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51.
This paper deals with a single server Poisson arrival queue with two phases of heterogeneous service along with a Bernoulli schedule vacation model, where after two successive phases service the server either goes for a vacation with probability p (0≤p≤1) or may continue to serve the next unit, if any, with probability q(=1−p). Further the concept of multiple vacation policy is also introduced here. We obtained the queue size distributions at a departure epoch and at a random epoch, Laplace Stieltjes Transform of the waiting time distribution and busy period distribution along with some mean performance measures. Finally we discuss some statistical inference related issues. 相似文献
52.
欧共体竞争法的实施机制及对我国的启示 总被引:3,自引:0,他引:3
许光耀 《湘潭大学学报(哲学社会科学版)》2006,30(1):51-58
欧盟理事会第1/2003号条例取代了1962年第17号条例,废除了原有的事前申报制度,实现了欧共体竞争法实施的非集权化,加强了欧盟委员会的调查权,由此确立了“非集权”的竞争法实施机制①。在新机制下,委员会负责制定和发展欧共体的竞争政策,实施欧共体竞争法的任务由各成员国承担。作为世界上最先进的竞争法体系之一,欧共体竞争法的最新发展对我国竞争法制的确立有重要的借鉴意义。 相似文献
53.
目的研究脑的SPECT显像在鉴别诊断帕金森病与血管性帕金森综合征中的作用。方法10例血管性帕金森综合征患者、20例帕金森病患者与16例健康对照者。口服复方碘溶液后30min,从患者的肘正中静脉注射放射性活度为1110MBq的99mTC TRODAT1,2h后完成图象采集,后24h之内由SPECT中心进行图象分析。感兴趣区域(ROI,regions of interes)包括纹状体区:左右侧壳核及左右侧尾状核。对比区域用跟侧小脑皮质区域,并进行半定量分析,确定每一位检查者的感兴趣区域与小脑的比值。结果将SPECT/CT同机融合脑成像及同机脑CT采集,经COSEM重建后得到SPECT脑横断、冠状、矢状面的三维图像。并与CT进行同机图像融合,观察多巴胺神经元较为集中的区域即双侧纹状体区(尾状核、壳核)放射性分布。健康对照者,在纹状体的任何区域无论是壳核还是尾状核,都没有明显的多巴胺转运蛋白扫描的减低。血管性帕金森综合征患者壳核和尾状核均有轻度减低,但无论是壳核还是尾状核的减低同健康对照者相比,均无统计学意义。但是帕金森病毒者的纹状体区域特别是壳核显示出明显的99mTcTRODAT1摄取量的下降,既多巴胺转运蛋白的扫描的减低。PD组与对照组壳核与尾状核的摄取比值均有明显差别(P<0·01),PD组患者的壳核比尾状核的多巴胺放射性减低明显。对于每一位PD患者双侧的差别进行配对t检验,说明PD患者的SPECT半定量分析多以发病侧肢体的对侧纹状体减低明显。结论99mTc TRODAT1与多巴胺转运蛋白有较高的亲和力,且有较高的特异性与选择性。99mTc TRODAT1SPECT/CT同机融合脑成像是鉴别血管性帕金森综合征与帕金森病患者的较为适用的方法。 相似文献
54.
宋阳成 《吉林工程技术师范学院学报》2005,(12)
根据食品罐藏原理,研究糖水山竹罐头的生产工艺,主要介绍以成熟山竹为原料,制成营养丰富、风味独特、质量达到标准的山竹罐头的加工工艺。 相似文献
55.
Sherman Hanna Sharon DeVaney Allen Martin 《Journal of Family and Economic Issues》1996,17(3-4):297-311
A computer simulation game designed to give students insights into family time use concepts has been used in an introductory family resource management class at Ohio State University and other universities. The game allows for planning for time use changes over the family life cycle. The game can give students insights into economic and sociological models of time use. It is possible that future versions of the game could be used in family counseling.His research interests include derivation of optimal decision-making rules for families and family financial management.Her research interests include financial management over the life course including financial ratios, baby boomers, and retirement. She received her Ph.D. in 1993 from The Ohio State University in Family Resource Management.His research interests include the time trade-offs made between couples, financial planning over the life cycle, and the interaction of time and money between families and their home-based businesses. He received his Ph.D. in 1993 from The Ohio State University in Family Resource Management. 相似文献
56.
本文应用生成坐标方法(GCM)给出了相互作用玻色子模型(IBM)的连续变量表示,统一地处理了球形核和形变核的情形,并对轴对称形变核作出其连续变量表示的数值计算,其结果与IBM代数解(PHINT程序)是一致的. 相似文献
57.
C. L. Sheng 《Theory and Decision》1989,26(2):175-195
This paper clarifies and interprets some basic quantitative concepts of value, utility and utility function from a utilitarian point of view. First, I discuss the question as to whether value is objective or subjective. I hold that value is subjective and statistical in nature (although from the various subjective values of a certain object a norm can usually be obtained). Second, I emphasize the distinction between use value and exchange value in relation to utility. Third, I propose a law of diminishing incremental interest, which refers to the incremental (marginal) utility of money. Fourth, I identify the utility of money with the von Neumann-Morgenstern utility. Fifth, I question the necessity of the usual normalization of utility functions and the restricted linear transformation (and the consequent concept of strategic equivalence). Sixth, I discuss in detail the terminal values and utilities of a utility function from a philosophical rather than mathematical point of view, particularly the boundedness of a utility function and the magnitudes of V
0 and U
0. Finally, I conclude that, in order to be able to have interpersonal comparisons of utility, utility should have the same dimension as value rather than no dimension, and the normalization problem should be reconsidered in the light of terminal values and utilities. 相似文献
58.
张凇纶 《浙江大学学报(人文社会科学版)》2022,52(1):82-93
尽管具有一定保障性,但宅基地制度的首要目标在于经济管理,其表面上强调“户有所居”,实际是“户有定居”。宅基地上使用权所承载的管理性与农民自费建造农房所有权的私权性,存在内在的矛盾,不应适用房地一体规则,因为后者遵循着传统民法应对市场交易的基本逻辑。自然资源部所发布的文件明确了宅基地使用权可以由城镇居民继承,内核乃是基于房地一体,以房屋所有权的可继承带动宅基地使用权的可继承,颇为冒进。宅基地上所有权与房屋使用权应当分离,这将为宅基地的流转与乡村振兴提供新的契机:农房的自由流转加上宅基地使用权的农民保有,将最大限度地在现有阶段实现市场与制度的有机契合;对于取得农房的所有权人,在房地分离之下,可以借助对宅基地使用权的法定租赁来设计合理的权利结构。 相似文献
59.
This paper develops a model ofinter vivos gifts and bequests in a setting of moral hazard and adverse selection. Altruistic parents do not perfectly know how much effort their children make to earn their living, nor do they know their true level of ability.Inter vivos gifts take place prior to the realization of the children's earnings whereas at the moment of bequests, parents do observe them. We show that an optimal transfer policy generally uses a mix ofinter vivos gifts — deemed as more efficient — and bequests — deemed as more redistributive.We are thankful to Allessandro Cigno, Jacques Cremer, Claude d Aspremont and anonymous referees for their comments.Responsible editor: Alessandro Cigno 相似文献
60.
Summary We consider a lotL formed byN apparently similar unitsW
1,…,W
N, where each of theW
i may come from one of two different populationsP
1 andP
2;T
1,…,T
N denote the corresponding lifetimes. The units fromP
i
undergo a failure of kindi and their survival function isS
i
(t).
We assume that the failure rate function
are known and that the units fromP
1 are ?substandard?: λ
1
(t)≥λ
2
(t), ∀t≥0.
We want to putW
1,…,W
N under a pre-operational test (burn-in test) in order to eliminate at least a great part of the substandard units and we face
the problem of obtaining a rule for stopping the test under the assumption that, with the failure of a unit, it is possible
to recognize the population from which the unit comes.
Such a problem will be formalized as an optimal stopping problem for a suitably defined Markov process. Our study shall evidentiate
some fundamental aspects of the problem and the role of the prior distribution of the (random) numberM
0 of those units inL coming fromP
1 (substandard). The latter distribution has a great influence on the form of the solution.
This research was supported by the C.N.R. Project ?Statistica Bayesiana e Simulazione in Affidalità e Modellistica Biologica?. 相似文献