• The Journal of Korean Institute of Communications and Information Sciences
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• 제28권8B호
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• pp.730-737
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• 2003

In this paper, we present an efficient authentication proxy for IEEE 802.1x systems based on the port-based access control mechanism. An IEEE 802.1x system consists of PC supplicants, a bridge with authentication client functions, and an authentication server. For the network security and user authentication purposes, a supplicant who wants to access Internet should be authorized to access the bridge port using the Extended Authentication Protocol (EAP) over LAN. The frame of EAP over LAN is then relayed to the authentication server by the bridge. After several transactions between the supplicant and the server via the bridge, the supplicant may be either authorized or not. Noting that the transactions between the relaying bridge and the server will be increased as the number of supplicants grows in public networks, we propose a scheme for reducing the transactions by employing an authentication proxy function at the bridge. The proxy is allowed to cache the supplicant's user ID and password during his first transaction with the server. For the next authentication procedure of the same supplicant, the proxy function of the bridge handles the authentication transactions using its cache on behalf of the authentication server. Since the main authentication server handles only the first authentication transaction of each supplicant, the processing load of the server can be reduced. Also, the authentication transaction delay experienced by a supplicant can be decreased compared with the conventional 802.1x system.

• The KIPS Transactions:PartC
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• 제16C권2호
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• pp.151-164
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• 2009

The importance of sensor networks as a base of ubiquitous computing realization is being highlighted, and espicially the security is recognized as an important research isuue, because of their characteristics.Several efforts are underway to provide security services in sensor networks, but most of them are preventive approaches based on cryptography. However, sensor nodes are extremely vulnerable to capture or key compromise. To ensure the security of the network, it is critical to develop security Intrusion Detection System (IDS) that can survive malicious attacks from "insiders" who have access to keying materials or the full control of some nodes, taking their charateristics into consideration. In this perper, we design a distributed and adaptive IDS architecture on sensor networks, respecting both of energy efficiency and IDS efficiency. Utilizing a modified HEED algorithm, a clustering algorithm, distributed IDS nodes (dIDS) are selected according to node's residual energy and degree. Then the monitoring results of dIDSswith detection codes are transferred to dIDSs in next round, in order to perform consecutive and integrated IDS process and urgent report are sent through high priority messages. With the simulation we show that the superiorities of our architecture in the the efficiency, overhead, and detection capability view, in comparison with a recent existent research, adaptive IDS.

• The Journal of the Korea Contents Association
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• 제17권9호
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• pp.88-98
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• 2017

The purpose of this study is to develop the teaching competency tool of university teachers with responsibility for college education and analyze the need for change. We have developed teaching competency to strengthen the competencies required for university professors' responsibilities and community activities in and out of universities and the contents validity was examined from 24 experts. The developed tools were used to diagnose the 83 teachers of K university in Chungcheongnam-do, and to derive basic competence, educational practice competence, and community competence through exploratory factor analysis and confirmatory factor analysis. The teaching competencies include 'Understanding of college education', 'Educational philosophy and attitude', 'Teacher attitude', 'Analysis design', 'Instruction execution', 'Guidance management', 'Evaluation feedback', 'Academic convergence', 'Sympathy learning culture', and 'Global sharing'. The results of the paired t-test and the analysis of the need for change through the analysis of Borich coefficient analysis were as follows: Understanding of university education (4th rank), analysis design (5th rank), instruction execution(2nd rank), empathy learning culture (1st rank), and global sharing (3rd rank). The competence of university teachers is not only the ability to practice teaching, but also the ability to understand university education and to empathize and share with the members of the university community. In the future, the university should actively develop and provide ongoing support programs to strengthen the capacity of professors.

• Journal of the Korean Geographical Society
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• 제41권3호
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• pp.283-300
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• 2006

Gaesung city of North Korea is meaningful because of the development of Gaesung industrial complex as a peace-building project and economical cooperation works between South Korea and North Korea. This article presents the characteristics of natural landscape of Gaesung through geographical names. This research was studied by literature analysis of North Korea, depth interview of North Korean labour and refugees, and second times fieldwork. The main results of this study are as follows. Firstly, the mountain landscape of Geasung revealed on geographical names characterized mountainousness and round shape. Especially, the places where are enclosed by mountain and streams are foggy and rocky. Next the landscape of stream characterizes sandy, unstable, and tidal river. Thirdly the fauna and flora which are reflected on geographical names are hawk, snake, tiger, homed owl, snapping turtle, chestnut tree, pine tree, pear tree, zelkova tree, and willow etcetera. The environmental conditions of habitation of these are similar to the natural environment of Gaesung. Besides, the geographical names related to soil distributed in northern mountain area of Geasung. The place names implicated cliff located on the riverside. In addition to this, the geographical name of 'Bul' implicated plain distributed in the riverside of 'Seoam' which a branch stream of 'Sacheo'. And the place names related rock located in place enclosed by mountain, river, and village. In cnclusion, Gaesung is more important to us as the Gaesung industrial complex and tourism development. But the fundamental research on Gaesung is a few because Gaesung belongs to North Korea. Therefore, this research will be useful for the control and management of Gaesung in the future.

• Proceedings of the Korean Information Science Society Conference
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• 한국정보과학회 2004년도 봄 학술발표논문집 Vol.31 No.1 (B)
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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 the Institute of Electronics Engineers of Korea TC
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• 제47권2호
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• pp.103-112
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• 2010

In sensor networks, because sensors are deployed in an unprotected environment, they are prone to be targets of compromise attack, If the number of compromised nodes increases considerably, the key management in the network is paralyzed. In particular, compromise of Cluster Heads (CHs) in clustered sensor networks is much more threatening than that of normalsensors. Recently, rekeying schemes which update the exposed keys using the keys unknown to the compromised nodes are emerging. However, they cause some security and efficiency problems such as single group key employment in a cluster, passive eviction of compromised nodes, and excessive communication and computation overhead. In this paper, we present a proactive rekeying scheme using renewals of duster organization for clustered sensor networks. In the proposed scheme, each sensor establishes individual keys with neighbors at network boot-up time, and these keys are employed for later transmissions between sensors and their CH. By the periodic cluster reorganization, the compromised nodes are expelled from network and the individual keys employed in a cluster are changed continuously. Besides, newly elected CHs securely agree a key with sink by informing their members to sink, without exchangingany keying materials. The simulation results shows that the proposed scheme remarkably improves the confidentiality and integrity of data in spite of the increase of compromised nodes. Also, they show that the proposed scheme exploits the precious energy resource more efficiently than SHELL.

• Korean Journal of Social Welfare Studies
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• 제37호
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• pp.429-455
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• 2008

The purpose of this study is to generate a substantive theory that accounts for the social readaptation of the women who have engaged in prostitution and propose a practical program for them. We used the grounded theory developed by Strauss and Corbin(1990). Raw data were collected through the in-depth interview, documents and observation. We used constant comparative method for the data analysis. The nine women who had the exprience of prostitution have participated in this study. As a result of the data analysis, in open coding were generated 116 concepts, 29 subcategories and 12 categories, In axial coding the outcomes of a paradigm model were as follows. The causal conditions were named 'hostile environment' and 'the self endowed stigma'. The phenomenon turned out to be 'living as an anonymous being'. The contextual conditions were named 'cohesion of family', 'being pushed' and 'shrinked emotion'. The intervening conditions were presented to be 'desire of self restoration as a social being', 'reactionary reconstruction'. The action/interaction strategies turned out to be 'shifting of social status', 'neighbor alliance'. The consequences were presented to be 'psychological wayfarer' and 'tentacular living'. In selective coding we found a core category, 'repetition of leaving and returning from the life world'. Based on the phenomenon, two types of participants life attitudes were found as follows : present hesitating type, self concealing type. Following the adove results, We finally suggested the need to develope a community oriented case management model.

• Review of Culture and Economy
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• 제19권2호
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• pp.97-120
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• 2016

This study aims to identify how performing artists in Korea, who are the target beneficiaries of the Arts Council Korea's Performing Arts Fostering Program, Chang-jak-san-shil(CJSS), would perceive and assess the current state of CJSS and its effects. To do so, this paper has adopted a bottom-up approach as a theoretical lens for policy evaluative analysis. This research engages with qualitative research design by conducting a series of in-depth interviews and FGIs with 28 participants in total. The interview participants consist of CJSS grantees(n=21) and peer-review panels(n=7) based on the intension to enhance objectivity and reliability of the study. Results of the data analysis suggest that the grant program still carries pressing needs to achieve a success as follows: providing post-program support, enhancing transparency of the panel appointment process and the peer review process, reflecting different nature of each arts discipline, and having more open communications with arts professionals. Based on these findings, this paper will provide and discuss about policy implications which can contribute to the performing arts domain at large.

• Proceedings of the Korea Water Resources Association Conference
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• 한국수자원학회 2018년도 학술발표회
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• pp.395-395
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• 2018

기후변화 및 토지이용변화에 따라 강우량 및 증발산량 등과 같은 물순환계 구성요소가 변화하면 유역에서의 물순환계가 영향을 받게 된다. 이렇게 변화된 유역의 물순환계를 종합적으로 관리하기 위해서는 물순환 개선 기술을 통한 지속가능하고 건전한 물순환체계의 구축이 필요하다. 유역 물순환 개선 기술은 기후변화가 진행 중에 있거나 예상되는 지역에 대하여 강우-유출수를 지연, 저류, 침투시켜 지속가능한 물순환체계를 유지 회복하도록 하는 기술이라 할 수 있다. 한국건설기술연구원에서는 기후변화 대비 수자원 적응기술 개발 연구단(CCAW, Climate Change Adaptation for Water resources)의 연구비 지원을 받아 유역 건전성 및 취약성을 평가 하고 취약한 유역에 대한 물순환 개선기술을 확보하기 위한 연구를 수행 중에 있다. 특히, 수년간 국가연구개발사업을 통해 개발되고 사업화에 성공한바 있는 유역 물순환 평가 모형인 CAT(Catchment hydrologic cycle Assessment Tool)을 수정 개선하여 수요자 중심의 활발한 현장 적용을 도모하고 있다. 본 연구에서는 개발된 유역 물순환 개선 및 평가시스템의 적용성 평가를 위하여 대상유역으로 태국의 Lam Takhong 저수지 유역을 선정하였다. Lam Takhong 저수지 유역은 유역면적은 $1,423km^2$이며 저류량은 약 $440{\times}106m^3$이다. 입력자료인 DEM, Land Cover 자료는 USGS Hydro1K (https://earthexplorer.usgs.gov/), 하천망 및 유역경계 자료는 USGS HydroSHEDS (https://hydrosheds.cr.usgs.gov/dataavail.php), 기상 및 관측 유입량, 저수지 제원 등의 자료는 APEC 기후센터의 협조를 받아 1976년부터 2016년까지의 일단위 자료를 이용하였다. 모의결과는 저수지 월별 관측 유입량과 상류 유역의 모의 유출량을 이용하여 비교-분석 하였다. Lam Takhong 저수지 상류 유역은 APEC 기후센터에서 SWAT 모형을 이용하여 저수지 유입량 분석을 수행한 바 있다. 따라서 본 연구의 결과를 SWAT 모의결과와 비교하여 그 적용성을 검증하였다. 월별 관측 유입량과 저수지 상류 유역 모의 유출량을 비교한 결과 CAT의 경우 결정계수(R2) 값이 0.86, SWAT은 0.76으로 나타나 CAT의 적용 결과가 좀 더 우수한 것으로 나타났다. 모의 결과는 매개변수 최적화 과정을 거치지 않은 결과이며 SWAT 모형과의 결과 비교를 위하여 매개변수는 동일하게 적용하였다. 향후 매개변수 최적화 모듈을 통해 검 보정 단계를 거친다면 정밀한 분석이 가능할 것으로 판단된다.

• Science of Emotion and Sensibility
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• 제22권1호
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• pp.45-54
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• 2019

Empathy has been observed to be pivotal in enhancing both social relations and the efficiency of task performance. Empathetic interaction has been shown to begin with individuals mirroring each other's facial expressions, vocal tone, actions, and so on. The internal responses of the cardiovascular activity of people engaged in empathetic interaction are also known to be synchronized. This study attempted to objectively and quantitatively define the rules of empathy with regard to the synchronization of cardiac rhythm between persons. Seventy-four subjects participated in the investigation and were paired to imitate the facial expressions of their partner. An electrocardiogram (ECG) measurement was taken as the participants conducted the task. Quantitative indicators were extracted from the heart rhythm pattern (HRP) and the heart rhythm coherence (HRC) to determine the difference of synchronization of heart rhythms between two individuals as they pertained to empathy. Statistical significance was confirmed by an independent sample t-test. The HRP and HRC correlation(r) between persons increased significantly with empathy in comparison to an interaction that was not empathetic. A difference of the standard deviation of NN intervals (SDNN) and the dominant peak frequency decreased. Therefore, significant parameters to evaluate empathy have been proposed through a step-wise discrimination analysis. Empathic interactions may thus be managed and monitored for high quality social interaction and communication.