某星载电子设备的动态响应分析

随机振动分析是星载电子设备动力响应分析的重要组成部分.通过对电子设备的实体模型简化处理,建立分析模型,利用有限元分析的方法获得随机振动载荷作用下设备各部位的加速度均方根值等系列响应值,为电路板器件布局优化,整机强度、刚度优化提供参考.进行了随机振动试验,实测典型位置的加速度均方根值,对有限元分析模型参数选择的合理性以及分析结果的准确性进行验证.     

梅钢1420mm冷轧机液压压下系统的设计计算

液压压下系统是现代高速冷连轧机的核心设备。在梅山钢铁公司1420 mm酸轧机组自主集成建设过程中,根据产品的质量和生产要求,在对以往引进轧机压下系统深入剖析的基础上,通过理论计算最终确定了压下缸、伺服阀的型号,以此为重点完成了1420 mm轧机液压压下系统的设计,并在随后的调试和使用中验证,达到了设计效果。     

Dilution: A theoretical burden or just load? A reply to Tsal and Benoni (2010).

Load theory of attention proposes that distractor processing is reduced in tasks with high perceptual load that exhaust attentional capacity within task-relevant processing. In contrast, tasks of low perceptual load leave spare capacity that spills over, resulting in the perception of task-irrelevant, potentially distracting stimuli. Tsal and Benoni (2010) find that distractor response competition effects can be reduced under conditions with a high search set size but low perceptual load (due to a singleton color target). They claim that the usual effect of search set size on distractor processing is not due to attentional load but instead attribute this to lower level visual interference. Here, we propose an account for their findings within load theory. We argue that in tasks of low perceptual load but high set size, an irrelevant distractor competes with the search nontargets for remaining capacity. Thus, distractor processing is reduced under conditions in which the search nontargets receive the spillover of capacity instead of the irrelevant distractor. We report a new experiment testing this prediction. Our new results demonstrate that, when peripheral distractor processing is reduced, it is the search nontargets nearest to the target that are perceived instead. Our findings provide new evidence for the spare capacity spillover hypothesis made by load theory and rule out accounts in terms of lower level visual interference (or mere “dilution”) for cases of reduced distractor processing under low load in displays of high set size. We also discuss additional evidence that discounts the viability of Tsal and Benoni's dilution account as an alternative to perceptual load. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aerostatic Reliability Analysis of Long-Span Bridges

The response surface Monte Carlo method (RSMCM) is proposed for reliability analysis of aerostatic response and aerostatic stability for different types of long-span bridges, in which the nonlinear effects due to geometric nonlinearity and deformation-dependent aerostatic loads are taken into consideration. The geometric parameters, the material parameters, and the aerostatic coefficients of the bridge girder are regarded as random variables in the proposed method. RSMCM has higher accuracy in comparison with the traditional response surface method and requires much less computational cost than the conventional Monte Carlo method. The proposed method is applied to reliability analysis of aerostatic response and aerostatic stability of the Hong Kong Ting Kau Bridge, and reasonable results illustrating effectiveness of the method are obtained.     

Schistosome behavior in vitro

Schistosome adults attract each other in vitro and the attraction is chemically mediated. InSchistosoma mansoni adults, excretory-secretory (ES) products of worms of one sex attract worms of the opposite sex, and at least the lipophilic fraction is attractive. Intra- and interspecific attraction occurs inSchistosoma mansoni, S. japonicum, andS. haematobium adults. Current knowledge of schistosome behavior in vitro is reviewed.     

Application strategies for Sechura phosphate rock use on permanent pasture

At two phosphate (P) responsive sites in hill country the effectiveness of Sechura phosphate rock (SPR) as a direct application P fertilizer for permanent pasture was evaluated. Sechura was applied at two rates, in three different application strategies. The treatments were 16.7 and 50 kgP ha^–1 annually, 25 and 75 kgP ha^–1 biennially, and 50 and 150 kgP ha^–1 triennially giving a total of 50 and 150 kgP ha^–1, respectively, over three years. Single superphosphate (SSP) served as the standard P fertilizer. A comparison was also made between SPR and Chatham Rise phosphorite (CRP), another reactive PR. Total pasture and legume production and P uptake by pasture was measured with all fertilizer treatments over a three year period.In the year of application, SPR was as effective as SSP in stimulating total pasture and legume production and P uptake by pasture. This reflects the very reactive nature of this PR. In the second and third years of measurement, SPR did not show superior residual efffects to SSP. The ability of CRP to stimulate legume growth more than SPR in the second year following application demonstrates the danger of generalizing about the residual effects of reactive PR materials. Of the application strategies evaluated, a biennial appplication of 25 kgP ha^–1 as SPR maintained legume growth at a higher level than a smaller (16.7 kgP ha^–1) annual dressing. The biennial strategy also increased total pasture yield, in addition to legume production to a greater extent in the second and third years than a single (50 kgP ha^–1) triennial application.     

两主两从博弈下的装备维修器材供应链协调研究

以相互竞争的两条装备维修器材供应链作为研究背景,提出了一种基于Stackelberg主从博弈的激励协调模型,并通过最优反应动态思想给出求解该模型的一般思路,结合粒子群优化算法对军事算例进行仿真,对比分析供应商合作与非合作下的计算结果,供应商非合作下奖金激励策略可以有效实现供应链协调,但供应商若能实现合作,将使供应商达到利益最优化,可忽略奖金激励的影响.     

弹丸垂直侵彻陶瓷/金属复合靶板的简化模型

根据薄板在冲击载荷作用下的动力响应理论,利用能量法建立了陶瓷／金属复舍靶板抵抗小型穿甲弹侵彻的理论分析模型．在给定的靶板条件下,该模型可以模拟在冲击载荷作用下的复合靶板的弹道极限速度,并分别对铝板和钢板做背板的复合靶板进行了试验验证;同时,在相同的面密度下,比较了不同背板的抗弹效果,实验结果和数值结果吻合较好．     

脉冲载荷下柱壳结构响应实验研究

利用电子束及化爆对柱壳模拟结构进行脉冲加载，通过试验研究结构响应规律及结构破坏阈值，对壳体结构响应的基本理论进行了论述和分析；根据电子束及化爆加载实验结果，重点分析了不同结构的破坏阈值；提出了提高柱壳壳体抗脉冲载荷能力的技术途径。     

响应面法优化毛叶藜芦环巴胺的提取工艺

采用响应面法优化了从毛叶藜芦中提取环巴胺的条件。在单因素实验的基础上选取提取液料比,提取时间和提取温度为随机因子,以环巴胺提取量为响应值,建立三因素三水平Box-Behnken中心组合设计,并建立数学模型对响应值进行分析。结果表明,提取液料比、提取时间和提取温度对环巴胺的提取量都有极显著（p<0.01）的影响,并确定了最佳的提取工艺参数为:提取液料比9∶1（mL/g）,提取时间10.0h,提取温度48.0℃。在此优化条件下,提取10.0g毛叶藜芦得到环巴胺的理论量为9.38mg,实际提取量为9.19mg,相对误差为2.02%。