• Nuclear Engineering and Technology
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• 제46권1호
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• pp.93-100
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• 2014

The paper deals with the application of radio isotopic non-destructive technique in the characterization of two industrial grade anion exchange resins Indion GS-300 and Indion-860. For the characterization of the two resins, $^{131}I$ and $^{82}Br$ were used as tracer isotopes to trace the kinetics of iodide and bromide ion-isotopic exchange reactions. It was observed that the values of specific reaction rate ($min^{-1}$), amount of iodide ion exchanged (mmol), initial rate of iodide ion exchange (mmol/min) and log $K_d$ were calculated as 0.328, 0.577, 0.189 and 19.7 respectively for Indion GS-300 resin, which was higher than the respective values of 0.180, 0.386, 0.070 and 17.0 calculated for Indion-860 resins when measured under identical experimental conditions. Also at a constant temperature of $40.0^{\circ}C$, as the concentration of labeled iodide ion solution increases 0.001 M to 0.004 M, the percentage of iodide ions exchanged increases from 75.16 % to 78.36 % for Indion GS-300 resins, which was higher than the increases from 49.65 % to 52.36 % compared to that obtained for Indion-860 resins. The overall results indicate that under identical experimental conditions, Indion GS-300 resins show superior performance over Indion-860 resins.

• Nuclear Engineering and Technology
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• 제55권6호
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• pp.2206-2214
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• 2023

The existing wet reconversion processes for the recovery of scraps generated in manufacturing of nuclear fuel are complex and require several unit operation steps. In this study, it is attempted to simplify the recovery process of high-quality fuel-grade UO₂ powder. A novel wet reconversion process for uranyl nitrate hexahydrate solution is suggested by using a newly developed pulsed fluidized bed reactor, and the resultant chemical characteristics are evaluated for the intermediate ammonium uranate hydrate product and subsequently converted UO₂ powder, as well as the compliance with nuclear fuel specifications and advantages over existing wet processes. The UO₂ powder obtained by the suggested process improved fuel pellet properties compared to those derived from the existing wet conversion processes. Powder performance tests revealed that the produced UO₂ powder satisfies all specifications required for fuel pellets, including the sintered density, increase in re-sintered density, and grain size. Therefore, the processes described herein can aid realizing a simplified manufacturing process for nuclear-grade UO₂ powders that can be used for nuclear power generation.

• 대한간호학회지
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• 제38권1호
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• pp.83-91
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• 2008

Purpose: The purpose of this study was to test the validity of a modified clinical performance examination (CPX) for preclinical students in nursing. Method: 70 nursing students in their second semester of the junior year at C University participated in CPX. Scenarios and checklists were developed by our research team from September to October 2005. Six stations were organized. Evaluation included physical examination of a patient with lung cancer, education on usage of a metered dosage inhaler, and lobectomy postoperative care. Students were randomly assigned to a station. Result: There was a difference in the CPX scores according to stations. The agreement of scoring between trained faculty members and SPs was more than moderate (r=.647). The correlation between the CPX score and the average grade in the previous semester and between the CPX score and the average grade of a paper and pen test of the pulmonary system of adults was low (r=.276; r=.048). Conclusion: Traditional CPX is generally recommended, however, modified CPX is appropriate for preclinical students in the current Korean Nursing school setting if there are additional scoring systems to balance the testing level at each station.

• Journal of Animal Science and Technology
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• 제59권3호
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• pp.6.1-6.6
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• 2017

Background: This study was aim to observe the effects of feeding mixed local hay (MH) consisted of 55% orchard grass (Dactylis glomerata L.), 35% tall fescue (Festuca arundinacea) and 10% red clover (Trifolium pratense) to Hanwoo steers on performance, carcass characteristics and meat quality (longissimus thoracis) compared with feeding imported timothy hay (TH) and local rice straw (RS). Results: Although no significant effects were found on animal performance and carcass yield grade, the carcasses of MH group had higher marbling score and quality grade than those of RS and TH group (P < 0.05). Therefore, higher fat content (P < 0.001), lower shear force and hardness value in the beef of MH group than that of other groups were observed. Furthermore, the beef of MH group had higher CIE $a^*$ value (redness) than that of other groups and feeding MH to Hanwoo steers lowered n-6 to n-3 fatty acids ratio in beef. Conclusions: Mixed hay provided benefits on meat quality and could be used for Hanwoo fattening program.

• Radiation Oncology Journal
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• 제10권2호
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• pp.163-169
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• 1992

1980년 1월부터 1991년 6월까지 경희대학교 부속병원 치료방사선과에서 수술후 방사선치료를 받은 뇌의 악성 성상세포종과 교아세포종 환자 53명을 대상으로 후향적 분석을 실시하였다. 48명이 추적 가능하였으며 5년생존율은 악성 성상세포종이 $29.4\%$였고 교아세포종이 $2.8\%$였으며 중앙생존기간은 각각 27개월, 11개월이었다. 조직 분화도, 나이, 수행능력, 방사선량이 통계학적으로 유의하게 의미있는 예후인자로 나타났다. 종양절제 정도, 증상발현 기간, 종양의 위치에따라 생존율의 차이를 보였으나 통계적인 유의성은 없었다.

• 대한수학교육학회지:학교수학
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• 제5권1호
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• pp.1-25
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• 2003

본 연구는 창의성 신장을 위한 새로운 수학 교육 평가 방안의 하나로 학교에서 사용될 수 있는 수행평가 방안에 대해 논의한다. 먼저 수행평가의 의미와 필요성을 살펴보고, 수행평가 유형과 채점방법에 대해 논의한 다음 필수·학습 상황에서의 활용방안을 제시한다. 이어서, 초등학교와 중학교에서 활용될 수 있는 수행평가의 종류별 예시 문항과 채점 기준을 소개하며. 각 문항에 대한 성취도 평가 결과를 제시한다. 각 과제에는 내용영역, 평가목표, 평가절차, 준비물, 문항의 특징, 평가상 유의점, 체점 기준표 등을 제시하여 수학교육 현장에서 직접 사용하거나 응용할 수 있도록 한다.

• 한국생산제조학회지
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• 제24권5호
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• pp.576-582
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• 2015

Generally, the fuel economy of hybrid electric vehicle (HEV) is effected by the size of each component. In this study the fuel economy for HEV of our own making is evaluated using backward simulator, where dynamic programming is applied. In a competition, the vehicle is running through the road course that includes many speed bumps and steep grade. Therefore, the new driving cycle including road grade is developed for the simulation. The backward simulator is also developed through modeling each component. A performance map of engine and motor for component sizing is made from the existing engine map and motor map adapted to the HEV of our own making. For optimal component sizing, the feasible region is defined by restricting the power range of power sources. Optimal component size for best fuel economy is obtained within the feasible region through the backward simulation.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.759-764
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• 2001

The separation performance of zigzag air classifier with angle of 90 degrees was studied using narrow size fractions of thin square samples and granular samples. The simulation results of air velocity inside the classifier indicated that the zigzag geometry induces a new pattern consisting of an upward flow and a circulation flow, Experimental results showed that overflow product recovery was described as an integral calculus of normal distribution as a function of dimensionless air velocity ( $V_{A}$ $V_{A50}$), where $V_{A}$ is superficial air velocity and $V_{A50}$ is the $V_{A}$ at the fifty percent recovery. The $V_{A}$ values were predicted using the equations derived from dynamics for a particle dropping in air. A monitoring system that utilizes changes in acoustic signals emitted during the process of air classification was developed to separate PET with desired recovery or grade. The technical feasibility of the on-line monitoring of the PET recovery and grade was demonstrated by measuring relative energy of the signals.signals.als.

• Asian Pacific Journal of Cancer Prevention
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• 제16권13호
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• pp.5319-5323
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• 2015

Background: The purpose of this study was to evaluate the prognostic significance of Ki-67 and subjective microvascular density (SMVD) indexes together with other factors in patients with oligodendroglioma. Materials and Methods: In this retrospective study, oligodendroglioma specimens obtained from twenty-five consecutive patients were evaluated for Ki-67 and SMVD indices to help determine histological grading and investigate the fidelity of these markers in clinical prognosis. Other potentially prognostic factors were Karnofsky performance scale, tumor histological grade, and adjuvant radiotherapy. Results: The Ki-67 proliferation index appeared to have a strong correlation with the grade of the tumor and the survival. Age, gender, adjuvant radiotherapy, surgical resection type (complete versus incomplete) did not have any influence on recurrence. The SMVD index correlated significantly with the 3 to 5-year survival. Conclusions: Ki-67 and MVD indexes are important and useful markers in estimating the prognosis of oligodendrogliomas.

• 한국산학기술학회논문지
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• 제11권11호
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• pp.4220-4227
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• 2010

최근 입학사정관제에 대한 여러 가지 논의가 대두되고 있으나, 입학사정관제로 뽑힌 학생들의 대학 입학 후 학업성과에 대한 연구는 거의 이루어지지 않고 있다. 본 논문은 이 주제에 대해 서울 시내 한 대학의 협조로 그 대학의 2009년 입학생 데이터를 이용해 입학사정관 입학생과 일반전형 입학생 간의 입학당시 성적과 입학후 1년간의 학업성과에 대해 분석하였다. 해당 데이터를 분석한 결과 두 가지 주안점이 밝혀졌다. 입학당시 입학사정관 전형 입학생은 일반전형 입학생에 비해 뚜렷하게 떨어지는 학업성과를 보였다. 그러나 입학후 1년간의 평균학점 분석에서 두 전형 입학생 사이에 통계적으로 유의한 학점 차이는 나타나지 않았다. 이 결과는 입학사정관제가 잠재력 있는 학생을 선발하는 효과적인 방법 중 하나라는 사실을 보여준다.