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91.
Ganapati Panda Pyari Mohan Pradhan Babita Majhi 《Expert systems with applications》2011,38(10):12671-12683
Conventional derivative based learning rule poses stability problem when used in adaptive identification of infinite impulse response (IIR) systems. In addition the performance of these methods substantially deteriorates when reduced order adaptive models are used for such identification. In this paper the IIR system identification task is formulated as an optimization problem and a recently introduced cat swarm optimization (CSO) is used to develop a new population based learning rule for the model. Both actual and reduced order identification of few benchmarked IIR plants is carried out through simulation study. The results demonstrate superior identification performance of the new method compared to that achieved by genetic algorithm (GA) and particle swarm optimization (PSO) based identification. 相似文献
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Soumya Priyadarsini Panda Ajit Kumar Nayak 《International Journal of Speech Technology》2017,20(4):959-976
Designing text-to-speech systems capable of producing natural sounding speech segments in different Indian languages is a challenging and ongoing problem. Due to the large number of possible pronunciations in different Indian languages, a number of speech segments are needed to be stored in the speech database while a concatenative speech synthesis technique is used to achieve highly natural speech segments. However, the large speech database size makes it unusable for small hand held devices or human computer interactive systems with limited storage resources. In this paper, we proposed a fraction-based waveform concatenation technique to produce intelligible speech segments from a small footprint speech database. The results of all the experiments performed shows the effectiveness of the proposed technique in producing intelligible speech segments in different Indian languages even with very less storage and computation overhead compared to the existing syllable-based technique. 相似文献
95.
Sundar N.S. Jayasimha D.N. Panda D.K. Sadayappan P. 《Parallel and Distributed Systems, IEEE Transactions on》2001,12(12):1201-1218
Parallel algorithms for several common problems such as sorting and the FFT involve a personalized exchange of data among all the processors. Past approaches to doing complete exchange have taken one of two broad approaches: direct exchange or the indirect message-combining approaches. While combining approaches reduce the number of message startups, direct exchange minimizes the volume of data transmitted. This paper presents a family of hybrid algorithms for wormhole-routed 2D meshes that can effectively utilize the complementary strengths of these two approaches to complete exchange. The performance of hybrid algorithms using Cyclic Exchange and Scott's Direct Exchange are studied using analytical models, simulation, and implementation on a Cray T3D system. The results show that hybrids achieve lower completion times than either pure algorithm for a range of mesh sizes, data block sizes, and message startup costs. It is also demonstrated that barriers may be used to enhance performance by reducing message contention, whether or not the target system provides hardware support for barrier synchronization. The analytical models are shown useful in selecting the optimum hybrid for any given combination of system parameters (mesh size, message startup time, flit transfer time, and barrier cost) and the problem parameter (data block size) 相似文献
96.
Economic pressures and "value" judgments both compel and contaminate the current debate on the efficacy of psychotherapy. Too often, complex clinical trial outcome studies ignore the clinical or treatment process, as well as personality or contextual variables. Thus, they fail to build the foundations of a clinical science that makes possible the development of individually tailored treatment approaches and outcome predictions for specific patients with unique personalities, symptoms, and life circumstances. The real challenge, therefore, is for each psychotherapeutic approach to delineate its "process steps" and relate these steps to different outcomes. The "process" is the "final common pathway" for a number of patient, therapist, technique, and contextual variables. The capacity to predict the relationship between process and outcome at each stage in a therapeutic procedure is the relevant clinical test of "efficacy." 相似文献
97.
beta-Ionone is found to stimulate considerably carotinoids synthesis in Blakeslea trispora. The stabilization of carotene-synthesizing ability of B. trispora in the presence of beta-ionine under prolonged incubation time is observed. Stabilization of polyribosomes in the presence of beta-ionine is observed when studying polyribosome content in B. trispora. A hypothesis is expressed on the existence of biochemical "receptors" as a linkage between synthesized protein and destroying mRNA. 相似文献
98.
This paper explores the suitability of the emerging passive star-coupled optical interconnection using wavelength division multiplexing as the system interconnect to provide high bandwidth (Gbits/sec) communication demanded by heterogeneous systems. Several different communication strategies (combinations of communication topologies and protocols) are investigated under a representative master-slave computational model. The interplay between system speed, network speed, task granularity, and degree of parallelism is studied using both analytical modeling and simulations. It is shown that a hierarchical ALOHA-based communication strategy between the master and the slaves, implemented on top of the passive star-coupled network, leads to a considerable reduction in channel contention and provides 50–80% reduction in task completion time for applications with medium to high degrees of coarse grain parallelism. Comparable reduction in channel contention is also shown to be achieved by using tunable acoustooptic filters at master nodes. 相似文献
99.
A number of wild plants, used by rural and tribal populations and contributing significantly to their livelihood and food security have escaped recognition and scientific inquiry. Their distribution, conservation, mode of harvest by locals and optimal use require region-specific assessment in order to integrate them into developmental interventions. This study analyzed the collection, consumption, sale and income from edible forest fruits in 49 tribal villages spread over five districts of Orissa State in eastern India. Density, dominance and diversity of species yielding wild fruit were measured by studying ecological parameters in the sample plots. We estimated an average of 48 fruit plants per hectare of deciduous forests. Fifty-six wild edible fruit species belonging to 40 genera in 26 families were recorded in the study region, many of which have multiple uses. Indigenous fruits formed part of the family diet with average annual consumption of 73 kg per household. Sale of wild fruits contributed 15 % of income for tribal households. Despite their good knowledge of indigenous fruits, the tribal populations have not adopted fruit tree farming which would enhance their nutrition and income. 相似文献
100.