• Journal of Korean Society of Forest Science
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• v.69 no.1
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• pp.1-5
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• 1985

Growth characters such as height, DBH, crown width, branch length and branch diameter were measured from 23 clones of plus trees of Pinus koraiensis. The results were as follows; 1) Differences between the largest and smallest clones were amounted to 41% in height, 81% in DBH, 50% in crown width, 55% in branch length and 83% in branch diameter. 2) There were significant differences between clones in every growth characters and correlation coefficients between growth characters were positive and significant ($r=0.418^*{\sim}0.917^{**}$). 3) The broad sense heritabilities were 0.46 for height, 0.45 for DBH, 0.28 for crown width, 0.26 for branch length and 0.18 for branch diameter. 4) The genetic gains predicted for each characters were ranged from 4.1% to 11.1%, when selecting the best 3 out of 23 clones.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.40 no.4
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• pp.304-310
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• 2004

Resistance performance of small size fishing vessel is experimentally investigated to find out the effect of fore-body shape and trim for the better hull from development. The tests are performed for five different cases in the high speed circulating water channel(CWC). Wave patterns are observed to investigate the relation between the resistance performance and the wave characteristics.

• The Journal of Engineering Geology
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• v.17 no.2 s.52
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• pp.309-315
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• 2007

The purpose of this paper is to make a close inquiry into the relationship between width and length of crack as a method to maximize compensation effect by grouting discontinuity within weak bedrock, together with emphasis on application of the basic data to the reformation of weak bedrock in a construction site. The result reveals that the length of trace at each fracture averages $1.5{\sim}3.0mm$. Based on analysis of openness distribution pattern at each fracture, the estimated values are quite well in agreement with those of the experiment, with a negative trend in the distribution of aperture width.

• Nuclear Engineering and Technology
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• v.22 no.2
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• pp.116-127
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• 1990

The fission gas release model used In the SPEAR-BETA fuel performance code was modified by use of effective thermal conductivity for cracked fuel and by laking Into account axial fission-gas mixing between the fuel-clad gap and the plenum. With use of this modified model the fission gas release was analyzed under various power ramping conditions of P$_{max}$ and $\Delta$.fP. Effective fuel thermal conductivity that accounts for the effect of fuel tracking was used in calculation of the fuel temperature distribution and the Internal gas pressure under power ramping conditions. Mixing and dilution effects due to axial gas flow were also considered in computing the width and the thermal conductivity of the gap. The effect of axial gas flow w3s solved by the Crank-Nicholson method. The finite difference method was used to save running time in the calculation. The present modified fission-gas release model was validated by comparing its predicted results with experimental data from various lamping tests In the literature and calculated results with use of the models used In the SPEAR-BETA and FEMAXI-IV codes. Results obtained with use of the present modified model showed better agreement with experimental data reported in the literature than those results with use of the latter codes. The fuel centerline temperature calculated with introduction of effective thermal conductivity for centerline temperature calculated with Introduction of effective thermal conductivity for cracked fuel was 200 higher fission gas release predicted with use of the modified model was nearly 6% larger on the average than that calculated by use of the unmodified model used in the SPEAR-BETA code.e SPEAR-BETA code.e.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.40 no.1
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• pp.37-46
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• 2004

In order to increase fishing efficiencies of the fyke net used in the coast of Jeju Island, water tank experiment was caried out entering and escaping behavior using nets that were reduced to 1/20 of the size of the full scale fyke net and were improved to have antrance structure, and mackerel Scomber japonicus as experimental fish. The results of measurement are as follows : 1. Fish school behavior in the main net was showed two different patterns : swimming in a circle in the right space of the main net and swimming back and forth in ellipse in the right and left space. 2. The swimming speed of mackerel school was 23.9. 12.6 and 32.0cm/sec in the center space, right space of main net and in the mouth 3. The entering rate of fish school was 40% in net with 35cm length of the upper and funnel net in the mouth of fyke model net and 49% in conventional type fyke model net. 4. The escaping rate of fish school was 10% in net with 35cm length of the upper and funnel net in the mouth of fyke model net and 69% in conventional type fyke model net. 5. The remain rate of fish school was 90% in net with 35cm length of the upper and funnel net in the mouth of fyke model net and 31% in conventional type fyke model net.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.6
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• pp.559-564
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• 2016

We investigated the effect of calcium carbonate on the quality of wine obtained from Gaeryangmerou (Vitis. spp.), grapes, which are commonly used in wine making in Korea. Alcoholic fermentation was carried out at $25^{\circ}C$, for 7 days in the presence of 0.1%, 0.2%, and 0.3% calcium carbonate. As calcium carbonate concentration increased, the pH of wine increased, while its total acid content and redness decreased. Calcium carbonate treatment during precipitation and aging is more effective than during fermentation. Concentrations of alcohol, total anthocyanin, polyphenol, and tannin showed no significant differences between controls and deacidified groups. Tartaric and malic acids were found to be the major acids in Gaeryangmerou wine. Calcium carbonate reduced total acidity by precipitating tartaric acid. In the sensory evaluation of the acidity, and overall acceptability, wine treated with 0.1% calcium carbonate was the best. Higher calcium carbonate concentration, was associated with greater reduction in total wine acidity. However, it is necessary to maintain the calcium carbonate concentration within 0.1% since excessive amounts of calcium carbonate can have a negative effect on wine quality.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2005.11a
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• pp.154-157
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• 2005

MLRS is the weapon system which has been mass-produced since 2004. MLRS launch tube has developed and produced independently refer to the facilities and process condition of General Dynamics Co, USA. The purpose of this research is base establishment for the launch tube performance improvement and application of another weapon system. Research performed about material property, process condition, and structural property.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.8 s.173
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• pp.64-70
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• 2005

The development of an accurate and energy saving pneumatic regulator that may be applied to a variety of practical pressure control applications is described in this paper. A novel modified pulse width modulation(MPWM) valve pulsing algorithm allows the pneumatic regulator to become energy saying system. A comparison between the system response of conventional PWM algorithm and that of the modified PWM(MPWM) algorithm shows that control performance is almost the same, but energy saving is greatly improved by adopting this new MPWM algorithm. The effectiveness of the proposed control algorithm are demonstrated through experiments with various reference trajectories.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1998.05a
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• pp.89-93
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• 1998

농가보급형 비닐온실(1-2W형)은 농촌진흥청에서 '92년 4월에 폭 7m, 측고 2.7m, 동고 4.8m로 개발하여 각 시ㆍ군에 설계서를 배포하였으며 '95년 3월 자재일부와 동고의 높이를 수정하였고, 개량아치단동형(1-lS)과 '94년 6월에 개발된 한국형 유리온실과 함께 농민들이 가장 선호하는 시설형태 중 하나이다. (중략)

• 전기의세계
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• v.39 no.2
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• pp.12-24
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• 1990

고분자는 전기장 내에 놓이게 되면 분극현상과 전하주입현상이 일어나며 절연체의 절연수명은 분극현상보다 전하주입에 의해 형성된 공간전하에 의하여 크게 좌우된다. 공간전하에 관한 연구에 있어서 공간전하의 정화한 측정 자체도 어려운 문제인 데, 최근에 개발된 방법인 압력펄스파 방법이 있다. 이 방법은 매우 짧은 폭의 펄스가 절연체를 통과하면서 얻은 공간전하에 관한 정보를 de convolution에 의한 후속신호처리하면 절연체내에 존재하는 전하의 공간분포에 따라서 전체전하량 등을 구할 수 있다. 고전압용 전선에 쓰이는 절연물질에서는 사용되는 전압의 종류에 따라 다른 형태의 문제점이 발견된다. dc절연에 있어서는 전압의 극성이 갑자기 바뀌는 polarity reversal에 의한 절연파괴가, 그리고 ac절연에서는 소위 트리잉 현상이라고 불리우는 전기적인 열화반응에 의한 절연체의 파괴 현상이 중요시되고 있다. 이들 모두 공간전하의 축적이 심할 수록, 그리고 기공 또는 그밖에 전기집중현상을 일으킬 수 있는 요인이 많을 수록 절연체의 절연수명을 급격히 감소한다. 따라서 절연수명을 향상시키기 위하여는 공간전하의 축적을 방지해야 하는데, 여기에는 전기적인 측면에서의 노력과 아울러 고분자 자체의 개량등의 노력도 함께 있어야 한다.