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Showing papers on "Bus network published in 2015"


Journal ArticleDOI
21 May 2015-Energies
TL;DR: In this paper, the authors analyze how and to what extent existing bus networks can be electrified with fast charging battery buses, and the impact on the electricity grid is discussed based on the load profiles of a selected charging station and a combined load profile of the entire network.
Abstract: The electrification of public transport bus networks can be carried out utilizing different technological solutions, like trolley, battery or fuel cell buses. The purpose of this paper is to analyze how and to what extent existing bus networks can be electrified with fast charging battery buses. The so called opportunity chargers use mainly the regular dwell time at the stops to charge their batteries. This results in a strong linkage between the vehicle scheduling and the infrastructure planning. The analysis is based on real-world data of the bus network in Muenster, a mid-sized city in Germany. The outcomes underline the necessity to focus on entire vehicle schedules instead on individual trips. The tradeoff between required battery capacity and charging power is explained in detail. Furthermore, the impact on the electricity grid is discussed based on the load profiles of a selected charging station and a combined load profile of the entire network.

172 citations


Journal ArticleDOI
TL;DR: Analytical and simulated results are given to show the impact of different properties weights to the public traffic network balance in the urban traffic network models with multi-weights with single bus transfer junction.
Abstract: Regarding single bus transfer junction as a research object, this paper constructs the urban traffic network models with multi-weights taking different bus lines in bus transfer junction as the network nodes, that is, the urban traffic network with multi-weights is given different properties weights at every edge. According to the method of network split, the complex network with multi-weights is split into several different single weighted complex networks. Then, we study the global synchronization of the new network model by changing congestion degrees, transfers coefficient and passenger flow density between different bus lines. Finally, analytical and simulated results are given to show the impact of different properties weights to the public traffic network balance.

72 citations


Journal ArticleDOI
TL;DR: It is found that adding slack time into timetable greatly benefits transferring passengers by reducing the rate of transferring failure and a stochastic integer programming model for the BTP-STT is developed to minimize the total waiting time cost for three types of passengers.
Abstract: Transit network timetabling aims at determining the departure time of each trip of all lines in order to facilitate passengers transferring either to or from a bus. In this paper, we consider a bus timetabling problem with stochastic travel times (BTP-STT). Slack time is added into timetable to mitigate the randomness in bus travel times. We then develop a stochastic integer programming model for the BTP-STT to minimize the total waiting time cost for three types of passengers (i.e., transferring passengers, boarding passengers and through passengers). The mathematical properties of the model are characterized. Due to its computational complexity, a genetic algorithm with local search (GALS) is designed to solve our proposed model (OPM). The numerical results based on a small bus network show that the timetable obtained from OPM reduces the total waiting time cost by an average of 9.5%, when it is tested in different scenarios. OPM is relatively effective if the ratio of the number of through passengers to the number of transferring passengers is not larger than a threshold (e.g., 10 in our case). In addition, we test different scale instances randomly generated in a practical setting to further verify the effectiveness of OPM and GALS. We also find that adding slack time into timetable greatly benefits transferring passengers by reducing the rate of transferring failure.

68 citations


Journal ArticleDOI
01 Mar 2015-Networks
TL;DR: The results show that allowing transfers reduces total operating costs significantly while average and maximum user ride times are comparable to solutions without transfers.
Abstract: In this article, we study the school bus routing and scheduling problem with transfers arising in the field of nonperiodic public transportation systems. It deals with the transportation of pupils from home to their school in the morning taking the possibility that pupils may change buses into account. Allowing transfers has several consequences. On the one hand, it allows more flexibility in the bus network structure and can, therefore, help to reduce operating costs. On the other hand, transfers have an impact on the service level: the perceived service quality is lower due to the existence of transfers; however, at the same time, user ride times may be reduced and, thus, transfers may also have a positive impact on service quality. The main objective is the minimization of the total operating costs. We develop a heuristic solution framework to solve this problem and compare it with two solution concepts that do not consider transfers. The impact of transfers on the service level in terms of time loss or user ride time and the number of transfers is analyzed. Our results show that allowing transfers reduces total operating costs significantly while average and maximum user ride times are comparable to solutions without transfers. © 2015 Wiley Periodicals, Inc. NETWORKS, Vol. 652, 180-203 2015

63 citations


Journal ArticleDOI
TL;DR: It is uncovered that the efficiency of the city traffic system has a non-equilibrium phase transition at low capacity of the networks, which explains why the pressure of the traffic overload is relaxed by singly increasing the number of small buses during rush hours.
Abstract: The vulnerability to real-life networks against small initial attacks has been one of outstanding challenges in the study of interrelated networks. We study cascading failures in two interrelated networks S and B composed from dependency chains and connectivity links respectively. This work proposes a realistic model for cascading failures based on the redistribution of traffic flow. We study the Barabasi-Albert networks (BA) and Erdős-Renyi graphs (ER) with such structure and found that the efficiency sharply decreases with increasing percentages of the dependency nodes for removing a node randomly. Furthermore, we study the robustness of interrelated traffic networks, especially the subway and bus network in Beijing. By analyzing different attacking strategies, we uncover that the efficiency of the city traffic system has a non-equilibrium phase transition at low capacity of the networks. This explains why the pressure of the traffic overload is relaxed by singly increasing the number of small buses during rush hours. We also found that the increment of some buses may release traffic jam caused by removing a node of the bus network randomly if the damage is limited. However, the efficiencies to transfer people flow will sharper increase when the capacity of the subway network αS> α0.

62 citations


Journal ArticleDOI
TL;DR: A bus network evolution model to reduce transfer time is proposed by adding lines and the results show that adding lines with nodes of small degree is most effective comparing with the other three types.
Abstract: With the development of the public transportation, bus network becomes complicated and hard to evaluate. Transfer time is a vital indicator to evaluate bus network. This paper proposed a method to calculate transfer times using Space P. Four bus networks in China have been studied in this paper. Some static properties based on graph theory and complex theory are used to evaluate bus topological structure. Moreover, a bus network evolution model to reduce transfer time is proposed by adding lines. The adding method includes four types among nodes with random choice, large transfer time, degree, and small degree. The results show that adding lines with nodes of small degree is most effective comparing with the other three types.

39 citations


Journal ArticleDOI
TL;DR: An interconnected network model considering cascading failures based on the dynamic redistribution of flow in the networks finds that interconnected scale-free networks have higher vulnerability and the network heterogeneity plays an important role in the robustness of interconnected networks under intentional attacks.
Abstract: Cascading failures of loads in isolated networks and coupled networks have been studied in the past few years. In most of the corresponding results, the topologies of the networks are destroyed. Here, we present an interconnected network model considering cascading failures based on the dynamic redistribution of flow in the networks. Compared with the results of single scale-free networks, we find that interconnected scale-free networks have higher vulnerability. Additionally, the network heterogeneity plays an important role in the robustness of interconnected networks under intentional attacks. Considering the effects of various coupling preferences, the results show that there are almost no differences. Finally, the application of our model to the Beijing interconnected traffic network, which consists of a subway network and a bus network, shows that the subway network suffers more damage under the attack. Moreover, the interconnected traffic network may be more exposed to damage after initial attacks on the bus network. These discussions are important for the design and optimization of interconnected networks.

38 citations


Proceedings ArticleDOI
05 Jan 2015
TL;DR: The correlation between the three bus types of G/L/C and some network topology metrics such as node degree distribution and clustering coefficient is examined and the impacts of different bus type assignments on the grid vulnerability to cascading failures are investigated.
Abstract: In order to demonstrate and test new concepts and methods for the future grids, power engineers and researchers need appropriate randomly generated grid network topologies for Monte Carlo experiments. If the random networks are truly representative and if the concepts or methods test well in this environment they would test well on any instance of such a network as the IEEE model systems or other existing grid models. Our previous work [1] proposed a random topology power grid model, called RT-nested-small world, based on the findings from a comprehensive study of the topology and electrical properties of a number of realistic grids. The proposed model can be utilized to generate a large number of power grid test cases with scalable network size featuring the same small-world topology and electrical characteristics found from realistic power grids. On the other hand, we know that dynamics of a grid not only depend on its electrical topology but also on the generation and load settings, and the latter closely relates with an accurate bus type assignment of the grid. Generally speaking, the buses in a power grid test case can be divided into three categories: the generation buses (G), the load buses (L), and the connection buses (C). In [1] our proposed model simply adopts random assignment of bus types in a resulting grid topology, according to the three bus types' ratios. In this paper we examined the correlation between the three bus types of G/L/C and some network topology metrics such as node degree distribution and clustering coefficient. We also investigated the impacts of different bus type assignments on the grid vulnerability to cascading failures using IEEE 300 bus system as an example. We found that (a) the node degree distribution and clustering characteristic are different for different type of buses (G/L/C) in a realistic grid, (b) the changes in bus type assignment in a grid may cause big differences in system dynamics, and (c) the random assignment of bus types in a random topology power grid model should be improved by using a more accurate assignment which is consistent with that of realistic grids.

32 citations


Proceedings ArticleDOI
03 Sep 2015
TL;DR: In this article, a modified IEEE 118 bus network model in accordance with European standards is presented, based on intermitted generation and load time series an appropriate economic dispatch in hourly resolution for a whole year for the conventional generators is calculated.
Abstract: The formulation of a cohesive, yet solvable optimization program for transmission expansion planning of extended systems is engaging many researchers. Related approaches and achievements are often presented by means of a transmission network model with a single snapshot of generation and demand. Moreover the use of proprietary network data leads to difficulties when benchmarking the different existing approaches and thus identifying possible departures to advance. Derived from the IEEE 118 bus network this paper provides a modified network model in accordance with European standards. Four distinct scenarios are developed defining different mixes of conventional and renewable generation facilities as well as the load. Based on intermitted generation and load time series an appropriate economic dispatch in hourly resolution for a whole year for the conventional generators is calculated. Fulfilled by a set of network expansion options the benchmark case including all data is made publicly available.

32 citations


Patent
17 Sep 2015
TL;DR: In this paper, an SVM-based classifier with a Radial Basis Function (RBF) kernel is used to classify a message read from the CAN bus as either normal or anomalous.
Abstract: A security monitoring system for a Controller Area Network (CAN) comprises an Electronic Control Unit (ECU) operatively connected to the CAN bus. The ECU is programmed to classify a message read from the CAN bus as either normal or anomalous using an SVM-based classifier with a Radial Basis Function (RBF) kernel. The classifying includes computing a hyperplane curvature parameter γ of the RBF kernel as γ=ƒ(D) where ƒ( ) denotes a function and D denotes CAN bus message density as a function of time. In some such embodiments γ=ƒ(Var(D)) where Var(D) denotes the variance of the CAN bus message density as a function of time. The security monitoring system may be installed in a vehicle (e.g. automobile, truck, watercraft, aircraft) including a vehicle CAN bus, with the ECU operatively connected to the vehicle CAN bus to read messages communicated on the CAN bus. By not relying on any proprietary knowledge of arbitration IDs from manufacturers through their dbc files, this anomaly detector truly functions as a zero knowledge detector.

30 citations


Book ChapterDOI
01 Jan 2015
TL;DR: This chapter focuses on a specific cyber-physical link, the Automatic Generation Control (AGC), which is an automatic frequency control loop closed over the SCADA system, and provides an impact analysis in case of a cyber-attack on the AGC signal.
Abstract: Power systems are traditionallymonitored and controlled by an IT infrastructure, referred to as Supervisory Control and Data Acquisition (SCADA) system. The cyber-physical interaction of power systems (physical) and SCADA systems (cyber) rises security issues, since the links between those systems are vulnerable to cyber-attacks that can potentially lead to catastrophic economical and societal effects. In this chapter we focus on a specific cyber-physical link, the Automatic Generation Control (AGC), which is an automatic frequency control loop closed over the SCADA system. We provide an impact analysis in case of a cyber-attack on the AGC signal. We first carry out a feasibility analysis based on reachability and optimal control theory, that provides an information regarding the existence of an attack pattern that can disturb the power system. We then deal with the problem of synthesizing an attack signal and treat it as a nonlinear control synthesis problem. Third, performance of our methodologies are illustrated by means of dynamic simulations on IEEE-118 bus network.

Journal ArticleDOI
TL;DR: The work developed the theoretical framework of urban bus network optimization, including optimization principle, optimization objectives and constraints, and showed that the method can better adjust the bus network, and the optimization solution is more reasonable to meet the actual needs.
Abstract: Multi-objective optimization of urban bus network can help improve operation efficiency of the transit system and develop strategies for reducing urban traffic congestion in China. The work used cumulative prospect theory, currently the most influential model for decision under uncertainty, to optimize urban bus network. To achieve the research objective, the work developed the theoretical framework of urban bus network optimization, including optimization principle, optimization objectives and constraints. Furthermore, optimization objectives could comprehensively reflect expectations of passengers and bus companies from the dimension of time, space and value. It is more scientific and reasonable compared with only one stakeholder or dimension alone in the previous studies. In addition, the technique for order preference by similarity to ideal solution (TOPSIS) was used to determine the positive and negative ideal alternative. The correlations between the optimization alternatives and the ideal alternatives were estimated by grey relational analysis simultaneously. The cumulative prospect theory (CPT) was used to determine the best alternative by comparing comprehensive prospect value of every alternative, accurately describing decision-making behavior compared with expected utility theory in actual life. Finally, Case of Xi’an showed that the method can better adjust the bus network, and the optimization solution is more reasonable to meet the actual needs.

Patent
Nirmit Desai1, Ting He1, Liang Ma1
30 Nov 2015
TL;DR: In this paper, a set of predicted network topology snapshot graphs of nodes in the network are generated based on the set of topology prediction models for the network, and a subset of the nodes is selected as monitors in the predicted graph, so that each link in a given set of selected links is identifiable using end-to-end measurements between the monitors.
Abstract: Monitoring a network is provided A set of predicted network topology snapshot graphs of nodes in the network are generated based on a set of network topology prediction models for the network A subset of the nodes is selected as monitors in the set of predicted network topology snapshot graphs of the network so that each link in a set of selected network links is identifiable using end-to-end measurements between the monitors Network states of interest are determined in the set of selected network links within a selected time window based on the end-to-end measurements between the monitors

Patent
20 Jan 2015
TL;DR: In this article, a method implemented on a node connected to a network bus includes: storing one or more message identifiers, the message identifiers comprising at least one message identifier identifying the node, the at least message identifier being included in a message at a time when the message is sent by the node onto the network bus; monitoring network bus traffic, the network buses traffic comprising messages transmitted by both the node and by other nodes connected to the networkbus; and alerting a processor of the node if a message transmitted on the bus by at least 1 of the other nodes is identified as
Abstract: In one embodiment, a method implemented on a node connected to a network bus includes: storing one or more message identifiers, the one or more identifiers comprising at least one message identifier identifying the node, the at least one message identifier being included in a message at a time when the message is sent by the node onto the network bus; monitoring network bus traffic, the network bus traffic comprising messages transmitted by the node and by other nodes connected to the network bus; and alerting a processor of the node if a message transmitted on the network bus by at least one of the other nodes is identified as having a message identifier corresponding to the at least one message identifier.

Journal ArticleDOI
TL;DR: In this article, a shipboard electrical distribution system, a network topology based on the breaker-and-a-half scheme is shown to confer greater reliability than equivalent distribution topologies based on ring bus and double bus, double breaker designs.
Abstract: Distribution system reliability, defined by the expected frequency and duration of load service interruptions caused by component failures, is shown to be dependent on the topology of the distribution network, as well as on the relative placement of loads and generators within the system. In a shipboard electrical distribution system, a network topology based on the breaker-and-a-half scheme is shown to confer greater reliability than equivalent distribution topologies based on the ring bus and double bus, double breaker designs. The overall service interruption rate in the breaker-and-a-half topology is 17.8% less than that in the ring bus topology and 40.0% less than that in the double bus, double breaker topology. Further, an optimized equipment placement configuration is algorithmically identified for the loads and generators within the breaker-and-a-half distribution network, further increasing reliability. The optimal equipment placement decreases the overall system interruption rate by 0.54%. The paper also determines an optimal location for additional in-feeds that should be connected to the ship's most critical loads so that maximum benefits to service reliability are obtained.

Patent
26 May 2015
TL;DR: In this paper, a method for communicating between at least first and second devices over a bus in accordance with a bus address space, including direct access over the bus to a local address space of the first device, is proposed.
Abstract: A method includes communicating between at least first and second devices over a bus in accordance with a bus address space, including providing direct access over the bus to a local address space of the first device by mapping at least some of the addresses of the local address space to the bus address space. In response to indicating, by the first device or the second device, that the second device requires to access a local address in the local address space that is not currently mapped to the bus address space, the local address is mapped to the bus address space, and the local address is accessed directly, by the second device, using the mapping.

Journal ArticleDOI
TL;DR: The methodology developed considers a mechanism to maintain as many satisfactory routes of the existing network as possible and, at the same time, to incorporate experience-based suggestions, such as minimizing of the number of transfers required by a passenger, into the revised bus network.
Abstract: The bus network design problem refers to a determination of optimizing the network of bus routes, usually in urban areas. The optimal routes must comply with a given passenger demand matrix and attain a compromise best solution from the user, the operator, and the community. This paper proposes the use of a genetic algorithm as a tool to handle the complexity of the bus network design problem. The methodology developed considers a mechanism to maintain as many satisfactory routes of the existing network as possible and, at the same time, to incorporate experience-based suggestions, such as minimizing of the number of transfers required by a passenger, into the revised bus network. The solution method, using genetic algorithm, has four steps: (1) generating a set of potential routes, (2) designing the bus network, (3) checking the routes for implementation, and (4) examining the extension of routes for improvement. The proposed method is validated through a benchmark bus network and a case study. T...

Journal ArticleDOI
TL;DR: In this paper, a new measure, journey time buffer index (JTBI), was proposed, which used estimates of wait times at bus stops while capturing variability in wait and travel times that tended to increase the disutility of transit travel.
Abstract: Reliability is cited as a key aspect of service quality, but many of the indicators in use today do not measure reliability from the user’s perspective. A review of earlier work on transit user behavior concluded that the traveler’s perspective of reliability was driven by punctuality in arriving at the destination, short waiting times at the origin stop, and consistent wait and travel times. Twenty indicators were assessed, but none were well suited to capturing all of these elements of reliability. A new measure, journey time buffer index (JTBI), was therefore proposed; the index used estimates of wait times at bus stops while capturing variability in wait and travel times that tended to increase the disutility of transit travel. Alternative formulations were developed for short and long headway service, and the new indicator was applied to the London Transit Commission’s bus network in London, Ontario, Canada. This procedure demonstrated that the JTBI was better suited to identifying the factors contri...

Patent
Shoichiro Sengoku1
12 Jan 2015
TL;DR: In this article, a method for controlling data transmissions over a bus from a master device, where data bits are transcoded into symbols for transmission across two lines of the bus and a clock signal is embedded within symbol transitions of the data transmissions, is presented.
Abstract: Master and slave devices may be coupled to a control data bus. A method includes controlling data transmissions over a bus from a master device, where data bits are transcoded into symbols for transmission across two lines of the bus and a clock signal is embedded within symbol transitions of the data transmissions, and providing an interrupt period, during which one or more slave devices coupled to the bus can assert an interrupt request on a first line of the bus, within part of a heartbeat transmission by the master device over the first line and a second tine of the bus. The interrupt request may be an indicator that the asserting slave device wishes to request some action by the master device.

Proceedings ArticleDOI
03 Sep 2015
TL;DR: A novel measure to characterize typical bus type assignments of realistic power grids, called the Bus Type Entropy, which incorporates both bus type ratios and the link type ratios is defined and proves useful for designing an optimal algorithm to improve random topology power grid modeling.
Abstract: Electric power engineers and researchers need appropriate randomly generated grid network topologies for Monte Carlo experiments to test and demonstrate new concepts and methods Our previous work proposed a random topology power grid model, called RT-nested-smallworld, based on a comprehensive study of the real-world grid topologies and electrical properties The proposed model can be used to produce a sufficiently large number of power grid test cases with scalable network size featuring the same kind of small-world topology and electrical characteristics found in realistic grids However, the proposed RT-power grid model has a shortcoming that is its random assignment of bus types And our recent study has shown that the bus type assignment of a realistic power grid is not random but a correlated one Generally speaking, the buses in a power grid can be grouped into three categories: generation buses (G), load buses (L), and connection buses (C) When studying the dynamics of a grid we need to take into account not only its “electrical” topology but also the generation and load settings including their locations, which are equivalent to the bus type assignments in our model

Journal ArticleDOI
TL;DR: In this article, the reliability measures of Linux operating system connected in local area network (LAN) have been found by using supplementary variable technique and Laplace transformation, by taking different types of failure and two types of repairs the availability, non-availability, mean time to failure and cost analysis (expected profit) of the design system have been obtained.
Abstract: Purpose – The purpose of this paper is to find the reliability measures of Linux operating system connected in local area network (LAN). Design/methodology/approach – The system has two different topologies, i.e. star topology (subsystem-1) and bus topology (subsystem-2), are placed at two different places, and connected to a server through a hub. Both the topologies have n clients. The system has partial failure and complete failure. The partial failure is of two type’s namely minor partial and major partial. The minor partial failure degrades the system whereas the major partial failure brings the system to a break down mode. The system can completely fail due to failure of server hacking and blocking. Findings – By using supplementary variable technique and Laplace transformation, by taking different types of failure and two types of repairs the availability, non-availability, mean time to failure and cost analysis (expected profit) of the design system have been obtained. Originality/value – In this r...

Patent
24 Jun 2015
TL;DR: In this paper, a power-driven six-degree of freedom motion platform high-precision control system and control method has been presented, which has the advantages of being high in control real-time performance, good in motion synchronism of all branches, high in reliability, simple in structure, flexible in extension and easy to maintain.
Abstract: The invention belongs to the technical field of mechanical-electrical integration and drive control and discloses a power-driven six-degree of freedom motion platform high-precision control system and control method. The power-driven six-degree of freedom motion platform high-precision control system comprises an embedded controller, a real-time Ethernet bus network and a driver; the embedded controller transfers a control instruction to the driver through the real-time Ethernet bus network, a power-driven cylinder is connected with a servo motor, the driver drives the servo motor directly, the servo motor drives the power-driven cylinder to perform telescopic motion, and the motion of a six degrees of freedom motion platform is achieved. The power-driven six-degree of freedom motion platform high-precision control system and control method have the advantages of being high in control real-time performance, good in motion synchronism of all branches, high in reliability, simple in structure, flexible in extension and easy to maintain. Based on the flexible software design platform, not only can the motion simulation be achieved, but also the high-precision multi-degree of freedom location can be achieved.

Journal ArticleDOI
Jiaqing Wu, Rui Song, Youan Wang1, Feng Chen, Shubin Li 
TL;DR: In this paper, a coordinated operation model of bus rapid transit and feeder bus service is developed to improve the operational efficiency and service level of urban public transport system, and the total costs are formulated and optimized by genetic algorithm.
Abstract: The coordination between bus rapid transit (BRT) and feeder bus service is helpful in improving the operational efficiency and service level of urban public transport system. Therefore, a coordinated operation model of BRT and bus is intended to develop in this paper. The total costs are formulated and optimized by genetic algorithm. Moreover, the skip-stop BRT operation is considered when building the coordinated operation model. A case of the existing bus network in Beijing is studied, the proposed coordinated operation model of BRT and bus is applied, and the optimized headway and costs are obtained. The results show that the coordinated operation model could effectively decrease the total costs of the transit system and the transfer time of passengers. The results also suggest that the coordination between the skip-stop BRT and bus during peak hour is more effective than non-coordination operation.

Patent
22 May 2015
TL;DR: In this article, a detection control routine for detecting the presence of wire-open fault on the CAN bus, including determining a CAN bus resistance, and determining a wire-Open Fault Detection System (WODDS) based on the determined CAN bus bus resistance and the terminator resistance values.
Abstract: A controller area network (CAN) includes a CAN bus with a CAN-H wire, a CAN-L wire, a pair of CAN bus terminators located at opposite ends of the CAN bus, each terminator having a corresponding known terminator resistance value, a plurality of nodes including controllers wherein at least one of said controllers is a monitoring controller. The monitoring controller includes a detection control routine for detecting the presence of a wire-open fault on the CAN bus, including determining a CAN bus resistance, and determining a wire-open fault on the CAN bus based upon the determined CAN bus resistance and the terminator resistance values.

Journal ArticleDOI
TL;DR: A comparison with the traditional sequential modeling framework indicates that the proposed approach has a better performance and is more robust than the traditional approach, and the practical applicability of the approach is proved by employing a real size network.
Abstract: The traditional manner to design public transportation system is to sequentially design the transit network and public bicycle network. A new public transportation system design problem that simultaneously considers both bus network design and public bicycle network design is proposed. The chemical reaction optimization (CRO) is designed to solve the problem. A shortcoming of CRO is that, when the two-molecule collisions take place, the molecules are randomly picked from the container. Hence, we improve CRO by employing different mating strategies. The computational results confirm the benefits of the mating strategies. Numerical experiments are conducted on the Sioux-Falls network. A comparison with the traditional sequential modeling framework indicates that the proposed approach has a better performance and is more robust. The practical applicability of the approach is proved by employing a real size network.

Patent
16 Mar 2015
TL;DR: In this paper, a bus interface system with a master bus controller and a slave bus controller coupled to the bus line is described, where the master bus is configured to generate a sequence of data pulses along a bus line such that the sequence of pulses is provided in accordance with a start of sequence (SOS) pulse pattern.
Abstract: The disclosure relates to bus interface systems. In one embodiment, the bus interface system includes a bus line along with a master bus controller and a slave bus controller coupled to the bus line. In order to start a data frame, the master bus controller is configured to generate a sequence of data pulses along the bus line such that the sequence of data pulses is provided in accordance to a start of sequence (SOS) pulse pattern. The slave bus controller is configured to recognize that the sequence of data transmitted along the bus line by the master bus controller has been provided in accordance with the SOS pulse pattern. In this manner, the slave bus controller can detect when the master bus controller has started a new data frame. As such, the exchange of information through data frames can be synchronized along the bus line with requiring an additional bus line for a clock signal.

Patent
16 Mar 2015
TL;DR: In this article, a bus interface system includes a master bus controller and multiple slave bus controllers that are coupled to a bus line, each of which decodes the first set of data pulses along the bus line representing the payload segment and performs an error check.
Abstract: Embodiments of bus interface systems and methods of operating the same are disclosed. In one embodiment, a bus interface system includes a master bus controller and multiple slave bus controllers that are each coupled to a bus line. The master bus controller is configured to generate a first set of data pulses along the bus line representing a payload segment. Each of the slave bus controllers decodes the first set of data pulses along the bus line representing the payload segment and performs an error check. Each slave bus controller is then configured to generate an acknowledgement pulse along the bus line to indicate that the slave bus controller's particular error check was passed. In this manner, the bus interface system can perform a group write bus function and the master bus controller can determine that the multiple slave bus controllers each received an accurate copy of the payload segment.

Proceedings ArticleDOI
01 Oct 2015
TL;DR: This work proposes to exploit the built-in CAN fault confinement mechanism to detect the masquerade attacks originated from the malicious CAN devices on the CAN bus and reduces the encryption latency by up to 68% over the complete frame encryption method.
Abstract: Controller Area Network (CAN) is the main bus network that connects electronic control units in automobiles. Although CAN protocols have been revised to improve the vehicle safety, the security weaknesses of CAN have not been fully addressed. Security threats on automobiles might be from external wireless communication or from internal malicious CAN nodes mounted on the CAN bus. Despite of various threat sources, the security weakness of CAN is the root of security problems. Due to the limited computation power and storage capacity on each CAN node, there is a lack of hardware-efficient protection methods for the CAN system without losing the compatibility to CAN protocols. To save the cost and maintain the compatibility, we propose to exploit the built-in CAN fault confinement mechanism to detect the masquerade attacks originated from the malicious CAN devices on the CAN bus. Simulation results show that our method achieves the attack misdetection rate at the order of 10-5 and reduces the encryption latency by up to 68% over the complete frame encryption method.

Patent
15 Oct 2015
TL;DR: In this paper, a controller is connected to first and last ones of the power supplies by the serial bus, and the controller transmits status information of the plurality of power supplies to a management bus via the management bus interface of the controller.
Abstract: A system includes a plurality of power supplies and a controller. The plurality of power supplies outputs power to a load. A serial bus connects the plurality of power supplies in a daisy chain. The controller is connected to first and last ones of the power supplies by the serial bus. The controller is connected to a management bus via a management bus interface. The controller monitors the plurality of power supplies via the serial bus. The controller transmits status information of the plurality of power supplies to the management bus via the management bus interface of the controller.

Proceedings ArticleDOI
26 Aug 2015
TL;DR: This work proposes the Difference-Overloaded CDMA Interconnect (D-OCI) bus that leverages the balancing property of the Walsh codes to increase the number of interconnected elements by 50% and motivates using Code Division Multiple Access (CDMA) as a bus sharing strategy which offers many advantages over other topologies.
Abstract: On-chip interconnect is a major building block and a main performance bottleneck in modern complex System-on-Chips (SoCs). The bus topology and its derivatives are the most deployed communication architectures in contemporary SoCs. Space switching exemplified by cross bars and multiplexers, and time sharing are the key enablers of various bus architectures. The cross bar has quadratic complexity while resource sharing significantly degrades the overall system's performance. In this work we motivate using Code Division Multiple Access (CDMA) as a bus sharing strategy which offers many advantages over other topologies. Our work seeks to complement the conventional CDMA bus features by applying overloaded CDMA practices to increase the bus utilization efficiency. We propose the Difference-Overloaded CDMA Interconnect (D-OCI) bus that leverages the balancing property of the Walsh codes to increase the number of interconnected elements by 50%. Two implementations of the D-OCI bus optimized for both speed and resource utilization are presented. The bus operation is validated on a Xilinx Artix-7 AC701 FPGA kit and the bus performance is evaluated and compared to other existing bus topologies. We also present the synthesis results for the UMC-0.13 a#x03BC;m design kit to give an idea of the maximum achievable bus frequency on ASIC platforms. Moreover, we advance a proof-of-concept HLS implementation of the D-OCI bus on a Xilinx Zynq-7000 SoC and compare its performance, latency, and resource utilization to the ARM AXI bus. The performance evaluation demonstrates the superiority of the D-OCI bus.