• 제목/요약/키워드: Isolation rate

검색결과 629건 처리시간 0.027초

Evaluation the Impact of Installing a Isolation Valve on Condensate System of Nuclear Power Plan (원자력발전소 복수기 수실 차단밸브 설치 영향 평가)

  • Lee, Sun-Ki
    • Journal of Industrial Convergence
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    • 제18권4호
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    • pp.15-21
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    • 2020
  • Because there are no isolation valves in condensate system of nuclear power plants, circulating water pump was shutdown for the condenser repair. When circulating water pump was shutdown, power plant output decreased about 45%. These output decreasing can minimize by establishing isolation valves. In this paper, evaluated effect to flow conditions change of condensate system, structural integrity of system, condenser pressure of in case of establish isolation valves to condensate system. Results of the evaluation, the flow rate due to the installation of the isolation valve decreased 0.3% when the valve was fully opened and 4.5% when fully closed. In addition, it was found that the vacuum degree of the condenser decreased with decreasing flow rate, but the integrity of the system was maintained.

Recovery and Survival of Listeria monocytogenes in Surface and Sea Water (지표수 및 해수로부터 Listeria monocytogenes의 분리 및 생존성)

  • Yang, Ju;Kim, Toh-Gyong;Kang, Ho-Jo
    • Korean Journal of Veterinary Research
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    • 제42권3호
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    • pp.327-333
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    • 2002
  • The study was carried out to examine the distribution and survival rate of Listeria monocytogenes (L monocytogenes) from various source of waters using improved isolation method. In comparision of enrichment media for isolation of L monocytogenes from water, the isolation rate and 50% detection limit of the pathogen were higher in UVM modified Listeria enrichment broth (UVM) than Listeria enrichment broth (LEB). On the other hand, when compared the selective media for isolation of the pathogen from water, the isolation rate was highest in culture at Oxford agar followed by Fraser agar, and LEB agar. In order to improve enrichment method, 100 ml of water samples with 0.1 CFU/ml of L monocytogenes was inoculated into 10 ml of UVM concentrated at 10-fold, and incubated for 24 h at $36^{\circ}C$. Isolated frequency of the pathogens in improved enrichment method completely corresponded with common (filter) method. Of a total mumber of 147 water samples from river, lake and sea, the pathogen was isolated from 1 of 39 (2.6%) river water samples and 1 of 75 (1.3%) sea water samples, but no pathogen was isolated from 33 lake water samples. Serotypes of 2 isolates were identified as type 1. L monocytogenes decreased in number from 7.2-7.4 to 4.2-4.7 log CFU/ml for 1 week poststorage (5 and $20^{\circ}C$), but the pathogens were able to be detected in river and sea water until 8 weeks after storage. However, in tap water, L monocytogenes were decreased to undetectable level after 2 weeks of storage.

Isolation and characterization of Staphylococcus hyicus subsp hyicus from chickens (닭으로부터 Staphylococcus hyicus subsp hyicus의 분리(分離) 및 그 특성(特性))

  • Choi, Il-young;Park, Cheong-kyu
    • Korean Journal of Veterinary Research
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    • 제35권3호
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    • pp.497-504
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    • 1995
  • Isolation of Staphylococcus hyicus subsp. hyicus from the skin of healthy chickens was performed and biochemical characteristics of the isolates were examined. Staphylococcus hyicus subsp hyicus was isolated from 129(14.8%) of 874 healthy chickens. The rate of isolation of this organism from chickens was found to vary depending upon the poultry farms at the isolation rate of 0% to 38.7% and this organism was isolated more frequently from adult chickens of over 1 year old than young chickens. All of the isolates were negative for haemolysis on rabbit, sheep, pig and chicken blood agars, protein A and ${\beta}$-glucuronidase, but positive for coagulase using pig plasma, heat-stable DNase, phosphatase and Tween 80 hydrolysis. Hyaluronidase was positive in 97.7% of isolates, but their reaction was weaker than that of swine strains of Staphylococcus hyicus subsp hyicus. The isolates were biotyped on the basis of the reactions for protease, urease, nitrate, galactose, trehalose and lactose, and 11 biotypes were found among the 129 isolates of Staphylococcus hyicus subsp hyicus.

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A Study on the Salmonella spp. isolation method in the sewage specimens (하수중의 Salmonella spp. 분리방법에 관한 비교연구)

  • 김성수;염종화
    • Journal of environmental and Sanitary engineering
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    • 제10권3호
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    • pp.35-44
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    • 1995
  • This study was carried out in order to compare the methods for Salmonella spp. isolation from sewage and to settle the most appropriate conditions for that isolation. The direct enrichment method was more effective than the pre- enrichment method for Salmonella spp. isolation. The rate of detection was much higher when the specimens were enriched at $41.5^{\circ}C$ than when at $35^{\circ}C$. Usage of XLBG agar medium showed better results for Salmonella isolation than that of SS medium. It can be suggested that the most effective combination for Salmonella spp. isolation was the direct centrifugation(3,000 rpm 100m1)- direct enrichment($41.5^{\circ}$C)-usage of XLBG medium.

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Effects on Nurses' Hand Washing Behavior and Reduction of Respiratory Isolation Rate of MRSA of the Hand Washing Education (손씻기 교육이 간호사의 손씻기 행위와 중환자의 호흡기로의 MRSA 분리율 감소에 미치는 영향)

  • Kim, Nam-Cho;Choi, Kyung-Ok
    • Korean Journal of Adult Nursing
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    • 제14권1호
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    • pp.26-33
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    • 2002
  • Purpose: This is a clinical experimental study aimed to provide basic data to ensure quality care. The purpose of this study is to increase nurses hand washing behavior and decrease respiratory isolation rate of MRSA. Method: This study was conducted in Kangnam St. Marys hospital. The subjects included 5 nurses working at the NS ICU and 165 specimen for nasal swabs and 46 specimen for sputum cultures from 106 patients admitted to the NS ICU. The data were collected from June to September 2000. Results: 1.The percentage of the nurses hand washing was 15.6percent but was improved to 46.5 percent after the educational intervention. In particular, hand washing behavior was increased in situations such as after suctioning, before parenteral nutrition, and after providing hygiene care. 2. Results of nasal swab showed that MRSA isolation rate was reduced from 42.8 percent before the education to 18.6percent after the education. The sputum culture results also showed that the MRSA rate was reduced from 40.7percent before the education to 34.6percent after the education. Conclusion: The findings showed the nurses' strict hand washing behavior and use of disposable gloves and paper towers as well as use of hand sterilization spray by visitors or families can decrease the MRSA isolation rate in the NS ICU patients. Since the NS ICU patients may have respiratory complications due to long-term hospitalization, the nurses regular hand washing is important enough to be emphasized. Future research should be focused on the impact of nurses' hand washing behavior on the incidence of pneumonia, an iatrogenic infection.

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A Study on Characterization and Modeling of Shallow Trench Isolation in Oxide Chemical Mechanical Polishing

  • Kim, Sang-Yong;Chung, Hun-Sang
    • Transactions on Electrical and Electronic Materials
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    • 제2권3호
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    • pp.24-27
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    • 2001
  • The end point of oxide chemical mechanical polishing (CMP) have determined by polishing time calculated from removal rate and target thickness of oxide. This study is about control of oxide removal amounts on the shallow trench isolation (STI) patterned wafers using removal rate and thickness of blanket (non-patterned) wafers. At first, it was investigated the removal properties of PETEOS blanket wafers, and then it was compared with the removal properties and the planarization (step height) as a function of polishing time of the specific STI patterned wafers. We found that there is a relationship between the oxide removal amounts of blanket and patterned wafers. We analyzed this relationship, and the post CMP thickness of patterned wafers could be controlled by removal rate and removal target thickness of blanket wafers. As the result of correlation analysis, we confirmed that there was the strong correlation between patterned and blanket wafer (correlation factor: 0.7109). So, we could confirm the repeatability as applying for STI CMP process from the obtained linear formula. As the result of repeatability test, the differences of calculated polishing time and actual polishing time was about 3.48 seconds. If this time is converted into the thickness, then it is from 104 $\AA$ to 167 $\AA$. It is possible to be ignored because process margin is about 1800 $\AA$.

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Investigations on a vertical isolation system with quasi-zero stiffness property

  • Zhou, Ying;Chen, Peng
    • Smart Structures and Systems
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    • 제25권5호
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    • pp.543-557
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    • 2020
  • This paper presents a series of experimental and numerical investigations on a vertical isolation system with quasi-zero stiffness (QZS) property. The isolation system comprises a linear helical spring and disk spring. The disk spring is designed to provide variable stiffness to the system. Orthogonal static tests with different design parameters are conducted to verify the mathematical and mechanical models of the isolation system. The deviations between theoretical and test results influenced by the design parameters are summarized. Then, the dynamic tests for the systems with different under-load degrees are performed, including the fast sweeping tests, harmonic excitation tests, and half-sine impact tests. The displacement transmissibility, vibration reduction rate, and free vibration response are calculated. Based on the test results, the variation of the transmission rule is evaluated and the damping magnitudes and types are identified. In addition, the relevant numerical time history responses are calculated considering the nonlinear behavior of the system. The results indicate that the QZS isolation system has a satisfactory isolation effect, while a higher damping level can potentially promote the isolation performance in the low-frequency range. It is also proved that the numerical calculation method accurately predicts the transmission character of the isolation system.

Improving the Infection and Isolation Alarm Program: a Case Study (감염 및 격리 알람 프로그램 개선: 사례 연구)

  • Min-Ju Nam;Young-Sook Moon;Hee-Ok Kim;Minsu Ock
    • Quality Improvement in Health Care
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    • 제28권2호
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    • pp.39-49
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    • 2022
  • Purpose:The infection and isolation program used at a university hospital in A city was assessed and improved to provide medical staff with easy-to-understand information on isolation precautions and infectious diseases. Methods: Based on the results of the root cause analysis, the infection and isolation alarm computer program was improved. Subsequently, a survey was conducted with infection control leaders and unit managers (n=98) within the department to evaluate the degree of improvement. Results: The isolation registration and release procedures were simplified and unified to prevent confusion among the relevant departments. Additionally, the screen composition was improved so that various information related to infection can be easily accessed. After improvement in the program, the rate of isolation registration (53.0% to 100.0%, p<.001) and user satisfaction (67.6% to 92.2%) improved. Conclusion: This study will help improve the program so that other medical institutions can comply with the isolation precautions in accordance with the type of infections.

Seismic performance of hybrid isolation plate-shell integrated concrete LSS

  • Lei Qi;Xuansheng Cheng;Shanglong Zhang;Yuyue Bu;Bingbing Luo
    • Earthquakes and Structures
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    • 제27권1호
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    • pp.57-67
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    • 2024
  • To assess the seismic performance of Plate-Shell Integrated Concrete Liquid-Storage Structure (PSICLSS), a scaled test model was constructed. This model incorporated a hybrid isolation system, which combined shape memory alloy (SMA), lead-cored rubber isolation bearing (LRB) and sliding isolation bearing (SB). By conducting shaking table test, the dynamic responses of both non-isolated and hybrid-isolated PSICLSS were analyzed. The results show that the hybrid isolation system can effectively reduce the acceleration and displacement responses of the structure. However, it also results in an increase in local hydrodynamic pressure and liquid sloshing height. Under extreme earthquake action, the displacement of isolation layer is small. When vertical ground motion is taken into account, the shock absorption rate of horizontal acceleration decreases. The peak hydrodynamic pressure increases significantly, and the peak hydrodynamic pressure position also changes. The maximum displacement of isolation layer increases, the residual displacement decreases.

Antibiotic Susceptibility and Distribution of Vibrio parahaemolyticus Isolated from the Seafood (어패류에서 분리한 장염비브리오균의 분포 및 항균제 감수성)

  • Lee, Hyang;Oh, Yung-Hee;Choi, Sung-Min;Park, Seog-Gee
    • Journal of Environmental Health Sciences
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    • 제33권1호
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    • pp.16-20
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    • 2007
  • Vibrio parahaemolyticus was investigated for analysis of distribution and antibiotic susceptibility at the markets, Seoul in 2004. The average isolation rate was 26.8%(306/1,143) and the highest rate with 64.9% was obtained in August. The isolation rates from December to April was 0.0%. It is more effective to inoculate into the enrichment medium, alkaline pepton water by swabbing a sample with a cotton ball rather than pouring mixed sample. The isolation rates were from 24.4% to 37.1% in domestic samples and from 9.8% to 26.8% in imported ones. All of the isolates were resistent to ampicillin and ticarcillin and most of them were sensitive to chloramphenicol, tetracycline, nalidixic acid, amoxicillin, ceftriaxone, streptomycin, kanamycin, trimethoprim/sulfamethoxazol, ampicillin/sulbactam, ciprofloxacin.