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51.
摘要:产品平台对于复杂工业企业取得竞争优势的重要性已经成为学者们的共识,但现有研究对于产品平台独立性差异及导致差异的机理并未做深入探讨。本文采用双案例比较研究方法,选择两家在产品平台独立性上存在较大差异的企业--大连机车与一汽轿车--进行对比分析,探讨影响企业产品技术平台独立性的主要因素及机理关系。研究发现:(1)产品-市场结构、技术战略、资源协奏模式是影响产品平台独立性差异的主要因素;(2)在产品-市场结构、技术战略的影响下,平台独立性差异企业会表现出不同的资源协奏模式--多元协奏与单一拼接。(3)产品-市场结构、技术战略与资源协奏模式之间存在密切的互动关系:产品-市场结构影响下的技术战略,及技术战略影响下的资源协奏模式最终影响平台独立性。本研究明确了不同企业在产品平台独立性方面产生差异的原因并提出了相关机理,补充了关于产品平台独立性的相关研究。 相似文献
52.
Dennis Mays 《Support for Learning》2020,35(1):83-100
The profile of a student with learning difficulties is described and also the learning context in 2017. Previous models of provision are then described in terms of their aetiology with discussion of strengths and shortcomings. Some influential features of curriculum planning and delivery are identified. A model of provision involving specific literacy teaching and differentiation is advocated. 相似文献
53.
陆栋梁 《南宁师范高等专科学校学报》2014,(2):15-20
灌阳县丧葬仪式之中的“大歌”,纳数百桩事于一体,内容博而杂;集百千言为一歌,结构长而大,此二者相辅相成,造就了包罗灌阳历史和现实,收尽生活种种现象的长大篇章,同时也造就其庞杂性特征。这一特性,当地居民用一字概而括之,谓之曰“大”。 相似文献
54.
[目的/意义]改善现有专利技术主题分析方法主题辨识度低、主题词二义性、无法识别技术信息中的"问题"与相应"解决方案"等问题。[方法/过程]本文通过抽取专利文本中的SAO结构,并从SAO结构中识别"问题和解决方案"(P&S)模式,基于"bag of P&S"假设,构建基于"主语-行为-宾语"(subject-action-object,SAO)结构的LDA主题模型,实现对专利文献主题结构的识别和分析。[结果/结论]案例研究表明,该方法能够有效识别主题分布,并在主题辨识度和语义消岐方面较传统LDA模型具有较大优势。 相似文献
55.
This article is concerned with the extended homogeneous balance method for studying the abundant lacalized solution structure of the (2 1)-dimensional asymmetric Nizhnik-novikov-Veselov equation.A Baecklund transformation was first obtained.and then the richness of the localized coherent structures was found,which was caused by the entrance of two variable-separated arbitrary functions,in the model.For some spectial choices of the arbitrary functions,it is shown that the localized structures of the model may be dromions,lumps,and rinmg solitons. 相似文献
56.
AbstractPublic Management and Public Administration are important professions for an emerging democracy such as South Africa. They operate as the interface between state and public and are responsible for enacting many of the government's policies and social initiatives. Concerns about a lack of capacity in the sector suggest that those in these roles may be unable to meet the demands of the workplace. This article reports on a study that responded to calls for the curriculum to address such concerns by interrogating the knowledge structures of Public Management and Public Administration programmes in higher education. Interviews, textbooks and course guides were analysed to illuminate the forms of knowledge being legitimated in curricula. The study found that the focus on knowledge, skills and processes might be at the expense of a focus on the development of particular attributes or dispositions in the knowers. Furthermore, the knowledge level focus was limited in that it was highly contextualised and “light” on theory, raising questions about the acquisition of powerful knowledge needed for good governance and critical engagement in the public sector. The study recommends that both programmes include more conceptual knowledge; exposure to critical powerful forms of knowledge; and the development of particular attributes and dispositions. 相似文献
57.
“A+比+B+W+Z”和“A+W+B+Z”是两种带比较差值的差比句句式,广泛分布在汉语方言中。本文探讨它们在汉语方言区中的分布情况、交替机制以及竞争状态。和“A+W+B”不同,“A+W+B+Z”普遍存留在汉语方言中,其原因有待考察。 相似文献
58.
Numerical Simulation of Dynamic Response and Collapse for Steel Frame Structures Subjected to Blast Load 总被引:4,自引:0,他引:4
The progressive collapse of steel frame structures under the blast load was investigated using LS-DYNA. The multi-material Eulerian and Lagrangian coupling algorithm was adopted. A flu-id-structure coupling finite element model was established which consists of Lagrange element for simulating steel frame structures and concrete ground, multiple ALE element for simulating air and TNT explosive material. Numerical simulations of the blast pressure wave propagation, struc-tural dynamic responses and deformation, and progressive collapse of a five-story steel frame structure in the event of an explosion near above ground were performed. The numerical analysis showed that the Lagrangian and Eulerian coupling algorithm gave good simulations of the shock wave propagation in the mediums and blast load effects on the structure. The columns subjected to blast load may collapse by shear yielding rather than by flexural deformation. The columns and joints of steel beam to column in the front steel frame structure generated enormous plastic defor-mation subjected to intensive blast waves, and columns lost carrying capacity, subsequently lead-ing to the collapse of the whole structure. The approach coupling influence between struc-tural deformation and fluid load well simulated the progressive collapse process of structures, and provided an effective tool for analyzing the collapse mechanism of the steel frame structure under blast load. 相似文献
59.
The progressive collapse of steel frame structures under the blast load was investigated using LS-DYNA.The multi-material Eulerian and Lagrangian coupling algorithm was adopted.A fluid-structure coupling finite element model was established which consists of Lagrange element for simulating steel frame structures and concrete ground,multiple ALE element for simulating air and TNT explosive material.Numerical simulations of the blast pressure wave propagation,structural dynamic responses and deformation,and progressive collapse of a five-story steel frame structure in the event of an explosion near above ground were performed.The numerical analysis showed that the Lagrangian and Eulerian coupling algorithm gave good simulations of the shock wave propagation in the mediums and blast load effects on the structure.The columns subjected to blast load may collapse by shear yielding rather than by flexural deformation.The columns and joints of steel beam to column in the front steel frame structure generated enormous plastic deformation subjected to intensive blast waves,and columns lost carrying capacity,subsequently leading to the collapse of the whole structure.The approach coupling influence between structural deformation and fluid load well simulated the progressive collapse process of structures,and provided an effective tool for analyzing the collapse mechanism of the steel frame structure under blast load. 相似文献
60.
Optimal piezo-actuator sizes and locations for a frame structure under bending load uncertainty are determined with the objective of minimizing the deflection under worst case of loading. The bending moments generated by the piezo-actuators are used for deflection control, i.e., to minimize the maximum deflection. The frame is subjected to a tip load which lies in an uncertainty domain with regard to its magnitude and direction. The specific uncertain loading studied in the present paper involves a load of given magnitude but of unknown direction, which should be determined to produce the highest deflection. The worst case of loading depends on the size and location of the actuators leading to a nested problem of optimization (design) and anti-optimization (uncertainty problem). Results are given for deterministic and uncertain loading conditions. 相似文献