• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.5
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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.

• Korea journal of population studies
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• v.18 no.2
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• pp.51-69
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• 1995

The Swedish welfare state has been the model for others to emulate the archetypical example of state intervention. The state interventions are presented in the form of legal acts. These social welfare acts can be classified according to the demographic transition theory. According to the Bogue's theory, the demographic transition in Sweden took place in four stages : the pre-transitional stage before 1810; the early transitional stage from 1810 to 1860; the mid-transitional stage from 1860 to 1930; the late transitional stage from 1930 to now. As we look into the social welfare acts in Sweden, the relief of the poor was the major concern of the early transitional stage, the care of workers was the major concerns of the mid-transitional stage and the care of the families was the major concerns in the late transitional stage. The Korea's transition period can be devided as follows; the pre-transitional stage before 1960; the early transitional stage from 1960 to 1969; the mid-transitional stage from 1970 to 1987; and the late transitional stage from 1987 to now. In Korea, the major concern of the early transitional stage was the care of the officials and the workers; in the mid-transitional stage the care of the aged and the handicapped were the major concerns. And in the late transitional stage the expanding of the welfare clients was the major concern. If we compare the results of both countries, the relief of the poor, the care of the workers and the care of the families will be the major concerns in Korea, because the social welfare acts in Korea are extended to specific groups and not to the whole population. The acts related to these social issues have been arranged in 120 years in Sweden. But Korea had to do the same work in 27 years. So the burden of making those social acts will be four times heavier. If we want to extend the benefits of the social system to the general population, we need to look at the design and approach of the swedish model. The reason why swedish social acts constitute an international model has more to do with the uniqueness of its design and approach. First of all, it is characteristic by its universalism, secondly by its emphasis on social services and thirdly by its productivitism. Also the swedish welfare state supported by a high-tax system called the earnings-related welfare system. In order to achieve an effective welfare state, we Koreans should pay attention to the relief of the poor, the care of the worker and the families. We should also focus on a good system design and prepare appropriate budgets.

• Journal of KIISE:Computer Systems and Theory
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• v.26 no.12
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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.

• Journal of KIISE:Computer Systems and Theory
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• v.32 no.7
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• pp.333-340
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• 2005

One of the most important core technologies required for the design of the ITS (Intrusion Tolerance System) that performs continuously minimal essential services even when the network-based computer system is partially compromised because of the external or internal intrusions is the quantitative dependability analysis of the ITS. In this paper, we applied self-healing mechanism, the core technology of autonomic computing to secure the protection power of the ITS. We analyzed a state transition diagram of the ITS composed of a Primary server and a backup server utilizing two factors of self-healing mechanism (fault model and system response) and calculated the availability of ITS through simulation experiments and also performed studies on two cases of vulnerability attack.

• Journal of the Daesoon Academy of Sciences
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• v.18
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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.

• Journal of the Korean Chemical Society
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• v.23 no.5
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• pp.286-295
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• 1979

In order to predict the effect of Lewis acid catalysis on the regioselectivity of the Diels-Alder reactions between unsymmetrically substituted dienes and dienophiles, the frontier orbital theory applied to the theoretical model of the Lewis acid complexed dienophile was studied by means of CNDO/2 MO. In the majority of reactions, CNDO/2 calculations gave good results in accordance with experimental orientation. Also, it was shown that the secondary orbital interaction played an important role in the regioselectivity of the Diels-Alder reaction between unsymmetrically substituted dienes and dienophiles. Although ANH's treatment is mathematically simpler than other methods, ANH's method which laid emphasis on dissymmetrical transition state gave good results on decision of regioselectivity.

• Journal of Information Science Theory and Practice
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• v.3 no.3
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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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• v.9 no.2
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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.

• Journal of Internet Computing and Services
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• v.19 no.2
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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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• v.31 no.3
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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.