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1.
无尺度偏差的非负权重最优无偏组合预测模型   总被引:1,自引:2,他引:1  
曾勇  唐小我 《预测》1996,15(1):61-63
  相似文献   

2.
递归方差倒数组合预测方法及其应用研究   总被引:1,自引:0,他引:1  
唐小我  傅庚 《预测》1994,13(5):42-47
本文针对简单平均组合预测方法(EW法)的局限性,在递归等权组合预测方法(REW法)[1]的思路基础上,进一步提出了递归方差倒数组合预测方法(RecursivevarianceRecipraslWeighting),即RVRW法,给出了有关的迭代计算公式,实例表明RVRW法在预测精度和收敛速度等方面较REW法具有更大的优越性。同时,该方法完全适用于组合证券投资风险最小化问题。  相似文献   

3.
谭思明 《情报杂志》2006,25(4):23-25,28
就专利组合分析的背帚、概念和目标进行简要地介绍,并对专利组合分析的专利指标、专利组合、专利与市场一体化组合分析的方法以及一体化组合在化工行业的实证研究进行了分析和阐述。由此证明,专利信息是企业战略知识管理系统的一个核心要素,专利组合分析是一个将技术与市场战略紧密结合进行战略决策的非常有价值的工具。  相似文献   

4.
IT项目组合管理是项目管理和决策支持系统中研究的热点问题.对IT项目组合管理理论的形成进行分析,并从项目组合收益、战略对应、风险、成本以及关联性等方面的研究进展进行综述研究,最后总结IT项目组合管理的未来研究方向.  相似文献   

5.
线性规划在确定组合预测组合权数中的应用   总被引:3,自引:0,他引:3  
周传世 《预测》1993,12(4):39-39,41
1 引言在预测的实践中,我们可以利用多种预测模型进行预测。预测模型不同,预测的结果也不相同。为了综合系统地利用各模型的信息,我们采用组合预测模型。组合预测的关键是确定加权系数。本文将以两个合理的度量为目标函数,通过解线性规划问题确定最优的权组合系数。 2 权系数的确定设对于同一预测  相似文献   

6.
变权重组合预测模型的研究   总被引:24,自引:0,他引:24  
周传世  刘永清 《预测》1995,14(4):47-48,57
变权重组合预测模型的研究周传世,刘永清(广东商学院)(华南理工大学)1引言组合预测的研究是现在预测方法领域中研究得最为活跃的一个领域之一,但在变权重组合预测方面的研究还没有多大的进展。变权重组合预测模型的建立与应用是提高预测模型的拟合精度和预测精度、...  相似文献   

7.
徐晓辉 《内江科技》2013,(6):102+66
本文对4P、4C、4R、4S营销组合的分析,结合创新思维的观点,对四种营销组合的因素进行了重新组合,形成了多种组合方式,增加了企业营销方式,使企业营销活动更趋于灵活,有利于提高营销活动的针对性,增强营销效果。  相似文献   

8.
变权组合预测模型研究   总被引:6,自引:0,他引:6  
唐小我  曹长修 《预测》1993,12(3):46-48,62
文献[1]就变权组合预测模型进行了有益的探讨,本文继续研究这一问题,给出完整的计算方法和应用实例。  相似文献   

9.
非线性规划在确定组合预测权系数中的应用   总被引:11,自引:0,他引:11  
王明涛 《预测》1994,13(3):60-61
非线性规划在确定组合预测权系数中的应用王明涛(郑州工学院管理系450002)1引言组合预测是目前预测科学研究的热门课题之一,。组合预测方法的关键是确定组合权系数,唐小我“组合预测计算方去研究”一文[1],给出了求解最优仅系数的公式(后称唐法),但在实...  相似文献   

10.
11.
The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means.  相似文献   

12.
This paper examines the category of "Woman" within the metastructure of a system of knowledge organization. We trace the subject scheme used to list books about women in a standard bibliographic guide over the first three-quarters of the twentieth century.Building on the feminist critique of subject representation, our analysis documents how the category was continually constructed over time, providing evidence of multiplication, isolation, and confusion in the process. The outcome is a framework that fails to capture the complex nature of knowledge about women and conceals relationships to the larger body of knowledge. The case of this legacy system exemplifies problems associated with representing the complexity and integration of knowledge and provides a basis for considering the potential residual impacts of current information organization and navigation systems.  相似文献   

13.
The main premise of this article is that in information societies generally, and in virtual social contexts particularly, a distinctive style of interaction to facilitate the communication of difference, heterotopic communication , has emerged. It rests on two cultural foundations: an ideological belief in the positive, socially integrating power of communication, and a prevailing ethic of instrumental rationality, subjective individualism, and strategically practiced self-interest. The former is demonstrated by the use of simulation and spectacle as sources of information; exhibitionism/voyeurism as a communicative style; and the awareness of surveillance. The latter is seen in the competitive use of knowledge as a commodity; a surface globalism masking deep parochialism; lateral as well as vertical information inequity; and the use of public versus private as strategies for engagement rather than as spaces. Those who engage in heterotopic communication resort to their 'own devices' both in the sense of personal agendas, strategies, interests, and interpretations, and in the form of the telecommunication tools that help realize them. These personal and technological devices allow individuals with the right educational and technical resources to avoid exposure to disagreement, difference, or other information that does not serve their direct purposes or reflect their particular views of the world; yet they also help convey the appearance of openness, availability, and cooperation. This style of interaction is used strategically in combination with information and communication technologies to gain social or economic advantages, but it may encourage social separatism and parochialism, inhibit the negotiation of disputes, and emphasize competing interests.  相似文献   

14.
This article presents an account of the process of development of the NSFNET and its significance for the emergence of the Internet of the 1990s. The fact that the development of the interconnected system of computer networks occurred within the realm of academic research is not incidental. The dynamics of the world of scientific research were intimately related to the shaping of the network and to the way in which it spread to other sectors of society. The construction of computer networks crossed the boundaries between science and society in order to build the scientific realm by transforming the world in which it is embedded.  相似文献   

15.
结合元极学三元学说,剖析《管子》的基本概念如道、宙合、精、德、中、智等的内涵,揭示时间、空间、精等是天地万物的共同特征或本质,注重时、空、精的层次性、无限性,以及人的生命本和本性展发。  相似文献   

16.
Contrary to the "retro" image often awarded them, and despite their continuing enthusiasm and responsibility for the organization of printed materials, librarians are upbeat about the prospects of an information society driven primarily by electronic technologies, but in which libraries can play an important part. Public librarians detect a natural correlation between the historic democratic mission of their institution and the increased accessibility made possible by digitalized sources. The library community's acceptance of the information society idea as a "given" social phenomenon supports discourses that play down historical continuities and herald the dawn of a new age. Such discourses ignore or reject historical evidence that points to the existence of past information societies, revolutions, and infrastructures defined, in part, by the operation of indirect surveillance, constituted by the bureaucratic information systems of modernity. Victorian Britain serves as a good example of an early information society, to which public libraries, themselves micro-information societies, contributed significantly. The role played by public librarians in the Victorian information society, illustrated in this article by evidence drawn from the contemporary library press, is seen in their preoccupation with the surveillance and ordering of knowledge; their adoption for library operations of the businesslike, bureaucratic procedures described recently by business historians; and their panoptic tracking of users and their activities.  相似文献   

17.
中德海洋学核心期刊论文国际合著的比较分析   总被引:1,自引:0,他引:1  
万琪  华薇娜 《现代情报》2016,36(2):150-156
本研究选取Web of Science数据库,收集中国和德国发表的海洋学论文,将论文分为国际合著组与非国际合著组,利用文献计量学的方法,借助EXCEL、SPSS和UCINET软件,比较两国各年的发文量、论文的篇均作者和篇均参考文献数、收录期刊的影响因子、论文的被引频次以及合著国家。研究结果显示,中国海洋学领域的国际合著起步晚于德国,但发展迅速,近年来中国海洋学国际合著的论文量已超过德国;同时中国海洋学国际合著论文的质量和学术影响力都弱于德国,并且中国海洋学论文合著国家的范围也小于德国海洋学的合著国家。  相似文献   

18.
Trust between transaction partners in cyberspace has come to be considered a distinct possibility. In this article the focus is on the conditions for its creation by way of assuming, not inferring trust. After a survey of its development over the years (in the writings of authors like Luhmann, Baier, Gambetta, and Pettit), this mechanism of trust is explored in a study of personal journal blogs. After a brief presentation of some technicalities of blogging and authors’ motives for writing their diaries, I try to answer the question, ‘Why do the overwhelming majority of web diarists dare to expose the intimate details of their lives to the world at large?’ It is argued that the mechanism of assuming trust is at play: authors simply assume that future visitors to their blog will be sympathetic readers, worthy of their intimacies. This assumption then may create a self-fulfilling cycle of mutual admiration. Thereupon, this phenomenon of blogging about one’s intimacies is linked to Calvert’s theory of ‘mediated voyeurism’ and Mathiesen’s notion of ‘synopticism’. It is to be interpreted as a form of ‘empowering exhibitionism’ that reaffirms subjectivity. Various types of ‘synopticon’ are distinguished, each drawing the line between public and private differently. In the most ‘radical’ synopticon blogging proceeds in total transparency and the concept of privacy is declared obsolete; the societal gaze of surveillance is proudly returned and nullified. Finally it is shown that, in practice, these conceptions of blogging are put to a severe test, while authors often have to cope with known people from ‘real life’ complaining, and with ‘trolling’ strangers.  相似文献   

19.
A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction.  相似文献   

20.
The Principles of Fair Information Practice are almost three decades old and need to be broadened to take account of new technologies for collecting personal information such as drug testing, video cameras, electronic location monitoring, and the Internet. I argue that the ethics of a surveillance activity must be judged according to the means, the context and conditions of data collection, and the uses/goals, and suggest 29 questions related to this. The more one can answer these questions in a way that affirms the underlying principle (or a condition supportive of it), the more ethical the use of a tactic is likely to be. Four conditions are identified that, when breached, are likely to violate an individual's reasonable expectation of privacy. Respect for the dignity of the person is a central factor and emphasis is put on the avoidance of harm, validity, trust, notice, and permission when crossing personal borders.  相似文献   

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