• 제목/요약/키워드: volume effects

검색결과 4,213건 처리시간 0.034초

일부 암 종의 수술량과 병원 내 사망률의 관계에서 구조적 복잡성의 조절효과 (Moderating Effect of Structural Complexity on the Relationship between Surgery Volume and in Hospital Mortality of Cancer Patients)

  • 윤경일
    • 보건행정학회지
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    • 제24권4호
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    • pp.380-388
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    • 2014
  • Background: The volume of surgery has been examined as a major source of variation in outcome after surgery. This study investigated the direct effect of surgery volume to in hospitals mortality and the moderating effect of structural complexity-the level of diversity and sophistication of technology a hospital applied in patient care-to the volume outcome relationship. Methods: Discharge summary data of 11,827 cancer patients who underwent surgery and were discharged during a month period in 2010 and 2011 were analyzed. The analytic model included the independent variables such as surgery volume of a hospital, structural complexity measured by the number of diagnosis a hospital examined, and their interaction term. This study used a hierarchical logistic regression model to test for an association between hospital complexity and mortality rates and to test for the moderating effect in the volume outcome relationship. Results: As structural complexity increased the probability of in-hospital mortality after cancer surgery reduced. The interaction term between surgery volume and structural complexity was also statistically significant. The interaction effect was the strongest among the patients group who had surgery in low volume hospitals. Conclusion: The structural complexity and volume of surgery should be considered simultaneously in studying volume outcome relationship and in developing policies that aim to reduce mortality after cancer surgery.

폐스티로폼의 감용방식에 관한 연구 (A Study on the Various Volume Reducing Methods for Wasted EPS Foam)

  • 임중연;최호준;황병복
    • 한국자원리싸이클링학회:학술대회논문집
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    • 한국자원리싸이클링학회 2003년도 추계정기총회 및 국제심포지엄
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    • pp.165-169
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    • 2003
  • Current volume reduction methods for wasted expandable polystyrene (EPS) foam are summarized and compared each other. Wasted EPS foam has not been recycled effectively because of its large volume to weight ratio. This has prevented from its proper recycling because of high cost of transportation to recycling plant. Successful recycling of wasted EPS foam results directly from successful, i.e. economically and environmentally, volume reduction of wasted EPS foam. This paper deals with various methods for volume reduction methods of wasted EPS foam. Five typical methods of volume reduction are introduced and they are compared each other in terms of expected PS properties after volume reduction, cost effectiveness of each process, possible effects on environment caused by the volume reduction process, and possible recycled products. The methods include thermal, solvent, far infrared and mechanical compaction. Comparison in this paper is made mostly in qualitative manner. The focus in this study is concentrated on summarizing and comparing existing methods of volume reduction for wasted EPS foam.

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정적연소기에서 라디칼 유도분사를 이용한 희박혼합기의 연소특성에 관한 연구 (1) (A Study on the Combustion Characteristics of Lean Mixture by Radicals Induced Injection in a Constant Volume Combustor (1))

  • 박종상;이태원;하종률;정성식
    • 한국자동차공학회논문집
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    • 제12권2호
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    • pp.45-53
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    • 2004
  • An experimental study was carried out to obtain the fundamental data about the effects of radicals induced injection on premixture combustion. A constant volume combustor divided to the sub-chamber and the main chamber was used. The volume of the sub-chamber is set up to occupy less than 1.5% of that of whole combustion chamber. Radial twelve narrow passage holes are arranged between the main chamber and the sub-chamber. The products including radicals generated by spark ignition in the sub-chamber will derive the simultaneous multi-point ignition in the main chamber. While the equivalence ratio of pre-mixture in the main chamber and the sub-chamber is uniform. We have examined the effects of the sub-chamber volume, the diameter of passage hole, and the equivalence ratio on the combustion characteristics by means of burning pressure measurement and flame visualization. In the case of radical ignition method(RI), the overall turning time including the ignition delay became very short and the maximum burning pressure was slightly increased in comparison with those of the conventional spark ignition method(SI), that is, single chamber combustion without the sub-chamber. The combustible lean limit by RI method is extended to more ER=0.25 than that by SI method. Therefore the decrease of every emission including NOx and the improvement of fuel consumption is anticipated due to lean burn.

우수저류 및 침투연못 시스템개발 사례연구 - 우수 저류 및 침투 효과를 중심으로 - (A Case Study on Development of Stormwater Retention and Infiltration Pond System)

  • 이재철;윤여진
    • 한국환경복원기술학회지
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    • 제6권4호
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    • pp.52-61
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    • 2003
  • This study was carried out to analyze the effects of stormwater retention and infiltration pond on reduction of flood peak and volume in a experimentally developed ecological pond. The experimental site has 542$m^2$ watershed area, 1,310mm yearly-averaged rainfall. And the area of the retention pond is 60$m^2$, the maximum water depth is 0.5m, the maximum and average storage is 15$m^3$and 9.3$m^3$d. And the area of infiltration pond is 58$m^2$, and the water depth varies 0.2m~0.5m. The monitoring system consists of one rainfall gage, one Parshall flume and acoustic water level gage, two rectangular weirs and acoustic water level gage for discharge gaging, and one data recording unit. Data from ten storm events in total, three storm events in year 2000 and seven storm events in year 2001, were collected. From the data the evaporation rate was achieved with the water balance equation, and the result shows 5.0mm/day in average. The result from the analysis of the effects on reduction of flood peak and volume, is that 14% reduction of flood volume and 15% reduction of flood peak in retention pond and 49% reduction of flood volume in infiltration pond.

음식물쓰레기의 호기성 퇴비화에 있어서 볏짚과 하수슬러지케이크가 미치는 영향에 관한 비교 연구 (Comparison of Effects of Rice Straw and Sewage Sludge Cake on Aerobic Composting of Food Wastes)

  • 박석환
    • 한국환경보건학회지
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    • 제29권1호
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    • pp.43-50
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    • 2003
  • This study was performed to compare the effects of rice straw and towage sludge cake as bulking materials on temperature, pH, weight and volume reduction, porosity, C/N ratio, salinity, and conductivity in aerobic composting of food wastes. Volume ratios of food wastes to rice straw in reactor control, RS-1, RS-2, RS-3 and RS-4 were 4:0, 4:1, 4:2, 4:3 and 4:4, respectively. Weight ratios of food wastes to sewage sludge rake in reactor control, SL-1, SL-2, SL-3 and SL-4 were 4:0, 4:1, 4:2, 4:3 and 4:4, respectively. Reactors were operated for 24 days with 1 hour stirring by 1 rpm and 2 hours aeration per day. The values of pH of food waters, rice straw and sewage sludge cake were 4.39, 7.40 and 5.79, respectively. The lowering of the volume ratio of food wastes to rice straw resulted in the high reaction temperature and the fast weight and volume reduction rates. The lowering of the weight ratio of food wastes to sewage sludge cake resulted in the slow weight and volume reduction rates. C/N ratio in control was larger than that in rice straw containing reactors, and that in rice straw containing reactors was larger than that in sewage sludge cake containing reactors. Salinity and conductivity in reactors were condensed and increased by reaction days.

초소형 점성 펌프의 Wavier-Stokes 해석 (NAVIER-STOKES SIMULATION OF A MICRO-VISCOUS PUMP)

  • 강동진
    • 한국전산유체공학회지
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    • 제11권4호
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    • pp.75-80
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    • 2006
  • Navier-Stokes simulation of the flow in a micro viscous pump is carried out. The micro viscous pump consists of a rotating circular rotor placed in a two dimensional channel. All simulation is carried out by using a finite volume approach, at the Reynolds number of 0.5, to study the performance of the micro viscous pump. Length of channel of the pump is varied to simulate the effects of the pumping load. Numerical solutions show that the net flow of the pump is realized by two counter rotating vortices formed on both sides of the rotor. The volume flow rate of the pump is decreased as length of the channel is increased, while the static pressure difference across the rotor is increased. The static pressure difference across the rotor is observed to be inversely proportional to the volume flow rate as inertia effects are negligibly small. The efficiency of the pump is found to reach a maximum when two counter rotating vortices on both sides of the rotor becomes to merge forming an outer enveloping vortex.

질려자 추출물의 피부 볼륨 증진 및 주름개선 효과 (Skin Volume Augmentation and Anti-wrinkle Effects of Tribulus terrestris Fruit Extract)

  • 김미진;정택규;박현철;윤경섭
    • KSBB Journal
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    • 제31권3호
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    • pp.178-185
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    • 2016
  • Aging of the face is mainly related to the features that are sagging or loss of elasticity of the skin by reducing the volume around the eyes or cheek. Intrinsic aging can be seen to cause thinner dermis, reduction of extracellular matrix and subcutaneous fat. This study was carried out to investigate the skin volume augmentation and anti-wrinkle effects of Tribulus terrestris fruit extract. Skin anti-aging effect of Tribulus terrestris fruit extract was evaluated by using lipid accumulation, expressin of type I procollagen and elastin in preadipocytes and human dermal fibroblasts. Tribulus terrestris fruit extract augmented preadipocytes differentiation about 56% at 100 µg/mL. The type I procollagen and elastin were increased about 35% and 25% by treatment 20% Tribulus terrestris fruit extract, respectively. The clinical study also showed that skin sagging, skin elasticity, and dermal density improved without adverse effect following 4 week application of cream containing 2% Tribulus terrestris fruit extract. We suggest that Tribulus terrestris fruit extract can have the good possibility as skin volume augmenting, skin elasticity and wrinkle improving agent.

레이저 유도 백열법을 이용한 화염 내부 매연 농도 측정 (Measurements of Soot Volume Fraction Using Laser Induced Incandescence)

  • 이승;이상협;이병준;한재원
    • 대한기계학회논문집B
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    • 제24권5호
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    • pp.725-732
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    • 2000
  • Laser induced incandescence (LII) method is frequently used to measure soot volume fraction in flames. In this study, experiments were performed to measure soot volume fraction in coaxial diffusion flame using LII method and calibrated with laser scattering/extinction method. The effects of laser intensity (>$1{\times}10^8W/cm^2$), laser wavelength (532nm, 1064nm) and detection wavelength (400nm, 600nm) on the LII signal were investigated. On the range of $4{\times}10^8{\sim}8{\times}10^8W/cm^2$ there were no effects of laser intensity on LII signal. Except these ranges, LII signal was increased with laser intensity. For the long gate width, the LII signals of the higher laser intensity (>${\vartheta}(GW/cm^2)$) cases had better correlation with soot volume fraction which were measured by laser extinction method compared with lower laser intensity cases. The errors of 2-dimensional cases at the calibration height were approximately 50% regardless of laser wavelength.

삼화탕(三化湯)이 중간대뇌동맥 결찰로 유발된 뇌허혈에 미치는 영향 (The Effects of Samwha-tang Extracts on Reversible Forebrain Ischemia Experimentally Induced from the Occlusion of Middle Cerebral Artery)

  • 정승현;박인식;신길조;이원철;김동은
    • 대한한방내과학회지
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    • 제22권2호
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    • pp.127-134
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    • 2001
  • The purpose of this investigation is to evaluate the effects of Samwha-tang(三化湯) Extracts on reversible forebrain ischemia experimentally induced from the occlusion of middle cerebral artery. The volume of cerebral ischemia, the volume of cerebral edema, and the change of pyramidal neuron of the CA1 area in hippocampus through light microscopy were investigated. we obtained the following results. The volume of the control group, which had ischemic damage was 21%, and the volume of the sample group, which had ischemic damage, was 16%. The ratio of the volume of the right/left hemisphere was 117.2 in the control group, and 108.8 in the sample group. Also, the light microscopy revealed that the pyramidal cells of CA1 area in hippocampus had many damages like changes into discontinuous and unsystematic forms. But, in the sample group, the cells were less damaged compared with the control group.

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정상체중인과 비만인의 음료와 컵 색상에 따른 인지량의 차이에 관한 연구 (Difference in Volume Perception According to Beverage or Cup Color in Normal Weight and Obese College Students)

  • 이명옥;홍지원;장은재
    • 대한영양사협회학술지
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    • 제19권1호
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    • pp.25-33
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    • 2013
  • We examined the perception of volume in college students with a normal weight versus those students with obesity. College students were divided into a normal weight group (<23 body mass index, n=121) and an obese group (${\geq}23$ body mass index, n=110), The perception of volume was measured under different beverage colors (colorless, black, yellow, and blue) and cup colors (colorless, black, yellow, and blue) containing the same amount of liquid (150 ml). We found that the normal weight group perceived significantly more liquid in a cup with a blue beverage versus a colorless one. The obese group perceived significantly more liquid in a cup with a yellow or blue beverage versus a colorless one. In terms of cup color, the normal weight group perceived significantly more liquid in a black color cup compared to a blue color cup. However, there were no differences in perceived volume according to the color of cup among the obese group. There were no significant differences in the perceived volume between the normal and obese group under all conditions tested. In conclusion, beverage and cup color effects volume perception in normal weight students, while only beverage color effects volume perception in obese students. Therefore, controlling, the color of beverages and cups may help to control the consumption of drinks.