• Journal of the korean veterinary medical association
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• v.46 no.9
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• pp.816-821
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• 2010

일반적으로 알려져 있는 소에 있어서의 제각은 화학적인 소락제, 송아지 제각기 (tube calf dehorner), 전기인두, 톱 및 선거(線鋸; wire saw) 등을 이용하고 있으나, 제각 처치시 소에 많은 스트레스를 주고 있는 실정에 있다. 2001년도에 일본의 요우카이치시(四日市) 소재 냉동 및 냉장창고업을 하는 일신냉장고(주)에 근무하는 직원이 현내의 비육농장에서 제각하는 것을 보고, 생산자나 소비자로부터 이야기를 나누던 중, 점차적으로 소 사육농장에서 다두사육화가 되면서 우군 무리중에서 순위싸움으로 인해 외상을 입거나, 경쟁에 밀린 소는 사료를 제대로 먹지 못하여 스트레스를 받는 다는 것에 착안하여, 끝이 뾰쪽한 뿔에 복싱 글러브(boxing glove)와 같은 커버를 장착하면 제각을 하지 않고 소 본래의 자연체형을 유지한 체로 안심, 안전, 위험방지가 가능한 소의 뿔 커버를 연구개발하게 되었다. 최초로 제작된 소의 뿔 커버는 고무 특유의 수축작용을 이용해서 소의 뿔에 장착하였으나, 소의 큰 압력에 눌려 하루도 못가 각상피(角上皮)와 같이 탈락하였으며, 그 후 약 3년간은 실패를 거듭한 끝에 4년째인 2005년 봄에 의외의 장소에서 힌트를 얻었는 데, 귀가시 가족중 우연히 이가 빠졌는 것을 보고, 소의 각돌기(角突起)의 각첨부(角尖部)에 고정하는 방법을 생각하게 되었다. 연구를 시작하면서부터 NOSAI 수의사들, JA 동일본조합사료 수의사, 전농축산 서비스 등의 도움을 받았으며, 이후 오리온기업육성기술개발지원사업에 채택되어 4년여간의 연구를 한 끝에 약 30초의 부착시간이 걸리는 1회성의 영구적인 소의 뿔 커버를 특허개발(2005년)하여 2008년도부터 판매하기 시작하여 거세 화우, 교잡종 화우암소, 화우 암소 등에 일본 전역에서 보급되어 시술되고 있다. 최근 수개월전에 제가 아는 지인이 일본서 뿔 커버 2두분을 직접 구입하여 왔는 바, 직접 한우 경산우 암소 2두에 극히 간편하고 쉽게 시술하였기에 소개하여 도움을 주고 저 한다.

• Resources Recycling
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• v.9 no.6
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• pp.31-35
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• 2000

The complex permeability, the complex permittivity and the reflection loss are investigated in the composite microwave absorbers which are mixed with the wasted Mn-Zn ferrite and the industrial cement. The cement has larger the complex permittivity than that of the rubber. The complex permittivity is decreasing with the increment of the mixing ratio of Mn-Zn ferrite to cement (F/C in weight) and the complex permeability is increasing with the increment of F/C. The maximum reflection loss is above -40 dB at all samples. The matching frequency is in the range of 1.3 GHz to 2.9 GHz and is decreasing with the increment of F/C from 1 to 3. The matching thickness is increasing with the increment of F/C. The wasted Mn-Zn ferrite and the cement is very useful material for the composite microwave absorber.

• Elastomers and Composites
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• v.40 no.1
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• pp.3-11
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• 2005

The ruling kinetics of epoxy resins with 3 different kinds or alkenylsuccinic anhydride (ASA) having C-8, C-12, and C-16 pendant side chain length with two different catalysts was studied by using differential scanning calorimetry (DSC). Nonisothermal and isoconversional method has been used for characterizing the effect of the pendant side chain length in the curing process. Results or nonisothermal method showed that there was no significant difference in the effect of the pendant side chain length of ASA. But isoconversional analysis showed that the value of the activation energy for the initiation reaction or C-8, C-12, and C-16 were $61.7{\sim}57.7kJ/mol$, $63.0{\sim}57.3 kJ/mol$, and $130.4{\sim}94.2 kJ/mol$, respectively, depending on the catalyst used. The values of activation energy for the initiation is different as reported value of 20 kJ/mol which indicating the difference in the effect of the pendant side chain length of ASA in the initial stage of the reaction.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.9
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• pp.143-150
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• 2019

The purpose of this study was to propose how to determine the setting time related to the determination of the surface finish working time of the concrete using a Durometer, which is used as a rubber hardness meter. Two different types of Durometer were used to measure the setting time of the concrete. High flowing concrete with 40% of water to binder ratio was fabricated maintaining $600{\pm}100mm$ of slump flow. The test results indicated that the application of the Durometer resulted in a high correlation with the penetration resistance tester in both mortar and concrete. When measuring the setting time of the concrete, with properly used with Durometer, evaluation of the setting time of the concrete can be available. Therefore, it is thought that the measurement of the final set of the durometer C type can be useful to decide the limit time of the finishing operation and the time of the rejuvenation of the curing process by measuring the finishing set at 40 HD in the case of the initial set and 10 HD in the case of D type.

• Elastomers and Composites
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• v.37 no.4
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• pp.211-216
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• 2002

The polymer-polymer interaction parameter, x 23t, of the styrene-butadiene polymer (SBR) and ethylene-propylene-diene terpolymer (EPDM) was investigated by observing the phase behavior of the ternary system of SBR/EPDM/solvent. The solvent used in this study was benzene acting as a good solvent for SBR but as a poor solvent for EPDM. Ternary solutions with various concentrations and mixing ratios of the two component polymers were separated into two phases by temperature change The cloud point curves (CPC) showed that the differerence of solvent affinities toward each polymer and the repulsive interaction between two polymers considerably affect the shape of CPC near 15℃. In the temperature range of 5℃ ~ 25℃, incompatible behaviours arised from both the difference of mixing ratios and concentration were clearly observed. Also the phase separation temperature greatly influenced on the composition of each separated phase. The calculated x 23t values from Flory-Huggins theory were in the range of 0.6301 ~ 1.0775, which suggest that the SBR/EPDM systems are incompatible.

• The Journal of the Acoustical Society of Korea
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• v.26 no.6
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• pp.293-300
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• 2007

Turbulent boundary layer over an underwater vehicle is formed when it moves underwater and wall pressure fluctuation within the turbulent boundary layer generates flow-induced noise by exciting the elastic hull of the underwater vehicle. One of the methods to reduce this flow noise is to attach a compliant layer on the surface of the vehicle. In order to observe the possibility of noise reduction in the water when the compliant layer treatments are applied on the surface, three types of specimens those are a bare steel plate, a steel plate coated with neoprene and a steel plate with polyurethane coating material are tested at various flow speeds in a low noise cavitation tunnel. This paper presents the results of measurements and analysis of wall pressure fluctuations which is a main source of flow noise, within the turbulent boundary layer on three specimens. Its results could be shown that about 10dB reduction of wall fluctuation pressure at high frequencies was achieved due to the dissipation of turbulent energy by the compliant coating while it makes the turbulent boundary layer thicker and changes the behavior of turbulent flow in the layer.

• Elastomers and Composites
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• v.48 no.2
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• pp.148-155
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• 2013

The crosslinking density of polymer can be quantitatively calculated by the Flory-Rehner equation using the swelling experimental data and the lattice constant ${\beta}_1$ of interaction parameter (${\chi}$) in this equation should be chosen have used cautiously. This ${\beta}_1$ is the experimental data by rule of thumb, and researchers have used little different values respectively. Generally, the average molecular weight between crosslink points $M_c$ in the Flory-Rehner equation and the Mooney-Rivlin equation have the same value, and ${\beta}_1$ can be calculated when the $M_c$ in the Flory-Rehner equation is given. Therefore, in this research, firstly we calculated the $M_c$ using the selected ${\beta}_1$ (=0.34) and the swelling experimental data of 1,2,3-triazole polymer from the Flory-Rehner equation, secondly the $M_c$ from the Mooney-Rivlin equation is calculated by the tensile experimental data, and finally two $M_c$ were compared. As a result, two $M_c$ values were almost the same, and it was proved that the ${\beta}_1$ (=0.34) was selected properly.

• Journal of Service Research and Studies
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• v.12 no.3
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• pp.93-114
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• 2022

The hospitality and food service sector is the food sector that generates the most food waste. To deliver a more sustainable service, the food service industry needs to understand and reduce customer plate waste, which is mostly avoidable. Several studies have investigated the drivers of plate waste behaviors and proposed mitigations. However, service designers need actionable insights that inspire innovative solutions. The goals of this study are twofold. The first goal is to identify factors influencing young consumers' food waste behavior in restaurants. The second goal is to frame food waste challenges as design opportunities for service designers. A photo diary was conducted with 10 Korean university students. Participants took before and after photos of two meals and fill out questionnaires. The questions include personal background, considerations when choosing a meal, satisfaction with the meal, and reasons for leaving food. Both qualitative and quantitative data were collected and analyzed. The results suggest that lack of awareness and control are the key drivers of leftovers. The food waste problem is framed into "How Might We" design opportunities for service design. Interventions should focus on improving communication with oneself, dining partners, and restaurants. The paper contributes by demonstrating the service design research approach to framing wicked problems with the example of restaurant food waste.

• Journal of Wetlands Research
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• v.17 no.2
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• pp.184-192
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• 2015

This study is a basic research for low maintenance constructed wetlands which can prevent water quality deterioration due to wetland soils. The purpose of this study is to analyze water quality control mechanisms of constructed wetland on the artificial ground which installed the modular revetment structure(MRS), a device that separates water and soil. This study was then conducted with two different wetland mesocosms (a treatment plot and a control). These mesocosms were monitored to analyze effects of water quality control of the MRS. A treatment plot was built, and separated into soil and water, by filling the MRS with the decomposed granite soil in the mesocosm made of rubber material. A control plot was built where the decomposed granite soils were exposed to water by leaving the soil on the bottom of the mesocosm made of rubber material. Water quality was then analyzed by using Kolmogorov-Smirnov Z examination which then showed that pH, BOD, SS, Chl-a, T-P, T-N had statistically valid difference between a container with the MRS and one without it. According to the analysis of the water quality, the temperature and the EC level came out similarly and both mesocosm showed same level on pH and DO. A treatment plot had higher levels of BOD, SS Chl-a, and T-P. A control plot's T-N value was little lower than that of the treatment plot. This study suggests method of constructed wetlands using the MRS prevents problems occurring in wetland soils: aridity of wetlands by soil erosion, eutrophication, and algal blooms due to nutrients released from wetland soil. These functions of constructed wetland with the MRS increase aesthetic, ecologic, social, and economic value of the wetland. Outcomes of this research will later enable more proficient way of stabilizing water quality and provide data for planning low maintenance constructed wetlands.

• Cross-Cultural Studies
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• v.53
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• pp.103-130
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• 2018

The Chilean female writer María Luisa Bombal (1910 - 1980)'s "El ${\acute{a}}rbol$" (The Tree) (1939) tells the process of Brigida's epiphany. Brigida first tried to gain her father's love and failed, and later her husband's love and failed, then tried to substitute that love from men with solace from a tree. At the end of the novel, the epiphany occurs when the tree is cut down. In the present work, I explain the meaning of Brigida's epiphany, by comparing this Chilean short story with the Korean female writer Kim Chaewon(1946 - )'s "Trick of Water: A Kiss with Nothing" (2015). In this Korean short story, Kim insists that a woman who tries to find comfort in life through love with a man is destined to fail. I also examine the errors of the female characters' behaviors in these two short stories that led them to their self-destruction, trying to modify their behaviors in order to be loved by a man and their tendency to consider the man as everything in their life, and not as a part of their life. In order to explain the fated failure of finding comfort in life in the love of a man, I analyze the fleeting characteristic of acquiring an object of desire using Jacques Lacan's "Theory of Desire" and "The Destruction of the Elevated Object into the Dignity of the Thing." Thus, I conclude that women need to acknowledge that comfort in life cannot be found in the love of a man and that they should stop confining themselves to this fictitious characteristic of the dignified object called man.