• Title/Summary/Keyword: NEG

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NEG를 주 펌프로 하는 스테인레스강 극고진공 시스템

  • Ha, Tae-Gyun;Gwon, Hyeok-Chae;Kim, Se-Hyeon;Park, Jong-Do
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.139.1-139.1
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    • 2014
  • 구연산 전처리 후 진공 중 산화처리를 한 스테인레스강 진공용기에 비증발성 게터(NEG)와 스퍼터 이온펌프의 조합을 사용하여 낮은 10의 -12 mbar의 극고진공에 도달하였다. 실험에 사용된 진공용기의 기체방출률은 기존의 일반 스테인레스강 진공용기에 비해 15배 이상 낮은 것으로 측정되었다. 극고진공에 도달하기 위해 수소에 대한 배기속도가 높은 NEG 펌프를 주 펌프로 사용하였으며 스퍼터 이온펌프는 NEG가 배기하지 못하는 무극성 또는 불활성 기체를 배기하는 보조펌프로 작용하도록 하였다.

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Fabrication and Vacuum Performance Test of the NEG Pump for $10^{-9}$ Pa Chamber ($10^{-9}$ Pa대 용기를 위한 NEG 펌프 제작 및 진공성능 조사)

  • 박미영;인상렬
    • Journal of the Korean Vacuum Society
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    • v.10 no.3
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    • pp.312-320
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    • 2001
  • A Non-Evaporable Getter(NEG) pump was fabricated using Zr-V-Fe alloy modules to obtain $10^{-9}$ Pa range pressures. Pumping performances and activation characteristics were investigated and the pumping speeds for hydrogen, deuterium and carbon monoxide gases of the NEG pump were measured. And hydrogen desorption characteristics were examined during activation at $450^{\circ}C$. Futhermore the vacuum performance was compared with those of other high vacuum pumps as turbo-molecular pump, sputter-ion pump, and cryo pump by analyzing the residual gases of the system.

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Distributed pumping using pill NEG

  • Park, Jong-Do
    • Proceedings of the Korean Vacuum Society Conference
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    • 2015.08a
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    • pp.69.2-69.2
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    • 2015
  • 가속기의 진공용기는 안지름이 대략 20~40 mm 정도로 아주 작지만 길이는 수백 미터 이상이다. 이 같은 진공장치에서 기체 컨덕턴스가 그 진공성능을 결정하게 되며 점점 더 작아지고 있다. 이때 진공배기 방법은 주로 균등배기(distributed pumping)을 하는 데 초기에는 distributed ion pump와 Strip NEG를 주로 사용하였으며 최근에는 coated NEG가 대세이다. 균등배기의 또 다른 한 가지 방법으로 작은 동전 모양의 게터를 사용하여 그 성능을 평가하여 보고하고자 한다.

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The Kinetic Analysis of the Lower Extremity Joints when Performing Uchi-mata by Uke's Posture in Judo (유도 허벅다리걸기 기술 발휘 시 받기 자세에 따른 하지관절의 kinetic 분석)

  • Yoon, Hyun
    • Korean Journal of Applied Biomechanics
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    • v.15 no.2
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    • pp.167-183
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    • 2005
  • The purpose of this study was to analyze the kinetical variables of the lower extremity joints when performing uchimata(inner thigh reaping throw) by uke(receiver)'s two posture(shizenhon tai), jigohon tai), by voluntary resistance level(VRL) in judo. The subjects, who were for 3 male Korean national representative judokas(elite group : EG) and 3 male representative judokas of Korean University(non-elite group: NEG), and were filmed 4 DV video cameras(60fields/sec.), that posture of uke were shizenhon-tai (straight natural posture), jigohon-tai(straight defensive posture), VRL of uke was 0%. The selected trials were subject to 3-dimensional film motion analysis and ground reaction force(MRF) analysis. The kinetical variable of this study were temporal, postures( ankle and knee angle of attacking leg), that were computed through video film analysis, MRF at events were obtained from the ground-reaction force analysis by AMTI force plate system. When performing uchi-mata according to each posture and by VRL, from the data analysis and discussion, the conclusions were as follows : 1) Temporal variables : total time-required(TR) when performing uchi-mata was shown EG 0.13sec the shorter than NEG(o.77sec.) in shizenhon-tai. and EG 0.17sec the shorter than NEG(o.76sec.) in jigonhon-tai. Also, all of two groups' jigohon-tai(0.68sec.) were faster than shizenhon-tai(0.71 sec.). 2) The posture variables : The angle of ankle in attacking when performing were plantar flexion in EG, and dorsi flexion in NEG by shizenhon-tai and jigohon-tai posture. The angle of knee in attacking when performing were extension in EG and NEG, but range of extension in EG were larger than in NEG. 3) MRF : Vertical MRF when performing uchi-mata was shown the strongest in the 2nd stage of kake phase(2.23BW) by EG in both posture, and it was same value by NEG(2.23BW), but shizenhon-tai (2.28BW), jigohon-tai(1.64BW), respectively.

$10^{-10}$ Pa 영역에서의 스퍼터 이온펌프와 Non-Evaporable Getter (NEG) 펌프조합의 배기 특성

  • Jo, Bok-Rae;Han, Cheol-Su;Kim, Yeong-Jun;An, Sang-Jeong
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.148-148
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    • 2013
  • 스퍼터 이온펌프(Sputter Ion Pump)는 주로 화학흡착으로 동작하며 기계적 진동이 없고, 기름 등의 오염 물질을 배출하지 않으며, 수명이 길어 초고청정 진공이 요구되는 표면실험장치, 표면분석계, 입자가속기 등에서 널리 사용 되고 있다. 일정한 지름을 갖는 다수의 원통 양극과 그 양단에 두개의 음극판을 배치시킨 후, 양극과 음극 사이에 수 kV의 전압을 걸고 원통의 축방향으로 자장을 인가하면 페닝 방전이 발생한다. 냉음극에서 방출된 전자는 양극으로 비행하면서 가스를 이온화한다. 이온분자는 가스흡수성 게터재료로 된 음극에 충돌하여 스퍼터링을 일으키며 게터막를 주변에 증착시킨다. 이온 및 중성 가스는 게터 고체막 속에 주입 포획되는 형태로 배기된다. 스퍼터 이온펌프는 $10^{-5}$ Pa 부근에서 최대 배기속도를 가지며, 압력이 낮아질 수록, 특히 $10^{-10}$ Pa영역 이하에서는 그 배기속도가 급격히 저하되며, $10^{-10}$ Pa영역에서는 배기능력을 거의 상실한다. 따라서 스퍼터 이온펌프 단독으로 진공시스템을 배기할 때 도달압력은 $10^{-9}$ Pa 영역에 머무르게 되며, $10^{-10}$ Pa 이하의 극고진공을 얻기 위해서는, $10^{-8}$ Pa 이하의 압력에서 배기 속도가 압력과 무관한 흡착펌프(getter pump)와 이온펌프를 조합하여 사용한다. 본 실험에서는 $600^{\circ}C$ 이상의 온도로 진공로에서 탈개스시킨 진공용기를 배기속도 450, 60, 30, 20, 5, 3 l/s의 6종류의 이온펌프와 배기속도 400 l/s, 100 l/s의 non-evaporable getter (NEG) 펌프를 조합시켜 배기하여 그 배기 특성을 비교하였다. 도달 압력은 이온펌프의 배기속도가 클수록 낮아지는 경향을 보여주었다. 450 l/s 이온펌프와 400 l/s NEG를 조합하여 배기시킬 때 도달 압력은 ~$2{\times}10^{-10}$ Pa을 기록하여 가장 낮았으며, 3 l/s 이온펌프와 400 l/s NEG를 조합하였을 때는 $ 2{\sim}3{\times}10^{-8}$ Pa을 기록하였다. 450 l/s 이온펌프와 400 l/s NEG를 조합한 경우 잔류가스의 대부분이 수소였으나, 3 l/s 이온펌프와 400 l/s NEG의 조합한 경우에는 메탄의 잔류량이 수소 보다 많았다. 이 결과는 메탄을 배기하지 못하는 NEG의 배기 특성을 보완하기 위해서는 일정 배기속도 이상의 이온 펌프가 필요함을 보여준다.

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The Effect of Mother's Routine Exercise on Exercise Regularity, Obesity Indices, Psychosocial Well-being Index and Nutrient Intake in Her Daughter (어머니의 운동이 여대생 딸의 운동, 비만지표, 사회심리적 건강지수 및 영양소 섭취에 미치는 영향)

  • Cho, Kang-Ok;Kim, Yeun-Soo
    • The Korean Journal of Community Living Science
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    • v.19 no.2
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    • pp.191-199
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    • 2008
  • The purpose of this study was to obtain an understanding of the effect of regular exercise on obesity indices, the psychosocial wellbeing index, dietary factors and exercise regularity among 146 healthy mothers and 146 their daughters. "Mother" subjects were divided into two groups classified as regular exercise group(REG) and none exercise group(NEG). The exercise regularity of REG's daughters(30.8%) and of NEG's daughters (2.0%) was significantly different(p<0.001). The Obesity Indices(Body Mass Index (BMI), Waist Hip Ratio(WHR) and Percentage of Ideal Body Weight(PIBW)) of NEG's daughters were significantly higher than those of REG's daughters(p<0.001). But the psychosocial wellbeing index was not significantly different between REG's daughters and NEG's daughters. Intake of total energy, protein, fat, Ca, niacin and Fe were significantly different(p<0.001) between REG's daughters and NEG's daughters. Especially, vitamin C intake of REG's daughters was significantly higher than that of NEG's daughters(p<0.001). The exercise regularity of mothers was mainly related with Obesity Indices and nutrient intake in their daughters. Therefore, it might be necessary to maintain exercise regularity to prevent obesity and diet related problems in mothers and their daughters.

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Effects of Sowing Date and Cutting Time on Feed Value of Rye in Paddy Field (파종기와 예취시기가 답리작 호밀의 동료가치에 미치는 영향)

  • ;Je-Cheon Chae
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.39 no.6
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    • pp.519-525
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    • 1994
  • This experiment was conducted to investigate the effects of sowing date and cutting time on feed value of rye in paddy field at Yesan from Oct. 1990 to June 1991. The field experiment was sown 5 times at 10 day intervals from Oct. 5. The content of crude protein, digestible protein, total digestible nutrient(TDN), minerals(P, K, Ca, Mg), and energy(ENE, NEL, NEM, NEG) were decreased due to earlier sowing, while the content of acid detergent fiber (ADF) and neutral detergent fiber(NDF) increased. On the other hand, the yields per unit area for crude and digestible protein, TDN, minerals, and energy increased due to earlier sowing, but there was no significant difference among the plots sown on Oct. 5 through Oct. 25. The highest yield of crude protein was shown at late flowering stage, digestible protein and net energy gain (NEG) at heading stage and TDN at milk stage respectively.

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Mixed rare earth $(Nd_{1/3}Eu_{1/3}Gd_{1/3})Ba_2Cu_3O_{7-d}$ thin films by PLD (PLD법에 의한 혼합된 희토류계$(Nd_{1/3}Eu_{1/3}Gd_{1/3})Ba_2Cu_3O_{7-x}$ 고온 초전도 박막)

  • Ko, Rock-Kil;Bae, Sung-Hwan;Jung, Myung-Jin;Jang, Se-Hoon;Song, Kyu-Jeong;Park, Chan;Sohn, Myung-Hwan;Kang, Suk-Ill;Oh, Sang-Soo;Ha, Dong-Woo;Ha, Hong-Soo;Kim, Ho-Sup;Kim, Young-Cheol
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.05a
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    • pp.3-3
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    • 2009
  • In order to investigate the possibility of using mixed rare earth $(Nd_{1/3}Eu_{1/3}Gd_{1/3})Ba_2Cu_3O_{7-x}$ (NEG123) as the superconducting layer of the HTS coated conductor, the NEG123 thin film was deposited epitaxialy on LAO(100) single crystal and IBAD_YSZ metal templates by pulsed laser deposition. Systematic studies were carried out to investigate the influences of deposition parameters of PLD on the micro structure, texture and superconducting properties of NEG-123 coated conductor. Deposition at oxygen partial pressure of 600 mTorr was needed to routinely obtain high quality NEG123 films with $J_c$'s (77K) over 2 MA/$cm^2$ and Tc's over 90K (${\Delta}T{\sim}2\;K$). We verified from magnetization study that the NEG123 has an improved in-field Jc as the field increases at temperatures between 10 K and 77 K compared with Gd123. The $J_c$ (77K, self field) and the value of onset $T_c$ of NEG123 thin film on LAO substrate was $4.0MA/cm^2$ and 92K, respectively. This is the first report, to the best of our knowledge, of coated conductors with NEG123 film as the superconducting layer which have Ic and Jc over 40 A/cm-width and 1.6 MA/$cm^2$ at 77K, self field. This study shows the possibility of using NEG123 film as the superconducting layer of the HTS coated conductor which can be used in high magnetic field power electric devices.

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Determination of Net Energy and Protein Requirements for Growth in Hanwoo Steers by Comparative Slaughter Experiment (비교도체법에 의한 한우 거세우의 증체에너지 및 단백질 요구량)

  • Kim, K.H.;Oh, Y.G.;Lee, S.C.;Shin, K.J.;Chung, W.T.;Kang, S.W.;Hong, S.K.;Ju, J.C.;Baek, B.H.
    • Journal of Animal Science and Technology
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    • v.49 no.1
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    • pp.41-50
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    • 2007
  • Data from a comparative slaughter experiment with two hundreds of Korean native (Hanwoo) beef steers were utilized to determine net energy and protein requirements for growth (NEg and NPg). Eight randomly selected steers were used in the initial slaughter group of 6 month of age and the remaining steers allocated to treatments within two groups. The restricted groups were fed 1.2 to 1.5% concentrate per kg body weight (BW) in the growing period (6~12 month of age), 1.7 to 1.8% concentrate per kg BW in the early fattening period (13~18 month of age), and concentrate feed ad libitum in the late fattening period (19~30 month of age). Ad libitum groups were fed concentrate ad libitum through the whole period. Rice straw was offered ad libitum for 24 month of two feeding systems. The steers were slaughtered when animals reached every 2 month from 8 to 30 month of age. For all body composition determinations, whole empty body components were weighed, taken each proportional subsample was ground for chemical analysis. Equations developed with the pooled data to predicted NEg and NPg were similar to the equations of Japanese Feeding Standard for Beef Cattle (2000). First equations were developed to predicted NEg; NEg = 0.05332×LBW0.75×DG for restricted treatment and NEg = 0.04912×LBW0.75×DG for ad libitum treatment. Second equations were developed to predicted NPg; NPg = DG × (224.7-0.251×LBW) for restricted treatment and NPg=DG×(210.1-0.214×LBW) for ad libitum treatment.

Night Eating Habits of Middle School Students in Gyeonggi (경기 일부지역 중학생의 야식 섭취실태)

  • Cho, Yu-Jin;Kim, Mi-Hyun;Kim, Myung-Hee;Choi, Mi-Kyeong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.2
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    • pp.300-308
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    • 2014
  • The purpose of this study was to investigate the night eating habits of middle schoolers. A total of 705 middle school students residing in Gyeonggi were surveyed about their dietary habits related to night eating. Among the total subjects, 59.9% (n=422) had night eating more than once a week and were classified into a night eating group (NEG). The main reason for night eating was hunger (79.1% of NEG) and the highest proportion of night eating was related to food purchased by family (39.3% of NEG). Most of the NEG had night eating in their home with family members, and the time with highest frequency of night eating was between 10 p.m. and 11 p.m.. About 33% of the NEG went to bed within an hour after night eating and 69.2% of the NEG did not report any change after night eating. The most common factors considered when choosing a night eating menu, in order of frequency, were taste, hygiene, and amount. The favorite items on the night eating menu were frozen desserts, fresh fruits, chicken, fruit juice, Ramen, pizza, and Jajangmyeon. The most frequent menu choices were fresh fruits, frozen desserts, Ramen, chicken, yogurt, and fruit juice. The NEG had higher scores for picky eating (P<0.01), overeating (P<0.01), salty eating (P<0.01), and irregular meal times (P<0.001) compared to the non-NEG. Consequently, the NEG had more dietary problems than the non-NEG and their night eating behaviors were related to family habits. Night eating was mainly dominated by a diet of carbohydrates and fats, and the intake frequency and preference for foods with low nutritional value were high; thus, a practical and systematical nutrition education is required. Seasonal and comparative studies on night eating status according to various times and amounts of night eating are also required.