基于排队论的销售模型分析

为降低企业销售时的综合成本,利用随机服务系统理论分析了顾客到达企业时的排队方式,得出单队多服务通道比多队多服务通道排队方式更优;分析了窗口之间相互帮助、同时为k个顾客服务、服务率可变、有多个顾客类以及是否需要雇佣帮手等多个服务模型,为企业选择适合自己的服务方式提供理论依据,并结合例题说明了选择恰当的服务方式能有效降低综合成本;还分析了库存容量对综合成本的影响,并得出最优库存容量.     

一类带有负顾客且具有反馈的M/G/1可修排队系统

研究了一类带有负顾客且具有反馈的M/G/1可修排队系统,正顾客服务完会以一定的概率立即排到队尾等待下一次服务,而以一定的补概率离开系统,永不再来。服务规则是先到先服务,负顾客抵消排队系统中的中间顾客（RCM）。使用“补充变量法”和状态转移方程分析该模型,得到了这一模型的排队指标和可靠性指标,并且发现此类排队系统完全取决于队长为2的概率。     

带有负顾客且具有反馈的M/G/1排队模型

将负顾客和反馈相结合研究了一类带有负顾客且具有反馈的M／G／1排队系统，正顾客服务完会以一定的概率立刻排到队尾等待下一次服务，以一定的概率离开系统，永不再来。这里考虑了负顾客的两种抵消情况，分别是负顾客抵消队列中的最后一个正顾客和负顾客抵消队首的正顾客，并分别给出了它们稳态存在的充分必要条件，利用补充变量法和状态转移分析模型，得到了它们的稳态队长的概率母函数。     

基于负顾客M/M/s/k＋M重试、反馈排队的呼叫中心性能分析

针对顾客到达时遇忙音重试、服务结束后以一定概率重新请求服务、顾客在排队中因不耐烦而放弃等待,以及负顾客等因素对系统产生的影响,研究了一类具有负顾客到达的,且顾客在ACD中排队中会因不耐烦而放弃等待的M/M/s/k＋M重试、反馈排队模型.运用矩阵几何方法求解,给出了解析解和系统的稳态性能指标,并给出数值计算实例以及适当提高服务率能降低总的顾客损失率等结论.     

具有二次服务、反馈、启动故障的M/G/1重试排队系统

考虑了一个具有二次服务、反馈和启动故障的M/G/1重试排队系统.在假定重试区域中只有队首的顾客允许重试的情况下,重试时间具有一般分布时,得到了系统稳态的充分必要条件.求得稳态时系统队长和重试区域中队长分布及相关指标.     

具有强占型优先权的不耐烦顾客的M/M/m/2k-m排队模型

首先给出了只有一类不耐烦顾客的M／M／m排队模型，其中顾客到达与服务都服从相互独立的泊松分布，顾客的耐心等待期限截止到服务开始前，并服从指数分布，最终得到了顾客丢失率及稳态下的队长分布。利用此结论研究了具有多个服务台，两类到达顾客的M／M／m/2k-m排队系统，其中第一类顾客对于第二类顾客具有强占型优先权，顾客的耐心等待时间即等待期限仍服从指数分布，两类顾客具有各自的等待轨道。采用矩阵分析的方法给出了两类顾客各自的稳态分布，并作了相应的性能分析。     

负顾客可服务的M/G/1休假排队系统

研究一类具有负顾客可服务的M/G/1休假排队系统,其中服务规则为后到先服务(LCFS),休假策略为空竭服务多重休假(ES,MV),负顾客也可以接受服务,正顾客也可以抵消负顾客,即正负顾客处在对等的位置上,抵消原则为抵消系统中正在接受服务的顾客(RCH).由补充变量法和状态转移方程的分析得到了稳态队长分布的广义概率母函数表达式.     

具有Bernoulli反馈的M/M/1工作休假排队系统

研究带反馈的M/M/1工作休假排队模型,这是一类新服务机制的工作休假排队系统.在休假期间,服务员并未完全停止工作,而是以相对于正常工作时较低的服务率为顾客服务.工作休假策略为空竭服务多重工作休假.完成服务的顾客以概率p（0SN 1671-1742     

具有负顾客的GI/M/1工作休假及休假中止模型

针对GI/M/1排队模型可能出现的影响因素,研究具有负顾客的GI/M/1工作休假及休假中止模型.其服务规则为先到先服务,休假策略为空竭服务多重休假,负顾客抵消队尾的正顾客。若休假期中一个服务完成时,系统中还有顾客,发生休假中止。通过矩阵几何解方法求得到达时刻队长的稳态分布.     

一类具有到达损失、第二次多选服务、反馈的M/G/1重试排队系统

考虑了一个具有到达损失、第二次多选服务、反馈和一般重试时间的M/G/1排队模型。假定重试区域中只有队首的顾客允许重试。重试时间具有一般分布时,得到了系统稳态的充分必要条件。使用补充变量法和状态转移方程分析该模型,求得稳态时系统队长和重试区域中队长分布及相关指标。     

Thermohaline structure inhomogeneity associated with polynia at the northern margin of Emery Ice-shelf

Based on the hydrographic data in austral summer during the 22nd Antarctic Expedition of China(2005/2006),some features can be found about the northern margin of Emery ice shelf as follows.The heat content in the surface layer(0-50 m) at the eastern end and the western end of the ice-shelf margin is much higher than that at the middle.The upper mixing-layer depth and the seasonal thermocline depth at the middle of the ice-shelf northern margin are much shallower than those at the both ends.However there is much less difference between the middle and the ends in the bottom layer.The remote sensing photos show that the inhomogeneity in the surface-layer water is closely related to the spatial distribution of the floes and polynia in the area.     

Phylogenetic analysis of cultivable bacteria isolated from Arctic sea-ice

Phylogenetic analysis based on 16S rDNA of 8 strains of cultivable bacteria isolated from Arctic sea-ice was studied.The results showed that strain BJ1 belonged to genus Planococcus,which was a genus of low mole percent G C gram-positive bacteria;strain BJ6 belonged to genus Burkholderia of β-proteobacteria and the rest 6 strain all belonged to γ-proteobacteria,of which strain BJ8 was a species of Pseudoalteromonas,strain BJ2-BJ5 and BJ7 were members of genus Psychrobacter.Phylogenetic analysis also indicated that bacteria of genus Psychrobacter of the isolates formed a relatively independent phylogenetic cluster in comparison with other bacteria belonged to genus Psychrobacter.     

Information for authors

正1 Aims and Scope Advances in Polar Science(APS)is an international,peer-reviewed journal jointly sponsored by the Polar Research Institute of China and the Chinese Arctic and Antarctic Administration.APS is a comprchensive academic journal dedicated to presentation of multi-disciplinary achievements in Arctic and Antarctic expeditions and research.Its primary purpose is to publish achievements in fundamental research,applied     

Advances in Polar Science CONTENTS(Volume 25,2014)

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Guide to Authors： Journal of Mountain Science

<正>AIMS AND SCOPE(Editorial Policy)The Journal of Mountain Science(JMS)is devoted to mountains and their surrounding lowlands-ecoregions of particular global importance,with a particular emphasis on the important highlands/mountains in the world,such as the Tibetan Plateau,the Himalayas,the Alps,the Andes,the Rockies and many other mountain ranges of our planet.     

Journal of Mountain Science(JMS)

<正>The Journal of Mountain Science(JMS),founded in2004,is an international English-language journal on mountain sciences.JMS is supervised by the Chinese Academy of Sciences(CAS),sponsored by the Chengdu Institute of Mountain Hazards and Environment,CAS,published by Science Press China,and distributed by Springer exclusively throughout the world(excluding Mainland China).The JMS is published bimonthly,fulltexted in SpringerLink and CNKI,indexed/abstracted by     

Preliminary study on plasma membrane fluidity of Psychrophilic Yeast Rhodotorula sp.NJ298 in low temperature

The ability of cell to modulate the fluidity of plasma membrane was crucial to the survival of microorganism at low temperature. Plasma membrane proteins, fatty acids and carotenoids profiles of Antarctic psychrophilc yeast Rhodotorula sp. NJ298 were investigated at -3 ℃, 0 ℃ and 8 ℃. The results showed that plasma membrane protein content was greater at -3 ℃ than that at 8 ℃, and a unique membrane polypeptide composition with an apparent molecular mass of 94.7 kDa was newly synthesized with SDS-PAGE analysis; GC analysis showed that the main changes of fatty acids were the percentage of unsaturated fatty acids (C18∶ 1 and C18∶ 2) and shorter chain saturated fatty acid (C10∶ 0) increased along with the decrease of the culture temperature from 8 ℃ to -3 ℃; HPLC analysis indicated that astaxanthin was the major functional carotenoids of the plasma membrane, percentage of which increased from 54.6±1.5% at 8 ℃ to 81.9±2.1% at -3 ℃. However the fluidity of plasma membrane which was determined by measuring fluorescence anisotropy was similar at -3 ℃, 0 ℃ and 8 ℃. Hence these changes in plasma membrane's characteristics were involved in the cellular cold-adaptation by which NJ298 could maintain normal plasma membrane fluidity at near-freezing temperature.     

Relationship of Arctic sea ice and Northern Hemispheric 500 hPa Polar vortices

Using the NCEP/NCAR reanalysis monthly 500 hPa height data on a 2.5 latitude-longitude grid and 1°×1° sea ice data,the polar vortex area,intensity index and arctic sea ice area index are calculated respectively,and the meridional distribution,period variation and the abrupts in the long range trend are analyzed to study their relationship.The results show that the meridional distribution of sea ice and polar vortex h-ave distinctive difference,the relative positions of them are different in the eastern and western hemispheres,and exept they have periods of 4 months,quasi half year,quasi year,4-5 years and 10 years commonly,and each of them has its own respective variation as well.The sea ice area is decreasing apparently since 1980's,so is the polar vortex area,but their abrupt changge time are different totally.The area of sea ice and polar vortex has prominent positive correlation,but the relationship of sea ice intensity,polar vortex intensity,polar vortex area is complicated.     

Author Index for Journal of Mountain Science Volume 11,2014,pp 1-1656

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