• Korea-Australia Rheology Journal
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• 제17권1호
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• pp.27-32
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• 2005

We determine the effective viscosity of suspensions with bidisperse particle size distribution by modifying an effective-medium theory that was proposed by Acrivos and Chang (1987) for monodisperse suspensions. The modified theory uses a simple model that captures some important effects of multi-particle hydrodynamic interactions. The modifications are described in detail in the present study. Estimations of effective viscosity by the modified theory are compared with the results of prior work for monodisperse and bidisperse suspensions. It is shown that the estimations agree very well with experimental or other calculated results up to approximately 0.45 of normalized particle volume fraction which is the ratio of volume faction to the maximum volume fraction of particles for bidisperse suspensions.

• 소성∙가공
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• 제13권4호
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• pp.350-358
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• 2004

The effects of alloying elements on microstructural features and mechanical properties in 0.55%C medium carbon steels were investigated. The samples were austenitized at 105$0^{\circ}C$ for 30min. followed by quenching in a salt bath in the temperature range of 500 ~ $620^{\circ}C$. The addition of Cr resulted in the decrease of the volume fraction of pro-eutectoid ferrite and interlamellar spacing in pearlite and the increase of strength. However, the addition of B caused the increase of the volume fraction of pro-eutectoid ferrite. Reduction of area and Charpy impact values were influenced by the combined effect of microstructural features, such as the volume fraction of pro-eutectoid ferrite, interlamellar spacing and the thickness of lamellar cementite in pearlite.

• Journal of Preventive Medicine and Public Health
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• 제37권1호
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• pp.26-36
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• 2004

Objective : To examine the association between hospital procedure volume and treatment outcomes following allogeneic bone marrow transplantation (allo-BMT). Methods : Out of 1,050 patients who received allo-BMTs between 1998 and 2000 in 21 Korean hospitals, 752 with first allo-BMT and complete data were included in this study. Study subjects were divided into the following three groups according to cumulative hospital experience of all-BMTs during the study period: low (<30 cases), medium (30-49) and high ($\geq$50 cases) volume. Patient outcome was defined as early survival at day 100 and one-year survival. Multiple logistic regression analyses were performed to examine the association between hospital experience and survival at day 100 and one year. Results : When the low volume group was defined as the reference group, the adjusted relative risks (RR) of survival at day 100 for the high volume group were 2.46(95% CI, 1.13-5.36) for all patients, 2.61(1.04-6.57) for those with leukemia, and 2.20(0.47-10.32) for those with aplastic anemia. For one-year survival, adjusted RR for the high volume group were 2.52(1.40-4.51) for all patients, 1.99 (1.01-3.93) for leukemia, and 6.50(1.57-26.80) for aplastic anemia. None of the RR for the medium volume group was statistically significant. Patient factors showing significant relationship with survival were donor-recipient relation, human leukocyte antigen matching status, time from diagnosis to transplant, and disease stage. Conclusions : The study results suggest that the cumulative experience of hospitals in providing allo-BMT is positively associated with patient survival.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 INTERNATIONAL SYMPOSIUM ON SOIL & GROUNDWATER ENVIRONMENT
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• pp.195-196
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• 2005

• 한국버섯학회지
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• 제18권4호
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• pp.303-310
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• 2020

꽃송이버섯은 우리나라에서 2000년대 초반부터 재배를 시작하였고, 국내에서는 전라북도농업기술원이 육성한 '너울'이 2016년에 최초로 등록되어 있다. 그러나, 꽃송이버섯에 대한 재배매뉴얼이 없어 여전히 농가마다 자실체 생산성의 차이가 큰 실정이다. 이에 꽃송이버섯 '너울'의 발이조건을 구명하고 안정생산 기술을 개발하고자 배지 pH, 배지함수율, 종균접종량 조건에 따른 연구를 수행한 결과, 재배일수, 수확률과 자실체 중량을 고려한 연중 병당 수량은 pH 3.8 처리구가 363.6 g으로 가장 높게 나타났으나 pH 3.6 조건에서는 수량이 189.5 g으로 급감하는 점, pH 4.0 조건이 배양일수가 짧고 pH 3.8 조건과 비교하여 재배일수가 같으며, 자실체 중량 차이의 유의성이 인정되지 않는 점, 농가에서 활용 시 정밀한 pH 조절이 어려운 점을 고려하여 pH 3.9±1로 조절하여 재배해야 안정생산이 가능할 것으로 판단된다. 아울러 배지함수율을 65%로 조절하고, 배지부피의 4%에 해당하는 액체종균을 접종 후 배양실 내 습도조건을 50% 이하로 설정하면 연중 병당 341.8 g을 생산할 것으로 판단된다.

• 한국자원식물학회지
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• 제30권6호
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• pp.699-706
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• 2017

For rapid production of freesia 'Shiny Gold' shoots by using a bioreactor, several culture conditions were investigated. Young shoots (< 1 cm) obtained from freesia corm section in vitro were used as plant materials for this experiment. As a basic experimental environment, 20 young shoots were inoculated into a 5 L balloon type bubble reactor which contained 1 L 1/2 strength MS medium supplemented with 30 g sucrose (3%), and the aeration was 0.1 vvm (vessel volumes per minute). The bioreactors were placed in a growth room with $23^{\circ}C$ temperature, 60% relative humidity and $60{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ light condition (16 h/8 h, day/night). The concentrations of MS media were set with 1/4, 1/2, 1 strength, medium volume 10, 20, 40%, sucrose concentration 3, 6, 9%, and aeration 0.1, 0.2, 0.4 vvm. After 4 weeks of cultivation, the growth indexes including the fresh and dry weight, and plant height were evaluated. At the same time, the consumption, pH, and EC of medium were estimated 4 weeks after incubating. The best results were achieved when 40 young shoots were incubated in a bioreactor in which 1 L of 1/2 strength MS medium supplemented with 6% sucrose was used for the rapid production of freesia shoots. The shoots were 17 cm in plant height and 1.0 g in fresh weight only 4 weeks after incubation which could be a good plant material suitable for corm enlargement in vitro. No correlation was observed between the growth of freesia shoots and the consumption, pH or EC of medium.

• 대한방사선협회지
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• 제30권1호
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• pp.131-142
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• 2004

In this study, when intravenous contrast medium was injected in spiral CT study, the effects of injection volume, injection rate, injection mode, location and lumen of IV catheter on enhancement of contrast medium in aorta, portal vein and liver parenchym

• 한국문헌정보학회지
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• 제8권
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• pp.157-182
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• 1981

The purpose of present study is to investigate children's attitude toward reading, reading method, reading environment, reading volume, and then to compare the results obtained by sex, area and grade. The tool used in this survey was a questionaire designed specially by the investigator. The questionaire was distributed to 1339 children selected at the descretion of the investigator with due consideration of sex, area(large city, medium city and rural community) and grade (from 2nd grade of primary school to 2nd year of middle school). The results of this study are summerized as follows : 1) Regional difference was observed in respect of the followiug : Awareness on reading, motivation for reading, reading method, activity after reading, number of books collected, reading guidance, how to obtain books to read, monthly reading volume, and reading tendency. 2) Also difference by grade was observed in respcet of the following ; Activity after reading, reading guidance, monthly reading volume and reading tendency. The following conclusions have been made based on the results of the survey: 1) The children's attitude toward reading and reading method may be considered favorable while reading environment is not satisfactory yet. Especially, reading environment of school children in medium cities and rural communities is worse than that of large cities. 2) No difference by sex was observed in respect of attitudes toward reading, reading method, reading environment and reading volume while difference by sex was observed in respect of reading tendency. The followings are recommended based on the results of survey: 1) To establish and carry out a comprehensive program for the improvement of reading environment of the school children in medium cities and rural communities. 2) To improve and substantiate school library facilities and design a proper guidance program to have children utilize school library to the maximum extent. 3) To contemplate on the consolidated measures for reading behavior survey.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1995년도 한국생물과학협회 학술발표대회
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• pp.205.2-205
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• 1995

No Abstract, See Full Text

• 반도체디스플레이기술학회지
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• 제18권4호
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• pp.129-133
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• 2019

In this paper, we developed a system to monitor the storage capacity of suction-type device such as vacuum cleaner or crop harvesters. The monitoring system consists of load cells and a differential pressure sensor which simultaneously monitor the weight and volume of the stock. Since weighing objects stored in storage containers alone cannot fully monitor the level of filling, more accurate monitoring can be achieved by monitoring volume and fusion with weight information. The volume was monitored using a phenomenon in which the flow rate of the inhaled air varies depending on the volume of the object filled in the storage container. In this paper, we developed a system to monitor the storage in three stages: low, medium and high.