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101.
张玉林 《南京师大学报(自然科学版)》1997,20(1):86-89
进入90年代以来,国内大多数宾馆先后开发了各自的宾馆管理信息系统,实现了计算机管理,这类HMIS对于改善宾馆服务质量,促进现代化是非常重要的。本文结合作者开发宾馆服务软件的实践,论证了开发宾馆决策支持系统的客观必然性,提出了面向宾馆决定支持系统的架结构及有关的研究思路,并给出研制工作中的几点建议和结论。 相似文献
102.
旅游饭店经营业绩评价系统研究 总被引:2,自引:0,他引:2
本文运用系统层级理论构建了旅游饭店经营业绩评价模式,运用灰色系统和模糊数学的理论与方法,提出了一种新的定性与定量相结合的评价程序,并给出了一个算例. 相似文献
103.
Philip Fraundorf 《Complexity》2008,13(3):18-26
Bayesian maxent lets one integrate thermal physics and information theory points of view in the quantitative study of complex systems. Since net surprisal (a free energy analog for measuring “departures from expected”) allows one to place second law constraints on mutual information (a multimoment measure of correlations), it makes a quantitative case for the role of reversible thermalization in the natural history of invention, and suggests multiscale strategies to monitor standing crop as well. It prompts one to track evolved complexity starting from live astrophysically observed processes, rather than only from evidence of past events. Various gradients and boundaries that play a role in availability flow, ranging from the edge of a wave‐packet to the boundary between idea‐pools, allow one to frame wide‐ranging correlations (including that between a phenomenon and its explanation) as delocalized physical structures. © 2007 Wiley Periodicals, Inc. Complexity, 2008 相似文献
104.
针对传统方法预测冲击地压存在的弊端,采用遗传算法设计的模糊神经网络做为预测模型,为避免传统遗传算法"早熟"问题而使用生态遗传算法对该模糊神经网络进行训练,选择Matlab7.01在PC机上实现该网络模型,并比较BP算法、传统遗传算法以及生态遗传算法这三种算法所训练的网络性能.仿真和实验结果显示生态遗传算法使网络具有良好的收敛性能,提高了冲击地压预测的准确性. 相似文献
105.
Jeroen Bruggeman Breanndán Ó Nualláin 《Computational & Mathematical Organization Theory》2000,6(2):161-170
Niche width theory, a part of organizational ecology, predicts whether specialist or generalist forms of organizations have higher fitness, in a continually changing environment. To this end, niche width theory uses a mathematical model borrowed from biology. In this paper, we first loosen the specialist-generalist dichotomy, so that we can predict the optimal degree of specialization. Second, we generalize the model to a larger class of environmental conditions, on the basis of the model's underlying assumptions. Third, we criticize the way the biological model is treated in sociological theory. Two of the model's dimensions seem to be confused, i.e., that of trait and environment; the predicted optimal specialization is a property of individual organizations, not of populations; and, the distinction between fine and coarse grained environments is superfluous. 相似文献
106.
Resource partitioning theory claims that Increasing concentration enhances the life chances of specialist organizations. We systematically think through this theory, specify implicit background assumptions, sharpen concepts, and rigorously check the theory's logic. As a result, we increase the theory's explanatory power, and claim—contrary to received opinion'that under certain general conditions, resource partitioning and the proliferation of specialists can take place independently of organizational mass and relative size effects, size localized competition, diversifying consumer tastes, increasing number of dimensions of the resource space, and changing niche widths. Our analysis makes furthermore clear that specialist and generalist strategies are asymmetric, and shows that not concentration enhances the life chances of specialists but economies of scale instead. Under the conditions explicated, we argue that if scale economies come to dominate, the number of organizations in the population increases, regardless of the incumbents' sizes. 相似文献
107.
具有生态位构建作用的种群进化动力学模型及其应用研究 总被引:3,自引:0,他引:3
依据进化动力学的理论与方法,系统探讨了生态位构建的机理与模式.通过建立生态位构建的空间模式及其适合度计算公式和具有生态位构建作用的单种群与两种群的进化动力学模型,并对其种群进化动态、种间竞争共存机制进行的理论与数值模拟分析,揭示了生物与环境资源的协同进化关系.结果表明:种群动态受其主要生态因子及资源含量的正反馈作用.生态位构建作用通过对种群适宜度的影响而产生进化响应.单种群动力系统存在种群大小的阈值效应;在两竞争种群动力系统中,生态位构建可以导致进化动力系统的多个竞争结果,从而为解释种间竞争与稳定共存提供了一种新的理论机制. 相似文献
108.
从顾客让渡价值角度出发,对西宁市家庭宾馆发展现状进行了调查研究,结果显示,目前西宁市家庭宾馆具有经营方式多样化、产品形态以短期租赁为主的特点,同时也存在地理位置不佳、服务项目单一、入住管理不完善和服务质量不高等问题。据此,提出明确市场定位、开发个性化产品、注重全面质量营销、提升顾客和员工满意度以及不断完善行业相关规定和标准等对策。 相似文献
109.
采用Levins、Hurlbert、Pianka公式,对安徽黄山、浙江天目山、浙江白云山、江西庐山4个地区的迎春樱群落进行了生态位分析,结果表明:不同地区群落中迎春樱具较高的生态位宽度,其Levins和Hurlbert生态位宽度的测度结果均列各群落第一,4个地区种群两种生态位宽度值分别为0.632、0.654,0.721、0.748和0.664、0.833,0.734、0.849,迎春樱在群落中具有一定的优势,对资源利用充分,具有较强的环境适应性;从Pianka生态位重叠值来看,生态位重叠值≥0.6的种,在安徽黄山、浙江天目山、江西庐山、浙江白云山迎春樱群落所占比例分别为52.78%、42.86%、36.11%、60.00%,不同地区迎春樱群落生态位重叠值较高,种间竞争激烈,迎春樱多被排挤于林缘或疏林下,在人为干扰破坏剧烈的地段,种群有衰退的趋势。 相似文献
110.
A hybrid sequential niche algorithm is used for the automated identification of critical points of velocity fields. This method combines an adaptive sequential niche technique with deterministic local optimization to detect critical points: focus, node and saddle points. A particle swarm algorithm performs a global search whereas vortex core identification functions compute the precise location as the extremum of the corresponding function. Once a critical point is found, a rectangular niche is constructed around the point. The particle swarm then proceeds to explore different regions of the velocity field. The process advances sequentially, avoiding areas near previously found critical points by blocking niches obtained from previous steps. The niche size is automatically adjusted each time a search enters inside an existing niche. Vortex core functions are used for critical point identification and calculating its precise location inside each niche. The procedure is validated on particle image velocimetry data obtained with two types of flows, an impinging jet flow and a flow downstream of a model building. The hybrid algorithm proved to be very efficient and robust for automated detection and identification of critical points. It can be used as a first step for studying the time‐dependent dynamic behavior of instantaneous velocity fields by tracking topological critical points. This is the first study that uses a multi‐modal particle swarm algorithm for critical point identification. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献