• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.7A
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• pp.666-673
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• 2006

In this paper, we evaluated the performance of 4 types of ARQ algorithms that have been adopted to offer reliable transmission between MAC layers. First of all, we implemented IEEE 802.16 ARQ algorithms with NS-2 network simulator and then evaluated the performances in various channel states. We used two performance measures to evaluate those performances. First, we used the total number of ARQ block in bytes that have been received without error. Second, we used ACK_Efficiency that is newly defined in this paper. From the results of simulation, we could be aware that each ARQ algorithm has different performance in a various channel states. For improving the transmission data rate in a specific channel state, we have to choose the right ACK interval as well as a suitable ARQ algorithm.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.528-532
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• 2005

As the current IEEE 802.11 wireless LAN standard provides the unified channel access procedure for each traffic service without considering its own traffic characteristics, it is difficult to get its differentiated service qualities at IEEE 802.11 wireless LAN system. To solve this limit, IEEE 802.11e standard that can provide differentiated service to each traffic is under preparation. In this study, we implemented IEEE 802.11e EDCA channel access scheme with NS-2 simulator, and showed its numerical results in various system environments with using average delay and throughput as performance measures.

• Journal of Korean Society of Transportation
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• v.19 no.6
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• pp.171-182
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• 2001

Travel Time is an important characteristic of traffic conditions in a road network. Currently, there are so many road users to get a unsatisfactory traffic information that is provided by existing collection systems such as, Detector, Probe car, CCTV and Anecdotal Report. This paper presents the results achieved with Data Fusion Model, Hybrid Neuro Fuzzy System for on - line estimation of travel times using RTMS(Remote Traffic Microwave Sensor) and Probe Data in the signalized arterial road. Data Fusion is the most important process to compose the various of data which can present real value for traffic situation and is also the one of the major process part in the TIC(Traffic Information Center) for analyzing and processing data. On-line travel time estimation methods(FALEM) on the basis of detector data has been evaluated by real value under KangNam Test Area.

• Journal of the Korean Geotechnical Society
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• v.26 no.10
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• pp.69-79
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• 2010

To detect abnormal events in slopes, Principal Component Analysis (PCA) is applied to the slope that was collapsed during monitoring. Principal component analysis is a kind of statical methods and is called non-parametric modeling. In this analysis, principal component score indicates an abnormal behavior of slope. In an abnormal event, principal component score is relatively higher or lower compared to a normal situation so that there is a big score change in the case of abnormal. The results confirm that the abnormal events and collapses of slope were detected by using principal component analysis. It could be possible to predict quantitatively the slope behavior and abnormal events using principal component analysis.

• The Journal of the Korea Contents Association
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• v.14 no.5
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• pp.289-297
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• 2014

The purpose of this study was to investigate the relation between smartphone addiction and interpersonal competence of college students using social network service(SNS) through smartphones. This study used a descriptive study design. The convenience sample consisted of 502 college students in six cities. The data were collected from May to June in 2012 using Korean Smartphone Addiction Proneness Scale and Interpersonal Competence Questionnaire. Descriptive statistics, ${\chi}^2$-test, t-test, analysis of variance, and Pearson correlation coefficient were used to analyze the data. The results showed that 24.8% of SNS users were considered as a risk group, while 75.2% were normal user group. There were no significant differences of interpersonal competence between risk group and normal user group in the SNS users. However, risk group had higher self-disclosure scores than normal user group. The subjects who had higher scores for virtual life, one of smartphone addiction subdomains, had lower interpersonal competence and those with higher smartphone addiction scores showed lower score of managing interpersonal conflict in subdomains of interpersonal competence. These findings would contribute in development of preventive interventions for smartphone addiction and improvement program for interpersonal competence in college students.

• Journal of the Korean Data and Information Science Society
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• v.22 no.6
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• pp.1153-1166
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• 2011

Detecting misbehavior in vehicular ad-hoc networks is very important problem with wide range of implications including safety related and congestion avoidance applications. Most misbehavior detection schemes are concerned with detection of malicious nodes. In most situations, vehicles would send wrong information because of selfish reasons of their owners. Because of rational behavior, it is more important to detect false information than to identify misbehaving nodes. In this paper, we propose the variable precision rough sets based misbehavior detection scheme which detects false alert message and misbehaving nodes by observing their action after sending out the alert messages. In the proposed scheme, the alert information system, alert profile is constructed from valid actions of moving nodes in vehicular ad-hoc networks. Once a moving vehicle receives an alert message from another vehicle, it finds out the alert type from the alert message. When the vehicle later receives a beacon from alert raised vehicle after an elapse of time, then it computes the relative classification error by using variable precision rough sets from the alert information system. If the relative classification error is lager than the maximum allowable relative classification error of the alert type, the vehicle decides the message as false alert message. Th performance of the proposed scheme is evaluated as two metrics: correct ratio and incorrect ratio through a simulation.

• Journal of KIISE:Information Networking
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• v.30 no.4
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• pp.559-571
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• 2003

ENUM(tElephon NUmbering Mapping) is protocol that brings convergence between PSTN Networks and IP Networks using a unique worldwide E.164 telephone number as an identifier between different communication infrastructure. The mechanism provides a bridge between two completely different environments with E.164 number; IP based application services used in PSTN networks, and PSTN based application services used in IP networks. We propose a new way to organize and handle ENUM Tier 2 name servers to improve performance at the name resolution process in ENUM based application service. We build an ENUM based network model when NAPTR(Naming Authority PoinTeR) resource record is registered and managed by area code at the initial registration step. ENUM promises convenience and flexibility to both PSTN and IP users, yet there is no evidence how much patience is required when users decide to use ENUM instead of non-ENUM based applications. We have estimated ENUM response time, and proved how to improve performance up to 3 times when resources are managed by the proposed mechanism. The proposition of this thesis favorably influences users and helps to establish the policy for Tier 2 name server management.

• Proceedings of the Korean Information Science Society Conference
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• 2004.04b
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• pp.58-60
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• 2004

웹의 확산과 더불어 웹 페이지 검색의 성능 즉, 빠른 응답시간과 확장성(scalability)은 각 웹 사이트의 절대적 평가 기준이 되었다. 웹 옹용은 일반적으로 불특정 다수를 대상으로 하기 때문에 확장성 또한 주요 성능의 척도가 된다. 이와 같은 웹 사이트 성능을 담보하기 위한 대표적 요소기술이 웹 캐슁이다. 본 논문은 웹 상에서 XML 데이터베이스 기반의 웹 응용(XML database-backed web application)을 위한 응용서버의 XML 캐쉬를 이용하여 주어진 XML 질의를 변환, 처리하는 기법과 구현에 관한 것으로 XPath의 경로표현식 중 가장 중요한 세 가지 기능인 조건을 명시하는 필터 연산자, 부모-자식 관계를 나타내는 경로 연산자(/), 그리고 조상-후손 관계를 나타내는 경로 연산자(//)를 연구 범위로 하였다. [2]에서는 조상-후손 관계를 나타내는 경로 연산자(//)가 없는 경우에 경로표현식으로 주어진 XML 질의를 캐쉬를 이용하여 변환, 처리하는 알고리즘을 제시하였는데 본 논문에서는 [2]의 알고리즘을 확장하여 경로 연간자(//)가 지원되도록 하였다. 조상-후손 경로 연산자(//)로는 정규경로 표현식(regular path expression)을 나타낼 수 있는데 이는 스키마가 불확실한 반구조적 데이터인 XML 데이터에 대한 질의 표현에 유용하다. 제시된 알고리즘에서는 DTD를 이용하여 경로 정보를 얻어 처리함으로써 주어진 질의를 캐쉬와 하부 XML 소스에 대한 질의로 변환하였다. 이 알고리즘을 바탕으로 관계 DBMS를 이용하여 구현된 시스템으로 실제 웹 상에서 성능 실험을 수행하였다. 성능 실험 결과 정규 경로 표현식을 포함하는 XML 질의에 대해서도 웹에서 캐쉬를 이용한 처리가 효율적임을 확인하였다.키는데 목적이 있다.RED에 비해 향상된 성능을 보여주었다.웍스 네트워크상의 다양한 디바이스들간의 네트워크 다양화와 분산화 기능을 얻을 수 있었고, 기존의 고가의 해외 솔루션인 Echelon사의 LonMaker 소프트웨어를 사용하지 않고도 국내의 순수 솔루션인 리눅스 기반의 LonWare 3.0 다중 바인딩 기능을 통해 저 비용으로 홈 네트워크 구성 관리 서버 시스템 개발에 대한 비용을 줄일 수 있다. 기대된다.e 함량이 대체로 높게 나타났다. 점미가 수가용성분에서 goucose대비 용출함량이 고르게 나타나는 경향을 보였고 흑미는 알칼리가용분에서 glucose가 상당량(0.68%) 포함되고 있음을 보여주었고 arabinose(0.68%), xylose(0.05%)도 다른 종류에 비해서 다량 함유한 것으로 나타났다. 흑미는 총식이섬유 함량이 높고 pectic substances, hemicellulose, uronic acid 함량이 높아서 콜레스테롤 저하 등의 효과가 기대되며 고섬유식품으로서 조리 특성 연구가 필요한 것으로 사료된다.리하였다. 얻어진 소견(所見)은 다음과 같았다. 1. 모년령(母年齡), 임신회수(姙娠回數), 임신기간(姙娠其間), 출산시체중등(出産時體重等)의 제요인(諸要因)은 주산기사망(周産基死亡)에 대(對)하여 통계적(統計的)으로 유의(有意)한 영향을 미치고 있어 $25{\sim}29$세(歲)의 연령군에서, 2번째 임신과 2번째의 출산에서 그리고 만삭의 임신 기간에, 출산시체중(出産時體重) $3.50{\sim}3.99kg$사이의 아이에서 그 주산기사망률(周産基死亡率)이 각각 가장 낮았다. 2. 사산(死産)과 초생아사망(初生兒死亡)을 구분(區分)하여 고려해 볼때 사산(死産)은 모성(母性)의 임신력(

• Journal of Korean Home Economics Education Association
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• v.35 no.1
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• pp.105-124
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• 2023

The purpose of this study was to identify the characteristics of the contents included in the curriculum and 382 syllabi of the department of home economics education of College of Education in Korea and analyze the correlation by detailed area through the keyword network method. In order to analyze the home economics education curriculum and 382 syllabuses of a total of 11 universities, the frequency of keyword occurrence was analyzed using the KrKwic program, also the degree of connection between keywords and various centrality scales were calculated and visualized. The results of this study were as follows. First, as a result of analyzing the entire syllabi, keywords representing various fields such as family, secondary school, clothing, food, consumer, and design appeared evenly, and keywords related to teaching methods such as 'method', 'practice', 'change', and 'principle' were appeared. Those keywords showed high degree of connection and centrality. Second, in the detailed sectoral analysis, core keywords for each area appeared, and each subject were found to reflect the core keywords of the academic base. This study contributes to the conversion of curriculum of the department of home economics education to future-oriented and convergent curriculum.

• Cartoon and Animation Studies
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• s.29
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• pp.129-149
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• 2012

The purpose of this study was to investigate the clustering and Big Five Personality domains in discriminating groups by level of school-related adjustment, as experienced by Social Sims game users. Social Games are based on web that has simple rules to play in fictional time and space background. This paper is to analyze the relationships between social networks and user behaviors through the social games . In general, characteristics of social games are simple, fun and easy to play, popular to the public, and based on personal connections in reality. These features of social games make themselves different from video games with one player or MMORPG with many unspecific players. Especially Social Game show a noticeable characteristic related to social learning. The object of this research is to provide a possibility that game that its social perspective can be strengthened in social game environment and analyze whether it actually influences on problem solving of real life problems, therefore suggesting its direction of alternative play means and positive simulation game. Data was collected by administering 4 questionnaires (the short version of BFI, Satisfaction with life, Career Decision-.Making Self-.Efficacy, Depression) to the participants who were 20 people in Seoul and Daejeon. For the purposes of the data analysis, both Stepwise Discriminant analysis and Cluster analysis was employed. Neuroticism, Openness, Conscientiousness within the Big Five Personality domains were seen to be significant variables when it came to discriminating the groups. These findings indicated that the short version of the BFI may be useful in understanding for game user behaviors When it comes to cultural research, digital game takes up a significant role. We can see that from the fact that game, which has only been considered as a leisure activity or commercial means, is being actively research for its methodological, social role and function. Among digital game's several meanings, one of the most noticeable ones is the research on its critical, social participating function. According to Jame Paul gee, the most important merit of game is 'projected identity'. This means that experiences from various perspectives is possible.[1] In his recent autobiography , he described gamer as an active problem solver. In addition, Gonzalo Francesca also suggested an alternative game developing method through 'game that conveys critical messages by strengthening critical reasons'. [2] They all provided evidences showing game can be a strong academic tool. Not only does a genre called social game exist in the field of media and Social Network Game, but there are also some efforts to positively evaluate its value Through these kinds of researches, we can study how game can give positive influence along with the change in its general perception, which would eventually lead to spreading healthy game culture and enabling fresh life experience. This would better bring out the educative side of the game and become a social communicative tool. The object of this game is to provide a possibility that the social aspect can be strengthened within the game environment and analyze whether it actually influences the problem solving of real life problems. Therefore suggesting it's direction of alternative play means positive game simulation.