• The Journal of Korean Institute of Communications and Information Sciences
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• v.12 no.2
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• pp.92-101
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• 1987

Messages which are entered into communication networks are processed according to the priorities manipulated by serveral queueing disciplines. This study is concerned with one of those disciplines, dynamic priority. We analyzed the everage waiting time for the messages be processed by dynamic priority in queue. The priority is variated by the message's waiting time in queue. The dynamic priority discipline can be classified according as messaged have initial priority or not. Difference of above two discriplines were considered.

• Journal of Communications and Networks
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• v.9 no.3
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• pp.229-235
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• 2007

This paper analyzes the performance of a Bluetooth piconet in error-prone environments. A statistical characterization of a waiting time, an end-to-end delay, and a goodput are derived analytically in terms of the arrival rates, the number of slaves, and the packet error rate (PER). For simplicity, half-symmetric piconet is assumed in this analysis. Both exhaustive and limited scheduling are considered. The analytic results are validated by simulations.

• The Transactions of the Korea Information Processing Society
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• v.6 no.10
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• pp.2790-2796
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• 1999

In video-on-demand systems, the I.O bandwidth of video servers is the critical resource which contributes to increase in latency. Several approaches: bridging, piggybacking are used to reduce the I/O demand on the video server through sharing. Batching delays the requests for the different videos for a batching window so that more requests for the same video arriving during the current batching window may be served using the same stream. In this paper, we propose an adaptive reservation-based batching policy which dynamically reserves video server capacity for popoular videos according to video server loads. The performance of the proposed policy is evaluated through a simulation, and is compared with simple batching and static reservation-based batching policies. As the result, we know that the adaptive reservation-based batching policy more improves service ratio and average waiting time than simple batching and simple reservation-based batching policy more improves service ratio and average waiting time than simple batching and simple reservation-based batching polices.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.2
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• pp.53-57
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• 2006

Radionuclide therapy has been used for more than 50 years and proved to be a safe and effective modality. However, the patients' right to have the excellent medical service is seriously disturbed by excessive regulations of government institutions such as Korea Institute of Nuclear Safety (KINS), Health Insurance Review Agency (HIRA) and Korea Food and Drug Administration (KFDA). For example, the patients should wait for more than 6 months to have I-131 treatment in many hospitals it is strongly recommended to mitigate the regulations to resonable levels to solve the problems. If HIRA allow the hospitals to charge reasonable rate for radionuclide therapy room, then more hospitals would invest to build the radionuclide therapy rooms and the patients' waiting time would decrease. The waiting time would also decrease, if KINS allow 2 patients to share a radionuclide therapy room. Finally, it is strongly recommended to lower the threshold for approval of new therapeutic radiopharmaceuticals by KFDA, which would allow new effective therapeutic raoiopharmaceuticals to be introduced to clinical practices more easily.

• Child Health Nursing Research
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• v.14 no.1
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• pp.5-13
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• 2008

Purpose: This study was done to describe utilization status of emergency medical service for children at one university affiliated hospital located in Seoul. Data were obtained from the medical records of patients under 13 years of age who visited the ER from January 1 to December 31, 2006. Method: Medical records missing the time of discharge were excluded in the analysis of waiting time, which resulted in 19,766 cases. Data were analyzed using SPSS WIN 14.0 version. Result: There were slightly more boys (58.4%), average age of the children was 3.97 years of age. More children at the aged 1 to 3 years (51.3%) visited the ER. Fever was the most frequent complaint: 5,180 cases (24.38%). The other complaints were head or facial laceration (10.55%), vomiting (9.63%), abdominal pain (8.06%), cough (7.67%), and painful limb swelling (6.34%). Average waiting time before the first medical examination was 17 minutes, and average ER stay time was 3 hours and 23 minutes. Conclusion: The results suggest the need to assign a nurse specialist for pediatric ER to provide more efficient care for the children. Also, extra staff assignment during the evening shift or extending office hours of local pediatricians should be considered.

• Journal of the Korean Institute of Intelligent Systems
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• v.13 no.1
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• pp.76-84
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• 2003

Now days, It is based on GIS and GPS, it can search for the shortest path and estimation of arrival time by using the internet and cell phone to driver. But, even though good car navigation system does not create which is the shortest path when there average vehicle speed is 10 -20 Km. Therefore In order to reduce vehicle waiting time and average vehicle speed, we suggest optimal green time algorithm using fuzzy adaptive control, where there are different traffic intersection length and lane. In this paper, it will be able to forecast the optimal traffic information, estimation of destination arrival time, under construction road, and dangerous road using internet.

• The Bulletin of The Korean Astronomical Society
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• v.28 no.2
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• pp.37-37
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• 2003

• Journal of the Korean Operations Research and Management Science Society
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• v.19 no.3
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• pp.235-241
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• 1994

We consider a B/G/1 queueing with vacations, where the server closes the gate when it begins a vacation. In this system, customers arrive according to a Bernoulli process. The service time and the vacation time follow discrete distributions. We obtain the distribution of the number of customers at a random point in time, and in turn, the distribution of the residence time (queueing time + service time) for a customer. It is observed that solutions for our discret time B/G/1 gated vacation model are analogous to those for the continuous time M/G/1 gated vacation model.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38B no.2
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• pp.97-104
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• 2013

This paper introduces waiting time based periodic packet discard policy for frame based scheduler. This policy can be used with conventional packet discard policy or buffer management schemes, such as drop-tail or random early detection. Proposed discard policy discards packets, which are stayed in the buffer longer than threshold, at every period of scheduling. This decision of discard is based on waiting time of packet. In this paper, mathematical analysis is performed with situation of network congestion. Also, the simulation is performed to evaluate the performance of proposed discard policy. In the result, proposed discard policy can limit queuing delay by threshold. Also, if the packet discard is performed before scheduling and threshold is set with smaller value than frame length, it can limit the throughput of traffic.

• Journal of the Korean Society of Food Culture
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• v.26 no.4
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• pp.344-353
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• 2011

The objective of this study was to classify dining-out customers' behaviors at ski resorts based on their restaurant selection factors. Data were collected one-on-one via interview questionnaires of 178 customers at the ski resorts. The mean scores of important attributes (4.12) and satisfactory attributes (3.08) for the sport&leisure purpose group were analyzed. For the date&family trip purpose group, the important attributes (4.13) and satisfactory attributes (3.06) were evaluated, resulting in a significant difference between the two visiting-purpose groups by independent t-test (p<0.05). The recognized important attributes for the sport&leisure purpose group were food taste (4.54), hygiene (4.53), menu variety (4.22), menu price (4.15), and convenience (4.12), and the most recognizable satisfactory attributes were related to convenience (3.52), waiting time (3.95), and employee service (3.90). For the date&family trip purpose group, recognized important attributes were hygiene (4.83), food taste (4.67), menu price (4.40), convenient (4.33), menu variety (4.25), waiting time (4.21), and employee service (4.10), and marked satisfactory attributes were convenience (3.65), hygiene (3.31), atmosphere (3.25), employee service (3.23), waiting time (3.17), and food taste (3.00). These results suggest that restaurant selection attributes would be useful tools to restaurant managers in controlling the quality of foodservice and satisfying service requirements for dinning-out customers at ski resorts.