• Journal of the korean Society of Automotive Engineers
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• v.2 no.2
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• pp.1-15
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• 1980

에너지사정은 날이 갈수록 악화일로에 있으며, 이 추세는 장차 그 도를 심화시켜 갈 것으로 전 망된다. 이와 같은 상황하에서 거의 석유베이스의 연료에 의존하고 있는 내연기관 특히 자동차는 경제활동 및 국민생활에 불가결의 수단으로 제공되고 있는 바, 그 수요에 약간의 제동이 걸렸 다고 하지만, 장기적으로 볼 때, 수요증대와 이에 따른 공급증대는 필연적인 것으로 인정되고 있다. 내연기관의 연료로서 석유베이스가 아닌 신대체연료로서 가장 유망시되고 있는 것은 메타 놀과 수소로 보고 있다. 메타놀은 현재 알려진 제조법으로서는, 석탄이나 석유와 같이 매장량이 제한되어 있는 화석의 일차제품에 좌우된다는 문제를 내포하고 있는데 반하여, 수소는 물 및 핵에너지로부터 얻어지므로, 장기적으로 볼 때 가솔린의 일반적인 대용으로서 탄소를 함유하는 원재료에 의존하지 않는 대상이 되는 것은 수수뿐이다. 수소의 이용에 있어서, 제조소로부터 스탠드까지의 하부조직이 없는 것이, 자동차 내 저장문제와 더불어, 오늘날 수소자동차의 일반적 이용을 지지하고 있다고 하더라도, 수소동력은 그 배출가스가 거의 무해한 까닭으로, 가까운 장래에 시내교통과 같은 특수한 경우에는 활용할 수 있을 것이다. 또한 가솔린과 수소의 혼합 연료에 의한 운전을 서서히 도입함으로써, 수소기술로의 전환이 용이하게 된다. 이렇듯 탄소를 함유하는 원료에 의존하지 않는 대체연료로서 수소가 유망시되고 있는데, 이 때 신연료의 이용 가능성만이 중요한 것이 아니고, 연료의 제조, 저장과 분배, 수송, 그리고 자동차의 운전에 이 르기까지의 문제를 기술적 및 경제적 관점에서 파악하여야 한다. 그 가운데서, 특히 신연료가 자동차기관을 중심으로 한 내연기관의 대체연료로서 적합하냐 아니냐, 또한 기관, 연료계통 등에 별로 개조를 가할 필요가 있느냐 없느냐 하는 기술적 파악이 먼저 제기된다. 앞으로 이 문제에 한하여 논의하기로 한다.

• Korean Journal of Poultry Science
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• v.48 no.4
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• pp.207-216
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• 2021

This study was conducted to determine the nutritional quality of two newly-developed native chicken strains, compared to the commercial Korean native chicken. A total of 600 chickens (CON: Hanhyup No. 3, CL1: candidate line C, CL2: candidate line D) raised under the same conditions were slaughtered at either 5 or 12 weeks. Leg meat was then obtained and analyzed for its physicochemical properties. The results showed that regardless of the growing period, there was no variation in proximate composition (P>0.05), except for crude protein, between strains. Water holding capacity did not differ between strains at either slaughter age; however, it was significantly lower in the 12-week group than in the 5-week group (P≤0.05). For both skin and muscle color, a^* and b^* values were lower at 12 weeks than at 5 weeks (P≤0.05). DPPH radical-scavenging activity tended to be lower at 12 weeks than at 5 weeks (P≤0.05). Furthermore, all chickens slaughtered at 5 weeks were found to have greater contents of linoleic acid (18:2) and polyunsaturated fatty acids (PUFA) and lower atherogenicity and thrombogenicity indices than those slaughtered at 12 weeks (P≤0.05). However, anserine, betaine, and glucose were more concentrated among the lines at 12 weeks than at 5 weeks (P≤0.05). In conclusion, the quality traits of native chickens were distinct by different production stages rather than chicken lines.

• Korean Journal of Agricultural Science
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• v.2 no.2
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• pp.341-356
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• 1975

This study was carried out to evaluate three winter active synthetic varieties in a succeeding generations of improvement and polycross progenies of seven genotypes selected at the cool and wet climate of the Western Oregon, in their performance of the polycross progeny test comparing with a control variety, high yielding 'Fawn', at Daejon, Korea. Various plant and leaf characteristics, especially related to photosynthesis, and forage production during the first summer after the establishment were examined. The important conclusions of this study are summarized as follows: 1. The differences of leaf fresh weight among groups and control exhibit genetic differences. The a verage of leaf fresh weight of polycross progeny group was the heaviest and those of winter active synthetic varieties in the succeeding generations of improvement was heavier than variety 'fawn'. Within polycross progeny group the genotypes exhibit genetic differences for leaf dry weight. 2. The leaf area exhibited genetic differences among groups and control. The average of winter active synthetic varieties in a succeeding generation was larger than variety 'Fawn'. Those oi the polycross progeny group was the largest among groups and control. 3. Differences of specific leaf weight(S. L. W.) among and within varieties, genotypes and control were not significant. Further investigation in this respect is necessary through the study of the diurnal change in S. L. W. 4. Differences of leaf width among groups and control exhibited genetic differences. The average leaf width of winter active varieties was larger than those of 'Fawn' variety. And those of polycross progenies of genotypes was the largest. 5. Plant height of 'fawn' variety in the first measurement was higher than those of winter active tall fescue varieties and genotypes. The deviation in plant height among polyeross progenies of seven genotypes gave a great deviation. The regrowth ability of plant height was not different suggesting that this characteristics was about the same among and within groups and control. 6. Plant width, spreading ability, improved through the succeeding generations of the improvement of the winter active synthetic varieties for the first measurement. Differences of plant width at the second measurement among genotypes within polycross progeny group were big enough to show the genetic difference. 7. Tiller number of the winter active synthetic varieties and the average of genotypes in polycross progeny was more than those of the control 'Fawn' in the first measurement. On the second measurement, the differences of tiller number appeared among three synthetic varieties indicating improvement, and there were genetic differences among seven genotypes in polycross progeny test. 8. Forage yield on the first cutting showed a considerble improvement of forage yield in the more advanced generation of synthetic varieties and genetic differences among seven genotypes in the polycross progeny test. The average of polycross progeny group was higher than those of the control or three winter active varieties. It was suggested that we could make a further improvement for the forage yield. 9. The regrowth ability of these winter active varieties and genotypes was about the same capacity at least on the measurement of the regrowth in forage yield and plant height during summer. 10. On the whole, the averages of the polycross progeny group was in the highest value and those of synthetic varieties were higher than the control variety, 'Fawn', for the most characteristics except S. L. W. and the plant height on the first measurement even though the differences were not always significant. And there were genetic differences among seven gentypes in their performance of the polycross progeny. 11. Although it was not always sgnificant, the most advanced winter active variety, '1002', had in the highest value for all plant characteristics and forage yield measurements than the other two varieties, '1001'. 12. The results of the association study among various characteristics were quite agreeable and would be useful in the selection of desirable genotypes for the development of a better variety.

• Nuclear Engineering and Technology
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• v.26 no.1
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• pp.126-139
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• 1994

Best-estimate thermal-hydraulic codes, CATHARE2 V1.2 and RELAP5/MOD3, hate been assessed against the BETHSY 6.2 tc six-inch cold leg break loss-of-coolant accident (LOCA) test. Main objective is to analyze the overall capabilities of the two codes on physical phenomena of concern during the small break LOCA i.e. two-phase critical flow, depressurization, core water level de-pression, loop seal clearing, liquid holdup, etc. The calculation results show that the too codes predict well both in the occurrences and trends of major two-phase flow phenomena observed. Especially, the CATHARE2 calculations show better agreements with the experimental data. However, the two codes, in common, show some deviations in the predictions of loop seal clearing, collapsed core water level after the loop seal clearing, and accumulator injection behaviors. The discrepancies found from the comprision with the experimental data are larger in the RELAP5 results than in the CATHARE2. To analyze the deviations of the two code predictions in detail, several sensitivity calculations have been performed. In addition to the change of two-phase discharge coefficients for the break junction, fine nodalization and some corrections of the interphase drag term are made. For CATHARE2, the change of interphase drag force improves the mass distribution in the primary side. And the prediction of SG pressure is improved by the modification of boundary conditions. For RELAP5, any single input change doesn't improve the whole result and it is found that the interphase drag model has still large uncertainties.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.3
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• pp.331-337
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• 2018

The decommissioning of nuclear power plants is generally executed in five steps, including preparation, decontamination, cutting/demolition, waste disposal and environmental restoration. So, for efficient decommissioning of nuclear power plants, worker safety, effects compared to cost, minimization of waste, possibility of reuse, etc., shall be considered. Worker safety and measurement technology shall be secured to exert optimal efficiency of nuclear power plant decommissioning work, for which accurate measurement technology for systems and devices is necessary. Typical In-Situ methods for decommissioning of nuclear plants are CZT, Gamma Camera and ISOCS. This study used ISOCS, which can be applied during the decommissioning of a nuclear power plant site without collecting representative samples, to take measurements of the S/G Water Chamber. To validate the measurement values, Microshield and the GEANT4 code was used as the actual method were used for modeling, respectively. The comparison showed a difference of $1.0{\times}10^1Bq$, which indicates that it will be possible to reduce errors due to the influence of radiation in the natural environment and the precision of modeling. Based on the research results of this paper, accuracy and reliability of measurement values will be analyzed and the applicability of the direct measurement method during the decommissioning of NPPs will be assessed.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.13 no.3
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• pp.295-304
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• 2000

To evaluate the structural integrity for the strainer under seismic loading the seismic analysis and design were performed for T-type strainer in accordance with ASME, Section Ⅲ, Class 3(ND). Since there are no specified design requirements for the strainer in ASME Code, the strainer body was analysed according to ND-3500, valve design. Flanged joints connected with PCS piping were designed according to ND-3658.3. And the criteria for the cover flange was governed by the Appendix XI. Both a frequency analysis and an equivalent static seismic analysis of the strainer were carried out using the finite element computer program, ANSYS. The frequency analysis results show the fundamental natural frequency is greater than 33Hz, thus justifying the use of the equivalent static analysis through which membrane and bending stresses are obtained in the critical points near the branch connection area. The results of the seismic evaluation fully satisfied with the structural acceptance criteria of the ASME Code. Accordingly the structural integrity on the strainer body and flanges were proved.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.33 no.2
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• pp.123-129
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• 2015

The Kalman filter has been widely used in the kinematic GPS positioning due to its flexibility and efficiency in computational points of view. At the same time, the relative positioning technique also provided the high precision positioning results by removing the systematic errors in the measurements significantly. However, the positioning quality may be degraded following to longer in baseline length. For this case, it is required that the remaining atmospheric effects, such as double-difference ionospheric delay and zenith wet delay, should be properly modeled by examining the characteristics of the stochastic processes. In general, atmospheric effects are estimated with the assumption of random walk, or the first-order Gauss-Markov stochastic process, which requires the precise modeling on the corresponding process noises. Therefore, we determined and provided the parameters for modelling the process noises for atmospheric effects. The auto-correlation functions are empirically determined at first, and then the parameters are extracted from the empirical auto-correlation function. In fact, the test results can be either applied directly, or used as guidance values for the modeling of process noises in the kinematic GPS positioning.

• The Journal of Pediatrics of Korean Medicine
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• v.18 no.2
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• pp.49-59
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• 2004

Objective : The purpose of this study is to demonstrate the therapeutic effect of oriental treatment on Acute Myelogenous Leukemia. Methods : The patient was treated by Acupuncture, Indirect Moxibustion, Herb Medicine (Seogakjihwangtang-gamibang), and had significant improvement in the Acute Myelogenous Leukemia. Results : 1. Acute Leukemia is one of the most common malignant neoplasm of pediatrics, and is chracterised by anemia, infections, bleeding, debility, paleness, fever, anorexia, lymphoadenia, hepatomegaly, splenomegaly, etc. 2. The management of Acute Myelogenous Leukemia consists of the challenge of optimizing chance for prolonged remission and cure, while minimizing the toxicity to the patients. Therefore oriental medical treatment may be useful for this. 3. We experienced a case of the 10-year-old male patient with Acute Myelogenous Leukemia, after oriental medical treatment his chief symptoms(anemia, bleeding, purpura, debility, paleness, fever, anorexia, insomnia, etc)and general condition were improved. Conclusion : A 10-year-old male patient with Acute Myelogenous Leukemia, after oriental medical treatment his chief symptoms and general condition were improved. This oriental medical treatment may be possible or effective in Acute Myelogenous Leukemia. The more clinical study about oriental medical treatment on Acute Myelogenous Leukemia will be needed.

• Current Research on Agriculture and Life Sciences
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• v.9
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• pp.1-9
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• 1991

Bulbs of two introduced garlic cultivars, Sanghae-joseng and Spain strain, were purchased in a market and anatomical characteristics of them were investigated according to the weight of individual bulbs. The materials used were planted and grown in the field. Bulbs harvested were classified according to weight and their anatomical characteristics were recorded. 1. In both cultivars the larger the bulb, the more flat the bulb shape. 2. The bigger the bulbs were, the larger the number of cloves per bulb was, Spain strain had more cloves per bulb than Sanghae-joseng in the same size bulbs. 3. In Sanghae-joseng, more cloves were formed in outer layer than in inner layer in the bulbs produced in 1990. But more cloves were formed in inner layer in the bulbs of 35 g or smaller produced in 1991. In Spain strain, more cloves were formed in inner layer in the bulbs of 40 g or more produced in 1990. But more cloves were formed in outer layer in the bulbs produced in 1991 regardless of bulb size. In both cultivars, the number of primary cloves and total number of cloves was very small in both cultivars, but it was a little bigger in Sanghae-joseng than in spain strain. 5. In the bulbs produced in both 1990 and 1991 of Spain strain and in bulbs produced in 1990 of Sanghae-joseng weight of cloves in outer layer was significantly heavier than that in outer layer, the trend was not conspicuous in 1991 produce of Sanghae-joseng. 6. In both cultivars clove size range was narrow in small bulbs and wide in large bulbs. In distribution of cloves in size, medium ones were most frequent, and the frequency of large cloves increased with increased size of bulbs. Sanghae-joseng produced larger cloves than Spain strain in the same size cloves.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.20 no.3
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• pp.141-150
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• 2015

Dinoflagellates are ubiquitous and important primary producers in the oceans. They have diverse trophic modes, i.e., phototrophic, heterotrophic, and mixotrophic modes and thereby, play important ecological role in marine microbial food-web. While many studies have been focused on planktonic dinoflagellates in pelagic ecosystems, benthic, sand-dwelling dinoflagellates that inhabit in intertidal zone have been very poorly documented worldwide. We investigated biodiversity, occurrence, and molecular phylogeny of benthic, sand-dwelling dinoflagellates from the intertidal flat of Dongho, west coast of Korea during low-tide, monthly from November 2012 to February 2014. About 27 species of 13 genera in orders Gonyaulacales, Gymnodiniales, Peridiniales, Prorocentrales have been identified, of which members in the genus Amphidinium constituted a major part of the sand-dwelling dinoflagellates in this area. A total of 34 isolates from 16 species of the sand-dwelling dinoflagellates were isolated from Dongho, Mohang, Gamami, and Songho in the west coast and Hyupjae in Jeju of Korea, their 28S rDNA sequences were successfully amplified, and applied for molecular phylogenetic analyses. In the 28S rDNA phylogeny, Amphidinium species diverged across three major clusters within the order Gymnodiniales and formed polyphyletic group. Based on the unambiguously aligned partial 28S rDNA sequences including variable D2 region, the genotypes of Amphidinium mootonorum Korean strains greatly differed from that of Canadian strain with 19.2% of pairwise nucleotide difference, suggesting that further ultrastructural studies may provide additional characters to clearly separate these genotypes. Two potential toxic species, Amphidinium carterae and A. operculatum appeared occasionally during this study. Quantitative assessment and toxicity of those species should be addressed in the future.