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41.
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   
42.
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   
43.
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   
44.
新形势下我国耕地保护的长效机制研究   总被引:1,自引:0,他引:1  
耕地是人类赖以生存的物质基础,是国民经济和社会发展的宝贵资源,耕地数量的多少和质量优劣直接关系到国家粮食安全和社会稳定。因此,在新形势下,如何保护好有限的耕地资源,促进经济社会科学、合理地发展,已成为当今世界的重大课题。本文根据我国耕地减少的现实危机及原因,提出一套科学、合理的耕地保护长效机制,力求为进一步有效地保护耕地资源提供理论基础和现实途径。  相似文献   
45.
Using data from the Frankfurt Stock Exchange we analyze priceformation and liquidity in a non-anonymous environment withsimilarities to the floor of the NYSE. Our main hypothesis isthat the non-anonymity allows the specialist to assess the probabilitythat a trader trades on the basis of private information. Heuses this knowledge to price discriminate. This can be achievedby quoting a large spread and granting price improvement totraders deemed uninformed. Consistent with our hypothesis wefind that price improvement reflects lower adverse selectioncosts but does not lead to a reduction in the specialist's profit.Further, the quote adjustment following transactions at thequoted bid or ask price is more pronounced than the quote adjustmentafter transactions at prices inside the spread. Our resultsindicate that anonymity comes at the cost of higher adverseselection risk. JEL Classification: G10.  相似文献   
46.
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   
47.
Using data from the Frankfurt Stock Exchange we analyze price formationand liquidity in a non-anonymous environment with similarities to thefloor of the NYSE. Our main hypothesis is that the non-anonymity allows the specialist to assess the probability that atrader trades on the basis of private information. He uses this knowledgeto price discriminate. This can be achieved by quoting a large spread and granting price improvement to traders deemed uninformed.Consistent with our hypothesis we find that price improvement reflects loweradverse selection costs but does not lead to a reduction in the specialist's profit. Further, the quote adjustmentfollowing transactions at the quoted bid or ask price is more pronounced than the quote adjustment aftertransactions at prices inside the spread. Our results indicate that anonymity comes at the cost ofhigher adverse selection risk.  相似文献   
48.
above the certainty level while for additive uncertainty the price should be lower than the certainty level. This note gives an intuitive explanation for the result after first presenting a parsimonious review of the two models. We also discuss which, if either, of the two models is more realistic. Received December 14, 2001; revised version received July 16, 2002 Published online: April 30, 2003 We thank referees for helpful comments. Ciaran Driver would like to acknowledge the research facilities from ANU, Canberra for their help in writing this paper.  相似文献   
49.
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   
50.
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   
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