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排序方式: 共有57条查询结果,搜索用时 15 毫秒
11.
In this paper, a generic retailer-oriented portfolio simulation system linking manufacturer, retailer, and customer in apparel supply chain is presented. The purpose of the simulator is to generate a portfolio consisting of replenishment strategy and performance index under different sales forecasting errors to satisfy the retailerdefined customer service level in apparel industry. After analyzing the main parameters in the portfolio simulator,the procedure and detailed structure of the simulator are then described. With the use of data from the industry, one case study of the portfolio simulator is achieved and the process of the simulation is validated.  相似文献   
12.
A web camera based multi-camera convergent close-range photogrammetric system is developed to obtain the neonates' head and facial morphology. The data will then be used to develop a secure and good-fitting eye-patch protector for neonates, particularly whoa they are exposed to bright lights such as phototherapy light. Measurements obtained by the system are evaluated and validated against data obtained from optical scanning. Results show that the photogrammetric system meets the requirements of measuring accuracy and safety for neonate in the neonatal units.  相似文献   
13.
含裂纹缺陷脆性岩石的峰值强度模型   总被引:4,自引:0,他引:4  
在分析Ashby和Hallam含缺陷脆性介质峰值强度理论模型基础上,对其进行修正,并用修正的理论模型研究单轴作用下,含裂纹缺陷花岗岩试样的裂纹萌生、扩展、贯通和相互作用等因素对峰值强度的影响规律。通过与物理试验和数值模拟结果对比分析发现:修正后的Ashby-Hallam强度模型能定量地预测含缺陷岩石的峰值强度,以及定性分析峰值强度同裂纹缺陷密度和裂纹贯通密度的关系;含裂纹缺陷脆性岩体的峰值强度主要与贯通的裂纹数以及缺陷的分布和缺陷大小有关。  相似文献   
14.
From Tetrahymena thermophila (strain BF5), the coding region of Cd-MT gene was cloned and sequenced. and identified as MTT1 isoform. A serial duplicate structure is discovered in its amino acid sequence, which separates the coding region into three parts (Part 1:7-61; Part 2:64-118; Part 3:122-162). The alignments among them and comparison with the corresponding parts of MT1 isoform suggest that MT1 and MTT1 isoforms both come from the same ancient gene that is homologous to Part 1, and Cd-MTs of Tetrahymena are aroused by such ancient gene duplication. The prediction of secondary structures and the analysis of the disulfide-bonding state of cysteine show that there are a lot of differences between MT1 and MTT1 isoforms, which maybe relate to their function mechanism.  相似文献   
15.
Wong GK  Liu B  Wang J  Zhang Y  Yang X  Zhang Z  Meng Q  Zhou J  Li D  Zhang J  Ni P  Li S  Ran L  Li H  Zhang J  Li R  Li S  Zheng H  Lin W  Li G  Wang X  Zhao W  Li J  Ye C  Dai M  Ruan J  Zhou Y  Li Y  He X  Zhang Y  Wang J  Huang X  Tong W  Chen J  Ye J  Chen C  Wei N  Li G  Dong L  Lan F  Sun Y  Zhang Z  Yang Z  Yu Y  Huang Y  He D  Xi Y  Wei D  Qi Q  Li W  Shi J  Wang M  Xie F  Wang J  Zhang X  Wang P  Zhao Y  Li N  Yang N  Dong W  Hu S  Zeng C  Zheng W  Hao B  Hillier LW  Yang SP  Warren WC  Wilson RK  Brandström M  Ellegren H  Crooijmans RP 《Nature》2004,432(7018):717-722
We describe a genetic variation map for the chicken genome containing 2.8 million single-nucleotide polymorphisms (SNPs). This map is based on a comparison of the sequences of three domestic chicken breeds (a broiler, a layer and a Chinese silkie) with that of their wild ancestor, red jungle fowl. Subsequent experiments indicate that at least 90% of the variant sites are true SNPs, and at least 70% are common SNPs that segregate in many domestic breeds. Mean nucleotide diversity is about five SNPs per kilobase for almost every possible comparison between red jungle fowl and domestic lines, between two different domestic lines, and within domestic lines--in contrast to the notion that domestic animals are highly inbred relative to their wild ancestors. In fact, most of the SNPs originated before domestication, and there is little evidence of selective sweeps for adaptive alleles on length scales greater than 100 kilobases.  相似文献   
16.
液体状态方程研究   总被引:1,自引:1,他引:0  
由自由体积理论研究了液体状态方程 .提出了一个普适的液体状态方程 ,由此状方程出发 ,可导出大多数液体状态方程 ,这对实际应用有一定指导意义  相似文献   
17.
HT-7U装置纵场线圈的稳态及瞬态传热分析   总被引:1,自引:1,他引:0  
文章分析了 TH- 7U托卡马克核聚变装置在正常和非正常运行情况下产生的各种热负荷在纵场磁体上的热行为 ,给出了纵场线圈盒最严重部位上的温度分布云图 ,计算过程考虑了核热沉积、各种热传导、热辐射、涡流损耗热和迫流式超临界氦进行对流换热等过程。针对等离子体快速破裂时 ,在极短的时间内 ,其纵场磁体中产生的较大涡流损耗而引起的焦耳热对纵场线圈盒与超导磁体之间的热传递过程加以研究。该文采用国际上较为流行的有限元分析软件 COSMOS/ M进行计算 ,由于简化了纵场线圈有限元分析模型及真实情况下部分热流量的不确定性 ,所得结果较为乐观 ,但这些结果对 HT- 7U装置的工程设计仍具有重要意义。  相似文献   
18.
本风险研究从地理和管理标准 ,定殖和定殖后扩散的可能性、经济影响评估和传入的可能性及风险管理措施等 6个方面对马铃薯腐烂线虫进行了风险评估 ,结果证实了马铃薯腐烂线虫在中国广泛定殖的可能性和定殖后扩散的可能性及经济影响和进入的可能性都很大 ,从而马铃薯腐烂线虫随从疫区的马铃薯、郁金香、风信子、唐昌蒲等繁殖材料而传入中国的风险极高 ,因此将马铃薯腐烂线虫列为禁止输入的危险性有害生物。  相似文献   
19.
元胞自动机交通流运动是利用交通流基本参数来研究加速规则、减速规则、换道规则和车辆移动的变化规律,最重要的是利用车辆速度v来确定不同时间不同交通流条件下的车辆速度变化特性.结合国、内外有关元胞自动机交通流研究的经验和方法,通过分析在同一地点、时间尺度为1 min的交通流在t与t+1时刻的平均速度变化关系来确定基于时间短时尺度的元胞自动机城市快速路路段交通流的速度变化概率,并总结出不同条件下的加、减、匀速概率P,为研究基于时间尺度的元胞自动机城市快速路路段交通流模型提供重要的数据分析基础.  相似文献   
20.
The sequence of the rice genome holds fundamental information for its biology, including physiology, genetics, development, and evolution, as well as information on many beneficial phenotypes of economic significance. Using a “whole genome shotgun” approach, we have produced a draft rice genome sequence ofOryza sativa ssp.indica, the major crop rice subspecies in China and many other regions of Asia. The draft genome sequence is constructed from over 4.3 million successful sequencing traces with an accumulative total length of 2214.9 Mb. The initial assembly of the non-redundant sequences reached 409.76 Mb in length, based on 3.30 million successful sequencing traces with a total length of 1797.4 Mb from anindica variant cultivar93-11, giving an estimated coverage of 95.29% of the rice genome with an average base accuracy of higher than 99%. The coverage of the draft sequence, the randomness of the sequence distribution, and the consistency of BIG-ASSEMBLER, a custom-designed software package used for the initial assembly, were verified rigorously by comparisons against finished BAC clone sequences from bothindica andjapanica strains, available from the public databases. Over all, 96.3% of full-length cDNAs, 96.4% of STS, STR, RFLP markers, 94.0% of ESTs and 94.9% unigene clusters were identified from the draft sequence. Our preliminary analysis on the data set shows that our rice draft sequence is consistent with the comman standard accepted by the genome sequencing community. The unconditional release of the draft to the public also undoubtedly provides a fundamental resource to the international scientific communities to facilitate genomic and genetic studies on rice biology. These authors contributed equally to this work.  相似文献   
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