• 제목/요약/키워드: volume effect

검색결과 5,907건 처리시간 0.052초

두경부 IMRT 및 VMAT 시 체적 감소가 전산화치료계획에 미치는 영향 (The Effect of Volume Reduction on Computed Treatment Planning during Head and Neck IMRT and VMAT)

  • 엄기천;김가중;백금문
    • 대한방사선기술학회지:방사선기술과학
    • /
    • 제46권3호
    • /
    • pp.239-246
    • /
    • 2023
  • In this study, we assessed the effect of reduction of tumor volume in the head and neck cancer by using RANDO phantom in Static Intensity-Modulated Radiation Therapy (S-IMRT) and Volumetric-Modulated Arc Therapy (VMAT) planning. RANDO phantom's body and protruding volumes were delineated by using Contour menu of Eclipse™ (Varian Medical System, Inc., Version 15.6, USA) treatment planning system. Inner margins of 2 mm to 10 mm from protruding volumes of the reference were applied to generate the parameters of reduced volume. In addition, target volume and Organ at Risk (OAR) volumes were delineated. S-IMRT plan and VMAT plan were designed in reference. These plans were assigned in the reduced volumes and dose was calculated in reduced volumes using preset Monitor unit (MU). Dose Volume Histogram (DVH) was generated to evaluate treatment planning. Conformity Index (CI) and R2 in reference S-IMRT were 0.983 and 0.015, respectively. There was no significant relationship between CI and the reduced volume. Homogeneity Index (HI) and R2 were 0.092 and 0.960, respectively. The HI increased when volume reduced. In reference VMAT, CI and R2 were 0.992 and 0.259, respectively. There was no relationship between the volume reduction and CI. On the other hand, HI and R2 were 0.078 and 0.895, respectively. The value of HI increased when the volume reduced. There was significant difference (p<0.05) between parameters (Dmean and Dmax) of normal organs of S-IMRT and VMAT except brain stem. Volume reduction affected the CI, HI and OAR dose. In the future, additional studies are necessary to incorporate the reduction of the volume in the clinical setting.

n-Alkyl amine 鹽酸鹽의 水溶液 中에서의 apparent 및 partial molal volumes에 관한 硏究 (A study on the apparent and partial molal volumes of n-Alkyl amine hydrochloride in water)

  • 운상기
    • 대한화학회지
    • /
    • 제13권2호
    • /
    • pp.121-129
    • /
    • 1969
  • n-Alkylamine hydrochlorides $C_nH_{2n+1}NH_3CI$에서 n=0에서 n=4 까지 이르는 低分子量 同族體의 apparent molal volume {\phi}\nu$ 및 partial molal volume $V^{\circ}$을 30$^{\circ}C$水溶液에서 測定하엿다 아민산의 濃度는 0.01M에서 0.3M까지 , 密度測定은 浮力法(Float method)를 適用하여 少數點 以下 5位까지 取하였다. 實驗結果 同族體의 分子量이 一定量 $CH_2$식 增加함에 따라 $V^{\circ}$값이 規則的인 差로서 增加한다는 事實이 觀測되었다. 또한 濃度增加함에 따른 {\phi}\nu$ 變化는 共通的으로 直選的이고 limiting slope는 positive이며 比較的 理論値에 가까왔다. 共通anion인 鹽素이온 $CI^-$의 partial molal volume, $V^{\circ}$$CI^-$은 18.6ml $mole^{-1}$으로 他硏究者들의 date와 大體的으로 一致하였다. {\phi}{\nu}$ 값의 變化로 보아 이온의 hydrophobic effect와 change effect는 거의 競合狀態이나 charge effect 곧 electrostriction effect가 優勢를 보였다.

  • PDF

환자 대장 CT 프로파일을 이용한 전자적 장세척 방법 (An Electronic Colon Cleansing Method using a Patient Colon CT Profile)

  • 김한별;김동성
    • 한국정보과학회논문지:소프트웨어및응용
    • /
    • 제35권8호
    • /
    • pp.493-500
    • /
    • 2008
  • 가상 대장 내시경을 위해서 환자 대장 CT 프로파일을 이용한 전자적 장세척 방법을 제안한다. 제안된 방법은 관강 영역을 cubic seeded region growing(SRG) 방법을 이용하여 추출하고, 이에 인접한 tagged material(TM)을 제거한다. TM의 경계에서 Air-TM의 partial volume(PV) 효과로 발생한 찌꺼기를 제거하고, TM-soft tissue(ST)의 PVE에 의해서 제거된 ST는 환자 CT 프로파일을 이용해서 복원한다. 제안된 방법을 16명의 가상 내시경 환자 CT 데이타에 적용해서 임상의의 주관적인 평가와 computer-aided diagnosis(CAD)의 정량적 평가에서 매우 고무적인 결과를 획득했다.

Fe-26Mn-4Co-2Al 제진합금의 인장강도에 미치는 냉간가공의 영향 (Effect of Cold Working on the Tensile Strength of Fe-26Mn-4Co-2Al Damping Alloy)

  • 강창룡;김성휘;정규성
    • 동력기계공학회지
    • /
    • 제20권6호
    • /
    • pp.46-50
    • /
    • 2016
  • This study was carried out to investigate the effect of cold working on the tensile strength of Fe-26Mn-4Co-2Al damping alloy. ${\alpha}^{\prime}$ and ${\varepsilon}$-martensite were formed by cold working, and martensite was formed with the specific direction and surface relief. With the increasing degree of cold rolling, volume fraction of ${\alpha}^{\prime}$-martensite was increased, whereas the volume fraction of ${\varepsilon}$-martensite was decreased after rising to maximum value at specific lever of cold rolling. Tensile strength was linearly increased with an increasing of degree of cold rolling. Tensile strength was strongly affected to the volume fraction of ${\varepsilon}$-martensite formed by cold working, but the effect of volume fraction of ${\varepsilon}$-martensite on the tensile strength was not observed.

Effect of the Pore Structure of Concrete on the Compressive Strength of Concrete and Chloride Ions Diffusivity into the Concrete

  • Kim, Jin-Cheol;Paeng, Woo-Seon;Moon, Han-Young
    • 콘크리트학회논문집
    • /
    • 제15권2호
    • /
    • pp.345-351
    • /
    • 2003
  • The transport characteristics of deleterious ions such as chlorides depend on the pore structures of concrete and are the major factors in the durability of concrete structures in subjected to chloride attack such as in marine environments. In this paper, the effect of the pore structure on compressive strength and chloride diffusivity of concrete was investigated. Six types of concretes were tested. The pore volume of concrete containing mineral admixtures increased in the range of 3∼30nm due to micro filling effect of hydrates of the mineral admixtures. There was a good correlation between the median pore diameter, the pore volume above 50nm and compressive strength of concrete, but there was not a significant correlation between the total pore volume and compressive strength. The relationship between compressive strength and chloride diffusivity were not well correlated, however, pore volume above 50nm were closely related to the chloride diffusion coefficient.

액적 체적이 증발 특성에 미치는 영향에 관한 수치해석 연구 (Effect of the Droplet Volume on the Evaporative Characteristics of Sessile Droplet)

  • 정찬호;이형주;김홍석;이성혁
    • 한국분무공학회지
    • /
    • 제26권2호
    • /
    • pp.88-95
    • /
    • 2021
  • This study aims to investigate the influence of the droplet volume on the evaporation characteristics of the sessile droplet. In particular, the effect of the free convection in the vapor domain on the evaporation rate was analyzed through the numerical simulation. The commercial code of the ANSYS Fluent (V.2020 R2) was used to simulate the heat transfer in the liquid-vapor domain. Moreover, we used the diffusion model to estimate the evaporation rate for the different droplet volume under the room temperature. It was found that the evaporation rate significantly increases with the droplet volume because of the larger surface area for the mass transfer. Also, the effect of free convection on the evaporation rate becomes significant with an increment of droplet volume owing to the increase in the droplet radius corresponding to the characteristic length of the free convection.

스포츠화시장의 구매시점효과에 관한 기술적 연구 -요일효과와 월중효과를 중심으로- (A Descriptive Study on the Purchase Timing Effect in Athletic Shoes -Focused on Day-of-the-week Effect and Intra-month Effect-)

  • 이민호;황선진;곽영식
    • 한국의류학회지
    • /
    • 제36권4호
    • /
    • pp.422-431
    • /
    • 2012
  • The influence of a marketing mix on the consumer purchasing process is well documented in academic fields; however, studies of when consumers purchase fashion brands or products in terms of the day-of-the-week effect and 10-days-of-the-month effect on various channels to a given brand in practice are limited in the fashion industry. This study empirically describes the purchase timing behavior for athletic shoes using daily sales data from a domestic brand in Korea from January in 2006 to December in 2010. The results show that Saturday and Sunday have significantly higher sales than weekdays. In addition, the first and third 10-days-of-the-month yield a higher sales volume than the second 10-days-of-the-month. The department store's sales volume (compared with discount and franchised stores) was higher in the first 10-days-of-the-month; however, the discount and franchised stores have a higher sales volume in the second 10-days-of-the-month. Three store types have no significant differences in sales volume for the third 10-days-of-the-month. Based on the results, in practice, marketers for a specific domestic brand can develop a new marketing expenditure plan, store supply plan, and cash-in and cash-out plan to maximize profits. This research can introduce constructs such as purchase timing distribution, the day-of-the-week effect, and the ten-days-of-the-month effect for the fashion industry.

증편 구조에 미치는 쌀 단백질의 영향 (Effect of Rice Protein on the Network Structure of Jeung-Pyun)

  • 이해은;이아영;박주연;우경자;한영숙
    • 한국식품조리과학회지
    • /
    • 제20권4호
    • /
    • pp.396-402
    • /
    • 2004
  • 증편의 sponge상의 망상구조에 쌀 단백질의 영향을 조사하기 위하여 증편제조시 주원료인 쌀 단백질을 분리하고 증편 발효시 그 변화를 살펴보았으며 protease 첨가가 증편의 점도 및 부피에 미치는 영향을 살펴보았다. 또한 쌀 전분에 단백질을 첨가하여 증편의 점도 및 부피에 미치는 영향을 살펴본 결과 쌀 단백질이 증편의 부피 팽창에 영향을 주는 것으로 생각되었다. 쌀 및 증편 반죽에서는 SDS 가용성 단백질 함량이 밀가루와 비교해 높게 나타났으며 발효시간에 따른 단백질 추출량은 큰 변화가 없었다. 그러나 증편반죽의 시간별 FPLC패턴은 발효시간에 따라 저분자 peak가 감소하여 고분자화함을 알 수 있었다. 단백질 분해효소 protease를 첨가하여 본 결과 증편의 점도 및 부피는 현저히 감소하였고 쌀 전분에 단백질을 첨가하여 증편을 재구성한 결과, 점도, 부피는 증가하는 것으로 나타나 증편내에서 쌀 단백질이 증편의 부피 내지는 조직감 형성에 크게 영향을 미치는 것으로 생각되어진다.

팔정산가미방(八正散加味方)이 Glycerol로 유발된 흰쥐의 신(腎) 손상에 미치는 영향

  • 윤왕수;소경순;정찬길
    • 대한약침학회지
    • /
    • 제10권1호통권22호
    • /
    • pp.23-36
    • /
    • 2007
  • Objective : We performed this study in order to investigate the effects of Paljeongsan-gamibang(八正散加味方) on the renal failure. Methods : We injected 8ml/kg of 50% glycerol on the rats. And then administered Paljeongsan-gamibang extract ; 209mg/200g/day to sample group during 3 days and observed the body temperature, urine volume, stool volume and the levels of creatinine, glucose, inorganic phosphorus, Na+, K+, Cl-, threonine, tyrosine in blood and creatinine, glucose, threonine, tyrosine in urine. Results : 1, The sample group administered Paljeongsan-gamibang showed a suppressive effect of body temperature, an improving effect in capability of concentrating urine at convoluted tubule and showed an increasing effect of stool volume. 2. The sample group administered Paljeongsan-gamibang showed a lowering effect in creatinine level in blood and showed an increasing effect in the levels of inorganic phosphorus, Na+, K+, Cl-, threonine and tyrosine in blood. 3. The sample group administered Paljeongsan-gamibang showed an increasing effect in creatinine level in urine and showed a lowering effect in the levels of glucose, inorganic phosphorus, threonine and tyrosine in urine. Conclusions : Conclusively, Paljeongsan-gamibang was recognized to have a curative effect against the damage of rat kidney induced by 50% glycerol, especially to improve the capability of reabsorption in proximal convoluted tubule.

굴 산지시장의 위판량과 가격관계 (The Volume and Price Relationship of the Oyster Market in Producing Area)

  • 강석규
    • 수산경영론집
    • /
    • 제32권1호
    • /
    • pp.1-14
    • /
    • 2001
  • The research on the price-volume relation in the market is very important because it examines into regular phenomenon revealed by market participants including producers and middlemen. The purpose of this study is to investigate the relationship between price and trading volume in the oyster producing market. In order to accomplish the purpose of this study, the contents of empirical analysis include the time series properties of price and trading volume, the short-term and long-term relationships between price and trading volume, and the determinants of trading volume. The data used in this study correspond to daily price and trading volume covering the time period from January 1998 to April 2001. The empirical results can be summarized as follows : First, price and trading volume follow random walks and they are integrated of order 1. The first difference is necessary for satisfying the stationary conditions. Second, price and trading volume are cointegrated. This long-run relationship is stronger from trading volume to price. Third, error correction model suggests that feedback effect exists in the long-run and that price tends to lead trading volume by about five days in the short run, that is, to be required period by digging, conveying, and peeling oystershell for selling oyster. Fourth, price and price volatility is a determinant of trading volume. In particular, trading volume is a negative function of price. It is believed that the conclusion drawn from this study would provide a useful standard for the policy makers in charge of reducing the oyster price volatility risk caused by trading volume(selling quantities).

  • PDF