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1.
孙金波 《科技和产业》2021,21(4):284-289
国产某型民用通勤类飞机为了取得欧洲航空安全局(EASA)型号合格证,机上座椅需进行设计更改并补充进行应急着陆情况下的动态要求符合性验证.通过对适航条款及相应标准的解读,研究了基于动态试验的航空座椅动态要求适航验证技术,其主要包括座椅动态性能基本要求、试验构型及工况筛选、试验规划、合格判据和试验结果分析等内容.结果表明,该型机旅客座椅满足适航规章对座椅的动态性能要求.该项旅客座椅动态性能试验的成功为型号取得EASA型号合格证奠定了良好的基础,该型飞机也即将成为第一个取得欧洲型号合格证的国产飞机.  相似文献   
2.
组网是卫星、无人机等飞行器集群实现协同的基础。传统自组织组网技术针对地面随机移动场景设计,不适用于拓扑和传输根据任务变化的飞行器集群场景,为此设计了一种管理与任务分离的组网方法,将网络分为管理面和任务面两个逻辑层面,管理面负责拓扑发现、路由建立、任务规划等基础组网功能,任务面负责任务执行过程中的数据传输功能。管理面和任务面实行不同的组网策略,从而使得网络的传输性能根据管理和任务执行的不同需求进行优化,以减少协议开销及降低传输自干扰。  相似文献   
3.
Some agents are more accurate than others in estimating the best policy. The more accurately an agent estimates a policy's effects, the more he will resist biases, such as bribes from a special interest. Thus, a special interest needs to pay a larger bribe to an accurate agent than to an inaccurate agent. The accurate agent who is biased will then more likely cause harm than does an inaccurate agent who favors the special interest. Therefore, the principal may gain more from controlling biases of an accurate agent than of an inaccurate one. Thus, high ability of public officials may be associated with little corruption.  相似文献   
4.
We study the optimal execution problem with multiplicative price impact in algorithmic trading, when an agent holds an initial position of shares of a financial asset. The interselling decision times are modeled by the arrival times of a Poisson process. The criterion to be optimized consists in maximizing the expected net present value of the gains of the agent, and it is proved that an optimal strategy has a barrier form, depending only on the number of shares left and the level of the asset price.  相似文献   
5.
近几年来,民营经济在我国经济中的地位越来越突出。该文在分析家族制管理模式的利弊及其对企业财务管理影响的基础上,对中小型民营家族制企业财务管理存在的问题及改善对策进行了探讨。  相似文献   
6.
深化乡镇综合改革难点研究   总被引:3,自引:1,他引:2  
乡镇机构人员膨胀是当前农民负担过重的主要原因之一。而20多年来乡镇机构减而复胀且日益严重,成为改革的难点。乡镇职能错位、各类机构关系不顺、社会改革不配套,还有行政机构中客观存在的“帕金森定律”,是乡镇机构改革难点形成的深层原因。深化乡镇综合改革的远期目标是实现乡镇自治,而近期目标则是以转变职能为核心,调整政府管理体制;实现乡镇机构的功能整合;同时可以实行政府职能“外包”;还要加强机构编制的法治管理。  相似文献   
7.
A conceptual framework of anonymity in Group Support Systems   总被引:2,自引:2,他引:0  
As the development and use of automated systems for collaborative work grows, the need for a better understanding of these systems becomes more important. Our focus is on one type of system, a Group Support System (GSS) and, in particular, on one important aspect of a GSS—anonymity. A conceptual framework for the study of anonymity in a GSS is presented, which describes the general classes of variables and their relationships. These variables include the factors that influence anonymity in a GSS, types of anonymity, and the effects of anonymity on a message sender, receiver, group process, and outcome. Each of these variables is discussed with working propositions presented for important group process and outcome measures. The objectives of this article are to highlight the importance and complexity of anonymity, to act as a guide for empirical investigations of anonymity, and to influence future GSS development and use.  相似文献   
8.
对可行性研究报告及经济评价的几点认识   总被引:1,自引:0,他引:1  
指出在建设项目前期工作中存在的问题,建设项目前期工作滞后,前期方案深度不够,需对可行性研究报告及项目经济评价的方法与参数进一步完善,重视风险问题及清偿能力分析,提高技术经济人员的综合分析能力,实现投资决策科学化,提高经济效益。  相似文献   
9.
Consumer spending over the life span of today's 18‐ to 25‐year‐old emerging adults will reach into the $10 trillion range. Emerging adults are a powerful force in shaping demand for consumer products. The problem recognition styles associated with emerging adults can help marketers understand this group of consumers and provide insight into what kinds of products, services, and messages will appeal to them as lifelong consumers. The purpose of this study was to examine differences between men and women and among fashion consumer groups in fashion problem recognition style. Participants were a convenience sample of emerging adult consumers from one Midwestern university in the US, 136 men and 158 women who completed the Measure of Fashion Innovativeness and Opinion Leadership, Fashion Problem Recognition Style Scale, and provided demographic information. Both fashion followers and men reflected a need‐based approach to problem recognition. Both fashion change agents and women reflected a want‐based approach to problem recognition. Male fashion followers differed from all other groups in indicating a need‐based approach to problem recognition. This study built on previous work by examining differences in problem recognition style owing to fashion consumer group and gender. The basic premise behind problem recognition style was validated; that is, actual state (need‐based) vs. ideal state (want‐based) approaches to fashion problem recognition did relate to fashion consumer group membership and gender.  相似文献   
10.
This article discusses changes in approach to the study of business relationships, and sees the paradigm concept as constituting an inadequate basis for describing gradually evolving changes in the perception of business. The frequent references to paradigms appear to focus more on state aspects than on change aspects of theory building. The article attempts to trace some of the changes in the perception of markets preceding the emergence of network theories, and relates the presence of an interactional approach to business studies to the concept of problem shifts (Lakatos). The development of interactional approaches in marketing is seen as representing a shift away from theory building commonly found in economics and organizational theory. Changes in the approach to the study of business relationships are interpreted as theoretical or empirical problem shifts, and are thus related to the a priori and a posteriori relevance of the continual evolution of alternative business theories. The article explores some of the epistemological relevance of the network theories to the study of market relationships, and the potential impact on continual changes in approach to the study of markets.  相似文献   
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