• Journal of Welding and Joining
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• 제16권4호
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• pp.73-82
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• 1998

This paper is especially concerned with the weldment between support beam and square bar that plays important roles in control box of Expansion Joint as a brdige structure. Fatigue strength ({TEX}$$\sigma$_{ult}${/TEX}) of the weldment is dependent on notch factor ({TEX}$K_{f}${/TEX}) become important factors to predict fatigue life. The fatigue notch sensitivity (η) for metals can be divided into two types ; high and low notch sensitivity. In this work, the Expansion Joint weldment was found to have low notch sensitivity. The maximum strain distribution during static loading is similar to the FEM analysis. Fatigue test of real structure was performed up to {TEX}$10^{6}${/TEX} cycles to be compared with predicted endurance limit.

• 터널과지하공간
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• 제26권6호
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• pp.475-483
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• 2016

지하공동 굴착현장에서 관찰되는 절리분포 양상에 대한 자료를 기반으로 굴착과정에서 형성될 수 있는 사면체 블록의 형상, 규모 및 붕락 가능성을 절리 영속성을 고려하여 예측하는 수치해석 기법을 개발하였다. 절리 영속성 분석결과를 이용하여 절리면의 확장성에 따른 개착면에서의 표출정도 및 블록형성 가능성 해석을 수행하는 기능을 고안하여 기존에 개발된 결정론적 3차원 블록해석모델에 접목시켰다. 개선된 수치해석모델의 신뢰성을 고찰하기 위하여 실제 블록 붕락이 발생된 굴착현장에 대한 해석을 수행하였다. 조사된 절리분포 양상에 의거하여 대표 방향성을 설정하고 잠재적 블록 형성을 분석하여 붕락된 블록 형상에 부합된 해석 결과를 도출하였으며, 이에 근거하여 굴착과정에서의 붕락 진행 미캐니즘을 블록형상을 고려하여 고찰하였다.

• Progress in Superconductivity
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• 제3권1호
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• pp.104-110
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• 2001

Since the strand-to-strand type joint far CICC (Cable-In-Conduit Conductor) is small in size and has low DC resistance, it is expected to be useful type fur a superconducting magnet system which had a compact structure like the KSTAR (Korea Superconducting Tokamak Advanced Research) coil system. The DC resistance is changed according to the distribution patterns of strands in cables connected together in the joint. A commercial code was used for the calculation of the DC resistance. With the decrease of outer diameter of the Joint, Which means the increase of strand volume fraction in the joint, the calculated DC resistance decrease rapidly and non-lineally. The variation of resistance depends mainly on the volume fraction of solder which has higher resistivity than copper. The resistance decrease inversely with the increase of the length of the joint. The resistance increase with increase of number of triplets in each stack contacted with that of another terminal cable. In case of the strand-to-strand joint that has 62mm of outer diameter, 52mm of inner diameter, 100mm of overlap length, and four triplets in each stack, the calculated DC resistance is less than 1 n-Ohm.

• 유통과학연구
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• 제20권9호
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• pp.23-28
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• 2022

Purpose: Research on banking sustainability plays an important role in helping banks understand the level of risk in different types of companies. Therefore, this study was conducted to determine the factors affecting the sustainability of Joint Stock Commercia l Banks in Vietnam. Research design, data and methodology: The following theories, the factors affecting the bank's sustainability include: Business model diversification (income diversification), bank size, loan ratio, and net interest margin. Data was collected from Joint Stock Commercial banks in Vietnam from 2015 to 2019. With GLS model on panel data with banks listed on Vietnam stock exchange. Results: The analysis results show that net interest income has a positive impact on the sustainable business results of banks through the rate of return on total assets (ROA). The non-interest income hasn't impact on bank stability. From this result, there aren't positive signs of income diversification in banks. At the same time, with the obtained results, the study also provides a policy implication for banks. Conclusions: The study also provides some policy implications to improve the bank stability. Diversifying income in banks is necessary, but how to make it influential banks has not yet been done. Therefore, the adjustments in non-interest business activities need to be carefully considered by banks.

• Journal of Dairy Science and Biotechnology
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• 제17권1호
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• pp.32-38
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• 1999

Korean dairy industry is placed on the very critical situation with the progress of free trade marketing system internationally. To keep and improve the dairy food market, better measures are imperative for dairy industry. Especially, the milk distribution system is premodern to some extent, in comparison with both the production and the processing part of dairy industry. Reform measures for the promotion of domestic milk consumption by lowering the distribution cost are as follows. First, out-sourcing of the logistics department can decrease the circulation cost of milk. Secondly, milk should be packed into large-size package(more than 1 liter) to save both package and distribution cost. Thirdly, milk should be distributed from plant to consumers through the hygienic distribution system including perfect cold chain system, Above reform measures can not come true through the efforts taken by one company but through co-worker, concerted research, and joint in-vestment among dairy companies that can reduce the distribution cost and provide consumers with the best service, eventually resulting in the increment of milk consumption.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2006년도 추계학술대회
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• pp.134-137
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• 2006

Satisfying the customer orders with a short lead-time is one of the essential and competitive factors for business units under a mass customization environment. To shorten the lead-time for fulfilling various orders entails the production capacity expansion and efficient operational policy. Most business firms utilize the multiple production lines or facilities to cope with this business and manufacturing environment by making the manufacturing and distribution more flexible. In this study, we introduce the operational problem determining the joint production and delivery policy in an environment where multiple products are manufactured with more than one production lines. Also, we propose the heuristic solution approach for determining the product-line selection and joint lot size for this problem.

• Nuclear Engineering and Technology
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• 제33권6호
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• pp.605-618
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• 2001

For the mechanical stability assessment of a deep underground high-level waste repository. computer simulations using FLAC3D were carried out and important parameters including stress ratio, depth, tunnel size, joint spacing, and joint properties were chosen from sensitivity analysis. The main effect as well as the interaction effect between the important parameters could be investigated effectively using fractional factorial design . In order to analyze the stability of the disposal tunnel and deposition hole in a discontinuous rock mass, different modelings were performed under different conditions using 3DEC and the influence of joint distribution and properties, rock properties and stress ratio could be determined. From the three dimensional modelings, it was concluded that the conceptual repository design was mechanically stable even in a discontinuous rock mass.

• 한국정보컨버전스학회논문지
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• 제6권2호
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• pp.89-96
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• 2013

본 연구는 도매안경테의 종사자를 중심으로 안경테 유통을 분석하여 유통의 개선점을 연구하였다. 다양한 연령층과 학력으로 유통업계에서 근무를 하고 있으며, 회사의 규모는 영세하였다. 안경테의 재고 관리를 위해서는 체계적인 관리가 이루어지지 않았고, 보다 나은 유통 시스템에 대한 기대도 크지 않았다. 안경소비자와 안경제조업체의 중간적인 역할에 있는 도매안경테 회사는 보다 나은 판매 확보를 위해 공동 판매장이나 internet판매의 활성화를 확보하여야 할 것으로 본다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권5호
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• pp.1973-1991
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• 2018

Multimedia applications over wireless networks have been evolving to augmented reality or virtual reality services. However, a rich data size compared to conventional multimedia services causes bandwidth bottlenecks over wireless networks, which is one of the main reasons why those applications are not used widely. To overcome this limitation, bandwidth aggregation techniques, which exploit a multi-path transmission, have been considered to maximize link utilization. Currently, most of the conventional researches have been focusing on the user end problems to improve the quality of service (QoS) through optimal load distribution. In this paper, we address the joint pricing and load distribution problem for multi-homing in heterogeneous wireless access networks (ANs), considering the interests of both the users and the service providers. Specifically, we consider profit from resource allocation and cost of power consumption expenditure for operation as an utility of each service provider. Here, users decide how much to request the resource and how to split the resource over heterogeneous wireless ANs to minimize their cost while supporting the required QoS. Then, service providers compete with each other by setting the price to maximize their utilities over user reactions. We study the behaviors of users and service providers by analyzing their hierarchical decision-making process as a multileader-, multifollower Stackelberg game. We show that both the user and service provider strategies are closed form solutions. Finally, we discuss how the proposed scheme is well converged to equilibrium points.

• 지질공학
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• 제19권3호
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• pp.351-363
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• 2009

경상분지 내 구미노두와 다사노두 지역에서 신동층군의 사암층을 대상으로 절리 연구가 집중적으로 이루어졌다. 사암-이암 시퀀스의 양 지역 노두에서 똑같이 두 조의 직교 절리가 사암층에 전형적으로 발달하고 있다. 여러 가지 절리 자료들을 양 지역의 동일한 두께의 층에서 비교하여보면 상당히 유사한데 이는 절리 조들이 동일한 응력장에서 신장 변형 작용으로 균질하게 생성되었음을 이야기 한다. 대부분의 절리들은 퇴적물이 매몰되어 고화되는 과정에서 수압단열작용에 의해 생성된 것으로 생각되며, 사암층의 층 경계에 수직이고 층 경계에 이르러 중지한다. 두 조의 직교하는 절리들은 단열 격자차단 양상으로 해석되는 상호 접경하는 관계로 볼 때 ${\sigma}_1$은 수직으로 고정된 상태에서 ${\sigma}_2$ 와 ${\sigma}_3$의 빠른 교환에 의해 거의 동시에 생성된 것으로 판단된다. 사암층에서의 절리조들은 인접한 절리 간에 평행한 배향을 가지며 규칙적인 간격을 가지고 절리면은 평탄하다. 절리간격은 층 두께에 비례하고 간격분포는 대부분의 층에서 대수-정규분포 내지 정규 분포를 나타낸다. 그러나 다중층에서는 간격의 분포범위가 크고 불규칙한 형태를 보여준다. 연구지역에서 두 조의 절리들은 최빈값/평균값의 비가 1 내외로 포화상태를, 또 다른 척도인 변동계수(Cv)도 1이하의 낮은 값으로 포화를 지시한다. 절리의 개구는 모든 사암충의 절리에서 균질하기보다는 절리의 길이가 증가함에 따라 증가하는 경향을 갖는다.