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In public health systems around the world, there are not enough medical resources to provide elective (e.g., scheduled or non-emergency) services for all patients immediately. One feasible solution is to prioritize patients by taking into account a variety of factors, such as disease severity, waiting time, and disease types. This is a typical Multiple Criteria Decision Making (MCDM) problem. To solve this problem, in this paper, we first conduct an investigation on the admission process, and obtain 16 indicators affecting patients’ admission, which form a criteria system. Since there is much vague and uncertain information which can be depicted by the hesitant fuzzy linguistic term set effectively for these indicators, we then apply a powerful MCDM method, named the hesitant fuzzy linguistic ORESTE, to prioritize the elective surgery patient admission in a Chinese public tertiary hospital, the West China Hospital. Robust results are obtained by performing a sensitivity analysis with six scenarios. We also compare the results with those derived by other HFL-MCDM methods. It is illustrated that the hesitant fuzzy linguistic ORESTE can help hospitals flexibly manage the patient admissions. 相似文献
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We consider a retrial queueing system with a single server and novel customer׳s admission discipline. The input flow is described by a Markov Arrival Process. If an arriving customer meets the server providing the service, it goes to the orbit and repeats attempts to get service in random time intervals whose duration has exponential distribution with parameter dependent on the customers number in orbit. Server operates as follows. After a service completion epoch, customers admission interval starts. Duration of this interval has phase type distribution. During this interval, primary customers and customers from the orbit are accepted to the pool of customers which will get service after the admission interval. Capacity of this pool is limited and after the moment when the pool becomes full before completion of admission interval all arriving customers move to the orbit. After completion of an admission interval, all customers in the pool are served simultaneously by the server during the time having phase type distribution depending on the customers number in the pool. Using results known for Asymptotically Quasi-Toeplitz Markov Chains, we derive stability condition of the system, compute the stationary distribution of the system states, derive formulas for the main performance measures and numerically show advantages of the considered customer׳s admission discipline (higher throughput, smaller average number of customers in the system, higher probability to get a service without visiting the orbit) in case of proper choice of the capacity of the pool and the admission period duration. 相似文献
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TD-LTE网络基于AoA+TA功能的接入控制应用 总被引:1,自引:1,他引:0
秦嗣仲 《电信工程技术与标准化》2015,(2):20-24
本文论述了在TD-LTE网络中遇见的新问题,即边境优化问题。中国移动TD-LTE网络建设与朝鲜隔江而建,参考丹东边境GSM网络的方法,结合TD-LTE网络自身特点,TD-LTE网络采用宏站小区覆盖朝鲜新义州沿江区域,令宏站小区采用基于位置的接纳控制算法(如Ao A+TA方法等),通过UE距离站点的远近限制朝鲜用户接入TD-LTE网络进行业务。 相似文献
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Xiaocheng Wang Qiaoni Han Xinping Guan Kai Ma 《International Journal of Communication Systems》2015,28(1):19-37
Femtocell technology has been drawing considerable attention as a cost‐effective means of improving cellular coverage and capacity. However, under co‐channel deployment, femtocell system in dense environment may incur high uplink interference to existing macrocells and experiences strong inter‐cell interference at the same time. To manage the uplink interference to macrocell, as well as the inter‐cell interference, this paper proposes a price‐based uplink interference management scheme for dense femtocell systems. Specifically, on the one hand, to guarantee the macrocell users' quality of service, the macrocell base station prices the interference from femtocell users (FUEs) subject to a maximum tolerable interference power constraint. On the other hand, the inter‐cell interference is also taken into consideration. Moreover, a Stackelberg game model is adopted to jointly study the utility maximization of the macrocell base station and FUEs. Then, in order to reduce the amount of information exchange, we design a distributed power allocation algorithm for FUEs. In addition, admission control is adopted to protect the active FUEs' performance. Numerical results show that the price‐based interference management scheme is effective. Meanwhile, it is shown that the distributed power allocation combined with admission control is capable of robustly protecting the performance of all the active FUEs. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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This paper investigates the improvement of the hospitalisation admission process of elective inpatients by delay announcement to free patients from blind and long wait, a phenomenon often observed in top Chinese hospitals. We propose a formal simulation model in which relevant resource requirements during the hospitalisation of a patient are represented by an original ‘multistage treatment model’. Other key components of the formal model include impatience of patients, resource capacities and key performance indicators such as the original concept of waiting time visibility. Through sensitivity analysis of the simulation model, we demonstrate the benefits of delay announcement and the value of our ‘multistage treatment model’. 相似文献
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Natalia Vassileva Yevgeni Koucheryavy 《Wireless Communications and Mobile Computing》2015,15(4):666-684
The adaptive modulation and coding (AMC) technique, which has been adopted by advanced mobile telecommunication systems, supports a flexible response to the random radio behaviour. As a result, the attained transmission rate over a wireless link is time varying. Hence, resource demands are not deterministic but fluctuating even for calls with constant bit rate service requirements. Consequently, constant bit rate calls are susceptible to a forced call termination because of insufficient resources not only in a target cell during inter‐cell handoffs but also in a serving cell during radio link deterioration. Furthermore, call blocking and dropping probabilities depend on radio propagation conditions among other factors and therefore they are dissimilar throughout a service area. The latter leads to unfairness problems. We analytically measure the impact of AMC on fixed‐rate service with hard delay constraints such as voice for different signal, mobility and traffic conditions. We consider a reference case (call requests are admitted into the system provided there are enough free resources) and two classes of admission control approaches: traditional (only inter‐cell handoffs are prioritised) and modified (all ongoing calls are prioritised). The reported results reveal conditions for which AMC affects voice call performance and can serve as guidelines on admission control design. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献