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In this paper, we propose a translation-based approach for performance prediction of composite service built on WS-CDL. To translate a composite service into a state-transition model for quantitative analysis, we first give a set of translation rules to map WS-CDL elements into general-stochastic-petri-nets (GSPN). Based on the GSPN representation, we introduce the prediction algorithm to calculate...
Flight delays (such as early or late arrivals and late departures) are a frequent occurrence in actual day to day airport operations and it is often not possible to assign such flights to their original gates. Flight delay information may also vary with time. As a consequence, the airport authority needs to reassign flights to different gates in real-time. The traditional manual flight reassignment...
State class methods are a fundamental and most widely applied technique for timing analysis of Time Petri Nets (TPNs). However, the existing state class methods are not suitable for the computation of global time delay, which is an important issue for real-time systems. This paper presents a state class method for the analysis and verification of global time properties in TPNs that addresses the problem...
As network infrastructure and home agent under tactical wireless environment are all movable and destructible, its mobile communication can't be solved by existing Mobile IP. So this paper proposed a new hierarchical distributed mobile interconnect protocol (HDMIP) in order to solve this problem. Firstly, the paper analyzed the particularity of mobile communication under tactical wireless environment,...
This paper presents dose control electronics and a digital addressing method for the vertically aligned carbon nanofiber (VACNF) based massively parallel maskless e-beam lithography system. The Digital Electrostatically focused e-beam Array direct-write Lithography (DEAL) developed by our research group in Oak Ridge National Laboratory incorporates digitally addressable field emission arrays (DAFEAs)...
IEEE 802.15.4 defines the physical layer and medium access control sub-layer specifications for low-data-rate wireless connectivity devices with very limited battery consumption requirements typically operating in the personal operating space. Unlike traditional wireless networks, its unique characteristics, such as low-data-rate and guaranteed time slots (GTS), have brought unprecedented challenges...
Embedded control systems with hard real-time constraints require that deadlines are met at all times or the system may malfunction with potentially catastrophic consequences. Schedulability theory can assure deadlines for a given task set when periods and worst-case execution times (WCETs) of tasks are known. While periods are generally derived from the problem specification, a task's code needs to...
Mobile ad hoc networks are self organizing multi-hop wireless networks with no fixed infrastructure. All the users in these networks are mobile. The mobiles communicate either directly or via other nodes of the network by establishing routes. The mobility of nodes causes the existing links to be break frequently. So if we can predict future movement, the resources reservation can be made before be...
Good indoor air quality (IAQ) can contribute to the safety, health and comfort of the people. Since indoor exposure to air contaminants penetrating from the indoor air contaminant sources depends on a number of parameters such as the ventilation rate, the geometric characteristics of the indoor environment, the indoor removal mechanisms and the concentration of air contaminants released, the implementation...
The algorithm of wavelet analysis can be used to estimate the time delay (TD) and Doppler stretch (DS) of Chirp signals, but it cannot suppress the effect of Gaussian noises. In this paper, a definition of fourth-order Wavelet-Cumulants is given by combining the wavelet and the forth-order cumulant. This method can be used in unknown Gaussian noise environment. The simulation results demonstrate the...
Capacity of Mobile Ad Hoc Networks using a single channel and a single interface reduces due to channel interference and collision. Use of multiple non overlapping channels increases the network capacity by allowing more concurrent transmissions. A single interface together with multiple channels results in high switching delay. As a result multiple interfaces should be used to reduce the switching...
For many control systems, control performance is strongly dependent on delay variations of the control tasks. Such variations can come from a number of sources including task preemptions, variations in task workloads and perturbations in the physical environment. Existing work has considered improving control task delay variations due to task preemption only. This paper presents a general adaptive...
Service mapping is an important part of Open and Reconfigurable Networks (ORN), which is proposed to solve the network convergence problem of emerging applications from the aspect of “application mapping to service, and service mapping to component”. This work introduces the ORN simply firstly; and then presents a general service model, which has four elements, such as Role, Protocol, Quality, and...
Optimization problem of flight sequencing on the ground of airport with multi-taxiway and multi-runway is resolved based on gene expression algorithm, and a standard algorithm of aircraft approach sequencing for airports with any topology structure in theory is approved. Based on an actual airport ground operation situation, a standard algorithm for the two runways of this airport is provided. Compared...
To optimize the multimedia proxy server effectively, this paper proposes a gain-based cache replacement policy using the multimedia proxy server gain model. The performance of the proposed gain-based policy is evaluated by simulation experiments. We compare it with some typical cache replacement policies in terms of the improvement on video quality, start-up delay, network resource cost.
In order to realize Remote Monitoring of wheelchair's user and Home environment, ZigBee-based network intelligent wheelchair system has been designed by using Wireless Sensor Networks, intelligent wheelchair, and communication modules. The system works on the existing TD-SCDMA network. This paper introduces the working principle, hardware and software designing. The design of sensor nodes, network...
In order to facilitate the adjustment of process parameters for tufting machine, a coordinated control system of tufting carpet machines using AC servo motor to feed yarn and backing cloth has been developed. The system adopt adjusting speed of the servo motors which directly connected with the according axis to fulfill the adjustment of yarn delivery and backing cloth feeding instead of adjustment...
Two way partitioning of a circuit represented as a graph, has been carried out using simulated annealing in the present work. The problem is solved in such a way that delay between the partitions is minimum. The parameters used in the annealing process are initial temperature, cooling rate, and threshold. The influence of these parameters on the delay between the partitions is evaluated. The method...
Last few decades has brought many fundamental changes to data communications and the Internet. Internet has its roots in a networking project started by ARPA which consisted of four computers. Now the Internet spans the However transition to the new version has been remarkably slow. Thus in the interim, various transition mechanisms can be employed. In this paper two such mechanisms, namely configured...
The output of VCLC sublayer was taken as the input of the VCA sublayer on CCSDS AOS, whose multiplexing efficiency and formed-time directly affect the performance of the virtual channel and whole system. Based on Poisson distribution, the research on multiplexing efficiency was transformed into the occurred probability of packets arriving. While establishing the probability and statistics model of...
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