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Study on Ecological Footprint of Sightseeing Tourists and Vacation Tourists in Sanya City
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作者 邵小慧 罗艳菊 袁建平 《Journal of Landscape Research》 2010年第10期43-47,共5页
Based on the theory of ecological footprint and tourists' consumption structure, the model of tourist ecological footprint was divided into six sub-models including catering, accommodation, shopping, sightseeing, ... Based on the theory of ecological footprint and tourists' consumption structure, the model of tourist ecological footprint was divided into six sub-models including catering, accommodation, shopping, sightseeing, shopping and entertainment, and ecological footprint of sightseeing tourists and vacation tourists in Sanya City was analyzed. The result showed that per capita ecological footprint of vacation tourists was higher than that of sightseeing tourists in Sanya City. The influential factor of the two kinds of tourists was slightly different in their proportion of sightseeing and entertainment factors. In the future, it should advocate sightseeing tourists to rationally make use of ecological resources, vacation tourists to have a healthy and ecological holiday, so as to ensure sustainable development of tourism. 展开更多
关键词 SIGHTSEEING TOURISTS vacation TOURISTS ECOLOGICAL FOOTPRINT Sanya
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THE QUEUE-LENGTH DISTRIBUTION FOR M^x/G/1 QUEUE WITH SINGLE SERVER VACATION 被引量:2
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作者 唐应辉 唐小我 《Acta Mathematica Scientia》 SCIE CSCD 2000年第3期397-408,共12页
This paper studies the bulk-arrival M-x/G/1 queue with single server vacation. By introducing the server busy period and using the Laplace transform, the recursion expression of the Laplace transform of the transient ... This paper studies the bulk-arrival M-x/G/1 queue with single server vacation. By introducing the server busy period and using the Laplace transform, the recursion expression of the Laplace transform of the transient queue-length distribution is derived. Furthermore, the distribution and stochastic decomposition result of the queue length at a random point in equilibrium are obtained. Especially some results for the single-arrival M/G/1 queue with single server vacation and bulk-arrival M-x/G/1 queue but with no server vacation can be derived directly by the results obtained in this paper. 展开更多
关键词 server vacation queue length transient distribution equilibrium distribution stochastic decomposition
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THE TRANSIENT SOLUTION FOR M/G/1 QUEUEWITH SERVER VACATIONS 被引量:13
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作者 唐应辉 《Acta Mathematica Scientia》 SCIE CSCD 1997年第3期276-282,共7页
In this paper, the transient solutions for M/G/1 queues with single server vacation and multiple server vacations are firstly studied, and the recursion expressions of their Laplace transform are given. Further the di... In this paper, the transient solutions for M/G/1 queues with single server vacation and multiple server vacations are firstly studied, and the recursion expressions of their Laplace transform are given. Further the distribution and stochastic decomposition result of the queue length at a random point in equilibrium are directly obtained from the transient solution. As will be seen this paper provides a intuitive and elegant method for studying transient solutions for M/G/1 queues with single server. 展开更多
关键词 server-vacation queue length transient solution stochastic decomposition
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M/G/1 Vacation Queueing Systems with Server Timeout 被引量:2
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作者 Oliver C. Ibe 《American Journal of Operations Research》 2015年第2期77-88,共12页
We consider a single-server vacation queueing system that operates in the following manner. When the server returns from a vacation, it observes the following rule. If there is at least one customer in the system, the... We consider a single-server vacation queueing system that operates in the following manner. When the server returns from a vacation, it observes the following rule. If there is at least one customer in the system, the server commences service and serves exhaustively before taking another vacation. If the server finds the system empty, it waits a fixed time c. At the expiration of this time, the server commences another vacation if no customer has arrived;otherwise, it serves exhaustively before commencing another vacation. Analytical results are derived for the mean waiting time in the system. The timeout scheme is shown to be a generalized scheme of which both the single vacation and multiple vacations schemes are special cases, with c=&infin;and c=0, respectively. The model is extended to the N-policy vacation queueing system. 展开更多
关键词 vacation QUEUEING Systems TIMEOUT POLICIES Performance Analysis N-POLICY with TIMEOUT
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Effects of Reneging, Server Breakdowns and Vacation on a Batch Arrival Single Server Queueing System with Three Fluctuating Modes of Service 被引量:1
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作者 Samuel Ugochukwu Enogwe H. Onyebuchi Obiora-Ilouno 《Open Journal of Optimization》 2020年第4期105-128,共24页
This article examines the effects of reneging, server breakdown and server vacation on the various states of the batch arrivals queueing system with single server providing service to customers in three fluctuating mo... This article examines the effects of reneging, server breakdown and server vacation on the various states of the batch arrivals queueing system with single server providing service to customers in three fluctuating modes. In this queueing system, any batch arrival joins the queue if the server is busy or on vacation or under repair. However, if the server is free, one customer from the arriving batch joins the service immediately while others join the queue. In case of server breakdown, the customer whose service is interrupted returns back to the head of the queue. As soon as the server has is repaired, the server attends to the customer in mode 1. For this queueing system, customers that are impatient due to breakdown and server vacation may renege (leave the queue without getting service). Due to fluctuating modes of service delivery, the system may provide service with complete or reduced efficiency. Consequently, we construct the mathematical model and derive the probability generating functions of the steady state probabilities of several states of the system including the steady state queue size distribution. Further, we discuss some particular cases of the proposed queueing model. We present numerical examples in order to demonstrate the effects of server vacation and reneging on the various states of the system. The study revealed that an increase in reneging and a decrease in server vacation results in a decrease in server utilization and an increase in server’s idle time provided rates of server breakdown and repair completion are constant. In addition, the probability of server vacation, the probability of system is under repair and the probabilities that the server provides service in three fluctuating modes decreases due to an increase in reneging and a decrease in vacation completion rates. 展开更多
关键词 QUEUEING RENEGING Server vacation Server Breakdowns Fluctuating Modes of Service
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The M<sup>X</sup>/M/1 Queue with Multiple Working Vacation 被引量:2
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作者 Yutaka Baba 《American Journal of Operations Research》 2012年第2期217-224,共8页
We study a batch arrival MX/M/1 queue with multiple working vacation. The server serves customers at a lower rate rather than completely stopping service during the service period. Using a quasi upper triangular trans... We study a batch arrival MX/M/1 queue with multiple working vacation. The server serves customers at a lower rate rather than completely stopping service during the service period. Using a quasi upper triangular transition probability matrix of two-dimensional Markov chain and matrix analytic method, the probability generating function (PGF) of the stationary system length distribution is obtained, from which we obtain the stochastic decomposition structure of system length which indicates the relationship with that of the MX/M/1 queue without vacation. Some performance indices are derived by using the PGF of the stationary system length distribution. It is important that we obtain the Laplace Stieltjes transform (LST) of the stationary waiting time distribution. Further, we obtain the mean system length and the mean waiting time. Finally, numerical results for some special cases are presented to show the effects of system parameters. 展开更多
关键词 MX/M/1 QUEUE MULTIPLE Working vacation Probability Generating Function WAITING Time Distribution Stochastic Decomposition
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The M//M//1 Queue with Controlled Multiple Working Vacations
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作者 ZHANG Hong-bo FENG Ping-hua 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第2期159-165,共7页
In this paper, we study an M/M/1 queue with multiple working vacations under following Bernoulli control policy: at the instants of the completion of a service in vacation, the server will interrupt the vacation and e... In this paper, we study an M/M/1 queue with multiple working vacations under following Bernoulli control policy: at the instants of the completion of a service in vacation, the server will interrupt the vacation and enter regular busy period with probability 1 p (if there are customers in the queue) or continue the vacation with probability p. For this model, we drive the analytic expression of the stationary queue length and demonstrate stochastic decomposition structures of the stationary queue length and waiting time, also we obtain the additional queue length and the additional delay of this model. The results we got agree with the corresponding results for working vacation model with or without vacation interruption if we set p = 0 or p = 1, respectively. 展开更多
关键词 M/M/1 queue working vacation Bernoulli policy vacation interruption stochastic decomposition
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A Non-Preemptive Priority Queueing System with a Single Server Serving Two Queues M/G/1 and M/D/1 with Optional Server Vacations Based on Exhaustive Service of the Priority Units
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作者 Kailash C. Madan 《Applied Mathematics》 2011年第6期791-799,共9页
We study a vacation queueing system with a single server simultaneously dealing with an M/G/1 and an M/D/1 queue. Two classes of units, priority and non-priority, arrive at the system in two independent Poisson stream... We study a vacation queueing system with a single server simultaneously dealing with an M/G/1 and an M/D/1 queue. Two classes of units, priority and non-priority, arrive at the system in two independent Poisson streams. Under a non-preemptive priority rule, the server provides a general service to the priority units and a deterministic service to the non-priority units. We further assume that the server may take a vacation of random length just after serving the last priority unit present in the system. We obtain steady state queue size distribution at a random epoch. Corresponding results for some special cases, including the known results of the M/G/1 and the M/D/1 queues, have been derived. 展开更多
关键词 Non PREEMPTIVE PRIORITY QUEUEING SYSTEM Modified Server vacations Combination of General SERVICE and Deterministic SERVICE Steady State Queue Size Distribution
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Assessment on the component pattern of mountain vacation potential suitability in Hunan Province, China
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作者 DU Ting-ting LI Da-li ZHONG Yong-de 《Journal of Mountain Science》 SCIE CSCD 2022年第3期892-908,共17页
In China,mountain destinations offer more opportunities for vacation than beaches and springs,with a larger national coverage,richer landscapes and various diverse folk cultures.Hunan Province,for example,serves as a ... In China,mountain destinations offer more opportunities for vacation than beaches and springs,with a larger national coverage,richer landscapes and various diverse folk cultures.Hunan Province,for example,serves as a typical mountain tourism destination.Our research aims to assess the potential suitability and component pattern of holidaymaking in Hunan Province to support for scientific endeavors and sustainable use of mountain resources in Hunan.An approach for mapping potential suitability was constructed based on Weighted Linear Combination(WLC)of six primary factors including terrain,climate suitability period,biology and environment,human activity culture,hydrological landscape,and road infrastructure,which is calculated on the base of eleven secondary factors used as suitability criteria.Analytic hierarchy process(AHP)and geographic information system(GIS)were also integrated into the evaluation models to prepare six single and complex factor suitability maps for mountain vacation.Multivariate clustering was used to clarify the component pattern of single factor combinations in each mountain vacation suitability index(MVSI)class.The results have shown that:1)Regions with high suitability are distributed with characteristics of significant dispersion and limited aggregation;2)15.89%of the sample mountains are highly suitable,30.78%are moderately suitable,42.61%are marginally suitable and 10.72%are poorly suitable;3)The complexity of index combination corresponding to each level is different;4)Different combinations emphasize different destination needs.The study reveals the suitability class,characteristics,and limiting factors of mountain vacation in different geographical locations on the provincial scale.These elements play an instructive role in scientific decision-making and orderly exploitation of resources among Hunan’s Mountain destinations.Furthermore,the study can also be used as a basis for the suitability evaluation of mountain vacation in other areas. 展开更多
关键词 Mountain vacation Suitability evaluation Component pattern Analytic hierarchy process Geographic information system Hunan Province
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Development Strategies of Rural Vacation in Puqian Town, Heyuan City
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作者 CHEN Haiming LIAO Zimeng 《Journal of Landscape Research》 2022年第6期107-110,共4页
Puqian Town, Heyuan City has beautiful natural environment and agricultural landscape and unique hot spring resources, so it is very suitable for the development of rural vacation industry. At present, there were only... Puqian Town, Heyuan City has beautiful natural environment and agricultural landscape and unique hot spring resources, so it is very suitable for the development of rural vacation industry. At present, there were only two vacation projects of Bavaria Manor and Ketianxia Hot Spring Resort in the town, and the radiation driving effect is not obvious. In this paper, literature research and interview methods were used to collect data. After 15 interviewees were effectively interviewed and hundreds of data were collected, the PEST theory model and balanced points card theory were used to measure the development factors of rural vacation in Puqian Town, Heyuan City. SWOT matrix matching analysis method was adopted to determine the development strategies of local rural vacation industry. 展开更多
关键词 Rural vacation Rural revitalization Puqian Town Heyuan
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Group Travel to China, Take Two: the Family Vacation
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作者 MARY ANNE SEDNEY 《China Today》 2001年第3期70-71,共2页
关键词 the Family vacation Take Two Group Travel to China
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Machine Interference Problem with Reliable Server under Single Vacation
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作者 Ojobor, S. A. 《Journal of Mathematics and System Science》 2014年第11期732-742,共11页
The machine interference problem with reliable server under single vacation is considered here. There are M similar machines that are subject to fail or breaks down with a single server who is responsible for repairin... The machine interference problem with reliable server under single vacation is considered here. There are M similar machines that are subject to fail or breaks down with a single server who is responsible for repairing or maintaining the failed machines. The machine fails completely at random with rate 2 and they are serviced in order of breaks down. More so, the machines operate independently but are subject to fail or break down. The service time distributions of the failed machines are assumed to be exponentially distributed with state dependent service rate #n, where n is the number of failed machines. By state dependent service rate we mean a situation where the rate of service depends on the number of failed machines present in the system. The Chapman-Kolmogorov differential equations obtained for the reliable server under single vacation model is solved through ODE45 (Runge-Kutta algorithm of order 4 and 5) in MATLAB programming language. The transient probabilities obtained are used to compute the operational measures of performance for the systems. The following time dependent operational measures of performance for the system are obtained: expected number of failed machines, expected number of operating machines, machine availability, expected idle period, expected busy period, operational utilization of the machine, the variance of the expected number of failed machine and variance of expected number of operating machine in the system. The effects of failure rate of machines, service rate of failed machines and the number of operating machines are investigated; it is observe that the rate at which machine fails and is serviced, affect the expected number of failed and operating machines in the system. The CPU time for obtaining the transient results for the systems and the variance of the systems are reported in this work. 展开更多
关键词 Transient solution machine interference problem Reliable server Single vacation ODE45 in MATLAB.
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An M/G/1 Retrial Queue with Exhaustive Service and Server Vacations
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作者 Mohamed Boualem Natalia Djellab Djamil Aissani 《通讯和计算机(中英文版)》 2011年第9期720-726,共7页
关键词 M/G/1 服务器 队列 休假 嵌入马尔可夫链 性能分析 稳态分布 系统
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My Summer Vacation Plan
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作者 费依婷 叶婧(指导) 《疯狂英语(双语世界)》 2019年第2期84-85,共2页
I have a summer vacation plan.I’m going to the USA with my family.Because it’s very far from Zhongshan,I’m going to America by plane.First, I’d like to go to Washington D.C.There, I will be able to see the White H... I have a summer vacation plan.I’m going to the USA with my family.Because it’s very far from Zhongshan,I’m going to America by plane.First, I’d like to go to Washington D.C.There, I will be able to see the White House.It’s said that it is very beautiful.But I only saw it on TV or in the newspapers or on the magazines before.When I get there, I’ll take some nice photos.When I come back to Zhongshan, I’ll share them with my classmates. 展开更多
关键词 MY SUMMER vacation PLAN
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A Meaningful Summer Vacation
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作者 陈潇潇 《中学生英语》 2019年第35期6-6,共1页
Meaningful Summer Vacation I'll be a senior high school student after this summer vacation, so my parents and I decided making①this summer vacation a special and memorable one for me.
关键词 Meaningful SUMMER vacation PARENTS
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VACATION
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作者 Doris Brougham Johnny Wen(Music) 《空中英语教室(初级版.大家说英语)》 2010年第6期7-7,共1页
关键词 英语学习 学习方法 阅读 翻译 vacation
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My Vacation
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作者 王锋 《中学生英语(初中版)》 2008年第35期18-18,共1页
旨在提高英语写作水平,互相交流,取长补短,我们开辟了"学生习作名师点评"栏目。如果你想看看自己的写作水平如何,请将习作邮寄给我们,我们会将其转交给省内各校名师点评;老师们如果想推荐自己学生的优秀习作,请按栏目要求邮... 旨在提高英语写作水平,互相交流,取长补短,我们开辟了"学生习作名师点评"栏目。如果你想看看自己的写作水平如何,请将习作邮寄给我们,我们会将其转交给省内各校名师点评;老师们如果想推荐自己学生的优秀习作,请按栏目要求邮寄给我们。 展开更多
关键词 学生习作 书面表达 My vacation
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Lesson 4:Where Will You Spend Your Vacation?
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《China Today》 2007年第4期80-81,共2页
关键词 Lesson 4:Where Will You Spend Your vacation
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重庆市大学生暑期饮酒模式及其相关因素研究
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作者 杨健 程聪 +3 位作者 胡倩 肖磊 赵勇 张帆 《现代医药卫生》 2024年第13期2266-2271,共6页
目的分析重庆市大学生暑假期间的饮酒模式和主要影响因素,为进行针对性健康生活方式干预提供一定理论依据。方法采用分层整群抽样的方法,招募到487名大学生,对其中420名饮酒者进行暑期饮酒行为调查。使用频数和百分比进行一般描述,百分... 目的分析重庆市大学生暑假期间的饮酒模式和主要影响因素,为进行针对性健康生活方式干预提供一定理论依据。方法采用分层整群抽样的方法,招募到487名大学生,对其中420名饮酒者进行暑期饮酒行为调查。使用频数和百分比进行一般描述,百分率的比较采用χ^(2)检验。使用单因素和多因素二元逻辑回归分析重庆市大学生暑期饮酒的主要影响因素。结果487名大学生中,饮酒率为86.24%(420/487),暑期饮酒率为29.57%(144/487),暑期饮酒量为4(4.0~16.5)标准杯。暑期饮酒者中91.67%(132/144)饮啤酒,56.25%(81/144)在餐馆饮酒。性别[调整比值比(AOR)=4.659,95%可信区间(95%CI)2.998~7.238]、父亲和母亲的饮酒行为(AOR=1.934,95%CI 1.151~3.251;AOR=2.341,95%CI 1.403~3.907)是大学生暑期饮酒行为的影响因素。结论重庆市大学生暑期饮酒较普遍,是健康一级预防的潜在风险点。在进行暑期饮酒一级预防时应重点关注女性和父母不饮酒的大学生。 展开更多
关键词 大学生 健康生活 饮酒行为 暑假 一级预防 重庆
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基于启动时间和完全故障的双阶段休假排队系统的流体模型性能分析
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作者 徐秀丽 张怡通 +1 位作者 王勋 刘洺辛 《数学物理学报(A辑)》 CSCD 北大核心 2024年第4期1092-1109,共18页
基于风力发电路灯的能量转化机制,该文构建并分析了具有启动时间和完全故障策略的M/M/1排队系统驱动的流体模型.首先,对驱动系统进行模型描述,运用矩阵几何解方法得到驱动系统的稳态概率分布.其次,引入流体模型的净输入率结构,并利用概... 基于风力发电路灯的能量转化机制,该文构建并分析了具有启动时间和完全故障策略的M/M/1排队系统驱动的流体模型.首先,对驱动系统进行模型描述,运用矩阵几何解方法得到驱动系统的稳态概率分布.其次,引入流体模型的净输入率结构,并利用概率分析方法得到流体库存水平在稳态条件下的微分差分方程组,进而运用Laplace-Stieltjes transform(LST)方法得到稳态条件下库存量的均值及空库概率.根据性能指标构建系统的费用函数,在数值分析中给出系统参数对性能指标和费用的影响. 展开更多
关键词 流体模型 双阶段休假 启动时间 完全故障 库存量
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