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1.
本文介绍了卫星通信地球站终端技术的发展过程,初步论述了新技术应用的环境,为今后研制卫星通信设备提供某些参考。  相似文献   
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本文主要讨论自适应调制与编码系统(Adaptive Modulation and Coding system)的原理,介绍AMCS实现的几个关键技术,包括RCPT(速率适配凿孔turbo)码、高阶调制、H-ARQ和MIMO(多输入多输出)系统。介绍了在WCDMA的高速下行分组接入业务(HSDPA)中使用的自适应调制编码机制,并讨论了可能增加的设备复杂度。  相似文献   
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We characterize the set of communication equilibrium payoffs of any undiscounted repeated matrix-game with imperfect monitoring and complete information. For two-player games, a characterization is provided by Mertens, Sorin, and Zamir (Repeated games, Part A (1994) CORE DP 9420), mainly using Lehrer's (Math. Operations Res. (1992) 175) result for correlated equilibria. The main result of this paper is to extend this characterization to the n-player case. The proof of the characterization relies on an analogy with an auxiliary 2-player repeated game with incomplete information and imperfect monitoring. We use Kohlberg's (Int. J. Game Theory (1975) 7) result to construct explicitly a canonical communication device for each communication equilibrium payoff.  相似文献   
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介绍了西门子S7-300 PLC和KEB伺服驱动器在非织造布设备交叉铺网机中的应用,着重介绍PLC控制系统的配置方案、软件设计思想,PROFIBUS通讯等.  相似文献   
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This article explores the potential of the SDG framework for interdisciplinary research. The aim is to illustrate the process of creating a shared platform of operation by the clarifying the positive and negative interactions between societal demands for land use on a national and local level. The research question is answered by making use of the systemic approach introduced by Niklas Luhmann including his arguments about autopoietic communication systems reproducing themselves. An interdisciplinary research group is firstly applying the SDG framework to the demands for sustainable land use by activating the land consolidation in Denmark. By doing so a ‘national framework’ anchored in the SDG framework is created. Secondly, the national framework is applied to a multifunctional land consolidation project in a Danish case area. The findings from the mapping of interactions between societal demands on a concrete case area revealed that some indicators and societal demands are more prone to conflicts than others but also on the local level there may be variations. Thus, a localised and contextualised SDG framework has shown useful insight for future projects on sustainable land use including land consolidation projects. The paper concludes that the SDG framework may be used for facilitating interdisciplinary research, however there is also a need for guidelines and examples on how to integrate the framework in academia. The paper offers a suggestion for integrating the Agenda2030 and the SDG framework in projects about sustainable land use.  相似文献   
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移动通信信号自动调制识别的谱相关方法   总被引:1,自引:0,他引:1  
一些不同的数字调制信号有着相同或相近的功率谱密度,但它们的谱相关函数却有明显区别。平稳的噪声和干扰的谱相关为零。利用谱相关函数的这些性质可以识别出噪声中的调制信号。本文提出了一种用于移动通信信号自动调制识别的谱相关算法,该方法可以识别各种主要无线系统和标准所采用的调制类型。  相似文献   
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One third of food destined for human consumption is wasted globally, and much of the food waste that comes from high-income or developed countries is caused by poor marketing practices, consumer behavior, and consumption patterns. The present study focuses on developed countries to propose some marketing actions that could help in reducing food waste. A comprehensive analysis was carried out for each marketing variable, to provide a snapshot of actions and proposals that are being developed. Our study highlights the relevance of marketing in contributing to reduce food waste, through the removal of “Buy one, get one free” sales promotions, clarifying date labeling, or raising food waste awareness campaigns. The main contribution of this study is the proposal of marketing actions that help in tacking food waste.  相似文献   
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Within the professional kitchen bullying is reported as widespread, aggressive and related to a significant retention problem. This research explores negative behaviour in professional kitchens and its impact on organisational commitment. A mixed methods approach is used employing a survey among chefs followed by semi-structured interviews. An exploratory factor analysis examines the underlying constructs of bullying and job satisfaction and data are analysed through Partial Least Squares. Our research highlights that bullying behaviour is experienced most by younger, more junior chefs. However verbal bullying, the form most strongly reported, has no effect on either satisfaction or commitment. Emergent themes of communication and inclusion illustrate bullying behaviour to be a cohesive aspect of kitchen culture. Our findings suggest behavioural impacts, rather than bullying characteristics, must be considered within their context in order to establish whether or not they are actually damaging to an industry.  相似文献   
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