• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.323-326
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• 2001

NI$_2$MnGa-based ferromagnetic shape memory alloys (FSMA) are hoped to be used as robust actuators with high performance and power density, as a replacement of other actuation materials such as thermo-mechanical SMAs and mechanical-electric piezoelectrics. Recently, we have observed significant shape changes under magnetic field application when single- and poly-crystalline forms are used. In the present study, two mechanisms have been proposed to predict the magnetic field-induced shape change as a function of external magnetic field at temperatures below Mr and above Ar. In the case of the field-induced shape change at temperature below M$_{f}$, paired martensite variants are assumed to form by application of magnetic field. The direction of magnetization in martensites formed in austenite matrix is assumed to be parallel to the applied magnetic field in the case of shape change by application at temperature above Af. Various energies has been considered in the shape change under two mechanisms.s.

• 지역연구
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• 제10권1호
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• pp.19-37
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• 1994

The past studies on the change of industrial location can be reinterpreted as spatial determinism, decision making process determinism and industrial sturcure determinism according to the view of the mutual operation between the economic activity and spatial structure. From the point of the industrial structure determinism which focuses on the fact that the locational type of production activity can be differenciated by the structural change of industry itself, it is proper to explain the change of industrial location not only by spatial condition but also by containing the fundamental changing causes for the reorganization of the spatial condition. One of the most important changing causes for reorganizing economic space is industrial technology. This study aims to explain the spatialization process of industrial technology and consists of the process of suggesting the hypothesis that the spatialization process is differentiated according to the production organization as the user of industrial technology and the user of industrial technology and the production system as using method. In other words, this study attempts to internalize the technology variable, which has been treated as external in the past studies on the industrial location, as an independent one and consider the production organization and production system as a paramenter, so that it can represent 'conceptual framework' for explaining the change of industrial location.

• 센서학회지
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• 제19권3호
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• pp.214-220
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• 2010

Three-dimensional(3D) structure of specific DNA can be changed between two conformations under an external environmental transition such as pH and salt concentration variations. We have experimentally observed the conformational transitions of i-motif DNA using AFM cantilever bioassay. It is shown that pH change of a solvent induces the bending defleciton change of a cantilever functionalized by i-motif DNA. This indicates that cantilever bioassay enables the label-free detection of DNA structural changes upon pH change. It is implied that cantilever bioassay can be a de novo route to quantitatively understand the conformational transitions of biological molecules under environmental changes.

• 대한건축학회논문집:계획계
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• 제34권10호
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• pp.107-118
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• 2018

Cedric price is an architect and educator who have had an influence on architectural thinking through teaching and projects, rather than completed buildings. The purpose of this study was to analyze the architecture of Cedric Price in terms of time. Time was an important factor to understand his architecture along with his interest in technology, so most of his architectural thinking and methodology - anti-architecture, programmatic indeterminacy, a philosophy of enabling and so on, could be explained under the consideration of time. Depending on how he considered and used the concept of time, his projects could be categorized into two groups; The first group was related to the change over time, and this group again divided into three sub categories; change of user's preference, change of external environment, and change over building lifetime. The second group was related to planning of time, which could be divided again into two categories; programmatic planning and the usage planning during the period. This categorization could provide a frame to look into his architecture, through which his projects showed the limitation in modern architecture and the possibility for contemporary architecture.

• Journal of Information Processing Systems
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• 제19권2호
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• pp.149-163
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• 2023

Affected by external factors, errors in time series data collected by sensors are common. Using the traditional method of constraining the speed change rate to clean the errors can get good performance. However, they are only limited to the data of stable changing speed because of fixed constraint rules. Actually, data with uneven changing speed is common in practice. To solve this problem, an online cleaning algorithm for time series data based on dynamic speed change rate constraints is proposed in this paper. Since time series data usually changes periodically, we use the extreme learning machine to learn the law of speed changes from past data and predict the speed ranges that change over time to detect the data. In order to realize online data repair, a dual-window mechanism is proposed to transform the global optimal into the local optimal, and the traditional minimum change principle and median theorem are applied in the selection of the repair strategy. Aiming at the problem that the repair method based on the minimum change principle cannot correct consecutive abnormal points, through quantitative analysis, it is believed that the repair strategy should be the boundary of the repair candidate set. The experimental results obtained on the dataset show that the method proposed in this paper can get a better repair effect.

• 대기
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• 제19권1호
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• pp.53-66
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• 2009

The purpose of this study is to describe the roles of carbon dioxide in the climate change, and carbon dioxide reduction policies in some countries. In addition, ways to cope with climate change in Korea are also discussed. Currently, global temperatures are rising due to the carbon dioxide produced by human beings. Global temperatures will rise approximately $6^{\circ}C$ until 2100 if we emit carbon dioxide at a present rate. Temperature rise will affect the terrestrial and oceanic resources, and ultimately influence the socio-economic structures including political stability. Most of the carbon dioxide comes from fossil fuels. Therefore, it is urgent to reduce the use of energy, which comes from fossil fuels. Solving the climate change due to the increases in carbon dioxide is a global problem. Korea should participate in the international community and cooperate with each other in order to reduce the carbon dioxide concentration. No policy was announced for the reduction of carbon dioxide so far. Korea should make a policy for the reduction of carbon dioxide in a specific year compared to that of certain standard year such as 1990 or 2005. Making policy should be based on the scientific result of the amount of carbon dioxide emitted and absorbed. Germanwatch announced the Climate Change Performance Index (CCPI) in order to evaluate an effort to reduce the carbon dioxide for 56 countries which emits 90 % of global carbon dioxide. Ranking for Korea is 51 among 56 countries. This clearly indicates that the appropriate carbon dioxide reduction has not been exercised yet in Korea. Researchers have a moral responsibility to provide updated new ideas and knowledges regarding climate change. Politicians should have a sharp insight to judge the ideas provided by researchers. People need an ethics to reduce the carbon dioxide in every day's life. Scientific research should not be influenced by stress caused by external budget and negative impact of capitalism. Science should be based on the pure curiosity.

• 한국방사선학회논문지
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• 제6권4호
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• pp.299-303
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• 2012

자기공명 관절 조영술(Shoulder MR Arthrography)는 견관절(Shoulder joint) 의 복잡한 해부학적 구조에 관하여 정확한 영상평가를 진단하기 위해 시행 한다. 우리는 어께 상완골(Shoulder humerus) 의 다양한 position인 Neutral position, Internal rotation position, External rotation position 에 관하여 Shoulder joint의 해부학 적인 회전 변화가 견관절 자기공명(Shoulder MRI) 영상에 어떤 진단적 결과를 가져오는가에 대해 상호 비교 하였다. 또한 환자의 정확한 촬영자세 유지를 위해 촬영 보조기구를 만들었다. 이 보조기구는 Modeling 설계에 의해 우리가 직접 제작한 자기공명 견관절 조영술 보조 기구이다. 이 보조기구를 사용하여 촬영한 결과 다음과 같은 결론을 도출해 내었다. External rotation position 에 의한 Shoulder MRArthrography 검사가 Shoulder joint의 중요 해부학적 구조인 Biceps tendon, Supera-spiatus tendon, Sub-scapularis tendon, Labrum, Sub-acromial space 의 해부학적 평가에서 제일 적합하다는 진단적 평가를 얻었다.

• Journal of Radiation Protection and Research
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• 제38권3호
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• pp.157-165
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• 2013

To determine the factors affecting the external radiation dose rates of patients undergoing PET-MRI examinations and to assess the trends of these differences, we measured the changes in the dose rates of $^{18}F$-FDG during a set period of time for each body region. Consistent with theoretical predictions, the dose rate decreased over time in patients undergoing PET-MRI examinations. Furthermore, immediately after the $^{18}F$-FDG injection, the dose rate in the chest region was the highest, followed by the abdominal region, the head region, and the foot region. The dose rate decreased drastically as time passed, by 2.47-fold, from $339.23{\pm}74.70mSv\;h^{-1}$ ($6.73{\pm}5.79$ min) at the time point immediately after the $^{18}F$-FDG injection to $102.71{\pm}26.17mSv\;h^{-1}$ ($136.11{\pm}25.64$ min) after the examination. In the foot region, there were no significant changes over time, from $32.05{\pm}20.23mSv\;h^{-1}$ ($6.73{\pm}5.79$ min) at the time point immediately after the $^{18}F$-FDG injection, to $23.89{\pm}9.14mSv\;h^{-1}$ ($136.11{\pm}25.64$ min) after the examination. The dose rate is dependent on the individual characteristics of the patient, and differed depending on the body region and time point. However, the dose rates were higher in patients who had a lower body weight, shorter stature, fewer urinations, lower fluid intake, and history of diabetes mellitus. To decrease radiation exposure, it is difficult or impossible to change factors inherent to the patient, such as sex, age, height, body weight, obesity, and history of diabetes mellitus. However, factors which can be changed, such as the $^{18}F$-FDG dose, fasting time, fluid intake, number of urinations, and contrast agent dose can be controlled to minimize the external radiation exposure of the patient.

• 대한본초학회지
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• 제31권4호
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• pp.79-85
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• 2016

Objectives : The aim of this study is to investigate anti-atopic dermatitis effect using ato-tang.Methods : Ato-tang was external treatment to NC/Nga mice for 4 weeks, where atopic dermatitis was induced by DNCB at 1% and 0.4% for 3 weeks. Atopic dermatitis index score was measured using eye observation and picture evaluation. The histopathological change of dorsal skin was observed by hematoxylin and eosin (H&E) staining. Cytokines including IL-4, IL-5 and IL-13 were measured by Luminex or reverse transcriptase polymerase chain reaction (RT-PCR) analysis and immunoglobulin E (IgE) was measured by ELISA reader.Results : The dorsal skin of Ato-tang group showed decrease in erythema, pruritus, dry skin, edema, excoriation, erosion and lichenification level through naked eye observations. Immunoglobulin cell infiltration and the thickness of epidermis were significantly decreased in the dorsal skin compared to control. Production of Th2 cytokines (IL-4, IL-5, IL-13) and IgE level in serum were all significantly decreased, in comparison with control. In addition, mRNA expression level of Th2 cytokines (IL-4, IL-5, IL-13) in spleen was decreased, in comparison with control.Conclusion : The results indicated that external treatment of ato was improved skin barrier function in the symptoms of atopic dermatitis disease. Also, atopic dermatitis factors where cytokine as well as immunoglobulin E in serum and mRNA expression were decreased, respectively, in comparison with control. Therefore, we suggest that ato could be effectively used as a external therapeutic drug based on atopic dermatitis factors.

• 한국항공우주학회지
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• 제40권7호
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• pp.616-622
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• 2012

본 논문에서는 센터 파일론에 150갤런 외부 연료 탱크를 장착한 전투기의 전술기동 중 섬광탄 운용의 문제점을 검토하고 운용 가능한 방안을 제시하였다. 섬광탄 발사시 투하 궤적 및 외부 연료 탱크 수평 핀의 손상 범위를 풍동실험과 수치해석을 통해 분석하였다. 핀의 손상을 방지하기 위한 방안으로 1) 섬광탄 발사 각도를 조정하는 방안과 2) 핀의 형상을 변경하는 방안을 비교 검토 및 실용성을 분석한 결과 핀을 재설계하는 방안이 채택되었다. 풍동실험을 통하여 재설계한 수평 핀을 장착한 외부 연료 탱크의 투하 안전성을 평가하였다.