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21.
通信信号的识别与解调是通信侦察的重要研究内容,在通常情况下,通信信号的很多参数并不知道。本文介绍了一种基于通信信号码延迟自相关特性的码速率测量技术,并给出了码速率测量理论分析及基于硬件的实现技术,仿真和实验结果表明本方案具有较高的测量性能。  相似文献   
22.
鸡蛋壳制备乙酸钙冰雪融化剂的研究   总被引:5,自引:1,他引:4  
以鸡蛋壳为原料,对高温煅烧分解蛋壳、中和法制备乙酸钙(CA)的最佳反应条件进行了研究,试验结果表明:在所选参数下,其产量最大.即反应温度为50℃,配料摩尔比为CaO:HAc=1:2.8,乙酸浓度为15 mol/L,石灰乳浓度(以氧化钙计)为1.3 mol/L.产品融冰试验表明:CA在环境温度为-10℃以上使用时,其融冰效果较好.  相似文献   
23.
陈鑫远  赵林度 《物流技术》2005,(10):213-215,219
提出了基于无线射频技术(RFID)的零售企业生鲜食品的信息追溯技术和持续补库计划(CRP)策略,集成了整合发货和库存补货,并构建了用以计算最高库存量和配送周期的供应商管理库存模式下的补货数学模型,模型中充分考虑了生鲜食品的特性(腐坏),确保零售企业销售生鲜食品的质量安全.在通过采用RFID技术实时监控销售和库存数据的基础上,供应商能够依据模型在发货周期内确定最佳的货物配送时间和配送数量,主动补货,在保证食品安全的同时实现总的长期平均成本最小化.  相似文献   
24.
On Conditional Density Estimation   总被引:1,自引:0,他引:1  
With the aim of mitigating the possible problem of negativity in the estimation of the conditional density function, we introduce a so-called re-weighted Nadaraya-Watson (RNW) estimator. The proposed RNW estimator is constructed by a slight modification of the well-known Nadaraya-Watson smoother. With a detailed asymptotic analysis, we demonstrate that the RNW smoother preserves the superior large-sample bias property of the local linear smoother of the conditional density recently proposed in the literature. As a matter of independent statistical interest, the limit distribution of the RNW estimator is also derived.  相似文献   
25.
Characterization and construction of optimal designs using the familiar optimality criteria, for example A-, D- and E-optimality are well studied in the literature. However the study of the Distance Optimality (DS-) criterion introduced by Sinha (1970) has very recently drawn attention of researchers. In the present article, we consider the singularly estimable full rank problem of estimating the full set of elementary treatment contrasts using the DS optimality criterion in the set up of a one way ANOVA model. Using a limit argument it turns out that a CRD in which difference between any two allocation numbers is at the most unity is uniquely DS-optimal. Acknowledgement. We are thankful to Prof. B. K. Sinha for suggesting the problem to us and many helpful discussions with him. We are also thankful to the referees for drawing our attention to the reference of Bischoff (1995) and many helpful comments.  相似文献   
26.
Adapted from Chan's (2000) model depicting success of litigation, this paper argues that with the application of various legislation, health maintenance organizations' (HMOs') violations of service fairness to each group: enrollees, physicians, and hospitals give rise to each group's lawsuits against the HMOs. Various authors (Bowen et al., 1999; Seiders and Berry, 1998) indicate that justice concepts such as distributive, procedural, and interactional justice can be applied to the area of service fairness. The violation of these underlying justice principles with HMOs' service unfairness to enrollees, physicians, and hospitals is examined. A general synopsis of the ethical issues in the managed care industry is provided. The various lawsuits launched by each group: enrollees, physicians, and hospitals together with the key statutes used are discussed. This paper also highlights the provisions and ramifications of the 11 April 2000 landmark agreement that Aetna made with Texas Attorney General John Cornyn to settle the 1998 lawsuit brought against the company. Lastly, the current ethical issues in the managed care industry are further discussed. The value of this paper can be adapted to the study of organizations' service fairness violations in other industries or in the educational, governmental, and not-for-profit sectors both nationally and internationally.  相似文献   
27.
中国大中型造纸企业技术创新机制探讨   总被引:1,自引:1,他引:0  
陈健  毛霞 《林业经济问题》2002,22(3):145-150
建立和健全大中型企业以技术创新为核心的技术进步的内在机制 ,保障提高技术创新的绩效是目前亟待解决的问题。本文根据 2 0 0 0年中国科技统计年鉴中的数据 ,对大中型造纸企业在技术创新方面存在的主要问题进行分析 ,就如何完善其动力机制和运行机制提出建议  相似文献   
28.
谢宏维 《中国农史》2003,22(2):116-122
从明后期开始进入徽州地区的外地棚民,利用当地丰富的自然资源,进行各种经济活动。在当时的社会条件制约下,此类经济活动耗费了大量的资源,破坏了徽州农村的生态环境,损害了地方和国家的利益。针对这一问题,清代徽州乡村社会各种民间力量和官方联合展开了一场声势浩大的驱禁棚民运动,取得了预期效果。  相似文献   
29.
本文综述了混合拉曼/掺饵光纤放大器(HFA)的工作原理,结构和特点,介绍了4类HFA基本结构及其实验结果,并通过介绍近年来各类HFA在密集波分复用(DWDM)系统中的应用表明了HFA在带宽,增益和噪声特性方面的优点。  相似文献   
30.
Advances in technology have impacted accounting careers with resulting changes in where, when and how accountants perform their job duties. In addition, employee attitudes towards, and need for, better work/life balance has led to more firms offering alternate work arrangements (AWA). Research suggests that AWA programs can lead to many benefits for both employers and employees. Despite the prevalence of these programs there are relatively few accountants working under these arrangements and concerns about work/life balance continue. This study examines factors that shape perceptions of the cost and benefits associated with the adoption and/or support of AWAs across work culture, gender and participation experience. Our results suggest that work environment had a significant effect on perceptions of AWAs. Public accountants perceived greater costs related to career advancement but correspondingly less concern about administrative issues than management accountants. We also found that accountants who have participated (or are currently participating in an AWA), perceived greater benefits and less concern for potential negative consequences to their careers than non-participants. Finally, women perceived greater benefits to result from participation in an AWA and men perceived correspondingly more costs. Regardless, both genders perceived that AWAs were not strictly a women's issue. These findings contribute to our understanding of alternate work arrangements and point to factors that must be addressed to increase the acceptance and success of these programs.  相似文献   
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