Anticipated network performance improvements from migrating to protocols supporting greater bandwidths or from switching are unlikely in complex internetworks. In fact, you may even degrade performance for application...
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Anticipated network performance improvements from migrating to protocols supporting greater bandwidths or from switching are unlikely in complex internetworks. In fact, you may even degrade performance for applications distributed over networks. optimization of networks (inclusive of WANs, LANs, internetworks, and enterprise components) must begin as a fundament review of the network infrastructure. Although statistical modeling is essential for forecasting loads and response times under different network applications, protocols, designs, and technologies, the relationships between bandwidth and latency must be understood. Microsegmentation (the techniques of subnetting, LAN segmentation, and switching) for bandwidth enhancement is only effective to solve network overloads and bottlenecks, not performance delays;in fact, segmentation adds delay. While faster protocols and microsegmentation increase network bandwidth, these techniques are most applicable when network performance is compromised by extreme overloading and collision saturation. The disadvantage of microsegmentation is that it also increases the latency of internetwork transmissions due service times at intermediate nodes. Network performance optimization is a function, then, of fundamental design, rather than as post-operative facade that no amount of reengineering with faster protocols or switches can redress.
An architecture and methodology for executing a train control application in an ultra-safe manner is presented in this paper. Prior work in advanced train control systems are summarized along with their assumptions an...
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An architecture and methodology for executing a train control application in an ultra-safe manner is presented in this paper. Prior work in advanced train control systems are summarized along with their assumptions and drawbacks. A flexible architecture that allows fault-tolerant and fail-safe operation is presented for a distributed control system. A safety assurance technique which detects errors in software and hardware for simplex systems is presented in this paper. Performance results important to real-time control are obtained from modeling and simulating the architecture. An experimental prototype implementing the architecture and safety assurance technique is described together with experimental results.
INSYDE is a simulator developed to evaluate the performance of complex, large-scale systems. The simulator has already been used to evaluate several existing systems, the results of which are reflected in the designs ...
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INSYDE is a simulator developed to evaluate the performance of complex, large-scale systems. The simulator has already been used to evaluate several existing systems, the results of which are reflected in the designs of those systems. In this paper, we will introduce the model description method of INSYDE and review an example of application to a large-scale distributed processing system. The nodes of the input processing flow total about 12,000. Since it is impractical to input all operations unchanged when modeling, we have carried out various approximations to reduce the input scale.
The U.S. Army Corps of Engineers' North Pacific Division and Hydrologic Engineering Center applied a prescriptive reservoir model to the Columbia River system to suggestsystem operating rules. This paper presents...
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The U.S. Army Corps of Engineers' North Pacific Division and Hydrologic Engineering Center applied a prescriptive reservoir model to the Columbia River system to suggestsystem operating rules. This paper presents the methodology applied to formulate preliminary monthly operating rules using an economically derived objective function. The paper also shows a variety of display techniques and statistical methods used to scrutinize prescribed results. The paper compares prescriptive results with existing operations (represented by results from NPD's descriptive model). The two analysis methods produce very similar system wide operations, but significant differences exist for storage allocation among larger reservoirs such as Grand Coulee and Arrow. These similarities and differences are discussed regarding their potential significance.
The proceedings contain 170 papers. The topics discussed include: sound in context: soundscape research and composition at Simon Fraser University;a survey of gender issues related to computer music and strategies for...
The proceedings contain 170 papers. The topics discussed include: sound in context: soundscape research and composition at Simon Fraser University;a survey of gender issues related to computer music and strategies for change;the algorithmic muse: new listening paradigms and the harmonies of chaos;the international digital electroacoustic music archive;the Institute of Electroacoustics and Experimental Music at the Vienna University of Music;the electro-acoustic music studio at the Royal Academy of Music, Copenhagen;SynthBuilder demonstration - a graphical real-time synthesis, processing and performance system;score views - an object-oriented approach to a graphical computer music synthesis environment;an improvisational accompaniment system observing performer's musical gesture;and a hierarchical system for controlling synthesis by physical modeling.
An electromechanical simulator for cardiac catheter positioning testing has been developed to experimentally evaluate the Intraventricular Impedance Imaging (III) system performance. Such an approach eliminates numero...
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An electromechanical simulator for cardiac catheter positioning testing has been developed to experimentally evaluate the Intraventricular Impedance Imaging (III) system performance. Such an approach eliminates numerous problems associated with in vivo testing. This paper presents the results of such a modeling technique. The intraventricular probe positioning was realized as 3-D probe movement (static) or/and cardiac volume variation (dynamic), using hardware and/or software control modes. A ventricle imaging model was built using a 3-compartment simulator representing the blood, myocardium and lungs. Experimental results show that the model provides a static positioning resolution of 0.01-0.15 mm, dynamic volumetric resolution of 0.08 ml, and phantom resistivity contrast for blood:myocardium:lungs of 1:3.4:7.3.
In this research, a self-organizing fuzzy-nets optimization (FNO) system is developed to generate a knowledge bank that can show the required cutting power to be on-line for a short length of time in an NC verifier. T...
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In this research, a self-organizing fuzzy-nets optimization (FNO) system is developed to generate a knowledge bank that can show the required cutting power to be on-line for a short length of time in an NC verifier. The FNO system requires a self-learning procedure consisting of five steps. A generic system consisting of a fuzzification module and a defuzzification module is implemented to perform the procedure.
This paper explains the preparations undertaken to offer a new course on modeling of engineering systems. It details the factors motivating the development of such a course, its objectives, and the work plan being fol...
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This paper explains the preparations undertaken to offer a new course on modeling of engineering systems. It details the factors motivating the development of such a course, its objectives, and the work plan being followed for its preparation. Although this course will be offered to the electrical engineering students, it should be of significant interest to other engineering majors as well. The course involves the use of SIMULINK simulation software.
A new concept is proposed for an elevator group control system which can change control settings according to individual floor utilization situations. The floor attribute based control method uses a combination of flo...
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A new concept is proposed for an elevator group control system which can change control settings according to individual floor utilization situations. The floor attribute based control method uses a combination of floor attribute based evaluation and car attribute based evaluation. Computer simulations show it can improve multiple preferential floor settings at the same time. Additionally, an on-line parameter tuning method using genetic algorithms is proposed. The floor attribute control method needs some dozens of control parameters to be tuned according to each building's traffic, and the proposed method can do it. The elitest preserving strategy is an effective way to keep control stability. A diversity recovering operation, which initializes population, excluding the elitest individual, when traffic flow data have changed, improves the following ability for transitions of utilized conditions.
A regular operation of a water resource system, if adhered to long enough, often tends to become optimal. Typically, the overall economy and society surrounding a water resource system is relatively insensitive to its...
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A regular operation of a water resource system, if adhered to long enough, often tends to become optimal. Typically, the overall economy and society surrounding a water resource system is relatively insensitive to its operation. Recreation and water supply demands are affected relatively little by small changes in water availability compared to equally large changes in regional population, employment, income, and other factors. Water-related infrastructure to support these demands adapts to whatever water resources infrastructure and operating rules exist. The accumulation of such infrastructure and land use over time in response to relatively constant reservoir operating policies can result in those policies being relied upon to support these valued economic activities. Thus, any given set of water system operations becomes increasingly expensive to change and so can become more optimal over time. Some illustrative examples are presented.
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