铁矿石需求分析预测能力多模型比较研究——面板模型与灰色模型、协整模型、ARIMA模型

建立适用于中国和俄罗斯等人均铁矿石需求增长型国家的面板模型,利用面板模型对中国人均铁矿石消费量进行扩张预测,并按不同年份、不同建模期与灰色模型、协整模型、ARIMA模型的样本内、样本外平均扩张预测结果进行对比,说明面板模型的预测精度优于其他三个模型。面板模型与协整模型均能有效地分析因变量与各影响因素间的关系,一般的灰色模型和ARIMA模型无法达到这一目的。考虑模型对变量之间相关关系的刻画能力及预测精度两方面因素,认为四类模型分析铁矿石需求问题的能力排序为:面板模型协整模型灰色模型ARIMA模型,这一结果表明面板模型用于铁矿石需求分析具有优越性。     

三维模型检索算法综述

三维模型检索算法种类繁多,基于内容的三维模型检索算法是目前研究的主要领域。基于内容的检索方法首先计算三维模型数据库中的所有模型和待检索模型的特征描述符,然后通过比较待检索模型与数据库中所有模型的特征描述符的相似度,获取与待检索模型最相似的模型,实现对三维模型的检索：     

浅谈模型方法运用

文章从模型方法的概念,模型的分类和模型的建立等多方面阐明模型方法的特点,从模型方法能起到的作用方面阐述模型方法是科学的分析方法,充分运用模型方法需要了解模型的建立和掌握模型方法的特点,以及运用中需注意的问题.     

省时省力的模型替代法

模型替代法就是为达到一定的目的,用与真实原型相似的模型替代。模型替代法的核心是模型。通俗地讲,模型就是抽取原型的部分属性或功能的模仿体,是对客观事物原型的抽象。模型可以是实体或替代物等物理模型,也可以是抽象的图表模型、数学模型或用计算机软件表达的虚拟模型。     

摩尔库仑模型与CYsoil模型的计算比较

摩尔库仑模型是数据模拟当中的基本模型之一,而cysoil模型作为摩尔库仑模型的衍生模型,有着它独特的优点。为了能够更加明确两模型的部分区别,本文采用FLAC3D软件,针对其他参数均相同的同一基坑采用摩尔库仑模型及cysoil模型分别进行计算。计算不同模型下的基坑周边土体的沉降,进而进行对比,得出结论:M-C模型计算出的水平变形范围要比C-Y模型的要大,C-Y模型的变形范围更为集中一些。     

品牌形象典型模型比较性研究

论述了品牌形象的定义及四个品牌形象典型模型,即Krimani模型、凯勒模型、克里斯南模型、贝尔模型。通过对这些模型的分析,本文比较了各模型中品牌形象的构成要素及其差异,并在此基础上总结出贝尔模型是目前品牌形象量化研究运用最多的模型之一的原因所在。     

基于BP神经网络的两参数区域对流层延迟模型

为了提高区域对流层延迟模型的精度,利用BP神经算法构建两参数区域对流层延迟新模型。基于河南省部分CORS基准站的数据,将穿刺面作为研究面,基于BP神经网络模型、平面拟合模型、二次曲面拟合模型分别建立两参数区域对流层延迟模型,并设计了3种不同的建模方案,以验证模型的精度。实验结果表明,BP神经网络模型的对流层延迟精度达到mm级,明显优于其他2种模型,BP神经网络模型和平面拟合模型不仅适用于区域内,同样适用于区域外,证实了新模型的有效性。     

人力资源优化配置模型研究现状及发展趋势

描述了几种人力资源优化配置模型,包括线性规划指派模型、线形回归模型、多目标规划模型、人员流动优化模型、基于CMMI的人力资源配置模型以及基于贝叶斯理论的人力资源配置模型等,并在此基础上就人力资源优化配置模型今后的发展趋势进行了展望。     

信息检索中的代数模型分析

文章主要讨论了信息检索中的代数模型,包括经典向量模型、扩展的向量模型及神经网络模型。通过对三种模型的详细分析得出三种模型各自的特点。     

大伙房水库生态水质动力学模型研究

基于营养盐-浮游植物-碎屑（NPD）结构的生态系统模型,结合表征水体中有机物质浓度的生物化学碳化氧需求（CBOD）变化过程和溶解氧（DO）变化过程,建立了二维生态水质动力学模型。该模型包括了两个子模型,即水动力学子模型和生态系统动力学子模型。生态水质动力学模型的主体部分为有源项的对流扩散方程,生态系统动力学子模型即为该对流扩散方程的生态源项,为了求解生态水质动力学模型中的水动力因素,该模型耦合了二维水动力学子模型,应用有限差分法进行同步求解。     

How Electronic Publishers are Protecting Against Piracy: Doubts About Technical Systems of Protection

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.     

中德海洋学核心期刊论文国际合著的比较分析

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。     

Exploring Multiplexity: Social Network Structures in a Computer-Supported Distance Learning Class

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.     

Our Own Devices: Heterotopic Communication, Discourse, and Culture in the Information Society 1

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.     

Internetworking and the Politics of Science: NSFNET in Internet History

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.     

中国城镇化进程中产业、空间、人口对能源消费的影响分解

在文献回顾的基础上构建城镇化进程中产业、空间与人口的交互发展对能源消费的融合传导机制, 并基于向量形式的Kaya拓展模型与“多项连乘和加总”的LMDI改进形式,对中国1998—2015年间的能耗总量变化进行因素分解。研究显示：城镇化对生产端能耗的拉动效应远大于生活端;传统能源驱动型产业的转型升级 与技术进步缓解了能源压力;近些年除消费支出以外的其他经济单元,因粗放型“三高”发展模式的改善,较居民 消费具有能耗比较优势;居民消费效应仍是间接能耗提升的主导因素,城乡居民消费行为趋同对生活能耗波动的正向贡献日趋增强,并随着人口规模的扩张成为能源可持续发展的掣肘;摊大饼式空间低密度蔓延加剧了能源 消费,仅人口集聚的规模效应对生活能耗波动具有负向贡献。进一步指出在新型城镇化能源约束强化的情境下,虽然产业层面的结构调整与技术进步对能耗的削减效应仍存在,但更应关注人口层面的居民消费方式及用能习 惯的改良,释放空间层面的资源配置对降低能耗的新动能,努力实现共享经济以缓解能耗压力,并据此提出几点 建议。     

New dimensions in vaccinology: A new insight

The development of vaccines to prevent infectious diseases has been one of the most important contributions of biomedical sciences. Increasing understanding in biochemistry, molecular biology, molecular genetics and related fields have provided an opportunity for the development of new generation vaccines that are based on rational design approaches. This is possible because of proper understanding of the microbial-genetics, biochemistry, host-pathogen interaction and recent developments in molecular immunology. Another important improvement made in the quality of vaccine production is the incorporation of immunomodulators or adjuvants with modified delivery vehicles viz liposomes, Iscoms and microspheres apart from alum being used as a gold standard. This article reviews the art of vaccination from Jenner period to present day context highlighting all the developments made at each stage of the vaccine development. Various criteria have been discussed regarding the selection of epitopes that expand B & T cells, its linkage with other accessory cells of the immune system, means to overcome MHC linked immune unresponsiveness, enhanced antigen processing and presentations that specially induce either helper or cytotoxic or mucosal immune responses were critically discussed.     

Online diaries: Reflections on trust,privacy, and exhibitionism

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.     

军队信息化的动因、任务及对策探讨

基于未来高技术战争需求的牵引、军用信息技术发展的推动和构建核心能力的内在要求,我军必须加快信息化建设。为此,本文运用战略管理中的价值链方法对军队的任务及军队信息化的任务进行了全面分析,并提出了加速我军信息化建设的对策。     

The Role of Intermediating Institutions in the Diffusion of Electronic Data Interchange (EDI): How Industry Associations Intervened in Denmark, Finland, and Hong Kong

Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies.