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91.
文章介绍了ITU-TG.729A算法与ITU-TG.729B算法配合使用的语音编解码方案,并讨论了其在TI公司最新一代定点数字信号处理器(DSPs)TMS320C6416上实现的关键技术。G.729A是G.729编码器的简化版本,G.729B是带VAD(活动话音检测)的静音压缩算法。两者结合可以有效地降低码率,同时保持很好的合成语音质量。 相似文献
92.
Young-Suk Kim Chan-Il Kim Jun-Young Park Kyung-Hoan Na 《Metallurgical and Materials Transactions A》2005,36(1):169-176
The atomic force microscopy (AFM)-based nanolithographic technique is currently used to directly machine material surfaces
and fabricate nanocomponents for microelectromechanical systems (MEMS) devices. In the current study, three-dimensional molecular
dynamic (MD) simulations with potentials based on the Morse function were performed to evaluate the effect of crystallographic
factors and process variables on the nanodeformation characteristics of the nanolithography processing of monocrystalline
copper. Moreover, the effects of process variables (tool shape, cutting speed, and ploughing depth) on the nanostructural
pattern are investigated. The simulation results revealed that the crystal orientation and ploughing direction had a significant
influence on varying the forces (cutting force, thrust force, and width-direction force); the nature of the nanodeformation
ahead of the tool; and the surface quality of the machined material. 相似文献
93.
Unrelated parallel machine scheduling with setup times and a total weighted tardiness objective 总被引:2,自引:0,他引:2
This paper presents several search heuristics and their performance in batch scheduling of parallel, unrelated machines. Identical or similar jobs are typically processed in batches in order to decrease setup times and/or processing times. The problem accounts for allotting batched work parts into unrelated parallel machines, where each batch consists of a fixed number of jobs. Some batches may contain different jobs but all jobs within each batch should have an identical processing time and a common due date. Processing time of each job of a batch is determined according to the machine group as well as the batch group to which the job belongs. Major or minor setup times are required between two subsequent batches depending on batch sequence but are independent of machines. The objective of our study is to minimize the total weighted tardiness for the unrelated parallel machine scheduling. Four search heuristics are proposed to address the problem, namely (1) the earliest weighted due date, (2) the shortest weighted processing time, (3) the two-level batch scheduling heuristic, and (4) the simulated annealing method. These proposed local search heuristics are tested through computational experiments with data from dicing operations of a compound semiconductor manufacturing facility. 相似文献
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首先论述了可测性设计的概念,分析了时序电路测试生成面临的困境。然后介绍了可测性设计的专门方法,并举例说明了它在实际中的应用。 相似文献
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99.
Man Gyun Na Sun Ho Shin Dong Won Jung Soong Pyung Kim Ji Hwan Jeong Byung Chul Lee 《Nuclear Engineering and Design》2004,232(3):267-300
In this work, a probabilistic neural network (PNN) that has been applied well to the classification problems is used in order to identify the break locations of loss of coolant accidents (LOCA) such as hot-leg, cold-leg and steam generator tubes. Also, a fuzzy neural network (FNN) is designed to estimate the break size. The inputs to PNN and FNN are time-integrated values obtained by integrating measurement signals during a short time interval after reactor scram. An automatic structure constructor for the fuzzy neural network automatically selects the input variables from the time-integrated values of many measured signals, and optimizes the number of rules and its related parameters. It is verified that the proposed algorithm identifies very well the break locations of LOCAs and also, estimate their break size accurately. 相似文献
100.
In order to reduce the computation of complex problems, a new surrogate-assisted estimation of distribution algorithm with
Gaussian process was proposed. Coevolution was used in dual populations which evolved in parallel. The search space was projected
into multiple subspaces and searched by sub-populations. Also, the whole space was exploited by the other population which
exchanges information with the sub-populations. In order to make the evolutionary course efficient, multivariate Gaussian
model and Gaussian mixture model were used in both populations separately to estimate the distribution of individuals and
reproduce new generations. For the surrogate model, Gaussian process was combined with the algorithm which predicted variance
of the predictions. The results on six benchmark functions show that the new algorithm performs better than other surrogate-model
based algorithms and the computation complexity is only 10% of the original estimation of distribution algorithm. 相似文献