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1.
采用Norton模型对产品更新换代扩散趋势的研究——以中国互联网用户上网方式的更新换代为例 总被引：2，自引：0，他引：2
本文在Bass模型的基础上,详细介绍了产品更新换代扩散的Norton模型,并例举了通信产业的产品更新换代扩散的实例,中国互联网上网方式的更新换代的发展。模型参数的估算是影响模型准确性的一个重要方面,论文总结了前人的成果,采用遗传算法作为Norton模型的参数估计方法,并对中国互联网的上网方式,如拨号上网、ISDN(综合业务数字网)上网、宽带上网的扩散进行实证研究,模型得出另人满意的结果,并将结果与Bass模型进行了比较和讨论,得出结论,采用Norton模型研究产品更新换代扩散是一种更好的选择。最后,论文对中国移动通信网络发展提出展望。 相似文献
2.
山东蓬莱旅游业发展的资源基础与战略构想 总被引：3，自引：0，他引：3
蓬莱市位于山东半岛北端,是中国古代四大港口和近代四大对外通商口岸之一,其历史悠久,知名度高,独特性强,文化积淀丰厚,高品位资源分布集中,具有丰富的人文旅游资源.本文全面分析了蓬莱旅游资源特征;并基于该市旅游产业发展现状及其在发展中存在的经济基础相对薄弱,产业结构偏低,市政建设欠缺等问题,提出了切实可行的客源分级策略、旅游资源深度开发策略、旅游文化开发策略;同时提出了相应的发展措施,建议把发展旅游业纳入政府工作议程,将旅游业作为蓬莱市经济发展的战略性产业,并在加强旅游环保和环保旅游的同时,实行联合促销,强化旅游宣传,促进旅游业的全面和健康的发展. 相似文献
3.
The inability to touch products is a fundamental shortcoming in online shopping because humans typically use the sense of touch to evaluate the utilitarian product functionality and to obtain hedonic sensory enjoyment, which the instrumental and autotelic need for touch capture. This study of 900 consumers looks at the interplay between need for touch and imagination to study how imagination compensates for the lack of touch when consumers shop in a 360-virtual store. The study finds that while telepresence of a 360-virtual store improves consumer attitudes toward virtual shopping, the need for hedonic sensory enjoyment – autotelic need for touch – significantly reduces this effect. Further, imagination can compensate for the need for touch; yet this finding holds only for the instrumental need for touch, not for the autotelic need for touch. Consequently, we conclude that imagination can compensate for the utilitarian need to touch products in a 360-virtual store. 相似文献
4.
During crises, there is a need for a large amount of information in a short period. Such need creates the base for misinformation to spread within and outside the affected community. This may result in misinformation harms that can generate serious short term or long-term consequences. In such situations, there is a need for a joint human-machine effort to mitigate misinformation. Though there has been research in the area of management of AI in the recent past, there has been scarce work in examining situations where machines and humans interact for mitigating misinformation. In order to systematically analyze misinformation and suggest mechanisms for mitigation, we draw on Activity Theory to conceptualize a suitable framework. Such a framework will enable investigating human-machine interactions through loops of “misinformation generation” and “misinformation mitigation” activities for mitigating misinformation harms. The paper also validates the framework using three different target audiences, undergraduates, graduates and professionals. 相似文献
5.
该文试图对我国幼儿艺术教育的现状和学前儿童艺术教育内容的相关理论进行分析,总结目前我国农村幼儿园艺术教育存在的问题,更准确地认识我国幼儿园艺术教育的实情,为我国幼儿园艺术教育研究提供更新的研究视野。构建科学合理、适合我国国情的学前儿童艺术教育课程体系,为建设更加完善、更有生命力的农村幼儿园艺术教育理论体系提供借鉴。 相似文献
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There is an increasing recognition that various stakeholder groups for e-government have a significant role to play in ensuring the long-term success of the e-government enterprise. This article seeks to contribute to the understanding of the stakeholders’ multiple perspectives by proposing typologies of stakeholder roles, and stakeholder benefits, respectively, and embedding these in a stakeholder benefits analysis tool. A literature review is used to surface the diverse existing categorizations of e-government stakeholders and their interests and the benefits sought. This review informs a proposal for a typology of stakeholder roles, and for a typology of stakeholder benefits, which together are used to construct an initial proposal for a stakeholder benefits analysis tool (SBAT), which can be used to map stakeholder roles to stakeholder benefits. This tool has been tested by an expert group, and revised. This exploratory study is an important first step towards the development of tools and approaches for understanding the benefits sought by a wide range of different stakeholder groups in e-government. Progress in the development of such tools is important for the development of knowledge and practice, policy, and evaluation with respect to stakeholder engagement with, and participation in, e-government. 相似文献
7.
重点开发区域农田生态补偿的农户受偿意愿分析——武汉市的例证 总被引：2，自引：0，他引：2
重点开发区域农户参与农田保护性耕作的机会成本极大,农田生态补偿机制的构建刻不容缓。本文以武汉市为实证,从保护性耕作的视角入手,采用条件价值评估法(CVM)探讨了重点开发区域农田生态补偿农户受偿额度,在此基础上,通过Tobit回归模型检验影响农户受偿意愿的相关因素。研究结果表明:1随着化肥、农药的减少比例从10%增加到50%,农户的受偿额度分别由4 687.50元/(hm2·a)、4 750.05元/(hm2·a)增加到7 720.65元/(hm2·a)、10 227.30元/(hm2·a),且在同等减少比例下,农户对农药减少的受偿额度要大于化肥减少的受偿额度;2性别、距离城镇远近、改善农田生态环境期望指数对农户减少化肥施用受偿意愿有正向显著影响,而年龄和家庭整体劳动能力有负向显著影响。村集体经济状况、改善农田生态环境期望指数对农户减少农药施用受偿意愿有正向显著影响,而家庭年现金收入有负向显著影响。 相似文献
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On the web, a huge variety of text collections contain knowledge in different expertise domains, such as technology or medicine. The texts are written for different uses and thus for people having different levels of expertise on the domain. Texts intended for professionals may not be understandable at all by a lay person, and texts for lay people may not contain all the detailed information needed by a professional. Many information retrieval applications, such as search engines, would offer better user experience if they were able to select the text sources that best fit the expertise level of the user. In this article, we propose a novel approach for assessing the difficulty level of a document: our method assesses difficulty for each user separately. The method enables, for instance, offering information in a personalised manner based on the user’s knowledge of different domains. The method is based on the comparison of terms appearing in a document and terms known by the user. We present two ways to collect information about the terminology the user knows: by directly asking the users the difficulty of terms or, as a novel automatic approach, indirectly by analysing texts written by the users. We examine the applicability of the methodology with text documents in the medical domain. The results show that the method is able to distinguish between documents written for lay people and documents written for experts. 相似文献
9.
2019年底暴发的新冠肺炎疫情是一次重大的公共卫生事件,它对我国乃至世界的社会经济都将产生巨大而深远的影响。遗憾的是,这样的事件已不再是百年一遇,而是十年一遇或更短的时间,因此如何有效地应对大规模传染性疾病的暴发是人类社会面临的十分重要而迫切的问题。这次新冠肺炎疫情既是一个不幸,也是一个难得的学习机会。通过对疫情防控过程的回顾,以及对在该过程中所遇到的一些困难的梳理,发现很多问题最终都可以归结为供需矛盾的问题,而供给侧的挑战通常又都源于供应链的无序和混乱。文章结合现代供应链管理理论的一些基本原理,对疫情防控工作进行了分析并给出了建议,如建立全国联网传染病监测中心、国家防控战略物资安全库存、国家突发事件应急管理指挥中心等。另外,疫后经济重建也至关重要,因此还从供应链思维的角度,分析了新冠肺炎疫情的行业影响,以及企业复工复产过程中应该注意的事项。 相似文献
10.
Generating gene summaries from biomedical literature: A study of semi-structured summarization 总被引：3，自引：0，他引：3
Xu Ling Jing Jiang Xin He Qiaozhu Mei Chengxiang Zhai Bruce Schatz 《Information processing & management》2007,43(6):1777
Most knowledge accumulated through scientific discoveries in genomics and related biomedical disciplines is buried in the vast amount of biomedical literature. Since understanding gene regulations is fundamental to biomedical research, summarizing all the existing knowledge about a gene based on literature is highly desirable to help biologists digest the literature. In this paper, we present a study of methods for automatically generating gene summaries from biomedical literature. Unlike most existing work on automatic text summarization, in which the generated summary is often a list of extracted sentences, we propose to generate a semi-structured summary which consists of sentences covering specific semantic aspects of a gene. Such a semi-structured summary is more appropriate for describing genes and poses special challenges for automatic text summarization. We propose a two-stage approach to generate such a summary for a given gene – first retrieving articles about a gene and then extracting sentences for each specified semantic aspect. We address the issue of gene name variation in the first stage and propose several different methods for sentence extraction in the second stage. We evaluate the proposed methods using a test set with 20 genes. Experiment results show that the proposed methods can generate useful semi-structured gene summaries automatically from biomedical literature, and our proposed methods outperform general purpose summarization methods. Among all the proposed methods for sentence extraction, a probabilistic language modeling approach that models gene context performs the best. 相似文献
11.
促进员工创造力成为当代领导面临的主要挑战和目标。本研究整合社会认知理论、社会信息处理理论、创造力成分模型等理论视角,构建了自我牺牲型领导影响员工创造力的理论模型,以78个研发团队(78个团队主管,314个团队成员)为样本,对研究假设及影响路径进行了实证检验,试图揭示2者关系中的关键中介机制和调节机制。研究结果表明:(1)自我牺牲型领导对创造力自我效能感、员工创造力具有显著的跨层次正向预测效果,且对创造力支持氛围具有正向预测效果;(2)创造力支持氛围与创造力自我效能感在自我牺牲型领导与员工创造力关系之间起到跨层次中介作用;(3)创造力支持氛围对创造力自我效能感与员工创造力之间的关系具有显著的跨层次调节效应,创造力支持氛围越高,2者之间的正向关系越强。 相似文献
12.
Current Web-based search engines presume a category search for a specific group of users. This approach is appropriate for generalized information searches since it is based on statistically generated user profiles. However, in some applications, such as medicine and law, an individualized search for a specific user at a given point in time is desired. In addition, the use of specialized terminology in some fields necessitates guidance for the non-expert to be successful in locating the desired information. This paper presents a new decision support system enabled by the analytic hierarchy process and intelligent software agents that can be used by researchers and practitioners in technical fields to aid information retrieval and improve search results from a controlled vocabulary. An application from telemedicine is given to illustrate the potential improvements. 相似文献
13.
Five hundred million tweets are posted daily, making Twitter a major social media platform from which topical information on events can be extracted. These events are represented by three main dimensions: time, location and entity-related information. The focus of this paper is location, which is an essential dimension for geo-spatial applications, either when helping rescue operations during a disaster or when used for contextual recommendations. While the first type of application needs high recall, the second is more precision-oriented. This paper studies the recall/precision trade-off, combining different methods to extract locations. In the context of short posts, applying tools that have been developed for natural language is not sufficient given the nature of tweets which are generally too short to be linguistically correct. Also bearing in mind the high number of posts that need to be handled, we hypothesize that predicting whether a post contains a location or not could make the location extractors more focused and thus more effective. We introduce a model to predict whether a tweet contains a location or not and show that location prediction is a useful pre-processing step for location extraction. We define a number of new tweet features and we conduct an intensive evaluation. Our findings are that (1) combining existing location extraction tools is effective for precision-oriented or recall-oriented results, (2) enriching tweet representation is effective for predicting whether a tweet contains a location or not, (3) words appearing in a geography gazetteer and the occurrence of a preposition just before a proper noun are the two most important features for predicting the occurrence of a location in tweets, and (4) the accuracy of location extraction improves when it is possible to predict that there is a location in a tweet. 相似文献
14.
Digital twins, along with the internet of things (IoT), data mining, and machine learning technologies, offer great potential in the transformation of today’s manufacturing paradigm toward intelligent manufacturing. Production control in petrochemical industry involves complex circumstances and a high demand for timeliness; therefore, agile and smart controls are important components of intelligent manufacturing in the petrochemical industry. This paper proposes a framework and approaches for constructing a digital twin based on the petrochemical industrial IoT, machine learning and a practice loop for information exchange between the physical factory and a virtual digital twin model to realize production control optimization. Unlike traditional production control approaches, this novel approach integrates machine learning and real-time industrial big data to train and optimize digital twin models. It can support petrochemical and other process manufacturing industries to dynamically adapt to the changing environment, respond in a timely manner to changes in the market due to production optimization, and improve economic benefits. Accounting for environmental characteristics, this paper provides concrete solutions for machine learning difficulties in the petrochemical industry, e.g., high data dimensions, time lags and alignment between time series data, and high demand for immediacy. The approaches were evaluated by applying them in the production unit of a petrochemical factory, and a model was trained via industrial IoT data and used to realize intelligent production control based on real-time data. A case study shows the effectiveness of this approach in the petrochemical industry. 相似文献
15.
耕地资源既能产生生态效益,为整个社会提供生态福利,具有正外部性,同时也会因为不合理利用而损坏人类的福利,产生负外部效应。仅仅估算耕地的正外部性价值量,可能会高估耕地保护经济补偿额,不利于耕地保护政策的实施。本文以湖北省102个县(市、区)为例,分别测算了耕地的正外部性和负外部性价值量,进而得出耕地的净外部性价值量;此外,通过测算各区域内部的外部性需求量得出耕地保护的外部性盈亏水平,并据此实施跨区域的财政转移支付,以均衡各区域的发展。研究结果表明:①湖北省大部分地区的耕地对外界环境均起到了正面影响,但省内耕地资源的净外部性水平差异明显;②扣除区域内部的外部性需求量,湖北省共有41个县(市、区)耕地保护的外部性有盈余,属于财政转移支付受偿区;同时,共有61个县(市、区)耕地资源的外部性处于亏损状态,属于财政转移支付支付区;③财政转移支付行为具有一定的现实可操作性。各个县(市、区)的转移支付额占当年地方政府财政收入的比例较低,约为0.007%~5.030%,均在政府可承受的范围内。研究成果为耕地保护经济补偿政策的实施提供了一定的理论依据。 相似文献
16.
服务业创新轨道的形成机制及对追赶的战略意义 总被引：2，自引：0，他引：2
随着中国融入全球经济一体化进程,和制造业一样,中国服务业也处于一个追赶者的位置。如何在开放的环境下成功实现追赶,是中国服务业面临的一个重要挑战。对于追赶企业来说,创新轨道及其背后的技术经济因素对能否成功实现追赶有着重要影响。提出了一个分析服务业创新轨道形成机制的理论框架,并以电信业和零售业为对象进行了实证研究。重点探讨了服务业特性在创新轨道形成过程中的作用机制及对追赶的战略意义。 相似文献
17.
We inductively develop a model of the commercialization process for new products or services user entrepreneurs undertake when entering an industry while drawing on proprietary technology developed in another industry. Extending the growing field of user entrepreneurship, we identify a two-phase approach to industry entry by user entrepreneurs who start “under the radar” of incumbent firms, gain experience, attract a first potential customer base, and then, in a second phase, engage in commercialization. During this process, a community of fellow users is of major importance for the entrepreneur, serving as a knowledge pool for skills development and experimentation with different commercialization paths. We study a nascent group of firms founded by users of video games who became entrepreneurs on entering the animation industry by producing Machinima, a new film genre characterized by shooting film in video games. We explain how user entrepreneurs gain access to complementary assets (video games) for their new use (shooting film), how they deal with intellectual property issues when using other firms’ assets, and how user entrepreneurs combine domain knowledge about film production with their experience in video games and the art of Machinima. Our propositions hold implications for management and policy. 相似文献
18.
【目的/意义】大数据互联网时代,知识以碎片化形式分散在大数据环境中,加剧了大知识融合的难度,深刻 地影响了知识的组织和创新过程。如何针对大数据环境下碎片化知识的特征,构建出适于系统性的把握知识和解 决复杂问题的知识融合框架就成为大数据知识工程研究的热点问题。【方法/过程】系统性分析了碎片化知识的特 征,在此基础上构建了基于知识超网络的融合框架,探讨了知识融合的标准、知识融合的维度以及知识融合的机 制。【结果/结论】知识超网络模型是碎片化知识非线性融合的一种可行的研究框架,其面向问题的多维、多级、多层 的综合的知识融合模型为大数据环境下碎片化知识的融合提供了新的思路。 相似文献
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“蒙氏教学法”作为一种经典的优秀幼儿教学法,在国外的幼儿教学中发挥出至关重要的作用,对幼儿教学活动产生了深远的影响。为了进一步提升我国幼儿教学质量,为国家培养更多的人才,我们需要更加积极地借鉴“蒙氏教学法”的先进教育经验,在中国化实践中加以改进,使其更加适合我国幼儿教育的现实情况,推动我国幼儿教育水平迈上新的台阶。 相似文献