• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.33 no.2A
• /
• pp.191-197
• /
• 2008

For the efficient transmission of burst data in the time varying wireless channel, opportunistic scheduling is one of the important techniques to maximize multiuser diversity gain. In this paper, we propose a distributed opportunistic scheduling scheme for wireless LAN network. A proportional fair scheduling, which is one of the opportunistic scheduling schemes, is used for centralized networks, whereas we design distributed proportional fair scheduling (DPFS) scheme and medium access control with distributed manner. In the proposed DPFS scheme, each receiver estimates channel condition and calculates independently its own priority with probabilistic manner, which can reduce excessive probing overhead required to gather the channel conditions of all receivers. We evaluate the proposed DPFS using extensive simulation and simulation results show that DPFS obtains higher network throughput than conventional scheduling schemes and has a flexibility to control the fairness and throughput by controlling the system parameter.

• The Journal of the Convergence on Culture Technology
• /
• v.6 no.4
• /
• pp.477-482
• /
• 2020

Currently, suggesting directions for strengthening publicity of social services is thinking in the direction of each person's advantage from the stakeholder's perspective. The position of the service provider and the position of the user shows different opinions on the definition and evaluation of publicity of the city or province as the management entity. Therefore, this study combines opinions on publicity focusing on community service, derives consensus on the definition and evaluation of publicity, and evaluates different indicators or factors that cannot be quantified at the same time. The goal is to solve the problem of publicity by applying the Analytic Hierarchy Process(AHP) as a possible technique. In addition, in order to achieve the research objectives according to the designed frame, an empirical study was conducted by conducting a pairwise comparison questionnaire for experts and users. Through the AHP evaluation model" developed in this study, as a result of measuring the relative satisfaction of major factors, service utilization rate (0.470), facility management (0.210), and other project implementations (0.073) appeared in order. Here, the service utilization rate was evaluated as the most important.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2010.05a
• /
• pp.822-826
• /
• 2010

홍수피해저감 대책의 우선순위 결정은 시스템 차원에서 접근해야 한다. 홍수피해저감 사업을 분야별로 분리하여 분석하면 숲을 보지 못하고 산을 판단하는 오류를 범할 수 있다. 홍수피해 최소화를 위한 여러 전문 분야별 대안 분석도 중요하지만, 시스템 차원에서 홍수피해 저감 방안을 파악하고 대책을 수립해야 한다. 따라서 본 시스템의 개발 목적은 최적의 홍수피해저감 대책을 결정하는 데 있어 각각의 개별 정보를 공유하고, 의사결정 지원에 필요한 시스템을 구축하는 데 있다. 본 연구에서 제시한 홍수방어 대책 통합평가시스템은 수문학적 홍수분석 모형을 비롯하여 수리학적 홍수분석 모형, 의사결정지원 시스템이 통합되어 단일 시스템으로 구축되며 이를 위해서는 구체적인 사용자 요구파악과 관련 업무 프로세스 분석을 통한 전체적인 시스템 구조 설계가 중요하다. 홍수방어 대책 통합평가시스템의 핵심 요소는 1) GIS입력 모듈, 2) Fuzzy 알고리즘 모듈, 3) MCDA 알고리즘 모듈, 4) 결과표출 모듈 등 네 가지이다. 여기서 첫 번째 모듈은 GIS 입력 모듈로써 최적 방안 도출을 위한 빈도별 홍수터, 홍수심, 토지이용도 등과 같은 일련의 GIS 기초자료를 제공한다. 두 번째 단계는 퍼지화된 MCDA 모듈을 수행하기 위한 퍼지 알고리즘 및 퍼지 연산을 위한 내부 코딩이 이루어지는 단계로써 사용자 요구 사항에 따른 연산이 가능하다. 세 번째 단계는 최적 방안을 모색하는 MCDA 알고리즘과 연산 수행을 위한 세부 모듈로 구성됐다. 마지막 네 번째 단계는 모형과 DB간의 연계절차로써 사용자가 직접 운영하는 GUI 부분으로써 사용자의 요구 사항을 비롯하여 모형의 특징을 Matlab 프로그램으로 각각의 화면을 디자인한다. 이 단계에서는 모형을 수행하기 위한 DB가 구축되며 사용자의 요구에 의한 맞춤형 분석이 가능하도록 구성됐다. 통합시스템을 통한 의사결정과정의 합리성은 선택된 최적의 홍수저감대책의 사회 경제적 수용성은 물론 의사결정과정의 투명성을 높일 수 있을 것이다.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.41 no.4
• /
• pp.279-289
• /
• 2017

This paper presents some of the methods used to incorporate the parts constituting a product. A new relation function concept and its structure are introduced to analyze the relationships of component parts. This relation function has three types of information, which can be used to establish a relation function structure. The relation function structure of the analysis criteria was established to analyze and present the data. The priority components determined by the analysis criteria can be integrated. The analysis criteria were divided based on their number and orientation, as well as their direct or indirect characteristic feature. This paper presents a design algorithm for component integration. This algorithm was applied to actual products, and the components inside the product were integrated. Therefore, the proposed algorithm was used to conduct research to improve the brake discs for bicycles. As a result, an improved product similar to the related function structure was actually created.

• Journal of the Korea Convergence Society
• /
• v.11 no.9
• /
• pp.425-432
• /
• 2020

This study was to identify the educational needs for mental health nursing among undergraduate nursing students, prioritizing the areas where require extensive convergence learning via simulation. One hundred and forty students completed the survey where data accrued from between March-May 2020. The educational needs for mental health nursing and nursing care schizophrenia patients were assessed using a self-reporting questionnaire, which included 19 and 15 items, respectively. Additional three essay questions were used to obtain information regarding previous simulation education experience. Higher educational needs in nursing care for schizophrenia were identified and the highest-priority need is communication skills. Factors, including realistic experience with standardized patients, teamwork, and feedback from the lecturers, affect positive experiences in mental health nursing simulation. The findings suggest that educational programs to improve communication skills are necessary for better mental health nursing competency. Well-designed and convergence based simulation programs providing real-like clinical experience would ensure optimal learning outcomes.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.10 no.2
• /
• pp.257-263
• /
• 2006

With the ever increasing demand for data communication methods, powerline communication has become in interesting alternative method for data communication in home networking. For the purpose of home safety, several sensors will be installed at door, windows, gas alarm, etc. When considering home networking, the sensor data as well as other types of data should be supported in powerline communication. Usually the sensor data do not have priority over isochronous traffics (voice, video traffic), but in the case of urgent situation at home, the data of sensor being aware of the situation should be transmitted earlier than others. The objective in this paper is to develop a method for supporting an urgent data in home networking using powerline communication. We propose a modified algorithm of HomePlug 1.0 and show the results of computer simulation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 1999.11a
• /
• pp.270-273
• /
• 1999

Y2k will be able to enormous disaster. The many make an effort to find a solution to problem of Y2k. Problem of Y2k must solution to as follow. First, problem of Y2k solution organization must constructed. Second, in step with each stage-the first, developing and complete stage, stage of Y2k solution must be constructed. Third, solution of Y2k must construct to hierarchy. hierarchy structure constructed form six stage to first stage, first stage is investigation resources, second stage is estimation influence, third stage is planing conversion, fourth stage is working conversion, fifte spot, sixth stage is diffusion on the spot.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.28 no.8B
• /
• pp.707-715
• /
• 2003

In this paper, we propose a new MAC(Medium Access Control) protocol using Movable-boundary, which tries to guarantee Qos for multimedia traffic in the slotted CDMA system. In this scheme, the traffic scheduler assigns channel resource according to the packet priority per service class and adapts the Movable-boundary concept in which the minimum resource is assigned to each traffic class; the remaining resource if it is available can be assigned dynamically according to the temporal demand of other traffic classes. For performance analysis, we performed computer simulations to obtain throughput and packet loss rate and compared the results with Fixed-boundary system. We observed that the error rate of voice traffic could be maintained below a prescribed value while bursty traffic such as video source shares the same channel. In comparison with Fixed-boundary scheme, our protocol exhibits better throughput and packet loss rate performance.

• Journal of Korea Water Resources Association
• /
• v.39 no.1 s.162
• /
• pp.35-46
• /
• 2006

In this study, we proposed a layout of the integrated decision support system in order to prevent the contamination and to manage risk in water supply networks for safe and smooth water supply. We evaluated the priority of risk factors to detect anomaly in water supply networks using PROMETHEE and ANP techniques, which are applied to various Multi-Criteria Decision Making area in Europe and America. To develop the model, we selected pH, residual chlorine concentration, discharge, hydraulic pressure, electrical conductivity, turbidity, block leakage and water temperature as the key data item. We also chose pipe corrosion, pipe burst and water pollution in pipe as the criteria and then we present the results of PROMETHEE and ANP analysis. The evaluation results of the priority of risk factors in water supply networks will provide basic data to establish a contingency plan for accidents so that we can establish the specific emergency response procedures.

• Korean Journal of Social Welfare Studies
• /
• v.48 no.3
• /
• pp.209-232
• /
• 2017

This study proposes supplemental security income programs for the elderly to reduce the serious elderly poverty in Korea. The experiences of the supplemental security income programs for the elderly among the developed countries were investigated. Based on this, the Korean supplemental security income models were proposed, and the effects of the programs on the poverty, inequality, and finance were analysed. The results suggest the following implications. First, the supplemental security income programs cover a sizable portion of the elderly in Korea, and reduce substantially the poverty and inequality problems among the elderly. Second, the supplemental security income programs are efficient compared to the increase of the basic pension. Third, the effects were varied among the combinations of the basic pension models and the supplemental security income models. Therefore Korea needs to introduce an adequate policy mix consisting of basic income and supplemental security income programs so as to construct solid basic income security systems for the elderly.