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21.
周德华 《重庆科技学院学报(自然科学版)》2003,5(2):23-25
将灰色系统理论应用于股市预测 ,建立了灾变日期预测模型。运用该模型进行上涨周、局部低点周及灾变转折点预测的实例表明 ,灾变预测模型在股市预测中具有操作性强、实用价值高、易于普及应用的特点。 相似文献
22.
本文以国际高档服装品牌A进入上海市场为例进行典型分析,具体分析国际服装品牌A在进入上海 男装市场的市场营销策略,也希望对其它的服装品牌进入上海市场时能够有所帮助。 相似文献
23.
本文分析了铁路施工企业工程造价动态分析管理系统,介绍了系统设计思想和技术要点及开发过程中的体会. 相似文献
24.
吕维山 《石油化工高等学校学报》1997,10(2):74-78
技术商品是一种特殊商品 ,它与一般商品相比有着许多特殊性。从技术商品的概念入手 ,分析了技术商品的特征 ,并将其按照技术的研究对象和应用效果及技术所应用的行业不同进行了分类。阐述了技术商品的价值和使用价值 ,论述了技术商品的价格形成。利用Cobb -Douglas生产函数 ,构造出了技术商品的价格模型。说明技术商品的价格决定于技术商品的影子价值和其消费风险 相似文献
25.
《国际互联网参考资料服务季刊》2013,18(1):107-120
Abstract This paper describes the details of maintaining an Internet information service, focusing on the experience of Documents Center staff in the University of Michigan Library with the “Department of Commerce Economic Data (UMich)” gopher area. Described are the evolution of the service, the logistics of obtaining and posting the files, developing staff skills and knowledge, file selection, and provision of enhanced access and assistance. Long term considerations are discussed. Internet information services differ from more traditional library services and materials maintenance because they require special skills, equipment, and constant reassessment. Despite this, the benefits of providing such services are significant for the academic library's clientele, its staff, and the Internet community overall. 相似文献
26.
This paper examines the effect of credit constraints on the sale price expectations of homeowners. We extend the results of Genesove and Mayer (1997) by using a sample of mover and non-mover families living in the Netherlands—a country without formal down-payment requirements. We find that homeowners who are more credit constrained expect to sell their house for a higher price. Homeowners already seem to compensate for credit constraints at the very first stages of the transaction process. These results imply that the findings of Genesove and Mayer (1997) are much more generally applicable than previously considered. 相似文献
27.
《Energy Policy》2014
This paper explores the degree of competition in various gasoline markets and infers possible causes of price asymmetry across the globe. For this purpose we use the Dynamic Ordinary Least Square method in order to estimate price asymmetry in twelve European countries and the United States for a sample of weekly observations which spans the period from June 1996 to August 2011. The results indicate the common perception that less competitive gasoline markets exhibit price asymmetry, while highly competitive gasoline markets follow a symmetric price adjustment path. Finally, the inclusion of taxes (VAT and excise tax) into retail gasoline prices, supports the existence of price asymmetry in many European countries. 相似文献
28.
Generation bidding strategy in a pool based electricity market using Shuffled Frog Leaping Algorithm
In an electricity market generation companies need suitable bidding models to maximize their profits. Therefore, each supplier will bid strategically for choosing the bidding coefficients to counter the competitors bidding strategy. In this paper optimal bidding strategy problem is solved using a novel algorithm based on Shuffled Frog Leaping Algorithm (SFLA). It is memetic meta-heuristic that is designed to seek a global optimal solution by performing a heuristic search. It combines the benefits of the Genetic-based Memetic Algorithm (MA) and the social behavior-based Particle Swarm Optimization (PSO). Due to this it has better precise search which avoids premature convergence and selection of operators. Therefore, the proposed method overcomes the short comings of selection of operators and premature convergence of Genetic Algorithm (GA) and PSO method. Important merit of the proposed SFALA is that faster convergence. The proposed method is numerically verified through computer simulations on IEEE 30-bus system consist of 6 suppliers and practical 75-bus Indian system consist of 15 suppliers. The result shows that SFLA takes less computational time and producing higher profits compared to Fuzzy Adaptive PSO (FAPSO), PSO and GA. 相似文献
29.
The world market for functional foods has grown dynamically and China is expected to be one of the most promising markets. But little is understood the formation mechanisms of consumers’ purchase attitude and intention toward functional foods in Mainland China. The current study investigates the roles of trust, health consciousness and price in shaping consumers’ purchase intention toward functional foods by focusing on purchase attitude as a mediator and food neophobia as a moderator. Results from the sample of 1144 Chinese suggest that Chinese consumers had moderate purchase intention toward functional foods. Trust in the food system and health consciousness positively affects purchase intention via purchase attitude. Price negatively affects purchase intention; meanwhile, the negative effect could be counteracted by health consciousness. Food neophobia does not directly affect individuals’ purchase attitude or intention, but moderates the relationships between antecedents and them. Consumers with a low level of food neophobia treat higher price as a monetary sacrifice, while their counterparts may regard a higher price as a greater quality signal. The study offers the food industry insights into the development and marketing of functional foods targeted to the Mainland China market. 相似文献
30.
Since 2010 the Dutch photovoltaic (PV) market has been growing fast, with around doubling of installed capacity in 2011 and 2012. Four quarterly inventories have been made in 2012 for modules, inverters, and systems that are presently available for purchase in the Netherlands. We have found that the average selling price of modules, inverters, and systems decreased with 44.3, 14, and 7.3–10.2%, respectively: average selling prices are 1.26 €/Wp, 0.41 €/Wp, and 1.46 €/Wp for modules, inverters, and systems on tilted roofs, respectively, at the end of 2012. Average installation costs amount to 0.43 €/Wp. Using an energy yield of 900 kWh/kWp, 25 years system lifetime, 6% discount rate, and 1% operation and maintenance (O&M) cost, a levelized cost of electricity (LCOE) is calculated for a 2.5 kWp system to be 0.194 €/kWh for a system price of 1.98 €/Wp (including installation). Grid parity conditions are apparent, with electricity retail prices of around 0.23 €/kWh. 相似文献