• 제목/요약/키워드: Ratio Test

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뇌졸중의 위험요인에 대한 환자-대조군연구 -과거병력, 생활습관, 혈청지질 및 비만요인을 중심으로- (The Case-Control Study on the Risk Factors of Stroke in Korean Adults -Past Medical History, Life-Style Factors, Serum Lipid Level, Anthropometric Indices-)

  • 고성규;정용수;박경훈;부송아
    • 대한한방내과학회지
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    • 제22권3호
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    • pp.423-430
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    • 2001
  • Objects: The purpose of this case-control study was done to examine the relationship between stroke prevalence and the anthropometric indices(body mass index(BMI), modified Broca's method(Broca's index), waist circumference(WC), waist-hip ratio(WHR)), dyslipidemia, past medical history(heart disease, hypertension, diabetes mellitus(DM)), life-style factors(smoking, drinking) in Korean adults. Methods : The study group consisted of neurologically confirmed 116 stroke patients as the case group and 116 non-stroke patients as control group. Obesity were defined as $BMI{\geq}25kg/m^2,\;Broca's\;index{\geq}30%$, WC >94cm in male and WC >80cm in female, $WHR{\geq}0.9$ in male and $WHR{\geq}0.8$ in female. Oyslipidemia were defined as total $cholesterol{\geq}200mg/dl,\;triglyceride{\geq}200mg/dl,\;HDL-cholesterol {\leq}35mg/dl,\;LDL-cholesterol{\geq}160mg/dl$. Information on life-style factors and past medical history was obtained from personal interview. The analysis of the data was done by means of chi-square test(Pearson's chi-square test, Fisher's exact test) and student t-test. Results: The results were as follow. In the study group: Hypertension had a 4:05 odds ratio, Broca's $index{\geq}30%$ had a 1.98 odds ratio, WC >94cm in male had a 2.17 odds ratio, WC >80cm in female had a 2.80 odds ratio, $WHR{\geq}0.9$ in male had a 4.66 odds ratio, $WHR{\geq}0.8$ in female had a 5.35 odds ratio, but heart disease, DM, life-style factors, serum lipid and 8MI had no direct relationship with odds ratio(nonsignificant). By student t-test, risk factors for stroke were found to be total cholesterol(p=0,025), LDL-cholesterol(p=0.013), WC(p=0.000) and WHR(p=0.000). Conclusions: This study suggests that people should be advised to control hyperlitension, hyperlipidemia and obesity since these carry a risk of stroke.

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Al 2024-T3재의 Crack Opening Point의 평가에 관한 연구 (A Study on Evaluation of Crack Opening Point in Al 2024-T3 Material)

  • 최병기;장경천
    • 한국안전학회지
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    • 제19권2호
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    • pp.16-20
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    • 2004
  • This paper aims to analyze fatigue fracture mechnisms with high strength aluminum alloys, which are widely used in vehicles or airplanes to prevent accidents. Usefulness of the crack opening point was proposed by using an effective stress intensity facor when evaluating the fatigue crack propagaion rate. Therefore an exact crack opening ratio can be measured for a more exact fatigue crack propagation rate. It is found that the fatigue crack propagation rate was valid within the range of experimentation as an effective stress intensity factor. Summarizing the results are as follows in this paper ; (1) It is found that the value of the crack opening ratio is constant at the rear of the specimen, U'=0.25 at the crack mouth and U'=0.45 at the crack tip, respectively regardless of the stress ratio. (2) The crack opening ratio is different according to measurement locations. The crack opening ratio value was measured at the crack mouth by a clip gage or measured behind the specimen by a strain gage. It is found that the crack opening ratio value is more accurate that any other measuring test for evaluating the crack propagation ratio test by effective stress intensity factor.

가변 핵심 대역 하향 표본화 비를 가진 MPEG USAC 성능 평가 (A Performance Evaluation of the MPEG USAC with Variable Core-Band Down-Sampling Ratio)

  • 이재화;김인철
    • 방송공학회논문지
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    • 제18권1호
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    • pp.106-114
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    • 2013
  • 본 논문에서는 내부 표본화 주파수와 핵심 대역 하향 표본화 비의 조정이 MPEG USAC의 전체 성능에 끼치는 영향을 다룬다. 여기서 내부 표본화 주파수는 실제 부호화될 때의 내부적인 표본화 주파수를 말한다. 핵심 대역 하향 표본화 비는 전체 부호화 대역폭에 대한 핵심 대역폭의 비를 나타낸다. 성능은 6개의 실험 음원에 대해 10명이 참가한 MUSHRA 검사를 통해 평가되었다. 실험에서는 기존의 1/2에 비해 1/3 혹은 1/4의 핵심 대역 하향 표본화 비를 사용하면 저전송률에서 부호화 성능을 향상시킬 수 있음을 보였다.

고강도 알미늄 합금재에 있어서 크랙열림점 평가에 관한 연구(I) (A Study on Evaluation of Crack Opening Point in High Strength Aluminum Alloy(I))

  • 최병기
    • 오토저널
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    • 제15권1호
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    • pp.100-106
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    • 1993
  • This paper aims to synthesize the research on fatigue fracture mechanisms of high strength aluminum alloys which are widely used in motorcars or airplanes to prevent accidents. To measure the data of crack opening ratio, the same materials and method are used for evaluating the fatigue crack propagation rate as an effective stress intensity factor. But, many researchers have brought different results. An exact crack opening ratio was, therefore, proposed for getting a more accurate fatigue crack propagation rate. The main conclusions obtained are as follows. (1) As a result of the fatigue test, the value of the crack opening ratio is the same regardless of the stress ratio. (2) The value of crack opening ratio is different according to the measuring point. After measuring the crack propagation rate by using an effective stress intensity factor, the crack opening ratio value measured at the crack mouth by a clip gage, or measured rear of the specimen by a strain gage is more accurate than that by any other measuring test.

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셔츠와 넥타이의 톤 온 톤 배색 면적비 변화에 따른 조화감 비교 (A Comparative of the Harmany of Tone on Tone Coloration according to Transformation of Color Area-Ratio in Shirt and Necktie)

  • 임지영
    • 한국의류산업학회지
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    • 제9권2호
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    • pp.138-144
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    • 2007
  • The purpose of this research was to compare the harmony of tone on tone coloration according to transformation of color area-ratio in shirt and necktie. The respondents were asked to evaluate 48 stimuli of the shirt and necktie with the coloration of the shirt/necktie, the necktie/shirt was separately compounded to be 4 tones such as vivid, light, dull, dark. The subjects were 288 female undergraduate students. The data was analyzed by using SPSS program. Analysis methods were ANOVA, LSD test and t-test. The results of each can be summerized as follows. As to the red, combination of v-lt made a difference in the harmony of coloration according to the transformation of color area-ratio. As to the blue, combination of v-lt, v-dk, lt-d made a difference in the harmony of coloration according to the transformation of color area-ratio. As to the purple, v-lt, v-d was evaluated as harmonized coloration regardless of area-ratio by both male and female students. As to the green, v-lt, lt-d was evaluated as harmonized coloration regardless of area-ratio by both male and female students.

고온 고압 분위기 조건에서 바이오 디젤과 DME의 혼합비에 따른 분무특성에 관한 연구 (An Experimental Investigation on Spray Behavior of Biodiesel and DME on Blended Ratio in High Temperature and Pressure Ambient Conditions)

  • 방승환;전문수;이창식
    • 한국분무공학회지
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    • 제15권1호
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    • pp.17-24
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    • 2010
  • The objective of this work is to analyze the macroscopic behavior of spray and injection characteristics on the DME blended biodiesel at different mixing ratios by using spray visualization and injection rate measurement system. The spray images were analyzed to a spray tip penetration, a spray cone angle and a spray area distribution at various mixing ratio of DME by weight. The influence of different injection pressure and ambient pressure on the fuel spray characteristics are investigated for the various injection parameters. In order to analyze the injection characteristics of test fuels, the fuel injection rate is measured at various blending ratio. The variation of viscosity of the blended fuel by the mixing of DME fuel shows the improved effect of spray developments. Also, it was found that the injection quantities of high blended ratio were larger than that of lower blended fuel. Also, higher blending fuel showed a faster evaporation than that of mixing ratio of test fuel because kinetic viscosity was changed by blending ratio.

LANSAT TM자료에 의한 광화대조사 응용기법개발 (Remote Sensing Application for the Mineralized Zone Using Landsat TM Data)

  • 姜必鍾;智光薰;曺民肇;崔映燮;Choi, Young Sup
    • 대한원격탐사학회지
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    • 제2권2호
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    • pp.79-94
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    • 1986
  • TM data, which have better resolution in spatial and spectral than MSS data, were used for this study, and several Image Processing Techniques (IPT) were examined for finding the best IPT to fit to lineament extraction and mineralized zone mapping. The Ryeongnam area was selected as test area, because the area is one of major mineralized zones in Korea and its hydrothermal alteration zone is wider and deeper than other areas. The spatial filtering method is most optimum one for limeament extraction: that is, the directional spatial filtering is most efficient to detect N-S, E-W direction lineaments on the image, and the high boost filtering can be applied for mapping all direction lineaments. The ratio method was selected for detecting altered zone. It is possible to make several tens combinations in ratio with 7 bands of TM data, but considering spectral characteristics of each band of TM to the geological meterials and vegetation, the band 4/band 3(A), band 5/band 7(B), and B/A ratio methods were chosen among them. The 5/7 ratio image did not show clearly the altered area due to noise from vegetation cover, so the 4/3 ratio imae was used for trying to decrease the effect of vegetation. As a result the B/A ratio image showed quite nicely the altered zone of the test area. In conclusion, the spatial filtering is the best image processing techniques for lineament mapping, and the B/A ratio image in TM data is useful for the mineralized zone mapping.

수평 T형 증발관내 2상류의 유량분배 및 압력강하 특성 (Characteristics of T-phase flow distribution and pressure drop in a horizontal T-type evaporator tube)

  • 박종훈;조금남;조홍기
    • 설비공학논문집
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    • 제11권5호
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    • pp.658-668
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    • 1999
  • The objective of the present study is to investigate the effect of experimental parameters on the hydrodynamic characteristics in a horizontal tee-type evaporator using R-22. The experimental apparatus consisted of an unheated tee-type test section, a liquid-vapor separator, a preheated, mass flow meters, a plate heat exchanger, pump, and other measurement devices. The experimental parameters were mass flux(500 and 600kg/$m^2$s), inlet quality(0.1~0.3) and separation ratio(0.3~0.7). Absolute pressure at the inlet of the test section was 0.652 MPa. The branch-to-inlet inner diameter ratio was 0.61. Pressure gradient at the branch section was larger than that at the run section at the same separation ratio. Pressure drop per unit length increased at the run section and decreased at the branch section as the separation ratio increased. Pressure drop predicted by the separated flow model agreed with experimental data within -35 to +16%. Generally, predicted values showed similar trend with the data. Mass flow ratio of vapor refrigerant was affected by the inlet quality more than the mass flux.

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The Impact of Operating Cash Flows on Financial Stability of Commercial Banks: Evidence from Pakistan

  • ELAHI, Mustahsan;AHMAD, Habib;SHAMAS UL HAQ, Muhammad;SALEEM, Ali
    • The Journal of Asian Finance, Economics and Business
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    • 제8권11호
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    • pp.223-234
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    • 2021
  • This study aims to examine whether operating cash flows influence banks' financial stability in Pakistan. The study employed annual panel data collected from annual reports of 20 commercial banks listed on the Pakistan Stock Exchange for the year 2011 to 2019. Free cash flow yield was taken as the dependent variable while cash flow ratio was selected as the independent variable, and net interest margin, income diversification, asset quality, financial leverage, the cost to income ratio, advance net of provisions to total assets ratio, capital ratio, financial performance, breakup value per share and bank size were taken as control variables. The study performed ordinary least square technique, random and fixed effects models, Hausman test, Lagrange multiplier test, descriptive and correlation analysis. Results showed that operating cash flows and net interest margin significantly and positively influenced banks' financial stability while the cost to income ratio and advances net of provisions to total assets ratio significantly and negatively associated with banks' financial stability. To improve financial stability, banks should become more cost-effective and enhance their liquidity levels by lowering lending activities. In the future, it would be useful to compare commercial and investment banks, also Islamic and conventional banks in the same research setting.

중.노년층에서 연령증가에 따른 영양소 및 식품섭취의 양적, 질적 변화에 대한 종단적 연구 (A Longitudinal Study on the Change of Nutrients and Food Consumption with Advance in Age among Middle-aged and the Elderly)

  • 김인숙;서은아;유현희
    • 대한지역사회영양학회지
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    • 제4권3호
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    • pp.394-402
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    • 1999
  • The purpose of this study is to investigate diet quality and changes in nutrient and food intake with increase in age. Subjects were 69 patients(28 males, 41 females) living in Jeon-ju city, over middle-aged, and they were the same patients studied 4-7 years ago in a previous study. Dietary survey with one day 24-hour recall method was used. Energy, calcium, vitamin A and vitamin B$_2$intakes were lower than the RDA and vitamin C was in excessive status in pre-test and post-test. In food groups examrned, the consumption of potatoes, beans, vegetables, seaweeds, beverages, seasonings, oils, fish & shells and milks was increased amount than 4-7 years before but the consumption of cereals(p<0.01), sugars, seeds, fruits, processed food, meats and eggs was decreased. Diet quality was assessed by %RDA, nutrient adequacy ratio(NAR), mean adequacy ratio(MAR), dietary diversity score(DDS), meal balance and food group pattern. In %RDA, those proportion of appropriate intake in post-test in were higher than those in pre-test. For most nutrient except vitamin A, the levels of NAR in post-test were higher than in pretest. The MAR, an index of overall dietary quality, was 0.77 for pre-test and 0.83 for post-test(p<0.05). When we counted the major food groups consumed(KDDS), 62.3% of subjects had a KDDS of 3 in pre-test and 42.0% of subjects had a KDDS of 4 in post-test. Based on these results, in terms of variety and balance, total diet quality was improved with advancing of age.

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