• 제목/요약/키워드: thought of change

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원거리 플라즈마 화학기상증착법을 사용하여 증착한 비정질 탄화규소 막의 증착조건에 따른 특성 및 증착 균일도 변화 (The Properties and Uniformity Change of Amorphous SiC:H Film Deposited using Remote PECVD System with Various Deposition Conditions)

  • 조성혁;최유열;최두진
    • 한국세라믹학회지
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    • 제47권3호
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    • pp.262-267
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    • 2010
  • a-SiC has been thought as an ideal candidate for conventional silicon at many applications. However, the uniformity problem of deposition has been a obstacle for conventional use of a-SiC:H films. a-SiC:H films were deposited on (100) silicon wafer by RPECVD system in various temperature. HMDS and $H_2$ gas were used as a precursor and a carrier gas, respectively. The flow rate of HMDS source and $C_2H_2$ dilution gas was fixed in order to study the carbon effect on the film stoichiometric and bonding properties. The plasma power varied from 200 to 400W. We used three types of source delivery line to control the uniformity and film properties of deposited film. We showed that the change of source delivery line has effect on the film uniformity of deposited film and this change of line did not affect on film properties. Also, the change of deposition conditions has effect on the film uniformity.

Better Management (Risk and Change) through NEC Contracts in Hong Kong

  • TUNG, Chu Hoi;MEMON, Shoeb Ahmed;JAVED, Arshad Ali
    • 국제학술발표논문집
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    • The 8th International Conference on Construction Engineering and Project Management
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    • pp.323-330
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    • 2020
  • Project delays, cost overruns, and disputes are becoming a norm for the construction industry in Hong Kong. Researchers argue that the inability of traditional contracts to manage risk and associated changes are perhaps the main points of contention. The Institution of Civil Engineers published a new engineering contract (NEC), NEC4 Suite of Contracts in this to facilitate better risk management through collaborative culture in construction projects. NEC aims to increase the chances of project success thought its flexible nature of contracts, 'simple' and 'clearly written' documents and provision for the incentive by adopting a better management approach. This paper focuses on traditional and NEC contracts to compare risk management and change management aspects. Through literature review and preliminary interviews with three industry professionals, the paper is exploring how a change in traditional contracts can recuperate from disaster. Our interviewees in this work have extensive experience in traditional as well as in NEC contracts. The results suggest a proactive risk management provisions in NEC contracts does make a difference to avoid later escalation of issues. Whereas, management of change helps streamline all identified issues through a structured process without going in mediation or litigation. NEC, with its new approach to collaborative working, allows partners to be vigilant, yet gratifying in the project process.

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반용융 재료의 물성치 평가에 관한 연구(II) -모델재료의 후방압출 실험과 상계해석을 통한 반용융 재료의 유동응력식 결정- (A Study on Material Characterization of Semi-Solid Materials(II) -Determination of Flow Stress For Semi-Solid Materials Using Backward Extrusion Experiment with Model Material and Upper Bound Analysis-)

  • 이주영;김낙수
    • 소성∙가공
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    • 제8권4호
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    • pp.374-383
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    • 1999
  • To determine the flow stress of semi-solid materials, a new combined method has been studied by experimental and analytic technique in the current approach. Using backward extrusion experiment and its numerical analysis, the characterization scheme of semi-solid materials according to the change of initial solid volume fraction has been proposed. Because that solid volume fraction is sensitive to temperature change, it is required to precisely control the temperature setting. Model materials can guarantee the establishment of material characterization technique from the noise due to temperature change. Thus, clay mixed with bonded abrasives was used for experiment and the change of initial solid fraction was copied out through the variation of mixing ratio. Upper bound method was adapted to increase in efficiency of the calculation in numerical analysis and new kinematically admissible velocity field was employed to improve the accuracy of numerical solution. It is thought that the material characterization scheme proposed in this study can be applied to not only semi-solid materials, but also other materials that is difficult to obtain the simple stress state.

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자외선 차단제가 악안면 실리콘의 색변화에 미치는 영향에 관한 연구 (A STUDY ON THE EFFECT OF UV LIGHT ABSORBER ON THE COLOR CHANCE OF MAXILLOFACIAL SILICONE)

  • 송윤석;임주환;조인호
    • 대한치과보철학회지
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    • 제37권3호
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    • pp.343-357
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    • 1999
  • The color change of maxillofacial silicone has been attributed to certain environmental factors such as exposure to the UV component of natural sunlight, wetting and drying of the elastomer and surface abrasion resulting from the application and removal of cosmetics. The purpose of this study was to evaluate the color change of maxillofacial silicone (Silastic MDX4-4210) according to type of pigment (cadmium yellow, titanium white, cosmetic red), and UV absorber application method after 200, 400, and 600 hours of 350nm UV light irradiation. The results were as follows. 1. According to type of pigments, after 200 hours cosmetic red showed significantly larger color change than cadmium yellow and titanium white, and after 400 and 600 hours color change significantly decreased in the order of cosmetic red, cadmium yellow, and titanium white (p<0.05). 2. In the cadmium yellow group, after 200 hours, the non-treatment group showed significantly larger color change, but after 400 and 600 hours, color change significantly decreased in the order of non-treatment, surface application and mixed group (p<0.05). 3. In the titanium white group, there was no significant color change difference between the three groups after 200 and 400 hours, but after 600 hours, the mixed group showed significantly smalt or color change than the non-treatment and surface application groups (p<0.05). 4. In the cosmetic red group, there was significant decrease in color change in the order of non-treatment, surface application and mixed group (p<0.05). From the results above, the effect of UV light absorber differed according to the type of pigment, but mixing UV light absorber with maxillofacial silicone is thought to give superior resistance against UV light irradiation in the long run.

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일본 유료 노인홈의 현황과 그 문제점 분석 - 우리나라 노인 복지법 개정에 즈음하여 - (The condition and the analysis of the problems of the Japanese - The change of the Korean geriatric security law -)

  • 신경주
    • 한국주거학회:학술대회논문집
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    • 한국주거학회 1993년도 학술발표대회논문집
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    • pp.13-20
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    • 1993
  • In Korea, the elderly support has been accomplished by the families in the extended family system with the influence of the transmigration and the confucianism thought. But in Korea the drastic changes of society such as, the growth of the elderly pollution, the urbanization, the decrease of the birth rate, the increase of the working women, the growth of the nuclear families, etc., make the family difficult to take care of the elderly. Therefore, some people insist on the construction of the elderly home as the way to solve the elderly problems and some of corporations including profit-organizations are ready to participate the construction of the elderly home. They force the change of the current social security law because it is impossible to carry out the plans uncer the law. At this point, the conditions of the elderly home in Japan which is geographically close to Korea and has facillicated the elderly home business were examined at the consumer perspectives. The purpose of this study were to consider the possible problems in the elderly home and to prevent from happening another elderly problems in the future.

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Bumetanide의 이뇨작용에 관한 연구 (Studies on Diuretic Action of Bumetanide)

  • 고석태;김일용
    • 약학회지
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    • 제29권3호
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    • pp.130-143
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    • 1985
  • Bumetanide, when given intravenously in dogs, induced a potent diuresis with an increased amounts of sodium and potassium excreted in urine due to inhibition of reabsorbing them in renal tubule. Furthermore, clearances of osmolar substance and para-aminohippuric acid were increased, but clearace of free water diminished without any change of creatinine clearance. Bumetanide, administered directly into a renal artery, elicited diuresis only in the infused(experimental) kidney by the same mode of action as in the intravenous cases in renal function of the dog. Renal effects of intravenous bumetanide after pretreatment with the small dose of indomethacin (5.0mg/kg) revealed reduction only in clearance of paraaminohippuric acid. However the much dose of indomethacin (5.0mg/kg+5.0mg/kg/hr) or arachidonic acid showed a significant inhibition in the change rates of all renal function by bumetanide. Morover, pretreatment of probenecid also made a marked reduction in renal effects induced by bumetanide. From the above results, it is thought that bumetanide causes diuretic action due to dual mechanism inhibiting reabsorption of electrolytes in loop of Henle and increasing blood flow in kindney, that are provoked through the mediation of prostaglandins.

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Epigenetics와 정신장애 (Epigenetics and Psychiatric Disorders)

  • 오대영;양병환;이유상
    • 생물정신의학
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    • 제15권4호
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    • pp.243-253
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    • 2008
  • In the post-genomic era, the mechanisms controlling activation of genes are thought to be more important. Gene-environment interactions are crucial in both development and treatment of psychiatric disorders as they are complex genetic disorders. Epigenetics is defined as a change of gene expression that occurs without a change of DNA sequence and can be heritable by certain mechanisms. Epigenetic changes play essential roles in control of gene activation. DNA methylation, chromatin remodeling and RNAi act as key mechanisms for epigenetic modifications of genes. Here, we review the basic mechanisms of epigenetics and discuss their potential involvement of human diseases, including psychiatric disorders.

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헤어드라이기의 팬 형상에 따른 열변형에 관한 연구 (A Study on Thermal Deformation due to Fan Shape of Hair Dryer)

  • 한문식;조재웅
    • 한국기계가공학회지
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    • 제16권3호
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    • pp.82-87
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    • 2017
  • This study investigates thermal deformation due to fan shape of a hair dryer. In this study, thermal analysis showed that the shape of an electric fan results in lower temperature than that of a sieve frame. Among the shapes of electric fans, the temperature change decreases as the number of wings decreases. As a result of thermal deformation, model 4 (sieve frame shape) showed increased change of deformation compared to models 1, 2, and 3 (with electric fan shapes). Thus, the model 1 dryer with the sieve frame shape is shown to have the least durability among models 1, 2, 3, and 4. It is thought that the analysis results of this study can be applied to durability improvement and safer design of hair dryers.

아나필락시스에 의한 심전도 변화 1례 (A Case of Electrocardiographic Change Associated with Anaphylaxis)

  • 이동훈;장혜영;어은경;정구영
    • 대한임상독성학회지
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    • 제2권1호
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    • pp.12-14
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    • 2004
  • Anaphylaxis is a systemic allergic reaction which can bring fatal results. The common symptoms are erythema, angioedema, urticaria, hypertension and dyspnea. However, in very few cases, ST segment changes in the electrocardiogram can be seen. This is a case of a 51 year old female with normal heart function who showed reversible ST segment depression during anaphylaxis caused by a $H_2$-blocker agent. The cause of ST segment changes during anaphylaxis is thought to be the result of coronary vasospasm mediated by various factors.

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기후변화에 따른 낙동강 유역 농업용수 영향 분석 (Climate Change Impacts on Agricultural Water in Nakdong-river Watershed)

  • 지용근;이진희;김상단
    • 한국농공학회논문집
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    • 제54권3호
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    • pp.149-157
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    • 2012
  • For the systemic management and planning of future agricultural water resources, deriving and analyzing the various results of climate change are necessary to respond the uncertainties of climate change. This study assessed the impact of climate change on the rainfall, temperature, and agricultural water requirement targeting in the Nakdong-river's basin periodically according to socioeconomic driving factors under the scenarios A1B, A2 and B1 of the Special Report on Emission Scenarios (SRES) through the various IPCC GCMs. As a result of future rainfall change (2011~2100), increasing or decreasing tendency of rainfall change for future periods did not show a clear trend for three rainfall observatories, Daegu, Busan and Gumi. The characteristics of the temperature change consistently show a tendency to increase, and in the case of Daegu observatory, high temperature growth was shown. Especially, it was increased by 93.3 % in the period of future3 (2071~2100) for A2 scenario. According to the scenario and periodic analyses on the agricultural water demand, which was thought to be dependent on rainfall and temperature, the agricultural water demand increased at almost every period except during the Period Future1 (2011~2040) with different increase sizes, and the scenario-specific results were shown to be similar. As for areas, the agricultural water demand showed more changes in the sub-basin located by the branch of Nakdong-river than at the mainstream of the River.