离心叶轮回转S1流面流动数值计算方法探讨

采用贴体坐标下的有限差分法计算了离心泵叶轮回转S1流面流动,并用试验结果进行了验证,发现了流层厚度对流动数值计算有重要影响.     

样本筛选与操作优化的可视化方法实现

可视化方法通过将多维空间数据映射到二维平面上，依据“物以聚类”属性对二维平面中各样本点进行分类、识别，找出离群样本并将其剔除掉．与此同时，产生目标函数等值线．沿着等值线值增大或减小的趋势方向寻优，就很容易地确定出最优点或最优化操作区域．以某卷烟厂生产烟丝为例进行分析和计算，结果表明，文中筛选样本数据方法中，离群点的剔除提高优化结果的准确度。最佳操作条件的确定可为工业生产或科学实验提供决策支持。     

软基沉降计算中压缩层厚度确定方法探讨

沿海地区平原水网区高速公路的软土路基，其压缩层范围与应力控制法确定的深度通常相差很大．而与应变控制法确定的厚度比较吻合．规范规定的应力控制比值与一些实际情况不符，对大宽度路基条件下的软基不太适用，导致用应力控制法计算出的沉降量比实际沉降大许多．文中结合工程实例，研究出现这一问题的机理，并给出建议．     

街道色彩景观规划的控制模式

街道色彩景观是城市设计的重要内容．文中以色彩理论为框架，对影响城市街道色彩景观的诸多因素进行分析．提出对街道色彩景观规划的若干控制模式和方法，用以指导城市街道色彩景观的规划设计．     

道路交通安全评价方法

为了准确的得进行道路交通安全评价。在分析国内外道路交通安全现状的基础上，对影响道路交通安全的影响因素进行了分析，重点评述了绝对数法、事故率法、事故强度分析法，概率一数理统计法、模型法、时间序列分析法和灰色评价方法等国内外道路交通安全的各种评价方法，指出了各种评价方法的优缺点及其适用性，结果对道路交通安全评价有一定的参考价值。     

宗地地价模糊评估的研究

论述模糊综合评估法的数学模型、指标体系及模糊集合.在理论上利用模糊变换原理和最大隶属度原则将模糊综合评估法用于宗地地价评估,结合土地资产价值的评估实例提出概念,建立数学模型和影响宗地地价因素的指标体系,并以具体实例说明模糊评估法进行宗地地价运算的全过程.这样做避免了地价评估人员的主观性、片面性,使宗地地价评估更加科学、公正.     

组合数丢番图方程[2x]=[4y]的正解

运用递推序列法，给出组合数丢番图方程[x2]=[y4]的一个初等解法．     

An on-line scaling method for improving scalability of a database cluster

The explosive growth of the Internet and database applications has driven database to be more scalable and available，and able to support on-line scaling without interrupting service. To support more client’s queries without downtime and degrading the response time，more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use，i.e.，we decrease the number of data copy by reusing te backup data. Also，our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.     

Resin Matrix/Fiber Reinforced Composite Material,Ⅲ:Simulating Results

According to the mathematical model which describes the curing process of composites constructed from continuous fiber-reinforced, thermosetting resin matrix prepreg materials, and the consolidation of the composite, the computer code calculates the data of the process variables of the flat-plate composites cured by a specified cure cycle, provides the variation of temperature distribution, the cure degree process, the resin variation and fibers stress inside the composite, the void variation and the residual stress distribution. The mechanism of curing process is illustrated and the cure cycle of composite material is optimized.     

A Theoretical Approach for Estimating Fracture Toughness of Ductile Metals

Fracture toughness is very important when applying Damage Tolerance Design and Assessment Techniques. The traditional testing approach for obtaining fracture toughness values is costly and time consuming. In order to estimate the fracture toughness of ductile metals, the fracture mechanics theory, materials plastic deformation theory and materials constructive relationships are employed here. A series of formulae and a theoretical approach are presented to calculate fracture toughness values of different materials in the plane stress and plane strain conditions. Compared with test results, evaluated values have a good agreement.