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New Approach to the Power selection for Asynchronous Motor

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Journal of Donghua University(English Edition) 2001年第2期18卷 133-139页

作者：高建华胡洪国杨汝清 Res. Inst. of Robotics Shanghai Jiaotong Univ. Shanghai 200030 China

The heating calculation of three-phase squirrel- cage asynchronous motor on the condition of starting for a prescribed rotary angle is firstly studied with time dissection method and its corresponding algorithm is provided. Then based upon the algorithm, a new method for motor power selection is established. Motor initial power determined by load power ischecked and modified in terms of time crit erion, heating criterion,and starting torque *** appropriate motor power which meets three criterions is obtained at last, in the meantime, working displacement matrix andfrequency matrix used for control are acquired. Lifting motor of MDJ1800 low-level high- speed palletizer is taken as a reaI case in the paper.

关键词： time dissection, heating calculation, frequent starting,power selection, three-phase squirrel-cage asynchronous motor

Parameters selection in gene selection using Gaussian kernel support vector machines by genetic algorithm

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2005年第10期6卷 961-973页

作者：毛勇周晓波皮道映孙优贤 WONG Stephen T.C. National Laboratory of Industrial Control Technology Institute of Modern Control Engineering Zhejiang University Hangzhou 310027 China Harvard Center for Neurodegeneration and Repair Harvard Medical School and Brigham and Women’s Hospital Harvard Medical School Harvard University Boston MA 02115 USA

In microarray-based cancer classification, gene selection is an important issue owing to the large number of variables and small number of samples as well as its non-linearity. It is difficult to get satisfying results by using conventional linear sta- tistical methods. Recursive feature elimination based on support vector machine (SVM RFE) is an effective algorithm for gene selection and cancer classification, which are integrated into a consistent framework. In this paper, we propose a new method to select parameters of the aforementioned algorithm implemented with Gaussian kernel SVMs as better alternatives to the common practice of selecting the apparently best parameters by using a genetic algorithm to search for a couple of optimal parameter. Fast implementation issues for this method are also discussed for pragmatic reasons. The proposed method was tested on two repre- sentative hereditary breast cancer and acute leukaemia datasets. The experimental results indicate that the proposed method per- forms well in selecting genes and achieves high classification accuracies with these genes.

关键词： Gene selection, Support vector machine (SVM), Recursive feature elimination (RFE), Genetic algorithm (GA),Parameter selection

Media-specific rate allocation in heterogeneous wireless networks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第5期7卷 713-726页

作者： JURCA Dan FROSSARD Pascal Ecole Polytechnique Fédérale de Lausanne Signal Processing Institute Lausanne CH-1015 Switzerland

We address the problem of joint path selection and rate allocation in multipath wireless streaming, in order to optimize a media specific quality of service. We leverage on the existence of multiple parallel wireless services, in order to enhance the received video quality at a wireless client. An optimization problem is proposed, aimed at minimizing a video distortion metric based on sequence-dependent parameters, and transmission channel characteristics, for a given wireless network infrastructure. Even if joint optimal path selection and rate allocation is in general an NP complete problem, an in-depth analysis of the media distortion evolution allows defining a low complexity optimal streaming strategy, under reasonable network assumptions. In particular, we show that a greedy allocation of rates along paths with increasing error probability leads to an optimal solution. We argue that a network path should not be chosen for transmission, unless all other available paths with lower error probability have been chosen. Moreover, the chosen paths should be used at their maximum end-to-end bandwidth. These results are demonstrated for both independent network paths, and non-disjoint channel segments, in generic network topologies. Simulation results showed that the optimal rate allocation carefully trades off total encoding/transmission rate, with the end-to-end transmission error probability and the number of chosen paths. In many cases, the optimal rate allocation provides more than 20% improvement in received video quality, compared to heuristic-based algorithms.

关键词： Multipath streaming, Path selection, Rate allocation, Video streaming

A new type SVM——projected SVM

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Science China(Physics,Mechanics & Astronomy) 2004年第Z1期47卷 21-28页

作者： ZHU Yongsheng ZHANG Youyun Theory of Lubrication and Bearing Institute Xi'an Jiaotong University Xi'an 710049 China Theory of Lubrication and Bearing Institute Xi'an Jiaotong University Xi'an 710049 China

Support vector machine (SVM), developed by Vapnik et al., is a new and promising technique for classification and regression and has been proved to be competitive with the best available learning machines in many applications. However, the classification speed of SVM is substantially slower than that of other techniques with similar generalization ability. A new type SVM named projected SVM (PSVM), which is a combination of feature vector selection (FVS) method and linear SVM (LSVM), is proposed in present paper. In PSVM, the FVS method is first used to select a relevant subset (feature vectors, FVs) from the training data, and then both the training data and the test data are projected into the subspace constructed by FVs, and finally linear SVM(LSVM) is applied to classify the projected data. The time required by PSVM to calculate the class of new samples is proportional to the count of FVs. In most cases, the count of FVs is smaller than that of support vectors (SVs), and therefore PSVM is faster than SVM in running. Compared with other speeding-up techniques of SVM, PSVM is proved to possess not only speeding-up ability but also de-noising ability for high-noised data, and is found to be of potential use in mechanical fault pattern recognition.

关键词： support vector machine, feature vector selection, machine learning, projected SVM, speedup of SVM.

Animal Reproduction Technologies-FuturePerspectives

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Journal of Agricultural Science and Technology(A) 2016年第5期6卷 301-313页

作者： Jane Morrell Patrice Humblot Department of Clinical Sciences Swedish University of Agricultural Sciences (SLU) Box 7054 SE-75007 Uppsala Sweden

Reproductive biotechnologies, such as artificial insemination, sperm selection and embryo technologies, offer possibilitiesfor animal producers to increase reproductive efficiency. There have been many significant developments in reproductivebiotechnologies over the last few decades, e.g., in sperm handling and preservation, in vitro embryo production and preservation,sexing and cloning. This review discusses some of the key changes that have occurred and explores their potential for increasing thereproductive efficiency of domestic animals in the future. As a consequence, they also offer opportunities to facilitate or accelerategenetic selection. If properly used, they may contribute to increase the sustainability of animal production. The role of epigenetics ininfluencing phenotype is also considered.

关键词： Animal reproduction technologies, livestock, genetic selection, conservation breeding, sperm, embryo production,epigenetics, future perspectives.

A new theoretical model for the origin of amino acid homochirality

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Science China(Life Sciences) 2007年第5期50卷 580-586页

作者： HAN DaXiong1, CHEN WeiZhu2, HAN Bo2 & ZHAO YuFen1,2 1 Department of Pharmacy, Medical College of Xiamen University, Xiamen 361005, China 2 Department of Chemistry, Xiamen University, Xiamen 361005, China Department of Pharmacy Medical College of Xiamen University Xiamen 361005 China Department of Chemistry Xiamen University Xiamen 361005 China Department of Pharmacy Medical College of Xiamen University Xiamen 361005 China Department of Chemistry Xiamen University Xiamen 361005 China

Amino acid homochirality, as a unique behavior of life, could have originated synchronously with the genetic code. In this paper, phosphoryl amino-acid -5′-nucleosides with P-N bond are postulated to be a chiral origin model in prebiotic molecular evolution. The enthalpy change in the intramolecular interaction between the nucleotide base and the amino-acid side-chain determines the sta-bility of the particular complex, resulting in a preferred conformation associated with the chirality of amino acids. Based on the theoretical model, our experiments and calculations show that the chiral selection of the earliest amino acids for L-enantiomers seems to be a strict stereochemi-cal/physicochemical determinism. As other amino acids developed biosynthetically from the earliest amino acids, we infer that the chirality of the later amino acids was inherited from the precursor amino acids. This idea probably goes far back in history, but it is hoped that it will be a guide for further ex-periments in this area.

关键词： genetic code, phosphate, origin of life, chiral selection, homochirality

In vitro selected peptides bind with thymidylate synthase mRNA and inhibit its translation

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Science China(Life Sciences) 2007年第5期50卷 630-636页

作者： YAN Song1,2, NIU RongLi2, WANG Zheng2 & LIN XiuKun2 1 School of Environmental Science and Engineering, Dalian Jiaotong University, Dalian 116028, China 2 Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China School of Environmental Science and Engineering Dalian Jiaotong University Dalian 116028 China Key Laboratory of Experimental Marine Biology Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Key Laboratory of Experimental Marine Biology Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China

Thymidylate synthase (TS),an essential enzyme for catalyzing the biosynthesisof thymidylate,is a critical therapeutic target in cancer *** studies have shown that TSfunctions as an RNA-binding protein by interacting with two different sequences on its ownmRNA,thus,repressing translational *** this study,peptides binding TS RNA with highaffinity were isolated using mRNA display from a large peptide library (>10^(13) differentsequences).The randomized library was subjected up to twelve rounds of in vitro selection *** the amino acid composition of the selected peptides (12th round,R12) withthose from the initial random library (round zero,R0),the basic and aromatic residues in theselected peptides were enriched significantly,suggesting that these peptide regions might beimportant in the peptide-TS mRNA *** the amino acids at each random positionbased on their physicochemical properties and comparing the distributions with those of the initialrandom pool,an obvious basic charge characteristic was found at positions 1,12,17 and 18,suggestingthat basic side chains participate in RNA *** structure prediction showed that theselected peptides of R12 pool represented a helical propensity compared with R0 pool,and the regionswere rich in basic *** electrophoretic gel mobility shift and in vitro translation assaysshowed that the peptides selected using mRNA display could bind TS RNA specifically and inhibit thetranslation of TS *** results suggested that the identified peptides could be used as new TSinhibitors and developed to a novel class of anticancer agents.

关键词： thymidylate synthase, mRNA display, selection, affinity peptides

Small Modular Reactor Site Considerations for Uganda

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Journal of Energy and Power Engineering 2016年第12期10卷 717-725页

作者： Mukyala Kevin Robert Murray Field Department of Nuclear Power Plant Engineering KEPCO International Nuclear Graduate School (KINGS) Ulsan 45014 Korea

Uganda principally depends on hydropower for electricity generation. However, expansion of hydropower resources islimited, and with growing population and demand for electricity, the government of Uganda is considering integration of nuclearpower into its energy mix. With the current and projected grid capacity, SMR （small modular reactor） technology is attractive sincecapacity can be added incrementally. This paper therefore presents results for SMR site selection in Uganda. Starting with twentyregional areas established by the Ugandan government, a site selection process is outlined which uses four levels of screening andranking. First, exclusion criteria including seismicity, volcanic activity, water resources, and transportation distances were *** reduced the potential regional areas down to eight. Next, MAUT （multi-attribute utility theory） weighting was assigned to theseeight areas for：（1） distance to large population centers, （2） ease of transportation, and （3） distance to seismically or volcanically activeareas. From this ranking, four regional areas stood out and were then selected. These regions were then compared using variousattributes including access to water and integration with the developing national grid. In the final step, the lead candidate region wassubdivided into subzones to further refine the selection process.

关键词： SMR, site selection, site evaluation, reserve suitable area, MAUT, nuclear power plant.