSNs) are starting to have a high impact on our societies and, for next generation WSNs to become more integrated with the Internet, researchers recently proposed to embed Internet Protocol (IP) v6 into such very constrained networks. Also, Constrained Application Protocol (CoAP) and Observe have been proposed for RESTful services to be pr...

  4. Power Restoration in Medium Voltage Network Using Multiagent System

    Directory of Open Access Journals (Sweden)

    Miroslav Kovac


    Full Text Available The article describes a novel approach to a power restoration in medium voltage power distribution network. It focuses primary at searching of a new network configuration enabling to minimalize the size of faulted area and to restore the power for the highest possible number of loads. It describes characteristic features of medium voltage power distribution network and discusses the implementation of the presented approach in existing networks. A software tool, developed by the authors, including physical simulation of model network and its autonomous control system is described. An example of fault situation in a virtual distribution network is presented. Afterwards, the solution of restoration problem by proposed multiagent system is simulated using the software tool described in the paper.

  5. A Case for Open Network Health Systems: Systems as Networks in Public Mental Health

    Directory of Open Access Journals (Sweden)

    Michael Grant Rhodes


    Full Text Available Increases in incidents involving so-called confused persons have brought attention to the potential costs of recent changes to public mental health (PMH services in the Netherlands. Decentralized under the (Community Participation Act (2014, local governments must find resources to compensate for reduced central funding to such services or “innovate.” But innovation, even when pressure for change is intense, is difficult. This perspective paper describes experience during and after an investigation into a particularly violent incident and murder. The aim was to provide recommendations to improve the functioning of local PMH services. The investigation concluded that no specific failure by an individual professional or service provider facility led to the murder. Instead, also as a result of the Participation Act that severed communication lines between individuals and organizations, information sharing failures were likely to have reduced system level capacity to identify risks. The methods and analytical frameworks employed to reach this conclusion, also lead to discussion as to the plausibility of an unconventional solution. If improving communication is the primary problem, non-hierarchical information, and organizational networks arise as possible and innovative system solutions. The proposal for debate is that traditional “health system” definitions, literature and narratives, and operating assumptions in public (mental health are ‘locked in’ constraining technical and organization innovations. If we view a “health system” as an adaptive system of economic and social “networks,” it becomes clear that the current orthodox solution, the so-called integrated health system, typically results in a “centralized hierarchical” or “tree” network. An overlooked alternative that breaks out of the established policy narratives is the view of a ‘health systems’ as a non-hierarchical organizational structure or

  6. Operation of the International Monitoring System Network (United States)

    Araujo, Fernando; Castillo, Enrique; Nikolova, Svetlana; Daly, Timothy


    The IMS is a globally distributed network of monitoring facilities using sensors from four technologies. It is designed to detect the seismic and acoustic waves produced by nuclear test explosions and the subsequently released radioactive isotopes. Monitoring stations transmit their data to the IDC in Vienna, Austria, over a global private network known as the Global Communications Infrastructure (GCI). In order to satisfy the strict data and network availability requirements of the IMS Network, the operation of the facilities and the GCI are managed by IDC Operations. IDC Operations has three functions: the first is to ensure proper operation and functioning of the stations, the second to ensure proper operation and functioning of the GCI, and the third, handled by the IDC Operations Centre is to provide network oversight and incident management. At the core of the IMS Network operations are a series of tools for: monitoring the stations' state of health and data quality, troubleshooting incidents, communicating with internal and external stakeholders, and reporting. An overview of the tools currently used by IDC Operations as well as those under development will be presented. This will include an outline of the IDC's strategy for operations and its dependence on entities both inside and outside the CTBTO.

  7. STIMULUS: End-System Network Interface Controller for 100 Gb/s Wide Area Networks

    Energy Technology Data Exchange (ETDEWEB)

    Zarkesh-Ha, Payman [University of New Mexico


    The main goal of this research grant is to develop a system-level solution leveraging novel technologies that enable network communications at 100 Gb/s or beyond. University of New Mexico in collaboration with Acadia Optronics LLC has been working on this project to develop the 100 Gb/s Network Interface Controller (NIC) under this Department of Energy (DOE) grant.

  8. Intrusions Detection System Based on Ubiquitous Network Nodes


    Sellami, Lynda; IDOUGHI, Djilali; Baadache, Abderahmane


    Ubiquitous computing allows to make data and services within the reach of users anytime and anywhere. This makes ubiquitous networks vulnerable to attacks coming from either inside or outside the network. To ensure and enhance networks security, several solutions have been implemented. These solutions are inefficient and or incomplete. Solving these challenges in security with new requirement of Ubicomp, could provide a potential future for such systems towards better mobility and higher conf...


    Directory of Open Access Journals (Sweden)



    Full Text Available In this research, a hierarchical off-line anomaly network intrusion detection system based on Distributed Time-Delay Artificial Neural Network is introduced. This research aims to solve a hierarchical multi class problem in which the type of attack (DoS, U2R, R2L and Probe attack detected by dynamic neural network. The results indicate that dynamic neural nets (Distributed Time-Delay Artificial Neural Network can achieve a high detection rate, where the overall accuracy classification rate average is equal to 97.24%.


    Directory of Open Access Journals (Sweden)

    N. A. Bazhayev


    Full Text Available We consider the wireless network under attack, aimed at "broadcast storm" initiation, in order to determine the availability of stand-alone units and the ability to carry out their functional tasks under information exposure. We determine a set of conditions for such type of attacks on the part of potential information interloper. The functional analysis of the systems based on wireless technology is made. We examine the remote device of a self-organizing wireless network as a queuing system M/M/1/n. Model dependencies are shown for normal system performance and at information exposure on the part of potential information interloper. Analytical simulation of wireless network functioning is carried out in the normal mode and under the attack aimed at "broadcast storm" initiation. An experiment is described which provides statistical information on operation of network remote devices. We present experiment results on carrying out attack at typical system transferring data by broabcast net scanning package at different noise intensities on the part of information interloper. The proposed model can be used to determine the technical characteristics of wireless ad-hoc network, develop recommendations for node configuration, aimed at countering "broadcast storm".

  11. Application of wireless sensor network technology in logistics information system (United States)

    Xu, Tao; Gong, Lina; Zhang, Wei; Li, Xuhong; Wang, Xia; Pan, Wenwen


    This paper introduces the basic concepts of active RFID (WSN-ARFID) based on wireless sensor networks and analyzes the shortcomings of the existing RFID-based logistics monitoring system. Integrated wireless sensor network technology and the scrambling point of RFID technology. A new real-time logistics detection system based on WSN and RFID, a model of logistics system based on WSN-ARFID is proposed, and the feasibility of this technology applied to logistics field is analyzed.

  12. Social network analysis and network connectedness analysis for industrial symbiotic systems: model development and case study (United States)

    Zhang, Yan; Zheng, Hongmei; Chen, Bin; Yang, Naijin


    An important and practical pattern of industrial symbiosis is rapidly developing: eco-industrial parks. In this study, we used social network analysis to study the network connectedness (i.e., the proportion of the theoretical number of connections that had been achieved) and related attributes of these hybrid ecological and industrial symbiotic systems. This approach provided insights into details of the network's interior and analyzed the overall degree of connectedness and the relationships among the nodes within the network. We then characterized the structural attributes of the network and subnetwork nodes at two levels (core and periphery), thereby providing insights into the operational problems within each eco-industrial park. We chose ten typical ecoindustrial parks in China and around the world and compared the degree of network connectedness of these systems that resulted from exchanges of products, byproducts, and wastes. By analyzing the density and nodal degree, we determined the relative power and status of the nodes in these networks, as well as other structural attributes such as the core-periphery structure and the degree of sub-network connectedness. The results reveal the operational problems created by the structure of the industrial networks and provide a basis for improving the degree of completeness, thereby increasing their potential for sustainable development and enriching the methods available for the study of industrial symbiosis.

  13. Precise Network Modeling of Systems Genetics Data Using the Bayesian Network Webserver. (United States)

    Ziebarth, Jesse D; Cui, Yan


    The Bayesian Network Webserver (BNW, ) is an integrated platform for Bayesian network modeling of biological datasets. It provides a web-based network modeling environment that seamlessly integrates advanced algorithms for probabilistic causal modeling and reasoning with Bayesian networks. BNW is designed for precise modeling of relatively small networks that contain less than 20 nodes. The structure learning algorithms used by BNW guarantee the discovery of the best (most probable) network structure given the data. To facilitate network modeling across multiple biological levels, BNW provides a very flexible interface that allows users to assign network nodes into different tiers and define the relationships between and within the tiers. This function is particularly useful for modeling systems genetics datasets that often consist of multiscalar heterogeneous genotype-to-phenotype data. BNW enables users to, within seconds or minutes, go from having a simply formatted input file containing a dataset to using a network model to make predictions about the interactions between variables and the potential effects of experimental interventions. In this chapter, we will introduce the functions of BNW and show how to model systems genetics datasets with BNW.

  14. Intrusion Detection System Using Deep Neural Network for In-Vehicle Network Security (United States)

    Kang, Min-Joo


    A novel intrusion detection system (IDS) using a deep neural network (DNN) is proposed to enhance the security of in-vehicular network. The parameters building the DNN structure are trained with probability-based feature vectors that are extracted from the in-vehicular network packets. For a given packet, the DNN provides the probability of each class discriminating normal and attack packets, and, thus the sensor can identify any malicious attack to the vehicle. As compared to the traditional artificial neural network applied to the IDS, the proposed technique adopts recent advances in deep learning studies such as initializing the parameters through the unsupervised pre-training of deep belief networks (DBN), therefore improving the detection accuracy. It is demonstrated with experimental results that the proposed technique can provide a real-time response to the attack with a significantly improved detection ratio in controller area network (CAN) bus. PMID:27271802

  15. Intrusion Detection System Using Deep Neural Network for In-Vehicle Network Security. (United States)

    Kang, Min-Joo; Kang, Je-Won


    A novel intrusion detection system (IDS) using a deep neural network (DNN) is proposed to enhance the security of in-vehicular network. The parameters building the DNN structure are trained with probability-based feature vectors that are extracted from the in-vehicular network packets. For a given packet, the DNN provides the probability of each class discriminating normal and attack packets, and, thus the sensor can identify any malicious attack to the vehicle. As compared to the traditional artificial neural network applied to the IDS, the proposed technique adopts recent advances in deep learning studies such as initializing the parameters through the unsupervised pre-training of deep belief networks (DBN), therefore improving the detection accuracy. It is demonstrated with experimental results that the proposed technique can provide a real-time response to the attack with a significantly improved detection ratio in controller area network (CAN) bus.

  16. Intrusion Detection System Using Deep Neural Network for In-Vehicle Network Security.

    Directory of Open Access Journals (Sweden)

    Min-Joo Kang

    Full Text Available A novel intrusion detection system (IDS using a deep neural network (DNN is proposed to enhance the security of in-vehicular network. The parameters building the DNN structure are trained with probability-based feature vectors that are extracted from the in-vehicular network packets. For a given packet, the DNN provides the probability of each class discriminating normal and attack packets, and, thus the sensor can identify any malicious attack to the vehicle. As compared to the traditional artificial neural network applied to the IDS, the proposed technique adopts recent advances in deep learning studies such as initializing the parameters through the unsupervised pre-training of deep belief networks (DBN, therefore improving the detection accuracy. It is demonstrated with experimental results that the proposed technique can provide a real-time response to the attack with a significantly improved detection ratio in controller area network (CAN bus.

  17. Heterogeneous information network model for equipment-standard system (United States)

    Yin, Liang; Shi, Li-Chen; Zhao, Jun-Yan; Du, Song-Yang; Xie, Wen-Bo; Yuan, Fei; Chen, Duan-Bing


    Entity information network is used to describe structural relationships between entities. Taking advantage of its extension and heterogeneity, entity information network is more and more widely applied to relationship modeling. Recent years, lots of researches about entity information network modeling have been proposed, while seldom of them concentrate on equipment-standard system with properties of multi-layer, multi-dimension and multi-scale. In order to efficiently deal with some complex issues in equipment-standard system such as standard revising, standard controlling, and production designing, a heterogeneous information network model for equipment-standard system is proposed in this paper. Three types of entities and six types of relationships are considered in the proposed model. Correspondingly, several different similarity-measuring methods are used in the modeling process. The experiments show that the heterogeneous information network model established in this paper can reflect relationships between entities accurately. Meanwhile, the modeling process has a good performance on time consumption.

  18. Design and Simulation Analysis for Integrated Vehicle Chassis-Network Control System Based on CAN Network

    Directory of Open Access Journals (Sweden)

    Wei Yu


    Full Text Available Due to the different functions of the system used in the vehicle chassis control, the hierarchical control strategy also leads to many kinds of the network topology structure. According to the hierarchical control principle, this research puts forward the integrated control strategy of the chassis based on supervision mechanism. The purpose is to consider how the integrated control architecture affects the control performance of the system after the intervention of CAN network. Based on the principle of hierarchical control and fuzzy control, a fuzzy controller is designed, which is used to monitor and coordinate the ESP, AFS, and ARS. And the IVC system is constructed with the upper supervisory controller and three subcontrol systems on the Simulink platform. The network topology structure of IVC is proposed, and the IVC communication matrix based on CAN network communication is designed. With the common sensors and the subcontrollers as the CAN network independent nodes, the network induced delay and packet loss rate on the system control performance are studied by simulation. The results show that the simulation method can be used for designing the communication network of the vehicle.

  19. Synchronization in Complex Networks of Nonlinear Dynamical Systems

    CERN Document Server

    Wu, Chai Wah


    This book brings together two emerging research areas: synchronization in coupled nonlinear systems and complex networks, and study conditions under which a complex network of dynamical systems synchronizes. While there are many texts that study synchronization in chaotic systems or properties of complex networks, there are few texts that consider the intersection of these two very active and interdisciplinary research areas. The main theme of this book is that synchronization conditions can be related to graph theoretical properties of the underlying coupling topology. The book introduces ide

  20. Wireless Sensor Network Metrics for Real-Time Systems (United States)


    layer standard [119]. Zigbee is initially targeted at energy management and efficiency, home automation , building automation, and industrial automation...Hong-Hee Lee, “Network-based fire-detection system via con- troller area network for smart home automation ,” IEEE Transactions on Consumer Electronics

  1. Transport network extensions for accessibility analysis in geographic information systems

    NARCIS (Netherlands)

    Jong, Tom de; Tillema, T.


    In many developed countries high quality digital transport networks are available for GIS based analysis. Partly this is due to the requirements of route planning software for internet and car navigation systems. Properties of these networks consist among others of road quality attributes,

  2. Data and Network Science for Noisy Heterogeneous Systems (United States)

    Rider, Andrew Kent


    Data in many growing fields has an underlying network structure that can be taken advantage of. In this dissertation we apply data and network science to problems in the domains of systems biology and healthcare. Data challenges in these fields include noisy, heterogeneous data, and a lack of ground truth. The primary thesis of this work is that…

  3. Available Resources for Reconfigurable Systems in 5G Networks

    DEFF Research Database (Denmark)

    Rodríguez Páez, Juan Sebastián; Vegas Olmos, Juan José


    In this paper, the concept of a Radio-over-Fiber based Centralized Radio Access Network is explained and analyzed, in order to identify a set of resources within the network that can be used as a base in the design of reconfigurable systems. This analysis is then used to design a different reconf...

  4. The middleware architecture supports heterogeneous network systems for module-based personal robot system (United States)

    Choo, Seongho; Li, Vitaly; Choi, Dong Hee; Jung, Gi Deck; Park, Hong Seong; Ryuh, Youngsun


    On developing the personal robot system presently, the internal architecture is every module those occupy separated functions are connected through heterogeneous network system. This module-based architecture supports specialization and division of labor at not only designing but also implementation, as an effect of this architecture, it can reduce developing times and costs for modules. Furthermore, because every module is connected among other modules through network systems, we can get easy integrations and synergy effect to apply advanced mutual functions by co-working some modules. In this architecture, one of the most important technologies is the network middleware that takes charge communications among each modules connected through heterogeneous networks systems. The network middleware acts as the human nerve system inside of personal robot system; it relays, transmits, and translates information appropriately between modules that are similar to human organizations. The network middleware supports various hardware platform, heterogeneous network systems (Ethernet, Wireless LAN, USB, IEEE 1394, CAN, CDMA-SMS, RS-232C). This paper discussed some mechanisms about our network middleware to intercommunication and routing among modules, methods for real-time data communication and fault-tolerant network service. There have designed and implemented a layered network middleware scheme, distributed routing management, network monitoring/notification technology on heterogeneous networks for these goals. The main theme is how to make routing information in our network middleware. Additionally, with this routing information table, we appended some features. Now we are designing, making a new version network middleware (we call 'OO M/W') that can support object-oriented operation, also are updating program sources itself for object-oriented architecture. It is lighter, faster, and can support more operation systems and heterogeneous network systems, but other general

  5. Applying Model Based Systems Engineering to NASA's Space Communications Networks (United States)

    Bhasin, Kul; Barnes, Patrick; Reinert, Jessica; Golden, Bert


    System engineering practices for complex systems and networks now require that requirement, architecture, and concept of operations product development teams, simultaneously harmonize their activities to provide timely, useful and cost-effective products. When dealing with complex systems of systems, traditional systems engineering methodology quickly falls short of achieving project objectives. This approach is encumbered by the use of a number of disparate hardware and software tools, spreadsheets and documents to grasp the concept of the network design and operation. In case of NASA's space communication networks, since the networks are geographically distributed, and so are its subject matter experts, the team is challenged to create a common language and tools to produce its products. Using Model Based Systems Engineering methods and tools allows for a unified representation of the system in a model that enables a highly related level of detail. To date, Program System Engineering (PSE) team has been able to model each network from their top-level operational activities and system functions down to the atomic level through relational modeling decomposition. These models allow for a better understanding of the relationships between NASA's stakeholders, internal organizations, and impacts to all related entities due to integration and sustainment of existing systems. Understanding the existing systems is essential to accurate and detailed study of integration options being considered. In this paper, we identify the challenges the PSE team faced in its quest to unify complex legacy space communications networks and their operational processes. We describe the initial approaches undertaken and the evolution toward model based system engineering applied to produce Space Communication and Navigation (SCaN) PSE products. We will demonstrate the practice of Model Based System Engineering applied to integrating space communication networks and the summary of its

  6. System-level Modeling of Wireless Integrated Sensor Networks

    DEFF Research Database (Denmark)

    Virk, Kashif M.; Hansen, Knud; Madsen, Jan


    Wireless integrated sensor networks have emerged as a promising infrastructure for a new generation of monitoring and tracking applications. In order to efficiently utilize the extremely limited resources of wireless sensor nodes, accurate modeling of the key aspects of wireless sensor networks...... is necessary so that system-level design decisions can be made about the hardware and the software (applications and real-time operating system) architecture of sensor nodes. In this paper, we present a SystemC-based abstract modeling framework that enables system-level modeling of sensor network behavior...... by modeling the applications, real-time operating system, sensors, processor, and radio transceiver at the sensor node level and environmental phenomena, including radio signal propagation, at the sensor network level. We demonstrate the potential of our modeling framework by simulating and analyzing a small...

  7. Using a Control System Ethernet Network as a Field Bus

    CERN Document Server

    De Van, William R; Lawson, Gregory S; Wagner, William H; Wantland, David M; Williams, Ernest


    A major component of a typical accelerator distributed control system (DCS) is a dedicated, large-scale local area communications network (LAN). The SNS EPICS-based control system uses a LAN based on the popular IEEE-802.3 set of standards (Ethernet). Since the control system network infrastructure is available throughout the facility, and since Ethernet-based controllers are readily available, it is tempting to use the control system LAN for "fieldbus" communications to low-level control devices (e.g. vacuum controllers; remote I/O). These devices may or may not be compatible with the high-level DCS protocols. This paper presents some of the benefits and risks of combining high-level DCS communications with low-level "field bus" communications on the same network, and describes measures taken at SNS to promote compatibility between devices connected to the control system network.

  8. CifNet network multi-well data management system (United States)

    Li, Ning; Wang, Mingchao; Cui, Jian; Wang, Jianqiang; Wang, Caizhi


    The CifNet network multi-well data management system is developed for 100MB or 1000MB local network environments which are used in Chinese oil industry. The kernel techniques of CifNet system include: 1, establishing a high efficient and low cost network multi-well data management architecture based on the General Logging Curve Theory and the Cif data format; 2, implementing efficient visit and transmission of multi-well data in C/S local network based on TCP/IP protocol; 3, ensuring the safety of multi-well data in store, visit and application based on Unix operating system security. By using CifNet system, the researcher in office or at home can visit curves of any borehole in any working area of any oilfield. The application foreground of CifNet system is also commented.

  9. Human metabolic network: reconstruction, simulation, and applications in systems biology. (United States)

    Wu, Ming; Chan, Christina


    Metabolism is crucial to cell growth and proliferation. Deficiency or alterations in metabolic functions are known to be involved in many human diseases. Therefore, understanding the human metabolic system is important for the study and treatment of complex diseases. Current reconstructions of the global human metabolic network provide a computational platform to integrate genome-scale information on metabolism. The platform enables a systematic study of the regulation and is applicable to a wide variety of cases, wherein one could rely on in silico perturbations to predict novel targets, interpret systemic effects, and identify alterations in the metabolic states to better understand the genotype-phenotype relationships. In this review, we describe the reconstruction of the human metabolic network, introduce the constraint based modeling approach to analyze metabolic networks, and discuss systems biology applications to study human physiology and pathology. We highlight the challenges and opportunities in network reconstruction and systems modeling of the human metabolic system.

  10. Submodularity in dynamics and control of networked systems

    CERN Document Server

    Clark, Andrew; Bushnell, Linda; Poovendran, Radha


    This book presents a framework for the control of networked systems utilizing submodular optimization techniques. The main focus is on selecting input nodes for the control of networked systems, an inherently discrete optimization problem with applications in power system stability, social influence dynamics, and the control of vehicle formations. The first part of the book is devoted to background information on submodular functions, matroids, and submodular optimization, and presents algorithms for distributed submodular optimization that are scalable to large networked systems. In turn, the second part develops a unifying submodular optimization approach to controlling networked systems based on multiple performance and controllability criteria. Techniques are introduced for selecting input nodes to ensure smooth convergence, synchronization, and robustness to environmental and adversarial noise. Submodular optimization is the first unifying approach towards guaranteeing both performance and controllabilit...

  11. An Efficient Multitask Scheduling Model for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Hongsheng Yin


    Full Text Available The sensor nodes of multitask wireless network are constrained in performance-driven computation. Theoretical studies on the data processing model of wireless sensor nodes suggest satisfying the requirements of high qualities of service (QoS of multiple application networks, thus improving the efficiency of network. In this paper, we present the priority based data processing model for multitask sensor nodes in the architecture of multitask wireless sensor network. The proposed model is deduced with the M/M/1 queuing model based on the queuing theory where the average delay of data packets passing by sensor nodes is estimated. The model is validated with the real data from the Huoerxinhe Coal Mine. By applying the proposed priority based data processing model in the multitask wireless sensor network, the average delay of data packets in a sensor nodes is reduced nearly to 50%. The simulation results show that the proposed model can improve the throughput of network efficiently.

  12. Model-based Compositional Design of Networked Control Systems (United States)


    systems such as tele- robots for surgery , implanted heart monitors, nanoscale di- agnostic instruments, digital protheses and other medical devices, as...exploration, surgery , search and rescue missions, hazardous environment and other various military applications. An n-degrees of freedom robotic manipulator...lives. Examples of these systems include process control, automotive systems, networked robotics , medical systems, electrical power grids and

  13. Network modelling of physical systems: a geometric approach

    NARCIS (Netherlands)

    van der Schaft, Arjan; Maschke, B.M.; Ortega, Romeo; Banos, A.; Lamnabhi-lagarrigue, F; Montoya, F.J.


    It is discussed how network modeling of lumped-parameter physical systems naturally leads to a geometrically defined class of systems, called port-controlled Hamiltonian systems (with dissipation). The structural properties of these systems are investigated, in particular the existence of Casimir

  14. Role of Network Topology in the Synchronization of Power Systems

    CERN Document Server

    Lozano, Sergi; Díaz-Guilera, Albert; 10.1140/epjb/e2012-30209-9


    We study synchronization dynamics in networks of coupled oscillators with bimodal distribution of natural frequencies. This setup can be interpreted as a simple model of frequency synchronization dynamics among generators and loads working in a power network. We derive the minimum coupling strength required to ensure global frequency synchronization. This threshold value can be efficiently found by solving a binary optimization problem, even for large networks. In order to validate our procedure, we compare its results with numerical simulations on a realistic network describing the European interconnected high-voltage electricity system, finding a very good agreement. Our synchronization threshold can be used to test the stability of frequency synchronization to link removals. As the threshold value changes only in very few cases when aplied to the European realistic network, we conclude that network is resilient in this regard. Since the threshold calculation depends on the local connectivity, it can also b...

  15. Decision support systems and methods for complex networks (United States)

    Huang, Zhenyu [Richland, WA; Wong, Pak Chung [Richland, WA; Ma, Jian [Richland, WA; Mackey, Patrick S [Richland, WA; Chen, Yousu [Richland, WA; Schneider, Kevin P [Seattle, WA


    Methods and systems for automated decision support in analyzing operation data from a complex network. Embodiments of the present invention utilize these algorithms and techniques not only to characterize the past and present condition of a complex network, but also to predict future conditions to help operators anticipate deteriorating and/or problem situations. In particular, embodiments of the present invention characterize network conditions from operation data using a state estimator. Contingency scenarios can then be generated based on those network conditions. For at least a portion of all of the contingency scenarios, risk indices are determined that describe the potential impact of each of those scenarios. Contingency scenarios with risk indices are presented visually as graphical representations in the context of a visual representation of the complex network. Analysis of the historical risk indices based on the graphical representations can then provide trends that allow for prediction of future network conditions.

  16. Introduction to Focus Issue: Complex network perspectives on flow systems (United States)

    Donner, Reik V.; Hernández-García, Emilio; Ser-Giacomi, Enrico


    During the last few years, complex network approaches have demonstrated their great potentials as versatile tools for exploring the structural as well as dynamical properties of dynamical systems from a variety of different fields. Among others, recent successful examples include (i) functional (correlation) network approaches to infer hidden statistical interrelationships between macroscopic regions of the human brain or the Earth's climate system, (ii) Lagrangian flow networks allowing to trace dynamically relevant fluid-flow structures in atmosphere, ocean or, more general, the phase space of complex systems, and (iii) time series networks unveiling fundamental organization principles of dynamical systems. In this spirit, complex network approaches have proven useful for data-driven learning of dynamical processes (like those acting within and between sub-components of the Earth's climate system) that are hidden to other analysis techniques. This Focus Issue presents a collection of contributions addressing the description of flows and associated transport processes from the network point of view and its relationship to other approaches which deal with fluid transport and mixing and/or use complex network techniques.

  17. Simulating public private networks as evolving systems

    NARCIS (Netherlands)

    Deljoo, A.; Janssen, M.F.W.H.A.; Klievink, A.J.


    Public-private service networks (PPSN) consist of social and technology components. Development of PPSN is ill-understood as these are dependent on a complex mix of interactions among stakeholders and their technologies and is influenced by contemporary developments. The aim of this paper is to

  18. Networked: The New Social Operating System (United States)

    Rainie, Lee; Wellman, Barry


    Daily life is connected life, its rhythms driven by endless email pings and responses, the chimes and beeps of continually arriving text messages, tweets and retweets, Facebook updates, pictures and videos to post and discuss. Our perpetual connectedness gives us endless opportunities to be part of the give-and-take of networking. Some worry that…

  19. Agricultural information systems and communication networks: the ...

    African Journals Online (AJOL)

    The study examined the Agricultural Information and communication networks among poultry farmers in three (3) area councils of the Federal Capital Territory Abuja, Nigeria. Snow-ball sampling technique was adopted for the study, a total of One hundred and twenty-two (122) respondents were sampled for the study.

  20. Interactivity vs. fairness in networked linux systems

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Wenji; Crawford, Matt; /Fermilab


    In general, the Linux 2.6 scheduler can ensure fairness and provide excellent interactive performance at the same time. However, our experiments and mathematical analysis have shown that the current Linux interactivity mechanism tends to incorrectly categorize non-interactive network applications as interactive, which can lead to serious fairness or starvation issues. In the extreme, a single process can unjustifiably obtain up to 95% of the CPU! The root cause is due to the facts that: (1) network packets arrive at the receiver independently and discretely, and the 'relatively fast' non-interactive network process might frequently sleep to wait for packet arrival. Though each sleep lasts for a very short period of time, the wait-for-packet sleeps occur so frequently that they lead to interactive status for the process. (2) The current Linux interactivity mechanism provides the possibility that a non-interactive network process could receive a high CPU share, and at the same time be incorrectly categorized as 'interactive.' In this paper, we propose and test a possible solution to address the interactivity vs. fairness problems. Experiment results have proved the effectiveness of the proposed solution.

  1. Advanced Medical Technology and Network Systems Research. (United States)


    acceptance and operations of comprehensive radiology networks. Is the PACS cup half full or half empty? SPIE Proc. 1093:194-201 23. Deleted in proof...repeat examination in one to two menstrual cysts approximately 1-2 weeks after menstrual period." Similar recommendations are given for women over

  2. Optimal design of queueing systems for using communication channels with multiple access (United States)

    Sonkin, D. M.; Nazarov, A. A.; Khrul, S. A.; Kudryashova, A. V.


    This article considers the mathematical model of queueing systems for the communication network with multiple access, which is used in the automated group of moving objects control systems. The dynamic communication model in the form of a single-line queuing model with the batch input claims was researched. The method of asymptotic analysis of the communication channel under a heavy load conditions was applied. As a result, the basic probabilistic characteristics of the system were obtained, including: the probability distribution of the waiting time values of the virtual claims, the average length of the queue claims at random time. It has been discovered that the characteristics of the communications models allow performing parametric optimization of communication networks, establishing the most appropriate values of the network parameters.

  3. System of Systems Engineering and Integration Process for Network Transport Assessment (United States)


    through the process to ensure oversight of design and tradeoff decisions for network throughput analyses. 14. SUBJECT TERMS network transport , SoS... Distribution is unlimited. SYSTEM OF SYSTEMS ENGINEERING AND INTEGRATION PROCESS FOR NETWORK TRANSPORT ASSESSMENT Matthew B. Rambo processes to utilize to address network transport design and testing? 2. How can SoS data throughput requirements be identified and

  4. A complex network-based importance measure for mechatronics systems (United States)

    Wang, Yanhui; Bi, Lifeng; Lin, Shuai; Li, Man; Shi, Hao


    In view of the negative impact of functional dependency, this paper attempts to provide an alternative importance measure called Improved-PageRank (IPR) for measuring the importance of components in mechatronics systems. IPR is a meaningful extension of the centrality measures in complex network, which considers usage reliability of components and functional dependency between components to increase importance measures usefulness. Our work makes two important contributions. First, this paper integrates the literature of mechatronic architecture and complex networks theory to define component network. Second, based on the notion of component network, a meaningful IPR is brought into the identifying of important components. In addition, the IPR component importance measures, and an algorithm to perform stochastic ordering of components due to the time-varying nature of usage reliability of components and functional dependency between components, are illustrated with a component network of bogie system that consists of 27 components.

  5. Distributed applications monitoring at system and network level

    CERN Document Server

    Aderholz, Michael; Augé, E; Bagliesi, G; Banistoni, G; Barone, L; Boschini, M; Brunengo, A; Bunn, J J; Butler, J; Campanella, M; Capiluppi, P; D'Amato, M; Darneri, M; Di Mattia, A; Dorokhov, A E; Gagliardi, F; Gaines, I; Gasparini, U; Ghiselli, A; Gordon, J; Grandi, C; Gálvez, P; Harris, F; Holtman, K; Karimäki, V; Karita, Y; Klem, J T; Legrand, I; Leltchouk, M; Linglin, D; Lubrano, P; Luminari, L; McArthur, I C; Michelotto, M; Morita, Y; Nazarenko, A; Newman, H; O'Dell, Vivian; O'Neale, S W; Osculati, B; Pepé, M; Perini, L; Pinfold, James L; Pordes, R; Prelz, F; Putzer, A; Resconi, S; Robertson, L; Rolli, S; Sasaki, T; Sato, H; Schaffer, R D; Schalk, T L; Servoli, L; Sgaravatto, M; Shiers, J; Silvestris, L; Siroli, G P; Sliwa, K; Smith, T; Somigliana, R; Stanescu, C; Stockinger, H E; Ugolotti, D; Valente, E; Vistoli, C; Wilkinson, R P; Willers, Ian Malcolm; Williams, D O


    Most distributed applications are based on architectural models that do not involve real-time knowledge of network status and of their network usage. Moreover the new "network aware" architectures are still under development and their design is not yet complete. We considered, as a use case, an application using ODBMS (Objectivity /DB) for the distributed analysis of experimental data. The dynamic usage of system and network resources at host and application levels has been measured in different client/server configurations, and on several LAN and WAN layouts. The aim was to study the application efficiency and behavior versus the network characteristics and conditions. The most interesting results of the LAN and WAN tests are described. System bottlenecks and limitations have been identified, and efficient working conditions in the different scenarios have been defined. The behavior observed when moving away from the optimal working conditions is also described.

  6. Optimal Planning of Communication System of CPS for Distribution Network

    Directory of Open Access Journals (Sweden)

    Ting Yang


    Full Text Available IoT is the technical basis to realize the CPS (Cyber Physical System for distribution networks, with which the complex system becomes more intelligent and controllable. Because of the multihop and self-organization characteristics, the large-scale heterogeneous CPS network becomes more difficult to plan. Using topological potential theory, one of typical big data analysis technologies, this paper proposed a novel optimal CPS planning model. Topological potential equalization is considered as the optimization objective function in heterogeneous CPS network with the constraints of communication requirements, physical infrastructures, and network reliability. An improved binary particle swarm optimization algorithm is proposed to solve this complex optimal problem. Two IEEE classic examples are adopted in the simulation, and the results show that, compared with benchmark algorithms, our proposed method can provide an effective topology optimization scheme to improve the network reliability and transmitting performance.

  7. A Reference Architecture for Network-Centric Information Systems

    National Research Council Canada - National Science Library

    Renner, Scott; Schaefer, Ronald


    This paper presents the "C2 Enterprise Reference Architecture" (C2ERA), which is a new technical concept of operations for building information systems better suited to the Network-Centric Warfare (NCW) environment...

  8. Air Quality System (AQS) Monitoring Network, EPA OAR OAQPS (United States)

    U.S. Environmental Protection Agency — This GIS dataset contains points which depict air quality monitors within EPA's Air Quality System (AQS) monitoring network. This dataset is updated weekly to...

  9. Robust receding horizon control for networked and distributed nonlinear systems

    CERN Document Server

    Li, Huiping


    This book offers a comprehensive, easy-to-understand overview of receding-horizon control for nonlinear networks. It presents novel general strategies that can simultaneously handle general nonlinear dynamics, system constraints, and disturbances arising in networked and large-scale systems and which can be widely applied. These receding-horizon-control-based strategies can achieve sub-optimal control performance while ensuring closed-loop stability: a feature attractive to engineers. The authors address the problems of networked and distributed control step-by-step, gradually increasing the level of challenge presented. The book first introduces the state-feedback control problems of nonlinear networked systems and then studies output feedback control problems. For large-scale nonlinear systems, disturbance is considered first, then communication delay separately, and lastly the simultaneous combination of delays and disturbances. Each chapter of this easy-to-follow book not only proposes and analyzes novel ...

  10. Integrated Fault Diagnostics of Networks and IT Systems (United States)

    National Aeronautics and Space Administration — The lecture of the Stanford-IVHM lecture series will give an overview of the approaches in building diagnostic solutions for networks and complex systems. The...

  11. The commercial vehicle information systems and networks program, 2013. (United States)


    The Commercial Vehicle Information Systems and Networks (CVISN) grant program supports the Federal Motor Carrier Safety Administrations (FMCSAs) safety mission by providing grant funds to States to: : Improve safety and productivity of moto...

  12. The Commercial Vehicle Information Systems and Network program, 2012. (United States)


    The Commercial Vehicle Information Systems and : Networks (CVISN) program supports that safety : mission by providing grant funds to States for: : Improving safety and productivity of motor : carriers, commercial motor vehicles : (CMVs), and thei...

  13. Cyber-physical system design with sensor networking technologies

    CERN Document Server

    Zeadally, Sherali


    This book describes how wireless sensor networking technologies can help in establishing and maintaining seamless communications between the physical and cyber systems to enable efficient, secure, reliable acquisition, management, and routing of data.

  14. Response of low voltage networks with high penetration of photovoltaic systems to transmission network faults

    NARCIS (Netherlands)

    Skaloumpakas, K.; Boemer, J.C.; Van Ruitenbeek, E.; Gibescu, M.


    The installed capacity of photovoltaic (PV) systems connected to low voltage (LV) networks in Germany has increased to more than 25 GW. Current grid codes still mandate these PV systems to disconnect in case of voltage dips below 0.8 p.u. The resulting response of LV distribution systems with high

  15. Pattern-Oriented Reengineering of a Network System

    Directory of Open Access Journals (Sweden)

    Chung-Horng Lung


    Full Text Available Reengineering is to reorganize and modify existing systems to enhance them or to make them more maintainable. Reengineering is usually necessary as systems evolve due to changes in requirements, technologies, and/or personnel. Design patterns capture recurring structures and dynamics among software participants to facilitate reuse of successful designs. Design patterns are common and well studied in network systems. In this project, we reengineer part of a network system with some design patterns to support future evolution and performance improvement. We start with reverse engineering effort to understand the system and recover its high level architecture. Then we apply concurrent and networked design patterns to restructure the main sub-system. Those patterns include Half-Sync/Half-Async, Monitor Object, and Scoped Locking idiom. The resulting system is more maintainable and has better performance.

  16. Spacecraft Neural Network Control System Design using FPGA


    Hanaa T. El-Madany; Faten H. Fahmy; Ninet M. A. El-Rahman; Hassen T. Dorrah


    Designing and implementing intelligent systems has become a crucial factor for the innovation and development of better products of space technologies. A neural network is a parallel system, capable of resolving paradigms that linear computing cannot. Field programmable gate array (FPGA) is a digital device that owns reprogrammable properties and robust flexibility. For the neural network based instrument prototype in real time application, conventional specific VLSI neural chip design suffer...

  17. Summer School Mathematical Foundations of Complex Networked Information Systems

    CERN Document Server

    Fosson, Sophie; Ravazzi, Chiara


    Introducing the reader to the mathematics beyond complex networked systems, these lecture notes investigate graph theory, graphical models, and methods from statistical physics. Complex networked systems play a fundamental role in our society, both in everyday life and in scientific research, with applications ranging from physics and biology to economics and finance. The book is self-contained, and requires only an undergraduate mathematical background.

  18. Monitoring water distribution systems: understanding and managing sensor networks


    Ediriweera, D. D.; Marshall, I. W.


    Sensor networks are currently being trialed by the water distribution industry for monitoring complex distribution infrastructure. The paper presents an investigation in to the architecture and performance of a sensor system deployed for monitoring such a distribution network. The study reveals lapses in systems design and management, resulting in a fifth of the data being either missing or erroneous. Findings identify the importance of undertaking in-depth consideration of all aspects of a l...

  19. Optical production systems using neural networks and symbolic substitution (United States)

    Botha, Elizabeth; Casasent, David; Barnard, Etienne


    Two optical implementations of production systems are advanced. The production systems operate on a knowledge base where facts and rules are encoded as formulas in propositional calculus. The first implementation is a binary neural network. An analog neural network is used to include reasoning with uncertainties. The second implementation uses a new optical symbolic substitution correlator. This implementation is useful when a set of similar situations has to be handled in parallel on one processor.

  20. Robust Filtering for Networked Stochastic Systems Subject to Sensor Nonlinearity

    Directory of Open Access Journals (Sweden)

    Guoqiang Wu


    Full Text Available The problem of network-based robust filtering for stochastic systems with sensor nonlinearity is investigated in this paper. In the network environment, the effects of the sensor saturation, output quantization, and network-induced delay are taken into simultaneous consideration, and the output measurements received in the filter side are incomplete. The random delays are modeled as a linear function of the stochastic variable described by a Bernoulli random binary distribution. The derived criteria for performance analysis of the filtering-error system and filter design are proposed which can be solved by using convex optimization method. Numerical examples show the effectiveness of the design method.

  1. A local area computer network expert system framework (United States)

    Dominy, Robert


    Over the past years an expert system called LANES designed to detect and isolate faults in the Goddard-wide Hybrid Local Area Computer Network (LACN) was developed. As a result, the need for developing a more generic LACN fault isolation expert system has become apparent. An object oriented approach was explored to create a set of generic classes, objects, rules, and methods that would be necessary to meet this need. The object classes provide a convenient mechanism for separating high level information from low level network specific information. This approach yeilds a framework which can be applied to different network configurations and be easily expanded to meet new needs.

  2. Systems and methods for modeling and analyzing networks (United States)

    Hill, Colin C; Church, Bruce W; McDonagh, Paul D; Khalil, Iya G; Neyarapally, Thomas A; Pitluk, Zachary W


    The systems and methods described herein utilize a probabilistic modeling framework for reverse engineering an ensemble of causal models, from data and then forward simulating the ensemble of models to analyze and predict the behavior of the network. In certain embodiments, the systems and methods described herein include data-driven techniques for developing causal models for biological networks. Causal network models include computational representations of the causal relationships between independent variables such as a compound of interest and dependent variables such as measured DNA alterations, changes in mRNA, protein, and metabolites to phenotypic readouts of efficacy and toxicity.

  3. Analysis and implementation of packet preemption for Time Sensitive Networks

    DEFF Research Database (Denmark)

    Zhou, Zifan; Yan, Ying; Ruepp, Sarah Renée


    A standard priority-queuing system is capable of arranging packets with different traffic classes to guarantee a relatively low latency for the high priority traffic. However, in practical cases, severe delay may be caused by starting a large, low-priority frame ahead of a time-critical frame....... In this paper, interspersed express traffic is evaluated, which enables preemption of non-time-critical transmission, in particular, the preemptive queuing system allows the cut-through transmission for critical traffic and minimizes the jitter. We analyse the performance of packet preemption through a system...

  4. System for testing properties of a network (United States)

    Rawle, Michael; Bartholomew, David B.; Soares, Marshall A.


    A method for identifying properties of a downhole electromagnetic network in a downhole tool sting, including the step of providing an electromagnetic path intermediate a first location and a second location on the electromagnetic network. The method further includes the step of providing a receiver at the second location. The receiver includes a known reference. The analog signal includes a set amplitude, a set range of frequencies, and a set rate of change between the frequencies. The method further includes the steps of sending the analog signal, and passively modifying the signal. The analog signal is sent from the first location through the electromagnetic path, and the signal is modified by the properties of the electromagnetic path. The method further includes the step of receiving a modified signal at the second location and comparing the known reference to the modified signal.

  5. The Casualty Network System Capstone Project (United States)


    External Defibrillator AF – Assault Force ARS – Acute Radiation Sickness CBRN – Chemical, Biological, Radiological and Nuclear CNS – Casualty...elements and their roles. ................... 28   xiv THIS PAGE INTENTIONALLY LEFT BLANK xv LIST OF ACRONYMS AND ABBREVIATIONS AED – Automatic ...that the casualty is automatically placed one degree further than the medic from the network. This occurs because even if the casualty is the most

  6. Network Analysis and Modeling in Systems Biology


    Bosque Chacón, Gabriel


    This thesis is dedicated to the study and comprehension of biological networks at the molecular level. The objectives were to analyse their topology, integrate it in a genotype-phenotype analysis, develop richer mathematical descriptions for them, study their community structure and compare different methodologies for estimating their internal fluxes. The work presented in this document moves around three main axes. The first one is the biological. Which organisms were studied in this ...

  7. Social Insects: A Model System for Network Dynamics (United States)

    Charbonneau, Daniel; Blonder, Benjamin; Dornhaus, Anna

    Social insect colonies (ants, bees, wasps, and termites) show sophisticated collective problem-solving in the face of variable constraints. Individuals exchange information and materials such as food. The resulting network structure and dynamics can inform us about the mechanisms by which the insects achieve particular collective behaviors and these can be transposed to man-made and social networks. We discuss how network analysis can answer important questions about social insects, such as how effective task allocation or information flow is realized. We put forward the idea that network analysis methods are under-utilized in social insect research, and that they can provide novel ways to view the complexity of collective behavior, particularly if network dynamics are taken into account. To illustrate this, we present an example of network tasks performed by ant workers, linked by instances of workers switching from one task to another. We show how temporal network analysis can propose and test new hypotheses on mechanisms of task allocation, and how adding temporal elements to static networks can drastically change results. We discuss the benefits of using social insects as models for complex systems in general. There are multiple opportunities emergent technologies and analysis methods in facilitating research on social insect network. The potential for interdisciplinary work could significantly advance diverse fields such as behavioral ecology, computer sciences, and engineering.

  8. System-Level Design Methodologies for Networked Multiprocessor Systems-on-Chip

    DEFF Research Database (Denmark)

    Virk, Kashif Munir


    is the first such attempt in the published literature. The second part of the thesis deals with the issues related to the development of system-level design methodologies for networked multiprocessor systems-on-chip at various levels of design abstraction with special focus on the modeling and design...... of wireless integrated sensor networks which are an emerging class of networked embedded computer systems. The work described here demonstrates how to model multiprocessor systems-on-chip at the system level by abstracting away most of the lower-level details albeit retaining the parameters most relevant...... at the system-level. The multiprocessor modeling framework is then extended to include models of networked multiprocessor systems-on-chip which is then employed to model wireless sensor networks both at the sensor node level as well as the wireless network level. In the third and the final part, the thesis...

  9. Architectural transformations in network services and distributed systems

    CERN Document Server

    Luntovskyy, Andriy


    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, ...

  10. Dynamics of slow and fast systems on complex networks

    Indian Academy of Sciences (India)

    .35(green), 0.5(blue). Region 2, where = 0 corre- sponds to AD. are coupled to form the network, the emergent frequency may depend also on the number of slow systems m. ... slow (red) systems, while fast (green) systems show large.

  11. Implementation of an Adaptive Learning System Using a Bayesian Network (United States)

    Yasuda, Keiji; Kawashima, Hiroyuki; Hata, Yoko; Kimura, Hiroaki


    An adaptive learning system is proposed that incorporates a Bayesian network to efficiently gauge learners' understanding at the course-unit level. Also, learners receive content that is adapted to their measured level of understanding. The system works on an iPad via the Edmodo platform. A field experiment using the system in an elementary school…

  12. Double-hop networks using VSATs for the Intelsat system (United States)

    Mizuno, Toshio; Nohara, Mitsuo; Watanabe, Fumio; Takeuchi, Yoshio; Honda, Teruhiko

    The double-hop VSAT (very small aperture terminal) network was studied with emphasis on its feasibility and networking in the Intelsat system. The results of channel-capacity estimation indicate that reasonable channel capacity and availability objectives equal to those for Super IBS (Intelsat business services) are attainable through the use of the uplink and downlink power control incorporated in the outbound link with BPSK/SCPC (binary-phase shift keying/single channel per carrier) transmission. Possible network architectures for various beam configurations were devised, and the accessibility of individual network architectures was analyzed in terms of blocking probability and call setup time. Based on the results of architecture study, an example implementation of VSAT system is shown. Furthermore, experimental results on the developed VSAT system are discussed. The experiment showed that the transmit power control for the outbound SCPC carrier is conducive to meeting stringent performance objectives stipulated for international digital transmissions.

  13. Network-based reading system for lung cancer screening CT (United States)

    Fujino, Yuichi; Fujimura, Kaori; Nomura, Shin-ichiro; Kawashima, Harumi; Tsuchikawa, Megumu; Matsumoto, Toru; Nagao, Kei-ichi; Uruma, Takahiro; Yamamoto, Shinji; Takizawa, Hotaka; Kuroda, Chikazumi; Nakayama, Tomio


    This research aims to support chest computed tomography (CT) medical checkups to decrease the death rate by lung cancer. We have developed a remote cooperative reading system for lung cancer screening over the Internet, a secure transmission function, and a cooperative reading environment. It is called the Network-based Reading System. A telemedicine system involves many issues, such as network costs and data security if we use it over the Internet, which is an open network. In Japan, broadband access is widespread and its cost is the lowest in the world. We developed our system considering human machine interface and security. It consists of data entry terminals, a database server, a computer aided diagnosis (CAD) system, and some reading terminals. It uses a secure Digital Imaging and Communication in Medicine (DICOM) encrypting method and Public Key Infrastructure (PKI) based secure DICOM image data distribution. We carried out an experimental trial over the Japan Gigabit Network (JGN), which is the testbed for the Japanese next-generation network, and conducted verification experiments of secure screening image distribution, some kinds of data addition, and remote cooperative reading. We found that network bandwidth of about 1.5 Mbps enabled distribution of screening images and cooperative reading and that the encryption and image distribution methods we proposed were applicable to the encryption and distribution of general DICOM images via the Internet.

  14. Optical interconnection networks for high-performance computing systems. (United States)

    Biberman, Aleksandr; Bergman, Keren


    Enabled by silicon photonic technology, optical interconnection networks have the potential to be a key disruptive technology in computing and communication industries. The enduring pursuit of performance gains in computing, combined with stringent power constraints, has fostered the ever-growing computational parallelism associated with chip multiprocessors, memory systems, high-performance computing systems and data centers. Sustaining these parallelism growths introduces unique challenges for on- and off-chip communications, shifting the focus toward novel and fundamentally different communication approaches. Chip-scale photonic interconnection networks, enabled by high-performance silicon photonic devices, offer unprecedented bandwidth scalability with reduced power consumption. We demonstrate that the silicon photonic platforms have already produced all the high-performance photonic devices required to realize these types of networks. Through extensive empirical characterization in much of our work, we demonstrate such feasibility of waveguides, modulators, switches and photodetectors. We also demonstrate systems that simultaneously combine many functionalities to achieve more complex building blocks. We propose novel silicon photonic devices, subsystems, network topologies and architectures to enable unprecedented performance of these photonic interconnection networks. Furthermore, the advantages of photonic interconnection networks extend far beyond the chip, offering advanced communication environments for memory systems, high-performance computing systems, and data centers.

  15. Analog neural network-based helicopter gearbox health monitoring system. (United States)

    Monsen, P T; Dzwonczyk, M; Manolakos, E S


    The development of a reliable helicopter gearbox health monitoring system (HMS) has been the subject of considerable research over the past 15 years. The deployment of such a system could lead to a significant saving in lives and vehicles as well as dramatically reduce the cost of helicopter maintenance. Recent research results indicate that a neural network-based system could provide a viable solution to the problem. This paper presents two neural network-based realizations of an HMS system. A hybrid (digital/analog) neural system is proposed as an extremely accurate off-line monitoring tool used to reduce helicopter gearbox maintenance costs. In addition, an all analog neural network is proposed as a real-time helicopter gearbox fault monitor that can exploit the ability of an analog neural network to directly compute the discrete Fourier transform (DFT) as a sum of weighted samples. Hardware performance results are obtained using the Integrated Neural Computing Architecture (INCA/1) analog neural network platform that was designed and developed at The Charles Stark Draper Laboratory. The results indicate that it is possible to achieve a 100% fault detection rate with 0% false alarm rate by performing a DFT directly on the first layer of INCA/1 followed by a small-size two-layer feed-forward neural network and a simple post-processing majority voting stage.

  16. Active system area networks for data intensive computations. Final report

    Energy Technology Data Exchange (ETDEWEB)



    The goal of the Active System Area Networks (ASAN) project is to develop hardware and software technologies for the implementation of active system area networks (ASANs). The use of the term ''active'' refers to the ability of the network interfaces to perform application-specific as well as system level computations in addition to their traditional role of data transfer. This project adopts the view that the network infrastructure should be an active computational entity capable of supporting certain classes of computations that would otherwise be performed on the host CPUs. The result is a unique network-wide programming model where computations are dynamically placed within the host CPUs or the NIs depending upon the quality of service demands and network/CPU resource availability. The projects seeks to demonstrate that such an approach is a better match for data intensive network-based applications and that the advent of low-cost powerful embedded processors and configurable hardware makes such an approach economically viable and desirable.

  17. Small-network approximations for geometrically frustrated Ising systems. (United States)

    Zhuang, Bilin; Lannert, Courtney


    The study of frustrated spin systems often requires time-consuming numerical simulations. As the simplest approach, the classical Ising model is often used to investigate the thermodynamic behavior of such systems. Exploiting the small correlation lengths in frustrated Ising systems, we develop a method for obtaining first approximations to the energetic properties of frustrated two-dimensional Ising systems using small networks of less than 30 spins. These small networks allow much faster numerical simulations, and more importantly, analytical evaluations of their properties are numerically tractable. We choose Ising systems on the triangular lattice, the kagome lattice, and the triangular kagome lattice as prototype systems and find small systems that can serve as good approximations to these prototype systems. Through comparisons between the properties of extended models and small systems, we develop a set of criteria for constructing small networks to approximate general infinite two-dimensional frustrated Ising systems. This method of using small networks provides a different and efficient way to obtain a first approximation to the properties of frustrated spin systems.

  18. Reliability issues of free-space communications systems and networks (United States)

    Willebrand, Heinz A.


    Free space optics (FSO) is a high-speed point-to-point connectivity solution traditionally used in the enterprise campus networking market for building-to-building LAN connectivity. However, more recently some wire line and wireless carriers started to deploy FSO systems in their networks. The requirements on FSO system reliability, meaing both system availability and component reliability, are far more stringent in the carrier market when compared to the requirements in the enterprise market segment. This paper tries to outline some of the aspects that are important to ensure carrier class system reliability.

  19. Bluetooth Roaming for Sensor Network System in Clinical Environment. (United States)

    Kuroda, Tomohiro; Noma, Haruo; Takase, Kazuhiko; Sasaki, Shigeto; Takemura, Tadamasa


    A sensor network is key infrastructure for advancing a hospital information system (HIS). The authors proposed a method to provide roaming functionality for Bluetooth to realize a Bluetooth-based sensor network, which is suitable to connect clinical devices. The proposed method makes the average response time of a Bluetooth connection less than one second by making the master device repeat the inquiry process endlessly and modifies parameters of the inquiry process. The authors applied the developed sensor network for daily clinical activities in an university hospital, and confirmed the stabilitya and effectiveness of the sensor network. As Bluetooth becomes a quite common wireless interface for medical devices, the proposed protocol that realizes Bluetooth-based sensor network enables HIS to equip various clinical devices and, consequently, lets information and communication technologies advance clinical services.

  20. Securing Communication in Ambient Networks for Speech Therapy Systems

    Directory of Open Access Journals (Sweden)

    ZAHARIA, M. H.


    Full Text Available One of the most present issues of computer wireless networks is the security. Comparing with their wired counterpart, the wireless networks not only accentuate some of the well-known security vulnerabilities but they are subject of new and specific ones. Among the existing wireless networks the ad hoc ones are the most exposed to attacks and collusions due to the absence of any centralized control. The most efficient way to ensure the communication secrecy, inclusively for ad hoc wireless networks, is the cryptography. From many reasons, following from specific operating conditions, the employment of asymmetric key techniques and Public Key Infrastructure is not a realistic choice. In the networks with a large number of nodes, as wireless sensor networks, a large number of secret keys are involved in order to ensure the communication secrecy. While dynamicity is one of the essential features of mobile wireless networks, when nodes may leave or join the network and in the absence of a centralized control entity, the management of secret keys is crucial. The paper presents the main aspects of mobile wireless networks security and focuses on the key management issue in ad-hoc wireless networks.In this paper the problem of securing mobile devices used in ambient networks for speech therapy is presented. The main target consists in making various mobile devices involved in speech therapy to maintain both the confidentiality of personal data of the patient and also to avoid interference when simultaneous communicate with the control center. Due to non-technical type of user all password management will be made automatic by the control system. As result the mobile device will have a user transparent security layer added. The problem of people from isolated community treatment is also solved by this approach.

  1. Multiple neural network approaches to clinical expert systems (United States)

    Stubbs, Derek F.


    We briefly review the concept of computer aided medical diagnosis and more extensively review the the existing literature on neural network applications in the field. Neural networks can function as simple expert systems for diagnosis or prognosis. Using a public database we develop a neural network for the diagnosis of a major presenting symptom while discussing the development process and possible approaches. MEDICAL EXPERTS SYSTEMS COMPUTER AIDED DIAGNOSIS Biomedicine is an incredibly diverse and multidisciplinary field and it is not surprising that neural networks with their many applications are finding more and more applications in the highly non-linear field of biomedicine. I want to concentrate on neural networks as medical expert systems for clinical diagnosis or prognosis. Expert Systems started out as a set of computerized " ifthen" rules. Everything was reduced to boolean logic and the promised land of computer experts was said to be in sight. It never came. Why? First the computer code explodes as the number of " ifs" increases. All the " ifs" have to interact. Second experts are not very good at reducing expertise to language. It turns out that experts recognize patterns and have non-verbal left-brain intuition decision processes. Third learning by example rather than learning by rule is the way natural brains works and making computers work by rule-learning is hideously labor intensive. Neural networks can learn from example. They learn the results

  2. Pattern reverberation in networks of excitable systems with connection delays (United States)

    Lücken, Leonhard; Rosin, David P.; Worlitzer, Vasco M.; Yanchuk, Serhiy


    We consider the recurrent pulse-coupled networks of excitable elements with delayed connections, which are inspired by the biological neural networks. If the delays are tuned appropriately, the network can either stay in the steady resting state, or alternatively, exhibit a desired spiking pattern. It is shown that such a network can be used as a pattern-recognition system. More specifically, the application of the correct pattern as an external input to the network leads to a self-sustained reverberation of the encoded pattern. In terms of the coupling structure, the tolerance and the refractory time of the individual systems, we determine the conditions for the uniqueness of the sustained activity, i.e., for the functionality of the network as an unambiguous pattern detector. We point out the relation of the considered systems with cyclic polychronous groups and show how the assumed delay configurations may arise in a self-organized manner when a spike-time dependent plasticity of the connection delays is assumed. As excitable elements, we employ the simplistic coincidence detector models as well as the Hodgkin-Huxley neuron models. Moreover, the system is implemented experimentally on a Field-Programmable Gate Array.

  3. A breathing circuit alarm system based on neural networks. (United States)

    Orr, J A; Westenskow, D R


    The objectives of our study were (1) to implement intelligent respiratory alarms with a neural network; and (2) to increase alarm specificity and decrease false-alarm rates compared with current alarms. We trained a neural network to recognize 13 faults in an anesthesia breathing circuit. The system extracted 30 breath-to-breath features from the airway CO2, flow, and pressure signals. We created training data for the network by introducing 13 faults repeatedly in 5 dogs (616 total faults). We used the data to train the neural network using the backward error propagation algorithm. In animals, the trained network reported the alarms correctly for 95.0% of the faults when tested during controlled ventilation, and for 86.9% of the faults during spontaneous breathing. When tested in the operating room, the system found and correctly reported 54 of 57 faults that occurred during 43.6 hr of use. The alarm system produced a total of 74 false alarms during 43.6 hr of monitoring. Neural networks may be useful in creating intelligent anesthesia alarm systems.

  4. Network structure classification and features of water distribution systems (United States)

    Giustolisi, Orazio; Simone, Antonietta; Ridolfi, Luca


    The network connectivity structure of water distribution systems (WDSs) represents the domain where hydraulic processes occur, driving the emerging behavior of such systems, for example with respect to robustness and vulnerability. In complex network theory (CNT), a common way of classifying the network structure and connectivity is the association of the nodal degree distribution to specific probability distribution models, and during the last decades, researchers classified many real networks using the Poisson or Pareto distributions. In spite of the fact that degree-based network classification could play a crucial role to assess WDS vulnerability, this task is not easy because the network structure of WDSs is strongly constrained by spatial characteristics of the environment where they are constructed. The consequence of these spatial constraints is that the nodal degree spans very small ranges in WDSs hindering a reliable classification by the standard approach based on the nodal degree distribution. This work investigates the classification of the network structure of 22 real WDSs, built in different environments, demonstrating that the Poisson distribution generally models the degree distributions very well. In order to overcome the problem of the reliable classification based on the standard nodal degree, we define the "neighborhood" degree, equal to the sum of the nodal degrees of the nearest topological neighbors (i.e., the adjacent nodes). This definition of "neighborhood" degree is consistent with the fact that the degree of a single node is not significant for analysis of WDSs.

  5. Stochastic S-system modeling of gene regulatory network. (United States)

    Chowdhury, Ahsan Raja; Chetty, Madhu; Evans, Rob


    Microarray gene expression data can provide insights into biological processes at a system-wide level and is commonly used for reverse engineering gene regulatory networks (GRN). Due to the amalgamation of noise from different sources, microarray expression profiles become inherently noisy leading to significant impact on the GRN reconstruction process. Microarray replicates (both biological and technical), generated to increase the reliability of data obtained under noisy conditions, have limited influence in enhancing the accuracy of reconstruction . Therefore, instead of the conventional GRN modeling approaches which are deterministic, stochastic techniques are becoming increasingly necessary for inferring GRN from noisy microarray data. In this paper, we propose a new stochastic GRN model by investigating incorporation of various standard noise measurements in the deterministic S-system model. Experimental evaluations performed for varying sizes of synthetic network, representing different stochastic processes, demonstrate the effect of noise on the accuracy of genetic network modeling and the significance of stochastic modeling for GRN reconstruction . The proposed stochastic model is subsequently applied to infer the regulations among genes in two real life networks: (1) the well-studied IRMA network, a real-life in-vivo synthetic network constructed within the Saccharomyces cerevisiae yeast, and (2) the SOS DNA repair network in Escherichia coli.

  6. Exact tensor network ansatz for strongly interacting systems (United States)

    Zaletel, Michael P.

    It appears that the tensor network ansatz, while not quite complete, is an efficient coordinate system for the tiny subset of a many-body Hilbert space which can be realized as a low energy state of a local Hamiltonian. However, we don't fully understand precisely which phases are captured by the tensor network ansatz, how to compute their physical observables (even numerically), or how to compute a tensor network representation for a ground state given a microscopic Hamiltonian. These questions are algorithmic in nature, but their resolution is intimately related to understanding the nature of quantum entanglement in many-body systems. For this reason it is useful to compute the tensor network representation of various `model' wavefunctions representative of different phases of matter; this allows us to understand how the entanglement properties of each phase are expressed in the tensor network ansatz, and can serve as test cases for algorithm development. Condensed matter physics has many illuminating model wavefunctions, such as Laughlin's celebrated wave function for the fractional quantum Hall effect, the Bardeen-Cooper-Schrieffer wave function for superconductivity, and Anderson's resonating valence bond ansatz for spin liquids. This thesis presents some results on exact tensor network representations of these model wavefunctions. In addition, a tensor network representation is given for the time evolution operator of a long-range one-dimensional Hamiltonian, which allows one to numerically simulate the time evolution of power-law interacting spin chains as well as two-dimensional strips and cylinders.

  7. Optimal Sensor Networks Scheduling in Identification of Distributed Parameter Systems

    CERN Document Server

    Patan, Maciej


    Sensor networks have recently come into prominence because they hold the potential to revolutionize a wide spectrum of both civilian and military applications. An ingenious characteristic of sensor networks is the distributed nature of data acquisition. Therefore they seem to be ideally prepared for the task of monitoring processes with spatio-temporal dynamics which constitute one of most general and important classes of systems in modelling of the real-world phenomena. It is clear that careful deployment and activation of sensor nodes are critical for collecting the most valuable information from the observed environment. Optimal Sensor Network Scheduling in Identification of Distributed Parameter Systems discusses the characteristic features of the sensor scheduling problem, analyzes classical and recent approaches, and proposes a wide range of original solutions, especially dedicated for networks with mobile and scanning nodes. Both researchers and practitioners will find the case studies, the proposed al...

  8. Mathematical Analysis of a PDE System for Biological Network Formation

    KAUST Repository

    Haskovec, Jan


    Motivated by recent physics papers describing rules for natural network formation, we study an elliptic-parabolic system of partial differential equations proposed by Hu and Cai [13, 15]. The model describes the pressure field thanks to Darcy\\'s type equation and the dynamics of the conductance network under pressure force effects with a diffusion rate D >= 0 representing randomness in the material structure. We prove the existence of global weak solutions and of local mild solutions and study their long term behavior. It turns out that, by energy dissipation, steady states play a central role to understand the network formation capacity of the system. We show that for a large diffusion coefficient D, the zero steady state is stable, while network formation occurs for small values of D due to the instability of the zero steady state, and the borderline case D = 0 exhibits a large class of dynamically stable (in the linearized sense) steady states.

  9. System Identification, Prediction, Simulation and Control with Neural Networks

    DEFF Research Database (Denmark)

    Sørensen, O.


    a Gauss-Newton search direction is applied. 3) Amongst numerous model types, often met in control applications, only the Non-linear ARMAX (NARMAX) model, representing input/output description, is examined. A simulated example confirms that a neural network has the potential to perform excellent System...... Identification, Prediction, Simulation and Control of a dynamic, non-linear and noisy process. Further, the difficulties to control a practical non-linear laboratory process in a satisfactory way by using a traditional controller are overcomed by using a trained neural network to perform non-linear System......The intention of this paper is to make a systematic examination of the possibilities of applying neural networks in those technical areas, which are familiar to a control engineer. In other words, the potential of neural networks in control applications is given higher priority than a detailed...


    Villarreal, J.


    The primary purpose of NNETS (Neural Network Environment on a Transputer System) is to provide users a high degree of flexibility in creating and manipulating a wide variety of neural network topologies at processing speeds not found in conventional computing environments. To accomplish this purpose, NNETS supports back propagation and back propagation related algorithms. The back propagation algorithm used is an implementation of Rumelhart's Generalized Delta Rule. NNETS was developed on the INMOS Transputer. NNETS predefines a Back Propagation Network, a Jordan Network, and a Reinforcement Network to assist users in learning and defining their own networks. The program also allows users to configure other neural network paradigms from the NNETS basic architecture. The Jordan network is basically a feed forward network that has the outputs connected to a pseudo input layer. The state of the network is dependent on the inputs from the environment plus the state of the network. The Reinforcement network learns via a scalar feedback signal called reinforcement. The network propagates forward randomly. The environment looks at the outputs of the network to produce a reinforcement signal that is fed back to the network. NNETS was written for the INMOS C compiler D711B version 1.3 or later (MS-DOS version). A small portion of the software was written in the OCCAM language to perform the communications routing between processors. NNETS is configured to operate on a 4 X 10 array of Transputers in sequence with a Transputer based graphics processor controlled by a master IBM PC 286 (or better) Transputer. A RGB monitor is required which must be capable of 512 X 512 resolution. It must be able to receive red, green, and blue signals via BNC connectors. NNETS is meant for experienced Transputer users only. The program is distributed on 5.25 inch 1.2Mb MS-DOS format diskettes. NNETS was developed in 1991. Transputer and OCCAM are registered trademarks of Inmos Corporation. MS

  11. Neuromorphic computing applications for network intrusion detection systems (United States)

    Garcia, Raymond C.; Pino, Robinson E.


    What is presented here is a sequence of evolving concepts for network intrusion detection. These concepts start with neuromorphic structures for XOR-based signature matching and conclude with computationally based network intrusion detection system with an autonomous structuring algorithm. There is evidence that neuromorphic computation for network intrusion detection is fractal in nature under certain conditions. Specifically, the neural structure can take fractal form when simple neural structuring is autonomous. A neural structure is fractal by definition when its fractal dimension exceeds the synaptic matrix dimension. The authors introduce the use of fractal dimension of the neuromorphic structure as a factor in the autonomous restructuring feedback loop.

  12. FIPA agent based network distributed control system

    Energy Technology Data Exchange (ETDEWEB)

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


    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.

  13. An Intelligent Handover Management System for Future Generation Wireless Networks


    Kassar Meriem; Kervella Brigitte; Pujolle Guy


    Abstract Future generation wireless networks should provide to mobile users the best connectivity to services anywhere at anytime. The most challenging problem is the seamless intersystem/vertical mobility across heterogeneous wireless networks. In order to answer it, a vertical handover management system is needed. In our paper, we propose an intelligent solution answering user requirements and ensuring service continuity. We focus on a vertical handover decision strategy based on the contex...

  14. Research on networked manufacturing system for reciprocating pump industry (United States)

    Wu, Yangdong; Qi, Guoning; Xie, Qingsheng; Lu, Yujun


    Networked manufacturing is a trend of reciprocating pump industry. According to the enterprises' requirement, the architecture of networked manufacturing system for reciprocating pump industry was proposed, which composed of infrastructure layer, system management layer, application service layer and user layer. Its main functions included product data management, ASP service, business management, and customer relationship management, its physics framework was a multi-tier internet-based model; the concept of ASP service integration was put forward and its process model was also established. As a result, a networked manufacturing system aimed at the characteristics of reciprocating pump industry was built. By implementing this system, reciprocating pump industry can obtain a new way to fully utilize their own resources and enhance the capabilities to respond to the global market quickly.

  15. Applying New Network Security Technologies to SCADA Systems.

    Energy Technology Data Exchange (ETDEWEB)

    Hurd, Steven A; Stamp, Jason Edwin; Duggan, David P; Chavez, Adrian R.


    Supervisory Control and Data Acquisition (SCADA) systems for automation are very important for critical infrastructure and manufacturing operations. They have been implemented to work in a number of physical environments using a variety of hardware, software, networking protocols, and communications technologies, often before security issues became of paramount concern. To offer solutions to security shortcomings in the short/medium term, this project was to identify technologies used to secure "traditional" IT networks and systems, and then assess their efficacy with respect to SCADA systems. These proposed solutions must be relatively simple to implement, reliable, and acceptable to SCADA owners and operators. 4This page intentionally left blank.

  16. Dynamical Systems Theory for Transparent Symbolic Computation in Neuronal Networks


    Carmantini, Giovanni Sirio


    In this thesis, we explore the interface between symbolic and dynamical system computation, with particular regard to dynamical system models of neuronal networks. In doing so, we adhere to a definition of computation as the physical realization of a formal system, where we say that a dynamical system performs a computation if a correspondence can be found between its dynamics on a vectorial space and the formal system’s dynamics on a symbolic space. Guided by this definition, we characterize...

  17. Secure Data Network System (SDNS) network, transport, and message security protocols (United States)

    Dinkel, C.


    The Secure Data Network System (SDNS) project, implements computer to computer communications security for distributed applications. The internationally accepted Open Systems Interconnection (OSI) computer networking architecture provides the framework for SDNS. SDNS uses the layering principles of OSI to implement secure data transfers between computer nodes of local area and wide area networks. Four security protocol documents developed by the National Security Agency (NSA) as output from the SDNS project are included. SDN.301 provides the framework for security at layer 3 of the OSI Model. Cryptographic techniques to provide data protection for transport connections or for connectionless-mode transmission are described in SDN.401. Specifications for message security service and protocol are contained in SDN.701. Directory System Specifications for Message Security Protocol are covered in SDN.702.

  18. Neural Network Based Intrusion Detection System for Critical Infrastructures

    Energy Technology Data Exchange (ETDEWEB)

    Todd Vollmer; Ondrej Linda; Milos Manic


    Resiliency and security in control systems such as SCADA and Nuclear plant’s in today’s world of hackers and malware are a relevant concern. Computer systems used within critical infrastructures to control physical functions are not immune to the threat of cyber attacks and may be potentially vulnerable. Tailoring an intrusion detection system to the specifics of critical infrastructures can significantly improve the security of such systems. The IDS-NNM – Intrusion Detection System using Neural Network based Modeling, is presented in this paper. The main contributions of this work are: 1) the use and analyses of real network data (data recorded from an existing critical infrastructure); 2) the development of a specific window based feature extraction technique; 3) the construction of training dataset using randomly generated intrusion vectors; 4) the use of a combination of two neural network learning algorithms – the Error-Back Propagation and Levenberg-Marquardt, for normal behavior modeling. The presented algorithm was evaluated on previously unseen network data. The IDS-NNM algorithm proved to be capable of capturing all intrusion attempts presented in the network communication while not generating any false alerts.

  19. Network characteristics emerging from agent interactions in balanced distributed system. (United States)

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


    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.

  20. Revisiting Anomaly-based Network Intrusion Detection Systems

    NARCIS (Netherlands)

    Bolzoni, D.


    Intrusion detection systems (IDSs) are well-known and widely-deployed security tools to detect cyber-attacks and malicious activities in computer systems and networks. A signature-based IDS works similar to anti-virus software. It employs a signature database of known attacks, and a successful match

  1. Specification Mining for Intrusion Detection in Networked Control Systems

    NARCIS (Netherlands)

    Caselli, M.; Zambon, Emmanuele; Amann, Johanna; Sommer, Robin; Kargl, Frank


    This paper discusses a novel approach to specification-based intrusion detection in the field of networked control systems. Our approach reduces the substantial human effort required to deploy a specification-based intrusion detection system by automating the development of its specification rules.

  2. Role of neural network models for developing speech systems

    Indian Academy of Sciences (India)

    These prosody models are further examined for applications such as text to speech synthesis, speech recognition, speaker recognition and language identification. Neural network models in voice conversion system are explored for capturing the mapping functions between source and target speakers at source, system and ...

  3. NNSYSID - toolbox for system identification with neural networks

    DEFF Research Database (Denmark)

    Norgaard, M.; Ravn, Ole; Poulsen, Niels Kjølstad


    The NNSYSID toolset for System Identification has been developed as an add on to MATLAB(R). The NNSYSID toolbox has been designed to assist identification of nonlinear dynamic systems. It contains a number of nonlinear model structures based on neural networks, effective training algorithms...

  4. Systems chemistry: logic gates, arithmetic units, and network motifs in small networks. (United States)

    Wagner, Nathaniel; Ashkenasy, Gonen


    A mixture of molecules can be regarded as a network if all the molecular components participate in some kind of interaction with other molecules--either physical or functional interactions. Template-assisted ligation reactions that direct replication processes can serve as the functional elements that connect two members of a chemical network. In such a process, the template does not necessarily catalyze its own formation, but rather the formation of another molecule, which in turn can operate as a template for reactions within the network medium. It was postulated that even networks made up of small numbers of molecules possess a wealth of molecular information sufficient to perform rather complex behavior. To probe this assumption, we have constructed virtual arrays consisting of three replicating molecules, in which dimer templates are capable of catalyzing reactants to form additional templates. By using realistic parameters from peptides or DNA replication experiments, we simulate the construction of various functional motifs within the networks. Specifically, we have designed and implemented each of the three-element Boolean logic gates, and show how these networks are assembled from four basic "building blocks". We also show how the catalytic pathways can be wired together to perform more complex arithmetic units and network motifs, such as the half adder and half subtractor computational modules, and the coherent feed-forward loop network motifs under different sets of parameters. As in previous studies of chemical networks, some of the systems described display behavior that would be difficult to predict without the numerical simulations. Furthermore, the simulations reveal trends and characteristics that should be useful as "recipes" for future design of experimental functional motifs and for potential integration into modular circuits and molecular computation devices.

  5. Paying for express checkout: competition and price discrimination in multi-server queuing systems. (United States)

    Deck, Cary; Kimbrough, Erik O; Mongrain, Steeve


    We model competition between two firms selling identical goods to customers who arrive in the market stochastically. Shoppers choose where to purchase based upon both price and the time cost associated with waiting for service. One seller provides two separate queues, each with its own server, while the other seller has a single queue and server. We explore the market impact of the multi-server seller engaging in waiting cost-based-price discrimination by charging a premium for express checkout. Specifically, we analyze this situation computationally and through the use of controlled laboratory experiments. We find that this form of price discrimination is harmful to sellers and beneficial to consumers. When the two-queue seller offers express checkout for impatient customers, the single queue seller focuses on the patient shoppers thereby driving down prices and profits while increasing consumer surplus.

  6. Paying for express checkout: competition and price discrimination in multi-server queuing systems.

    Directory of Open Access Journals (Sweden)

    Cary Deck

    Full Text Available We model competition between two firms selling identical goods to customers who arrive in the market stochastically. Shoppers choose where to purchase based upon both price and the time cost associated with waiting for service. One seller provides two separate queues, each with its own server, while the other seller has a single queue and server. We explore the market impact of the multi-server seller engaging in waiting cost-based-price discrimination by charging a premium for express checkout. Specifically, we analyze this situation computationally and through the use of controlled laboratory experiments. We find that this form of price discrimination is harmful to sellers and beneficial to consumers. When the two-queue seller offers express checkout for impatient customers, the single queue seller focuses on the patient shoppers thereby driving down prices and profits while increasing consumer surplus.

  7. Characterizing and Managing Intrusion Detection System (IDS) Alerts with Multi-Server/Multi-Priority Queuing Theory (United States)


    assumed the buffer capacity and population are infinite and the service discipline is First Come, First Served (FCFS) or First In, First Out (FIFO). A...used. In these cases, it can be assumed the buffer capacity and population are infinite and the service discipline is First Come, First Served

  8. The role of protein interaction networks in systems biomedicine

    Directory of Open Access Journals (Sweden)

    Tuba Sevimoglu


    Full Text Available The challenging task of studying and modeling complex dynamics of biological systems in order to describe various human diseases has gathered great interest in recent years. Major biological processes are mediated through protein interactions, hence there is a need to understand the chaotic network that forms these processes in pursuance of understanding human diseases. The applications of protein interaction networks to disease datasets allow the identification of genes and proteins associated with diseases, the study of network properties, identification of subnetworks, and network-based disease gene classification. Although various protein interaction network analysis strategies have been employed, grand challenges are still existing. Global understanding of protein interaction networks via integration of high-throughput functional genomics data from different levels will allow researchers to examine the disease pathways and identify strategies to control them. As a result, it seems likely that more personalized, more accurate and more rapid disease gene diagnostic techniques will be devised in the future, as well as novel strategies that are more personalized. This mini-review summarizes the current practice of protein interaction networks in medical research as well as challenges to be overcome.

  9. Analysis of cellular manufacturing systems

    NARCIS (Netherlands)

    Heragu, Sunderesh; Zijm, Willem H.M.; Meng, Gang; Heragu, S.S.; van Ommeren, Jan C.W.; van Houtum, Geert-Jan


    In this paper, we present an open queuing network modeling approach to estimate performance measures of a cellular manufacturing layout. It is assumed a layout and production data for a planning period of specified length are available. The production data takes into account, processing and handling

  10. Console Networks for Major Computer Systems

    Energy Technology Data Exchange (ETDEWEB)

    Ophir, D; Shepherd, B; Spinrad, R J; Stonehill, D


    A concept for interactive time-sharing of a major computer system is developed in which satellite computers mediate between the central computing complex and the various individual user terminals. These techniques allow the development of a satellite system substantially independent of the details of the central computer and its operating system. Although the user terminals' roles may be rich and varied, the demands on the central facility are merely those of a tape drive or similar batched information transfer device. The particular system under development provides service for eleven visual display and communication consoles, sixteen general purpose, low rate data sources, and up to thirty-one typewriters. Each visual display provides a flicker-free image of up to 4000 alphanumeric characters or tens of thousands of points by employing a swept raster picture generating technique directly compatible with that of commercial television. Users communicate either by typewriter or a manually positioned light pointer.

  11. Penetration testing protecting networks and systems

    CERN Document Server

    Henry, Kevin M


    This book is a preparation guide for the CPTE examination, yet is also a general reference for experienced penetration testers, ethical hackers, auditors, security personnel and anyone else involved in the security of an organization's computer systems.

  12. Dynamic Business Networks: A Headache for Sustainable Systems Interoperability (United States)

    Agostinho, Carlos; Jardim-Goncalves, Ricardo

    Collaborative networked environments emerged with the spread of the internet, contributing to overcome past communication barriers, and identifying interoperability as an essential property. When achieved seamlessly, efficiency is increased in the entire product life cycle. Nowadays, most organizations try to attain interoperability by establishing peer-to-peer mappings with the different partners, or in optimized networks, by using international standard models as the core for information exchange. In current industrial practice, mappings are only defined once, and the morphisms that represent them, are hardcoded in the enterprise systems. This solution has been effective for static environments, where enterprise and product models are valid for decades. However, with an increasingly complex and dynamic global market, models change frequently to answer new customer requirements. This paper draws concepts from the complex systems science and proposes a framework for sustainable systems interoperability in dynamic networks, enabling different organizations to evolve at their own rate.

  13. An artificial neural network controller for intelligent transportation systems applications

    Energy Technology Data Exchange (ETDEWEB)

    Vitela, J.E.; Hanebutte, U.R.; Reifman, J. [Argonne National Lab., IL (United States). Reactor Analysis Div.


    An Autonomous Intelligent Cruise Control (AICC) has been designed using a feedforward artificial neural network, as an example for utilizing artificial neural networks for nonlinear control problems arising in intelligent transportation systems applications. The AICC is based on a simple nonlinear model of the vehicle dynamics. A Neural Network Controller (NNC) code developed at Argonne National Laboratory to control discrete dynamical systems was used for this purpose. In order to test the NNC, an AICC-simulator containing graphical displays was developed for a system of two vehicles driving in a single lane. Two simulation cases are shown, one involving a lead vehicle with constant velocity and the other a lead vehicle with varying acceleration. More realistic vehicle dynamic models will be considered in future work.

  14. Simulated, Emulated, and Physical Investigative Analysis (SEPIA) of networked systems.

    Energy Technology Data Exchange (ETDEWEB)

    Burton, David P.; Van Leeuwen, Brian P.; McDonald, Michael James; Onunkwo, Uzoma A.; Tarman, Thomas David; Urias, Vincent E.


    This report describes recent progress made in developing and utilizing hybrid Simulated, Emulated, and Physical Investigative Analysis (SEPIA) environments. Many organizations require advanced tools to analyze their information system's security, reliability, and resilience against cyber attack. Today's security analysis utilize real systems such as computers, network routers and other network equipment, computer emulations (e.g., virtual machines) and simulation models separately to analyze interplay between threats and safeguards. In contrast, this work developed new methods to combine these three approaches to provide integrated hybrid SEPIA environments. Our SEPIA environments enable an analyst to rapidly configure hybrid environments to pass network traffic and perform, from the outside, like real networks. This provides higher fidelity representations of key network nodes while still leveraging the scalability and cost advantages of simulation tools. The result is to rapidly produce large yet relatively low-cost multi-fidelity SEPIA networks of computers and routers that let analysts quickly investigate threats and test protection approaches.


    Directory of Open Access Journals (Sweden)

    V. V. Myamlin


    Full Text Available The algorithm of computer simulation of the flexible flow for repair of cars as a multiphase polychannel manyobject queuing system is presented. The basic operators of the model are given and their work is described.

  16. Spontaneous formation of dynamical groups in an adaptive networked system (United States)

    Li, Menghui; Guan, Shuguang; Lai, C.-H.


    In this work, we investigate a model of an adaptive networked dynamical system, where the coupling strengths among phase oscillators coevolve with the phase states. It is shown that in this model the oscillators can spontaneously differentiate into two dynamical groups after a long time evolution. Within each group, the oscillators have similar phases, while oscillators in different groups have approximately opposite phases. The network gradually converts from the initial random structure with a uniform distribution of connection strengths into a modular structure that is characterized by strong intra-connections and weak inter-connections. Furthermore, the connection strengths follow a power-law distribution, which is a natural consequence of the coevolution of the network and the dynamics. Interestingly, it is found that if the inter-connections are weaker than a certain threshold, the two dynamical groups will almost decouple and evolve independently. These results are helpful in further understanding the empirical observations in many social and biological networks.

  17. Systemic risk and heterogeneous leverage in banking networks (United States)

    Kuzubaş, Tolga Umut; Saltoğlu, Burak; Sever, Can


    This study probes systemic risk implications of leverage heterogeneity in banking networks. We show that the presence of heterogeneous leverages drastically changes the systemic effects of defaults and the nature of the contagion in interbank markets. Using financial leverage data from the US banking system, through simulations, we analyze the systemic significance of different types of borrowers, the evolution of the network, the consequences of interbank market size and the impact of market segmentation. Our study is related to the recent Basel III regulations on systemic risk and the treatment of the Global Systemically Important Banks (GSIBs). We also assess the extent to which the recent capital surcharges on GSIBs may curb financial fragility. We show the effectiveness of surcharge policy for the most-levered banks vis-a-vis uniform capital injection.

  18. Implementation of an integrated network of various ISR-systems (United States)

    Böker, D.


    Experiments were carried out at naval base Eckernförde, Germany, bringing together several projects concerning Defense Against Terrorism (DAT) and the net-centric battlespace. An integrated network of various Intelligence, Surveillance and Reconnaissance (ISR) systems was realized to evaluate the benefit of net-centric operations, i. e. in DAT focusing on force protection. ISR systems of the German Army, Air force, and Navy as well as a number of not yet operational systems were integrated in a joint network. Information relationships, data models, collaborative system functions and services were defined for as much as 27 systems from 20 companies. The NATO ISR Interoperability Architecture (NIIA) as the corner stone of technical standards for interoperable ISR products like images and motion imagery was used to the extent possible. Services and systems adopted by the multinational project MAJIIC were the starting point to develop appropriate collaboration tools and mechanisms.

  19. Adaptive traffic control systems for urban networks

    Directory of Open Access Journals (Sweden)

    Radivojević Danilo


    Full Text Available Adaptive traffic control systems represent complex, but powerful tool for improvement of traffic flow conditions in locations or zones where applied. Many traffic agencies, especially those that have a large number of signalized intersections with high variability of the traffic demand, choose to apply some of the adaptive traffic control systems. However, those systems are manufactured and offered by multiple vendors (companies that are competing for the market share. Due to that fact, besides the information available from the vendors themselves, or the information from different studies conducted on different continents, very limited amount of information is available about the details how those systems are operating. The reason for that is the protecting of the intellectual property from plagiarism. The primary goal of this paper is to make a brief analysis of the functionalities, characteristics, abilities and results of the most recognized, but also less known adaptive traffic control systems to the professional public and other persons with interest in this subject.

  20. Performance Evaluation of a Mobile Wireless Computational Grid ...

    African Journals Online (AJOL)



    Dec 1, 2015 ... theorem, each node is treated as an independent queuing system with a Poisson input determined by the principles of partitioning, merging or Tandem queuing. For both queuing networks (job despatch and compilation) an M/M/1 model is applied. (Figures 2 and 3). For an M/M/1 queue, let λ= arrival rate.

  1. Game-theoretic strategies for asymmetric networked systems

    Energy Technology Data Exchange (ETDEWEB)

    Rao, Nageswara S. [ORNL; Ma, Chris Y. T. [Hang Seng Management College, Hon Kong; Hausken, Kjell [University of Stavanger, Norway; He, Fei [Texas A& M University, Kingsville, TX, USA; Yau, David K. Y. [Singapore University of Technology and Design; Zhuang, Jun [University at Buffalo (SUNY)


    Abstract—We consider an infrastructure consisting of a network of systems each composed of discrete components that can be reinforced at a certain cost to guard against attacks. The network provides the vital connectivity between systems, and hence plays a critical, asymmetric role in the infrastructure operations. We characterize the system-level correlations using the aggregate failure correlation function that specifies the infrastructure failure probability given the failure of an individual system or network. The survival probabilities of systems and network satisfy first-order differential conditions that capture the component-level correlations. We formulate the problem of ensuring the infrastructure survival as a game between anattacker and a provider, using the sum-form and product-form utility functions, each composed of a survival probability term and a cost term. We derive Nash Equilibrium conditions which provide expressions for individual system survival probabilities, and also the expected capacity specified by the total number of operational components. These expressions differ only in a single term for the sum-form and product-form utilities, despite their significant differences.We apply these results to simplified models of distributed cloud computing infrastructures.

  2. Chemical reaction network approaches to Biochemical Systems Theory. (United States)

    Arceo, Carlene Perpetua P; Jose, Editha C; Marin-Sanguino, Alberto; Mendoza, Eduardo R


    This paper provides a framework to represent a Biochemical Systems Theory (BST) model (in either GMA or S-system form) as a chemical reaction network with power law kinetics. Using this representation, some basic properties and the application of recent results of Chemical Reaction Network Theory regarding steady states of such systems are shown. In particular, Injectivity Theory, including network concordance [36] and the Jacobian Determinant Criterion [43], a "Lifting Theorem" for steady states [26] and the comprehensive results of Müller and Regensburger [31] on complex balanced equilibria are discussed. A partial extension of a recent Emulation Theorem of Cardelli for mass action systems [3] is derived for a subclass of power law kinetic systems. However, it is also shown that the GMA and S-system models of human purine metabolism [10] do not display the reactant-determined kinetics assumed by Müller and Regensburger and hence only a subset of BST models can be handled with their approach. Moreover, since the reaction networks underlying many BST models are not weakly reversible, results for non-complex balanced equilibria are also needed. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Some thoughts on the control of network systems

    Directory of Open Access Journals (Sweden)

    Alessandro Ferrarini


    Full Text Available The controllability of network-like systems is becoming a trendy key-issue in many disciplines, including ecology and biology. To control a biological, ecological or economic system is to make it behave according to our wishes, at the least possible cost. In this paper, I propose some ideas on networks control that do not precisely follow recent papers on the argument. By the way, since this scientific topic is still in open evolution, discordant thoughts might be helpful to the debate.

  4. 1st International Conference on Signal, Networks, Computing, and Systems

    CERN Document Server

    Mohapatra, Durga; Nagar, Atulya; Sahoo, Manmath


    The book is a collection of high-quality peer-reviewed research papers presented in the first International Conference on Signal, Networks, Computing, and Systems (ICSNCS 2016) held at Jawaharlal Nehru University, New Delhi, India during February 25–27, 2016. The book is organized in to two volumes and primarily focuses on theory and applications in the broad areas of communication technology, computer science and information security. The book aims to bring together the latest scientific research works of academic scientists, professors, research scholars and students in the areas of signal, networks, computing and systems detailing the practical challenges encountered and the solutions adopted.

  5. Design of a Room Monitoring System for Wireless Sensor Networks


    Sun-Kuk Noh; Kuk-Se Kim; Yoo-Kang Ji


    In wireless sensor networks (WSN) systems, various indoor environmental parameters can be monitored in real time by an RF wireless sensor module. A wireless sensor module with several sensors is developed for an indoor environment monitoring system. ZigBee is a wireless standard for personal area network (PAN) sensor monitoring and control, also known as IEEE 802.15.4. In this paper, we designed a wireless sensor module that had a ZigBee communication module and a sensor module for monitoring...

  6. Integrated Network Analysis and Effective Tools in Plant Systems Biology

    Directory of Open Access Journals (Sweden)

    Atsushi eFukushima


    Full Text Available One of the ultimate goals in plant systems biology is to elucidate the genotype-phenotype relationship in plant cellular systems. Integrated network analysis that combines omics data with mathematical models has received particular attention. Here we focus on the latest cutting-edge computational advances that facilitate their combination. We highlight (1 network visualization tools, (2 pathway analyses, (3 genome-scale metabolic reconstruction, and (4 the integration of high-throughput experimental data and mathematical models. Multi-omics data that contain the genome, transcriptome, proteome, and metabolome and mathematical models are expected to integrate and expand our knowledge of complex plant metabolisms.

  7. Stochastic network optimization with application to communication and queueing systems

    CERN Document Server

    Neely, Michael


    This text presents a modern theory of analysis, control, and optimization for dynamic networks. Mathematical techniques of Lyapunov drift and Lyapunov optimization are developed and shown to enable constrained optimization of time averages in general stochastic systems. The focus is on communication and queueing systems, including wireless networks with time-varying channels, mobility, and randomly arriving traffic. A simple drift-plus-penalty framework is used to optimize time averages such as throughput, throughput-utility, power, and distortion. Explicit performance-delay tradeoffs are prov

  8. Hybrid Networks and Risk Management in a System Perspective

    DEFF Research Database (Denmark)

    Nørgaard, Katrine

    intelligent, autonomous systems and human operators in multi-domain Battle Management Networks, (i.e Command, Control, Communications, Computer and Intelligence (C4I) networks/sensor grids). However, the incorporation of intelligent and autonomous weapon systems in complex military operations introduces both...... new possibilities and new types of risk, as well as legal and ethical concerns. At the same time, the rapid acceleration and hybridization of the battlespace challenges the classical military bureaucracies and its legal-rational decision-making processes. This paper will address some of the legal...

  9. Research of dynamic load balancing based on the UMTS-SGSN system (United States)

    Wang, Furong; Teng, Zuwei


    During the distributed design of UMTS-SGSN system, the Dynamic Central Tasks Scheduling algorithm (DCTS) with good real-time property is researched to meet the hard requirements of bandwidth and latency of UMTS-SGSN system. Based on the assumption without task migration, Markov queuing network model is used to model UMTS-SGSN system instead of M/M/c queuing model. For single user with one PDP context, DCTS is optimal through the theoretic calculation and simulation. And for single user with not less than one PDP context, the performance of DCTS is discussed through the simulation. In the case of longer service time in data service, DCTS is compared with stochastic scheduling algorithm and cycle scheduling algorithm. Simulation results show that DCTS is better than other two algorithms, and when service time is shorter, three algorithms' performance is approximately same. The performances of the three algorithms in different service time are also analyzed by adjusting the parameter μ of the exponential distribution. Results show that exponential distribution's heavy-tailed effect of the service time leads to deteriorating the efficiency of load balancing and DCTS shall initiate less task migration and decrease system overhead.

  10. Application of geographic information system in distribution power network automation (United States)

    Wei, Xianmin


    Geographic information system (GIS) is the computer system in support of computer software with collection, storage, management, retrieval and comprehensive analysis of a variety of geospatial information, with various forms output data and graphics products. This paper introduced GIS data organization and its main applications in distribution power network automation, including both offline and online, and proposed component-based system development model and the need to establish WEBGIS and reliability.

  11. An intelligent management system for corporate information- calculating network development

    CERN Document Server

    Pirogov, V V; Khristenko, D V


    An approach to solving the problem of managerial control quality improvement corporate information-calculating networks (CICN) is proposed. The approach is based on the concept of a flexible toolkit. A macro-model, system-science and system-engineering models of an intelligent managerial control system (IMCS) for CICN development are considered as well as its dynamics. The practical opportunity of IMCS implementation is assessed. (5 refs).

  12. The Network Configuration of an Object Relational Database Management System (United States)

    Diaz, Philip; Harris, W. C.


    The networking and implementation of the Oracle Database Management System (ODBMS) requires developers to have knowledge of the UNIX operating system as well as all the features of the Oracle Server. The server is an object relational database management system (DBMS). By using distributed processing, processes are split up between the database server and client application programs. The DBMS handles all the responsibilities of the server. The workstations running the database application concentrate on the interpretation and display of data.

  13. Signal-regulated systems and networks

    CSIR Research Space (South Africa)

    Van Zyl, TL


    Full Text Available been extended by Decraene [?, 33]. The work presented here builds on this body of knowledge. The research problem is twofold. On one hand building IT systems that ex- hibit the properties of self-organising CAS is required. On the other hand IT sys... to disruptions and stresses to assess its robustness, scalability and adaptability. The data collected takes the form of the number of work items that each agent within the system is able to perform along with how many work items fail and are completed...

  14. Enterprise network intrusion detection and prevention system (ENIDPS) (United States)

    Akujuobi, C. M.; Ampah, N. K.


    Securing enterprise networks comes under two broad topics: Intrusion Detection Systems (IDS) and Intrusion Prevention Systems (IPS). The right combination of selected algorithms/techniques under both topics produces better security for a given network. This approach leads to using layers of physical, administrative, electronic, and encrypted systems to protect valuable resources. So far, there is no algorithm, which guarantees absolute protection for a given network from intruders. Intrusion Prevention Systems like IPSec, Firewall, Sender ID, Domain Keys Identified Mail (DKIM) etc. do not guarantee absolute security just like existing Intrusion Detection Systems. Our approach focuses on developing an IDS, which will detect all intruders that bypass the IPS and at the same time will be used in updating the IPS, since the IPS fail to prevent some intruders from entering a given network. The new IDS will employ both signature-based detection and anomaly detection as its analysis strategy. It should therefore be able to detect known and unknown intruders or attacks and further isolate those sources of attack within the network. Both real-time and off-line IDS predictions will be applied under the analysis and response stages. The basic IDS architecture will involve both centralized and distributed/heterogeneous architecture to ensure effective detection. Pro-active responses and corrective responses will be employed. The new security system, which will be made up of both IDS and IPS, should be less expensive to implement compared to existing ones. Finally, limitations of existing security systems have to be eliminated with the introduction of the new security system.

  15. Pathways, Networks, and Systems: Theory and Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Joseph H. Nadeau; John D. Lambris


    The international conference provided a unique opportunity for theoreticians and experimenters to exchange ideas, strategies, problems, challenges, language and opportunities in both formal and informal settings. This dialog is an important step towards developing a deep and effective integration of theory and experiments in studies of systems biology in humans and model organisms.

  16. STAR Network Distributed Computer Systems Evaluation Results. (United States)


    image processing systems. Further, because of the small data require- ments a segment of TOTT is a good candidate for VLSI. It can attain the...broadcast capabilities of the distributed architecture to isolate the overhead of accounting and enhacing of fault isolation (see Figure B-1). B-1 The

  17. Vulnerability Analysis of Urban Drainage Systems: Tree vs. Loop Networks

    Directory of Open Access Journals (Sweden)

    Chi Zhang


    Full Text Available Vulnerability analysis of urban drainage networks plays an important role in urban flood management. This study analyzes and compares the vulnerability of tree and loop systems under various rainfall events to structural failure represented by pipe blockage. Different pipe blockage scenarios, in which one of the pipes in an urban drainage network is assumed to be blocked individually, are constructed and their impacts on the network are simulated under different storm events. Furthermore, a vulnerability index is defined to measure the vulnerability of the drainage systems before and after the implementation of adaptation measures. The results obtained indicate that the tree systems have a relatively larger proportion of critical hydraulic pipes than the loop systems, thus the vulnerability of tree systems is substantially greater than that of the loop systems. Furthermore, the vulnerability index of tree systems is reduced after they are converted into a loop system with the implementation of adaptation measures. This paper provides an insight into the differences in the vulnerability of tree and loop systems, and provides more evidence for development of adaptation measures (e.g., tanks to reduce urban flooding.

  18. Neural-network-based fuzzy logic decision systems (United States)

    Kulkarni, Arun D.; Giridhar, G. B.; Coca, Praveen


    During the last few years there has been a large and energetic upswing in research efforts aimed at synthesizing fuzzy logic with neural networks. This combination of neural networks and fuzzy logic seems natural because the two approaches generally attack the design of `intelligent' system from quite different angles. Neural networks provide algorithms for learning, classification, and optimization whereas fuzzy logic often deals with issues such as reasoning in a high (semantic or linguistic) level. Consequently the two technologies complement each other. In this paper, we combine neural networks with fuzzy logic techniques. We propose an artificial neural network (ANN) model for a fuzzy logic decision system. The model consists of six layers. The first three layers map the input variables to fuzzy set membership functions. The last three layers implement the decision rules. The model learns the decision rules using a supervised gradient descent procedure. As an illustration we considered two examples. The first example deals with pixel classification in multispectral satellite images. In our second example we used the fuzzy decision system to analyze data from magnetic resonance imaging (MRI) scans for tissue classification.

  19. A graph-based system for network-vulnerability analysis

    Energy Technology Data Exchange (ETDEWEB)

    Swiler, L.P.; Phillips, C.


    This paper presents a graph-based approach to network vulnerability analysis. The method is flexible, allowing analysis of attacks from both outside and inside the network. It can analyze risks to a specific network asset, or examine the universe of possible consequences following a successful attack. The graph-based tool can identify the set of attack paths that have a high probability of success (or a low effort cost) for the attacker. The system could be used to test the effectiveness of making configuration changes, implementing an intrusion detection system, etc. The analysis system requires as input a database of common attacks, broken into atomic steps, specific network configuration and topology information, and an attacker profile. The attack information is matched with the network configuration information and an attacker profile to create a superset attack graph. Nodes identify a stage of attack, for example the class of machines the attacker has accessed and the user privilege level he or she has compromised. The arcs in the attack graph represent attacks or stages of attacks. By assigning probabilities of success on the arcs or costs representing level-of-effort for the attacker, various graph algorithms such as shortest-path algorithms can identify the attack paths with the highest probability of success.

  20. Reliability Modeling of Microelectromechanical Systems Using Neural Networks (United States)

    Perera. J. Sebastian


    Microelectromechanical systems (MEMS) are a broad and rapidly expanding field that is currently receiving a great deal of attention because of the potential to significantly improve the ability to sense, analyze, and control a variety of processes, such as heating and ventilation systems, automobiles, medicine, aeronautical flight, military surveillance, weather forecasting, and space exploration. MEMS are very small and are a blend of electrical and mechanical components, with electrical and mechanical systems on one chip. This research establishes reliability estimation and prediction for MEMS devices at the conceptual design phase using neural networks. At the conceptual design phase, before devices are built and tested, traditional methods of quantifying reliability are inadequate because the device is not in existence and cannot be tested to establish the reliability distributions. A novel approach using neural networks is created to predict the overall reliability of a MEMS device based on its components and each component's attributes. The methodology begins with collecting attribute data (fabrication process, physical specifications, operating environment, property characteristics, packaging, etc.) and reliability data for many types of microengines. The data are partitioned into training data (the majority) and validation data (the remainder). A neural network is applied to the training data (both attribute and reliability); the attributes become the system inputs and reliability data (cycles to failure), the system output. After the neural network is trained with sufficient data. the validation data are used to verify the neural networks provided accurate reliability estimates. Now, the reliability of a new proposed MEMS device can be estimated by using the appropriate trained neural networks developed in this work.

  1. Real-Time Alpine Measurement System Using Wireless Sensor Networks. (United States)

    Malek, Sami A; Avanzi, Francesco; Brun-Laguna, Keoma; Maurer, Tessa; Oroza, Carlos A; Hartsough, Peter C; Watteyne, Thomas; Glaser, Steven D


    Monitoring the snow pack is crucial for many stakeholders, whether for hydro-power optimization, water management or flood control. Traditional forecasting relies on regression methods, which often results in snow melt runoff predictions of low accuracy in non-average years. Existing ground-based real-time measurement systems do not cover enough physiographic variability and are mostly installed at low elevations. We present the hardware and software design of a state-of-the-art distributed Wireless Sensor Network (WSN)-based autonomous measurement system with real-time remote data transmission that gathers data of snow depth, air temperature, air relative humidity, soil moisture, soil temperature, and solar radiation in physiographically representative locations. Elevation, aspect, slope and vegetation are used to select network locations, and distribute sensors throughout a given network location, since they govern snow pack variability at various scales. Three WSNs were installed in the Sierra Nevada of Northern California throughout the North Fork of the Feather River, upstream of the Oroville dam and multiple powerhouses along the river. The WSNs gathered hydrologic variables and network health statistics throughout the 2017 water year, one of northern Sierra's wettest years on record. These networks leverage an ultra-low-power wireless technology to interconnect their components and offer recovery features, resilience to data loss due to weather and wildlife disturbances and real-time topological visualizations of the network health. Data show considerable spatial variability of snow depth, even within a 1 km 2 network location. Combined with existing systems, these WSNs can better detect precipitation timing and phase in, monitor sub-daily dynamics of infiltration and surface runoff during precipitation or snow melt, and inform hydro power managers about actual ablation and end-of-season date across the landscape.

  2. Real-Time Alpine Measurement System Using Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Sami A. Malek


    Full Text Available Monitoring the snow pack is crucial for many stakeholders, whether for hydro-power optimization, water management or flood control. Traditional forecasting relies on regression methods, which often results in snow melt runoff predictions of low accuracy in non-average years. Existing ground-based real-time measurement systems do not cover enough physiographic variability and are mostly installed at low elevations. We present the hardware and software design of a state-of-the-art distributed Wireless Sensor Network (WSN-based autonomous measurement system with real-time remote data transmission that gathers data of snow depth, air temperature, air relative humidity, soil moisture, soil temperature, and solar radiation in physiographically representative locations. Elevation, aspect, slope and vegetation are used to select network locations, and distribute sensors throughout a given network location, since they govern snow pack variability at various scales. Three WSNs were installed in the Sierra Nevada of Northern California throughout the North Fork of the Feather River, upstream of the Oroville dam and multiple powerhouses along the river. The WSNs gathered hydrologic variables and network health statistics throughout the 2017 water year, one of northern Sierra’s wettest years on record. These networks leverage an ultra-low-power wireless technology to interconnect their components and offer recovery features, resilience to data loss due to weather and wildlife disturbances and real-time topological visualizations of the network health. Data show considerable spatial variability of snow depth, even within a 1 km 2 network location. Combined with existing systems, these WSNs can better detect precipitation timing and phase in, monitor sub-daily dynamics of infiltration and surface runoff during precipitation or snow melt, and inform hydro power managers about actual ablation and end-of-season date across the landscape.

  3. Determining Application Runtimes Using Queueing Network Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Elliott, Michael L. [Univ. of San Francisco, CA (United States)


    Determination of application times-to-solution for large-scale clustered computers continues to be a difficult problem in high-end computing, which will only become more challenging as multi-core consumer machines become more prevalent in the market. Both researchers and consumers of these multi-core systems desire reasonable estimates of how long their programs will take to run (time-to-solution, or TTS), and how many resources will be consumed in the execution. Currently there are few methods of determining these values, and those that do exist are either overly simplistic in their assumptions or require great amounts of effort to parameterize and understand. One previously untried method is queuing network modeling (QNM), which is easy to parameterize and solve, and produces results that typically fall within 10 to 30% of the actual TTS for our test cases. Using characteristics of the computer network (bandwidth, latency) and communication patterns (number of messages, message length, time spent in communication), the QNM model of the NAS-PB CG application was applied to MCR and ALC, supercomputers at LLNL, and the Keck Cluster at USF, with average errors of 2.41%, 3.61%, and -10.73%, respectively, compared to the actual TTS observed. While additional work is necessary to improve the predictive capabilities of QNM, current results show that QNM has a great deal of promise for determining application TTS for multi-processor computer systems.

  4. Stochastic Optimization for Network-Constrained Power System Scheduling Problem

    Directory of Open Access Journals (Sweden)

    D. F. Teshome


    Full Text Available The stochastic nature of demand and wind generation has a considerable effect on solving the scheduling problem of a modern power system. Network constraints such as power flow equations and transmission capacities also need to be considered for a comprehensive approach to model renewable energy integration and analyze generation system flexibility. Firstly, this paper accounts for the stochastic inputs in such a way that the uncertainties are modeled as normally distributed forecast errors. The forecast errors are then superimposed on the outputs of load and wind forecasting tools. Secondly, it efficiently models the network constraints and tests an iterative algorithm and a piecewise linear approximation for representing transmission losses in mixed integer linear programming (MILP. It also integrates load shedding according to priority factors set by the system operator. Moreover, the different interactions among stochastic programming, network constraints, and prioritized load shedding are thoroughly investigated in the paper. The stochastic model is tested on a power system adopted from Jeju Island, South Korea. Results demonstrate the impact of wind speed variability and network constraints on the flexibility of the generation system. Further analysis shows the effect of loss modeling approaches on total cost, accuracy, computational time, and memory requirement.

  5. Collaborative Networked Organizations as System of Systems: A Model-Based Engineering Approach


    Bilal, Mustapha; Daclin, Nicolas; Chapurlat, Vincent


    Part 6: Engineering and Implementation of Collaborative Networks; International audience; It is admitted that there is parallel between a System of Systems (SoS) and Collaborative Networked Organizations (CNOs). SoS Engineering (SoSE) carefully focuses on choosing, assembling and interfacing existing systems to build the so-called SoS. In this context, and as demonstrated by the literature and the System Engineering domain, interoperability takes on its full meaning and has to be fully consid...

  6. An artificial bioindicator system for network intrusion detection. (United States)

    Blum, Christian; Lozano, José A; Davidson, Pedro Pinacho


    An artificial bioindicator system is developed in order to solve a network intrusion detection problem. The system, inspired by an ecological approach to biological immune systems, evolves a population of agents that learn to survive in their environment. An adaptation process allows the transformation of the agent population into a bioindicator that is capable of reacting to system anomalies. Two characteristics stand out in our proposal. On the one hand, it is able to discover new, previously unseen attacks, and on the other hand, contrary to most of the existing systems for network intrusion detection, it does not need any previous training. We experimentally compare our proposal with three state-of-the-art algorithms and show that it outperforms the competing approaches on widely used benchmark data.

  7. Sensor network based vehicle classification and license plate identification system

    Energy Technology Data Exchange (ETDEWEB)

    Frigo, Janette Rose [Los Alamos National Laboratory; Brennan, Sean M [Los Alamos National Laboratory; Rosten, Edward J [Los Alamos National Laboratory; Raby, Eric Y [Los Alamos National Laboratory; Kulathumani, Vinod K [WEST VIRGINIA UNIV.


    Typically, for energy efficiency and scalability purposes, sensor networks have been used in the context of environmental and traffic monitoring applications in which operations at the sensor level are not computationally intensive. But increasingly, sensor network applications require data and compute intensive sensors such video cameras and microphones. In this paper, we describe the design and implementation of two such systems: a vehicle classifier based on acoustic signals and a license plate identification system using a camera. The systems are implemented in an energy-efficient manner to the extent possible using commercially available hardware, the Mica motes and the Stargate platform. Our experience in designing these systems leads us to consider an alternate more flexible, modular, low-power mote architecture that uses a combination of FPGAs, specialized embedded processing units and sensor data acquisition systems.

  8. Networked vision system using a Prolog controller (United States)

    Batchelor, B. G.; Caton, S. J.; Chatburn, L. T.; Crowther, R. A.; Miller, J. W. V.


    Prolog offers a very different style of programming compared to conventional languages; it can define object properties and abstract relationships in a way that Java, C, C++, etc. find awkward. In an accompanying paper, the authors describe how a distributed web-based vision systems can be built using elements that may even be located on different continents. One particular system of this general type is described here. The top-level controller is a Prolog program, which operates one, or more, image processing engines. This type of function is natural to Prolog, since it is able to reason logically using symbolic (non-numeric) data. Although Prolog is not suitable for programming image processing functions directly, it is ideal for analysing the results derived by an image processor. This article describes the implementation of two systems, in which a Prolog program controls several image processing engines, a simple robot, a pneumatic pick-and-place arm), LED illumination modules and a various mains-powered devices.


    Directory of Open Access Journals (Sweden)

    Usham Dias


    Full Text Available This paper presents biometric personal identification based on iris recognition using artificial neural networks. Personal identification system consists of localization of the iris region, normalization, enhancement and then iris pattern recognition using neural network. In this paper, through results obtained, we have shown that a person’s left and right eye are unique. In this paper, we also show that the network is sensitive to the initial weights and that over-training gives bad results. We also propose a fast algorithm for the localization of the inner and outer boundaries of the iris region. Results of simulations illustrate the effectiveness of the neural system in personal identification. Finally a hardware iris recognition model is proposed and implementation aspects are discussed.

  10. Future cooperative communication systems driven by social mobile networks

    DEFF Research Database (Denmark)

    Blázovics, L.; Varga, C.; Bamford, W.


    In this work we are underlining the importance of social mobile networks for upcoming cooperative communication systems. The assumption of this work is that future mobile communication systems will incorporate user cooperation, i.e. a combination of cellular access in parallel with ongoing short...... range links to the neighboring devices. It has been shown that user cooperation enables higher data rates, better spectral efficiencies, and reduces the energy consumption of the mobile unit. In this work the social mobile networks are identified to be a fertile ground to facilitate the cooperative use...... cases. By the example of the Gedda-Headz gaming community, possible links between cooperative mobile communication and social mobile networks are shown....

  11. A cognitive fault diagnosis system for distributed sensor networks. (United States)

    Alippi, Cesare; Ntalampiras, Stavros; Roveri, Manuel


    This paper introduces a novel cognitive fault diagnosis system (FDS) for distributed sensor networks that takes advantage of spatial and temporal relationships among sensors. The proposed FDS relies on a suitable functional graph representation of the network and a two-layer hierarchical architecture designed to promptly detect and isolate faults. The lower processing layer exploits a novel change detection test (CDT) based on hidden Markov models (HMMs) configured to detect variations in the relationships between couples of sensors. HMMs work in the parameter space of linear time-invariant dynamic systems, approximating, over time, the relationship between two sensors; changes in the approximating model are detected by inspecting the HMM likelihood. Information provided by the CDT layer is then passed to the cognitive one, which, by exploiting the graph representation of the network, aggregates information to discriminate among faults, changes in the environment, and false positives induced by the model bias of the HMMs.

  12. A system of recurrent neural networks for modularising, parameterising and dynamic analysis of cell signalling networks. (United States)

    Samarasinghe, S; Ling, H

    In this paper, we show how to extend our previously proposed novel continuous time Recurrent Neural Networks (RNN) approach that retains the advantage of continuous dynamics offered by Ordinary Differential Equations (ODE) while enabling parameter estimation through adaptation, to larger signalling networks using a modular approach. Specifically, the signalling network is decomposed into several sub-models based on important temporal events in the network. Each sub-model is represented by the proposed RNN and trained using data generated from the corresponding ODE model. Trained sub-models are assembled into a whole system RNN which is then subjected to systems dynamics and sensitivity analyses. The concept is illustrated by application to G1/S transition in cell cycle using Iwamoto et al. (2008) ODE model. We decomposed the G1/S network into 3 sub-models: (i) E2F transcription factor release; (ii) E2F and CycE positive feedback loop for elevating cyclin levels; and (iii) E2F and CycA negative feedback to degrade E2F. The trained sub-models accurately represented system dynamics and parameters were in good agreement with the ODE model. The whole system RNN however revealed couple of parameters contributing to compounding errors due to feedback and required refinement to sub-model 2. These related to the reversible reaction between CycE/CDK2 and p27, its inhibitor. The revised whole system RNN model very accurately matched dynamics of the ODE system. Local sensitivity analysis of the whole system model further revealed the most dominant influence of the above two parameters in perturbing G1/S transition, giving support to a recent hypothesis that the release of inhibitor p27 from Cyc/CDK complex triggers cell cycle stage transition. To make the model useful in a practical setting, we modified each RNN sub-model with a time relay switch to facilitate larger interval input data (≈20min) (original model used data for 30s or less) and retrained them that produced

  13. The Accounting Network: How Financial Institutions React to Systemic Crisis. (United States)

    Puliga, Michelangelo; Flori, Andrea; Pappalardo, Giuseppe; Chessa, Alessandro; Pammolli, Fabio


    The role of Network Theory in the study of the financial crisis has been widely spotted in the latest years. It has been shown how the network topology and the dynamics running on top of it can trigger the outbreak of large systemic crisis. Following this methodological perspective we introduce here the Accounting Network, i.e. the network we can extract through vector similarities techniques from companies' financial statements. We build the Accounting Network on a large database of worldwide banks in the period 2001-2013, covering the onset of the global financial crisis of mid-2007. After a careful data cleaning, we apply a quality check in the construction of the network, introducing a parameter (the Quality Ratio) capable of trading off the size of the sample (coverage) and the representativeness of the financial statements (accuracy). We compute several basic network statistics and check, with the Louvain community detection algorithm, for emerging communities of banks. Remarkably enough sensible regional aggregations show up with the Japanese and the US clusters dominating the community structure, although the presence of a geographically mixed community points to a gradual convergence of banks into similar supranational practices. Finally, a Principal Component Analysis procedure reveals the main economic components that influence communities' heterogeneity. Even using the most basic vector similarity hypotheses on the composition of the financial statements, the signature of the financial crisis clearly arises across the years around 2008. We finally discuss how the Accounting Networks can be improved to reflect the best practices in the financial statement analysis.

  14. The Accounting Network: How Financial Institutions React to Systemic Crisis.

    Directory of Open Access Journals (Sweden)

    Michelangelo Puliga

    Full Text Available The role of Network Theory in the study of the financial crisis has been widely spotted in the latest years. It has been shown how the network topology and the dynamics running on top of it can trigger the outbreak of large systemic crisis. Following this methodological perspective we introduce here the Accounting Network, i.e. the network we can extract through vector similarities techniques from companies' financial statements. We build the Accounting Network on a large database of worldwide banks in the period 2001-2013, covering the onset of the global financial crisis of mid-2007. After a careful data cleaning, we apply a quality check in the construction of the network, introducing a parameter (the Quality Ratio capable of trading off the size of the sample (coverage and the representativeness of the financial statements (accuracy. We compute several basic network statistics and check, with the Louvain community detection algorithm, for emerging communities of banks. Remarkably enough sensible regional aggregations show up with the Japanese and the US clusters dominating the community structure, although the presence of a geographically mixed community points to a gradual convergence of banks into similar supranational practices. Finally, a Principal Component Analysis procedure reveals the main economic components that influence communities' heterogeneity. Even using the most basic vector similarity hypotheses on the composition of the financial statements, the signature of the financial crisis clearly arises across the years around 2008. We finally discuss how the Accounting Networks can be improved to reflect the best practices in the financial statement analysis.

  15. Development of Network Analysis and Visualization System for KEGG Pathways

    Directory of Open Access Journals (Sweden)

    Dongmin Seo


    Full Text Available Big data refers to informationalization technology for extracting valuable information through the use and analysis of large-scale data and, based on that data, deriving plans for response or predicting changes. With the development of software and devices for next generation sequencing, a vast amount of bioinformatics data has been generated recently. Also, bioinformatics data based big-data technology is rising rapidly as a core technology by the bioinformatician, biologist and big-data scientist. KEGG pathway is bioinformatics data for understanding high-level functions and utilities of the biological system. However, KEGG pathway analysis requires a lot of time and effort because KEGG pathways are high volume and very diverse. In this paper, we proposed a network analysis and visualization system that crawl user interest KEGG pathways, construct a pathway network based on a hierarchy structure of pathways and visualize relations and interactions of pathways by clustering and selecting core pathways from the network. Finally, we construct a pathway network collected by starting with an Alzheimer’s disease pathway and show the results on clustering and selecting core pathways from the pathway network.

  16. Optimum Water Quality Monitoring Network Design for Bidirectional River Systems. (United States)

    Zhu, Xiaohui; Yue, Yong; Wong, Prudence W H; Zhang, Yixin; Tan, Jianhong


    Affected by regular tides, bidirectional water flows play a crucial role in surface river systems. Using optimization theory to design a water quality monitoring network can reduce the redundant monitoring nodes as well as save the costs for building and running a monitoring network. A novel algorithm is proposed to design an optimum water quality monitoring network for tidal rivers with bidirectional water flows. Two optimization objectives of minimum pollution detection time and maximum pollution detection probability are used in our optimization algorithm. We modify the Multi-Objective Particle Swarm Optimization (MOPSO) algorithm and develop new fitness functions to calculate pollution detection time and pollution detection probability in a discrete manner. In addition, the Storm Water Management Model (SWMM) is used to simulate hydraulic characteristics and pollution events based on a hypothetical river system studied in the literature. Experimental results show that our algorithm can obtain a better Pareto frontier. The influence of bidirectional water flows to the network design is also identified, which has not been studied in the literature. Besides that, we also find that the probability of bidirectional water flows has no effect on the optimum monitoring network design but slightly changes the mean pollution detection time.

  17. Optimum Water Quality Monitoring Network Design for Bidirectional River Systems

    Directory of Open Access Journals (Sweden)

    Xiaohui Zhu


    Full Text Available Affected by regular tides, bidirectional water flows play a crucial role in surface river systems. Using optimization theory to design a water quality monitoring network can reduce the redundant monitoring nodes as well as save the costs for building and running a monitoring network. A novel algorithm is proposed to design an optimum water quality monitoring network for tidal rivers with bidirectional water flows. Two optimization objectives of minimum pollution detection time and maximum pollution detection probability are used in our optimization algorithm. We modify the Multi-Objective Particle Swarm Optimization (MOPSO algorithm and develop new fitness functions to calculate pollution detection time and pollution detection probability in a discrete manner. In addition, the Storm Water Management Model (SWMM is used to simulate hydraulic characteristics and pollution events based on a hypothetical river system studied in the literature. Experimental results show that our algorithm can obtain a better Pareto frontier. The influence of bidirectional water flows to the network design is also identified, which has not been studied in the literature. Besides that, we also find that the probability of bidirectional water flows has no effect on the optimum monitoring network design but slightly changes the mean pollution detection time.

  18. Role of Communication Networks in Behavioral Systems Analysis (United States)

    Houmanfar, Ramona; Rodrigues, Nischal Joseph; Smith, Gregory S.


    This article provides an overview of communication networks and the role of verbal behavior in behavioral systems analysis. Our discussion highlights styles of leadership in the design and implementation of effective organizational contingencies that affect ways by which coordinated work practices are managed. We draw upon literature pertaining to…

  19. Reduction of Second-Order Network Systems with Structure Preservation

    NARCIS (Netherlands)

    Cheng, Xiaodong; Kawano, Yu; Scherpen, Jacquelien M.A.


    This paper proposes a general framework for structure-preserving model reduction of a second-order network system based on graph clustering. In this approach, vertex dynamics are captured by the transfer functions from inputs to individual states, and the dissimilarities of vertices are quantified

  20. Classical Conditioning with Pulsed Integrated Neural Networks: Circuits and System

    DEFF Research Database (Denmark)

    Lehmann, Torsten


    In this paper we investigate on-chip learning for pulsed, integrated neural networks. We discuss the implementational problems the technology imposes on learning systems and we find that abiologically inspired approach using simple circuit structures is most likely to bring success. We develop a ...... chip to solve simple classical conditioning tasks, thus verifying the design methodologies put forward in the paper....