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101.
阐述了在跌落冲击试验时主冲击与次冲击的特点 ;计算了产品模型对一个单次冲击循环的响应 ,分析了产品损坏的原因。当产品进行精密冲击试验时 ,消除次冲击是很有必要的。  相似文献   
102.
针对业界GPRS/EDGE无线数据优化方法、算法不完善,工作效率低的问题,广西联通通过长期研究建立了一套优化经验方法和较适合现网的参数配置、算法,并将这套方法、算法应用到自主开发的无线数据业务智能优化系统中,使系统实现自动采集分析数据、自动提供优化方案、自动执行优化方案、自动生成优化报告功能,使无线数据业务优化工作朝着智能化方向迈进。  相似文献   
103.
Mitochondrial Complex II is composed of four core subunits and mutations to any of the subunits result in lowered Complex II activity. Surprisingly, although mutations in any of the subunits can yield similar clinical outcomes, there are distinct differences in the patterns of clinical disease most commonly associated with mutations in different subunits. Thus, mutations to the SdhA subunit most often result in mitochondrial disease phenotypes, whilst mutations to the other subunits SdhB-D more commonly result in tumour formation. The reason the clinical outcomes are so different is unknown. Here, we individually antisense-inhibited three of the Complex II subunits, SdhA, SdhB or SdhC, in the simple model organism Dictyostelium discoideum. Whilst SdhB and SdhC knockdown resulted in growth defects on bacterial lawns, antisense inhibition of SdhA expression resulted in a different pattern of phenotypic defects, including impairments of growth in liquid medium, enhanced intracellular proliferation of the bacterial pathogen Legionella pneumophila and phagocytosis. Knockdown of the individual subunits also produced different abnormalities in mitochondrial function with only SdhA knockdown resulting in broad mitochondrial dysfunction. Furthermore, these defects were shown to be mediated by the chronic activation of the cellular energy sensor AMP-activated protein kinase. Our results are in agreement with a role for loss of function of SdhA but not the other Complex II subunits in impairing mitochondrial oxidative phosphorylation and they suggest a role for AMP-activated protein kinase in mediating the cytopathological outcomes.  相似文献   
104.
本文采用协方差描述函数技术(CADET)对某型反舰导弹制导段进行了统计分析,构造了制导段的統计分析模型,解决了CADET方法应用中的一些实际问题,提供了研究随机控制系统的实用、有效分析程序。实例计算表明:方法简便、程序可靠、结果正确。  相似文献   
105.
In analyses of protein families that may serve as drug targets, membrane-associated G-protein-coupled receptors (GPCRs) dominate, followed by ion channels, transporters, and—to a lesser extent—membrane-bound enzymes. However, various challenges put such membrane proteins among key groups of underutilized opportunities for the application of therapeutic antibodies. Antibodies hold the promise of exquisite specificity, as they are able to target even specific conformations of a particular membrane protein, as well as adaptability through engineering into various antibody formats. However, the ease of raising and isolating specific, effective antibodies targeting membrane proteins depends on many factors. In particular, the generation of specific antibodies is easier when targeting larger, simpler, extracellular domains with greater uniqueness of amino acid sequence. The rareness of such ideal conditions is illustrated by the limited number of approved biologics for targeting GPCRs and other complex membrane proteins. Challenges in developing antibodies to complex membrane proteins such as GPCRs, ion channels, transporters, and membrane-bound enzymes can be addressed by the design of the antigen, antibody-generation strategies, lead optimization technologies, and antibody modalities. A better understanding of the membrane proteins being targeted would facilitate mechanism-based drug discovery. This review describes the advantages and challenges of targeting complex membrane proteins with antibodies and discusses the preparation of membrane protein antigens and antibody generation, illustrated by select examples of success.  相似文献   
106.
It is suggested that biological systems provide the best source of paradigms for the consideration of the kinds of organizations which we find in human systems; social, political or economic. A brief review of the several ways in which biological activities can be mathematically modelled is given, together with indications of the manner in which these ideas can be extended and applied beyond biology.  相似文献   
107.
本文介绍的虚拟实务培训系统基于有限状态机思想,利用状态跳转的思想简化虚拟培训系统的实现逻辑,并选用FLEX、数据库技术对系统在技术上进行了实现。  相似文献   
108.
Variable-order fractional derivatives and their numerical approximations   总被引:1,自引:0,他引:1  
This paper addresses the different possible definitions of variable-order derivatives and their numerical approximations; both approximations based upon the definitions and approximations consisting of non-linear transfer functions (in particular combining existing approximations of constant-order fractional derivatives, such as the Crone approximation, with fuzzy logic) are considered. There are different possible configurations, implementing variable-order fractional derivatives both with and without memory of past values of the time-dependent differentiation order.  相似文献   
109.
李晓军 《中国电梯》2011,(12):70-72
从收集电梯成品箱供应商运输.库存,发运三个环节存在的问题做为切人点.从提高效率.提高发运产能优化流程等方面考虑.设计。电梯发运管理”辅助软件——电梯发运排队叫号系统。  相似文献   
110.
介绍中国联通采购管理系统建设面临的业务现状、问题、系统的解决方案,并对系统的应用价值进行了分析,提出未来发展的展望。  相似文献   
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