Familial database search on two-person mixture

This work presents how the familial database search can be applied to forensic investigations in which the DNA evidence is a mixture. The forensic identification is based on a ranked list of the likelihood ratios for each candidate in the DNA database of being the relative of the contributor of the forensic sample. A simulation study using Hong Kong Chinese data demonstrated the comparable effectiveness of our approach that in 90% of the cases, the sibling of the contributor can be found in the top 50 profiles, and the parent/child can be found in the top 10 profiles. We also discuss the prediction on the performance of the search that can guide the decision of the police force to initiate the investigation.     

Manual card sorting compared to automatic card presentation for assessing visual lobe size

Abstract

Using a sample of 54 Hong Kong Chinese subjects a highly significant correlation was found between lobe area and search performance on a task where the stimulus presentation was controlled with a semi-automatic electro-mechanical ‘card changer’. By using the same stimulus material for determination of lobe size and search performance and by reducing the possibility of subjects using extreme search strategies, a 90s manual card sorting test was found to correlate significantly with the ‘card changer’ results and with lobe area. The good correlation with lobe area was obtained for a homogeneous group of subjects with respect to age and near acuity using a rapid and simple method of lobe area measurement. The visual lobe is a function of considerable importance for visual search and has been shown to be related to search performance in a variety of practical situations. It is suggested here that a card sorting task may be used to assess the relative extent of a person's visual lobe size for screening individuals involved in search tasks, or to assess the effects of training.     

Novel dynamic semiempirical proton exchange membrane fuel cell model incorporating component voltages

This paper introduces a novel dynamic semiempirical model for the proton exchange membrane fuel cell (PEMFC). The proposed model not only considers the stack output voltage but also provides valid waveforms of component voltages, such as the no‐load, activation, ohmic, and concentration voltages of the PEMFC stack system. Experiments under no‐load, ramping load, and dynamic load conditions are performed to obtain various voltage components. According to experimental results, model parameters are optimised using the lightning search algorithm by providing valid theoretical ranges of parameters to the lightning search algorithm code. In addition, the correlation between the vapour and water pressures of the PEMFC is obtained to model the component voltages. Finally, all component voltages and the stack output voltage are validated by using the experimental/theoretical waveforms mentioned in previous research. The proposed model is also compared with a recently developed semiempirical model of PEMFC through particle swarm optimisation. The proposed dynamic model may be used in future in‐depth studies on PEMFC behaviour and in dynamic applications for health monitoring and fault diagnosis.     

Fast string matching for multiple searches

We present a string matching or pattern matching method which is especially useful when a single block of text must be searched repeatedly for different patterns. The method combines linking the text according to digrams, searching on the least‐frequent digram, and probing selected characters as a preliminary filter before full pattern comparison. Tests on real alphabetic data show that the number of character comparisons may be decreased by two orders of magnitude compared with Knuth–Morris–Pratt and similar searching, but with an initialization overhead comparable to five to ten conventional searches. Copyright © 2001 John Wiley & Sons, Ltd.     

不同比转速(n_(s_1)、n_(s_2))泵叶轮的同轴串联试验研究

本文论述了不同比转速(n:1、n:2)泵叶轮进行同轴串联的有关问题。通过对性能参数的选择与匹配计算、水力设计问题的处理,样机试验及真机的运行考核,其问题得到了满意的解决。     

约束变尺度法应用探讨

约束变尺度法是一个有效地求解约束问题的最优化方法，但对实际工程中存在的诸如函数不可导及函数求值复杂等非理想情况，求解尚有不少具体困难．本文从应用角度出发，对该方法作了改进，通过适当选择差商形式和对一维不精确线性搜索方法的修正，提高了该方法的适用范围，并保持了其函数计算次数少和收敛速度快的特点．通过检验函数和实际问题的计算，证明改进的算法方便有效且具有较高的稳定性和普遍适用性．     

无约束最优化问题的特征值方法

本文讨论了利用变量变换求解二次可微函数ｆ（ｘ）的无约束最优化问题，给出了一个特征值方法，解决了Ｈｅｓｓｅ阵非正定时的搜索方向问题。实算表明，该算法在迭代次数和数值稳定性上均令人满意。     

线性目标规划的解结构分析及遍历算法设计

从一实例分析出发，推导出一般线性目标规划数学模型的多重解结构为一无向图。进而介绍了广度优先搜索多重解图的遍历算法，并为求得各个多重解设计了一种便于实施的计算机数据结构与算法。     

一种约束非线性离散优化问题的直接搜索法

本文针对整数梯度搜索方向的局部性以及有时因取整而方向发散的缺点,提出了在离散设计空间中,利用离散坐标邻域点的目标函数值信息和适当的延伸探索直接构造离散搜索方向,并进行离散一维搜索的寻优方法,对此称之为离散直接搜索法(A Discrete Direct Search Method),简称DDSM法。本文运用DDSM法成功地解决了14个工程考题和数学考题,实践表明:DDSM法的求解速度和可靠性比较令人满意,尤其是计算效率相对现有的某些离散优化方法有较明显的提高。     

布尔代数模式搜索技术——一种新的启发式推理方法

简要地评述了现代的搜索技术,指出了其主要弱点;提出一种快速、高效的搜索技术——布尔代数模式搜索,列出了有关的4个子命题,并举例逐一加以说明。综合得到的命题是:在具备相应启发信息的条件下,状态空间内的搜索过程从问题求解的角度看去同构于一个布尔代数。