• Korean Journal of Materials Research
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• v.15 no.9
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• pp.598-603
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• 2005

To develope new lead-free solders with the melting temperature close to that of Sn-37Pb$(183^{\circ}C)$, Sn-0.7Cu-5Pb-1Ga, Sn-0.7Cu-5Pb-1Ag, Sn-0.7Cu-5Pb-5Bi-1Ag, and Sn-0.7Cu-SBi-1Ag alloys were composed by adding low-netting elements such as Ga, Bi, Pb, and Ag to Sn-0.7Cu. Then the melting temperatures, microstructures, wettability, and adhesion properties of these alloys were evaluated. DSC analysis showed that the melting temperature of Sn-0.7Cu-SPb-1Ga was $211^{\circ}C$, and those of other alloys was in the range of $192\~200^{\circ}C$. Microstructures of these alloys after heat-treatment at $150^{\circ}C$ for 24 hrs were basically composed of coarsely- grown $\beta-Sn$ grains, and $Cu_6Sn_5$ and $Ag_3Sn$ intermetallic precipitates. Sn-0.7Cu-5Pb-1Ga and Sn-0.7Cu-5Pb-5Bi-1Ag showed excellent wettability, while Sn-0.7Cu-5Bi-1Ag and Sn-0.7Cu-5Pb-5Bi-1Ag revealed good adhesion strength with the Cu substrates. Among 4 alloys, Sn-0.7Cu-5Pb-5Bi-1Ag with the lowest melting temperature $(192^{\circ}C)$ and relatively excellent wettability and adhesion strength was suggested to be the best candidate solder to replace Sn-37Pb.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.365-369
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• 2002

Daidzein and genistein contents were determined for 46 varieties of soybean and several types of soyfoods using high pressure liquid chromatography. Average content of isoflavones in the soybeans was $809\;{\mu}g/g$ dry matter, ranging from 309 to $1610\;{\mu}g/g$, with Sinpaldal #2 and Dawon showing the highest and lowest amounts, respectively. Isoflavone contents of chonkukjang, soybean paste, and miso were 1045, 781, and $1067\;{\mu}g/g$, respectively. Isoflavone amounts in hard, semi-soft, soft, and fried tofus were 650, 895, 685, and $616\;{\mu}g/g$, respectively.

• Resources Recycling
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• v.25 no.6
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• pp.23-28
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• 2016

In this study, leaching process to extract phosphorus from the steelmaking slag was investigated for using the fertilizer resources of agriculture. In general, the phosphorus of steelmaking slag is formed as $C_2S-C_3P$ solid solution, and also, this solid solution is soluble in water more than the other phase in slag, and less than free CaO phase. In the present experiment, the influence of pH on the leaching behavior of various elements from the steelmaking slag was investigated by using multi-component steelmaking slag. When the pH was decreased, the concentration of Ca, Si, P and Fe in solution from the steelmaking slag was increased. Furthermore, at a pH of 3, the concentration of P ion in solution was decreased as leaching time increased. It is considered that the decrement of P was caused from the precipitation reaction between P ion and Fe ion in solution.

• Journal of the Korean Institute of Intelligent Systems
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• v.19 no.5
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• pp.720-724
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• 2009

This thesis analyze structure of consciousness of success factors of company project by applying FSM(Fuzzy Structural Modeling). FSM is a theory that implied fuzzy theory to ISM(Interpretive Structural Modeling) and is known to be more valid in recognizing a complex pluralistic value system and it is also designed to choose structure model that fits reality with when it is changed by parameter p and $\lambda$. It is desirable to conduct conformity assessment to complement even though selected structure model is considered as conformed because structure model is chosen without objective evaluation for conformity. Therefore, this paper present more objective structure model through conformity evaluation using structural equation modeling on success factors to achieve company project obtained by FSM and analyze the consciousness structure according to that structure.

• Korean Journal of Social Welfare Studies
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• v.48 no.4
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• pp.121-156
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• 2017

The purpose of this study is to examine the recovering gambling addicts' overcoming process on their hardships of life which hamper their recovery. For this study, we had one to one depth interview with 10 participants who had overcome their hardships of life after stopping gambling. The data gathered from the interviews were analysed following the grounded theory process suggested by Strauss and Corbin. As a result, 131 concepts were constructed, and they were classified into 32 subcategories and 14 category. We presented "overcoming of the hardships of life through the acceptance of reality and re-determination" as a core subject which connects the whole concepts. Based on the research outcomes, we proposed some policy and practice intervention methods such as economic self-support program, social security service, and triangle support system by counselor-family-peer recovering addicts.

• Journal of Korean Philosophical Society
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• v.144
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• pp.257-283
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• 2017

The purpose of this paper is primarily to examine models of collective decision-formation and decision-making. The goal is to propose a model of decision-formation and decision-making that is appropriate for a democratic society. Habermas distinguishes these models of decision-formation and decision-making by liberal, republican, and deliberative political models according to their justification types. Axel Honneth, on the other hand, is divided into three models of liberalism, proceduralism, and republicanism. I want to divide the model of possible decision-making in democratic society into three, that is, the model based on force, the model based on procedure, and the republican model. This distinction will identify the characteristics of each decision-making model and this confirmation will help us find the best decision-making model for a democratic society. In the end, I will combine the republican model with the procedural model. For this synthesis, I will also propose three conditions in modern society. I will argue that the three conditions of collective intelligence, active freedom, and horizontal networks are necessary.

• Korean Journal of Social Welfare Studies
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• v.49 no.3
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• pp.179-208
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• 2018

This study amis to analyze the levels of citizen inclusiveness in Korea by the 17 local government levels. Citizen inclusiveness was measured by donations, volunteering, and citizen perception indicators. This study adopted the ideal type method of fuzzyset analysis. We found that citizen inclusiveness was classified into 6 types: inclusive citizen type, inclusive citizen-oriented type, donation-oriented type, volunteering-oriented type, citizen perception-oriented type, and individual-oriented type. This study analyzed key features of these 6 ideal types of citizen inclusiveness. More research on citizen inclusiveness is needed. Trends of changes in citizen inclusiveness and key factors on citizen inclusiveness will be examples of future studies. Inclusive welfare states need both government's efforts in enhancing welfare institutions and citizens' advancement in inclusive citizenship. This study concludes with several implications for further developed citizenship for inclusiveness.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.256-256
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• 2017

최근 기후변화가 가속화되면서 집중호우가 급증하고 계획홍수량을 초과하는 홍수재해가 빈번하게 발생하고 있다. 이에 주요 선진국들은 홍수대응을 위한 새로운 패러다임을 도입하고 있다. 구조적 측면에서는 기존 제방 위주의 홍수방어에서 벗어나 유역에서 홍수 방어구획 설정, 대심도 터널 등 다원적 홍수방어체계로 전환하고 있다. 또한 ICT를 활용하여 다양한 수문정보를 실시간으로 관측하고 홍수상황을 신속하게 전파 대응할 수 있는 비구조적 대책도 적극적으로 개발하고 있다. 미국의 경우, 홍수량과 발생 확률을 예측한 정보를 시민들에게 조기에 제공함으로써 선제적으로 대응할 수 있도록 지원하고 있다. 그러나 우리나라의 홍수대응은 여전히 구조적 대책과 사후복구에 집중되어 있는 안타까운 상황이다. 세계 최고수준인 우리나라의 ICT 인프라를 이용하여 실시간 수문자료를 공유하고 이를 홍수대응에 활용하면 재난을 미연에 방지하는데 크게 기여할 수 있을 것으로 판단된다. 그러나 홍수관련 유관기관 자료를 연계한 실시간 수문상황 모니터링 시스템을 구축하는 것만으로는 지자체 홍수피해 저감에 한계가 있을 수 있다. 이를 보완하기 위해 수집된 실시간 수문정보를 활용한 홍수분석 및 하천수위별 대응기준 수립을 통한 예방적 재난대응 체계를 마련해야 한다. 이에 본 연구에서는 A지자체를 대상으로 홍수분석 모형을 구축하고, 구축된 모형의 계산결과를 활용하여 예상강우별 도달시간, 수위상승 등을 예측하고, 하천수위별 대응기준을 수립하는 연구를 진행하였다. 수위별 대응기준은 현장에서 계측되는 수위값을 기준으로 홍수예보기준, 하천기본계획의 제방고 및 주변 제약 사항을 고려하여 직접알람 기준으로 활용하였다. 또한 대상 수위국에 대하여는 2~3년간의 관측자료 확보 및 유량측정을 통해 대응기준의 보완을 진행할 예정이다. 재난관련 골든타임을 확보하고 홍수피해 최소화를 위한 홍수재해 통합관리 체계 구축은 이제 선택이 아닌 필수라 할 수 있다. 특히 본 연구로 산정된 홍수대응기준과 함께 물관리 유관기관의 실시간 수문자료 공유체계 구축, 홍수통제기관 또는 기술력을 보유한 재해대책 책임기관과의 유기적인 기술교류 등을 통해 지자체 홍수피해 저감을 위한 능동적인 홍수대응 체계 구축이 수행되어야 할 것이다.

• Journal of the Earthquake Engineering Society of Korea
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• v.25 no.3
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• pp.111-119
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• 2021

A shear wall is a structural member designed to effectively resist in-plane lateral forces, such as strong winds and earthquakes. Due to its efficiency and stability, shear walls are often installed in residential buildings and essential facilities such as nuclear power plants. In this research, to predict the results of the shaking table test of the three-story shear wall RC structure hosted by the Korea Atomic Energy Research Institute, three types of numerical modeling techniques are proposed: Preliminary, Calibrated 1, and Calibrated 2 models, in order of improvement. For the proposed models, an earthquake of the 2016 Gyeongju, South Korea (peak ground acceleration of 0.28 g) and its amplified earthquake (peak ground acceleration of 0.50 g) are input. The response spectra of the measuring points are obtained by numerical analysis. Good agreement is observed in the comparisons between the experiment results and the simulation conducted on the finally adopted numerical model, Calibrated 2. In the process of improving the model, this paper investigates the influences of the mode shape, material properties, and boundary conditions on the structure's seismic behavior.

• Journal of the Korea Convergence Society
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• v.12 no.12
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• pp.197-211
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• 2021

The emergence of knowledge-sharing live streamers provides more diversified content to the live streaming platform. Analysis of the factors affecting the intention to use knowledge sharing live streaming users can allow the live streaming platform to understand better the adoption characteristics of users who follow this type of content. Help platform operators provide better services and help live streaming platforms innovate. Based on the TAM model, this research uses questionnaire surveys and structural equation models to construct a conceptual model of the influencing factors of users' intentions in the knowledge sharing live streaming and conduct an empirical analysis on the influencing factor models. The results of data analysis show that a significant influence of users' attitudes of knowledge sharing live streaming is perceived usefulness, followed by flow experience; perceived value has a positive impact on users' attitudes and intention to use, and the positive influence of users attitude significantly affect the user's intention.