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101.
城市RBD的成长机制与产业结构演变研究——以深圳华侨城为例 总被引:6,自引:1,他引:5
深圳华侨城是一个持续成长的休闲商务中心区的典型范例.在华侨城的成长和产业变迁过程中,休闲商务的发展具有很强的影响力.从城市边缘的华侨农场逐步发展为现代化城市中心区的RBD,华侨城演变的动力直接来源于4个方面:政策导向、市场导向、所有制导向和城市化导向. 相似文献
102.
Differentiation of the construct of emotional intelligence was investigated in young and middle-aged adults, on the basis of hypotheses generated from differential emotions theory, discrete emotions functionalist theory, and empirical literature on age-related changes in affective complexity and differentiation of abilities. Both age groups were characterized by the same set of comparably related dimensions. However, midlife adults reported significantly greater use of optimism as a mood-regulation strategy than was reported by young adults. This study considers implications of possible structural continuity in emotional intelligence in conjunction with mean increases in the use of optimism as a strategy for managing affect. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
Biological and technological systems process information by means of cascades of signals. Be they interacting genes, spiking neurons or electronic transistors, information travels across these systems, producing, for each set of external conditions, an appropriate response. In technology, circuits performing specific complex tasks are designed by humans. In biology, however, design has to be ruled out, confronting us with the question of how these systems could have arisen by accumulation of small changes. The key factor is the genotype-phenotype map. With the exception of RNA folding, not much is known about the exact nature of this mapping. Here, we show that structure of the genotype-phenotype map of simple feed-forward circuits is very close to the ones found in RNA; they have a large degree of neutrality, by which a circuit can be completely rewired keeping its input-output function intact, and there is a relatively small neighbourhood of a given circuit containing almost all the phenotypes. 相似文献
104.
Simple and accurate closed‐form formulas obtained by using a differential evolution algorithm are presented for the synthesis of coplanar waveguides (CPW). The results of the synthesis formulas proposed in this article are compared with those of the quasi‐static analysis, the synthesis formulas reported by the other researchers and also the experimental works available in the literature. The accuracy of the proposed synthesis formulas is found to be better than 0.75% for 9256 CPWs samples. © 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2008. 相似文献
105.
The continuous production of hydrogen from cyclohexanes is achieved effectively using Pt/ACF (ACF = activated carbon fiber) catalysts in a fixed-bed flow reactor. The Pt catalysts are more effective than a Pd/ACF catalyst for the reaction. Besides cyclohexane, methylcyclohexane, 1,4-dimethylcyclohexane, and p-menthane can also be employed as hydrogen source in the reaction system. 相似文献
106.
This work is concerned with the efficient design of a reverse logistics network using an extended version of models currently found in the literature. Those traditional, basic models are formulated as mixed integer linear programs (MILP-model) and determine which facilities to open that minimize the investment, processing, transportation, disposal and penalty costs while supply, demand and capacity constraints are satisfied. However, we show that they can be improved when they are combined with a queueing model because it enables to account for (1) some dynamic aspects like lead time and inventory positions, and (2) the higher degree of uncertainty inherent to reverse logistics. Since this extension introduces nonlinear relationships, the problem is defined as a mixed integer nonlinear program (MINLP-model). Due to this additional complexity, the MINLP-model is presented for a single product-single-level network. Several examples are solved with a genetic algorithm based on the technique of differential evolution. 相似文献
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109.
南桐矿区龙潭煤系热演化及煤变质研究 总被引:2,自引:0,他引:2
川东地区二叠系龙潭煤系煤变质分带与褶皱关系密切,背斜部位变质浅,向斜部位变质深,且变化急剧.在对南桐矿区重点研究的基础上,用沉积速率比值法和沉积趋势法恢复了川东地区各时期的沉积厚度以及褶皱运动前后龙潭煤系的热演化史,并用Hood法确定了煤变质阶段,对川东的煤变质规律作出了合理的解释。 相似文献
110.
将Willenborg的超载残余应力场模型与裂尖形变动力学、裂尖表面析氢反应电化学动力学以及裂尖材料内部氢的扩散动力学和热力学相结合,建立了氢脆腐蚀疲劳裂纹扩展(CFCG)超载效应的定量描述模型,给出了超载对裂尖表面析氢电化学反应及裂尖氢扩展影响的一系列判据和表达式.用上述模型进行的预测表明,对于超高强度钢,当两次超载周次之间裂纹扩展长度ad远小于超载塑性区尺寸rpOL与恒载塑性区尺寸rpCLA之差,即ad<<rpOL-rpCLA时,CFCG会发生比空气疲劳还强烈的超载迟滞效应.而当ad>rpOL-rpCLA时,可能会发生超载加速效应.这种预测在后文中由试验的宏观规律与断口特征得到充分验证. 相似文献