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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
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WAN Ming-liang FENG Wei-song MIAO Wei WONG Ming-hong 《武汉大学学报:自然科学英文版》2005,10(5):925-930
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
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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
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基于时间短时尺度的城市快速路路段元胞自动机交通流速度变化概率分析 总被引:1,自引:1,他引:0
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
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YU Jun HU Songnian WANG Jun LI Songgang WONG Ka-Shu Gane LIU Bin DENG Yajun DAI Li YUAN Longping YANG Huanming 《科学通报(英文版)》2001,46(23):1937-1942
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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人工神经网络及其在金融预报中的应用 总被引:5,自引:0,他引:5
讨论了人工神经网络在金融汇率预报中的应用。其中介绍了广义交互验证(Generalized Cross Validation)法如何应用于确定神经网络中隐层的个数,并用实例说明了该方法甚至对复杂的非线性函数也可以得到很好的逼近。详细地介绍了运用人工神经网络作两周向前汇率预报的计算步骤。其平均相对误差(APE)为10*E-3的数量级,而国际上通用的状态空间模型及Box-Jenkins的ARIMA模型的预报误差都在10*E-2的数量级。 相似文献
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为了有效识别中文微博的观点句,提出了基于Hownet词典及模板的特征提取方法,并使用SVM算法对微博中的观点句进行识别。运用新设计的一个模板匹配的方法来进行特征提取,并通过计算其信息增益筛选出最后的特征模板。实验结果表明:算法具有优越性和有效性。 相似文献
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玻璃纤维片材在我国产量大,价格便宜,但受到应用研究的限制,在结构的加固改造行业中应用较少.介绍了14根钢筋混凝土梁的试验研究情况,其中10根试验梁为抗弯加固,其余为抗剪加固.分别就不同强度混凝土与玻璃纤维片材之间的粘结情况,玻璃纤维片材的粘贴方法,粘贴层数进行了研究.结果表明,粘贴玻璃纤维片材可显著提高强度,但强度的提高并不与粘贴层数成正比. 相似文献