• 제목/요약/키워드: CB2

검색결과 582건 처리시간 0.03초

Prediction of Insulation Capability for Ground Fault to Consider Asymmetry in SF6 Circuit Breaker

  • Oh, Yeon-Ho;Song, Ki-Dong;Kim, Hong-Kyu;Lee, Hae June;Hahn, Sung-Chin
    • Journal of Electrical Engineering and Technology
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    • 제10권5호
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    • pp.2046-2051
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    • 2015
  • Currently, most high-voltage gas circuit breakers (CBs) include asymmetrical geometries in the shield, the tank, the hot-gas exhaust, and the connection parts for bushings. For this reason, a 3-dimensional (3-D) analysis of the insulation capability is necessary, rather than a 2-D analysis. However, a 3-D analysis has difficulties due to the computational time and complex modeling. This paper presents a 3-D analysis considering the asymmetry in high-voltage gas CBs and a technique to reduce the calculation time. In the proposed technique, the arc plasma requiring the most computational time is first calculated by a 2-D analysis. Then, the results such as pressure, temperature, and velocity are input as a source for the 3-D analysis. This technique is applied to a 145kV self-blast-type CB and the analysis result exhibits good agreement with the experimental result.

The Role of Air Pollutants in Initiating Liver Disease

  • Kim, Jong Won;Park, Surim;Lim, Chae Woong;Lee, Kyuhong;Kim, Bumseok
    • Toxicological Research
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    • 제30권2호
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    • pp.65-70
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    • 2014
  • Recent episodes of severe air pollution in eastern Asia have been reported in the scientific literature and news media. Therefore, there is growing concern about the systemic effects of air pollution on human health. Along with the other well-known harmful effects of air pollution, recently, several animal models have provided strong evidence that air pollutants can induce liver toxicity and act to accelerate liver inflammation and steatosis. This review briefly describes examples where exposure to air pollutants was involved in liver toxicity, focusing on how particulate matter (PM) or carbon black (CB) may be translocated from lung to liver and what liver diseases are closely associated with these air pollutants.

대변부통(大便不通)의 증상을 가진 소음인(少陰人) 뇌경색 환자에게 온백원(溫白元)을 병용한 치험 2례 (Case Reports of Combined treatment of Onbaek-won on two Soeumin stroke patients with Cb-inf who have Constipation)

  • 이필재;한다님;김성기;임은철;김현진
    • 사상체질의학회지
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    • 제21권3호
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    • pp.168-177
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    • 2009
  • 1. Objectives: The purpose of this case is to report the effects of Onbaek-won which is based on Sasang Constitutional Medicine for constipation in Soeumin. 2. Methods: We treated two Soeumin patients with Constipation. We prescribed Onbaek-won for their physical symptoms. The improvement of their diseases were checked from their stool and other physical symptoms. 3. Results: After the Sasang constitutional medication of Onbaek-won were given, constipation and their physical symptoms were improved. 4. Conclusions: This case study show an efficient result of using Onbaek-won in constipation of Soeumin. Onbaek-won was used instead of Semen Tiglii(巴豆).

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CRDI용 인젝터 드라이버 제작과 성능시험 (The Fabrication and Trial Performance of Injector Driver for CRDI)

  • 김상암;왕우경;김온
    • 동력기계공학회지
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    • 제17권2호
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    • pp.38-45
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    • 2013
  • In this study, for carrying out the spray and combustion experiment using a Common Rail Direct Injection(CRDI) system, the controller was fabricated to drive a high speed camera, a injector and a laser beam sequentially at a low cost. CB280 module of one-chip micro processer was used for the controller. In order to confirm responsibility and utility of the controller, the current drive performance, the spray behavior and the injection rate were tested and analyzed under various experimental conditions. As this research results, we found that the fabricated controller was able to control the devices for the spray experiment precisely with the input value in program and it had the dynamic load responsibility and repetition. Also, we found that the injection rates of our experimental results were higher than those of others at the same injection pressure and the controller connected with the laser system and the data acquisition system had validity for carrying out the spray visualization experiment.

Acid-sensing ion channels (ASICs): therapeutic targets for neurological diseases and their regulation

  • Kweon, Hae-Jin;Suh, Byung-Chang
    • BMB Reports
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    • 제46권6호
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    • pp.295-304
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    • 2013
  • Extracellular acidification occurs not only in pathological conditions such as inflammation and brain ischemia, but also in normal physiological conditions such as synaptic transmission. Acid-sensing ion channels (ASICs) can detect a broad range of physiological pH changes during pathological and synaptic cellular activities. ASICs are voltage-independent, proton-gated cation channels widely expressed throughout the central and peripheral nervous system. Activation of ASICs is involved in pain perception, synaptic plasticity, learning and memory, fear, ischemic neuronal injury, seizure termination, neuronal degeneration, and mechanosensation. Therefore, ASICs emerge as potential therapeutic targets for manipulating pain and neurological diseases. The activity of these channels can be regulated by many factors such as lactate, $Zn^{2+}$, and Phe-Met-Arg-Phe amide (FMRFamide)-like neuropeptides by interacting with the channel's large extracellular loop. ASICs are also modulated by G protein-coupled receptors such as CB1 cannabinoid receptors and 5-$HT_2$. This review focuses on the physiological roles of ASICs and the molecular mechanisms by which these channels are regulated.

Trichoderma asperellum Chi42 Genes Encode Chitinase

  • Loc, Nguyen Hoang;Quang, Hoang Tan;Hung, Nguyen Bao;Huy, Nguyen Duc;Phuong, Truong Thi Bich;Ha, Tran Thi Thu
    • Mycobiology
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    • 제39권3호
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    • pp.182-186
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    • 2011
  • Four Trichoderma strains (CH2, SH16, PQ34, and TN42) were isolated from soil samples collected from Quang Tri and Thua Thien Hue provinces in Vietnam. The strains exhibited high chitinolytic secretion. Strain PQ34 formed the largest zone of chitinase-mediated clearance (> 4 cm in diameter) in agar containing 1% (w/v) colloidal chitin. Analysis of the internal transcribed spacer regions of these strains indicated that they were Trichoderma asperellum. The molecular weights of the chitinases were approximately 42 kDa. Chitinase genes (chi42) of T. asperellum strains TN42, CH2, SH16, and PQ34 were 98~99% homologous to the ech42 gene of T. harzianum CB-Pin-01 (accession No. DQ166036). The deduced amino acid sequences of both T. asperellum strains SH16 and TN42 shared 100% similarity.

비동기적 갱신 선언을 이용한 회피-기반 캐쉬 일관성 유지 기법 (Avoidance-Based Cache Consistency Technique Using an Asynchronous Write Intension Declaration)

  • 장창복;조성훈;강우석;김동혁;이찬섭;박용문;최의인
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2002년도 춘계학술발표논문집 (상)
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    • pp.23-26
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    • 2002
  • 클라이언트/서버 데이타베이스 시스템 환경이 대중화됨에 따라 클라이언트 캐쉬 데이터의 일관성을 유지하기 위한 기법들이 많이 제안되고 있다. 기존의 회피-기반 기법들은 갱신의도(write intuition) 선언을 동기적(synchronous)으로 수행하는 CB(Callback) 기법과 지연(defereed)하는 O2PL(Optimistic 2-Phase Locking) 기법을 기반으로 연구가 이루어졌다. 본 논문에서는 회피-기반(avoidance-based)에서 서버에게 갱신의도 선언을 비동기적으로 수행하는 캐쉬 일관성 유지 기법을 제안한다. 본 논문에서 제안한 기법은 갱신의도 선언을 비동기적으로 수행함으로 서버의 응답을 기다리지 않고 트랜잭션 처리를 수행함으로써 좋은 성능을 보이고, 트랜잭션 철회(abort)율이 낮다는 장점을 갖는다.

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Carbon Black 첨가에 따른 액상 실리콘 고무(LSR)의 기계적 특성 및 경화 거동 분석 (Effects of Carbon Black on Mechanical Properties and Curing Behavior of Liquid Silicone Rubber (LSR))

  • 이범주;김선주;유형민
    • Design & Manufacturing
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    • 제17권2호
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    • pp.27-32
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    • 2023
  • Liquid silicon rubber (LSR) has fine thermal compatibility and is widely used in various fields such as medical care and automobiles because it is easy to implement products with good fluidity. With the recent development of flexible sensors, the focus has been on manufacturing conductive elastomers, such as silicone as elastic materials, and carbon black, CNT, and graphene are mainly used as nanomaterials that impart conductive phases. In this study, mechanical behavior and curing behavior were measured and analyzed to manufacture a CB-LSR complex by adding Carbon Black to LSR and to identify properties. As a result of the compression test, the elastic modulus tended to increase as carbon black was added. When the swelling test and the compression set test were conducted, the swelling rate tended to decrease as the content of carbon black increased, and the compression set tended to increase. In addition, DSC measurements showed that the total amount of reaction heat increased slightly as the carbon black content increased. It is considered that carbon black was involved in the crosslinking of LSR to increase the crosslinking density and have a positive effect on oil resistance reinforcement.

Evaluation of the geogrid-various sustainable geomaterials interaction by direct shear tests

  • Bahadir Ok;Huseyin Colakoglu;Umud Dagli
    • Geomechanics and Engineering
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    • 제34권2호
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    • pp.173-186
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    • 2023
  • In order to prevent environmental pollution, initiatives to increase the sustainability of resources are supported by society. However, the performance of recycled materials does not generally match that of natural materials. This study looks into the use of geogrid to improve various types of recycled aggregates. For this purpose, five different recycled aggregates were created by recycling wastes from the construction industry. Besides, direct shear tests (DS tests) were carried out on these recycled aggregates to determine their shear strengths. Following that, a triaxial geogrid was placed in the recycled aggregates to provide reinforcement, and the DS tests were conducted on the reinforced recycled aggregates. The results of the tests were also compared to those of tests performed on natural aggregates (NA). In conclusion, it was found that the recycled aggregates have lower shear strengths than the NA. Nonetheless, when reinforced with geogrid, the shear strength of the recycled concrete aggregates (RCA) and construction and demolition wastes (CDW) exceeded that of the NA. Furthermore, the geogrid reinforcement increased the shear strength of the recycled crushed bricks (CB), though not to the level of the NA.

덱스트란수크라제를 이용한 전분의 변형 및 특성 조사 (Modification of Starch using Dextransucrase and Characterization of the Modified Starch.)

  • 이진하;김도만;백진숙;박관화;한남수
    • 한국미생물·생명공학회지
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    • 제26권2호
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    • pp.143-150
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    • 1998
  • 덱스트란수크라제는 sucrose를 이용하여 덱스트란의 합성을 촉진하는데 sucrose이외에 다른 탄수화물이 효소 반응기 중에 존재하는 경우에는 sucrose의 glucose기를 이 탄수화물에 전달하는 반응을 촉진하여 새로운 구조의 산물을 생산한다. Leuconostoc mesenteroides B-742CB로 부터 얻은 덱스트란수크라제를 이용하여 입자 전분과 호화 전분에 sucrose의 glucose를 수식함으로써 변형을 시도하였다. 사용한 전분의 종류(Small starch 또는 Potato starch)에 따라 그리고 전분의 상태(입자 혹은 호화된 상태)에 따라 이론적 수율의 46-72%(s.d.<${pm}$5)를 얻었다. 변형 전분을 ${alpha}$-amylase, isoamylase, pullulanase 그리고 endo-dextranase로 처리하여 변형 전의 전분과 가수분해 상태를 비교한 결과 변형전의 산물에 비해 이들 가수분해효소에 대해 저항성을 보였다. 변형에서 얻어진 산물들의 methylation결과 입자 전분을 이용한 변형 반응의 산물의 변형 정도가 더 컸으며, 변형입자를 SEM으로 관찰하면 불규칙한 크기의 작은 조각의 산물을 확인할 수 있었다. 변형 반응으로 sucrose의 glucose가 전분 glucose의 C3, C4, 그리고 C6 위치의 free-OH group에 수식된 새로운 구조의 변형 산물을 생산하였고 이는 iodine에 의한 염색 정도를 크게 감소시켰으며 용해성을 증가시켰다.

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