Showing papers in "IEEE Systems Journal in 2011"
TL;DR: This paper proposes new network resilience metrics that reflect the heterogeneous roles of nodes in supply networks and presents a hybrid and tunable network growth model called Degree and Locality-based Attachment (DLA), in which new nodes make connections based on both degree and locality.
Abstract: In this paper, we study the resilience of supply networks against disruptions and provide insights to supply chain managers on how to construct a resilient supply network from the perspective of complex network topologies. Our goal is to study how different network topologies, which are created from different growth models, affect the network's resilience against both random and targeted disruptions. Of particular interest are situations where the type of disruption is unknown. Using a military logistic network as a case study, we propose new network resilience metrics that reflect the heterogeneous roles (e.g., supply, relay, and demand) of nodes in supply networks. We also present a hybrid and tunable network growth model called Degree and Locality-based Attachment (DLA), in which new nodes make connections based on both degree and locality. Using computer simulations, we compare the resilience of several supply network topologies that are generated with different growth models. The results show that the new resilience metrics can capture important resilience requirements for supply networks very well. We also found that the supply network topology generated by the DLA model provides balanced resilience against both random and targeted disruptions.
239 citations
TL;DR: The resilience and friability of the railway network within the Chinese mainland is evaluated and analyzed, and a structure optimization model with a computational algorithm for transportation network design is recommended.
Abstract: To analyze the resilience of transportation networks, it is proposed to use a quantifiable resilience evaluation approach. First, we represent transportation networks by an undirected graph with the nodes as cities and edges as traffic roads. Because the survivability of transportation of a pair of cities depends on the number of passageways between them, the resilience of a city node can be evaluated by the weighted average number of reliable passageways with all other city nodes in the network. The network resilience can then be calculated by the weighted sum of the resilience of all nodes. To identify critical road lines or hub cities in networks, the concept of friability is proposed. This is defined as the reduction in total resilience upon removing an edge or hub city. Following the resilience and friability evaluation, a structure optimization model with a computational algorithm for transportation network design is recommended. Based on the recommended approaches, the resilience and friability of the railway network within the Chinese mainland is evaluated and analyzed. Several interesting conclusions are drawn from the computational results. The friability value of the railway lines in the Sichuan Basin which was damaged by the recent earthquake in China was also calculated.
205 citations
TL;DR: An adaptive proportional-integral-derivative (APID) control system to deal with the metallic sphere position control of a magnetic levitation system (MLS), which is an intricate and highly nonlinear system.
Abstract: This paper develops an adaptive proportional-integral-derivative (APID) control system to deal with the metallic sphere position control of a magnetic levitation system (MLS), which is an intricate and highly nonlinear system. The proposed control system consists of an adaptive PID controller and a fuzzy compensation controller. The adaptive PID controller is a main tracking controller, and the parameters of the adaptive PID controller are online tuned by the derived adaptation laws. In this design, the particle swarm optimization (PSO) technology is adopted to search the optimal learning-rates of the adaptive PID controller to increase the learning speed. The design of the fuzzy compensation controller can guarantee the stability of the control system. Since system-on-programmable-chip (SoPC) has several benefits including low cost, high speed, and small volume, the developed control scheme is implemented in the SoPC-based hardware. Finally, simulation and experimental results of the magnetic levitation system have been performed to verify the effectiveness of the proposed control scheme.
86 citations
TL;DR: This paper focuses on the investigation of existing simulator models applicable in forecasting forest fire propagation and concludes with the FARSITE simulator model which is the one that stands out from the rest, and for this reason, it is investigated in depth and evaluated in a test environment.
Abstract: Phenomena in ecosystems such as forest fires, oil spills, tornados, etc., are complex processes both in time and space. Understanding their dynamics in order to predict their future states is a challenging procedure involving the propagation of several events concerning, e.g., the transfer of energy or material. A common solution used to study such phenomena is the utilization of discrete event models and simulators. Among the phenomena studied by researchers so far, of particular interest and importance, is the forecasting of forest fire propagation since life on earth is greatly dependent on healthy forests. This paper is focused on the investigation of existing simulator models applicable in forecasting forest fire propagation. Twenty-three simulators were found in the literature and are presented here. The comparison discussion concludes with the FARSITE simulator model which is the one that stands out from the rest, and for this reason, it is investigated in depth and evaluated in a test environment.
83 citations
TL;DR: A QoS trust estimation model based on social network analysis is designed, which enables each sensor node measuring the service quality by monitoring the behaviors of neighbor nodes, and shows the high performance of EEQAR routing in lifetime and quality of service.
Abstract: As a new multimedia information acquisition and processing method, wireless multimedia sensor network (WMSN) has great application potential and attracts more and more attentions. Compared to traditional wireless sensor networks, the routing design of WMSN has higher requirements on the quality of service (QoS). This paper systemically analyzes the similarity between social network and WMSN, then designs a QoS trust estimation model based on social network analysis, which enables each sensor node measuring the service quality by monitoring the behaviors of neighbor nodes. An energy efficient QoS assurance routing based on cluster hierarchy (EEQAR) is proposed to achieve energy efficiency and meet the requirement of QoS. To obtain a better performance, EEQAR routing adopts cellular topology to form the cluster structure and balance the energy consumption by structure movement. The simulation results show the high performance of EEQAR routing in lifetime and quality of service.
72 citations
TL;DR: The design of both next-generation network (NGN)-based and non-NGN-based architectures that have been recently proposed to enable the deployment of IPTV are presented and the challenges and solutions associated with mobile IPTV and peer-to-peer IPTV systems are described.
Abstract: Internet protocol television (IPTV), a technology that delivers video content over a network that uses the IP networking protocol, has been receiving a lot of attention over the last couple of years. The increasing interest in IPTV is being driven by remarkable advances in digital technologies and consumer electronic devices, broadband networking technologies, Web services, as well as more entertainment demands (enabled by decreasing costs of hardware and software technologies) from both consumers and content providers. In this paper, we briefly discuss IPTV standardization initiatives and present the design of both next-generation network (NGN)-based and non-NGN-based architectures that have been recently proposed to enable the deployment of IPTV. In addition, we describe the challenges and solutions associated with mobile IPTV and peer-to-peer IPTV systems. We Anally present some IPTV trends and identify some of the IPTV challenges that must be addressed to enable the ubiquitous deployment and adoption of IPTV.
72 citations
TL;DR: Friend based Ad hoc routing using Challenges to Establish Security (FACES) is an algorithm to provide secure routing in ad hoc mobile networks and provides an efficient approach towards security and easier detection of malicious nodes in the mobile ad hoc network.
Abstract: Friend based Ad hoc routing using Challenges to Establish Security (FACES) is an algorithm to provide secure routing in ad hoc mobile networks We propose this scheme that has been drawn from a network of friends in real life scenarios The algorithm works by sending challenges and sharing friend Lists to provide a list of trusted nodes to the source node through which data transmission finally takes place The nodes in the friend list are rated on the basis of the amount of data transmission they accomplish and their friendship with other nodes in the network The account of friendship of a node with other nodes in the network is obtained through the Share Your Friends process which is a periodic event in the network As a result of this scheme of operation, the network is able to effectively isolate the malicious nodes which are left with no role to play in the ad hoc network One major benefit of this scheme is that the nodes do not need to promiscuously listen to the traffic passing through their neighbors The information about the malicious nodes is gathered effectively by using Challenges This reduces the overhead on the network significantly Through extensive simulation analysis it was inferred that this scheme provides an efficient approach towards security and easier detection of malicious nodes in the mobile ad hoc network
72 citations
TL;DR: A Cloud perspective on supply chain systems is proposed to represent supply chains as a set of service offerings and customer demand as service requests; coordination is then a problem of determining optimal service compositions.
Abstract: Supply chains are characterized by multiple firms providing their resources and processes to meeting customer demand in an efficient manner. There exists a great variety of approaches for solving the inherent coordination problem. It has been acknowledged that the autonomy of supply chain participants - and their business objectives - as well as the contractual relations between participants have to be maintained when designing a coordination mechanism. Often, new mechanisms are triggered by innovation in the software industry. This paper adopts the basic idea of Cloud Computing and takes a Cloud perspective on supply chain systems: It proposes to represent supply chains as a set of service offerings and customer demand as service requests; coordination is then a problem of determining optimal service compositions. We evaluate our proposal in a case study of airport service supply chains.
67 citations
TL;DR: The proposed system-of-systems-based analysis framework (called Innovation System of Systems) would resolve the methodological challenges that System of Innovation studies are confronting in developing theoretical frameworks and is capable of being tested by other researchers in the area of Systems of Innovation to advance the state of knowledge.
Abstract: The objective of this paper is to propose an analysis framework based on the System of Systems approach to overcome existing methodological problems in System of Innovation studies. The concept of System of Innovation has been an important focus of innovation policy studies over the last decade. These studies have concentrated on structuring theoretical frameworks to assess the determinants of innovation processes using systems analysis principles. Despite about 20 years of research, System of Innovation has yet to become a theoretical framework. This paper reviews the relevant literature in an attempt to identify the challenges that System of Innovation studies face in structuring theoretical frameworks. The primary reason for the challenges appears to be that Systems of Innovation have been analyzed as monolithic systems when, in reality, Systems of Innovation are Systems of Systems, which have different features than monolithic systems. Different dimensions of assessment of System of Systems analysis are therefore required in System of Innovation studies. Three dimensions of System of Innovation analysis (definition, abstraction, and modeling) are introduced here to provide an analysis framework for Systems of Innovation studies. The proposed system-of-systems-based analysis framework (called Innovation System of Systems) would resolve the methodological challenges that System of Innovation studies are confronting in developing theoretical frameworks. Thus, it is capable of being tested by other researchers in the area of Systems of Innovation to advance the state of knowledge.
63 citations
TL;DR: A new fingerprint recognition scheme based on a set of assembled invariant moment (geometric moment and Zernike moment) features to ensure the secure communications is proposed and the experimental results show that the proposed method has a higher matching accuracy comparing with traditional or individual feature based methods on public databases.
Abstract: In cloud computing communications, information security entails the protection of information elements (e.g., multimedia data), only authorized users are allowed to access the available contents. Fingerprint recognition is one of the popular and effective approaches for priori authorizing the users and protecting the information elements during the communications. However, traditional fingerprint recognition approaches have demerits of easy losing rich information and poor performances due to the complex inputs, such as image rotation, incomplete input image, poor quality image enrollment, and so on. In order to overcome these shortcomings, in this paper, a new fingerprint recognition scheme based on a set of assembled invariant moment (geometric moment and Zernike moment) features to ensure the secure communications is proposed. And the proposed scheme is also based on an effective preprocessing, the extraction of local and global features and a powerful classification tool, thus it is able to handle the various input conditions encountered in the cloud computing communication. The experimental results show that the proposed method has a higher matching accuracy comparing with traditional or individual feature based methods on public databases.
61 citations
TL;DR: An anticipative system which operates during pedestrian evacuation processes and prevents escape points from congestion and is based on Cellular Automata, thus taking advantage of their inherent ability to represent effectively phenomena of arbitrary complexity.
Abstract: This paper presents an anticipative system which operates during pedestrian evacuation processes and prevents escape points from congestion. The processing framework of the system includes four discrete stages: a) the detection and tracking of pedestrians, b) the estimation of possible route for the very near future, indicating possible congestion in exits, c) the proposal of free and nearby escape alternatives, and d) the activation of guiding signals, sound and optical. Detection and tracking of pedestrians is based on an enhanced implementation of a system proposed by Viola, Jones, and Snow that incorporates both appearance and motion information in near real-time. At any moment, detected pedestrians can instantly be defined as the initial condition of the second stage of the system, i.e., the route estimation model. Route estimation is enabled by a dynamic model inspired by electrostatic-induced potential fields. The model combines electrostatic-induced potential fields to incorporate flexibility in the movement of pedestrians. It is based on Cellular Automata (CA), thus taking advantage of their inherent ability to represent effectively phenomena of arbitrary complexity. Presumable congestion during crowd egress, leads to the prompt activation of sound and optical signals that guide pedestrians towards alternative escaping points. Anticipative crowd management has not been thoroughly employed and this system aims at constituting an effective proposal.
TL;DR: It is shown that an irreversible method is very likely a VQ-based data-hiding method that produces a stego-image as its output, and it can embed more secret data than a reversible method.
Abstract: Data hiding is one of the most important techniques to achieve better data and communication protection by hiding information into a media carrier. It provides a secure method to distribute data through a public and open channel. Data hiding for vector quantization (VQ)-based images focuses on the problem of embedding secret data into a cover VQ-based image to achieve secret communication and data protection. This paper provides a state-of-the-art review and comparison of the different existing data-hiding methods for VQ-based images. In this paper, we classify VQ-based data-hiding methods into four nonoverlapping groups according to their reversibility and output formats, introduce the details of the representative methods, summarize the features of the representative methods, and compare the performance of the representative methods using peak signal-to-noise ratio, capacity of secret data, and bit rate. Our paper shows that an irreversible method is very likely a VQ-based data-hiding method that produces a stego-image as its output, and it can embed more secret data than a reversible method. Nonstandard encoding methods (e.g., joint neighboring coding) are becoming popular in reversible data hiding since they can increase the capacity for embedding the secret data. Some methods with high compression rate, such as the search order coding-based methods, may reduce the compression rate in return for the capacity for the secret data.
TL;DR: This paper proposes using Extended Fuzzy Cognitive Maps (E-FCMs) to analyze the relationships between risk factors and risks, and adopting a pessimistic approach to assess the overall risk of a system or a project.
Abstract: One of the challenges in Risk Analysis and Management (RAM) is identifying the relationships between risk factors and risks. The complexity of the method to analyze these relationships, the time to complete the analysis, the robustness and trustworthiness of the method are important features to be considered. In this paper, we propose using Extended Fuzzy Cognitive Maps (E-FCMs) to analyze the relationships between risk factors and risks, and adopting a pessimistic approach to assess the overall risk of a system or a project. E-FCMs are suggested by Hagiwara to represent causal relationships more naturally. The main differences between E-FCMs and conventional Fuzzy Cognitive Maps (FCMs) are the following: E-FCMs have nonlinear membership functions, conditional weights, and time delay weights. Therefore E-FCMs are suitable for risk analysis as all features of E-FCMs are more informative and can fit the needs of Risk Analysis. In this paper we suggest a framework to analyze risks using E-FCMs and extend E-FCMs themselves by introducing a special graphical representation for risk analysis. We also suggest a framework for group decision making using E-FCMs. Particularly, we explore the Software Project Management (SPM) and discuss risk analysis of SPM applying E-FCMs.
TL;DR: The favor weak FLS can increase the probability of threat detection, and provides timely indication & warning (I&W) and it shows that the favor weak fuzzy logic system has clear advantage comparing to the type-1 FLS.
Abstract: Humans use multiple sources of sensory information to estimate environmental properties and has innate ability to integrate information from heterogeneous data sources. How the multi-sensory and multimodal information are integrated in human brain? There is consensus that it depends on the prefrontal cortex (PFC). The PFC has top-down control (favor weak) and rule-based mechanisms, and we propose to incorporate the favor weak mechanism into rule-based fuzzy logic systems (FLS) via using upper and lower membership functions. The inference engine of favor weak fuzzy logic system is proposed under three different categories based on fuzzifiers. We observe that the favor weak FLS is a special type-1 FLS which is embeded in an interval type-2 FLS, so it's much simpler in computing than an interval type-2 FLS. We apply the favor weak FLS to situation understanding based on heterogeneous sensor network, and it shows that our favor weak fuzzy logic system has clear advantage comparing to the type-1 FLS. The favor weak FLS can increase the probability of threat detection, and provides timely indication & warning (I&W).
TL;DR: A new set of analytical and experimental results are presented to demonstrate that the proposed stochastic authentication approach achieves a low half total error rate in ECG signals verification.
Abstract: The blood circulation system in a human body provides a unique and natural trust zone for secure data communications in wireless healthcare systems such as body area networks. Unfortunately, biometric signal authentication using physiological attributes in wireless healthcare has not been extensively studied. In this paper, we propose a data authentication approach utilizing electrocardiography (ECG) signal patterns for reducing key exchange overhead. The major contribution of this research is to apply stochastic pattern recognition techniques in wireless healthcare. In the proposed approach, the inter-pulse interval (IPI) signal pattern at transmitter side is summarized as a biometric authentication key using Gaussian mixture model (GMM). At the receiver side, a light-weight signature verification scheme is adopted that uses IPI signals gathered locally at the receiver. The proposed authentication scheme has the advantage of high sample misalignment tolerance. In our earlier work, we had demonstrated the concept of stochastic authentication for ECG signal, but the signature verification process and GMM authentication performance under time synchronization and various sample points were not discussed. Here, we present a new set of analytical and experimental results to demonstrate that the proposed stochastic authentication approach achieves a low half total error rate in ECG signals verification.
TL;DR: The architecture and implementation of an automatic medication dispenser for users who take medications without close professional supervision is presented, which makes the user's medication schedule easy to adhere and tolerant to tardiness whenever possible.
Abstract: This paper presents the architecture and implementation of an automatic medication dispenser for users who take medications without close professional supervision. By relieving the user from the error-prone tasks of interpreting medication directions and administrating medications accordingly, the device can improve the rigor in compliance and prevent serious medication errors. By taking advantage of scheduling flexibility provided by medication directions, the device makes the user's medication schedule easy to adhere and tolerant to tardiness whenever possible. The medication scheduler and dispenser controller do this work collaboratively in an action-oriented manner. An advantage of this design is that new functions can be added and existing ones removed or revised with little or no need to modify the dispenser control structure.
TL;DR: A simple and lightweight mechanism for NEMO within Proxy Mobile IPv6 (PMIPv6), which is a network-based mobility management protocol, is introduced and enables a moving network to change its point of attachment at a given PMIPv 6 domain without acquiring a new address and sending its own mobility signaling.
Abstract: NEtwork MObility (NEMO) provides that a moving network involving mobile network nodes (MNNs) can move around the Internet without loss of connection. NEMO Basic Support (NBS) has been developed as an extension of Mobile IPv6 (MIPv6) so that it succeeds to drawbacks of host-based mobility management protocol. In NBS, the moving network keeps its connectivity with its home agent (HA) through its registration procedure. In other words, the moving network is required to obtain its new address and to send its own mobility signaling to the HA for every movements. In this paper, a simple and lightweight mechanism for NEMO within Proxy Mobile IPv6 (PMIPv6), which is a network-based mobility management protocol, is introduced. The proposed mechanism enables a moving network to change its point of attachment at a given PMIPv6 domain without acquiring a new address and sending its own mobility signaling. Mobility service provisioning entities residing at the PMIPv6 domain are extended to support NEMO. The analytical performance analysis is conducted to demonstrate that the moving network in the proposed mechanism achieves the reduced traffic cost and handover latency compared to NBS.
TL;DR: The experimental results show that the MHS can improve the medication adherence of the elderly effectively and provides the continuous medication monitoring, context aware prompting, adaptive multimedia presentation, and flexible medicine management.
Abstract: Due to its proven capability in customizing information according to the patients' needs, multimedia has been regarded as a promising technology for home healthcare. In this paper, we present our study on improving medication adherence of the elderly with the support of ubiquitous multimedia services. A multimedia healthcare system (MHS) is built based on a comprehensive understanding of the requirements of the elderly care. It provides the continuous medication monitoring, context aware prompting, adaptive multimedia presentation, and flexible medicine management. The experimental results show that the MHS can improve the medication adherence of the elderly effectively.
TL;DR: This paper provides thirty one heuristics that have been inspired by the development and application of a systems engineering cost estimation model that can benefit systems engineering researchers and practitioners that develop, calibrate, and use cost models.
Abstract: Engineering cannot wait until all phenomena are explained. Engineers may work effectively, often for centuries, with heuristics. This paper provides thirty one heuristics that have been inspired by the development and application of a systems engineering cost estimation model. The objective of this paper is to present such heuristics in a simple manner so that they can benefit systems engineering researchers and practitioners that develop, calibrate, and use cost models.
TL;DR: An adaptive neural network, designed to improve the performance of conventional automatic landing systems (ALS), was applied to train the neural network using the gradient-descent of an error function to adaptively update weights.
Abstract: This paper presents an adaptive neural network, designed to improve the performance of conventional automatic landing systems (ALS). Real-time learning was applied to train the neural network using the gradient-descent of an error function to adaptively update weights. Adaptive learning rates were obtained through the analysis of Lyapunov stability to guarantee the convergence of learning. In addition, we applied a DSP controller using the VisSim/TI C2000 Rapid Prototyper to develop an embedded control system and establish on-line real-time control. Simulations show that the proposed control scheme has superior performance to conventional ALS under conditions of wind disturbance of up to 75 ft/s.
TL;DR: An adaptive scheme for estimating the trip boundaries of a distance relay in presence of a Unified Power Flow Controller (UPFC), utilizing a Generalized Regression Neural Network (GRNN).
Abstract: The operation of Flexible AC Transmission System Controllers (FACTS) in the power transmission system pose a challenge to the distance relaying scheme. This paper suggests an adaptive scheme for estimating the trip boundaries of a distance relay in presence of a Unified Power Flow Controller (UPFC), utilizing a Generalized Regression Neural Network (GRNN). Initially, the impact of the UPFC on the relay's trip boundary is studied for its automatic power flow control mode as well as bypass mode of operation. The GRNN has been trained off-line with the data generated from a detailed performance analysis of the power system for various faults considering the effects of the UPFC, fault resistance, and system loading conditions on the trip boundaries. This work has also proposed a strategy that computes the control parameters of the UPFC on-line, namely, series voltage and reactive current injections, utilizing the synchronized phasor measurements from Phasor Measurement Units (PMUs). Pre-fault system states, including the control parameters of the UPFC and the apparent impedance measured by the relay unit have been utilized by the GRNN for predicting the trip boundaries of the relay. The proposed scheme has considered Single Line-to-Ground (SLG), Double Line-to-Ground (LLG) and Three Phase-to-Ground (LLLG) faults and the effectiveness of the scheme has been tested on 39-bus New England system and also on a 17-bus system, a reduced equivalent of practical Northern Regional Power Grid (NRPG) system in India.
TL;DR: This paper regards the world of complexity factors as an abstract system and proposes a new framework consisting of five views, each of which is concerned with certain aspects of the abstract system, and describes two possible uses of the framework and the complexity factor model.
Abstract: As the nature of human interaction with modernized socio-technical systems is increasingly cognitive and complex, many studies have been devoted to examine a range of complexity factors influencing human cognitive performance. However, there is a lack of theoretical basis of discerning and categorizing those factors. It is thus inevitable to establish a conceptual framework that can be used to identify and organize the complexity factors in an analytical way. In this paper, we regard the world of complexity factors as an abstract system and propose a new framework consisting of five views, each of which is concerned with certain aspects of the abstract system. To develop the framework more systematically, we conducted a comprehensive literature review and applied a system thinking approach to deriving a set of requirements to be satisfied by the framework. Of those five views, we particularly emphasize the roles of knowledge view. Thus a complexity factor model based on the knowledge view is also proposed. We describe two possible uses of the framework and the complexity factor model, which are the analytical identification of the complexity factors and the systematic assessment of the complexity factors identified by earlier studies.
TL;DR: The forward-looking forward error correction (FL-FEC) mechanism is proposed to recover lost packets for video streaming over wireless networks and is tested to show the benefits of high recovery performance and low recovery overhead in improving the peak signal-to-noise ratio and the decodable frame rate of video streamingover wireless networks.
Abstract: Video streaming over wireless network poses a great challenge because the high packet error rate usually decreases the quality of video streaming. Forward error correction (FEC) mechanism is generally used to protect the video quality. However, the recovery performance of the FEC mechanism decreases when burst packet loss is larger than the added FEC redundant packets. In this paper, the forward-looking forward error correction (FL-FEC) mechanism is proposed to recover lost packets for video streaming over wireless networks. The FL-FEC mechanism recovers not only the lost packet from its FEC block but also the previous FEC block from the recovered packet, repeating the recovery procedure until recovering the first FEC block. If the play-out buffer at the receiver is large, the FL-FEC mechanism can execute a chain of recovery procedures to ultimately recover all lost packets without any negative impact on application performance. The FL-FEC mechanism selects non-continuous source packets in previous FEC blocks to generate FEC redundancy with the FEC block. Hence, the FL-FEC mechanism can significantly disperse burst packet loss into different FEC blocks. The FL-FEC mechanism uses an analytical model to decide the number of FEC redundant packets in order to obtain the minimum recovery overhead. The FL-FEC mechanism is tested to show the benefits of high recovery performance and low recovery overhead in improving the peak signal-to-noise ratio and the decodable frame rate of video streaming over wireless networks.
TL;DR: A new technique named interpolation-based direction-adaptive lifting DWT, which can adaptively choose the best lifting direction and use the Lagrange interpolation technique to make prediction according to its local characteristics, which makes good use of the image texture features.
Abstract: Image compression, as one of the key-enabling technologies in multimedia communications, has been paid much attention in the past decades, where the two key techniques discrete wavelet transform (DWT) and set-partitioning in hierarchical trees (SPIHT) have great influence on its final performance. Due to the proprieties of fast computation, low memory requirement, DWT has been adopted as a new technical standard for still image compression. But it did not make much use of the region information. Although several improved methods have been proposed that adopt direction-adaptive wavelet for using the geometric and spatial information, they still did not consider the texture information. Furthermore, the traditional SPIHT algorithm has the drawbacks of long bits output and time consuming. In this paper, we first propose a new technique named interpolation-based direction-adaptive lifting DWT. It can adaptively choose the best lifting direction and use the Lagrange interpolation technique to make prediction according to its local characteristics. This method makes good use of the image texture features. Then a modified SPIHT coding algorithm is presented. It improves the scanning process and can effectively reduce the coding bits length and running time. Experimental results demonstrate that our method can yield better results than traditional techniques.
TL;DR: A self correcting multi-agent architecture for the supply chain for the distributed manufacturing environment that focuses on automatic selection of best techniques and suppliers while making the tradeoff between the cost, availability, reliability, distance and quality of the products supplied.
Abstract: Nowadays the supply chain for distributed manufacturing is gaining attention of the researchers worldwide. Realizing its significance this article proposes a self correcting multi-agent architecture for the supply chain for the distributed manufacturing environment. The main aim of the proposed architecture is to generate an effective manufacturing plan while exploring the algorithm portfolio concept to minimize the manufacturing and supply chain costs. This architecture focuses on automatic selection of best techniques and suppliers while making the tradeoff between the cost, availability, reliability, distance and quality of the products supplied. When the new order arrives, the proposed architecture explores the delicacy of the skill exploitation algorithm to simultaneously incorporate the new and old orders. This will help manufacturing firms to execute their manufacturing processes efficiently.
TL;DR: A cross-layer approach to improve MPEG-4 trans missions over WLANs, and a measurement admission control scheme for IEEE 802.11e Wlans is adopted.
Abstract: In this paper, we study MPEG-4 transmissions over the IEEE 802.11 wireless local area networks (WLANs). First, we provide a simulation of MPEG-4 using OPNET over the WLANs in terms of throughput, impacts of multiple MPEG-4 streams, and compression rate on throughput. Our simulation results show that a higher throughput does not always yield a better quality MPEG-4 video. We further observe that if an I frame of MPEG 4 video is lost, the next N-1 frames (all P and B frames) are useless [where N is the total number of frames contained within one group of picture (GoP)]. Furthermore, we observe that the I, P, and B frames are in decreasing order of importance. Therefore, we propose a cross-layer approach to improve MPEG-4 trans missions over WLANs. In the proposed approach: 1) P and B frames will be discarded by the MPEG-4 decoder at the receiver's medium access control (MAC) layer if the corresponding I fame is lost; 2) the individual MPEG-4 frames are prioritized at the MAC layer so that I frames have a higher priority than P frames, which have a higher priority than the B frames; 3) each frame (I, B, P) has a time deadline field so that if the deadline cannot be reached, the frame and other related P and B frames in the same GoP are deleted without further transmissions/re-transmissions; and 4) if the delay between an I frame and the next P frame is too long, then it may be better to drop the least important B frames in an attempt to allow the video to catch up. Finally, we study MPEG-4 transmissions over the IEEE 802.11e WLANs, and we adopt a measurement admission control scheme for IEEE 802.lie. Our results show the advantages of the proposed scheme.
TL;DR: This article reports on the design of a SOA platform, the "Service and Application Integration” (SAI) system, targeting novel approaches for legacy data and systems integration in the maritime surveillance domain, and develops a proof-of-concept of the main system capabilities.
Abstract: Maritime-surveillance operators still demand for an integrated maritime picture better supporting international coordination for their operations, as looked for in the European area. In this area, many data-integration efforts have been interpreted in the past as the problem of designing, building and maintaining huge centralized repositories. Current research activities are instead leveraging service-oriented principles to achieve more flexible and network-centric solutions to systems and data integration. In this direction, this article reports on the design of a SOA platform, the “Service and Application Integration” (SAI) system, targeting novel approaches for legacy data and systems integration in the maritime surveillance domain. We have developed a proof-of-concept of the main system capabilities to assess feasibility of our approach and to evaluate how the SAI middleware architecture can fit application requirements for dynamic data search, aggregation and delivery in the distributed maritime domain.
TL;DR: The concept of system of systems is introduced and attempts to apply it to China's emergency management, suggesting some possible problems and challenges in the design of EMSoS in China.
Abstract: This paper introduces the concept of system of systems and attempts to apply it to China's emergency management. Based on the characteristics of system of systems, we provide some principles and concerns for the design of an Emergency Management System of Systems (EMSoS) in China. Three figures representing the EMSoS structure are presented to illustrate the design and operation of emergency supply reserve centers, synergism of resources in the operation of the EMSoS, and the early warning system for emergent events. The research also proposes a concept of seamless rescue by coordinating government and non-government organizations, as well as other available civil resources. We conclude this paper by suggesting some possible problems and challenges in the design of EMSoS in China.
TL;DR: A new hybrid genetic algorithm with exhaustive searching for fine local searching is proposed to determine the production schedule in the factories, and is compared with a set of well known benchmarking problems, and demonstrates that it outperforms many other existing algorithms.
Abstract: Distributed planning problems are commonly found in today's production environment because of supply chain integration. Different factories vertically partner up and work collaboratively to increase their overall competitiveness. Although they are collaborating, factories are independent entities belonging to different companies in many practical situations. They individually face their own production capacity constraints, maximizing their own benefits, and planning production to satisfy their customer orders, especially in fulfilling those committed ones. This scenario is similar to some factories producing electrical home appliances in Mainland China. The objective of this paper is to study the collaboration strategy that they adopted, and propose a new strategy for better collaboration. For simulation, a new hybrid genetic algorithm with exhaustive searching for fine local searching is proposed to determine the production schedule in the factories. The proposed algorithm is compared with a set of well known benchmarking problems, and the results demonstrate that it outperforms many other existing algorithms. Moreover, a number of numerical examples have also been run to demonstrate the strength of the new collaboration strategy in minimizing the tardiness in new orders, meanwhile avoiding tardiness in committed orders.
TL;DR: It is found that if a tidal current flow regime at a particular location has been properly studied over time, its variations can be accurately predicted for both operational (Short Term) and planning (Long Term) purposes.
Abstract: Numerous techniques have been suggested for extracting energy from the sea. Tidal current turbines are a convenient method for extracting power from oceanic currents. Tidal turbines share many similarities to wind turbines; however due to the higher density of sea water they can produce 800-900 times more power when compared to an equivalent wind turbine of similar size operating at the same speed. Apart from having remarkable power densities, tidal currents are robust to aesthetic issues like the lack of wind or fog that can affect other renewables. The nature of tide formation makes them very predictable, and so in a general sense tidal energy is very reliable; which is a crucial factor in successful integration of renewable resources into the grid. In this study the authors have tested the predictability of tidal currents using various algorithms and ultimately based on the conventional harmonic analysis of tides and model free estimators a new prediction method has been proposed. The performance of the proposed method is then tested using actual recorded data. It is found that if a tidal current flow regime at a particular location has been properly studied over time, its variations can be accurately predicted for both operational (Short Term) and planning (Long Term) purposes.