• Nuclear Engineering and Technology
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• 제55권11호
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• pp.4274-4281
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• 2023

Blanket is of vital importance for engineering application of the fusion reactor. Nuclear heat deposition in materials is the main heat source in blanket structure. In this paper, the three-dimensional method for thermal-hydraulics/neutronics coupling analysis is developed and applied for the full-scale module of the helium-cooled ceramic breeder tritium breeding blanket (HCCB TBB) designed for China Fusion Engineering Test Reactor (CFETR). The explicit coupling scheme is used to support data transfer for coupling analysis based on cell-to-cell mapping method. The coupling algorithm is realized by the user-defined function compiled in Fluent. The three-dimensional model is established, and then the coupling analysis is performed using the paralleled Coupling Analysis of Thermal-hydraulics and Neutronics Interface Code (CATNIC). The results reveal the relatively small influence of the coupling analysis compared to the traditional method using the radial fitting function of internal heat source. However, the coupling analysis method is quite important considering the nonuniform distribution of the neutron wall loading (NWL) along the poloidal direction. Finally, the structure optimization of the blanket is carried out using the coupling method to satisfy the thermal requirement of all materials. The nonlinear effect between thermal-hydraulics and neutronics is found during the blanket structure optimization, and the tritium production performance is slightly reduced after optimization. Such an adverse effect should be thoroughly evaluated in the future work.

• Journal of the Korean Wood Science and Technology
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• 제39권2호
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• pp.163-171
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• 2011

Because Japanese cedar shows lower mechanical performance, glued-laminated timber (glulam) can be a better way to utilize Japanese cedar for structural purpose. However, low yield of higher grade lamination from log makes it difficult to design structural glulam. This study was aimed to increase the yield of higher grade lamination and provide higher efficiency of manufacturing structural lamination by ultrasonic log sorting technology. Logs were sorted by an existing log grading rule regulated by Korea Forest Research Institute (KFRI). It was found that the KFRI log grading rule contributed to finding better logs in viewpoint of the volumetric yield and it can reduce the number of rejected lumber by visual grading. However, it could not identify better logs to produce higher-grade products. To find an appropriate log-sorting-method for structural products, log diameter and ultrasonic time of flight (TOF) for the log were considered as factors to affect mechanical performance of resulting products. However, it was found that influence of log diameter on mechanical performance of resulting products was very small. The TOF showed a possibility to sort logs by mechanical performance of resulting products even though a coefficient of correlation was not strong (R = 0.6). In a case study, the log selection based on the ultrasonic TOF of the log increased the yield of the outermost tension lamination (E8 or better grade, KS F 3021) from 2.6% to 12.5% and reduced LTE5 (lower than E5 grade) lamination from 43.6% to 10.3%, compared with the existing KFRI log grading rule.

• Journal of Animal Science and Technology
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• 제51권1호
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• pp.69-74
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• 2009

본 연구는 도체 등급판정을 받은 비육돈 LY 및 LYD 교잡종 중 암퇘지 128두와 거세돈 528두, 총 656 두를 공시돈으로 교배조합, 도체등급 및 출하일령별 도체 및 육질특성을 조사하여 고급돈육생산에 필요한 기초적 자료를 얻고자 실시하였다. 교배조합별 도체특성의 변화에서 근내 지방도와 보수력은 두 교배조합 간에 각각 통계적으로 유의한 차이(p<0.05)를 보였으나, 도체중, 등지방 두께, 육색, 도체등급 및 출하일령은 두 교배조합 간에 유의차가 나타나지 않았다. 도체등급별 도체특성 분석에서 도체중은 도체등급이 떨어질수록 유의하게(p<0.05) 무거웠다. 등지방 두께는 도체등급이 높을수록 유의하게(p<0.05) 얇은 성적을 나타났으나, 육색도에서는 도체등급간에 통계적 유의차는 없었다. 보수력은 도체등급 간에 유의한 차이(p<0.05)를 보인 반면에, 출하일령은 유의성 있는 차이는 나타나지 않았다. 출하일령별 도체특성에서 도체중과 등지방 두께는 출하일령 간에 통계적으로 유의하게(p<0.05) 일령이 많을수록 무겁게 나타났으나, 육색은 일령간에 유의한 차이를 보이지 않았다. 근내 지방도는 출하일령이 많을수록 유의하게(p<0.05) 높았으나, 도체등급과 보수력에서는 출하일령이 적을수록 유의하게(p<0.05) 높게 나타났다. 그리고 A 등급 출현율은 출하일령이 높은 돈군보다 166~170 일령 돈군에서 53.5%로 가장 높게 나타났다. 도체형질 간의 상관계수 추정에서 도체중은 등지방 두께와 정(+)의 중등 상관이었으나, 도체등급과는 부(-)의 상관이 존재하였으며, 등지방 두께와 도체등급 간에는 부(-) 상관, 육색과 보수력 간에는 고도의 부(-)의 상관, 그리고 근내 지방도와 보수력은 정(+)의 중등 상관이 각각 존재하였다.

• 한국환경복원기술학회지
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• 제11권1호
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• pp.1-13
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• 2008

This study review of Compositional Evaluation Items for Environmental Conservation Value Assessment Map (ECVAM) in Korea. The ECVAM is composed of legal assessment and environmental/ecological assessment items. ECVAM basically adapts an overlay method for environmental/ecological assessment items. The objective of this study is to suggest supplementary items for the ECVAM with the following process : Overlapping rates of the assessment items in the ECVAM are calculated to understand the grade distribution of the environmental conservation value assessment and to analyze the overlapping rates among the assessment items, as a result it is found that various items are overlapped each other. In order to reflect effectively each assessment item to the ECVAM, Analyzed the overlapping degree among assessment items to be applied to this map. On the concrete we gripped results to be assessed by various items, which were overlapped each other. In order to reflect effectively each assessment item to the environmental conservation value assessment map of national land, we analyzed the overlapping degree on environmental/ecological items, and investigated the grade distribution by field survey. In this study we assessed the ECVAM by 5 kinds of method. Method 1 is Grade 1 areas of each administrative district, Method 2 is Comparing overlapping areas of each assessment items Grade 1, 2 and Permission of each assessment items' duplication, Method 3 is Grade 1, 2 areas by only singular assessment items, Method 4 is Only Grade 1 areas of Method 2 and Method 5 is Only Grade 2 areas of Method 2. As results, Method 1 showed Seoul and other metropolitan cities reveal a high proportion of Grade I regions by the legal assessment items. Kangwon-Do, show a high proportion of Grade I regions by the environmental/ecological assessment item. Method 2 showed 93.4% of diameter Grade II(standard for stability), forest diameter item was accounted for 99.9% by Method 3, Method 4 showed 95.7% of forest diameter and forest density was accounted for 66.4% by Method 5. From now on, this study will contribute to reduce the complexity in the process of manufacturing ECVAM of National Land, and to raise the pliability in the process of managing and updating this map.

• Journal of Microbiology and Biotechnology
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• 제31권4호
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• pp.550-558
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• 2021

Lactobacillus kefiranofaciens contains two types of β-galactosidase, LacLM and LacZ, belonging to different glycoside hydrolase families. The difference in function between them has been unclear so far for practical application. In this study, LacLM and LacZ from L. kefiranofaciens ATCC51647 were cloned into constitutive lactobacillal expression vector pMG36e, respectively. Furtherly, pMG36n-lacs was constructed from pMG36e-lacs by replacing erythromycin with nisin as selective marker for food-grade expressing systems in Lactobacillus plantarum WCFS1, designated recombinant LacLM and LacZ respectively. The results from hydrolysis of o-nitrophenyl-β-galactopyranoside (ONPG) showed that the β-galactosidases activity of the recombinant LacLM and LacZ was 1460% and 670% higher than that of the original L. kefiranofaciens. Moreover, the lactose hydrolytic activity of recombinant LacLM was higher than that of LacZ in milk. Nevertheless, compare to LacZ, in 25% lactose solution the galacto-oligosaccharides (GOS) production of recombinant LacLM was lower. Therefore, two β-galactopyranosides could play different roles in carbohydrate metabolism of L. kefiranofaciens. In addition, the maximal growth rate of two recombinant strains were evaluated with different temperature level and nisin concentration in fermentation assay for practical purpose. The results displayed that 37℃ and 20-40 U/ml nisin were the optimal fermentation conditions for the growth of recombinant β-galactosidase strains. Altogether the food-grade Expression system of recombinant β-galactosidase was feasible for applications in the food and dairy industry.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1995년도 춘계학술대회 논문집
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• pp.174-180
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• 1995

• Educational Technology International
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• 제9권1호
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• pp.25-47
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• 2008

The purpose of this study is to investigate online school students' understanding of going to online school and their recognitions of the differences between online schools and brick and mortar schools/homeschool. A qualitative research was conducted with an 8^th grade teacher and sixteen 8^th grade students at an American online school. The findings of this study can be an important first step toward an in-depth understanding of online school learning environments.

• 산업기술연구
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• 제9권
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• pp.29-41
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• 1989

A general study on the upgrading of mica minerals which are mainly found in pegmatite deposits was carried out for the purpose of developing a technique for recovering mica in form of comercial grade products. By the way the grade one of about 5~6% $K_2O$ still is not developed. The target of this research work is to be establish a process for the efficient concentration of muscovite, containing more than 10% $K_2O$. The tests are applied to incraese the recovery and grade of concentrates in term of variations of conditions. The test sample consists of mainly muscovite and gangue mineral such as quartz, pyrite and chlorite. Decantation and shaking table tests were ineffective to up-grade this low grade one, but flotation method gave satisfactory result. By means of grade one, but flotation method gave satisfactory result. By means of grindability tests, an optimum result could be obtained from the sample ground to -48mesh feed size. The flotation result indicates that the dodecyl ammonium chloride used as a cationic collector is effective on the negatively charged surface, while the sodium dodecyl sulfate as an anionic collector is effective on the positively charged surface. Muscovite was floated by petroleum sulfonate as well as amine type collector, it also floated by MIBC as well as pine oil frother under well condition. Fine muscovite concentrates of about 10.68% $K_2O$ was obtained with 22.4% yield, by decantation, the muscovite concentrates of 10.10% $K_2O$ was obtained with 23.54% yield, by table concentration, the muscovite concentrates of 11.51% $K_2O$ was obtained with 23.0% yield by flotation.

• Journal of Animal Science and Technology
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• 제63권5호
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• pp.1086-1097
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• 2021

This study examined the impact of using total mixed ration (TMR) and concentrate on feed intake, daily gain, carcass yield grade, and carcass quality grade of Hanwoo steers and its subsequent economic efficiency. Thirty six 7-month-old Hanwoo steers were assigned to one of the four treatment groups, and each group was divided into three repeated pens, with each repeated pen comprising three steers. The treatment groups were: 1) separate feeding with commercial concentrate and forage (namely, SCF) for the entire experimental period; 2) TMR feeding for a growing period followed by SCF for the early and late fattening period (namely, TMRGSCF); 3) TMR feeding for growing and an early fattening period followed by SCF for the late fattening period (namely, TMREFSCF); and 4) TMR feeding for the entire experimental period (namely, TMRW). The results showed that the SCF treatment had significantly (p < 0.05) higher feed intake during the growing period than other treatments. In contrast, the total feed intake had little difference during early and late fattening as well as the whole period regardless of feeding strategies. Daily gain showed no difference during the growing period. However, it was significantly higher in SCF and TMREFSCF treatments for the early and late fattening period, respectively (p < 0.05). The daily gain during the total raising period is in the order of TMREFSCF > TMRGSCF > SCF > TMRW. Carcass characteristics, including carcass weight, loin eye muscle area, and carcass yield grade, did not significantly differ among different treatments. However, TMRW treatment, wherein TMR was fed for a long time, showed that the cold carcass weight was less compared with other treatments, but carcass yield grade was higher with thinner backfat. Backfat thickness was in the order of SCF > TMRGSCF > TMREFSCF > TMRW, showing that the thickness reduced with longer TMR feeding (p < 0.05). TMRGSCF, which numerically had a higher carcass quality grade, showed higher economic efficiency, whereas SCF showed low economic efficiency. In conclusion, it was more feasible to apply TMR strategy in the growing and early fattening period and then SCF for the early or late fattening period to improve carcass yield, quality grade, and economic efficiency.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 2001년도 The Pacific Aisan Confrence On Intelligent Systems 2001
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• pp.237-245
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• 2001

Automated essay grading has been proposed for over thirty years. Only recently have practical implementations been constructed and tested. This paper investigated the role of the nearest-neighbour algorithm within the information retrieval as a way of grading the essay automatically called Automated Essay Grading System. It intended to offer teachers an individualized assistance in grading the student\`s essay. The system involved several processes, which are the indexing, the structuring of the model answer and the grade processing. The indexing process comprised the document indexing and query processing which are mainly used for representing the documents and the query. Structuring the model answer is actually preparing the marking scheme and the grade processing is the process of assessing the essay. To test the effectiveness of the developed algorithms, the algorithms are tested against the History text in Malay. The result showed that th information retrieval and the nearest-neighbour algorithm are practical combination that offer acceptable performance for grading the essay.