• 제목/요약/키워드: Material screening

검색결과 286건 처리시간 0.032초

시중 컴프레션 티셔츠의 신장 특성에 대한 스크리닝 테스트와 의복압 예측 (A Screening Test of Extensibility and the Prediction of Clothing Pressure for Commercial Compression T-shirts)

  • 김남임;홍경희
    • 한국의류학회지
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    • 제41권6호
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    • pp.1010-1021
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    • 2017
  • Adjustment of clothing pressure for compression wear is critical to the physiological and psychological satisfaction of the wearer; however, there are limited studies on the practical relationship among extensibility of materials, pattern reduction of compression wear and resultant clothing pressure. This study provides consumers and designers with information on clothing pressure using a screening extensibility test suggested by Ziegert and Keil (1988) even for the final products. As the first step, ten commercial products were collected and their size, extensibility and corresponding clothing pressure were analyzed. It was found that clothing pressure around the waist level could be predicted well from the information of Ziegert and Keil's (1988) % extensibility of the material (Z stretch %) and the actual application of Z stretch amount to the pattern reduction rate (applied % of Z stretch), with an $r^2$ of around 0.80, especially at the waist level. However, it was not simple for the case of clothing pressure around the back of the chest level due to the various design variation and the complexity of the anatomical structure around the trapezius.

Transport Velocity of Perilla Grain on Oscillating Sieve in Elliptical Motion

  • Pang, Yeoun Gyu;Kim, Sang Hun
    • Journal of Biosystems Engineering
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    • 제43권3호
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    • pp.194-201
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    • 2018
  • Purpose: The objective of this study was to propose a formula for the theoretical grain mean transport velocities of an elliptically moving oscillator by modifying the grain mean transport velocity formula applied to linear motion and to compare the calculated values with the experimental values of grain mean transport velocity. Methods: The values of the throwing index ($K_v$) and the maximum horizontal velocities for various positions on the elliptical oscillator were obtained using kinematic analysis. To obtain the actual grain transport velocity, the mean transport velocities of perilla grains at six positions on the sieve surface were measured using a high-speed camera and compared with the theoretical values. The cam with an eccentric bearing on the oscillator was designed to be eccentric by 1.6 cm so that the lengths of the major axis of the elliptical motion were 3.2-3.6 cm. The material used in the experiments was perilla grain. Results: The experimental result was consistent with the theoretical value calculated using the proposed formula ($R^2$ is 0.80). It is considered that the angle difference between the maximum accelerations in the directions vertical and horizontal to the sieve has as much influence on the grain mean transport velocity as the value of Kv itself. Conclusions: It was possible to theoretically obtain the grain mean transport velocities through a screening device in elliptical motion by modifying the formula of the grain mean transport velocities used in linear motion.

Levitation characteristics of HTS tape stacks

  • Pokrovskiy, S.V.;Ermolaev, Y.S.;Rudnev, I.A.
    • 한국초전도ㆍ저온공학회논문지
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    • 제17권1호
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    • pp.14-16
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    • 2015
  • Due to the considerable development of the technology of second generation high-temperature superconductors and a significant improvement in their mechanical and transport properties in the last few years it is possible to use HTS tapes in the magnetic levitation systems. The advantages of tapes on a metal substrate as compared with bulk YBCO material primarily in the strength, and the possibility of optimizing the convenience of manufacturing elements of levitation systems. In the present report presents the results of the magnetic levitation force measurements between the stack of HTS tapes containing $n=2{\div}200$ of tapes $12mm{\times}12mm$ and NdFeB permanent magnet in the FC and ZFC regimes. It was found a non- linear dependence of the levitation force from the height of the array of stack in both modes: linear growth at small thickness gives way to flattening and constant at large number of tapes in the stack. Established that the levitation force of stacks comparable to that of bulk samples. The numerical calculations using finite element method showed that without the screening of the applied field the levitation force of the bulk superconductor and the layered superconductor stack with a critical current of tapes increased by the filling factor is exactly the same, and taking into account the screening force slightly different.

Recovery and Refining Process of Gypsum from Waste Plaster Board

  • Song, Young-Jun;Hiroki Yotsumoto
    • 자원리싸이클링
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    • 제10권6호
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    • pp.43-52
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    • 2001
  • This study was conducted to obtain granular crystalline gypsum that can be used as raw material for Plaster boards or cements from waste Plaster board. Gypsum could be Preferentially disintegrated to gypsum needle in $10\mu\textrm{m}$ or less size by hydration after the dehydration of crushed waste Plaster board. The finer the gypsum needle, it is easier to remove coarse impurities and to recover the gypsum needle. The optimum conditions for obtain the finer gypsum size were dehydration rate of 75~85%, solid concentration at hydration of 10~15%, agitation speed of 250~400 rpm, crushing size before dehydration of 2 cm or less. Gypsum of 98.21% grade was recovered with 99.0% yield as the undersize of 325 mesh wet screening followed by the dehydration-hydration process performed at the conditions of dehydration rate of 80%, solid concentration at hydration of 15%, agitation speed of 300 rpm, crushing size before dehydration of 2 cm or less. After the recrystallization of recovered gypsum, Plate-like gypsum of $151\mu\textrm{m}$ size with 99.49% grade was obtained as the oversize of 270 mesh in a wet screening.

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신생아의 Impedance audiometry (Studies in Impedance Audiometry on Neonates)

  • 오평;천경두;송재우;소진명
    • 대한기관식도과학회:학술대회논문집
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    • 대한기관식도과학회 1977년도 제11차 학술대회연제 순서 및 초록
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    • pp.4.2-4
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    • 1977
  • 1880년대 신생아의 중이강내에는 분비물 또는 기타 결체조직이 들어있어 중이강내의 정상적인 운동성을 방해한다는 등 여러 이론등이 있었고 1973년 DeDmon은 신생아의 screening에 있어서 acoustic reflex의 역활에 대한 보고가 있었으며, 1974년 Keith는 electro-acoustic impedance bridge를 사용하여 출생후 20시간 이내의 신생아 20명에 대한 결과등을 보고하였다. 우리나라에서는 아직 신생아에 대한 보고가 없어서 본원에서는 본원 산부인과에서 출생후 24시간 이내의 신생아 100명에 대한 tympanogram, static compliance 및 acoustic reflex 등에 관한 결과를 문헌고찰과 함께 보고하는 바이다.

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시멘트 혼화제 제조시 에스테르화공정의 열 안정성 평가 (An Evaluation of Thermal Stability on Esterification Process in Manufacture of Concrete Mixture Agents)

  • 이근원;이정적;최이락;한인수
    • 한국안전학회지
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    • 제24권4호
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    • pp.40-46
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    • 2009
  • The early identification of thermal hazards associated with a process such as the heats of reaction, exothermic decompositions, and the understanding of thermodynamics before any large scale operations are undertaken. The evaluation of reaction factors and thermal behavior on esterification process in manufacture of concrete mixture agents are described in the present paper. The experiments were performed in the differential scanning calorimetry(DSC), C 80 calorimeter, and thermal screening unit($TS^u$). The aim of the study was to evaluate the thermal stability of single material and mixture in esterification process. We provided the thermal data of chemical materials to present safe operating conditions through this study.

노인의 소속감, 무력감과 영양 상태와의 관계 (Relationship between Sense of Belonging, Powerlessness and Nutritional status of Elderly People)

  • 김미혜;정혜경
    • 한국식생활문화학회지
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    • 제30권1호
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    • pp.118-128
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    • 2015
  • This study was performed to analyze health problems in older adults in a comprehensive manner, including usual living habits, nutritional status, and society psychological factors. Research was conducted by a structured questionnaire by interviews with a test group of 316 people over the age of 65 from April 2012 to August 2012. Elderly people's dietary intake was assessed using NSI (Nutrition Screening Initiative) by the 24-hour retrospective method, and elderly people's feeling of helplessness and sense of belonging were assessed using the measuring device. Material analysis, descriptive statistics, and regression analysis were performed using SPSS. Elderly people with increased age showed higher chances of being in the high-risk and undernourished group. Elderly with high NSI showed low intake of fat, protein, fibrin, vitamin C, E, $B_1$, $B_2$, Niacin, K, Fe, Zn, and Cu than those with low NSI. Findings from this comparative analysis indicate that elderly with better nutritional status showed a lower feeling of helplessness than those with poor nutritional status. Overall, elderly people consumed a b road variety of foods, and social emotional stability of elderly people increased at optimal dietary levels.

재활용 현황파악을 위한 공공 자료별 국내 납 물질 흐름 상호 확인 (A Cross-check of Domestic Lead Material Flow in Public Database Sets for the Recycling Status Analysis)

  • 이상훈;김정은
    • 자원리싸이클링
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    • 제30권3호
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    • pp.63-69
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    • 2021
  • 폐기물에서의 납 회수 및 재활용을 통해 원료공급 안정화와 환경오염 예방을 동시에 도모할 수 있고 실제로도 최근 폐납축전지 위주의 재활용을 통해 납 원자재 공급 측면에서 긍정적인 효과를 보고 있다. 다만 향후 납 회수 및 재활용의 효과를 극대화하기 위해서 납의 물질 흐름의 현황을 효과적으로 파악할 필요가 있는데, 배출원 등의 복잡성과 다양성으로 인해 관련 조사가 번거로울 수 있다. 이 경우 편의상 인터넷 공개자료를 통한 예비 조사의 선수행이 효과적일 수 있다. 따라서, 본 연구에서는 공공기관 공개자료를 통해 국내 납의 흐름을 파악하여 향후 납 회수/재활용에 효율성을 기여하고자 한다. 이에 본 연구에서는 UN Comtrade와 국내 화학물질배출×이동량 사이트 자료를 이용하여 납의 수입량 및 배출×이동량을 파악하고 이를 국가통합자원관리시스템에서 제시된 납의 흐름과 비교하였다. 그 결과 폐납축전지 등 주요 항목별 관련 납의 흐름이 각 사이트 간에 대략적인 일치를 보였다.

환경규제 대응을 위한 페인트 중의 중금속 분석용 인증 표준물질 개발 (Development of Certified Reference Materials for Analysis of Heavy Metals in Paints to Cope with Environmental Regulations)

  • 유병규;선일식
    • 환경분석과 독성보건
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    • 제21권4호
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    • pp.209-219
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    • 2018
  • In the areas of RoHS, WEEE, ELV and REACH, reinforcement of environmental regulations against harmful substances is a global trend not only in EC but also in all over the world. In the fields of Korea's major export products such as material parts, electrical and electronic products and automobile parts, we are responding to these regulations consistently. To develop reference material for analyzing lead and cadmium in paints, the candidate materials were produced through the screening process which separated shapes and sizes. To secure the traceability of the candidate materials produced, the characteristics and uncertainties are estimated by ICP-AES analysis using the primary reference material. The short-term and long-term stabilities also are evaluated in parallel. In order to calculate the final certification value of the candidate material, the verification were carried out by the performance evaluation through the comparison among the KOLAS (Korea Laboratory Accreditation Scheme) laboratories, and the CRM was produced in accordance with ISO Guide 35. The certified values and uncertainties of Pb and Cd of the final paint standard, determined according to the joint analysis among laboratories, are Pb [($191.4{\pm}3.1$) mg/kg, ($944.1{\pm}5.6$) mg/kg] and Cd [($45.0{\pm}2.6$) mg/kg, ($225.5{\pm}3.5$) mg/kg]. These standard materials were developed to enhance the reliability of measurement analysis, including the validity and traceability of measurement results. Also it is expected that the CRM will be used as QCM (quality control material) for the product design and the process monitoring, so that regulation and management of hazardous heavy metals can be systematically implemented.

식물 코팅 소재 선발법과 작물들에 대한 콩 오일의 증산 억제 효과 (Screening Methods for Plant-Coating Materials and Transpiration Inhibitory Effect of Soybean Oil to Crops)

  • 정인홍;박노봉;김상열;나영은;김순일
    • 한국자원식물학회지
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    • 제27권4호
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    • pp.380-391
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    • 2014
  • 작물을 비롯한 식물체들은 작물 생산량 감소에 중요한 요인인 고온 건조풍에 의해 영향을 받는다. 이러한 영향으로부터 식물체들을 보호할 수단으로 코팅재를 고려할 수 있다. 이 연구에서 다양한 요인들에 의해 일어나는 급격한 증산작용으로부터 작물을 보호할 코팅소재를 탐색하기 위한 실내 선발법들을 확립했다. 강낭콩 유묘 포트의 무게 변화를 6일 동안 측정한 시험에서 아비온 처리구는 무처리구에 비해 유의하게 무게 감소를 억제하였다(P = 0.05). 하지만 이 방법은 장시간이 소요되는 단점이 있어 보다 단순한 방법으로 염화코발트지가 수분 접촉 시 푸른색에서 붉은색으로 변화는 색 변화법을 이용하였다. 밀납, 구아검, 유동파라핀, 콩오일 및 PE-635가 처리 30분 및 1시간 후 각각 37%와 43%의 방수력을 나타냈다. 하지만 이들 소재들도 2시간 후에는 유의할만한 방수효과를 보이지 않았다. 비록 이들 방법들이 코팅 소재를 탐색하는데 적절하다 할지라도, 보다 과학적이고 객관적인 자료들을 도출해 낼 선발법이 필요하다. 그래서 고안한 방법이 광합성측정기를 이용하여 증산율을 측정하는 방법이었다. 야외에서 재배한 보리 잎을 이용한 시험에서 2% 콩오일과 아비온 10배 희석액 처리가 증산율 억제효과를 나타냈다. 또한 옥수수 유묘 및 살구나무 신초를 이용한 시험에서 2% 유동파라핀액과 살구씨오일, 아마씨오일, 올리브오일 및 콩오일과 같은 식물체 정유들이 유의할만한 증산율 억제효과를 나타냈다(P = 0.05). 특히, 유동파라핀 및 콩오일 2%를 출수 후 2주 이상된 벼에 처리하였을 때 비슷한 증산율 억제력을 보였다. 또한 2% 콩오일과 전착제 혼합물을 옥수수 유묘에 처리 시 전착제 단독으로 처리한 것에 비해 증산율 억제효과가 증가했다. 이는 전착제가 식물체 잎 표면에서 이들 소수성 소재들이 보다 더 균일하게 확산하는데 도움을 주기 때문으로 보인다. 이 소수성 소재가 잎 표면의 기공들을 효과적으로 잘 도포하고 있음도 전자현미경으로 확인하였다. 이상의 결과는 이들 소수성 소재들이 식물체 코팅재로서 활용될 수 있음을 시사한다.