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121.
为了满足船舶自动识别系统抗干扰性能的要求,设计了一种机载阵列天线。天线阵列由5个单极子天线单元组成,整体尺寸为Φ720 mm×306 mm,天线单元沿圆周均匀排列。通过泰勒分布和牛顿优化算法,优化阵列的辐射幅度及相位,得到实测的方位面增益-15 dB抑制范围达到128°,-20 dB抑制范围达到77°;装机后-15 dB抑制范围在114°以上,-20 dB抑制范围在51°以上。该阵列天线结构简单,成本低,满足机载环境的使用要求。 相似文献
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In this paper, we present a practical methodology for variance estimation for multi‐dimensional measures of poverty and deprivation of households and individuals, derived from sample surveys with complex designs and fairly large sample sizes. The measures considered are based on fuzzy representation of individuals' propensity to deprivation in monetary and diverse non‐monetary dimensions. We believe this to be the first original contribution for estimating standard errors for such fuzzy poverty measures. The second objective is to describe and numerically illustrate computational procedures and difficulties in producing reliable and robust estimates of sampling error for such complex statistics. We attempt to identify some of these problems and provide solutions in the context of actual situations. A detailed application based on European Union Statistics on Income and Living Conditions data for 19 NUTS2 regions in Spain is provided. 相似文献
124.
Long Zhang Matt Dallas Jinhuang Hu 《International Journal of Human Resource Management》2018,29(20):2971-2999
AbstractDrawing insights from the group engagement model and self-determination theory, our research explored the role of perceived empowerment human resource (HR) practices in the hybrid organizational form of social enterprise in China. Based on two studies, this paper developed and examined a moderated mediation model, linking perceived empowerment HR practices, identification motivation, work engagement, and authority work value. Specifically, in Study 1 we found perceived empowerment HR practices increased employees’ work engagement through enhancing employees’ identification motivation. In Study 2, we adopted a two-wave design to duplicate and extend this mediation model. A moderator, employees’ authority work value, was found to weaken both the mediation relationship, and the positive relationship between perceived empowerment HR practices and identification motivation. This study broadens the understanding of what social enterprises look like in alternative contexts, while providing an opportunity to explore how a HRM mechanism and its boundary condition function in large social enterprises in China. 相似文献
125.
为了控制奥贝胆酸药品的质量,从奥贝胆酸原料药中分离并鉴定了3种有关物质:3α-羟基-6-乙基-7-酮-5β-胆烷-24-酸(A),3α,7α-二羟基-6-亚乙基-5β-胆烷-24-酸(B)和3α(3α,7α-二羟基-6α-乙基-5β-胆烷-24-酰基氧基)-7α-羟基-6α-乙基-5β-胆烷-24-酸(C)。分析了这些物质产生的原因并进行了设计合成,其结构经过核磁共振氢谱得以确认。研究表明,3个有关物质与奥贝胆酸粗品中的主要有关物质的相对保留时间完全一致,合成的有关物质与分离得到的有关物质的核磁共振氢谱图相符合,可以判定奥贝胆酸产品中的主要有关物质就是合成得到的有关物质A、有关物质B、有关物质C。解决了有关物质研究所需对照品的问题,提高了原料药的质量,为奥贝胆酸的质量研究和有关物质的控制提供了一定的帮助。 相似文献
126.
This study evaluates tourism experiences shared through electronic word-of-mouth (eWOM) across four Chinese attractions. The objective is to develop a framework for evaluating eWOM by constructing an indicator system and implementing an analytic hierarchy process with the use of a fuzzy comprehensive evaluation algorithm. This framework is achieved by mapping more than 6000 websites related to Chinese tourism attractions and filtering over 200,000 useful reviews to measure service performance. Results indicate that ecological–biological attractions failed to make tourists feel “very satisfied” in various aspects, such as overall evaluation, infrastructure, traffic, natural environment, and social environment. Overall, the study contributes by presenting a framework that can be adopted by tourism researchers and industry practitioners to understand tourist preferences and evaluate service performance to improve service quality. 相似文献
127.
Juan Carlos Martín Concepción Román Clara Gonzaga 《Journal of Convention & Event Tourism》2017,18(1):1-25
This article aims to evaluate the service quality experienced at academic conferences held at the Universidad Técnica Particular de Loja in Ecuador. Our approach is based on fuzzy logic and ideal solutions to calculate a global attendee satisfaction index for specific market segments: Gender, nationality, and age. Current literature on the service quality experienced by conference attendees is still scarce. Our results show that the analyzed segments experience varying levels of satisfaction, and that the more influential attributes to each of them are also different. Our results can be applied to improve the competitiveness of Loja and that of Universidad Técnica Particular de Loja. 相似文献
128.
Jen-Hung Huang 《Tourism Management》2012,33(2):456-465
This study proposes a novel approach, the Fuzzy Rasch model, which combines Item Response Theory (IRT) and fuzzy set theory. This paper applies the Fuzzy Rasch model in Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) to analyse the Tourism Destination Competitiveness (TDC) of nine Asian countries: China, Hong Kong, Japan, Korea, Malaysia, Singapore, Taiwan, Thailand and the Philippines. The study was conducted in 2009 using 6 criteria and 15 indices. The results demonstrate the feasibility of applying the Fuzzy Rasch model in TOPSIS to analyse TDC in Asian countries. In addition, the proposed model also provides an effective means of applying the MCDM method to study TDC. Furthermore, in 2009, the Asian countries were ranked from most to least competitive as follows: China, Japan, Hong Kong, Malaysia, Thailand, Singapore, Taiwan, Korea and the Philippines. 相似文献
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近年来,随着计算机技术的发展和一卡通系统的普及,各单位迫切需要通过信息化手段提高自己的管理水平和信息化建设水平,其中一卡通系统显得尤为重要。本方案将从整体规划,改变原来的传统方式,用一张卡方式替代原来的身份识别模式,实现持卡人在单位范围内的身份统一识别,方便所有工作人员,提升单位信息化建设水平。 相似文献