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91.
通过对无人机互通互联互操作等通用化测控系统的研究,提出了基于VPX架构的无人机测控终端综合化开放平台技术,通过采用标准化、通用化硬件模块,软件设计统一规范和标准,嵌入第三方软件,实现任务功能协同开发。该技术可以支持陆态、海态、陆海态等多种不同体制平台任务的任意加载,为实现地面站与地面站、地面站与舰面站、舰面站与舰面站之间的多站一机管控切换提供了有力支撑,有效增强了无人机系统跨域作战的能力。同时,系统能够满足无人机多类型、多型号不断扩展的需求,减少无人机测控装备种类,降低新型无人机系统装备建设成本,提升了无人机系统的生存性、灵活性和作战效能。  相似文献   
92.
食品质量安全直接关系到广大消费者的身体健康和生命安全。食品质量安全除受环境污染或天然存在外,还有很多是由于不法商人在食品生产加工中以次充好,人为造假,违章作业等造成的。极大损害广大消费者利益、影响经济发展和社会稳定。本文分析了当前食品质量安全存在的主要问题及其危害,提出探讨解决食品质量安全问题的一些设想建议。  相似文献   
93.
企业在进行管理安全和风险时,以风险为基础的方法用于管理检查和维修工作是最近十年出现的一种优化资产费用的工具。这个较先进的量化方法有可能预知装置风险程度的检查结果,并且有助于开发优化的检查计划。这些方法,由于综合软件解决方法的开发,现在已经开始变得成熟。综合软件解决方法能够与设备数据库交换信息,能够管理检查计划和维修计划的实施,以及永久保持资产和检查的数据。 本文介绍中东地区对近岸装置实施这种综合RBI和检查系统的情况。根据详细的RBI分析和过去的检查记录,对所选择的设备进行现场无损检测技术(NDT)的检测。资产数据、检查记录和文档集中保存在计算机化的系统中。该系统有能力存储和审查各种类型的文档和图样。这个系统还可能生成和监测检查和维修工作单,并且能够与其他企业系统进行交流。知识数据库对全部资产的活动很有用处。与MS Exel输入输出功能进行数据交换也很方便。  相似文献   
94.
浅议低碳旅游与旅游企业的低碳举措   总被引:6,自引:0,他引:6  
曹会林 《价值工程》2010,29(4):31-31
在后工业化时代,节能环保与经济持续发展将成为新的主题。在全球提倡发展低碳经济的形势下,低碳旅游这一新型的旅游生活方式逐渐被人们接受。旅游企业在低碳经济发展过程中将起到积极的推动作用。旅游企业通过旅游服务理念提升,旅游产品设计,旅游接待设施的改善,旅游方式的引导等手段将低碳旅游转化为旅游者的行动。  相似文献   
95.
Internet retailers often compete fiercely for consumers through expensive marketing efforts like search engine advertising, online coupons and a variety of special deals. Against this background, it is somewhat puzzling that many online retailers have recently begun referring their website visitors to their direct competitors. In this paper, using an analytical model, we examine this counterintuitive practice and posit that an entry deterrence motive can potentially explain this marketplace puzzle. Specifically, we develop a model where two incumbents compete for consumers” business while facing a potential entrant who is deciding whether to enter the market. In addition to setting the price, each incumbent firm could potentially display a referral link to its direct competitor. Our analysis reveals that when confronted with a potential entry, an incumbent may refer consumers to its competitor, intensifying the market competition that could result in shutting off the entrant. Furthermore, we show that when referral efficiency is exogenous, it is possible that in equilibrium only one incumbent refers its customers to competitor (i.e., one-way referral) or both incumbents refer their customers to each other (i.e, two-way referral). When referral efficiency is endogenous, the ex-ante symmetric incumbents may choose asymmetric referral efficiencies ex-post. We extend the model in a number of directions including making the entrant share endogenous and allowing incumbents to be asymmetric. Overall, our results indicate that firms may be motivated by entry deterrence to voluntarily refer consumers to their direct competitors even when they are paid nothing for the referral.  相似文献   
96.
创业不仅是经济持续增长的动力,也是新常态下我国经济增长方式转变的重要源泉。从个人社交指数和风险倾向着手,分析其对个人创业的影响,同时考虑政府干预、市场成熟度和产权保护水平对社交指数和风险倾向与创业之间的调节作用,并将个人特质和区域因素作为控制变量纳入分析框架,运用CGSS 3年的数据进行实证分析。结果表明,个人社交指数对创业具有正向影响,个人风险倾向对创业的影响存在区域异质性。在农村地区,个人风险倾向对创业活动具有正向影响,即风险倾向越高,创业概率越大;而在城镇,个人风险倾向对创业的影响为负。在制度环境层面,政府干预和市场成熟度对创业具有负向影响,产权保护水平与创业之间存在“倒U型”关系,制度环境对社交指数与创业之间的关系具有调节作用,较高政府干预力度和较低市场成熟度使社交指数与创业负相关,而产权保护水平的调节作用则较弱;制度环境对风险倾向的调节作用较弱。  相似文献   
97.
This paper reexamines broadly. from the standpoint of innovation, the arguments for vertical integration in the U.S. telecommunications industry in light of structural change since the breakup of the Bell System. While basic and applied research became the casualty of the 1984 breakup and the 1995 AT&T split, there is no evidence that the pace of innovative activity and productivity has slowed. Evidence from R&D and patent data suggests some acceleration of innovative activity. However. the service segment of the industry ceased to be the center of technological innovation. The source of future innovation seems to lie in the telecommunications and Internet equipment firms and independent software firms. The emergence of the competitive stand-alone software industry, combined with a trend towards open operating systems and customer demand for greater flexibility, and growing substitution of technology alliances for in-house R&D appear to have undermined the case for vertical integration in the telecommunications industry. From the standpoint of business strategy, the question of whether a firm like AT&T, notwithstanding its huge investments in cable facilities, can develop distinctive and sustainable capabilities through horizontal expansion and ubiquity and one-stopshopping marketing alone remains open.  相似文献   
98.
This paper reexamines the linkages between women's work, agency, and well-being based on a household survey and in-depth interviews conducted in rural Tamil Nadu in 2009 and questions the prioritization of workforce participation as a path to gender equality. It emphasizes the need to unpack the nature of work performed by and available to women and its social valuation, as well as women's agency, particularly its implications for decision making around financial and nonfinancial household resources in contexts of socioeconomic change. The effects of work participation on agency are mediated by factors like age and stage in the life cycle, reproductive success, and social location – especially of caste – from which women enter the workforce.  相似文献   
99.
Abstract

The generalized gamma distribution having the density function was introduced by Stacy (1962), who studied some of its properties. As observed by Stacy, many standard distributions are special cases of (1). For example d=p=1 gives the exponential, p=1 gives the gamma p=1 and d=n/2 (n is a positive integer) gives the chi-squared, and d=p gives the Weibull distribution. Furthermore, certain functions of a normal variable— viz., its positive even powers, its modulus, and all positive powers of its modulus, have Stacy's gamma form.  相似文献   
100.
Applied economists working with time series data face a dilemma in selecting between models with deterministic and stochastic trends. While models with deterministic trends are widely used, models with stochastic trends are not so well known. In an influential paper Harvey (1997 Harvey, AC. 1997. Trends, cycles and autoregression. Economic Journal, 107: 192201. [Crossref] [Google Scholar]) strongly advocates a structural time series approach with stochastic trends in place of the widely used autoregressive models based on unit root tests and cointegration techniques. Therefore, it is important to understand their relative merits. This article suggests that both methodologies are useful and they may perform differently in different models. This article provides a few guidelines to the applied economists to understand these alternative methods.  相似文献   
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