• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.1192-1197
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• 2000

Piping systems of the power generating stations have been generally protected by hydraulic and mechanical snubbers which can allow large displacements arising from temperature change while those can reduce or absorb stresses due to vibrations. However these snubbers require amounts of budget for maintenance or replacement because of the leakage, lubrication and finally short life cycle. Recently the snubbers consisted of wire rope have been proved to reduce vibrations of piping systems. While the wire rope snubbers are free of maintenance such as leakage and lubrication, imported price are so high. Now it is necessary to design, manufacture and certificate these wire rope snubbers.

• Proceedings of the KWS Conference
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• 2010.05a
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• pp.48-48
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• 2010

소형 공조장치용 냉매 압축기 부품인 기계식 제어 밸브는 에어컨 컴프레서의 핵심부품이고 년간 수백만 개가 국내에 수입된다. 이를 국산화 하기 위하여 진공로 속에서의 브레이징 공정이 수반되는 외국제품의 제조공정을 탈피하여 진공 속에서 DC 프로젝션 용접을 수행하는 기법을 개발하였다. 실린더 형상의 캡과 케이스를 맞대고 그 사이에 박판을 삽입한 상태에서 butt welding 방식으로 진행되는 본 공정에서는, 생산성이 높고 서보가압 장치를 사용하여 soft touch 를 구현하므로 프로젝션이 손상되지 않은 상태에서 통전이 시작되고 2 단 가압 및 프로파일 가압이 가능하므로 링(ring)형상의 너깃이 축대칭으로 안정적으로 형성되기 때문에 실린더 내부의 밀봉성능이 우수함을 확인하였다. 진공로 속에서 본 가압장치를 설치하여 간편한 방법으로 실린더 내부의 진공상태를 유지할 수 있기 때문에 진공로 속에서의 브레이징 공정이 적용되는 외국제품보다 생산성이 월등함을 알 수 있다. 본 연구에서 개발된 링 프로젝션(ring projection) 용접기법은 초소형 및 소형 실린더 형상의 부품 내부를 진공으로 유지해야 하는 산업현장에서 당장 적용될 수 있는 혁신적인 용접공정이라 판단된다.

• Journal of the KSME
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• v.27 no.6
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• pp.504-514
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• 1987

복잡한 전자부품의 조립시에 필요한 열적 디자인에 관한 정보는 오래전부터 실험을 통하여 얻어지고 있다. 실험적 데이터를 이용하여 무차원 파라미터로 표시된 실험결과는 꼭 같지는 않지만 현상적으로는 비슷한 상황에 응용될 수 있다. 여기서는 학술문헌에 나타나 있는 자연대류에 관한 실험적인 상관관계식들과 프레임에 수직으로 꽂혀있는 균일가열 전자회로기판의 모델에서 얻어진 무차원 자료들을 비교하고자 한다. 대부분의 자료들은 수정채널 Rayleigh수(Ra")가 15~100범위에 속하며, 이러한 범위는 부품이 조밀하게 배치된 기관이 서로 좁은 채널을 이루고 있으며, 동시에 상당한 전력을 소비하고 있는 경우에 해당한다. Wirt와 Stutzman, Bar-Cohen과 Rohsenow의 일반상관관계식은 AT'||'&'||'T Bell 연구소에서 개발된 전자기기를 이용하여 수집한 실험데이터를 잘 표현하고 있으며 10 < Ra" <1,000범위에서 추천될 수 있다. 두개의 유사한 상관관계식과 비교할 때 상당히 좋은 예측을 보였으며 또한 Sparrow와 Gregg의 연구결과와도 잘 일치하므로 Ra" < 10인 경우에 Aung의 완전발달층류의 채널유동방식, Ra" > 1,000인 경우에는 Aung등의 단일 수직평판 근사식이 추천될 수 있다. Coyne의 알고리즘에 의한 계산치는 10

• Journal of agriculture & life science
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• v.43 no.2
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• pp.39-46
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• 2009

Ten animal hospitals in Seoul were selected, and of which 41,305 practice in total for recent 1 year were analyzed based on international classification of disease(ICD) of WHO. Of the entire practice, prophylaxis cases accounted for 42.2%. Of the 9,376 cases of internal diseases, digestive system diseases accounted for 4,957 cases(52.9%), respiratory system diseases 1,776 cases(18.9%), circulatory system diseases 1,239 cases(13.2%), and neoplasms diseases 413 cases(4.4%), respectively. In the estate investment expenses, to be specific, rental guarantee deposit accounted for about 50% of the entire estate cost, foregift(48%), and monthly rent(2%). Dividing the income of animal hospitals into medical service, articles selling, and pet-dog beauty, medical service accounted for 71.6% of the entire sales, selling of articles 16.7%, and pet-dog beauty 11.6%. Publicity work for the animal hospital was done mostly through web sites on internet(47%), then through local advertising papers(23.5%), and through bulletins and telemarketing(11.8%). Manpower of the animal hospitals in this study was mostly composed of veterinarians(45.5%) up to about half of the entire staffs, while there was no veterinary technician who had specialized education in that area.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.11
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• pp.1597-1603
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• 2011

The influence of heat-moisture treatment (HMT) and substitution of rice flour containing different amylose contents on the quality characteristics of rice noodles was investigated. HMT was applied to rice flours with 21% moisture content at 100 and 105$^{\circ}C$ for 30 min. Three rice cultivars were used, including high amylose of Goami (GM) and intermediate amylose of Choochung (CC) as domestic rice flours and imported rice of Taeguk (TG) as a control. HMT and substitution of rice flour with different amylose contents affected the cooking and texture quality of rice noodles. When rice noodles were made of intermediate amylose rice flour with HMT, cooking properties improved with decreased cooking loss and cooking water turbidity and thus were closer to those of control. Especially, the hardness, adhesiveness, tensile strength, and darkness of rice noodles notably increased when HMT rice flour was used. Based on the results of quantitative descriptive analysis for selected rice noodles, the noodles made of HMT CC at 105$^{\circ}C$ (CC105) had high scores for resilience and adhesiveness and low scores for hardness compared with imported commercial rice noodles and other experimental noodles such as TG, HMT GM100, TG+CC, and TG+CC105. In conclusion, rice noodles were made of composite flours containing high amylose and intermediate amylose contents or HMT intermediate amylose content rice flour.

• Journal of Korean Public Health Nursing
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• v.5 no.1
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• pp.53-69
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• 1991

가정간호사업 도입에 대한 대상자의 필요성에 대한 인식을 알아보고자, 1988년 7월 1일부터 동년 8월말까지 서울시내 5개 대학병원에서 퇴원하는 환자 390명과 환자 보호자 380명, 주민 780명, 총 1550명을 대상으로 조사한 결과 다음과 같은 결론을 얻었다. 1. $81\%$의 대상자가 가정간호 사업 도입이 필요하다고 한 반면 $7.5\%$는 필요 없다고 하였으며, $11.5\%$는 잘 모르겠다고 하였다. 필요성 인식 율은 주민이 $83\%$, 환자보호자가 $79\%$, 환자가 $78\%$로서 세 집단 간에 유의한 차이 가 있었다. (P<.01). 인구학적 변수별로 보았을 때, 교육수준과 가정수입에 따라 인식 율에는 유의한 차이가 있어서 (P<.001, P<.01), 교육수준이 높을수록, 수입이 많을수록 높았다. 2. 필요성 인식 율은 가정간호사업 이용의사에 따라서도 유의한 차이가 있어서 (P<.001), 이용의사가 많은 군이 인식 율도 높았다. 3. 환자들의 필요성 인식 율은 퇴원시기에 대한 의견과 병원비 지출액에 따라 유의한 차이가 있어서 (P<.05, P<.02), 퇴원시기가 적절하다는 군이 부적절, 하다는 군보다, 또한 병원비 지출액이 적을수록 인식 율이 높았다. 진단명에 따라서는 피부 및 피하조직 진환$(100\%)$, 임신 및 출산에 관련된 합병증$(90\%)$, 신경 및 감각기계 질환$(85\%)$, 부상 및 중독$(83\%)$, 신생물$(79\%)$, 등에서 필요성 인식 율이 높았다. 4. 가정간호사업 이용에 대한 대상자의 의견을 $47.8\%$가 이용할 의사가 있었고, $49.9\%$는 상황에 따라 결정하겠다고 하였으며, $3.2\%$는 이용하지 않겠다고 응답하였다. 인구학적 변수별로 보았을 때, 연령별로는 노년층, 성별로는 남성이, 교육수준은 낮은 군이, 의료보험을 가진 군이 이용할 의사가 많았으며, 통계적으로 유의한 차이가 있었다. (P<.01, p<.001, p<01, p<.01). 5. 환자들의 가정간호사업 이용 의사는 퇴원시의 상태에 따라서 유의한 차이가 있어서 (P<.02), 상태 가 입원 시와 변화가 없거나 악화된 군이 이용할 의사가 많았다. 진단별로는 내분비계 질환$(63\%)$, 신생물$(57\%)$, 혈액 및 조혈기능 장애$(55\%)$, 부상 및 중독$(55\%)$, 등이 이용할 의사가 많았다. 6. 대상자들이 가정간호사업의 장점으로 생각하는 것은 환자의 심리적 안정$(66\%)$, 시간 절약$(57\%)$, 가족의 편이$(57\%)$, 환자 간호에 대해 배운다$(53\%)$, 질병 과정을 배운다$(51\%)$ 등이었다. 7. 대상자들이 가정간호사업의 단점으로 생각하는 것은 응급시에 대처하기가 어렵다$(49\%)$, 환자가 불안해 할 것이다$(41\%)$ 가정환경이 환장에게 부적합하다$(43\%)$ 등이었다. 8. 가정간호사업에서 수용할 수 있는 간호 업무로$50\%$ 이상의 대상자가 지정한 것은 활력징후측정, 경구 및 비경구 투약, 운동과 휴식지도, 개인 위생관리, 보건교육, 정신 심리 간호 등이었다. 9. 가정간호사업에 대한 지불방법은 $32.9\%$가 제공된 업무에 따라 지불해야 한다는 의견으로 가장 많았다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.4
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• pp.331-336
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• 2012

This study was carried out to evaluate the wheat cultivation system to reduce costs and mechanize wheat production. A field study was conducted for 2 years (2009 to 2010) at the National institute of crop science, Iksan, Korea. We used working system I and working system II for the experiment. Working system I is used a multiple machine attached with a spreader tractor (seeding, fertilization, seed coverage, and weed control functionality) and working system II is used a multiple machine with a tractor which works for simultaneous job when seeding step (seeding, fertilization, and seed coverage). Sowing to harvesting operation time is 118 hours/ha for mechanize with conventional planting. Working system I is a multiple machine and a combine machine with a tractor, which worked 26 hours/ha lower than conventional planting. Working system II is 18 hours/ha lower than conventional planting. The reduced work efforts of working system I and II were 78% and 85% respectively. The growth and yield of wheat according to working system I and II is lower than conventional planting. Therefore, a multiple machine needs to study for appropriate seeding rate. Mechanization cost in consideration of the mechanical break-even point when the working system I is 3.7 ha and working system II is 4.2 ha. The farm income is enhanced by working system I (778,110 won/ha) and working system II (849,930 won/ha). The results showed that application of a multiple machine lowered costs of wheat production.

• Transactions of the KSME C: Technology and Education
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• v.3 no.4
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• pp.241-248
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• 2015

Most of the Stirling cryocoolers used for infrared detector cooling in domestic is imported. Because the cooler has a high price, short life and poor durability, demand for the coolers continues steadily. However, the cooler is highly related to defense and space technology, technology transfer or co-development with the countries having experties in cooler design is very limited. The pulse tube cooler to be developed in this study is such that the mechanical piston in low temperature actuating part is replaced by the gas piston and linear compressor is adopted, which results in low vibration, long life and better durability. It is expected that development of the pulse tube cooler will not only improve our technology to the level of advanced countries, but also enhance the skills in designing and manufacturing of the infrared detector.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.138-146
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• 1999

Textural properties of the cooked wheat noodles prepared from 5 Korean wheat varieties (Woori, Yeunpa, Allgeuru, Geuru, and Tapdong), and 3 foreign wheat varieties (ASW, WW and DNS) were evaluated by mechanical and sensory analyses, and their correlations to the physicochemical properties of the flours were examined. Cooking loss for noodle was negatively correlated with protein content, and weight increase during cooking showed a positive correlation with damaged starch content. From the mechanical tests, hard wheats (Tapdong and DNS) showed greater values for hardness, chewiness and tensile strength of the noodles than soft wheats. Foreign soft wheats (ASW and WW) showed relatively lower values for these attributes than the Korean soft wheats. Among the mechanical tests, multi-blade compression shear test had better correlations to the sensory characteristics than 10% compression, repeated compression and tensile tests. Among the flour characteristics, protein content was the most determining factor for the textural properties of noodle. Amylose increased the tenderness and slipperiness, but decreased internal firmness of the noodle. The Korean soft wheat noodles showed relatively darker color for the cooked noodle than WW or ASW. From acceptability test for noodle, Geuru was most preferred among the tested wheat varieties.

• Journal of the Korean Institute of Gas
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• v.24 no.3
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• pp.54-62
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• 2020

Watching the leakage accident of the Gumi Hube Global AHF(Anhydrous fluoric Acid), I experienced how much chemical accidents affect on our society. Since then, many studies have been conducted on chemical accident in many fields. The use department wanted to find improvement plans for the process system and apply them to the field. The safety field wanted to study improvement of safety through the analysis of damage effects and apply them to emergency response to reduce damage effects. In this study, Mechanical safe devices have been applied which can respond quickly to chemical accidents occurring during the charging operation to enhance the safety of the AFH ISO Tank(Anhydrous fluoric Acid International Organization for Standardization Tank). Investigation of similar tanks confirmed that other chlorine tanks with the same working procedure as AHF ISO Tank have a mechanical safety device, EFV(Excess Flow Valve). Applicability and performance for emergency shutdown when EFV is introduced in AHF ISO Tank can be verified by comparing and examining the accident situation of Hube Global Accident and the accident in Ulsan 2018. Comparing accident cases, expected performance and applicability, It is suggested that EFV, a mechanical safety device that can reduce damage from chemical accidents to the tank and handle accidents early, should be introduced to the tank.