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141.
[目的/意义]实现海量产品评论数据的快速分析,帮助产品设计人员高效地获取用户需求,在新产品设计的决策中提供参考。[方法/过程]在特征提取和情感分析的基础上,构造了包括"词+词性+词干+位置+依存关系"等节点特征的条件随机场模型,按照"产品特征、谁、在何种情境下、遇到了什么问题"4个要素,以描述手机屏幕和电池的负面评论为例,从产品评论中提取用例。[结果/结论]模型评估和实证研究表明,所构造的模型可以有效地从评论文本中识别产品特征、使用主体、使用情景和遇到的问题,从而快速构造用例,获取用户需求。  相似文献   
142.
Information technology (IT) engagement is defined as a need to spend more time using IT. Practice-based examples show that IT engagement can have adverse effects in organizations. Although users can potentially get more work done through IT engagement, observations show that the users might jeopardize their well-being and hamper their work performance. We aimed to investigate this complexity in the research on IT engagement by examining its potential antecedents and outcomes in organizations. Considering the potentially mixed outcomes, we developed a model to examine the effects of IT engagement on personal productivity and strain. We also aimed to explain the antecedents of IT engagement by drawing on the collective expectations for IT use. In particular, we examined the extent to which normative pressure on IT use drives users’ information load and IT engagement. Finally, we sought to understand whether users’ attempts to avert dependency on IT use reduced their IT engagement. Several hypotheses were developed and tested with survey data of 1091 organizational IT users. The findings help explain the role of normative pressure as a key driver of IT engagement and validate the positive and negative outcomes of IT engagement in organizations.  相似文献   
143.
The purpose of this paper is to investigate factors influencing employees’ knowledge-sharing behavior on social tagging supported systems. Using the strong theoretical background of the well-known technology acceptance model (TAM), this paper proposes and empirically validates a model that fits the social and technical nature of social tagging tools within the public sector. The analyses in this paper were based on data collected from a large survey of more than 480 respondents working for two public organizations in the United States. The findings demonstrate a significant impact of the role of social presence in encouraging employees to create and share content. Further, there is a strong relationship between the benefits employees receive from using tagging tools and their creation and sharing of tagged content. Specifically, the following factors showed a significant impact on employees’ creation and sharing behavior, specifically their attitudes towards and intentions to create and share tags: perceived ease of use, perceived usefulness, social presence, and pro-sharing norms. For researchers, the paper offers an opportunity to further study knowledge-sharing behavior regarding social media technologies. The findings should motivate practitioners to inject these tools with a social aspect so that employees are encouraged to share content.  相似文献   
144.
当前信息服务机构已纷纷通过建立专题数据库为用户提供信息服务,而专题数据库的发布、使用方式则在很大程度上影响专题数据库的使用效果。首先讨论数据库的一般发布载体,主要有纸张I、nternet和光盘等;其次讨论了专题数据库光盘发布实现的技术、原理;最后给出了此技术的应用、实践实例。  相似文献   
145.
将日光温室进一步改造为内部成交叉双尖窄状的多重温室,使尖窄状内温度更高,从而使置于尖窄状内的太阳能集热器的热效率更高,达90%左右,并将这种特殊结构的温室安装在建筑物窗户外面下端的墙壁上,而热水箱则放于室内,并用软管与集热器相连通,就构成一种窗户型太阳能热利用装置.从而"将多重温室太阳能与建筑相结合,并且使用方式从房顶转向窗户",是一条新的技术路线.  相似文献   
146.
基于工业以太网的高炉监测系统,介绍了Modbus/TCP通信协议,以及由工控机、工业以太网、ADAM5000/TCP数据采集模块和传感变送器等组成的远程数据采集系统的构建,并通过编写VB6.0应用程序实时监测高炉生产工艺参数.  相似文献   
147.
减法工程疗法与清理内环境   总被引:1,自引:0,他引:1  
用十五年医疗实践,初步总结出“减法工程”疗法,是在针刺经络、断食辟谷后通过清除体内非实体性物质而使代谢障碍消失,以证明它和治理物质实体性毒物同样重要。  相似文献   
148.
最后航次问题是定期租船中一个常见的问题。英国、美国对最后航次的相关问题,包括还船日期的确定、合法航次与非法航次之分、承租人的赔偿等,都有完整的法律规定。我国在海商法中的相关规定较为模糊,存在合同法及海事实践的衔接问题,对出租人较为不利。  相似文献   
149.
李贽是我国古代一位杰出的思想家,他的思想对后世产生过重要影响.李贽对人才的标准、识人、用人等几个方面都有论述,他将"总足办事"作为衡量人才的主要标准.他不拘一格选用人才的思想有其合理性,对今天识人、用人仍不失参考价值.  相似文献   
150.
Objective:To evaluate the differences in presentation (formatting) of adverse drug reaction (ADR) information within drug monographs in commonly used drug information (DI) mobile device applications.Methods:A cross-sectional analysis of ADR formatting of twenty commonly prescribed oral medications within seven DI mobile applications was performed. Databases were assessed for ADR information, including presence of placebo comparisons, severity of ADR, onset of ADR, formatting of ADRs in percentile (quantitative) format or qualitative format, whether references were used to cite information, and whether ADRs are grouped by organ system. Data was collected by two study investigators and discrepancies were resolved via consensus.Results:The seven DI mobile applications varied significantly on every analyzed ADR variable with the exception of ADR onset, which was absent in all databases. Significant differences were found for variables known to impact clinical judgment such as placebo comparisons and qualitative versus quantitative formatting. Placebo comparisons were most common among monographs in Lexicomp (30%) but were absent among monographs within other applications. Quantitative information was commonly used in most databases but was absent in Epocrates. Qualitative formatting was present in all Epocrates and Micromedex applications but absent in the majority of other applications. Substantial variations were also found in severity and grouping information.Conclusion:Substantial variation in ADR formatting exists among the most common DI mobile applications. These differences may translate into alternative interpretations of medical information and thus impact clinical judgment. Health care librarians and clinicians should consider ADR formatting when choosing between DI applications.  相似文献   
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