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1.
区域经济的发展受许多不同因素的影响,本结合西藏社会经济发展的特点,选取了总产值指标、第一产业指标、第二产业指标和第三产业指标等四大类指标体系,采用灰色关联分析法对西藏的区域经济系统进行了简要的分析评价,以研究西藏区域经济的发展状况,从社会经济的角度探讨西藏经济发展落后的原因,以期能为西藏经济发展政策提供参考依据。 相似文献
2.
网络股泡沫大小测度研究 总被引:1,自引:0,他引:1
网络股泡沫是最能反映网络泡沫本质的表现形式,本文利用理性预期理论,构建了网络股泡沫大小的测度模型,说明网络股泡沫的存在,在此基础上确定了网络股泡沫大小的测度指标,并以雅虎公司股票为例对泡沫的大小进行了测度,结果符合网络泡沫的实际情况。 相似文献
3.
This study analyzes the economics of transshipping biomass from truck to train in a North American setting. Transshipment
will only be economic when the cost per unit distance of a second transportation mode is less than the original mode. There
is an optimum number of transshipment terminals which is related to biomass yield. Transshipment incurs incremental fixed
costs, and hence there is a minimum shipping distance for rail transport above which lower costs/km offset the incremental
fixed costs. For transport by dedicated unit train with an optimum number of terminals, the minimum economic rail shipping
distance for straw is 170 km, and for boreal forest harvest residue wood chips is 145 km. The minimum economic shipping distance
for straw exceeds the biomass draw distance for economically sized centrally located power plants, and hence the prospects
for rail transport are limited to cases in which traffic congestion from truck transport would otherwise preclude project
development. Ideally, wood chip transport costs would be lowered by rail transshipment for an economically sized centrally
located power plant, but in a specific case in Alberta, Canada, the layout of existing rail lines precludes a centrally located
plant supplied by rail, whereas a more versatile road system enables it by truck. Hence for wood chips as well as straw the
economic incentive for rail transport to centrally located processing plants is limited. Rail transshipment may still be preferred
in cases in which road congestion precludes truck delivery, for example as result of community objections. 相似文献
4.
5.
Two studies investigated how decision makers characterize alternatives in important real-life decisions, which they themselves had made (to leave a partner, to choose an education and to choose a home). First, the participants indicated a very high degree of involvement in the decisions studied and about half of the participants gave maximum involvement ratings for the partner decision. Second, the results showed that concepts that are essential in most decision theories, such as, consequence, probability and value were important characteristics of the decisions. Third, emotion, positive and negative affect were also important characteristics. Fourth, value and emotion were uncorrelated. Fifth, the patterns of characteristics of decisions made in the past did not differ markedly from the characteristics given to future decisions. Principal component analyses were performed on the ratings of applicability of the different characteristics across participants for each decision situation. Three factors were extracted. There was one factor for positive affect/emotions and another factor for negative affect/emotions verified in oblique solutions. Thus, different scales are needed to represent emotion/affect components (and not bipolar scales) in real-life important decisions. The third factor represented the way in which a decision was represented (moving pictures dialogue etc.). An analysis restricted to the participants who rated 100% involvement showed an additional fourth factor with “what others would think”, “similar situations”, “values” and “money” as the most prominent characteristics. This points to the importance of controlling for participant involvement in studies of human decision making to enable generalizations to real-life decisions. 相似文献
6.
在有限执行假设下对最优契约的扩展模型研究 总被引:1,自引:0,他引:1
本文运用违约保证金条款改进了代理人事前报酬契约;在契约有限执行的假设下,扩展了代理人的逆向选择模型,并运用扩展逆向选择模型分析了改进后的最优报酬契约。文章指出,改进后的最优报酬契约严格优于委托人为防范代理人违约而被迫采用的非负参与性约束条件下的最优报酬契约。 相似文献
7.
A new collectively fixed point theorem for a family of set-valued mappings defined on product spaces of non-compact topological spaces without linear structure is proved and some special cases are also discussed. As applications, some non-empty intersection theorems of sets with convex sections and equilibrium existence theorem of abstract economies are obtained under much weaker assumptions. Our results includes a number of known results as many special cases. 相似文献
8.
投资理论告诉人们,应尽量使投资分散化.但许多投资在实际投资中却常常违背这一原则.本从一个调面分析在一个等均值和有一个无风险资产的均方世界里,交易成本的存在,会使投资产生很强的违背分散化原则的动机。 相似文献
9.
刘松影 《广东微量元素科学》1998,5(5):48-51
对35名铅作业工城套的行为功能测验,接触组与对照组比较,16项行为功能测验中有14项得分有统计学意义(P〈0.01或P〈0.05),半数项目行为功能测验得分有随着铅作业工人龄增长而呈该增或该减的趋势。作者认为铅对作业工人行为功能的影响是肯定的,用行为功能测验的方法来研究铅的神经毒性是可取的简便方法。 相似文献
10.
W. Suckow 《Isotopes in environmental and health studies》2013,49(12):447-455
Wesentliche Bedeutung für die Strahlenausnutzung in γ-Bestrahlungsanlagen mit Reaktorbrennelementen hat die Quellenform, wobei der besonderen Quelldichteverteilung Rechnung zu tragen ist. Es wurden Bewertungskenngröβen abgeleitet, mit deren Hilfe Optimalvarianten der Quellenform für verschiedene Bestrahlgutbedingungen bestimmt werden können. Für fünf Quellen-grundformen sind Formeln zur Berechnung der Strahlenfelder angegeben. Mit Hilfe der ermittelten Kenngröβen wurden die verschiedensten Quellenformen verglichen. Die hieraus abgeleiteten Optimalbedingungen sind abschlieβend zusammengefaβt. 相似文献