http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
MinJeong Kim,SungGon Kim,HyoJeong Kim,HoChan Kim,JiHeh Park,KwangSeok Park,DukKi Lee,WonTan Byun,CheolMin Kim 대한신경정신의학회 2008 PSYCHIATRY INVESTIGATION Vol.5 No.3
Objective-The Penn Alcohol Craving Scale (PACS) is a stronger predictor of subsequent drinking and relapse of alcohol dependence that can be administered more quickly and easily than other craving scales. The goal of this study was to develop the Korean version of the Penn Alcohol Craving Scale (PACS-K). Methods-To examine the psychometric properties of the PACS-K, responses were chosen from 80 patients admitted to a treatment facility for alcohol dependence. Results-The PACS-K possesses good psychometric properties, as assessed by Cronbach’s α estimates (Cronbach’s α=0.91). The test-retest reliability of the PACS-K showed high correlation (p<0.01) when the retest interval was 1 day. When the validity of the PACS-K was investigated using correlation analysis with two other craving scales (the Obsessive Compulsive Drinking Scale (OCDS) and the Visual Analogue Scale (VAS), high correlations were obtained between total PACS scores and total OCDS scores, and between total PACS scores and VAS scores (p<0.01, respectively). Conclusion-The PACS-K is a reliable and valid measure of alcohol cravings, and it could be useful for predicting which individuals are at risk for subsequent relapse.
Kim, Sunggon The Korean Statistical Society 2018 Communications for statistical applications and me Vol.25 No.4
$P^M_{\lambda}$-service policy is a workload dependent hysteretic policy. The policy has two service states comprised of the ordinary stage and the fast stage. An ordinary service stage is initiated by the arrival of a customer in an idle state. When the workload of the server surpasses threshold ${\lambda}$, the ordinary service stage changes to the fast service state, and it continues until the system is empty. These service stages alternate in this manner. When the cost of changing service stages is high, the hysteretic policy is more efficient than the threshold policy, where a service stage changes immediately into the other service stage at either case of the workload's surpassing or crossing down a threshold. $P^M_{\lambda}$-service policy is a modification of $P^M_{\lambda}$-policy proposed to control finite dams, and also an extension of the well-known D-policy. The distributions of the stationary workload of $P^M_{\lambda}$-service policy and its variants are studied well. However, there is no known result on the sojourn time distribution. We prove that there is a relation between the sojourn time of a customer and the first up-crossing time of the workload process over the threshold ${\lambda}$ after the arrival of the customer. Using the relation and the duality of M/G/1 and G/M/1 queues, we obtain conditional sojourn time distributions in M/G/1 and G/M/1 queues under the policy.
Bandwidth allocation for fluid input generalized processor sharing servers
Sunggon Kim,Ju Lee,Dan Sung IEEE 2010 IEEE TRANSACTIONS ON COMMUNICATIONS Vol.58 No.5
<P>Generalized processor sharing (GPS) service policy is a scheduling algorithm to allocate the bandwidth of a queueing system with multi-class input traffic. Simulating the GPS system in realistic traffic environments requires a large amount of time. Thus, fluid simulation is useful because it requires much less time. We analyze the bandwidth allocation for fluid simulation in GPS servers, in which the traffic into the server is treated as fluid. Three properties which characterize GPS servers with fluid input are discussed. We show that there exists a unique bandwidth allocation with the properties. It is shown that our previously proposed algorithm gives the unique bandwidth allocation and it is equivalent to the well-known Newton-Rapson method. In numerical study, the performance of finding the unique bandwidth allocation based on other known root finding methods is compared with that of our previous algorithm. We also investigate the impact of the length of the unit time on the accuracy of the performance measures.</P>
A Level Crossing Approach to the Analysis of Finite Dam
Kim, Sunggon,Lee, Eui-Yong The Korean Statistical Society 2002 Journal of the Korean Statistical Society Vol.31 No.3
We consider a finite dam with general inputs and adopt the level crossing approach to obtain explicit formulas of the expected wet period, the expected loss of water due to overflows in a wet period, and the long-run proportion of loss in inputed water.
Importance sampling with splitting for portfolio credit risk
Kim, Jinyoung,Kim, Sunggon The Korean Statistical Society 2020 Communications for statistical applications and me Vol.27 No.3
We consider a credit portfolio with highly skewed exposures. In the portfolio, small number of obligors have very high exposures compared to the others. For the Bernoulli mixture model with highly skewed exposures, we propose a new importance sampling scheme to estimate the tail loss probability over a threshold and the corresponding expected shortfall. We stratify the sample space of the default events into two subsets. One consists of the events that the obligors with heavy exposures default simultaneously. We expect that typical tail loss events belong to the set. In our proposed scheme, the tail loss probability and the expected shortfall corresponding to this type of events are estimated by a conditional Monte Carlo, which results in variance reduction. We analyze the properties of the proposed scheme mathematically. In numerical study, the performance of the proposed scheme is compared with an existing importance sampling method.