• Title/Summary/Keyword: Systematic reduction study

검색결과 330건 처리시간 0.029초

Fatigue characteristics of $Pb(Zr,Ti)O_3$ capacitors on donor doping

  • Yang, Bee Lyong
    • 열처리공학회지
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    • 제15권3호
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    • pp.113-117
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    • 2002
  • Fatigue characteristics of ferroelectric $Pb(Zr,Ti)O_3$ (PZT) based capacitors through donor doping is reported in this paper. La substitution up to 10% were carried out to study systematically the fatigue behaviors of epitaxial ferroelectric capacitors grown on Si using $(Ti_{0.9}Al_{0.1})N/Pt$ conducting barrier composite. Ferroelectric capacitors substituted with 10% La show sufficient low voltage switched polarization and fatigue free performance. Systematic decrease in the tetragonality of the ferroelectric phase (i.e., c/a ratio) results in the corresponding reduction in coercive voltage, sufficient remnant polarization at 1.5-3V, and good fatigue property.

철도차량 전과정 단계별 온실가스 발생량 비교를 통한 저탄소 운영방안 연구 (Low Carbon operation study through comparing GHG contribution of each stages of railway vehicle)

  • 이철규;김용기
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2010년도 춘계학술대회 논문집
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    • pp.183-186
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    • 2010
  • Advanced Railway countries are developing technologies of production and management for low-carbon and green growth of their railway industry to hold a dominant position under post-Tokyo protocol regime through integrated approach which uses environmental quantitative analysis of train life cycle by using LCA(Life Cycle Assessment). On the contrary, Korea railroad industry attempts to make an environmental improvement only for using regenerative energy and improvement in operating energy consumption through adapting reduction weight of material technology and etc. without systematic environmental analysis approaches such as comparing and analyzing energy consumption as well as GHG emission in each life cycle stages of train. Therefore, In this paper, low-carbon management and comprehensive environmental improvement for sustainable development of Korea railway industry through analyzing the result of life cycle analysis in abroad are suggested.

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VRML 모델을 이용한 쾌속조형에 관한 연구 (A Study on Rapid Prototyping using VRML Model)

  • 김호찬;이주호;반갑수;최홍태;이석희
    • 한국정밀공학회지
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    • 제17권7호
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    • pp.63-73
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    • 2000
  • Internet becomes very common tool for communication and data sharing. Virtual reality(VR) on web browser, and virtual prototyping and virtual manufacturing is widely used in many engineering folds. The reduction of overall development process and error minimization during data conversion becomes very crucial where sharing data via Internet and VR. This paper deals with the advantage and disadvantage of VRML format used in RP(Rapid Prototyping), and a software for RP data preparation is developed. If VRML format as an international standard for VR, is replaced with STL format, the weak points of STL format can be overcome and the technique related to virtual prototyping and virtual manufacturing can be addressed more systematically by sharing the data. The system developed in this work shows a good window to get access to a more realistic observation of an object fur an RP system from a long remote sites in a more systematic way.

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Bioactive Conjugated Linoleic Acid (CLA) in Milk

  • Kee, Jun-Ill;Ganesan, Palanivel;Kwak, Hae-Soo
    • 한국축산식품학회지
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    • 제30권6호
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    • pp.879-885
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    • 2010
  • Conjugated linoleic acid (CLA) isomers are found naturally in foods, such as milk, milk products, beef and others, from biohydrogenation of vegetable oils. They are heterogenous group of isomers of linoleic acid in the family of polyunsaturated fatty acids. Among the isomers of linoleic acid cis9, trans11- CLA (c9, t11-CLA) and trans10, cis12- CLA (t10, c12-CLA) are found to be biologically active isomers. These biologically active isomers either individual or combined found to be health beneficial in various diseases, such as cancer, diabetes, obesity, and atherosclerosis, conclusive participation in physiological processes are necessary. This review focused on the current study of CLA in prevention of disease, such as cancer, diabetes and atherosclerosis, and their effective function in body fat reduction, improvement of bone and muscle mass at a cellular, clinical and systematic level.

국내의 휘발성유기화합물(VOC) 현황 및 관리기술 (Trends and Control Technologies of Volatile Organic Compound)

  • 김조천
    • 한국대기환경학회지
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    • 제22권6호
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    • pp.743-757
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    • 2006
  • Volatile organic compound (VOC) has been well-known to Korea since the end of 1990's however, it has not been well documented until now. In this study, present ambient VOC levels, VOC emission sources, and VOC control technologies were reviewed and discussed. In addition, VOC management strategies to cut down ozone concentrations were suggested based on the present VOC database. For anthropogenic VOC reduction, VOC emitted from painting processes and automobiles should be controlled in the first place in large cities such as Seoul, Daegu, and Incheon. For natural VOC management, low emission trees need to be planted in those cities. It is also very significant to keep updating present and future VOC emission inventories for efficient VOC control strategies. As a conclusion, more systematic VOC control road-map based on BACT (best available control technology) needs to be made up. and more economical and efficient VOC control techniques have to be developed under strong national support in order to lower toxic VOC and photochemical oxidant levels.

A Case Study on Network Status Classification based on Latency Stability

  • Kim, JunSeong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제8권11호
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    • pp.4016-4027
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    • 2014
  • Understanding network latency is important for providing consistent and acceptable levels of services in network-based applications. However, due to the difficulty of estimating applications' network demands and the difficulty of network latency modeling the management of network resources has often been ignored. We expect that, since network latency repeats cycles of congested states, a systematic classification method for network status would be helpful to simplify issues in network resource managements. This paper presents a simple empirical method to classify network status with a real operational network. By observing oscillating behavior of end-to-end latency we determine networks' status in run time. Five typical network statuses are defined based on a long-term stability and a short-term burstiness. By investigating prediction accuracies of several simple numerical models we show the effectiveness of the network status classification. Experimental results show that around 80% reduction in prediction errors depending on network status.

주거용부문의 DSM 절전잠재량 추정 (Estimating DSM Potentials in Residential Sector)

  • 이창호;조인승
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 하계학술대회 논문집 D
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    • pp.982-984
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    • 1997
  • DSM activities have grown and matured over several years in Korea. KEPCO is currently offering some DSM programs in industrial, commercial, and residential customers such as rebate program in purchasing efficient measures. The systematic evaluation process of energy savings and peak reduction will be very important for deciding on the optimal investment of DSM activities in utilities in the future. In general, the estimation process of the potential savings of DSM activities include the determination of baseline electricity consumption, the instantaneous technical potential (ITP), the phased technical potential (PTP), the economic potential (EP), and the achievable potential (AP). The purpose of this article is to provide evaluation process of those DSM potential savings based on bottom-up approach and applicate to residential sector in Korea. In case study, ITP, EP are estimated to be respectively 21.5%, 5.7% of total energy consumption, and 4.1%, 2.5% of peak load in 2010.

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모드 분리 기법을 이용한 스위치 컨버터의 전도잡음 분석 및 대책에 관한 연구 (Study on the analysis and suppression of conducted noise from switching converter by the mode separation technique)

  • 김진성;권준혁;김양모
    • 전자공학회논문지S
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    • 제35S권4호
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    • pp.128-138
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    • 1998
  • This paper describes a principle of the conducted noise separator which can separate the conducted noise to the common mode and differential mode(normal mode), and presents the transfer characteristics of the separator designed and manufactured. We separated the conducted noise generated from switched mode converter to the CM and DM conducted noise, and also analyzed the source and path of conducted noise in the converter by the conducted noise separator. Since we could easily get the characteristics of the CM and DM conducted noise by the separator, we could efficiently determine the contermeasures for the reduction of the conducted noise and establish the foundation of the systematic procedure for the design of low pass filter.

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Characteristics of Negative Peak Wind Pressure acting on Tall Buildings with Step on Wall Surface

  • Yoshida, Akihito;Masuyama, Yuka;Katsumura, Akira
    • 국제초고층학회논문집
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    • 제8권4호
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    • pp.283-290
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    • 2019
  • Corner cut, corner chamfered or a building shape change are adopted in the design of tall buildings to achieve aerodynamic superiority as well as response reduction. Kikuchi et.al pointed out that large negative peak external pressures can appear near the inside corner of set-back low rise buildings. It is therefore necessary to pay attention to facade design around steps in building surfaces. Peak wind pressures for corner cut or corner chamfered configurations are given in the AIJ code. However, they cannot be applied where there are many variations of vertical and horizontal steps. There has been no previous systematic research on peak wind pressures around steps in building surfaces. In this study, detailed phenomenon of peak wind pressures around steps in buildings are investigated focusing on vertical and horizontal distances from the building's corner.

국내 자폐스펙트럼장애 아동에 대한 가족 중심 중재 효과: 체계적 고찰 - 부모 교육 및 부모 코칭 중심으로 - (Effects of Family-Centered Intervention for Children with Autism Spectrum Disorder in South Korea: A Systematic Review - Focusing on Parent Education and Parent Coaching -)

  • 최윤미;유은영
    • 대한감각통합치료학회지
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    • 제21권3호
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    • pp.65-78
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    • 2023
  • 목적 : 본 연구에서는 체계적 문헌 고찰을 통하여 국내 자폐스펙트럼장애 아동의 보호자를 대상으로 실시한 가족 중심 중재의 효과를 알아보고자 하였다. 연구방법 : 문헌검색은 2011년부터 2021년 사이의 문헌을 RISS, KISS, DBpia를 통하여 검색하였다. 검색어는 '자폐스펙트럼' OR '전반적발달장애' OR '고기능 자폐' OR '아스퍼거' AND '부모 교육' OR '가족중심중재' OR '부모코칭' OR '부모훈련' OR '가족참여' 등을 적용하였다. 선정 기준에 따라 최종적으로 11편의 실험연구를 선정하였다. 결과 : 연구 참가자의 일반적 특성, 중재 전략 및 효과, 중재 프로토콜을 확인한 결과, 연구대상은 영유아기 자폐스펙트럼장애 아동이 가장 많았고, 가족 중심 중재에 어머니들이 주로 참여하였다. 가족 중심 중재의 효과는 아동과 부모에게서 모두 나타났으며, 아동에게서는 상호작용 및 의사소통에 대한 효과가 가장 높은 비중을 차지하였고, 부모에게서는 양육 스트레스 감소 및 양육효능감 향상을 보였다. 중재 전략은 감각통합 중재, 반응적 의사소통 및 상호작용 중심 중재가 가장 많았고, 발달 중심 중재, 긍정적 행동 지원 중재(Positive Behavioral Supports; PBS), 중심축 반응 훈련(Pivotal Response Training; PRT)순으로 나타났다. 결론 : 본 연구의 결과를 통해 가족 중심 중재는 자폐스펙트럼장애 아동의 기능뿐만 아니라 부모의 양육 스트레스 및 양육효능감에 효과가 있음이 확인되었으며 임상 활용의 근거를 제시하였다는 점에서 의의가 있다.