• 제목/요약/키워드: Recovery factor

검색결과 811건 처리시간 0.028초

초청정 클린룸 난류유동장내에서의 오염입자 비정상 전파거동에 관한 연구 (Study on the Unsteady Contaminated Particle Transportation in the Flow Field for the Super Clean Room)

  • 오명도;임학규;배귀남
    • 대한기계학회논문집
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    • 제14권2호
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    • pp.430-439
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    • 1990
  • Steady state turbulent airflow and unsteady characteristics of generation, transportation, and recovery behavior of contaminate particles in the simplified 2 dimensional Vertical Laminar Flow (VLF) type clean room was numerically simulated using the low Reynolds number k-over bar.epsilon- turbulent model. Characteristics of airflow in VLF type clean room are greatly affected by the recirculation zone around working surface. The recirculation zone must be considered at the time of clean room design because the recirculation zone whose area increases with increment of inlet velocity exerts bad influence upon the performance of clean room in terms of particle contamination. The location of maximum particle concentration changes from the location of particle source to the recirculation zone, while averaged particle concentration is reduced exponentially with time. Recovery time of clean room with spontaneous particle generation source is inversely proportional to inlet velocity. We introduce nondimensionalized recovery time through the dimensional analysis, which can indicates the general performance of clean room with design structure change. It was identified that .tau. is independent of inlet velocity and background concentration. Therefore .tau. can be the simple factor to compare the different structure of clean room in terms of dynamic response to contamination and becomes larger with better structure of clean room.

특발성 안면신경마비 환자의 일반적 특성 및 치료경과와 비수(肥瘦)에 따른 임상적 고찰 (A Clinical Study about General Characteristics, Treatment Progress and Obesity-underweight of Idiopathic Facial Paralysis (Bell's palsy))

  • 정유선;장수영;신현철
    • 대한한방내과학회지
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    • 제34권1호
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    • pp.86-99
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    • 2013
  • Objectives : The purpose of this study was to analyze the general features of patients with idiopathic faical paralysis. Methods : We investigated the various features and HBGS (House-Brackmann Grading System) of 505 patients who were diagnosed with idiopathic facial paralysis. Results and Conclusions : 1. The sex distribution was 264 male cases, and 241 female cases, and the majority of them were in their 40s. 2. Overwork was the most frequent contributing factor to their paralysis. 3. The treatment of most patients was completed within 2 months. 4. Their recovery was faster if their first hospital visit was sooner and their paralysis was partial. On average, the patients recovered within 19.5 to 27.8 days and it took much less time than natural recovery. 5. When looking at the BMI of the selected patients for this study, 62.00% were obese while 14.37% were under-weight. Among the obese patients, there were more with Xu mai (虛脈) than Shi mai (實脈). For the under-weight patients, most had Shuo mai (數脈) while none had Chi mai (遲脈).

ASME Boiler & Pressure Vessel Code에 따른 배열회수보일러 기수분리기의 피로 평가 (Fatigue Evaluation of Steam Separators of Heat Recovery Steam Generators According to the ASME Boiler and Pressure Vessel Code)

  • 이부윤
    • 한국기계가공학회지
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    • 제17권4호
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    • pp.150-159
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    • 2018
  • The present research deals with a finite element analysis and fatigue evaluation of a steam separator of a high-pressure evaporator for the Heat Recovery Steam Generator (HRSG). The fatigue during the expected life of the HRSG was evaluated according to the ASME Boiler and Pressure Vessel Code Section VIII Division 2 (ASME Code). First, based on the eight transient operating conditions prescribed for the HRSG, temperature distribution of the steam separator was analyzed by a transient thermal analysis. Results of the thermal analysis were used as a thermal load for the structural analysis and used to determine the mean cycle temperature. Next, a structural analysis for the transient conditions was carried out with the thermal load, steam pressure, and nozzle load. The maximum stress location was found to be the riser nozzle bore, and hence fatigue was evaluated at that location, as per ASME Code. As a result, the cumulative usage factor was calculated as 0.00072 (much less than 1). In conclusion, the steam separator was found to be safe from fatigue failure during the expected life.

수성이상계를 이용한 재조합 hGM-CSF의 in situ 분리

  • 표세홍;명현종;김동일
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2002년도 생물공학의 동향 (X)
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    • pp.321-324
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    • 2002
  • 본 연구에서는 hGM-CSF를 생산해 배지 내로 분바하도록 유전자 조작된 Nicotiana tabacum 세포를 수성이상계 내에서 배양하여 in situ recovery를 시도하였다. 특히 식물세포 자체의 생상에 큰 영향을 주지 않으면서도 일반 배지에서 회수한 단백질에 비해 많은 양을 생산할 수 있는 수성이상계 시스템을 선정하였다. 6% (w/w) PEG 20,000과 10% (w/w) dextran 2.000,000 을 이용하는 경우 최대 세포 농도가 18.6 g/L 로, 일반배지를 사용하는 경우 (15.7 g/L)에 비해 저해가 없음을 확인하였다. 또한 목적 단백질인 hGM-CSF의 생산에 있어서도 위의 시스템의 경우 dextran-rich phase인 아랫 상으로 분배됨으로 인해 회수가 쉬울 것으로 확인되었으며 그 생산량 또한 일반배지에서의 생산량 (1.5 ng/mL)에 비해 크게 다르지 않음을 확인할 수 있었다. 따라서 hGM-CSF의 회수를 위한 in situ recovery 시스템에 있어서 수성이상계의 이용 가능성을 확인하였다.

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The Performance of Anion Exchange Expanded Bed Adsorption Chromatography on the Recovery of G6PDH from Unclarified Feedstock with High Biomass Concentration

  • Chow, Yen Mei;Tey, Beng Ti;Ibrahim, Mohd Nordin;Ariff, Arbakariya;Ling, Tau Chuan
    • Biotechnology and Bioprocess Engineering:BBE
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    • 제11권5호
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    • pp.466-469
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    • 2006
  • The bed stability of Streamline DEAE (p = 1.2 g/mL) in a 20mm (i.d.) glass expanded bed contactor, and its performance on the recovery of glucose 6-phosphate dehydrogenase (G6PDH) from unclarified yeast homogenate were investigated. A residence time distribution study showed that a stable expanded bed was achieved. The theoretical plate and Bodenstein numbers determined were 25 and 53, respectively. A recovery yield of 87% and purification factor of 4.1 were achieved in the operation using 5% (w/v) biomass concentration feedstock. The performance of the anion exchange EBAC was still considerable good at a biomass concentration as high as 15% (w/v).

인터넷 쇼핑몰 유형별 패션 소비자의 서비스 회복 공정성 지각, 구매 만족도, 긍정적 구전의도 및 재구매의도에 관한 연구 (A Study on the Service Recovery Justice Perception, Purchase Satisfaction, Positive Word-of-Mouth Intention, and Repurchase Intention of Fashion Consumers according to the Types of Internet Shopping Malls)

  • 이은진
    • 한국의류학회지
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    • 제35권7호
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    • pp.787-800
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    • 2011
  • This study investigated service recovery justice perception, purchase satisfaction, positive word-of- mouth (WOM) intention, and repurchase intention of fashion consumers according to the types of internet shopping malls. A survey was conducted from December 20 in 2010 to January 28 in 2011, and 324 respondents who had complaint with internet shopping malls were used in the data analysis. The statistical analysis methods were frequency analysis, factor analysis, reliability analysis, t-test, ANOVA, and multiple regression analysis. The results of this study were as follows. First, in case of integrated internet shopping malls, the procedure justice influenced the purchase satisfaction and the interaction justice influenced the positive WOM intention. In addition, the distribution justice influenced the repurchase intention of fashion consumers. In the case of an open market, the interaction justice influenced the purchase satisfaction and the distribution justice influenced the positive WOM intention. In case of specialized internet shopping malls, the distribution justice influenced the purchase satisfaction and the interaction justice influenced the repurchase intention. Second, there was a difference in the procedure justice, positive WOM intention, and repurchase intention according to gender.

의복의 구속성에 관한 연구(I) -지속적인 구속방법에 따른 피부온 변화에 대하여- (Studies on Garment Restraint(I) -Change of Skin Temperature by Continuous Restraint Method-)

  • 심부자
    • 대한가정학회지
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    • 제29권1호
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    • pp.13-25
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    • 1991
  • We measured change of peripheral skin temperature and mean skin temperature when the upper arm and thigh are pressured in order to know the effect of skin pressure applied by clothing on blood circulation. After release from pressure, we observed also recovery condition. At the same time, we examined relation between pressure and a feeling of thightness. Three physiques of healthy females, namely slender, standard and plump, served as subjects. We used continuous restraint method with skin pressure applied by experimental fabric for 10 min. As a result of this experiment, we obtained following findings. 1. The significant difference was marked at the pressure, measuring time and physique with change of skin temperature under upper arm restraint. The peripheral and mean skin temperature decreased with the lapse of restraint time. A remarkable tendency observed according to the increase of restraint pressure. Recovery condition after release from pressure not yet recovered to original state, for all after a lapse of 10 min. 2. The significant difference was marked at the pressure, measuring time and physique with change of skin temperature under thigh restraint, especially different physique was remarkable among them. The peripheral skin temperature decreased or decreased. Recovery condition after release from pressure was the same upper arm. 3. Main factor affecting the evaluation of a feeling of tightness was restraint pressure. The value of pressure sensation made remarkable declined after a lapse of 10 min restraint time. Individual differences, however, were shown in pressure sensation.

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골격근 손상에 대한 '사향서활정(麝香舒活精)' 치료 효과에 대한 조직형태학적 관찰 (Histological Analysis Effect of 'Sexiang Shuhuo Jing' for after Skeletal Muscle in Rats)

  • 김진항;송제호
    • 동의생리병리학회지
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    • 제20권6호
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    • pp.1543-1547
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    • 2006
  • The aim of this experiment was to observe and analysis clinical effect of the 'Sexiang shuhuo Jing' on histological change for 14days after skeletal muscle injury in rats. The gastrocnemius muscles of rats were damaged by electromechanical and serial cryosections of the damaged muscle were prepared at 1, 5, 10, 14 days after injury. Muscle sample of the both control and 'Sexiang Shuhuo Jing' treated group were prepared for histological analysis by optical microscope and electron microscopy. 'Sexiang Shuhuo Jing' treatment group's skeletal muscle recovery was much more faster than control group. After 5 day's 'Sexiang Shuhuo Jing' treatment group's basically recovery normal structure of muscle fiber. After 14 day's control group's damaged muscle were basically recovery structure of muscle fiber but still has some factor of pathological impression but in Sexiang Shuhuo Jing treatment group's can't be found that.

[ $CO_2$ ] Sequestration on Various Structures of Natural Gas Hydrate Layer for Effective Recovery of $CH_4$ Gas

  • Park, Young-June;Choi, Suk-Jeong;Shin, Kyu-Chul;Seol, Ji-Woong;Lee, Hu-En
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2006년도 춘계학술대회
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    • pp.410-411
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    • 2006
  • On the continental margins and in permafrost regions, natural gas, which has been expected to replace petroleum energy, exists In solid hydrate farm. World hydrate reserves Including natural gas are estimated at about twice as much as the energy contained In total fossil fuel reserves. Because of its vast quantities, the efficient recovery of natural gas from natural gas hydrate becomes the most important factor on evaluating the economic feasibility in the sense of commercialization. It has been noted that carbon dioxide, one of the well-known green house gases, possibly can be stored in the ocean floor as a carbon dioxide hydrate. If the natural gas hydrate could be converted into carbon dioxide hydrate, natural gas hydrate deposits would serve as energy sources as well as carbon dioxide storage sites in the deep ocean sediments. In this study, we first attempted to examine the real swapping phenomenon occurring between guest molecules and various structures of gas hydrate through spectroscopic identification such as NMR spectroscopy.

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DNA Double-Strand Breaks Serve as a Major Factor for the Expression of Arabidopsis Argonaute 2

  • Lee, Sungbeom;Chung, Moon-Soo;Lee, Gun Woong;Chung, Byung Yeoup
    • 방사선산업학회지
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    • 제10권4호
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    • pp.243-248
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    • 2016
  • Argonaute 2 (AtAGO2) is a well characterized effector protein in Arabidopsis for its functionalities associated with DNA double-strand break (DSB)-induced small RNAs (diRNAs) and for its inducible expression upon ${\gamma}$-irradiation. However, its transcriptional regulation depending on the recovery time after the irradiation and on the specific response to DSBs has been poorly understood. We analyzed the 1,313 bp promoter sequence of the AtAGO2 gene ($1.3kb_{pro}$) to characterize the transcriptional regulation of AtAGO2 at various recovery times after ${\gamma}$-irradiation. A stable transformant harboring $1.3kb_{pro}$ fused with GUS gene showed that the AtAGO2 is highly expressed in response to ${\gamma}$-irradiation, after which the expression of the gene is gradually decreased until 5 days of DNA damage recovery. We also confirm that the AtAGO2 expression patterns are similar to that of ${\gamma}$-irradiation after the treatments of radiomimetic genotoxins (bleomycin and zeocin). However, methyl methanesulfonate and mitomycin C, which are associated with the inhibition of DNA replication, do not induce the expression of the AtAGO2, suggesting that the expression of the AtAGO2 is closely related with DNA DSBs rather than DNA replication.