• Nuclear Engineering and Technology
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• 제55권9호
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• pp.3464-3471
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• 2023

The Uranium/Molybdenum metallic fuel has been proposed as promising advanced fuel concept especially in the dispersed fuel geometry. The fuel is manufactured in the form of small fuel droplets (particles) placed in a fuel pin covered by a matrix. In addition to fuel particles, the pin contains voids necessary to compensate material swelling and release of fission gases from the fuel particles. When investigating this advanced fuel design, two important questions were raised. Can the dispersed fuel performance be analyzed using homogenization without significant inaccuracy and what size of fuel drops should be used for the fuel design to achieve optimal utilization? To answer, 2D burnup calculations of fuel assemblies with different fuel particle sizes were performed. The analysis was supported by an additional 3D fuel pin calculation with the dispersed fuel particle size variations. The results show a significant difference in the multiplication factor between the homogenized calculation and the detailed calculation with precise fuel particle geometry. The recommended fuel particle size depends on the final burnup to be achieved. As shown in the results, for lower burnup levels, larger fuel drops offer better multiplication factor. However, when higher burnup levels are required, then smaller fuel drops perform better.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2005년도 추계학술발표논문집
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• pp.259-263
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• 2005

This study was performed to introduce recently developed Polyvinylamine as a wet-end process improving aids and paper properties improving aids. As a retention and drainage aids, cationicity of Polyvinylamine was a very important factor of BCTMP and ONP stock condition. As a dry tensile strength aids, The hydrogen bond of acrylamide functionality and hydroxyl functionality of the pulp was a very important factor of LBKP stock condition and cationicity of Polyvinylamine was a very important factor of BCTMP and ONP stock condition.

• 전기학회논문지P
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• 제63권4호
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• pp.248-253
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• 2014

Generally, power factor correction (PFC) techniques play an important role in the power supply technology. Many new circuit topologies and control strategies for PFC have been proposed. Among them, the brideless PFC (BPFC) reduces the number of switching devices and the losses and improves the power density as well. Moreover, by implementing the improved topology in the discontinous conduction mode (DCM) it ensures almost unity power factor in a simple and effective manner. In the DCM operation gives additional advantages such as zero-current turn-on in the power switches, zero-current turn-off in the output diode and reduces the complexity of the control circuitry. In this paper, a new control strategy for the BPFC is proposed. Also, the performance of the proposed system is demonstrated through experiments.

• Journal of Dental Anesthesia and Pain Medicine
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• 제19권3호
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• pp.125-134
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• 2019

Successful local anesthesia in dental treatment is the most important prerequisite for pain control of patients. However, unlike that in the maxilla, it is difficult to administer local anesthesia in the mandible, and the success rate of conventional inferior alveolar nerve block (IANB) is only 80-85%. It is attributed to various causes such as anatomical variations, extreme anxiety, and technical errors; thus, various alternatives have been devised to improve this. We will analyze the causes of failure in conventional IANB and examine various alternatives that can be applied in these cases.

• 가정과삶의질연구
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• 제28권6호
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• pp.95-111
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• 2010

The purposes of this study were to show general trends in the aspects of psychological family environment (parental communication), peer factor, academic performance factor, depression perceived by adolescents and to examine possible changes in such trends in accordance with demographic variables and the family structure environment (parental marital status, family economic status, and parents' education level), and then to determine the effect of these variables on adolescents' depression. The subjects were 1009 middle and high school students in Seoul and Gyeonggi province. The main results were as follows: 1) Paternal communication was significantly lower in technical high school students, divorced/ separated parents, and families of lower economic status. Maternal communication was significantly lower in male students, divorced/sepa-rated parents, and families of lower economic status. Academic performance problems was significantly higher in males, technical high school students, divorced/ separated parents, families of lower economic status, and a less educated father. Peer relations was significantly lower in students of divorced / separated parents, and of families of lower economic status. Depression was significantly higher in technical high school students, divorced / separated parents, and families of lower economic status. 2) In the case of male students, paternal communication had both a direct and an indirect negative effect through peer relations on depression, while academic performance problems had both a direct and an indirect positive effect through peer relations on depression. Both peer relations and maternal communication had a positive and a negative direct effect on depression. School grade had both a direct and an indirect negative effect through paternal communication on depression. Parental marital status(divorced or separated) had both a direct and an indirect positive effect through academic performance problems on depression. Family economic status had only an indirect effect on discussed.

• Journal of Microbiology and Biotechnology
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• 제11권3호
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• pp.497-503
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• 2001

The purpose of this study was to examine the efficacy and mechanism of the cryo-precipitation, solvent/detergent (S/D) treatment, monoclonal anti-FVIIIc antibody (mAb) column chromatography, Q-Sepharose column chromatography, and lyophilization involved in the manufacture of antithemophilic factor VII(GreenMono) from human plasma, in the removal and/or inactivation of blood-borne viruses. A variety of experimental model viruses for human pathogenic viruses, including the bovine viral diarrhoea virus (BVDV), bovine herpes virus (BHV), murine encephalomyocarditis virus (EMCV), and porcine parvovirus (PPV), were all selected for this study. BHV and EMCV were effectively partitioned from a factor VII during the cryo-precipitation with a log reduction factor of 2.83 and 3.24, respectively. S/D treatment using the organic solvent, tri(n-butyl) phosphate (TNBP), and the detergent, Triton X-100, was a robust and effective step in inactivating enveloped viruses. The titers of BHV and BVDV were reduced from the initial titer of 8.85 and $7.89{log_10} {TCID_50}$, respectively, reaching undetectable levels within 1 min of the S/D treatment. The mAb chromatography was the most effective step for removing nonenveloped viruses, EMCV and PPV, with the log reduction factors of 4.86 and 3.72, respectively. Q-Sepharose chromatography showed a significant efficacy for partitioning BHV, BVDV, EMCV, and PPV with the log reduction the log reduction factors of 2.32, 2.49, 2.60, and 1.33 respectively. Lyophilization was an effective step in inactivating g nonenveloped viruses rather than enveloped viruses, where the log reduction factors of BHV, BVDV, DMCV, and PPV were 1.41, 1.79, 4.76, and 2.05, respectively. The cumulative log reduction factors of BHV, BVDV, EMCV, and PPV were ${\geqq}$11.12, ${\geqq}$7.88, 15.46, and 7.10, respectively. These results indicate that the production process for GreenMono has a sufficient virus-reducing capacity to achieve a high margin of the virus safety.

• 한국주거학회논문집
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• 제18권6호
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• pp.93-101
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• 2007

This study was to find out users' satisfaction on the dormitory of high school in Jeonju City and to propose it's physical environmental improvement directions. This was performed by a questionnaire survey method, and the questionnaire was designed by researchers considering relative literatures. Data were collected from 200 students, who had been dwelling 4 high school dormitories in Jeonju City. By analyzing those data, findings were as follows: 1) Users of students were satisfied the whole of their dormitory; facilities, spaces, and living. 2) They were highly concerned about a library and a personal unit space in their dormitory. 3) They needed their personal unit space to be designed bedroom+bathroom type with 2 persons' sharing and be equipped one story bed and desk furniture. Also, they needed improvement on heating & cooling, small space and indoor air quality of unit space. 4) The users' satisfaction on unit space were 2.88, and their satisfaction of the technical factor was 2.71 that was the lowest score in them. And The functional factor was highly effected their satisfaction. 5) The space utility and the space size of functional factor, the soundproof, the heating/ventilation and the indoor quality of technical factor, and the privacy of behavior factor were highly correlative to their satisfaction of unit space.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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• pp.313-319
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• 2003

It is well known that ascorbic acid (VC) is an important factor for several physiological reactions. In the skin, VC works as an anti-aging agent due to removing of oxidative stress generated by UV irradiation and stimulation of collagen synthesis. Thus, developing more effective VC derivatives is an important issue in creating anti-aging skin care products. Our study succeeded to develop a novel ascorbic acid derivative, ascorbic acid tetra-2-hexyldecanoate (VC-IP), which is a lipid-soluble pro-VC. The purpose of this study was to indicate the effects of VC-IP as pro-VC and anti-aging agent. First, it was examined whether VC-IP is converted to VC in physiological conditions. Since VC was detected from the cell extracts treated with VC-IP, it was indicated that VC-IP is a pro- VC.(omiited)

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2009년도 춘계학술대회
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• pp.337-350
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• 2009

Using the Malmquist productivity index, this paper compares the productivity of Korean manufacturing industries from 1999 to 2006. The malmquist productivity index has more advantages than previous methods such as solow model, endogenous growth theory. The malmquist productivity index can be decomposed productivity into two parts. The first part is an index of the technical efficiency change. This index has high value when the elements of production is used more efficiently. The second part is an index of technical change. This index has high value if the advent of new technology and process innovation occur.

• 한국건설관리학회논문집
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• 제17권5호
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• pp.3-12
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• 2016

최근 정부는 기술 위주의 경쟁을 강화하는 차원에서 기술제안입찰방식을 점차 확대시켜 나가고 있다. 기술제안입찰방식은 다방면의 복잡한 기술이 적용되고 이러한 기술들을 설계도서에 반영할 시 비용, 공기, 시공성 등의 측면에서 원안에 대한 변수가 발생될 수 있기 때문에, 참여자간의 협업이 중요함에도 불구하고 이에 대한 관리는 미흡하였다. 따라서 본 연구에서는 기술제안입찰에서 참여자간의 협업지원을 위해 협업저해요인을 도출하여 이를 중점적으로 관리하는 방향을 도출하고자 하였다. 이를 위해 첫째로 요인분석을 실시하여 협업저해요인을 5가지 유형으로 분류하였고 두 번째로 분류된 5가지 요인들과 기술제안입찰 각 업무별 참여자간의 상관분석을 통해 변수간의 상관도를 분석하였다. 변수간의 상관도가 높은 협업저해요인을 중점협업관리요소로 정의하고 끝으로 각 업무별로 이를 관리할 수 있는 방향을 제시하였다.