• Explosives and Blasting
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• v.36 no.1
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• pp.12-19
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• 2018

When an underground limestone mine selects room-and-pillar mining method, in which the stability of mine openings is maintained by leaving safety pillars, the stability of safety pillars is always incompatible with their productivity. Therefore, the engineering decision for stability and productivity is essential. In this study, a progress of excavation faces by conventional blasting pattern has been examined in field for investigating over-break and stereo-photogrammetry method has been applied to this field measurement for improvement of accuracy. Also this result has been reflected instantly to composite blasting pattern by feedback, for minimizing overbreak. Field tests showed the relevant results that $3.5m^2$ in over-break out of $70m^2$ in total excavation face has been decreased, that is 5% of reduction rate in maximum.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.4 no.3
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• pp.537-548
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• 2000

ATM is the effective information transmission method which multiply statistical and can accept effective the traffic of the various transmission rate. However, it can happen excessive cell loss probability and cell delay when it have temporarily overload. Therefore, it is required the effective traffic control and network resource management for which guarantee QoS(Quality of Service) in terms of users and bandwidth utilization maximization in terms of networks. In this paper, we proposed POBP(PushOut BP) scheme which mixed pushout scheme with BP(Back Pressure), reactive control scheme recommended at the ATM Forum, to guarantee QoS in two stages ATM switch networks. In proposed method, we have to understand exactly using bandwidth information in real-time and become traffic shaping. Thorough these processes, we can not only use effectively unused bandwidth, but also guarantee the fair bandwidth utilization and then can improve cell-loss possibility happened by congestion states in two stage ATM networks.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.11 no.4
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• pp.79-89
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• 2016

FDI has been considered as a source of competitive advantage by bringing scientific and technological innovation capabilities to domestic firms via organizational learning. Acquiring knowledge and technology by learning accelerates firms to be innovative. In the way of innovation, firms seek for innovation as a whole but innovation can be clarified as two different parts, product and process innovation. Different from product and process innovation, organizational innovation is not directly related to productivity or outcome but it is closely related to product and process innovations. As a kind of firm innovation, organizational innovation may be considered as preceding product and process innovation and it may positively mediate the relationship between in-bound FDI and firms' product and process innovations. In this paper, the relationship between FDI and product and process innovation will be explained by organizational learning and the way of organizational innovation affects to the relationship will be examined.

• Proceedings of the Korean Information Science Society Conference
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• 2005.07a
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• pp.640-642
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• 2005

분산된 컴퓨팅 환경은 프로세서의 개수를 적응적으로 활용하는 병렬 처리 환경으로 활용할 수 있다. 병렬 처리예 의한 수행 시간 단축 효과에 가장 많은 영향을 주는 것은 활용되는 프로세서의 개수와 병렬 처리 요소 상호 간의 통신 오버헤드이다. 분산된 컴퓨팅 환경으로 구성한 병렬 처리는 통신 오버헤드에 의한 단점과 프로세서의 개수를 자유롭게 활용할 수 있다는 장점이 상반되는 특성을 가지며 레이트레이싱에 의한 렌더링과 같이 계산량이 많고 병렬 처리 요소 상호 간의 통신량이 적은 응용 분야에 효과적이다. 분산된 컴퓨팅 환경을 병렬 처리에 활용하기 위하여 기존의 분산 처리 모델을 적웅용면 통신 오버헤드 이외에 부수적인 오버헤드(프로그래밍 및 확용 절차)로 인하여 실효성을 발휘하기 어렵다. 단일 컴퓨팅 환경을 위한 절차와 서비스를 그대로 적용하여 분산된 컴퓨팅 환경을 구성하는 여러 대의 컴퓨터를 통합하여 활용하는 방안은 이와 같은 부수적인 오버헤드를 해결할 수 있으며 본 연구팀에서 이미 발표한 TORB(Transparent Object Request Broker)는 프로그래밍 투명성의 제공을 통하여 분산된 컴퓨팅 환경을 활용하기 위한 프로그램을 단일 컴퓨팅 환경을 위한 프로그래밍 기법을 적응하여 작성할 수 있도록 지원한다. 지속적인 연구를 통하여 프로그래밍 투명성의 범위를 확장함과 동시에 활용 절차의 투명성을 지원하는 방안을 추가하였고 새로운 분산 처리 모델을 설계하여 이러한 절차와 서비스를 체계적으로 정립하였다. 인터넷에 연결된 컴퓨터는 적절한 수준의 컴퓨팅 능력을 갖추고 있고 상호 간의 정보 교환을 할 수 있는 상태이므로 "TORB"와 같이 잘 정의된 패러다임으로 이들을 통합하여 운영하면 병렬 처리에 참여하는 프로세서의 개수를 자유롭게 활용하여 수행시간 감소 효과(병렬 처리에 의한)를 극대화할 수 있다. 그러나 인터넷을 기반으로 하는 분산된 병렬 처리를 지원하기 위해서는 "TORB"가 이미 제공하는 투명성 외에 불특정한 타인이 작성한 프로그램 코드가 "TORB"를 통하여 자신의 컴퓨터에서 실행되어도 악의적인 동작을 수행하지 못하게 하는 보안 기능과 인터넷에 연결된 방대한 수의 컴퓨터를 "TORB"에 의해 구성되는 분산된 컴퓨팅 환경에 참여시키는 시나리오가 필요하다.

• Membrane Journal
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• v.13 no.4
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• pp.268-282
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• 2003

Pervaporation-facilitated esterification with slow reaction regime was characterized by using a practical model based on non-perfect separation through membrane. A non-perfect separation in which the membrane is not perfectly permselective to water was applied to the model. Thus, membrane selectivity and membrane capability to remove water were included in the simulation model to explain how they influence the membrane-facilitated reaction process and improve the reactor performance. It was shown by simulation that in the reaction systems with non-perfect separation, reaction completion can hardly be achievable when any reactant at initial molar ratio=1 or the less abundant reactant at initial molar ratio>1 permeates through membrane, and the permeation of ester accelerates the forward reaction md increase reaction conversion at any instant through removal of product species like water. The volume change causes concentrating both reactants and products that affect the reaction with time in opposite ways; reactant-concentrating effect is dominant during the initial stage of reaction, increasing the reaction rate, and then concentrating product influences more reaction by decreasing the reaction rate.

• The Journal of the Korea Contents Association
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• v.14 no.10
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• pp.137-150
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• 2014

This study analyzes the perception of the old age life effects on the preparation for old age plan for veterans who are somewhat isolated from our society in spite of the increasing importance of the old age plan due to the rapid population aging society in Korea. The result of the study shows that meaningful differences in terms of characteristics of sociology of population are rank, level of education, religion, composition of family members in old age life plan in two parts(economic, leisure), whereas only property in physical part has a meaningful difference. That indicates the result was reflected by the character of military. The study on how veterans' perception of the old life affects the old age plan applied two contrasting factors - 'the successful perception of old age life' and 'the perception of expected matters in old age'. That represents those factors(economic, leisure) made positive effects on preparation for old age plan, but not in physical part. 'Expected perception of matters' made regulation effect, but 'success of old age perception' didn't in terms of regulation effect of learning activity as part of the veterans vocational training programs.

• The Journal of the Korea Contents Association
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• v.16 no.4
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• pp.455-465
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• 2016

The purpose of this study was to examine the effect of twitter influenctials on users' willingness on express opinions. Based on the spiral of silence and corrective action hypothesis, the contradictory hypotheses were drawn. The online expeiment was conducted to verify which hypothesis is valid. Participant were assigned to the four experimenatal conditons: a famous influential's twit which agrees with the issue; a famous influential's twit which disagrees with the issue; an ordinary influential's twit to agree with the issue; an ordinary influential's twit to disagree with the issue. Results showed that opinion congruency with a twitter influential did not influence participants' willingness to express opinion online and offline, but the interaction effect with the type of influentials was found. Opinion dissonance with an ordinary tiwtterian increased willingness to express opinion. The findings suggest that twitter influentials, particulary an ordinary influentials with differnet opinions, can motivate users to express their own opinion.

• Informatization Policy
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• v.23 no.2
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• pp.35-53
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• 2016

This paper attempts to present critical issues of the information society and an alternative research addressing the challenges of ensuring that ICT is applied in ways that are enabling and responsive to social contexts in which people live their lives. Drawing the question of why insights arising from the mainstream vision are rarely useful in policies, the study highlights some developmental paradigms linked to ICT. It explores how ICT is seen as a means to development, and elaborates on the limitations of how current issues are related to the quality of life. The results indicate that ICT reduces quality of life while economic growth entails the opposite. The research framework here involves some meaningful components of cultural residues: independence, risk-taking, government responsibility by mapping how the level of ICT is distributed in the topology of values around the world. Moving to the next phase, ICT policy design and implementation need to be set up practically in a broad perspective that can be pursued by those concerned with social and technological innovation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.10
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• pp.6655-6665
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• 2015

Due to tightened environmental regulations on halogen type flame retardants, the portions of those based on phosphorous compounds that are non-halogen type is rising. When producing functional film, the physical and thermal properties become distinctly different depending on the amount of Red-phosphorus(RP) addition which causes flame resistance. The physical properties of resin fall in big scale when too much flame retardants are added, and it is hard to be applied to functional films such as shrink or anticorrosive film. The purpose of this research is to study the effects on mechanical, physical, and other properties of RP-LDPE films by changing the RP-MB contents. The LDPE film used for this study was produced through blow-type injection molding. The flame resistance was VTM-0, and the tear resistance showed inverse trends of MD and TD. Contraction percentage showed no relationship with the amount of RP content, but the anti-corrosive property showed 0.05 % better result than the national anti-corrosion shrink film reliability standard.

• Korean Journal of Social Welfare
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• v.59 no.4
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• pp.111-136
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• 2007

The National Basic Livelihood Security(NBLS) System implemented from October 2000 has expanded cash assistance to cover the poor who are able to work in our country. Although the cash assistance for them has positive aspects of providing basic livelihood security for all people, but many scholars have also pointed out its negative aspects such as a decrease in labor supply among the poor. In order to provide policy implications for the cash assistance program of our country as well as the US, this paper examines the impact of Temporary Assistance for Needy Families(TANF) on poverty among single mothers and their families using data from March Current Population Survey of $1991{\sim}2002$. TANF imposes strong work requirements and time limits to recipients as conditions for cash assistance, which are major sub-components of TANF. Therefore, this paper analyzes TANF by looking at work requirements and time limits separately, not by looking at TANF as a single policy. The research findings show that work requirements significantly decreased income and increased poverty among single mothers. Although time limits show income increasing effects and poverty decreasing effects, it seems further studies on time limits are needed at this point. The research findings of this paper provide important lessons for welfare to work cash assistance of our country as well as the US.