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71.
72.
Ecosystems are formed by organisations that jointly create a value proposition that a single firm could not create in isolation. To deliver this value proposition, the partners need a focal firm, the orchestrator, to be align them towards the joint value proposition. Thus, how orchestrators design the alignment structure of an ecosystem is at the very heart of the ecosystem concept – yet it has not been sufficiently addressed by extant research. This is all the more true for the question of how the design of an ecosystem is shaped depending on surrounding conditions. This paper applies a qualitative study with ten cases and, based on the attention-based view of the firm, contributes to research on ecosystems in several ways. First, it explains which ecosystem designs are beneficial under which conditions. Second, it elucidates the structure and activities within ecosystems and shows that start-ups can be just as good ecosystem orchestrators as incumbents. Third, it explains the circumstances under which single vs. multi orchestrator ecosystems occur. Fourth, it presents the conditions when incumbents or start-ups make better orchestrators. Finally, it is among the first studies to apply the attention-based view to business ecosystems, and shows that doing so yields intriguing insights into this emerging field of research. 相似文献
73.
城市医疗废弃物日益增加,且回收需求量受诸多因素的影响,难以准确预测,假定回收需求为确定值的医疗废弃物网络优化设计不能与实际需求相匹配。本文考虑了离散随机参数环境下,医疗回收网络设计中选址规划、分配计划及运输规划的协同优化问题,建立了以选址成本、运输成本最小为目标,设施与车辆能力限制为约束的二阶段随机规划模型。根据模型特点,设计了基于Benders decomposition的求解算法,同时,设计了一系列加速技术用于提高算法的求解效率。最后,以国内某城市医疗回收网络为背景设计算例,检验本文模型和求解策略的可行性和有效性。结果表明:相比确定性规划,随机规划的解能够节约总成本,结合一系列加速技术的Benders decomposition方法比CPLEX与纯的Benders decomposition更有优势。 相似文献
74.
我国高校教师薪酬在计划经济时期以平均分配为价值取向,在市场经济时期以效率为价值取向。在中国特色社会主义新时代和知识经济时期,鼓励知识创新和兑现知识价值成为新的取向。我国高校现行岗位绩效工资制度虽然将教师的实际贡献与薪酬分配联系了起来,但也存在薪酬结构缺陷、薪酬测量失真、薪酬激励偏移和薪酬调整滞后等问题。与岗位绩效工资相比,按“知”分配的3P-M薪酬模型改进了人力资本薪酬(P1),以补偿教师人力资本的前期投入、当期追加和后期增值;调整了岗位薪酬(P2),通过强化保障性薪酬以轧平薪酬曲线斜率;优化了绩效薪酬(P3),以解决教师多任务“委托—代理”的契约设计问题;新增了市场薪酬(M),以补偿因内部薪酬总量不足给教师带来的潜在损失。其中,3P重在盘活存量,M重在扩充增量,两者共同构成了3+X薪酬体系。 相似文献
75.
Summary Letg(x) andf(x) be continuous density function on (a, b) and let {ϕj} be a complete orthonormal sequence of functions onL
2(g), which is the set of squared integrable functions weighted byg on (a, b). Suppose that
over (a, b). Given a grouped sample of sizen fromf(x), the paper investigates the asymptotic properties of the restricted maximum likelihood estimator of density, obtained by
setting all but the firstm of the ϑj’s equal to0. Practical suggestions are given for performing estimation via the use of Fourier and Legendre polynomial series.
Research partially supported by: CNR grant, n. 93. 00837. CT10. 相似文献
76.
Implementing partial least squares 总被引:2,自引:0,他引:2
M. C. Denham 《Statistics and Computing》1995,5(3):191-202
Partial least squares (PLS) regression has been proposed as an alternative regression technique to more traditional approaches such as principal components regression and ridge regression. A number of algorithms have appeared in the literature which have been shown to be equivalent. Someone wishing to implement PLS regression in a programming language or within a statistical package must choose which algorithm to use. We investigate the implementation of univariate PLS algorithms within FORTRAN and the Matlab (1993) and Splus (1992) environments, comparing theoretical measures of execution speed based on flop counts with their observed execution times. We also comment on the ease with which the algorithms may be implemented in the different environments. Finally, we investigate the merits of using the orthogonal invariance of PLS regression to improve the algorithms. 相似文献
77.
分析了城市景观的主要特征和城市(城镇)交通景观的结构和功能。强调了城市景观的保护和规划管理。初步分析了城市交通廊道系统的景观生态功能。探讨了城市交通景观生态的设计原则。以江南水乡为例,分析讨论了几种城市交通景观生态设计模式。 相似文献
78.
Robert Aslett Robert J. Buck Steven G. Duvall Jerome Sacks & William J. Welch 《Journal of the Royal Statistical Society. Series C, Applied statistics》1998,47(1):31-48
In electrical engineering, circuit designs are now often optimized via circuit simulation computer models. Typically, many response variables characterize the circuit's performance. Each response is a function of many input variables, including factors that can be set in the engineering design and noise factors representing manufacturing conditions. We describe a modelling approach which is appropriate for the simulator's deterministic input–output relationships. Non-linearities and interactions are identified without explicit assumptions about the functional form. These models lead to predictors to guide the reduction of the ranges of the designable factors in a sequence of experiments. Ultimately, the predictors are used to optimize the engineering design. We also show how a visualization of the fitted relationships facilitates an understanding of the engineering trade-offs between responses. The example used to demonstrate these methods, the design of a buffer circuit, has multiple targets for the responses, representing different trade-offs between the key performance measures. 相似文献
79.
空间光通信ATP系统设计分析 总被引:2,自引:0,他引:2
空间光束捕获、跟踪、瞄准(ATP)技术在空间光通信中具有重要地位。文中讨论了空间光通信系统中的ATP伺服系统的结构,并对系统稳态设计和系统动态综合等关键问题进行了详细的分析和研究。 相似文献
80.