Fabry - Perot interference in a nanotube electron waveguide

The behaviour of traditional electronic devices can be understood in terms of the classical diffusive motion of electrons. As the size of a device becomes comparable to the electron coherence length, however, quantum interference between electron waves becomes increasingly important, leading to dramatic changes in device properties. This classical-to-quantum transition in device behaviour suggests the possibility for nanometer-sized electronic elements that make use of quantum coherence. Molecular electronic devices are promising candidates for realizing such device elements because the electronic motion in molecules is inherently quantum mechanical and it can be modified by well defined chemistry. Here we describe an example of a coherent molecular electronic device whose behaviour is explicitly dependent on quantum interference between propagating electron waves-a Fabry-Perot electron resonator based on individual single-walled carbon nanotubes with near-perfect ohmic contacts to electrodes. In these devices, the nanotubes act as coherent electron waveguides, with the resonant cavity formed between the two nanotube-electrode interfaces. We use a theoretical model based on the multichannel Landauer-Büttiker formalism to analyse the device characteristics and find that coupling between the two propagating modes of the nanotubes caused by electron scattering at the nanotube-electrode interfaces is important.     

隧道凿岩机器人的车体定位方法

讨论了国内自行研制的隧道凿岩机器人利用安装在隧道上的激光,使钻壁上的两个激光靶与激光过难,采集各关节传感器的值并做数据处理,能得到精确的车体到隧道断面的坐标变换矩阵,实现车体的精确定位,同时根据推导公式的特性,介绍了一种简单的定位方法。     

比喻义的训释与比喻义的形成--《现代汉语词典》比喻义计量研究之一

运用计量统计的方法,分析了<现代汉语词典>(1983年版)中2488条比喻义的释义特点及所反映的词义性质.概括出了六种释义类型,反映出两种不同性质的比喻义固定比喻义与语境比喻义.固定比喻义是指已经凝固为稳定词义成分的比喻义,已成为词典释义中的一部分.语境比喻义是指靠具体上下文来显示的比喻义,以例句的形式来体现.<现代汉语词典>对比喻义的处理方法在词汇学与词典学有着独到的贡献再现了词义形成、稳定的过程;扩大了规范语文词典反映语言事实的范围,加强了语文词典的"引导"功能;丰富了词典的编纂技巧,完善了语文词典的表现手段.     

基于多层前馈型神经元网络模型的摄像机定标算法

针对传统线性、非线性摄像机定标算法的鲁棒性,提出了基于多层前馈型神经元（MLFN）网络模型来替代传统精确的摄像机定标数学模型,MLFN网络模型作为层状网络可实现任意维复杂的输入／输出映射,对于无需计算摄像机构,外参数的应用场合,该模型提供了一种实用且有较好鲁棒性的摄像机定标算法,同时为了补偿摄影机非线性畸变,把图像按畸变程度分割成两个区域,分别建立各自基于MLFN网络的摄像机定标模型,实验表明,该方法有效补了畸变,并提高了模型精度,给出了基于MLFN网络模型摄像机定标算法实验,验证了该模型的有效性。     

工科大学物理实验教学模式的探讨

主要阐述在做好基础实验的基础上 ,同时开设综合实验 ,进而鼓励应用计算机软件进行设计性实验。提出撰写实验报告的能力是实验教学不可忽视的教学环节 ,以最终趋向于“实践型、设计型”为目标来探讨工科物理实验教学模式     

基于平均换乘的城市公交线网性能评价

评价公交线网性能的指标有多种,其中交通网络的可达性指标是交通系统能否优质、高效完成运输任务的一项综合性评价指标,而平均换乘次数则能很好地反映这一指标．通过依次计算“公交n次换乘矩阵”的方法求出网络平均换乘次数,并根据平均换乘次数对公交线网的结构性能进行评价．     

Ru2 and Ru encode mouse orthologs of the genes mutated in human Hermansky-Pudlak syndrome types 5 and 6

Hermansky-Pudlak syndrome (HPS) is a genetically heterogeneous disease involving abnormalities of melanosomes, platelet dense granules and lysosomes. Here we have used positional candidate and transgenic rescue approaches to identify the genes mutated in ruby-eye 2 and ruby-eye mice (ru2 and ru, respectively), two 'mimic' mouse models of HPS. We also show that these genes are orthologs of the genes mutated in individuals with HPS types 5 and 6, respectively, and that their protein products directly interact. Both genes are previously unknown and are found only in higher eukaryotes, and together represent a new class of genes that have evolved in higher organisms to govern the synthesis of highly specialized lysosome-related organelles.     

蓝牙网络中BLUEPAC IP的分析与应用

在传统 IP协议的基础上 ,介绍了适用于 BLUEPAC网络的 BLUEPAC IP协议 ,给出了 BLUEPACIP协议栈的基本结构 ,讨论了 BLUEPAC网络的建立过程 ,以及如何在 BLUEPAC网络中实现移动用户的IP地址分配、路由选择及移动切换等问题 ,并对 BLUEPAC网络中 ,切换过程对系统信息速率所带来的影响进行了分析。最后 ,展望了 BLUEPAC IP协议在个人无线接入网络内的应用前景。     

Biological aspects on the cultures of the entomophthoralean fungus<Emphasis Type="Italic">Pandora delphacis</Emphasis> grown on broomcorn millets

Among entomopathogenic fungi the Entomophthor- ales plays an important role in natural control of insect pests through induction of epizootics in insect popula-tions[1—3]. Since most species of the fungal group are 4 - characteristic with their special capability of actively dis-charging conidia to favor infection and dissemination in host populations, they are ideal targets for epizootiologi-cal study, being considered as important microbial control agents. Currently, 66 species …     

决策支持系统在交通网络规划中的应用

介绍了交通规划决策支持系统开发中所需解决的问题,就交通规划过程中的数据管理,模型库的实现和数据库,模型库的接口等来对交通规划决策支持系统的实现做了进一步的研究探讨,对开发交通规划决策支持系统有一定的借鉴意义。