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71.
目的针对高龄重听血管性痴呆患者交流困难,设计改进型MMSE电子课件评估其积分,并观察小剂量盐酸多奈哌齐与养血清脑颗粒联合应用对本类患者的疗效。方法将60例69岁以上伴有听力障碍的血管性痴呆患者随机分成两组:联合治疗组30例均应用盐酸多奈哌齐5mg,每晚1次,并用养血清脑颗粒,每次4g,2次/d;对照组30例仅服用盐酸多奈哌齐5mg,每晚1次。疗程均3个月。结果治疗后两组患者的临床症状均有所减轻,记忆能力改善,且联合治疗组疗效优于对照组(P<0.05)。结论改进型MMSE量表为耳聋患者的评估提供了方便实用有效的手段,小剂量盐酸多奈哌齐联合养血清脑颗粒相比单一药物治疗对高龄血管性痴呆患者有更好效果。  相似文献   
72.
Inference in hybrid Bayesian networks using dynamic discretization   总被引:1,自引:0,他引:1  
We consider approximate inference in hybrid Bayesian Networks (BNs) and present a new iterative algorithm that efficiently combines dynamic discretization with robust propagation algorithms on junction trees. Our approach offers a significant extension to Bayesian Network theory and practice by offering a flexible way of modeling continuous nodes in BNs conditioned on complex configurations of evidence and intermixed with discrete nodes as both parents and children of continuous nodes. Our algorithm is implemented in a commercial Bayesian Network software package, AgenaRisk, which allows model construction and testing to be carried out easily. The results from the empirical trials clearly show how our software can deal effectively with different type of hybrid models containing elements of expert judgment as well as statistical inference. In particular, we show how the rapid convergence of the algorithm towards zones of high probability density, make robust inference analysis possible even in situations where, due to the lack of information in both prior and data, robust sampling becomes unfeasible.  相似文献   
73.
Outsourcing stretches supply chains longer with added contract manufacturers responsible for the manufacturing of parts and final products. Should a firm change its quality management approach as its supply chain becomes longer with outsourced manufacturing? This paper studies a brand owner's optimal choice between two commonly used quality management approaches: an inspection‐based approach and an external failure‐based approach, in two supply chains – a dyadic supply chain and a multi‐level supply chain where the brand owner outsources manufacturing to an independent contract manufacturer. Our study finds that the brand owner's optimal choice between the two quality management approaches could be opposite in the two supply chains. Specifically, we show that if agency costs exist between the contract manufacturer and the brand owner, the brand owner may prefer an inspection‐based approach in the multi‐level supply chain in contrast to preferring an external failure‐based approach in the dyadic supply chain. In particular, inspections can be effective for the brand owner to limit the manufacturer's profit by excluding defective finished products and components, which in turn reduce agency costs in the multi‐level supply chain. Hence, the efficiency of an inspection‐based approach relative to an external failure‐based approach can be higher in the multi‐level supply chain as compared to the dyadic one. Our findings suggest that firms should adjust to changes in supply chain structures and re‐evaluate the efficiencies of different quality management approaches accordingly.  相似文献   
74.
In a technology project, project integration represents the pooling together of complete, interdependent task modules to form a physical product or software delivering a desired functionality. This study develops and tests a conceptual framework that examines the interrelationships between the elements of work design, project integration challenges, and project performance. We identify two distinct elements of work design in technology projects: (i) the type of project organization based on whether a technology project spans a firm boundary (Domestic‐Outsourcing) or a country boundary (Offshore‐Insourcing) or both boundaries (Offshore‐Outsourcing) or no boundaries (Domestic‐Insourcing), and (ii) the joint coordination practices among key stakeholders in a technology project—namely, Onsite Ratio and Joint‐Task Ownership. Next, we measure the effectiveness of project integration using integration glitches that capture the incompatibility among interdependent task modules during project integration. Based on analysis of data from 830 technology projects, the results highlight the differential effects of distributed project organizations on integration glitches. Specifically, we find that project organizations that span both firm and country boundaries (Offshore‐Outsourcing) experience significantly higher levels of integration glitches compared to domestic project organizations (Domestic‐Outsourcing and Domestic‐Insourcing). The results further indicate that the relationship between project organization type and integration glitches is moderated by the extent of joint coordination practices in a project. That is, managers can actively lower integration glitches by increasing the levels of onsite ratio and by promoting higher levels of joint‐task ownership, particularly in project organization types that span both firm and country boundaries (Offshore‐Outsourcing). Finally, the results demonstrate the practical significance of studying integration glitches by highlighting its significant negative effect on project performance.  相似文献   
75.
对中国27个省、自治区、直辖市的软件和信息技术服务业创新效率及其影响因素进行了测度。在2009—2012年,软件和信息技术服务业创新效率的提升主要依靠增加研发人员的数量,中国东部地区该产业的创新效率高于中西部,并且产业开放度对其创新产出有负向影响,市场结构和企业规模对其具有正向影响。研究结果表明,该产业的创新效率还具有很大提升空间。  相似文献   
76.
搭售是反垄断法重点规制的对象,在反垄断史上一直被视为“本身违法”行为。软件搭售是随着软件产业的发展及反垄断法对软件产业的干预而出现的新概念,旨在强调软件产业中的搭售与传统产业中搭售的区别。软件搭售违法性的认定难题主要在于独立产品的认定,即两种被捆绑在一起的软件是集成产品还是两个独立的产品。欧美司法实践一般根据消费者需求来进行判断,即消费者需求标准,这是值得我国反垄断执法和司法借鉴的。  相似文献   
77.
连续化生产的管道由于压力、腐蚀、冲击等不良工况的影响,在异径管道的异径段经常发生物料的泄漏等现象, 给生产带来隐患。通过分析注剂力对传统异径夹具轴向的影响,对传统夹具进行结构的优化,设计出新型夹具,使之沿 轴向的位移力减小,不产生轴向位移。并且通过ANSYS的应力验证,新型结构形式的夹具能有效延长夹具寿命,保证生 产装置长久安全运行。  相似文献   
78.
为实现零组件的智能装配设计,提出了基于CATIA二次开发的零组件智能装配的方法。通过对模型装配元素 进行发布,查找装配特征,创建装配基准和参考元素并自动建立装配约束,实现在CATIA环境下同批号零组件的智能装 配,大大减轻了设计人员的工作强度,提高了装配效率,缩短了产品开发周期。该研究在实践中取得了很好的应用效果。  相似文献   
79.
精确地估算软件成本是软件项目成功开发的一个重要保证,直接影响着软件的风险控制和质量保证.为了更好地解决单一估算模型的不足,提出了集成多案例推理(CBR)模型的软件成本组合估算模型.首先,采用六种距离计算公式刻画新旧项目相似度,构建了六种CBR模型,并运用粒子群算法(PSO)来优化CBR模型族中的属性权重.其次,在CBR模型族的基础上,运用支持向量回归机(SVR)模型将不同CBR模型的估算结果进行集成,提高软件成本估算结果的精度.利用Deshamais数据库对模型有效性进行检验,实证结果表明,在六种CBR模型中Euc-CBR、Min-CBR、Gau-CBR和Mah-CBR模型估算结果没有明显差异,Gre-CBR和Man-CBR模型略优;提出的SVR组合估算模型估算精度明显优于单CBR模型和其他线性组合估算模型,能有效提高软件成本的估算精度.  相似文献   
80.
围绕微积分学习中涉及数列的极限、函数的泰勒展开式和傅立叶展开式等几个基本方面,论述如何利用数学软件mathematica进行辅助教学,达到深刻而形象的理解微积分教学中较为复杂的数学概念及数学现象的目的,从而激发学生学习兴趣,促进微积分学习.  相似文献   
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