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排序方式: 共有1940条查询结果,搜索用时 15 毫秒
911.
本文讨论了喷墨印刷氧化铟锡(ITO)电极在有机太阳能电池(OSCs)中的应用。利用纳米ITO晶体进行喷墨印刷并在450℃时迅速退火,可以直接获得平均透光率为84.14%、方块电阻为202.7Q/口的ITO电极。由喷墨印届4直接制造的ITO电极制备的有机太阳能电池具有0.57V的开路电压、8.47mA/cm^2的短路电流、44%的填充因子以及2.13%的能量转换率。这表明从有机太阳能电池印刷成本效益来讲,相对于溅射工艺,由于无须光刻工艺且ITO材料的利用率更高,直接利用喷墨印刷制备ITO电极成为一种可行的选择。  相似文献   
912.
介绍了一种新型PHS基站信号再生设备的设计与实现方法,完成了该系统的硬件模块设计和软件设计及编译,并对软件流程进行了详细的介绍。该系统主要采用小灵通基带芯片ML7338(ARM7TDMI核)和RDA5206射频模块,实现对射频信号的解调,同时对基带信号重新编码再调制发射,很好地解决了普通直放站射频干扰问题。所设计的信号再生设备能实现对PHS信号的变换与转发,能够有效解决当前小灵通网络的盲区问题。  相似文献   
913.
微分几何在圆环面轴测图中的应用   总被引:2,自引:0,他引:2  
运用微分几何原理 ,通过分析其等距线特征 ,确定圆环面轴测图的形状 ,并提出了一种用经线圆包络线法画圆环面轴测图的一种方法。  相似文献   
914.
In order to enhance the independent innovation capability and help China to become an “innovation-oriented country” this article compares the spatial distribution of innovative activities between China (representing a typical developing country) and the United States. We also provide some recommendations for China and other developing countries to optimize the spatial distribution of their innovative activities. Using invention patents as an indicator gathered from the websites of the CSIPO and the USPTO, this paper compares the spatial distribution of innovative activity in China and the U.S. by methods such as rank-frequency, concentration and classification. The results show that the invention patents have experienced rapid growth and significant fluctuation in recent years in China, while the United States has been relatively stable. The spatial diversity of patent distribution in China is more obvious than in the United States. There is a concentrated trend of innovative activities in both China and the United States from the inland areas to the coastal regions.  相似文献   
915.
A conceptual framework intended to predict the number of online purchases made by Internet users in an early stage market is presented and examined using data collected in Israel. Those more likely to report buying online saw low costs and substantial benefits associated with e-shopping. They were experienced Internet users who valued online information searching. They were also more likely to shop over the phone, but did not especially like to go shopping. Finally, they tended to be the primary purchaser in the household. Our framework enhances understanding of the factors affecting consumers' online shopping behaviour, aides in profiling typical electronic shoppers, and may help practitioners develop more personalized marketing programs to increase e-commerce sales. Copyright © 2009 ASAC. Published by John Wiley & Sons, Ltd.  相似文献   
916.
The comparison of corporate social performance with corporate financial performance has been a popular field of study over the past 25 years. The results, while broadly conclusive of a positive relationship, are not entirely consistent. In addition, most of the previous studies have concentrated on large-scale cross-industry studies and often with a single variable for corporate social performance, in order to produce statistically significant results. This weakens the richness of understanding that might be obtained from a single industry study with multiple social variables, which would also allow investigation of inter-relationships between individual and sub-sets of social performance measures and between individual and sub-sets of social performance and financial performance measures. There have also been criticisms that the results lack a rigorous theoretical basis, and the paper demonstrates clearly how stakeholder theory must form the basis for this area of research. Following a review of the literature this paper presents the initial findings from a study of the U.K. Supermarket industry which suggest that contemporaneous social and financial performance are negatively related, while prior-period financial performance is positively related with subsequent social performance. Positive relationships between both age and size of the company with social performance are also found.  相似文献   
917.
Whilst there is a growing volume of literature exploring the ethical implications of organisational change for HRM and the ethical aspects of certain HRM activities, there have been few published U.K. studies of how HR managers actually behave when faced with ethical dilemmas in their work. This paper seeks to enhance the foundations of such knowledge through an examination of the influence of organisational values on the ethical behaviour of Human Resource Managers within a sample of charities in the U.K. and the Republic of Ireland. A qualitative research design is adopted utilising semi-structured interviews. Findings highlight ethical inconsistency in people management in the charity sector arising from the clear application of strong and explicit organisational values to external client groups but their limited influence on people management strategies and practices within the organisation. Many of the ethical issues faced by HRM professionals in both countries arise from this inconsistency. In their handling of ethical dilemmas, the HRM professionals exhibit a combination of a care ethic and a concern for justice but it is also clear that in situations of management intransigence, a desire to be conscience driven often gives way to a contingent approach. Whilst respondents considered it inappropriate for the HRM function to be the conscience of the organisation, it is seen to have a key role in providing management with advice on ethical action. However, the ability of HRM to influence ethical behaviour is highly dependent on the status of the function within the organisation.  相似文献   
918.
在分析东北地区快速客运网现状及其发展的基础上,根据该地区既有铁路条件及客货运市场竞争趋势,提出了对东北铁路第二条南北干线进行提速改造,并对其提速改造的必要性和方案的可行性进行了分析和探讨。  相似文献   
919.
声学定位技术的发展速度非常快,其应用也越来越广泛。当前大多海洋工程,如海洋油气开发、深海矿藏资源调查、海底光缆管线路由调查与维修等,需要声学定位系统(acousticpositionhagsystern)对水下拖体进行导舷定位,如水下遥控机器人ROV(remotelyop-eratedvehicle)、水下无人及其人UUV(umxtannedunderwatervehiCie)、水下自动机人AUV(autonomousunderwatervehicle)、声纳设备的水下拖鱼(towfish)等。本文就声学定位导航系统的发展现状、声学定位系统的原理、分类、不同类别的优绕点以及系统的技术发展等进行简单的研完。  相似文献   
920.
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