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991.
地空数据通信系统的越区切换不仅要尽可能地减少切换次数,还要保持地面通信路由优化,以提高地空通信保障的可靠性。通过采用基于加速度的运动估计预测目标位置,并融合最短路径算法确定越区切换站点,在保证地空数据通信质量的同时提高了越区切换的效率,满足空中目标自由机动情况下的跨区域无缝通信要求。  相似文献   
992.
针对低信噪比下突发通信系统的同步检测问题,提出了一种利用接收信号平均信噪比和瞬时信噪比设置动态检测门限的同步方法,实现了信号检测门限的设置与信号脉冲出现时刻噪声能量的自适应匹配,提高了低信噪比下同步检测概率。计算机仿真表明在同步序列长度为63时,信号的有效检测工作信噪比可以降低到-5 dB。该方法适合于低信噪比下运动平台间的突发通信系统。  相似文献   
993.
认知无线电网络被认为是实现动态频谱共享、缓解频谱资源紧缺的重要途径。喷泉码能有效抵抗认知无线电网络中来自主用户的突发干扰,且无需反馈重传,从而为认知无线电网络提供了一种有效的信道编码方案。首先简介了数字喷泉码以及认知无线电网络基础知识,然后综述了数字喷泉码在认知无线电网络的链路建立、认知通信以及在资源分配中的应用现状,最后指出了在这一研究领域中需要解决的问题,并展望了发展前景。  相似文献   
994.
针对短波通信中无法避免的码间串扰问题,研究了聚类算法在信号调制识别中的作用,提出了一种利用广度优先搜索邻居(BFSN)聚类处理循环统计量特征的分类算法。该算法将循环统计量特征峰值作为聚类输入对象,通过BFSN聚类分析,剔除延时信号、噪声等造成的奇异类峰值,克服了多径效应产生的码间串扰影响,实现了2FSK、4FSK、BPSK、QPSK、16QAM、π/4-QPSK、π/4-DQPSK、8PSK等8种调制信号的自动识别。仿真表明,该算法聚类后提取的特征参数抗多径干扰能力强,同信道均衡方法相比识别正确率有5%的性能优势。低信噪比环境下的信号调制识别具有重要的工程应用意义。  相似文献   
995.
Abstract

This paper examines the influence of an authentic assessment item on three dimensions of oral communication in accounting education: skills, self-efficacy, and relevance. An explanatory mixed methods design is used to explore students' perceptions of their development. The results indicate that an elevator pitch assessment has a positive impact on all three dimensions. In particular, the employed video technology fosters greater self-awareness and a more accurate perception of skill levels, and enhances students' self-efficacy. The contextualised learning experience also enables students to better appreciate the relevance of oral communication to their future careers. The paper extends the literature on video technology, self-efficacy, and generic skills development in accounting education, and provides relevant stakeholders with evidence of an authentic activity that can assist with bridging the skills-expectation gap.  相似文献   
996.
This study investigates the mediating mechanisms through which relation-specific investments (RSIs) can contribute to channel performance in China. We distinguish between property-based RSIs and knowledge-based RSIs and propose that these two types of RSIs rely on different governance mechanisms to impact channel performance. Specifically, although property-based RSIs prompt the drafting and utilization of formal contracts, they promote channel performance through relationship communication. In contrast, knowledge-based RSIs enhance relational trust and relationship communication, which can increase the profitability of the channel relationship. However, both types of RSIs can enhance channel performance directly. Our study shows that relationship communication plays an important role in strengthening the effects of governance mechanisms for both types of RSIs in China. In addition, relational governance mechanisms have greater effects than formal contracts on channel performance. These results enrich our understanding of RSIs in the emerging market.  相似文献   
997.
Brand orientation has been recognized as having a positive impact on organizational performance in both commercial and nonprofit sectors. However, limited studies have examined the moderating effects of brand orientation in the nonprofit sector, particularly in the higher education context. This study attempts to examine the construct of brand orientation from the perspective of the students and examine its moderating role on the relationship between service quality, satisfaction, loyalty, and word-of-mouth (WOM) communication behavior. Two hundred and fifty-eight questionnaires were completed by undergraduate students of an Australian university. The study found that students’ perception of a university’s brand orientation significantly moderates the relationship between service quality, loyalty, and WOM communication behavior. Significant managerial and theoretical implications were identified.  相似文献   
998.
Corporate social responsibility (CSR) has gained global awareness in recent years. The proponents of CSR state that a good corporate reputation may be beneficial to an organization. This research paper reviews the theoretical basis of CSR, and by adopting a qualitative methodology examines the characteristics of CSR strategies and CSR communication tactics of eight companies in Cyprus market through personal in-depth interviews. Results reveal that CSR has a positive impact on the company's employees, the environment, stakeholders and the general public, and highlight that CSR is an important ingredient for the success of the organizations in the Cyprus market.  相似文献   
999.
Companies operating across borders face greater challenges in ensuring compliance with company strategy in different cultural contexts. Recent research shows the cognitive and emotional benefits of utilizing visual representations of knowledge in organizations. This study aims to test if mapping a corporate strategy visually can improve attitudes toward firm strategy and the intention to comply with it. An experiment is conducted comparing two knowledge maps to a textual version of the same company strategy. In order to measure attitudes toward the strategy, a scale was developed and tested in Europe and China. The study outcome provides a parsimonious and effective tripartite scale of attitude with cognitive, affective and behavioral components. The scale was then applied to a different sample to test the effect of mapping a company strategy visually on attitude toward the strategy, and to test if the effect is persistent in Europe and China. The results of the experiment show that subjects exposed to the visual conditions had significantly more positive affective and cognitive attitudes toward the content.  相似文献   
1000.
为了最大程度地利用资源和减小电磁干扰,电子战平台的雷达通信一体化设计有着尤为重要的意义。针对通信中成熟应用且在雷达中有较好前景的正交多载频波形,提出直接序列扩频正交频分复用(OFDM)进行雷达通信一体化的想法。给出了实现方法,重点对该一体化信号模糊函数进行求解和分析,指出增加子载波数目信号分辨性能更佳;随机的信息流仅对模糊函数的邻道干扰项造成影响,为进一步优化一体化信号旁瓣性能提供了理论依据。最终的仿真结果和性能分析表明,该一体化信号能够实现雷达通信一体化的目的。  相似文献   
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