• 대한기계학회논문집
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• 제18권5호
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• pp.1218-1226
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• 1994

The shock tube is a useful device for investigating shock phenomena, spray combustion, unsteady gas dynamics, etc. Therefore, it is necessary to analyze exactly the flow phenomena in shock tube. In this study, the mechanics of its reflected shock zone has been investigated by using of the one-dimensional gas dynamic theory in order to estimate the transition from initial reflection of shock wave region. Calulation for four kinds of reflected shock tube temperature (i.e. (a) 1388 K (b) 1276 K (c) 1168 K (d) 1073 K) corresponding to the experimental conditions have been carried out sumarized as follows. (1) The qualitative tendency is almost the same as in that conditions in region of reflected wave region. (2) High temperature period (reflected shock wave temperature) $T_{5}$, exists 0-2.65 ms. (3) Transition period from temperature of reflection shock wave is far longer than the calculated one. This principally attributed to the fact that the contact surface is accelerated, also, due to the release of energy by viscoity effect. This apparatus can advance the ignition process of a spray in a ideal condition that involved neither atomization nor turbulent mixing process, where, using a shock tube, a column of droplets freely from atomizer was ignited behind a reflected shock.

• 한국인구학
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• 제18권2호
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• pp.51-69
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• 1995

이 연구는 한국사회에서 사회복지 정책을 어떻게 전개해 나가야 할 것인지에 관한 관심 속에서 선진복지국가인 스웨덴의 사회복지제도가 어떻게 발전해 나갔는지를 인구변천에 초점을 맞추어 살펴보고 있다. 먼저 스웨덴과 한국의 인구발전과정을 인구변천모형에 따라 분석하고, 인구변천 단계에 따라 사회복지가 어떻게 발전해 나왔는지를 주로 사회복지 법규를 통해 규명하고 있다. 다음 각 단계별 법규와 사회보장비 지출을 검토하여 스웨덴의 복지발달과정의 이념을 규명한 후, 한국의 사회복지정책이 어떤 방향을 나가야 할지를 제시하고 있다. 연구결과 스웨덴에 비해 한국의 사회보장비지출은 절대 부족상태이며, 스웨덴이 보편주의적 서비스를 강조하는데 비해 한국은 특수집단에 대한 서비스를 강조하고 있음이 부각되었다. 또 한국은 특수한 역사적, 문화적 요인에 의해 보훈계통의 비용이 지불되고 있다. 이 연구의 정책적 함의는 한국사회도 앞으로 소극적인 복지정책보다는 스웨덴에서 처럼 보편주의, 생산주의 및 가정복지를 바탕으로 한 복지민주주의 정책에 대한 적극적인 자세가 필요함을 제시하고 있다.

• 한국정보과학회논문지:시스템및이론
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• 제26권12호
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• pp.1468-1475
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• 1999

컴퓨터망 보안을 위해서는 취약점의 빠른 발견과 그에 따르는 신속한 조치가 요구된다. 이를 위해 컴퓨터망 여러 곳에서 사용자가 원하는 보안 정보를 수집, 분석하고 수집된 보안 정보들을 효과적으로 보여주는 통합적인 보안 관리를 제공하는 모니터링 방식이 필요하다. 본 논문에서는 보안 관리를 위한 동적 모니터링 형식 모델을 제시한다. 동적 모니터링은 상태 전이에 의한 시스템 상태, 사용자와의 상호작용, 시각 및 모니터링 객체의 동적 활성화를 이용하여 컴퓨터망 통합 보안 관리를 제공한다. 계속적으로 변하는 보안 정보, 컴퓨터망 관리자의 관심점과 모니터링 레벨의 변화를 즉각적으로 반영함으로써 관리자에게 컴퓨터망 관리의 정확성, 효율성 그리고 편의성을 제공한다. 모니터링 시스템을 형식적으로 모델링하여 여러 모니터링 응용프로그램의 개발이 가능한 모니터링 플랫폼으로 발전시킬 수 있다. Abstract It is highly required to quickly detect the vulnerability of a computer network system and an appropriate action toward it should be followed as soon as possible for its security. It leads us to the need of a monitoring schema that can provide an integrated security management with carefully selected and analysed data through the computer network for its users. This paper presents a formal model of dynamic monitoring for security management. It provides the comprehensive security management using continuously changing security information, user interactions and dynamic activation of visual and monitoring objects. It enables system security officers to manage computer systems accurately, efficiently and conveniently by reflecting the state transition and the transformation of concerns and a monitoring level of system security officers immediately. This model can be used as the basis of a monitoring platform.

• 한국정보과학회논문지:시스템및이론
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• 제32권7호
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• pp.333-340
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• 2005

네트워크 기반 컴퓨터 시스템이 외부 침입이나 혹은 내부 침입에 의해 부분적으로 손상 (Partially Compromised)이 되더라도 최소한의 필수 서비스를 지속적으로 제공할 수 있게 해주는 침입감내시스템(Intrusion Tolerance System) 설계에 요구되는 중요한 요소 기술 중의 하나는 컴퓨터 시스템의 정량적 신인도(Dependability) 분석이라 할 수 있다. 본 논문에서는 침입감내시스템의 방어능력을 확보하기 위해 자율컴퓨팅(Autonomic Computing)의 핵심 기술인 자가 치유(Self-healing) 메커니즘을 적용하였다. 주 서버와 보조서버로 구성된 침입감내시스템의 상태천이(State Transition)를 자가치유 메커니즘의 두 가지 요소(결함모델 및 시스템반응)를 활용하여 분석하였으며, 시뮬레이션 실험을 통해 침입감내시스템의 가용도(Availability)를 계산한 후, 두 가지 경우의 취약성(Vulnerability) 공격에 대한 사례 연구를 진행하였다.

• 대순사상논총
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• 제18권
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• pp.101-122
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• 2004

When people discuss the continental cultural elements in the ancient East Asian culture, people always attach great importance to the two major cultures of Confucianism and Taoism, but offer little explanation to the significant influence of the theory of yin and yang, the important philosophical base of the two major cultures. The theory of yin and yang, existing as the theoretical source at a profounder level, possesses philosophical connotations that are always embedded into the mainstream of thought, religions and customs, displaying its unique glamour in its unique way. Its influence is more than that, however. It has exerted far-reaching influence on and is of significant importance to the development of the ancient culture of East Asia. This article aims at exploring this field of study. After the erudite scholar of The Five Classics made a voyage to the east in the early sixth century, The Book of Changes, the most important Chinese ancient classic expounding the theory of yin and yang, started to circulate among the Japanese court, via Baiji in the Korea Peninsula. As a result, the theory of yin and yang found its way to Japan. Examining the spreading channels, we learn that the theory's dissemination was largely related to the activities of Buddhist monks. Shoutoku Prince, regent of Japan at the time, was himself an enthusiastic supporter of Buddhism and was excelled in the study of The Book of Changes and the theory of yin and yang. In the Twelve Ranks System and Seventeen-article Constitution promulgated by Shoutoku Prince, the influence of the theory of yin and yang and of the theory of the five elements can be visibly discerned. This obviously proves the sublime status of the Chinese theory of yin and yang in Japan, thanks to the victory of the political clique that adored Buddhism. In the shaping course of ancient Japanese culture, the theory of yin and yang served as an important philosophical source of its development. Mythology based on Kojiki and Nihon Shoki, two earliest Japanese books that exist today, record mythological stories about the emergence of the Japanese nation. The notion about the birth of heaven and earth and the forming of Japanese Shinto, expressed in the mythological stories, not only tell us the source and historical progress of the Japanese nation but also the nation's world outlook in the transition from barbarian period to civilized period, as well as the basis for its philosophical thinking. All these were marked with profound influence of the Chinese theory of yin and yang. The theory of yin and yang, as one of the ancient Chinese academic thoughts, was accepted asa political belief when it first spread to Japan. The emergence and establishment of both the Mikado system and the centralized regime in ancient Japan drew largely on the theory of yin and yang and adopted it as an important philosophical basis to deify and aggrandize the "imperial power" so as to protect the authority of the imperial ruling and consolidate the established regime. Following the continuous strengthening and expansion of the centralized state power, the theory of yin and yang was further employed, and gradually "hidden" in Japanese culture with the passage of time, finally becoming the edge tool of ancient Japanese Mikados in exercising political power and controlling the country.

• 대한화학회지
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• 제23권5호
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• pp.286-295
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• 1979

非對稱으로 置環된 diene과 dienophile 間의 反應에서 配向性에 미치는 산촉매의 효과를 豫期하기 위해서 루이스酸과 錯物을 形成한 dienophile의 理論的모델에 FMO 理論을 적용하여CNDO/2 방법으로 고찰하였다. 電子的性質이 類似한 치환기로 치환된 diene, dienophile의 반응(즉, 電子不足 diene과 電子不足 dienophile의 반응)에서 일어나는 半極性 고리化반응을 제외한 주어진 대부분의 반응에 대해서, CNDO/2방법이 실험적인 配向性과 一致하는 좋은 결과를 주었다. 또한 二次軌道相互作用이 非對稱으로 치환된 diene과 dienophile의 Diels-Alder 반응의 배향성에 중요한 역할을 했다는 사실을 보여주었다. Anh의 방법이 다른 방법보다 수식적으로 간단할지라도, 非對稱전이상태를 강조한 Anh의 방법이 配向性 결정에 좋은 결과를 주었다.

• Journal of Information Science Theory and Practice
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• 제3권3호
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• pp.17-44
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• 2015

Due to the oil business, settlements in the Gulf Region developed into prosperous cities. But in the near future, oil is off. The plans of the Gulf Cooperation Council (GCC) states bank on diversified and knowledge-intensive economies. Are those development plans realistic? What is the state of the art of knowledge institutions in the GCC countries? Applying the theoretical frameworks of Knowledge City and Science Indicators research, we empirically and theoretically studied the emerging Gulf cities Kuwait City (Kuwait), Manama (Bahrain), Doha (Qatar), Abu Dhabi, Dubai, Sharjah (all UAE), and Muscat (Oman). Our methodological framework includes grounded theory, ethnographic field study, ServQual-like quantitative questionnaires and semi-standardized qualitative interviews conducted on-site with informed people, informetrics, and, finally, the use of official statistics. In particular, we describe and analyze the cities' knowledge infrastructures, their academics, and expenditure on R&D as input indicators; and publications as well as graduates as output indicators. A further crucial aspect of a knowledge society is the transition of graduates into knowledge-intensive public services and private companies.

• Asian Journal of Atmospheric Environment
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• 제9권2호
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• pp.158-164
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• 2015

The estimation of the concentration of hydroxyl radical (OH) in the atmosphere is essential to build atmospheric models and to understand the mechanisms of the reactions involved in OH. Although water vapor is one of the most abundant species in the troposphere, only a few studies have been performed for the reaction of OH and water vapor. Here I demonstrate an ab initio study on the complex forming reation of OH with $H_2O$ in the gas phase performed based on density functional theory to calculate the reaction rate and the energy states of the reactant and the OH-$H_2O$ complex. The structure of the complex, which belongs to the Cs point group, was optimized at global minima. The transition state was not found at the B3LYP and MP2 levels of theory. Rate constants of the forward and the reverse reactions were calculated as $1.1{\times}10^{-16}cm^3\;molecule^{-1}\;s^{-1}$ and $5.3{\times}10^9\;s^{-1}$, respectively. The extremely slow rates of complex forming reaction and the resulting hydrogen atom exchange reaction of OH and $H_2O$, which are consistent with experimentally determined values, imply a negligible possibility of a change in OH reactivity through the title reaction.

• 인터넷정보학회논문지
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• 제19권2호
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• pp.89-98
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• 2018

Media industry is attempting various types of strategic innovation in the content and organization as they enter transition period. However, previous research has casually treated the organizational culture from the management and realized that cognitive/cultural differences between the specific departments yield conflicts. This means the researchers explored less on the decision-making process with the conflict between sub-groups and constituent in the organization. Our study reviewed the most positive method to achieve the innovation outcome through the conflict management within the organization based on the behavioral theory of the firm and applied computer simulation model for analysis to construct the quantitative scenario and infer the result. Conflict always found while media organization experiences innovation within the groups. However, in the long term, securing the independence through the certain state of 'anarchy' which possibly lead consensus implies significance rather to comprise collegiate system for unilateral control. In specific, this study explored the issues in 'conflict management' that has been evaded in media organization research through NK simulation model.

• Bulletin of the Korean Chemical Society
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• 제31권3호
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• pp.595-598
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• 2010

Ab initio and DFT molecular orbital calculations predict that acetyl radical reacts with acetylene through interactions primarily involving the SOMO of the radical and the in-plane ${\pi}$-bond of acetylene. An energy barrier (${\Delta}E_1$) of 39.6 kJ $mol^{-1}$ is predicted for the preferred anti arrangement of reactants at the CCSD(T)/cc-pVDZ//BHandHLYP/cc-pVDZ level of theory. NBO analysis reveals additional interactions between the radical SOMO and the nearby C-H ${\sigma}$-bond in acetylene worth about 10% of the total transition state interaction energy. This type of orbital interaction has not previously been observed in radical addition reactions involving C-C ${\pi}$-bonds.