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1.
Product life cycle (PLC) prediction plays a crucial role in strategic planning and policy definition for high-technology products. Forecast methodologies which can predict PLCs accurately can help to achieve successful strategic decision-making, forecasting, and foresight activities in high-technology firms, research institutes, governments, and universities. Over the past few decades, even though analytic framework strategies have been proposed for production, marketing, R&D (research and development), and finance, aiming at each stage of PLCs, forecast methodologies with which to predict PLCs are few. The purpose of this research is to develop a novel forecast methodology to allow for predictions of product life time (PLT) and the annual shipment of products during the entire PLC of multiple generation products. A novel two-stage fuzzy piecewise regression analysis method is proposed in this paper. In the first stage, the product life-time of the specific generation to be analyzed will be predicted by the fuzzy piecewise regression line that is derived based upon the product life-time of earlier generations. In the second stage of the forecast methodology, the annual shipment of products of the specified generation will be predicted by deriving annual fuzzy regression lines for each generation, based upon the historical data on the earlier generations' products. An empirical study predicting the life-time and the annual shipment of the 16 Mb (Mega bit) DRAM (Dynamic Random Access Memory) PLC is illustrated to validate the analytical process. The results demonstrate that two-stage fuzzy piecewise regression analysis can predict multiple generation PLT and PLC precisely, thereby serving as a foundation for future strategic planning, policy definitions and foresights.  相似文献   
2.
国际航空物流中心日益成为区域经济发展、国家对外开放和国际贸易往来的强劲动力和重要功能承载区。对国内外国际航空物流中心发展现状和成功经验进行分析和总结,结合相关文献和专家咨询,对国际航空物流中心发展的影响因素和指标体系进行了归纳,并运用ISM解释结构模型最终得到了这些影响因素指标的层级结构。自下而上分别为深层影响因素层、产业支撑和基础配套体系层、软硬件基础设施层、业务服务层、运营成本控制层和空中通道建设层。下一层级的因素对上一层级的因素有影响和驱动作用。通过因素分析,理清了国际航空物流中心发展的关键因素和因素间的关联关系,为更好推动国际航空物流中心的发展提供理论指导。  相似文献   
3.
以浙江电网企业转型现代能源综合服务的具体战略与发展规划为研究背景,针对能源综合服务系统的运行规划目标,开展基于运行规划的能源综合服务系统能效管理研究。从系统工程的视角出发,以能源流为纽带,基于多尺度能源系统建模方法,构建了能源综合服务系统模型,并结合系统综合能效,采用粒子群优化算法来优化系统各设备单元的运行策略,以实现基于运行规划的最优能效管理。通过能源综合服务系统模型计算表明,大规模清洁能源和可再生能源的接入,可以明显提高系统综合能效;随着区域用户总冷量和/或总热量需求占总电力需求的比值增大,系统最优综合能效逐渐增大;与使用内燃机、燃气轮机及汽轮机为原动机的热电联产系统相比,使用燃料电池为原动机的热电联产系统可以使能源综合服务系统综合能效更优。  相似文献   
4.
The bureaucratic tendencies to organize work in Higher Education Institutions (HEIs) of which facilitates personnel control and the mechanical ways to measure educational content are the ones that shatter education in pieces, under the hierarchy criterion, also shattering the professor's labor. This organizational method results in an incompetent education, leaving very negative consequences for teaching development. We address this problem by using systemic modeling and Structural Equations Systems (SEM) to confirm hypotheses from scientific observation. It was proven that there was a negative impact of mechanistic management which affected teacher's development. This was proven in context in two HEIs located in Villahermosa (Tabasco, Mexico).  相似文献   
5.
通过对中原地区民间刺绣的色彩、造型艺术和工艺技法的深入研究,展现了民间刺绣独特的色彩应用理论,夸张多变的造型和工艺上独到的艺术风格,为民间刺绣的现代应用指明方向。  相似文献   
6.
文章对螺旋桨的一般设计过程和基于UG的建模功能,以及对已有的螺旋桨进行逆向建模的整个过程进行了系统介绍。  相似文献   
7.
This paper presents a modeling methodology capable of accounting for spatial correlation across choice alternatives in discrete choice modeling applications. Many location choice (e.g., residential location, workplace location, destination location) modeling contexts involve choice sets where alternatives are spatially correlated with one another due to unobserved factors. In the presence of such spatial correlation, traditional discrete choice modeling methods that are often based on the assumption of independence among choice alternatives are not appropriate. In this paper, a Generalized Spatially Correlated Logit (GSCL) model that allows one to represent the degree of spatial correlation as a function of a multi-dimensional vector of attributes characterizing each pair of location choice alternatives is formulated and presented. The formulation of the GSCL model allows one to accommodate alternative correlation mechanisms rather than pre-imposing restrictive correlation assumptions on the location choice alternatives. The model is applied to the analysis of residential location choice behavior using a sample of households drawn from the 2000 San Francisco Bay Area Travel Survey (BATS) data set. Model estimation results obtained from the GSCL are compared against those obtained using the standard multinomial logit (MNL) model and the spatially correlated logit (SCL) model where only correlations across neighboring (or adjacent) alternatives are accommodated. Model findings suggest that there is significant spatial correlation across alternatives that do not share a common boundary, and that the GSCL offers the ability to more accurately capture spatial location choice behavior.  相似文献   
8.
基于模糊概念的可疑金融交易量化关联规则研究   总被引:3,自引:0,他引:3  
从模糊集的基本理论入手,通过定义模糊概念软化属性域的划分边界,提出了一种新的基于模糊概念的量化关联规则方法.本方法克服了因划分区间而造成数据缺失的不足.最后通过将某市2004年的实际数据运用到建立的算法中,验证算法的有效性,为有效开展可疑金融交易识别提供了有益的参考.  相似文献   
9.
This article aims to evaluate the service quality experienced at academic conferences held at the Universidad Técnica Particular de Loja in Ecuador. Our approach is based on fuzzy logic and ideal solutions to calculate a global attendee satisfaction index for specific market segments: Gender, nationality, and age. Current literature on the service quality experienced by conference attendees is still scarce. Our results show that the analyzed segments experience varying levels of satisfaction, and that the more influential attributes to each of them are also different. Our results can be applied to improve the competitiveness of Loja and that of Universidad Técnica Particular de Loja.  相似文献   
10.
This study proposes a novel approach, the Fuzzy Rasch model, which combines Item Response Theory (IRT) and fuzzy set theory. This paper applies the Fuzzy Rasch model in Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) to analyse the Tourism Destination Competitiveness (TDC) of nine Asian countries: China, Hong Kong, Japan, Korea, Malaysia, Singapore, Taiwan, Thailand and the Philippines. The study was conducted in 2009 using 6 criteria and 15 indices. The results demonstrate the feasibility of applying the Fuzzy Rasch model in TOPSIS to analyse TDC in Asian countries. In addition, the proposed model also provides an effective means of applying the MCDM method to study TDC. Furthermore, in 2009, the Asian countries were ranked from most to least competitive as follows: China, Japan, Hong Kong, Malaysia, Thailand, Singapore, Taiwan, Korea and the Philippines.  相似文献   
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