• 제목/요약/키워드: High-isolation

검색결과 1,965건 처리시간 0.032초

분기관 진동에 의한 피로파괴 (Vibration Related Branch Line Fatigue Failure)

  • 전형식;박보용
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 1990년도 추계학술대회논문집; 한양대학교, 서울; 24 Nov. 1990
    • /
    • pp.113-124
    • /
    • 1990
  • Tap lines are small branch piping generally less than two inches in diameter. They typically branch off of header piping having a much larger diameter. An example of a common tap line is a 3/4 inch size high point vent or low point drain. Most tap lines have at least one valve near the header tap connection to provide isolation. Two valves are often required for double isolation. A light water reactor(LWR) nuclear power plant will have several hundred tap lines. These lines come in many sizes and shapes and serve numerous functions. A single process piping valve may have three different tap lines associated with it (figure 1). Table 1 delineates the different categories of tap lines. Vibration failures of tap lines are a common occurrence in all industrial plants including nuclear and fossil power plants. These types of failures constitute a significant percentage of all piping related failures. An unscheduled plant shutdown or outage resulting from the failure of a tap line decreases plant reliability and may have a detrimental effect on plant safety. Most tap line vibration failures can be avoided through the use of appropriate routing and support techniques. Standardized designs can be developed for use in a myriad of applications. These designs will not only minimize failures but will also reduce the necessary analysis and installation efforts.

  • PDF

Waste Isolation Pilot Plant Performance Assessment: Radionuclide Release Sensitivity to Diminished Brine and Gas Flows to/from Transuranic Waste Disposal Areas

  • Day, Brad A.;Camphouse, R.C.;Zeitler, Todd R.
    • Nuclear Engineering and Technology
    • /
    • 제49권2호
    • /
    • pp.450-457
    • /
    • 2017
  • Waste Isolation Pilot Plant repository releases are evaluated through the application of modified parameters to simulate accelerated creep closure, include capillary pressure effects on relative permeability, and increase brine and gas saturation in the operations and experimental (OPS/EXP) areas. The modifications to the repository model result in increased pressures and decreased brine saturations in waste areas and increased pressures and brine saturations in the OPS/EXP areas. Brine flows up the borehole during a hypothetical drilling intrusion are nearly identical and brine flows up the shaft are decreased. The modified parameters essentially halt the flow of gas from the southern waste areas to the northern nonwaste areas, except as transported through the marker beds and anhydrite layers. The combination of slightly increased waste region pressures and very slightly decreased brine saturations result in a modest increase in spallings and no significant effect on direct brine releases, with total releases from the Culebra and cutting and caving releases unaffected. Overall, the effects on total high-probability mean releases from the repository are insignificant, with total low-probability mean releases minimally increased. It is concluded that the modified OPS/EXP area parameters have an insignificant effect on the prediction of total releases.

Selection and Isolation of a Mutant Yeast Strain Tolerant to Multiple Targeted Heavy Metals

  • Lee, Sangman
    • 한국환경농학회지
    • /
    • 제33권2호
    • /
    • pp.129-133
    • /
    • 2014
  • BACKGROUND: This study was performed for selecting yeast mutants with a high tolerance for targeted metals, and determining whether yeasts strains tolerant to multiple heavy metals could be induced by sequential adaptations. METHODS AND RESULTS: A mutant yeast strain tolerant to the heavy metals cadmium (Cd), copper (Cu), nickel (Ni), and zinc (Zn) was selected by sequential elevated exposures to each metal with intermittent mutant isolation steps. A Cd-tolerant mutant was isolated by growing yeast cells in media containing $CdCl_2$ concentrations that were gradually increased to 1 mM. Then the Cd-tolerant mutant was gradually exposed to increasing levels of $CuCl_2$ in growth media until a concentration of 7 mM was reached, thus generating a strain tolerant to both Cd and Cu. In the subsequent steps, this mutant was exposed to $NiCl_2$ (up to 8 mM), and a resultant isolate was further exposed to $ZnCl_2$ (up to 60 mM), allowing the derivation of a yeast mutant that was simultaneously tolerant to Cd, Cu, Ni, and Zn. CONCLUSION: This method of inducing tolerance to multiple targeted heavy metals in yeast will be useful in the bioremediation of heavy metals.

차량용 텔레매틱스 안테나 (Telematics Antenna for Vehicles)

  • 김해연;이병제;양성현
    • 한국컴퓨터산업학회논문지
    • /
    • 제5권2호
    • /
    • pp.331-336
    • /
    • 2004
  • 본 논문은 GPS/GSM 이중대역으로 차량 내부 장착용 텔레매틱스 안테나를 제안하였다. 고유 전율을 가지는 유전체를 사용하지 않으며 두 안테나를 같은 평면에 1mm의 두께를 가지는 fr4기판 위에 설계를 하였다. 이러한 방법으로 제작비용의 절감과 제작공정의 간소화를 추구하였다 GSM 대역은 평면 역 F형 안테나(PIFA)로 구현하였고 GPS 대역의 안테나를 마이크로스 트립 안테나(MSA)로 설계한 PIFA-MSA를 제안하였다. PIFA-MSA는 포트간 격리도 특성을 고려하여 상용 안테나보다 낮게 구현하면서 두 안테나간 편파를 수직으로 배열하여 격리도 특성을 극대화했으며 설계규격 또한 만족 시켰다.

  • PDF

Spontaneous Electrical Activity in Cerebellar Purkinje Neurons of Postnatal Rats

  • Nam, Sang-Chae
    • The Korean Journal of Physiology and Pharmacology
    • /
    • 제1권4호
    • /
    • pp.355-366
    • /
    • 1997
  • Although cerebellar Purkinje cells display spontaneous electrical activity in vivo and in slice experiments, the mechanism of the spontaneous activity generation has not been clearly understood. The aim of this study was to investigate whether cerebellar Purkinje cells of postnatal rats generate spontaneous electrical activity without synaptic inputs. Dissociated cerebellar Purkinje cells were used for reducing synaptic inputs in the present study. Cerebellar Purkinje cells with dendrites were dissociated from postnatal rats using enzymatic treatment followed by mechanical trituration. Spontaneous electrical activities were recorded from dissociated cells without any stimulus using whole-cell patch clamp configuration. Two types, spontaneously firing or quiescent, of dissociated Purkinje cells were observed in postnatal rats. Both types of cells were identified as Purkinje cells using immunocytochemical staining technique with anti-calbindin after recording. Spontaneously active cells displayed two patterns of firing, repetitive and burst firings. Two thirds of dissociated Purkinje cells displayed repetitive firing and the rest of them did burst firing under same recording condition. Repetitive firing activities were maintained even after further isolation using either physical or pharmacological techniques. Neither high magnessium solution nor excitatory synaptic blockers, AP-5 and DNQX, block the spontaneous activity. These results demonstrate that spontaneous electrical activity of isolated cerebellar Purkinje cells in postnatal rats is generated by intrinsic membrane properties rather than synaptic inputs.

  • PDF

Cope씨 침을 이용한 늑막 생검에 관한 임상적 고찰 (clinical evaluation of pleural biopsy by cope needle)

  • 황윤호
    • Journal of Chest Surgery
    • /
    • 제19권3호
    • /
    • pp.374-380
    • /
    • 1986
  • From June 1983 to September 1984, the pleural biopsies with Cope needle were performed at department of thoracic and cardiovascular surgery, Pusan Paik Hospital, Inje college, on 78 patients for exudative pleural effusion caused by various conditions. These results were analyzed clinically and summarized as follows: 2. The accuracy of pleural biopsy was 69.2% [54 of 78 patients]. The accuracy represented by ratio for the number of biopsy was 63.5% [54 of 85 biopsies]. 3. Among 61 patients of tuberculosis or malignancy, 37 [60.7%] were confirmed by pleural biopsy. 4. Tuberculosis was diagnosed in 48 patients, in 26[54.2%] out of these by pleural biopsy alone, in 3[6.2%] by pleural biopsy and isolation of AFB, in 2[4.2%] by pleural biopsy and operation, in 4[8.3%] by isolation of AFB, in 2[4.2%] by operation, and in 11[22.9%] clinically. 5. Among 13 patients of malignancy, 4[30.8%] were diagnosed by cytology alone, 4[30.8%] by pleural biopsy and cytology alone, 4[30.8%] by pleural biopsy and cytology, 1[7.7%] by pleural biopsy alone, 1[7.7%] by pleural biopsy and operation, and remained 3 by operation, lymph node biopsy, or bronchoscopy respectively. 6. False positive of clinical diagnosis was 12.5% for tuberculosis and 28.6% for malignancy. In pathological diagnosis there was no false positive. So specificity of pleural biopsy was very high. But false negative of pleural biopsy was 29.2% for tuberculosis and 46.2% for malignancy. 7. 4 cases[5.1%] of minimal pneumothorax were in the early series.

  • PDF

Isolation, Identification, and Characterization of a Keratin-degrading Bacterium Chryseobacterium sp. P1-3

  • Hong, Sung-Jun;Park, Gun-Seok;Jung, Byung Kwon;Khan, Abdur Rahim;Park, Yeong-Jun;Lee, Chang-Hyun;Shin, Jae-Ho
    • Journal of Applied Biological Chemistry
    • /
    • 제58권3호
    • /
    • pp.247-251
    • /
    • 2015
  • In this study, a keratin-degrading bacterium was isolated from soil contaminated with feather waste. The isolated strain was identified as Chryseobacterium sp. P1-3 on the basis of the 16S rRNA gene sequence alignment. Chryseobacterium sp. P1-3 is currently used in various biotechnological applications (e.g., in the hydrolysis of poultry feathers). It hydrolyzed the feather meal within 2 days and possesses a high level of keratinase activity (98 U/mL). The keratinase, partially purified from this strain, prefers casein as a substrate and shows optimal activity at a temperature of $30^{\circ}C$ and at a pH of 8.0.

Remotely Operated Decontamination Systems for Use in DFDF

  • Kim, Kiho;Park, Jangjin;Myungseung Yang
    • 한국방사성폐기물학회:학술대회논문집
    • /
    • 한국방사성폐기물학회 2003년도 가을 학술논문집
    • /
    • pp.438-446
    • /
    • 2003
  • This paper presents the development of the remotely operated decontamination systems for use in a highly radioactive zone of the DUPIC Fuel Development facility of the Irradiated Material Examination Facility at the Korea Atomic Energy Research Institute. The remotely operated decontamination systems were designed to completely eliminate human interaction with hazardous radioactive contaminants. These decontamination systems are mainly classified into three systems depending on the task environment - a fabrication equipment decontamination system, a hot-cell floor decontamination system, and an isolation room floor decontamination system. A decontamination system for contaminated fabrication equipment utilizes dry ice pellet blasting method to decontaminate contaminated surface of the equipment. The decontamination systems for the hot-cell floor and isolation room floor employ a vacuum cleaning method to decontaminate the contaminated floor and collect loose dry spent nuclear fuel debris and other radioactive waste placed on the floor. The human operator from the out-of-cell performs a series of decontamination tasks remotely by manipulating decontamination systems located in-cell via a handcontroller with the aid of vision feedback information. The environmental, functional and mechanical design considerations, control system and capabilities of the remotely operated decontamination systems at a high radioactive environment are also described.

  • PDF

개구결합 및 3차원 천이 마이크로스트립 선로로 급전되는 이중편파 사각형 마이크로스트립 안테나 (Aperture Coupled and 3-D Transition Microstrip Line Fed Dual Polarization Rectangular Microstrip Antenna)

  • 조성문;박동국
    • 한국전자파학회논문지
    • /
    • 제13권10호
    • /
    • pp.1034-1039
    • /
    • 2002
  • 본 논문에서는 개구결합 급전(포트 1)과 3차원 마이크로스트립 급전(포트 2)을 이용하여 단자간의 분리도가 우수한 이중편파 사각형 마이크로스트립 패치 안테나를 설계하였다. 설계는 각각의 급전방식에서 상용프로그램인 IE3D를 이용한 모의실험을 통하여 파라미터값들의 최적값을 찾고, 그 각각의 최적값을 통합하여 이중편파 마이크로스트립 안테나를 설계하고 제작하였다. 2 GHz 대역에서 실험한 결과 반사손실 10 dB 주파수 대역폭이 17 %이며, 30 dB 이상의 분리도를 확인하였다.

Efficient Isolation of Intact RNA from the Soft Coral Scleronephthya gracillimum $(K\ddot{u}kenthal)$ for Gene Expression Analyses

  • Woo, Seo-Nock;Yum, Seung-Shic;Yoon, Moon-Geun;Kim, Sa-Heung;Lee, Jong-Rak;Kim, Jeong-Ha;Lee, Taek-Kyun
    • Animal cells and systems
    • /
    • 제9권4호
    • /
    • pp.205-209
    • /
    • 2005
  • A rapid, simple and efficient method to extract RNA from the adult polyps of a soft coral, marine cnidarian, Scleronephthya gracillimum $(K\ddot{u}kenthal)$; was developed in this study. The highest yield and purity of RNA was obtained with the lysis solution containing 35 mM EDTA, 0.7 M LiCl, 7.0% SDS, and 200 mM Tris-Cl (pH 9.0). Approximately $40{\mu}g$ of total RNA was extracted from 200 mg of liquid nitrogen-pulverized polyp tissue. The ratio of absorbance at 260 nm and 280 nm ranged from 1.8 to 2.0. The results of the reverse transcription polymerase chain reaction (RTPCR) with ${\beta}-actin$ gene specific primers and Northern blot analysis using the same gene probe revealed that the RNA extracted by our method had high quality, and was sufficient for subsequent molecular biological analyses. This method was effective for RNA extraction from other soft coral species which belong to the genus Dendronephthya.