• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.9B
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• pp.589-597
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• 2007

In this paper, a WDM metro ring consisting of access nodes with $FT-FR^n$ (Fixed Transmitter - n Fixed Receivers) is considered. A trade-off exists between node throughput and transmission fairness because the access nodes share wavelength channels. In order to eliminate the transmission unfairness and to increase throughput, the p-persistent medium access control (MAC) protocol is proposed: each node uses an empty optical slot to transmit a packet and make it available with the extraction of a transferred packet at the source access node, called source-stripping. The local empty slot can be used to transfer a head-of-line packet in the local buffer with probability p or it is used for the next downstream nodes with 1-p. The proposed MAC protocol provides better node throughput than the non-persistent protocol and exhibits better fairness index than the 1-persistent protocol in WDM ring networks. In addition, numerical analysis shows that the proposed MAC protocol maximizes the node throughput under uniform traffic conditions. For more detailed results, we use the network simulation under Poisson and self-similar traffic. Furthermore, unpredictable traffic constructed by the combination of the former and the latter is also considered. The reasonable probability of the p-persistent protocol for a given architecture can be determined through simulation.

• International Area Studies Review
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• v.21 no.4
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• pp.247-268
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• 2017

This paper analyzes for companies of 2011~2014 the effects of corporate social responsibility on audit efficiency. Using KEJI Index and its individual components which is published by Citizens' Coalition for Economic Justice Institute, this paper analyzes their effects on audit efficiency of audit fees and audit hours. The results of analyses are as followings. First, corporate social responsibility(CSR) composite index did not show any significant relationship between audit fees and audit hours. However, for analyses of the effects of CSR individual components on audit efficiency, variable such as CSR fairness(CSR2), CSR social contribution(CSR3), CSR environmental protection activity(CSR5) have the negative effects on the audit fees and audit time. and CSR customer protection(CSR4), CSR employee satisfaction(CSR6) have the positive effects on the audit fees and audit time. Results suggest that independent auditors may reduce audit risks associated with possible misrepresentation of financial statements for companies with high scores of CSR fairness (CSR2), CSR social contribution(CSR3), and CSR environmental protection activity(CSR5). Also, financial statement auditors may perceive surge of discretionary expenses, and set audit risk high for companies with CSR customer protection(CSR4), and CSR employee satisfaction(CSR6). Together, KEJI Index and its individual components appear to have differential effects on audit efficiency.

• Health Policy and Management
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• v.14 no.2
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• pp.17-33
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• 2004

The present study attempts to examine the progressivity of health care financial sources based on the income approach, for which it decomposes redistributive effects into vertical, horizontal, and re-ranking components. The study data include Korean Household Expenditure Survey (2000) conducted every 5 year by Korea National Statistical Office. The data were sampled from the national population by the multistage probabilistic sampling method, and amounts to 23,270 households. For the better application of the income approach, the study employs household total expenditure in Korea instead of total income, because the former data source is more reliable and less fluctuated over time. Progressivity of health care financing was measured by Kakwani index. Aronson's decomposition equation was used in case of the analysis where differential treatment of health care expenditure needs to be considered. Despite the progressivity of Korea's governmental contributions, total expenditure of health care showed regressive pattern, which may largely be attributable to the higher regressivity in out-of-pocket money. With the result of negative Kakwani index, differential treatment increased income redistribution biased for better-off. It is worth to note that social insurance displays not only negative Kakwani index, but also horizontal inequality, suggesting that the first step of health care financing reform should be the revision of social insurance premium rates toward effective and equable way.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.7
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• pp.63-73
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• 2015

In the end to end data transfer protocols, it is very important to correctly estimate available bandwidth. In UDT (UDP based Data Transfer), receiver estimates the MTR (Maximum Transfer Rate) of the current link using pair packets transmitted periodically from sender and, then sender finally decides the MTR through EWMA (Exponential Weighted Moving Average) algorithm. Here, MTR has to be exactly estimated because available bandwidth is calculated with difference of MTR and current transfer rate. However, when network is congested due to traffic load and where competing flows are coexisted, it bring about a severe fairness problem. This paper proposes a congestion degree based MTR estimation algorithm. Here, the congestion degree stands a relative index for current congestion status on bottleneck link, which is calculated with arriving intervals of a pair packets. The algorithm try to more classify depending on the congestion degree to estimate more actual available bandwidth. With the network simulation results, our proposed method showed that the fairness problem among the competing flows is significantly resolved in comparison with that of UDT.

• The Journal of Korean Medicine
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• v.37 no.3
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• pp.112-122
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• 2016

Objectives: This study aimed to assess the validity of 'Korean Diagnosis Related Groups-Korean Medicine (KDRG-KM)' which was developed by Health Insurance Review & Assessment Service (HIRA) in 2013 Methods: Among inpatient EDI claim data issued by hospitals and clinics in 2012, the data which included Korean medicine procedures were selected and analyzed. We selected control targets in the Korean medicine hospitals which had longer Episodes-Costliness index (ECI) and Lengthiness index (LI) than average of total Korean medicine hospitals, and compared the results of selection between the major diagnosis-based patient classification system and the KDRG-KM system. Finally, the explanation power (R2) and coefficient of variation (CV) of the KDRG-KM system using practice expenses were calculated. Results: The numbers of control target in Korean medicine hospitals changed from 36 to 32 when patient grouping adjustment method was changed from major diagnosis to KDRG-KM. For expenses of all outpatient claim data on Korean medicine, explanation power of KDRG-KM system was 66.48% after excluding outliers. CVs of expenses of patient groups in Korean medicine hospitals were gathered from under 70% to under 90%, and those in long-term care hospitals mostly belonged under 70%. Conclusions: The validity of KDRG-KM system was assured in terms of explanation power. By adapting KDRG-KM system, fairness of control targets selection for costliness management in Korean medicine hospitals can be enhanced.

• Land and Housing Review
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• v.2 no.3
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• pp.259-268
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• 2011

Space extension and the increase of the number of households are helpful to raise business value of the remodeling through the renovation of apartment houses that is required by residents of new cities and large-scaled apartment. However, in the case of accepting this demand, it could have a bad influence on the landscape of a complex in terms of the structure of apartment houses and the safety of construction and urban planning, and a problem occurs in the aspect of fairness for reconstruction. For the study, the current status related to the remodeling system through laws, related articles since 2000 and research data was analyzed. In addition, the individual quantitative analysis was conducted in the four aspects to judge whether households expansion for remodeling is plausible:1) Statistical data to comprehend the changes of population and social structure 2) Survey data of floor space index and the building-to-land ratio of new cities at the intial stage for the review of the effect of architectural planning and urban environment 3) Surveys of experts on structural safety in order to judge whether the demand of expansion is accepted or not. 4) Quantitative analysis of each item to compare fairness with reconstruction. Therefore, this study is intended to understand problems of the remodeling system that is currently operated. Moreover, it will be further reviewed that the expansion of households is feasible through the permission of expansion and it will be discussed that the revitalization of the apartment remodeling has a positive impact on the residential environment.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.1
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• pp.1-12
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• 2009

The purpose of this study is to discovered assessment items for improving athletic efficiency and management of golf courses. Through this, the study intended to provide basic data for creating competitive golf courses and management. Important assessment items were selected by inducing preliminary assessment items and conducting a preliminary survey and a main survey for specialists through a theoretical study. For the survey results studied, reliability and average value for importance were calculated using SPSS/PC Window Release 12.0. As assessment of importance by assessment area, in athletic efficiency assessment, course management level was the highest, followed by fairness of games and operation of games. In management assessment, importance of service level, information management, facility management, management of game assistants, etc. were high. As assessment of importance by assessment item, it was found that 'variety of golf shot' and 'the length of a course' were important in course layout. Also 'start interval among teams' and 'disturbance of play' were assessed as important items in game operation, while 'fair reservation' and 'rounding rotation time' were important in fairness of games. In addition, in information management, 'kind service of golf course staffs' and 'prompt reservation and notification' were found to be important assessment items. In facility management, all assessment indexes were over 4.0, which means all of them are important for quality of golf course and competitiveness. In membership service, 'appropriate price of goods for sale' and 'service for members' were relatively important assessment items. Further, in management of game assistants, 'qualifications and skillfulness of game assistants' was assessed as a very important index. Although the current study only selected important items to assess excellent golf courses, it is necessary to apply the study results to the actual sites and verify them for golf course both at domestic and abroad.

• Proceedings of the Korean Information Science Society Conference
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• 2007.10d
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• pp.261-266
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• 2007

UMTS release 5 에서 소개된 HSDPA 를 위해 도입된 새로운 기술 Adaptive Modulation and Coding, Hybrid Automatic Repeal reQuest, Fast Packet Scheduling 에 대해 알아보고 여기서 key role 이 되는 Fast Packet Scheduling 알고리즘 가운데 대표적인 세 가지 Round Robin(RR), Promotional Fairness(PF), Maximum Channel Quality Index(Max CQI) 알고리즘의 성능을 시스템 수율과 공평성의 관점에서 분석해보았다. 시스템 수율에서는 Max CQI, PF. RR 알고리즘 순이었으며 공평성 측면에서는 RR, PF Max CQI 알고리즘 순으로 나타났다. 같은 시스템, 같은 망 구조 내에서라면 알고리즘을 최적화하여 QoS와 성능을 극대화할 수 있도록 지속적인 연구가 필요하다.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.32 no.2
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• pp.29-37
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• 2009

National R&D programs play an important role in the development of a country in this age of the knowledge economy. Since many numbers of R&D programs compete for limited resources such as national R&D budget, the R&D program evaluation problem is a challenging decision-making problem faced by decision makers that deal with R&D management. In this sense, DEA(Data Envelopment Analysis) has been regarded as one of the most widely accepted methods to measure the relative efficiency of productivity of R&D programs. DEA is a methodology to measure and to evaluate the relative efficiency of a homogeneous set of decision-making units(DMUs) in a process which uses multiple inputs to produce multiple outputs. However, the sample of the R&D programs could consist of two or more naturally occurring subsets, thus exhibiting clear signs of heterogeneity such as different objectives. In such situations, the fairness of DEA is limited, for the nature of the relative efficiency of a DMU is likely to be influenced by its membership in a particular subset of the sample. In this study, we propose a methodology AI-DEA(attainment index DEA) allowing for reflecting decision maker's subjective judgement on difference among different subsets of R&D programs which have heterogeneous objectives. This methodology combines AHP and Delphi in order to decide the attainmnet index of each DMU for each outputs, and apply them to DEA model. We illustrate the proposed approach with a pilot evaluation of 13 programs involving 6 different subsets of Korean National R&D programs and compares the results of the original DEA model and AI-DEA model.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.11
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• pp.2621-2627
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• 2014

Directional transmission is one of key technology to solve the utmost problem that current mobile communication system faces, which is explosively increasing data traffic, since directional transmission can maximize the throughput of mobile communication systems. In this work, we consider power allocation scheme for mobile communication system which utilizing directional transmission. Especially, we consider the case in which multiple users in the same sector of base station, are served at the same time by utilizing directional transmission. For this scenarios, we consider equal power allocation scheme, Water-filling based scheme and inverse SNR scheme. Moreover, we propose beam power allocation scheme whose objective is to maximize overall system throughput by taking into account interference between different directional transmissions. Moreover, we have examined the spectral efficiency and Jain's fairness index of various power allocation schemes for directional transmission by using system level simulator that has been developed in our previous work. Through simulations, it has been verified that the proposed power allocation scheme can improve the spectral efficiency of the system by 28%.