This paper presents a wideband impedance matching technique of integrated antennas and CMOS low noise amplifiers for a multi-band UWB receiver. Reflection and insertion loss are reduced by the direct interconnection b...
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An ad hoc network is a cooperative engagement of a collection of mobile nodes without the required intervention of any centralized access point or existing infrastructure. Topology control is needed in ad hoc networks...
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An ad hoc network is a cooperative engagement of a collection of mobile nodes without the required intervention of any centralized access point or existing infrastructure. Topology control is needed in ad hoc networks to conserve energy and maximizing network lifetime while maintaining network connectivity. In this paper, a brief review of current topology control protocols for mobile ad hoc networks is presented and a new protocol has been proposed which is relying on leader election and density based clustering.
This paper addresses the problem of product fault anticipation and prevention during conceptual design of mechanical engineering products by introducing the concept of undesired functions as potential fault causes. Th...
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ISBN:
(纸本)0791841731
This paper addresses the problem of product fault anticipation and prevention during conceptual design of mechanical engineering products by introducing the concept of undesired functions as potential fault causes. The undesired functions considered in this paper are induced during solution principle synthesis and affect a product either by reducing the input of its intended functions or by producing undesired outputs, and can be processed either by determining and optimizing their distribution function, or by finding inverse, consecutive or comp.nsation functions to them. The formal definition of the generic process of processing undesired functions bases on its subdivision into elementary steps, each step being described by its states and the according state transition. Object patterns and process patterns are adopted for the representation of the static and dynamic design knowledge respectively. The concept is verified with a product example from mechanical engineering.
Transforming abstract algorithm specifications into executable code is an error-prone process in the absence of sophisticated comp.lers that can automatically translate such specifications into the target distributed ...
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ISBN:
(纸本)0769521320
Transforming abstract algorithm specifications into executable code is an error-prone process in the absence of sophisticated comp.lers that can automatically translate such specifications into the target distributed system. This paper presents a framework that was developed for translating algorithms specified as Input/Output Automata (IOA) to distributed programs. The framework consists of a methodology that guides the software development process and a core set of functions needed in target implementations that reduce unnecessary software development. As a proof of concept, this work also presents a distributed implementation of a reconfigurable atomic memory service for dynamic networks. The service emulates atomic read/write shared objects in the dynamic setting where processors can arbitrarily crash, or join and leave the comp.tation. The algorithm implementing the service is given in terms of IOA. The system is implemented in Java and runs on a network of workstations. Empirical data illustrates the behavior of the system.
An ad hoc network is a cooperative engagement of a collection of mobile nodes without the required intervention of any centralized access point or existing infrastructure. Developing efficient multi-path routing proto...
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An ad hoc network is a cooperative engagement of a collection of mobile nodes without the required intervention of any centralized access point or existing infrastructure. Developing efficient multi-path routing protocols in ad hoc environment is a challenging task due to changing network connectivity. Specifically, at low mobilities, the performance of most of the existing protocols is fairly good, but at high mobilities and stressful environments, their performance is not as good as expected. We have designed a new routing protocol called Node Disjoint Multi-path Ad hoc Routing (NDMA), which gives multiple node-disjoint paths between a source and a destination pair. Our protocol is capable of routing the traffic over multiple paths. We have analyzed the performance of our protocol by carrying out simulations and comp.red its performance with existing single path such AODV and multi-path version of DSR protocol. We observed that NDMA performs much better than AODV and DSR. The metrics in our performance analysis are normalized routing load and average end to end delay. We have also proposed a model for the expected lifetime after which a fresh route discovery has to be initiated in case of disjoint multi-path routing.
This paper investigates the use of several lightly supervised and data-driven approaches to Mandarin broadcast news transcription. First, with a consideration of the special structural properties of the Chinese langua...
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This paper investigates the use of several lightly supervised and data-driven approaches to Mandarin broadcast news transcription. First, with a consideration of the special structural properties of the Chinese language, a fast acoustic look-ahead technique for estimating the unexplored part of speech utterance was integrated into the lexical tree search to improve the search efficiency, in conjunction with the conventional language model look-ahead technique. Then, a verification-based method for automatic acoustic training data acquisition was developed to make use of the large amount of untranscribed speech data. Finally, two alternative strategies for language model adaptation were further studied for accurate language model estimation. With the above approaches, the system yielded an 11.94% character error rate on the Mandarin broadcast news collected in Taiwan.
This paper describes the xml definition of class algebra which is available at http://***/∼dan/***. A sample user-defined ontology document and inst.nce document are available at http://***. ***/∼dan/*** and http://...
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We present a distributed algorithm to comp.te bandwidth max-min fair rates in a multi-rate multicast network. The significance of the algorithm, comp.red to previous algorithms [1], [2], [3], is that it is more scalab...
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We propose a mixed-mode orthogonal frequency domain multiplexing (OFDM) symbol shaping scheme to reduce digital-to-analog (D/A) requantization error in multiband OFDM ultra-wideband (UWB) systems. This method enhances...
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This paper describes an analytical framework for the weighted max-min flow control of elastic flows in packet networks using PID and PII2 controller when flows experience heterogeneous round-trip delays. Our algorithm...
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