• 제목/요약/키워드: Parent Material

검색결과 183건 처리시간 0.025초

A Study on the Magnetic Properties of the Sm2Fe17Nx-type Material Produced by a Combination of HDDR Process and Nitrogenation

  • Pan, Y.R;Kwon, H.W
    • Journal of Magnetics
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    • 제3권4호
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    • pp.99-104
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    • 1998
  • The $ Sm_2Fe_{17}N_x $materials were prepared by the combination consisting of the HDDR (hydrogenation, disproportionation, desorption, and recombination) process and nitrogenation or by the conventional way consisting of nitrogenation only, and the magnetic and thermomagnetic properties of the materials were investigated. The magnetic characterisation of the prepared $ Sm_2Fe_{17}N_x $ materials was performed using a VSM. Thermal stability of the materials was evaluated using a DTA under Ar gas atmosphere. The thermomagnetic characteristics of the materials were examined using a Sucksmith-type balance. The previously HDDR-treated Sm2Fe17parent alloy was found to be nitrogenated more easily compared to the ordinary $ Sm_2Fe_{17}N_x $alloy. The $ Sm_2Fe_{17}N_x $ material produced by the combination method showed a high coercivity (12.9 kOe) even in the state of coarse particle size (around 60 ${\mu}{\textrm}{m}$). It was also revealed that the $ Sm_2Fe_{17}N_x $ material produced by the material produced by the combination showed an unusual TMA tracing featured with a low and constant magnetisation at lower temperature range and a peak just before the Curie temperature. This thermomagnetic characteristic was interpreted in terms of the competition between two counteracting effects; the decrease in magnetisation due to the thermal agitation at an elevated temperature and the increase in magnetisation resulting from the rotation of magnetisation of the fine grains comparable to a critical single domain size due to the decreased magnetocrystalline anisotropy at an elevated temperature.

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가임기 미혼여성의 월경규칙성과 정신건강 관련요인: 제5기 국민건강 영양조사를 중심으로 (Menstrual Regularity & Mental Health-related Factors on Unmarried Women of Childbearing Age: Based on the Fifth Korean National Health and Nutrition Examination Survey)

  • 최영실
    • 부모자녀건강학회지
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    • 제17권1호
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    • pp.1-7
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    • 2014
  • Purpose: The research was to identify menstrual regularity & mental health-related factors on unmarried women of childbearing age and provide a raw material in terms of setting up health policy. Methods: The KNHANE V-3 (The Fifth Korea National Health and Nutrition Examination Survey) was used and implemented through spss 18.0. Results: In general characteristics, there wasn't any remarkable difference between 20s and 30s. Looking further Mental health-related factors, stress was higher in 30s (p=.010). In 30s of irregularity mensutration women, it was accounted for 12.5% over than 3months experienced. General characteristics varied by menstrual regularity were age (p=.044), education level (p=.035) and in terms of mental health-related factors, they were stress (p=.044), sleeping time (p=.039). Multiple regression analysis was carried out to identify how influential these factors are on menstrual regularity. As a result, age, education level, sleeping time & stress was the most influence factors. Conclusion: The research had some limitations to specify and approach the feature of target in depth through KNHANE V-3. Thus, if the basic analysis regarding the menstrual problem in relation to local society was conducted on the basis of the result of research, it could help developing the promotion of health program and make the application easier.

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중학생의 흡연행위에 영향을 주는 요인 (Factors Affecting Middle School Students' Smoking Behavior)

  • 김영희;이정란;양경희
    • 지역사회간호학회지
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    • 제16권1호
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    • pp.40-48
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    • 2005
  • Purpose: This study was performed to identify the relationship between stress perceived by middle school students and social support level and to investigate the factors affecting middle school students' smoking behavior. Method: The data was collected from four hundred and thirteen students of one boys' middle school and one girls' middle school. Data were analyzed by using SPSS 11.5 Win Program. Result: Smoking rate was higher in girls than boys. The factors affecting smoking behavior were drinking (OR=67.62, P<0.01), having one parent or no parents(OR=9.98, P<0.05), and higher material support(OR=4.67, P<0.05). Conclusion: This results showed that smoking prevention program is needed for girls' middle school students. To prevent smoking, teachers should help students to cope with stress from schools and their environments with careful guidance, and organized support for the student with one parent or no parents should also be established. Furthermore, guidance in student's relationships with peers is needed regarding appropriate allowance, drinking, or substance use.

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Durability of Photocatalytic Cement after Nitric Oxide-Wet-Dry Cycling

  • Lee, Bo Yeon;Kurtis, Kimberly E.
    • 한국건축시공학회지
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    • 제14권4호
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    • pp.359-368
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    • 2014
  • Photocatalytic cement has been receiving attention due to its high oxidation power that reduces nitrogen oxide, thus contributing to a clean atmospheric environment. However, there has not yet been a thorough investigation on the effect of photocatalytic reactions on the durability of cementitious material, the parent material. In this study, photocatalytic cement samples were exposed to nitric oxide gas and UV along with cycles of wetting and drying to simulate environmental conditions. The surface of samples was characterized mechanically, chemically, and visually during the cycling. The results indicate that that the photocatalytic efficiency decreased with continued NO oxidation. The pits found from SEM indicated that chemical deterioration, such as acid attack or leaching, did occur. However, this was not confirmed by X-ray diffraction. The hardness was not affected, probably due to the formation of CSH as evidenced by the XRD pattern. In conclusion, it was found that photocatalysis could alter cementitious materials both chemically and mechanically, which could further affect long-term durability.

업셋 용접 테일러드 블랭크의 용접성 및 성형성 평가 (Evaluation of Weldability and Formability of Tailor Welded Blank by Using Upset Weld)

  • 민경복;장진호;강성수
    • 소성∙가공
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    • 제8권1호
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    • pp.57-64
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    • 1999
  • The press formability analysis of welding parts was studied in the current work by the tailor welded blank. As the body panel is used in the press forming of welding parts by a weld method of the tailor welded blank, the following conditions are demanded: 1) The strength of welding parts must be the higher than base metals. 2) After the welding, severe welding deformatins must be avoided. 3) The press formability of welding parts is similar to that of many base metals. 4) The productibility of a welding has to be higher. There are many welding methods satisfying these conditions, but the purpose of this study is to inbestigate the upset weldability and formability of the material (SPCC). SPCC steel sheet showed good weldability and formability under some welding conditions. The experimental results were discussed by the evaluation of the results obtained from tensile tests, hardness tests, micro-structures and Erichsen cup test was a little lower than that of parent material.

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친환경농산물 학교급식에 대한 만족도 및 추가 비용규모 추정 (An Analysis on the Satisfaction and Additional Cost Scale of Environmental-Friendly Agri-Product School Meal Program)

  • 이지은;허승욱
    • 한국유기농업학회지
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    • 제13권2호
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    • pp.145-159
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    • 2005
  • The objectives of this study were to analysis satisfaction and additional cost scale about environmental-friendly agri-product school meal program. To analysis satisfaction about environmental-friendly agri-product (EFAP), parent' survey were conducted residing in Cheonan city. The sample size of the survey is 304 respectively. As a result, parents of students recognized that EFAP is good for their children as well as they really want to change food material from general agri-product to EFAP. Therefore, environmental-friendly agri-policy to be more focused on consumption behavior and food security needs. In order to perfectly change food material to EFAP, about l trillion won will be additionally needed. It means that the market demand of EFAP will be dramatically increased. On the other hand, safe school meal program is one of the most important in a child's life, vital for proper growth and development.

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바이오가스 MGT 발전용 전처리시스템 재료특성 평가 (Test Evaluation of Pretreatment System Material for Bio-gas Micro Gas Turbine Power Generation)

  • 허광범;박정극;임상규;김재훈
    • 신재생에너지
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    • 제4권1호
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    • pp.37-43
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    • 2008
  • As the distributed generation becomes more reliable and economically feasible, it is expected that a higher application of the distributed generation units would be interconnected to the existing grids. This paper describes the results for the mechanical and environmental tests of pretreatment system material. Mechanical Characteristics make differences between parent / weldment, Notch existence / non-existence and air/$H_2O$ conditions. As a result, the life of pipe lines needs to maintain and fit for the operating period. Based on actual situations, the tension test of pipe welding-parts is carried out varying the exposure time of hydrogen sulfide and the fatigue resistance test is also performed inserting a notch into the pipe welding part, being exposed to the hydrogen sulfide environment for 720 hours.

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NdBaCuO 초전도박막 합성 (Fabrication of NdBaCuO Superconducting Thin Film)

  • 이상헌;이상근
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
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    • pp.244-247
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    • 2002
  • NdBaCuO thin films were prepared on $SrTiO_{3}$ substrates by RF magnetron sputtering. These as-grown films were classified into 3type. The resistivity of the deposited films are usually lower than of the YBCO film. The Tc (onset) and Tc (R=0) in the optimized thin films are as high as 90 and 80K, respectively. These as-grown films are highly uniform and semi-trans parent and have a room temperature resistivity of $0.3m{\Omega}cm$.

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A new ALE formulation for sloshing analysis

  • Aquelet, N.;Souli, M.;Gabrys, J.;Olovson, L.
    • Structural Engineering and Mechanics
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    • 제16권4호
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    • pp.423-440
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    • 2003
  • Arbitrary Lagrangian Eulerian finite element methods gain interest for the capability to control mesh geometry independently from material geometry, the ALE methods are used to create a new undistorted mesh for the fluid domain. In this paper we use the ALE technique to solve fuel slosh problem. Fuel slosh is an important design consideration not only for the fuel tank, but also for the structure supporting the fuel tank. "Fuel slosh" can be generated by many ways: abrupt changes in acceleration (braking), as well as abrupt changes in direction (highway exit-ramp). Repetitive motion can also be involved if a "sloshing resonance" is generated. These sloshing events can in turn affect the overall performance of the parent structure. A finite element analysis method has been developed to analyze this complex event. A new ALE formulation for the fluid mesh has been developed to keep the fluid mesh integrity during the motion of the tank. This paper explains the analysis capabilities on a technical level. Following the explanation, the analysis capabilities are validated against theoretical using potential flow for calculating fuel slosh frequency.

무의식의 창조성 관점으로 고찰한 창조신화: 흑암/혼돈, 천지개벽/분리, 섬/육지 창조 중심 (Psychological Meaning of Creation Myths: Focused on Darkness/Massa Confusa, Separation of World Parent and Creation of Land/Island)

  • 김진숙
    • 심성연구
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    • 제38권2호
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    • pp.269-304
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    • 2023
  • 본 논문의 취지는 창조신화에 보편적으로 나타나는 흑암/혼돈 천지개벽/분리, 육지/산 창조 관련 신화의 심리학적 의미를 임상현장에서 관찰한 꿈, 적극적 상상 및 예술작업과 연관하여 무의식의 창조성과 치유적인 기능을 드러내는 것에 있다. 먼저 창조신화가 개인사나 인류사에서 혼돈에서 새로운 질서를 필요로 할 때 무의식의 창조성에 의하여 저절로 만들어지는 원형적인 투사 현상으로서 자아의 태도에 따라 새로운 의식의 도약(재건)의 조짐이 될 수도 있고 자아의식의 침범이 될 수 있음을 논하고, 융, 폰 프란츠, 노이만, 하딩, 에딘져 및 국내의 연구현황과 연구자의 선행연구를 소개하면서 사례를 연관시켜서 연구하게 된 배경을 밝힌다. 창조신화의 흑암/원초적인 혼돈(massa confusa)'의 심리학적 의미에서 '흑암'은 어두워서 보지 못하는 무의식 상태로 보고 어둠속에서 기어다니는 에스키모의 창조자와 어둠속에 있거나 보는 것에 문제가 있는 꿈들과 상황을 소개하면서 연금술의 니그레도(nigredo)공정과 연관하였다. '원초적인 혼돈'은 하나 속에 모든 것이 들어있는 우로보로스, 플레로마, 유아기의 경험 또는 근원적인 자궁의 의미를 가지며 창조의 전조이기도 하지만 심연(abyss)에 갇힌 경험이 될 수 있다는 점을 관련된다고 보는 꿈과 상황을 함께 논한다. '천지개벽(분리)'은 무의식적인 내용이 의식이 되기 전에 의식의 문턱을 건드릴 때 두 개로 쪼개지는 것과 관련되고 의식의 진보가 있을 때 나타난다고 보면서 관련신화로서 '천지에 간극이 생겨서 만들어지는 세상', '천상의 존재가 지상으로 내려와 만들어지는 세상', '산 이동 설화'를 소개하고 각 신화가 가지는 심리학적 의미를 관련 사례와 함께 논한다. 관련문헌을 토대로 천지분리가 자체적으로 일어난다는 것과 창조자의 외로움, 불안함 등 정서적인 부분이 개입한다는 것, 그리고 지연된 분리가 크레아투라(creatur 창조물)의 죽음이 되고 성급한 분리가 천재 혼돈의 죽음이 된다는 것이 임상에서 시사하는 바를 논한다. '천지개벽'을 연금술의 분리(separatio)공정과 연관하면서 흑암/혼돈/무의식에서 빛/의식성을 획득해 가는 과정과 동일하다고 보았다. '육지 창조'는 무의식의 내용물이 자아의 영역으로 구체화되는 의식성의 출현을 의미하며. 관련 신화로서 메르쿠리우스 영의 육화라고 볼 수 있는 '괴물/거신의 몸이 육지가 되는 신화', '흙을 가지고 오는 등 창조자의 부단한 노력으로 만들어지는 육지'와 '저절로 만들어지는 육지'에 관련되는 신화와 관련 사례를 소개한다. '육지 창조'를 연금술의 땅처럼 구체화되는 응고(coagulatio)와 연관시키면서 적극적 상상 및 미술, 음악, 무용 등의 창조적인 작업이 추상적이라고 할 수 있는 심상을 자아영역으로 구체화한다는 점에서 무의식의 치유적 기능을 허용 내지 활성화하는 방편이 될 수 있다는 점을 부각한다. 마지막으로 세계멸망 후 다시 떠오른 육지관련 신화를 '자아의 재구축'의 의미로 보고 관련 임상 자료를 소개하면서 분석가/치료사/임상감독자의 무의식이 임상에 미치는 영향을 보여주는 것으로 마감한다.