基于Java的基因本体工具包

针对基因本体的需求,利用Java技术,以模块化设计的方式实现了基因本体工具包GO4J.该系统包括4个模块.解析器模块把GO载入到内存中;图数据结构模块记录了所有的GO条目之间的关系;语义相似性模块评估两个GO条目之间的相似程度;可视化模块直观展示GO条目和根节点之间的路径.GO4J把这4个模块整合到本体浏览器中,可以结合GO注释的生物数据来对具体的生物数据进行分析.     

根据基因表达谱与基因功能模块研究大鼠抑郁症发病的分子机制

用Willner法构造大鼠抑郁症模型,由基因芯片检测8例模型和8例正常大鼠的基因表达谱,识别差异表达基因,寻找差异表达基因功能模块并构建基因表达相关网络,研究大鼠抑郁症模型的分子病理机制.在基因本体(GO)功能体系中寻找显著富集差异表达基因的疾病相关功能模块,提取疾病相关功能模块中的基因构造表达相关网络.从中选择显著多地与其它基因共表达的基因定义为HUB基因,并进一步研究其与疾病的关系.筛选得到207个差异表达基因及13个差异表达基因功能模块,主要涉及神经肽激素活性、信号传导通路、核糖体生成以及蛋白质转运与降解.在共表达相关网络中进一步识别了4个差异表达的HUB基因.利用基因功能模块和表达相关网络研究疾病机制的结果显示,抑郁症的发病可能涉及单胺递质的释放、信号传导以及神经肽激素调节等通路协同作用.     

基于FCM与粗糙集的连续数据知识挖掘方法

对连续数据知识挖掘可采用模糊C均值聚类将其离散化，再应用粗糙集进行约简．文中针对该过程中样本数据离散化后出现多个聚类中心隶属度值较接近的情况．提出了隶属度重叠度的方法来扩展对应离散类别的选取．离散类剐确定后再应用粗糙集理论对其进行知识挖掘，可得到连续数据的本质特性．此方法应用于汽轮机轴系振动数据的知识挖掘．与采用最大隶属度确定对应类别的方法相比，该方法不影响对连续数据的知识挖掘，并能真实反映连续数据的特性．     

基于粗糙集的企业技术创新能力更新方法研究

随着时间、环境的不断变化及企业技术创新能力的进一步要求,现有的技术创新能力已逐渐不能满足企业技术创新的要求,因此技术创新能力更新成为企业在新的要求下的一种能力行为。文章基于粗集理论研究了新要求下的企业技术创新能力更新方法,确定技术创新能力更新次序以达到更新费用最低,随后分析算法并通过实例证明其有效性。     

一种基于蝙蝠算法的多目标跟踪数据关联方法

针对多目标跟踪中的数据关联问题,提出了基于蝙蝠算法的数据关联方法。首先将多目标数据关联问题建模成组合优化问题,结合数据关联的特点,对蝙蝠算法的搜索更新规则进行改进,使其可以应用于多目标的数据关联问题,并给出了基于蝙蝠算法的多目标数据关联的详细流程。通过仿真实验和被动声呐实测数据测试表明,基于蝙蝠算法的多目标数据关联方法切实可行并且具有较好的效果。     

A new hole insertion method for level set based structural topology optimization

Structural shape and topology optimization using level set functions is becoming increasingly popular. However, traditional methods do not naturally allow for new hole creation and solutions can be dependent on the initial design. Various methods have been proposed that enable new hole insertion; however, the link between hole insertion and boundary optimization can be unclear. The new method presented in this paper utilizes a secondary level set function that represents a pseudo third dimension in two‐dimensional problems to facilitate new hole insertion. The update of the secondary function is connected to the primary level set function forming a meaningful link between boundary optimization and hole creation. The performance of the method is investigated to identify suitable parameters that produce good solutions for a range of problems. Copyright © 2012 John Wiley & Sons, Ltd.     

A structural optimization method based on the level set method using a new geometry‐based re‐initialization scheme

Structural optimization methods based on the level set method are a new type of structural optimization method where the outlines of target structures can be implicitly represented using the level set function, and updated by solving the so‐called Hamilton–Jacobi equation based on a Eulerian coordinate system. These new methods can allow topological alterations, such as the number of holes, during the optimization process whereas the boundaries of the target structure are clearly defined. However, the re‐initialization scheme used when updating the level set function is a critical problem when seeking to obtain appropriately updated outlines of target structures. In this paper, we propose a new structural optimization method based on the level set method using a new geometry‐based re‐initialization scheme where both the numerical analysis used when solving the equilibrium equations and the updating process of the level set function are performed using the Finite Element Method. The stiffness maximization, eigenfrequency maximization, and eigenfrequency matching problems are considered as optimization problems. Several design examples are presented to confirm the usefulness of the proposed method. Copyright © 2010 John Wiley & Sons, Ltd.     

基于大数据和粗糙集的产品需求分析方法研究

随着产品互联网时代的到来,针对传统产品设计需求的获取方法单一、实时性差、主观性过强等问题,提出了一种基于大数据分析和粗糙集理论的产品需求分析方法.采用网路爬虫技术,实时获取存在于多种信息载体中的大体量用户需求;利用大数据分析工具和粗糙集获取不同语义层次的用户需求类型的权重,并通过质量功能配置(quality function deployment,QFD)质量屋将用户需求转换为相应的工程设计参数,从而为准确获取反映用户需求的产品设计方向提供依据.以三星手机Galaxy S6Edge为例,通过对该款手机在微博和京东商城的产品用户评论等数据进行大数据分析,并结合粗糙集理论的用户需求计算方法,验证了提出方法的有效性.     

A novel level set method for image segmentation by combining local and global information

A novel level set method integrating local and global statistical information is proposed in this paper. In our method, a new signed pressure force (SPF) function is constructed by two parts. One is the global average intensity of the image, which can accelerate the evolution of the curve when the contour far away from the object boundaries. The other is the intensity average of difference image between the averaging convolution image and the original image, which can guide the evolving curve to catch the boundaries of the objects. In addition, an adaptive weighting function is utilized to adjust the ratio between the global and local terms, which can eliminate the inconvenient selection of weighting parameter. By substituting the new SPF function for the edge stopping function of the geodesic active contour model, we obtain a novel adaptive hybrid segmentation model, which is capable of segmenting the images with intensity inhomogeneity. What is more, in our method, the level set function is initialized with a binary function, which reduces the computational cost for the re-initialization step. The experimental results and comparisons with several popular models on synthetic and real images indicate that our method achieves superior performance in segmenting images with noise, low contrast and intensity inhomogeneity.     

基于多级关联信号树的高效可重构网包分类方法研究

针对高速网络中包分类严重影响路由系统性能提升的问题,进行了深入的实验性研究.针对传统包分类算法通过扩展规则搜索空间实现匹配,占用内存空间大,功耗高,吞吐率低的问题,研究了基于多级关联信号树的高效可重构网包分类方法.通过分析网包分类规则集合特点,提出了一种基于多级关联信号树的逻辑匹配结构,从中抽取出三类可重构的粗粒度网包分类基本计算单元——固定型匹配器、前缀型匹配器和范围型匹配器,用这三类匹配器构成了一个可重构网包分类阵列,通过配置匹配器的重构功能单元(RFU)层和匹配器之间的互联结构——重构互联网络(RIN)层实现了高速分类计算.该方法能够有效节省内存空间,降低功耗,大幅提升匹配速度.为了验证算法性能,在Xilinx公司的Virtex-6(model:XC6 VSX475T)芯片上进行仿真实验,实验结果表明该算法吞吐率可以达到100Gbp以上.     

An adaptive level set method based on two‐level uniform meshes and its application to dislocation dynamics

In this paper, we present an adaptive level set method for motion of high codimensional objects (e.g., curves in three dimensions). This method uses only two (or a few fixed) levels of meshes. A uniform coarse mesh is defined over the whole computational domain. Any coarse mesh cell that contains the moving object is further divided into a uniform fine mesh. The coarse‐to‐fine ratios in the mesh refinement can be adjusted to achieve optimal efficiency. Refinement and coarsening (removing the fine mesh within a coarse grid cell) are performed dynamically during the evolution. In this adaptive method, the computation is localized mostly near the moving objects; thus, the computational cost is significantly reduced compared with the uniform mesh over the whole domain with the same resolution. In this method, the level set equations can be solved on these uniform meshes of different levels directly using standard high‐order numerical methods. This method is examined by numerical examples of moving curves and applications to dislocation dynamics simulations. This two‐level adaptive method also provides a basis for using locally varying time stepping to further reduce the computational cost. Copyright © 2013 John Wiley & Sons, Ltd.     

基于粗糙集和神经网络的联合模式识别系统

提出了一种划分属性离散区间的新方法．针对这种划分，提出一种约简和去噪的方法．随后，建立了粗糙集和LVQ神经网络的联合模式识别系统．最后，比较了用该系统和仅用神经网络进行识别的效果，证明了该方法的有效性．     

基于分段常数水平集方法的声振耦合系统拓扑优化

针对结构与无限大声场的声振耦合系统中结构的双材料拓扑优化问题进行了研究。采用有限元与边界元方法分别对结构和声场进行离散。基于分段常数水平集(piecewise constant level set,PCLS)方法,构造了结构的刚度阵、质量阵与阻尼阵。优化目标选为最小化结构指定位置的振幅平方,采用伴随变量法进行灵敏度分析。引入二次罚函数方法来实现体积约束,基于灵敏度信息对优化参数进行重新定义,克服了参数的问题依赖性。数值结果表明优化设计可以显著降低结构的振幅,证实了优化方法的有效性。不同算例下体积约束在相同优化参数下均得到很好满足,说明了重新定义参数的优越性。     

Topology optimization of multi-material for the heat conduction problem based on the level set method

This article presents a numerical approach of topology optimization with multiple materials for the heat conduction problem. The multiphase level set model is used to implicitly describe the geometric boundaries of material regions with different conductivities. The model of multi-material representation has no emergence of the intermediate density. The optimization objective is to construct the optimal heat conductive paths which improve the efficiency of heat transfer. The dissipation of thermal transport potential capacity is taken as the objective function. The sensitivity analysis is implemented by the adjoint variable method, which is the foundation of constructing the velocity field of the level set equation. The optimal result is gradually realized by the evolution of multi-material boundaries, and the topological changes are naturally handled during the optimization process. Finally, the numerical examples are presented to demonstrate the feasibility and validity of the proposed method for topology optimization of the heat conduction problem.     

一种基于蜡质自组装的疏水涂层制备方法

用氯仿从荷叶表面提取蜡质,氯仿挥发后蜡质能够在载玻片上自组装形成疏水涂层。扫描电镜观察表明,荷叶蜡质自组装形成的微观结构与新鲜荷叶表面纳米级的管状结构非常类似;静态接触角测试表明,载玻片上的蜡质涂层接触角高达138°±5°;GC-MS分析表明,荷叶蜡质成分主要为长链脂肪烃、脂肪醇、脂肪酸、脂和少量酮。这种疏水表面原则上能按照荷叶蜡质成分及其含量比例关系溶解混合工业原料得到。     

3D散乱数据点分段二次逼近的曲面拟合

为进一步提高曲面重构的保形性及高效性,提出了一种自动构建光顺三角曲面的方法．该法首先通过构建三角形元覆盖边界域来构建一张曲面近似粗网,然后从点集中不断添加新点直至达到指定的容差,在每个插入数据点处构造C1连续的分片二次逼近面片,最终整体的C¹曲面由各三角形上的曲面片拼合而成．最后给出了该方法在真实点集上的运用结果并与其他方法所构造的逼近曲面形状进行了比较,结果表明,该方法对密集3D散乱数据点建模有效,生成的曲面质量高,误差小．该方法也适用于数据精简．     

ZnO薄膜的本征缺陷、p型掺杂及其新型功能器件

ZnO是一种宽禁带半导体材料(3.37eV),具有较高的激子结合能(60meV),室温下激子仍然存在。由于其结构特点及优异的光电性能,ZnO在微电子学、光电子学、集成光学和微电子机械系统等高技术领域有着广阔的应用前景,在国内外引起极大的关注。但本征的ZnO呈n型电导,p型ZnO的获得因较强的自补偿效应,存在较大困难,限制了其应用水平。针对ZnO目前的研究、就其本征缺陷、p型掺杂以及新型功能器件等方面做一简要评述。     

基于统计与粗糙集理论的飞机垂尾抖振载荷分布假设选择与评价方法

研究飞机垂尾抖振问题的主要任务之一是编制抖振疲劳载荷谱、估算飞机结构的抖振疲劳寿命并校核飞机结构的强度等,一般通过统计方法来建立其抖振疲劳载荷时程的峰(谷)值分布模型,而分布模型的优劣对确定各飞行状态下的极限工况及抖振响应的循环次数与幅值分布等信息影响显著。通过分析五种常用于描述抖振疲劳载荷峰(谷)值的概率分布假设模型：正态分布、对数正态分布、威布尔分布、瑞利分布和极值分布,给出了基于参数估计的概率分布规律,并提出了一种采用各概率分布假设所对应模型的“拟合优劣指标”作为评价和选择的依据。同时,结合各分布模型的特性对飞机抖振载荷时程处理要求的匹配程度,运用粗糙集理论确定了系统评价指标的最小分辨距离与最大分辨率,来消除由于误差引入导致的评价指标数值差异而造成的误判。算例分析表明,该方法可合理且高效地实现对飞机抖振载荷概率分布假设的正确评价与选择     

基于功能相关性的智能变电站二次系统功能测试验证方法

针对现有智能变电站二次系统功能测试结果仅通过观测二次设备行为得到,而未考虑设备行为背后的信息流程导致的被测功能正确性的误评估问题,该文利用分支流树建立能够反映功能与信息流关联关系的二次系统功能相关性模型,并以功能测试过程中的相关报文为触发条件,通过功能相关性模型与被测功能产生的信息对比进行被测功能正确性判断。通过自动布局算法完成测试过程中相关设备、链路、信息以及测试结果的展示。最后,通过在某220 kV智能变电站进行试验,证明该方法在测试环节中对功能正确性验证的有效性。     

A finite element‐based level set method for fluid–elastic solid interaction with surface tension

A numerical method for simulating fluid–elastic solid interaction with surface tension is presented. A level set method is used to capture the interface between the solid bodies and the incompressible surrounding fluid, within an Eulerian approach. The mixed velocity–pressure variational formulation is established for the global coupled mechanical problem and discretized using a continuous linear approximation in both velocity and pressure. Three ways are investigated to reduce the spurious oscillations of the pressure that appear at the fluid–solid interface. First, two stabilized finite element methods are used: the MINI‐element and the algebraic subgrid method. Second, the surface integral corresponding to the surface tension term is treated either by the continuum surface force technique or by a surface local reconstruction algorithm. Finally, besides the direct evaluation method proposed by Bruchon et al., an alternative method is proposed to avoid the explicit computation of the surface curvature, which may be a source of difficulty. These different issues are addressed through various numerical examples, such as the two incompressible fluid flow, the elastic inclusion embedded into a Newtonian fluid, or the study of a granular packing. Copyright © 2012 John Wiley & Sons, Ltd.