形状相似性法的圆柱斜齿轮冷锻数值模拟

提出了锻件毛坯与齿轮形状相似性冷锻法,改善成形质量,同时锻坯中心孔分流,可降低成形力.用三维有限元仿真软件数值模拟圆柱斜齿轮的闭式冷锻过程,确定下端面带凹槽的齿轮锻坯形状,该形状能避免齿轮成形产生的折叠缺陷;通过对材料变形的应变场、应力场、速度场、加载曲线等规律的分析,确定变形严重的应力区和应变最大值分布位置,指出材料成形流动速度差过大,是产生成形折叠缺陷的原因.总之,形状相似性法的圆柱斜齿轮冷锻成形齿轮是可行和有效,具有工程实际应用意义.     

求解大规模TSP问题的混合算法

遗传算法求解大规模TSP时呈现出求解时间长、后期效率明显降低等缺陷。通过结合分块方法、局部搜索算法以及禁忌算法,本文提出一个求解TSP的混合算法,以提高初始解质量,减少计算量。利用遗传算法和混合算法对几个TSP进行数值实验,表明无论在结果的质量上还是在运行效率上,混合算法都明显优于遗传算法,而且,规模越大效果越明显。     

高速瓦楞辊机构的中高度及其动挠度曲线方程

论述了高速瓦楞辊机构扣高度的动力学特片，建立了相应的上、下瓦楞辊的设计中高度的数学模型，导出对应的动挠度曲线方程。     

Theoretical consistency test of steam transport properties

The kinetic theory of polyatomic gases is used to test the mutual consistency of the thermal conductivity, viscosity and specific heat of low-pressure steam from 100° to 700°C. No inconsistency exists within the cited tolerances of the skeleton tables recommended by the Sixth International Conference on the Properties of Steam, but there is some basis for suspecting that the high-temperature thermal conductivity values are slightly low. Methods for tightening the consistency bounds are suggested.     

基于Linux系统的分权设计与实现

The secure operating system is the foundation of secure enhanced information systems. As an open source software. Linux has robust functions and good compatibilities with Unix. This paper analyzes the hidden troubles and faults in secure aspect of it. and fully discusses the design and implementation of privilege divided Linux-based sys-tem. It mainly focuses on the modifications of access control, super users' least privilege division and so on.     

The effects of divided attention on encoding processes in memory: Mapping the locus of interference.

Despite the detrimental effects of divided attention at encoding on later memory performance, results described in the literature do not unequivocally specify which processes are interrupted during encoding by participants' occupation with a concurrent task. Using a processing analysis framework where the encoding process is viewed as a multiphase mental activity, the current research investigated this issue using a new differential temporal interference paradigm where the study phase of single words was interrupted at different temporal segments. In two experiments, we used performance on both memory and online choice reaction time tasks to assess whether such differential interference would produce different degrees of reduction in participants' later memory performance, as well as changes in the attentional resources required to execute each of the encoding phases. Measures of memory and concurrent task performance in the two experiments converged on similar patterns, showing that all phases of encoding are affected by the concurrent task. However, the initial encoding phase, which is tentatively associated with the initial registration of information, seems especially vulnerable to interference. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

基于变电站九区图调节的地区电网分层无功优化

根据地区电网的实际管理模式,提出了基于变电站九区调节的地区电网分层无功优化方法:将地区电网分成次输电电网和配电网。先对次输电网进行无功优化时,将配电网等效为负荷,此时控制变量少,采用传统算法可以快速求解。在此基础上,再采用九区图方法调整配电网的无功电压,进行迭代,逐层进行无功优化直到问题收敛。实际算例表明,这种方法优化了地区电网的运行,提高了无功优化的计算速度,并且更符合实际电网的管理模式,为地区电网无功电压调节提供了有益参考。     

Near-infrared spectroscopic analysis of macronutrients and energy in homogenized meals

Near-infrared (NIR) reflectance spectroscopy was evaluated as a rapid and environmentally benign technique for the simultaneous determination of macronutrients and energy in commercially available, packaged meals. Reflectance spectra (400–2498 nm) of homogenized meals were obtained with a dispersive NIR spectrometer. Protein and moisture were measured by AOAC reference methods, total fat by a semi-automated acid hydrolysis, solvent extraction, gravimetric method and total carbohydrate calculated. Energy was calculated using Atwater factors. Using multivariate analysis software, PLS models (n = 113–115 products) were developed to relate NIR spectra of homogenized meals to the corresponding reference values. The models predicted components and energy in validation samples (n = 37–38 products), overall, with r² of above 0.96. Ratios of deviation to performance were between 3.6 and 6.6, and indicated adequacy of the models for screening, quality control, or process control. Performance of the models varied substantially when used to predict sub-groups of meals within the validation set.     

当家权的历史流变

本文从历史和村庄生活的两重维度,分别从当家权的实施者、当家权的内容、当家权与家庭形式,对当家权进行三重分析,以便理解其内在逻辑。当家权的实施者中,老人和妇女当家的逻辑是不同的,老人当家的逻辑是大家庭的理想和责任义务,而妇女当家的逻辑却更多的是小家庭的利益,从老人当家到妇女当家,其中的发生逻辑要在整个社会形势中来理解。关于当家权的内容,老人当家要服务于大家庭的理想,所进行的是家庭内部的分工协调,具有长远预期和延续性,妇女当家却更多的是服务于小家庭的利益,也可以说,老人是在当大家庭的家,而妇女在当钱的家。当家权与家庭形式关系密切,与老人当家相符的家庭形式是大家庭,妇女当家使得老人因为生存策略的考虑主动分家,家庭日益核心化,而打工经济形势下出现"未分家式的分家",这是综合了老人大家庭理想和妇女当家现实的家庭新形式。     

Process demands of rejection mechanisms of recognition memory.

A surge of research has been conducted to examine memory editing mechanisms that help distinguish accurate from inaccurate memories. In the present experiment, the authors examined the ability of participants to use novelty detection, recollection rejection, and plausibility judgments to reject lures presented on a recognition memory test. Participants studied a list of word pairs that were arranged in a category relationship (both words from the same category) or an unrelated relationship (both words from different categories) under full or divided attention. At test, participants were given a yes/no recognition test in which they were to respond after seeing the test items for 400 ms or 2,800 ms. Some of the test items were rearranged word pairs that were consistent with the study relationship, whereas others were inconsistent with the study relationship. The results demonstrate that the participants required full attention at study to use novelty detection, recollection rejection, and plausibility judgments to reject lures. Moreover, the results indicate that a long response deadline at test was needed for participants to use both recollection rejection and plausibility judgments to reject lures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)