• Title/Summary/Keyword: Hot-Cold

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Measurements of Five-Hole Pressure Probe on Swirling Flow Fields of Gun-Type Gas Burner for Furnace (온풍난방기용 Gun식 가스버너의 스월유동장에 대한 5공압력프로브의 측정)

  • Kim, Jang Kweon;Oh, Seok Hyung
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.38 no.12
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    • pp.991-997
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    • 2014
  • This study investigated the swirling flow fields of a gun-type gas burner (GTGB) without a combustion chamber under cold flow conditions. Three velocity components and the static pressure were measured with a straight-type five-hole pressure probe (GHPP) using a non-nulling calibration method and compared with the results of an X-type hot-wire probe (X-probe) and computational fluid dynamics (CFD). The GHPP measured the velocity and static pressure for the swirling flow of the central region of the GTGB better than the X-probe but produced slightly worse results than the CFD.

[ $^{99m}Tc-RBC$ ] Hepatic Scintiscan in focal Hepatic Lesions ($^{99m}Tc-RBC$ 간신티스캔을 이용한 간내 공간점유병소의 감별진단)

  • Lee, Do-Yun;Yoo, Hyung-Sik;Lee, Jong-Tae;Kim, Ki-Whang;Park, Chang-Yun;Park, Chan-H.
    • The Korean Journal of Nuclear Medicine
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    • v.21 no.2
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    • pp.191-197
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    • 1987
  • 39 patients with focal hepatic lesions were evaluated by $^{99m}Tc-RBC$ liver scan. The diagnosis of focal hepatic lesions were made by percutaneous needle biopsy, angiography, surgery, or clinical courses. Thses diagnoses included 24 cases of hemangioma, 7 hepatomas, 6 metastatic disease, 1 abscess, and 1 cyst. 19 hemangiomas showed focal hot activity on delayed static planar images. 3 small deep seated hemangiomas were diagnosed by SPECT that would have been missed by planar images alone. 2 large hemangiomas had no radioisotope uptake within the lesions on delayed images and at surgery cavernous hemangioma with thrombosis, calcification, and fibrosis were found. For hepatic hemangiomas in our series, the sensitivity was 91.7% and the specificity was 100%. The remaining 15 patients including hepatomas, metastatic lesions, cyst and abscess showed cold defect on delayed blood pool images. It is concluded that $^{99m}Tc-RBC$ liver scan should be the choice of primary diagnostic procecure for clinically suspected hepatic hemangioma since it's inexpensive, non-invasive, and readly available.

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A study on the Bending Fatigue Strength of Die Steels coated with VC(Vanadium Carbide)by Immersing in Molten Borax Bath (용융염 침적법에 의한 VC coating 금형강의 굽힘 피로강도에 관한 연구)

  • Lee, B.K.;Nam, T.W.
    • Journal of the Korean Society for Heat Treatment
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    • v.6 no.3
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    • pp.166-177
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    • 1993
  • Bending fatigue strength tests were made for VC coated die steels which were coated by immersing in a molten borax bath and for hardened die steels which were quenched and tempered, in order to clarify the effect of VC coating at $1000^{\circ}C$ and $1025^{\circ}C$. The material used in this investigation was a representative cold and hot die steels STD11, STD61. The results obtained are as follows. 1) The endurance limit of VC coated die steels was a little lower than that of hardened die steels. It is considered to be mainly due to the decfl.lase of hardness in the substrates. Accordingly, the endurance limit reo covered almost to the level of hardened die steels by an additional diffusion treatment. 2) The initiation point of fatigue fracture of VC coated die steels in reversed bening was on the substrate just under the VC layer. Hence, the endurance limit is corrected to the hardness of this part. 3) But, there is a considerable scatter in this relationship and the endurance limit of VC coated die steels was a little lower than that of hardened die steels with equal hardness. These results suggest that the fatigue strength of VC coated die steels is determined not only by the hardness but also by other factors. For example. the residual stress in the substrate just under VC coating layer is one of the factors besides hardness which is mainly related to the retained austenite(${\gamma}_R$).

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Screening of Anticoagulant Activities in Extracts from Edible Herbs (허브 추출물의 항응고 활성 검색)

  • 신동훈;이종임;이현순;전우진;유광원;홍범식;조홍연;양한철
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.29 no.2
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    • pp.335-341
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    • 2000
  • In order to search for blood anticoagulant substance from herbal extracts, we extracted with cold water (Fr. I), methanol (Fr. II) and hot water (Fr. III) from 93 commercially available herbs. The anticoagulant activity of herbal extracts was examined through the intrinsic pathway by activated partial thromboplastin time (APTT), the extriansic pathway by prothrombin time (PT) and the common pathway by thrombin time (TT). Onion, garlic, clove, fenugreek, mugwort, thyme and sage had on anticoagulant activity with intrinsic pathway and mint, italian seasoning, rosemary, turmeric, tarragon and wasabie had on anticoagulant activity with common pathway. Nobody had on anticogulant activity with extrinsic pathway. Among commerical herbs tested, clove cultivated in holland was selected because it showed the most potent anticoagulant activity among the samples investigated.

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Comparison of Sleep Pattern, Factors of Sleep Disturbance and Sleep Enhancement Behaviors between Sleep Disturbance and Non-Sleep Disturbance Aged Patients (수면장애 노인 환자와 일반 노인 환자의 수면양상, 수면장애요인 및 수면증진행위)

  • Han, Suk-Jung;Lee, Eun-Young;Kim, Kyung-Mi;Park, Sun-Nam
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.14 no.1
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    • pp.62-71
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    • 2007
  • Purpose: This study was done to compare sleep patterns, factors of sleep disturbance and sleep enhancement behaviors between sleep disturbance and non-sleep disturbance elderly patients. Method: The participants were 117 patients over 65 years old who were hospitalized at 5 general hospitals in Seoul. There were 83 patients in the good sleeper group and 34 in the poor sleeper group. The survey questionnaires included questions on general characteristics, sleep patterns, sleep disturbing factors, and sleep enhancement behaviors of the patients. Results: For sleep patterns and environmental factors of sleep disturbance, the poor sleepers was significantly higher than that of the good sleepers. Significant differences between good sleepers and poor sleepers were also found on the following variables: Environmental factors of sleep disturbance -'Sound of other patient's or care-giver's', 'Discomfort of bed, linen, pillow and patient's gown', 'Light in the room', 'Emergency situations', 'Temperature of patients rooms too hot or too cold'. The significant physical factor of sleep disturbance was 'Hard to breath even without moving' and for sleep enhancement behaviors: 'Use of ear plugs or eye covers' Conclusion: Consequently it is necessary to develop positive and differentiated programs for sleep enhancement for the inactive and poor sleeper among the elderly patients.

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Analysis of Flower Teas for their Oriental Medicinal Efficacy through Literature (꽃차용 꽃의 문헌을 통한 한의학적 효능 분석)

  • Byun, Mi Soon;Seo, Bok Nyeo;Kim, Kiu Weon
    • FLOWER RESEARCH JOURNAL
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    • v.16 no.2
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    • pp.93-101
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    • 2008
  • Research materials used were 55 kinds of flower teas proven in medicinal efficacy based on publications in oriental medicinal science. Efficacy in oriental medical science of the selected plants was classified into 11 groups, exterior-relieving herbs, removing dampness by promoting diuresis herbs, heatclearing herbs, purgative herbs, tonic herbs, qi-activating herbs, herbs as blood-tonics, herbs warming the intestine, qi-regulating herbs, herbs for removing dampness by means of aromatics, and herbs activating blood. Moreover, they were assorted by fever (hot, warm, slightly warm, common, cool, and cold), flavor (sweet, bitter, spicy, sour, and salty), and toxicity (toxic or nontoxic). Generally, flower teas have been known to be drinkable by all people. However, it is important to select proper flower teas considering physical constitution and health condition of the individual. One should be cautious in drinking flower teas containing toxic ingredients and weak people should be prohibited drinking them. Further clinical study on efficacy of flower teas will contribute to commercialization of these teas.

Carcass characteristics of lambs fed diets with increasing levels of crude glycerin

  • Costa, Caio Alves da;Carvalho, Francisco Fernando Ramos de;Guim, Adriana;Andrade, Gilcifran Prestes de;Cardoso, Daniel Barros;Maciel, Michel do Vale;Silva, Gabriela Goncalves da;Nascimento, Andreza Guedes de Oliveira
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.12
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    • pp.1882-1888
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    • 2019
  • Objective: An experiment was conducted to evaluate the effects of increasing levels of crude glycerin (0%, 6%, 12%, and 18%) used as a substitute for corn in lamb feed on the quantitative characteristics of the carcass. Methods: A total of 40 crossbred Santa $In{\hat{e}}s$ lambs that were four months old with a mean initial weight of $21.0{\pm}0.8kg$ were randomly distributed in four treatments with ten replicates. The animals were slaughtered after 66 days of confinement. The effects of crude glycerin as a replacement for corn in the diet of the lambs on the carcass characteristics, commercial cut weight and yield and carcass measurements were studied. Results: There was an increasing linear effect for body weight at slaughter with the replacement of corn by crude glycerin. The dry matter and metabolizable energy intakes, weight of the empty body, hot carcass weight and cold carcass weight showed a quadratic effect, with maximum crude glycerin levels estimated at 10.9%, 9.8%, 10.83%, 11.78%, and 11.35%, respectively. The initial pH was not influenced by the replacement of corn for crude glycerin, while the final pH presented a quadratic effect. The other parameters of the carcass and the weights and yields of commercial cuts were not influenced. There was also no effect of the diets on carcass morphometric measurements, except for the thoracic perimeter and the carcass compactness index, which presented quadratic and linear effects, respectively. Conclusion: Crude glycerin can replace up to 18% of corn because it favours muscle tissue deposition without promoting changes in the main carcass characteristics of lambs.

Spatial Autocorrelation Characteristic Analysis on Bayesian ensemble Precipitation of Nakdong River Basin (낙동강유역 강우의 공간자기상관 특성분석을 통한 베이지안 앙상블 강우 검증)

  • Moon, Soo Jin;Sun, Ho Young;Kang, Boo Sik
    • Proceedings of the Korea Water Resources Association Conference
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    • 2017.05a
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    • pp.411-411
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    • 2017
  • 유역 내 발생하는 강우의 공간적인 분포는 인접성 및 거리에 따라 달라질 수 있다. 공간자기상관 분석은 공간단위(유역 또는 행정구역)의 변수(강수 등)가 주변지역과 갖는 관계를 통해 얼마나 분산되어 있는지 혹은 군집되어 있는지를 판별하는 기법으로 최근 많은 연구에서 활성화 되고 있다. 본 연구에서는 낙동강유역을 대상으로 1980~2000년까지 20개년의 기상청을 통해 수집한 강우자료와 CMIP5(Coupled Model Intercomparison Project Phase 5)에서 제공하는 기후변화 자료 중 가용할 수 있는 20개 모델의 강우를 수집하였다. 기후변화 자료는 정상성 분위사상법으로 지역오차보정을 실시하고 불확실성을 저감하고자 베이지안 모델 평균기법을 통해 새로운 시계열을 생성하였다. 생성된 시계열의 공간적인 분포를 정량적으로 평가하고자 중권역별 공간자기상관 분석을 수행하였다. 대부분의 연구에서는 GIS를 활용하여 정성적으로 강우의 분포를 나타내고 있지만 본 연구에서는 공간단위의 인접성 또는 거리에 따른 척도를 기반으로 공간자기상관을 탐색할 수 있는 Moran's I와 LISA(Local Indicators of Spatial Association)기법을 적용하였다. Moran's I는 전체 연구지역에 대한 관계를 하나의 값으로 보여주는 전역적인 기법이며, LISA는 상대적으로 넓은 지역을 국지적으로 구분하여 특정지역에 대한 Hot spot 및 Cold spot을 통해 공간자기상관 정도를 나타내는 국지적인 기법이다. 두 기법을 적용하기 위하여 인접성 기반의 공간매트릭스를 산정하고 계절별 관측값과 베이지안 앙상블 강우의 Moran's I 및 LISA 분석을 실시하였다. 관측자료와 베이지안 앙상블 강우의 분석결과가 매우 유사하게 나타남으로써 베이지안 앙상블 강우의 공간적인 분포가 관측강우를 충분히 재현하고 있다고 판단된다.

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An Experimental Study on Flame Structure and Combustion Instability Characteristics in Model Gas Turbine Combustor (모형 가스터빈 연소기에서 화염구조와 연소불안정 특성에 대한 실험적 연구)

  • Park, Sung-Soon;Kim, Min-Ki;Yoon, Ji-Su;Yoon, Young-Bin
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2011.04a
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    • pp.445-452
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    • 2011
  • The present work addresses structural characteristics of natural gas flames in a lean premixed swirl-stabilized combustor with an attention focused on the effect of the formation of recirculation zones on the combustion instability. It is known that the recirculation zone plays an important role in stabilizing a turbulent, premixed natural gas flames by providing a source of heat or radicals to the incoming premixed fuel and air. To improve our understanding of the role of recirculation zones, the flame structure was investigated for various mixture velocities, equivalence ratios and swirl numbers. The optically accessible combustor allowed for the application of laser diagnostics, and Particle Image Velocimetry(PIV) measurements was used to characterize the flame structure under both cold flow conditions and hot flow conditions. Dynamic pressures were also measured to investigate characteristics of combustion at the same time. The results indicates that the formation of recirculation zone is strongly related to the occurrence of thermo-acoustic instabilities.

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Analysis on Heart Rate Variability (HRV) Characteristics of Patients with Insomnia during Perimenopause and Postmenopause: A Retrospective Chart Review (불면증이 동반된 여성 갱년기 환자의 심박변이도 특성 분석 : 후향적 차트리뷰)

  • Ahn, Soo-Yeon;Park, Eun-Ji;Lee, Ji-Yeon;Yoo, Jeong-Eun
    • The Journal of Korean Obstetrics and Gynecology
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    • v.30 no.3
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    • pp.54-64
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    • 2017
  • Objectives: The purpose of this study is to demonstrate Heart Rate Variability characteristics of menopausal patients with insomnia. Methods: From March 1, 2014 to June 20, 2017, Heart Rate Variability was measured in 102 menopausal patients who visited Cheonan Korean Medicine Hospital of Daejeon University. We compared accompanying symptoms and Heart Rate Variability values depending on sleep quality in menopausal women. Results: The accompanying symptoms of menopausal patients were as follows: hot flushes (45.1%), tiredness (25.49%), chest discomfort and palpitations (23.53%), headache (17.65%), arthralgia and muscular pain (17.65%), cold sensitivity of hands and feet (15.69%), urinary frequency (14.71%) and anxiety (10.78%). The frequency of chest discomfort and palpitation was significantly higher in the menopausal insomnia group than in normal sleep group. Comparing Heart Rate Variability between two groups, Standard deviation of the NN interval (SDNN), Total Power (TP), and Low Frequency (LF) values were significantly lower in insomnia group. Conclusions: Chest discomfort and palpitations were more frequent in insomnia patients in menopausal women than normal sleep group, and Standard deviation of the NN interval (SDNN), Total Power (TP), Low Frequency (LF) were significantly lower in HRV values.