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This paper addresses the problem of scheduling periodic tasks on a uniprocessor using static priority assignment without preemption. The problem of non-preemptive fixed priority scheduling has received little attention until recently, while real-life applications are often based on non-preemptive systems especially in case of embedded systems. In this paper, we show that Rate Monotonic priority assignment is optimal for non-preemptive scheduling when each task's relative deadline is equal to its period. We have derived a schedulability bound for non-preemptive Rate Monotonic scheduling by using period ratio of the tasks to provide a guarantee that tasks will meet their deadlines. Since the obtained bound is relatively small comparing with the preemptive scheduling, we also propose a method for designing high-utilization non-preemptive system to enhance the utilization bound. [ABSTRACT FROM AUTHOR]

The lack of source IP address checking makes it easy for the attackers to spoof the source address. Spoofing Prevention Method (SPM), as a prospective candidate to be deployed in the Internet, is a newly proposed scheme to solve this problem. However, there is no work on SPM prototype system. In this paper, we present our experience in achieving a prototype system for SPM. In addition to realizing the basic idea of SPM described in the original paper, we make the following three contributions: First, the detail design is made for the whole SPM system architecture and detail mechanisms. Second, several important issues for SPM system are addressed, e.g., how to carry the key required by SPM, the MTU problem, etc. Third, a prototype system is made and some experiments are done with this prototype system. [ABSTRACT FROM AUTHOR]

Many service discovery protocols have been proposed by far to support ubiquitous computing. But they don't always apply to ubiquitous computing because of their confines. In this paper, we propose a service discovery protocol named VPDP adopted in our DOM-based middleware architecture, which aims to support as many types of ubiquitous environments as possible. VPDP is important for our middleware architecture to accommodate heterogeneity and uncertainty of ubiquitous computing environments. [ABSTRACT FROM AUTHOR]

Wireless Mesh Networks (WMNs) with a promising future in wireless backhauling applications have attracted the attention of many network research centers and academic researches. High throughput and low delay as essential requirements of a wireless back-bone network demand new topology control algorithms as well as new optimization metrics. In this paper, a topology control algorithm compliant with the structure of WMNs is proposed, as well as a new metric combining the characteristics of different network layers. The proposed metric is compared with the conventional ones such as distance and interference where even an increase of over 100% in the capacity of the network is presented by applying this metric. [ABSTRACT FROM AUTHOR]

This paper deals with the realization of retrieval and feature description systems for clusters by using logical rule generations based on the Genetic Programming (GP). At first, whole data is divided into several clusters and the rules are improved based the GP. The fitness of individuals is defined in proportion to the hits of corresponding logical expression to the samples in targeted cluster c, but also in inversely proportion to the hits outside the cluster c. The GP method is applied to various real world data by showing effective performance compared to conventional methods. [ABSTRACT FROM AUTHOR]

The abstract should summarize the contents of the paper and should contain at least 70 and at most 150 words. It should be set in 9-point font size and should be inset 1.0 cm from the right and left margins. There should be two blank (10-point) lines before and after the abstract. This document is in the required format. Roadmapping, as a strategic planning tool, is attracting increasing applications in industries. By applying the principles of Interactive Planning (IP), this paper puts forward a new solution for making personal academic research roadmaps. Then this paper introduces an ongoing project that is to develop a roadmapping support system based on the solution, and gives some considerations about applying the i-System Methodology for enhancing the knowledge creation in a roadmapping process. [ABSTRACT FROM AUTHOR]

Recently atomic cluster structures have been intensively studied because of their importance in physics, chemistry and material science. However, finding the lowest energy structure, which is the most stable configuration, is NP-hard. Differential Evolution (DE) algorithm is a new heuristic approach which mainly has three advantages: finding the true global minimum regardless of the initial parameter values, fast convergence, and using few control parameters. In this paper we describe a new search method that uses differential evolution (DE) algorithm to optimize the geometry of small argon atom clusters. Experimental results show that the exact global optimal configuration of argon clusters with atom number N≤ 16 can be found in a reasonable computing time, and approximate optimization can also be obtained for clusters with N=30. From their 3-D geometry structures, we can see that their optimal energy structures are highly symmetrical. [ABSTRACT FROM AUTHOR]

The technology of electronic design automation (EDA) has improved the efficiency of design process, however, designer is still required much special knowledge of circuit. During the past decade, using genetic algorithm (GA) to design circuit had attracted many experts and scholars. However, too much more attention was focus on a circuit's function and many other factors had been neglected which caused the circuit had little applicability. This paper proposes an automated design approach for analog circuit based on a multi-objective adaptive GA. The multi-objective fitness evaluation method, which can dynamic adjust parameter, is selected. And a parallel evolution strategy which separates evolution of circuit structure and element value is adopted but also organically combined them by weight vectors. The experimental results indicate that this approach obviously be able to improve the evolution efficiency and could generate numbers of suitable circuits. [ABSTRACT FROM AUTHOR]

The genetic algorithm (GA) often suffers from the premature convergence because of the loss of population diversity at an early stage of searching. This paper proposes a steep thermodynamical evolutionary algorithm (STEA), which utilizes a steep thermodynamical selection (STS) rule. STEA simulates the competitive mechanism between energy and entropy in annealing to systematically resolve the conflicts between selective pressure and population diversity in GA. This paper also proves that the rule STS has the approximate steepest descent ability of the free energy. Experimental results show that STEA is both far more efficient and much stabler than the thermodynamical genetic algorithm (TDGA). [ABSTRACT FROM AUTHOR]

In this paper, a protocol, called recursive priority inheritance (RPI) protocol, is proposed to solve complicated priority inversion problems as well as basic one. Our proposed protocol is implemented and tested in the Linux kernel. Additionally, the performance of our proposed protocol is evaluated and compared with previous protocols in the aspect of time and space complexity analyses. [ABSTRACT FROM AUTHOR]

In real-time systems, demand paging has not been used since worst case performance analysis technique for demand paging is not available. In this paper, we propose a technique to obtain the worst case bound on the demand paging costs and devise a worst case response time analysis framework considering the demand paging costs. We divide the technique into two different methods, DP-Pessimistic and DP-Accurate, depending on the accuracy and the complexity of analysis. DP-Accurate considers the page reuses among task instances and thus gives more accurate analysis results. We evaluate the accuracy of the proposed techniques comparing the analysis results from DP-Accurate and DP-Pessimistic. [ABSTRACT FROM AUTHOR]

The system response time is one of the most critical user's requirements. Therefore, a response time analysis must be done at the design stage. This paper proposes a response time analysis method based on ‘Fuzzy-Timing Petri net with choice probabilities (FTCP)'. FTCP is a modified version of timed net: A delay time associated with a transition is not a crisp number but a possibility distribution function and a transition of FTCP is also associated with a choice probability. We are proposing a response time analysis procedure for FTCP. It is similar to the minimum cycle time analysis for Timed Nets. The difference is that we take account of choice probabilities of the transitions in the process of generating the T-invariant. The other feature of our analysis method is that it can handle temporal uncertainties. This paper finally demonstrates the usefulness of the method by applying the method on a Web Service System. [ABSTRACT FROM AUTHOR]

In today's Internet routing architecture, the router doesn't validate the correctness of the source address carried in the packet, nor keep the state information when forwarding the packet. Thus the DDoS attacks with spoofed IP source address can cause security problems. In this paper, we aim to prevent the attackers from attacking somewhere outside the IPv6 edge network with forged source address in the fine granularity. The proposed methods include source address authentication by using session key and hash digest algorithm, and replay attack prevention by combining the sequence number method and the timestamp method. This paper presents the algorithm design and evaluates its feasibility and correctness by simulation experiments. [ABSTRACT FROM AUTHOR]

Web service composition is a promising technology to effectively integrate distributed autonomous services in service oriented paradigm. When providing composite services, ensuring user experienced QoS (Quality of Service) in dynamic environment poses a great challenge. In this paper, we present a distributed service selection approach for optimizing composite service with complex structures. The approach does not require a centralized QoS registry to have complete composition logic, but runs on our distributed QoS architecture iteratively. Experimental results show that the approach is efficient and effective for our problem. [ABSTRACT FROM AUTHOR]

In this paper, a design for a low-power 512-bit synchronous EEPROM with flash cells for passive UHF RFID tag chip is presented. Applied are low-power schemes such as dual power supply voltage(VDD=1.5V and VDDP=2.5V), clocked inverter sensing, voltage-up converter, IO interface, and Dickson charge pump using schottky diode. An EEPROM is fabricated with the 0.25μm- EEPROM process. Simulation results show that power dissipations are 8.34μW in the read cycle and 57.7μW in the write cycle, respectively. The layout size is 449.3μm × 480.67μm. [ABSTRACT FROM AUTHOR]

This paper is a study related to phonemic analysis of Korean speech. For speech recognition, the best method is that speech should be recognized as phonemic unit. However, to segment speech into phonemic units is not well-applied because of various changes of phonation. Therefore, I in this study try to arrange a phonemic system of Korean speech and segment speech into phonemic units on the base of the phonemic system of Hunminjeongeum, the Korean script. I also look for the features of each phoneme by observing the changes of frequency domain, mel bandwidth and mel capstrum of phoneme and aim to form the phonemic segmentation system of Korean speech. [ABSTRACT FROM AUTHOR]

Passage retrieval is a base of answer extracting in Chinese question answering system.In order to improve the precision of the passage retrieval which includes answers, this paper analyze first existing passage retrieval methods,and point to their shortcomings, then put forward a new method of passage retrieval, in which factors are considered ,such as frequency of query words and query expansion words in passage, the length of passage, the distribution density and minimum match span of query words and query expansion words in passage ,when calculating passage weight.The new method can realize passage retrieval on the basis of the weight calculation, and obtain optimization answers passage. Final, experiment result of answer extracting based on passage retrieval have shown that the method given has better effect. [ABSTRACT FROM AUTHOR]

When wireless senor networks (WSNs) are deployed in hostile areas, they indeed need to be secured by security mechanisms. To do this, cryptographic keys must be agreed on by communicating nodes. Unluckily, due to resource constraints, the key agreement problem in wireless sensor networks becomes quite intricate. In this paper, we propose a new ID-based random key pre-distribution scheme that is comparable to Du et al.'s scheme [2] in terms of network resiliency and memory usage. On the other hand, our later analysis shows that our scheme outperforms Du et al.'s scheme in terms of computational and communication overhead. [ABSTRACT FROM AUTHOR]

In this paper, we propose an adaptive mobile system that uses mobile grid computing to achieve infeasible work in mobile device. Recently, grid computing has gained significance for its ability to achieve certain goals by sharing the idle resources of computing devices, and thus overcoming the various constraints of the mobile computing environment. In the mobile environment, it is very important for mobile devices to recognize correctly their resource state. The proposed system includes a Grid Inference Engine, which decides on the resource state by using fuzzy logic. In this paper, a prototype is implemented to evaluate the proposed system. The effectiveness of the system is confirmed through experiment. [ABSTRACT FROM AUTHOR]

The paper presents the performance comparison between the triangle routing and the route optimization. The paper presents not only the analytical models to compare the performance but also the threshold value to decide whether the mobile node had better use the route optimization or not. The model provides the approximate guideline when a network administrator is to implement mobile IPv6 with the route optimization under the given network environments. [ABSTRACT FROM AUTHOR]

In this paper, we apply multiple antennas to MB-OFDM UWB system for high performance. With an emphasis on a preamble design for multi-channel separation, we address the channel estimation in MB-OFDM system with multiple antennas. By properly designing each preamble for multiple antennas to be orthogonal in time domain, the channel estimation can be applied to the MB-OFDM proposal for IEEE 802.15.3a standard in the case of more than 2 transmit antennas. By using the multi-antenna scheme and proposed channel estimation technique, the reliability and performance of MB-OFDM system can be improved. [ABSTRACT FROM AUTHOR]

Hierarchical Mobile IPv6 (HMIPv6) was proposed by the Internet Engineering Task Force (IETF) for efficient mobility management of Mobile IPv6 nodes. In HMIPv6, when a mobile node moves access router in the different MAP domain, such a movement is called macro mobility handover. In this situation, the mobile node creates new RCoA and LCoA and performs registrations with the new MAP and HA. Especially, until the address registrations with an MAP and HA are completed, the mobile node cannot receive IP packet and it is hard to actualize seamless services. Therefore, we need to execute the macro mobility handover in advance to reduce the handover latency and packet loss. We propose a scheme that is able to improve the macro mobility handover efficiently in HMIPv6. To do this we will adjust the user's mobility patterns to edge access routers between different MAP domains in the handover situation. In this paper, we compare cost of the macro mobility handover of the proposed scheme with that of the original HMIPv6. As a result, we can obtain the improved macro mobility handover in HMIPv6. [ABSTRACT FROM AUTHOR]

Mobile devices pay the telecommunication cost of downloading Internet data proportional to the amount of data transferred. This paper introduces a special ad hoc network in which several mobile devices, called peers, to cooperate each other to reduce the overall cost to download Internet content. Each peer downloads a specific portion of the content over 3G connection and exchanges the portion with other peers over the ad hoc connection in order that all participating peers are able to reconstruct the whole content. This paper proposes a peer-based content distribution method, and compares its performance with a similar one named per-packet based distribution method. The simulation results indicate that per-peer based method outperforms the per-packet based method. In addition, approximately 90% of the telecommunication cost is saved with as few as 10 peers. [ABSTRACT FROM AUTHOR]

Reducing the location update cost has been a critical research issue since the location update process requires heavy signaling traffics. One of the solutions is employing the hierarchical structure in cellular networks to reduce the location update cost. This paper is not only to measure the average location update cost in cellular networks using the hierarchical structure but also to determine the degree of the hierarchy which minimizes the location update cost. The paper proposes an advanced analytical model to obtain the optimal hierarchy in cellular networks, considering the update rates of the two registers, HLR and VLR, as well as the update delays for them. Also, the paper provides the threshold values as a guideline for the network administrator to design the optimal hierarchical structure in cellular networks. [ABSTRACT FROM AUTHOR]

IEEE 802.16e Task Group has developed an IEEE 802.16 amendment supporting mobile terminals such as PDAs, phones, and laptops. The energy efficiency design is an important research issue for mobile terminals due to limited battery power of them. In this paper, we study the energy efficiency design of IEEE 802.16e. For the purpose of power efficient operation, there are two sleep mode operations related to normal data traffic in the current IEEE 802.16e specification. We propose analytical models of the two sleep mode operations and conduct their performance comparison in terms of the power consumption and the frame response time. [ABSTRACT FROM AUTHOR]

This paper proposes an optimized topology control scheme (GA-OTC) based on a genetic algorithm for clustering-based hierarchical wireless sensor networks (WSNs). By using a genetic algorithm, we can obtain optimal solutions to multiple objective functions according to the two criteria of both balanced energy consumption and minimized total energy consumption of cluster heads while the entire WSNs field is covered by clusters. Through performance evaluation studies, we show that GA-OTC achieves desirable properties. [ABSTRACT FROM AUTHOR]

In the 1990s, innovation has become the main resource of competitive advantage for firms. Computer-mediated team innovative activities provide much more information, thus resulting in information overload. In this paper, the method for identifying the affirmative and negative relationship between the solution and its comment is proposed. The identification model is set up and applied in team innovation. In the model, we improve the traditional feature extraction method from three aspects: classifying feature words into six levels according to their affirmative and negative tone, introducing the new feature of the prior comment's attitude and the new feature of the number of sub-sentences. The results show that the method realizes the identification of the affirmative and negative relationship effectively. It can benefit organizing the large amount of team comments effectively and increase the efficiency of information organization. [ABSTRACT FROM AUTHOR]

Facing complex and changing emergencies decision makers need to obtain sufficient background knowledge to make effective decisions. We outline the characteristics of requirements for decision-making around knowledge sources, agility and the nature of knowledge products in quick responses to emergencies. We characterize the process of knowledge management in emergencies as quotation, manufacture and supply of a special product - Emergency Knowledge Product. From the point of view of achieving agility, we draw on the operational mechanism of the Agile Supply Chain (ASC) to construct Agile Knowledge Supply Chain (AKSC), a first in this paper. According to Similarities between ASC and AKSC, here we depict definition and architecture of AKSC. AKSC can explore a new approach to knowledge-based quick responses in the emergency decision-making support. [ABSTRACT FROM AUTHOR]

This paper proposes a fast handoff scheme between PDSNs (Packet Data Serving Nodes) which provide packet services to a mobile node. The proposed handoff scheme does not require reestablishment of a PPP connection that may occur in the process of performing handoff between PDSNs. The handoff method between PDSNs requires that the PDSNs should receive subscribers' information about mobile nodes from their neighbor PDSNs forming a communication network. When the PDSN recognizes the mobile node moving into its coverage area, it can quickly establish a communication channel with the mobile node based on the subscriber information received already. As a result, the handoff is performed without reestablishing PPP. Therefore, the handoff between PDSNs can be performed faster removing time needed for establishing a PPP session with a terminal and for terminating a previously set up PPP session. [ABSTRACT FROM AUTHOR]

Wireless Mesh Networks with static Transit Access Points (TAPs) have many advantages to connect different kinds of networks. While Mobile Ad hoc Networks still have many challenges to improve because of dynamic topology and security vulnerabilities, WMNs are the best solution for wireless communication recently. To utilize the characteristics of WMN's topology, in this paper, we propose an algorithm to preserve privacy for routing. This idea comes from the fact that if we can separate data traffic into more than one path, the probability to capture all traffic from intermediate node is very small. It means it is very difficult to launch traffic analysis attacks because of traffic confidentiality. In addition, to hide securely the real source and destination addresses a new technique is proposed along with an Adaptive Key Agreement Scheme. We apply Information Entropy to model our routing traffic and highlight the robustness of the algorithm. We also present a detail traffic evaluation observed from neighboring nodes to show the availability of our proposal in term of robustness, loop free and computational overhead. [ABSTRACT FROM AUTHOR]

In this paper, the particle swarm optimization (PSO) algorithm with constriction factor approach (CFA) is proposed to optimal hydro generators governor Proportional-Integral-Derivative (PID) gains for small hydraulic transients. And four different integral performance criteria of turbine speed deviation such as integrated absolute error (IAE), integral of time weighted absolute value of error (ITAE), integral of squared error (ISE) and integral of time weighted squared error (ITSE) have been taken as fitness function respectively, and the differences have been investigated and compared. A step speed disturbance test on no-load operation has been performed. The digital simulation results show that the proposed PSO method has stable convergence characteristic and good computational ability, and it can effectively optimal hydro generators governor PID gains. And the dynamic performance of hydro generators governor system for small hydraulic transients is much better if ITAE criterion is applied as fitness function. [ABSTRACT FROM AUTHOR]

It is recognized that evolutionary algorithms are inspired from evolutionary biology. In this paper, we set up a thermodynamic model of evolutionary algorithm. This model is intuitive and has a solid foundation in thermodynamics. It is our first step towards a unified theory of evolutionary algorithms. [ABSTRACT FROM AUTHOR]

A heuristic particle swarm optimization (HPSO) is proposed as a solution to one-dimensional cutting stock problem (1D-CSP), which incorporate genetic operators into particle swarm optimization (PSO). In this paper, a heuristic strategy that is based on the results of analysis of the optimal cutting pattern of particles with successful search processes is described, which process a global optimization problem of the cutting-stock as a sequential optimization problem by multiple stages. During every sequential stage, the best cutting pattern for the current situation is researched and processed. This strategy is repeated until all the required stocks have been generated. The simulation results prove the effectiveness of the proposed methodology. [ABSTRACT FROM AUTHOR]

In large-scale, complicated Wireless Sensor Networks, the cooperation among sensor nodes is a key topic, and has been receiving more and more attention. The dynamic coalition mechanism in Multi-Agent System is an important method for this topic, and then an energy-efficient coalition formation algorithm is needed since the energy resource of WSN is restricted. This paper proposes a WSN coalition formation algorithm based on Ant Colony System with dual-negative feedback characteristic. Coalition sponsor inclines to wake those sensor nodes which seldom or never joined coalitions before to form coalition, which can balance the energy consumption among sensor nodes, so as to extend the network lifetime for more tasks. The results of simulation experiment show the validity of this algorithm. [ABSTRACT FROM AUTHOR]

In this paper, we make an investigation into the discontinuous parameter identification in the case of elliptic problem. The discontinuous parameter is identified by evolutionary algorithm for the first time. For this kind of problem, we present a two-level evolutionary algorithm. The first level is the evolution for discontinuous point and the second level is the evolution for parameter. The numerical experiments suggest that the algorithm carries such features as good stability and adaptability and is not very sensitive to the noise in observation data as well. [ABSTRACT FROM AUTHOR]

This paper describes metaheuristic algorithm based on simulated annealing method,which is a nature-inspired method, to analyze and improve the efficiency of the design of Global Positioning System (GPS) surveying networks. Within the context of satellite surveying, a positioning network can be defined as a set of points which are coordinated by placing receivers on these point to determine sessions between them. The problem is to search for the best order in which these sessions can be observed to give the best possible schedule. The same problem arise in Mobile Phone surveying networks. Several case studies have been used to experimentally asses the performance of the proposed approach in terms of solution quality and computational effort. [ABSTRACT FROM AUTHOR]

In high bit rate optical fiber communication systems, Polarization mode dispersion (PMD) is one of the main factors to signal distortion and needs to be compensated. PMD monitoring system is the key integral part of an adaptive PMD compensator. The degree of polarization (DOP) ellipsoid obtained by using a polarization scrambler can be used as a feedback signal for automatic PMD compensation. Generally, more than several thousands of sampling data of states of polarization (SOP) must be collected to insure getting a correct DOP ellipsoid. This would result in an unacceptable time consuming for adaptive PMD compensation. In this paper, we introduce the particle swarm optimization (PSO) algorithm in determining the real-time DOP ellipsoid with high precision, requiring only 100 sampling data of SOPs. Experimental results confirm that the PSO algorithm is effective for ellipsoid data fitting with high precision within 250ms using our hardware environment. [ABSTRACT FROM AUTHOR]

The integrated network (mixed with fixed network, cellular wireless network and ad hoc network etc.) would have different dynamic properties to the single-technique-based network, such as the movement of nodes and the change of delay of links. In this paper, we propose a new dynamic multicast routing model with a mechanism called local rearrangement to handle the changes in integrated network. Furthermore, D-IOA, an immune algorithm based on clone process, which employs gene library to improve the effectiveness of D-IOA to meet the real-time requirement in online multicast routing fields, is given to optimize the multicast sub-tree within the range of local rearrangement. The simulation results indicate that our algorithm balances three metrics better compared with other two famous dynamic multicast routing algorithms. [ABSTRACT FROM AUTHOR]

In this paper, we propose to integrate particle swarm optimization algorithm into cultural algorithms frame to develop a more efficient cultural particle swarm algorithms (CPSA) for constrained multi-objective optimization problem. In our CPSA, the population space of cultural algorithms consists of n+1 subswarms which are used to search for the n single-objective optimums and an additional multiobjective optimum. The belief space accepts 20% elite particles form each subswarm and further takes crossover to create Pareto optimums. Niche Pareto tournament selection is further executed to ensure Pareto set to distribute uniformly along Pareto frontier. Additional memory of Pareto optimums spool is allocated and updated in each iteration to keep resultant Pareto solutions. Besides, a direct comparison method is employed to handle constraints without needing penalty functions. Two examples are presented to demonstrate the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Evolutionary Computation made great success from the theory of natural selection devised by Charles Darwin. It was a process of randomly searching but not emphasizing each individuals respective functions. This paper proposed a hybrid optimization algorithm framework trying to incorporate natural selection and survival of the fittest and birds of a feather flock together. Aiming at balancing search results and search speed, we adopted the search strategy to classify the individuals by their fitness. Individuals classification differentiated respective function in search process, thats the excellent individuals mine the local optimal solution and others explore the search domain to find new local optimal solution. Experimental findings support the theoretical basis of the proposed framework. [ABSTRACT FROM AUTHOR]

This paper proposes a real-observation quantum-inspired evolutionary algorithm (RQEA) to solve a class of globally numerical optimization problems with continuous variables. By introducing a real observation and an evolutionary strategy, suitable for real optimization problems, based on the concept of Q-bit phase, RQEA uses a Q-gate to drive the individuals toward better solutions and eventually toward a single state corresponding to a real number varying between 0 and 1. Experimental results show that RQEA is able to find optimal or close-to-optimal solutions, and is more powerful than conventional real-coded genetic algorithm in terms of fitness, convergence and robustness. [ABSTRACT FROM AUTHOR]

Linear programming (LP) is an important field of optimization. Even though, interior point methods are polynomial algorithms, many LP practical problems are solved more efficiently by the primal and dual revised simplex methods (RSM); however, RSM has a poor performance in hard LP problems (HLPP) as in the Klee-Minty Cubes problem. Among LP methods, the hybrid method known as Simplex-Genetic (SG) is very robust to solve HLPP. The objective of SG is to obtain the optimal solution of a HLPP, taking advantages from each one of the combined methods -a genetic algorithm (GA) and the classical primal RSM-. In this paper a new SG method named Improved Simplex Genetic Method (ISG) is presented. ISG combines a GA (with special genetic operators) with both primal and dual RSM. Numerical experimentation using some instances of the Klee-Minty cubes problem shows that ISG has a better performance than both RSM and SG. [ABSTRACT FROM AUTHOR]

In this paper, we developed an integrated multi-objective real-time controlled scheduling methodology for Dual Resource Constrained systems. The proposed methodology integrates simulation, neural network and fuzzy inference system approaches to obtain a schedule considering both state of the system and objectives. By means of a case study, we have demonstrated that the proposed methodology can be an effective tool for dynamic scheduling of DRC systems. [ABSTRACT FROM AUTHOR]

Based on maximal slack first, this paper proposes a novel energy-efficient scheduling algorithm for periodic real time tasks. The scheduling solution combines static priority and dynamic speed adjustment mechanism to save energy. Simulation results show that the proposed algorithm outperforms other major scheduling schemes. [ABSTRACT FROM AUTHOR]

In this paper, a fast real time link adaptation scheme for wireless communication systems is proposed. The proposed scheme is employing multi-stage adaptation controls based on channel state information (CSI). The optimal link adaptation scheme is known to have high complexity to implement, and it shoud be run iteratively to deal with time varying wireless channels in a short time. The proposed method determines the speed of channel variation using CSI's, then it applies the most appropriate link adaptation methodology or algorithm to the current time varying rate of channels. For examples, a simple up/down transmit power adjustment is used for the very fast time varying channel condition. On the other hand, the optimal link adaptation scheme is directly applied in the very slow varying channel state. The proposed multi-stage link adaptation scheme can be easily implemented in real time wirelss communication systems because of its capability of selecting an appropriate real time link adaptation scheme adaptively to each channel variation rate. The design example on the selected platform shows that the proposed scheme is very efficient in real time applications of the link adaptation in wireless communications, while its performance is maintained close to the optimal. [ABSTRACT FROM AUTHOR]

This paper proposes and analyzes bandwidth reclaim scheme for IEEE 802.11 WLAN, which may suffer from severe bandwidth waste resulting from not only the variation of transmission rate and message length but also the overallocation to the real-time traffic in compensating for the delay due to the intervention of non-real-time messages. Built on top of the weighted round robin scheduling policy, we address that the polling order rearrangement according to the degree of overallocation can enhance reclaimability of unused network time and that the rearranegable slot has its message pending at the rearranging time. The simulation results show that the proposed scheme is able to reclaim up to 52.3 % of bandwidth waste when the number of streams is 2 and that it also provides stable throughput for utilization of 0.5 through 0.8. [ABSTRACT FROM AUTHOR]

In wireless sensor networks, each sensor node has severe resource constraints in terms of energy, computing device, and memory space. Especially, the memory space of the platform hardware is much smaller than that of the other computing systems. In this paper, we propose a OTL, which is an on-demand thread stack allocation scheme for MMU-less real-time sensor operating systems. The OTL enables to adaptively adjust the stack size by allocating stack frame based on the amount of each function's stack usage. The amount of the function's stack usage is checked at compile-time, and the adaptive adjustment of the stack occurs at run-time. Our experimental results show that the OTL significantly minimizes the spatial overhead of the threads' stacks with tolerable time overhead compared with fixed stack allocation mechanism of the existing sensor operating systems. [ABSTRACT FROM AUTHOR]

Gnutella has many weaknesses. Queries are handled identically no matter how popular the querying objects are. Blind flooding causes a great amount of redundant messages. In this paper, we explore how to retain the simplicity of Gnutella, while addressing its inherent weaknesses. We propose GPP, a content location solution in which multiple proxy peers are adopted to help a source peer locate desired objects. The underlying philosophy is to route queries to the areas where more results can be found. Towards this end, peers in GPP collaborate to achieve better search performance. Simulation results show that GPP outperforms Modified BFS and s-APS. [ABSTRACT FROM AUTHOR]

Recently issued standard IEEE 802.15.4 is a novel standard to achieve some critical features of wireless sensor networks. In this paper, we propose the algorithm to allocate GTSs according to the packet arrival rate from end devices and the number of devices in beacon enabled mode of IEEE 802.15.4 star topology networks. From simulation results, we show that our proposed algorithm enhances throughput comparing with the original IEEE 802.15.4 that uses only CAP duration for transmission. [ABSTRACT FROM AUTHOR]

One crucial challenge in network flow monitoring is how to accurately and efficiently monitor the large volume of network flows. Several approaches proposed to address this challenge either lack flexibility adapting to greatly varying network traffic (e.g. sNetFlow), or require intensive computing resources (e.g. ANF). In this paper, we propose a novel double-sampling and hold approach for net work flow monitoring to tackle this challenge. We take a coarse-grained packet sampling to initially reduce the total number of monitored packets; then, an enhanced fine-grained sample and hold algorithm (ESHA) is adopted to selectively add packets into flow cache. By optimally adjusting the ESHA sampling rate and taking Early Removal flow cache management scheme, the flow information can be maximized with given limited system resources. Extensive simulation and experiment studies show that our approach can significantly improve both the accuracy and efficiency in network flow monitoring than other methods. [ABSTRACT FROM AUTHOR]