• Journal of Korean Society of Forest Science
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• v.94 no.3 s.160
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• pp.197-204
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• 2005

This study was conducted to investigate the effect of tsunami which occurred in coastal area of the East Sea in Korea, the function of coastal forest for the reduction of tsunami's speed and energy, and the non-structural measures through the research data of tsunami in Japan. The results showed that tsunami which occurred in the East Sea in 1983 and 1993 reached coastal area of Korea one hour and fifty minutes later from Japan, and caused a loss of lives and property and flooding damage. If 60 m width of coastal forest was formed, the speed was decreased by 30%, the energy by 10%. Therefore, the width of coastal forest must be at least 60 m, of which the stand structure is the multiple-layered forest of mixed-forest, and the wave preventing measures have to be constructed together. In addition, non-structural measures as tsunami warning and survival strategies must be prepared.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.1
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• pp.24-29
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• 1986

Experiments were conducted to know the inorganic compound absorption of leaf, and the organic component, oil content, fatty acid composition of seeds by different fertilizer levels and growth stage of Pungn-yeonggage. Ripening rate and seed yield were highest under the standard of nitrogen fertilizer level. Nitrogen and potassium amount of leaves were highest at 20 days after seedlings, but there was no difference in phosphate between growth stages. Absorptions of nitrogen and potassium were increased by applying double amount of nitrogen fertilizer. Oleic fatty acid content was found highest under the double amount of nitrogen, phosphate and potassium fertilizer level, and linoleic fatty acid content was increased with double amount of phosphate fertilizer level.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.2
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• pp.1-8
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• 2020

In the case of power plant facilities, seismic stability of non-structural elements is important. In particular, Cabinet structures to which electrical equipment is attached, should have functional safety against earthquakes. Therefore, in this study the dynamic characteristics of non-structural elements inside existing power plant buildings were identified and the response level generated during dynamic behavior was analyzed. In addition, The steel plate dampers were adopted and adjusted to suit the size of the target equipment. In order to derive the optimal seismic reinforcement, the variables according to the attachment location were set and the responses were analyzed by the seismic movement input before and after reinforcement.

• Journal of Korean Ophthalmic Optics Society
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• v.6 no.1
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• pp.43-47
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• 2001

The classifying distribution by the Spherical lens and Aspherical lens was middle myopic, middle myopic astigmatism middle mixed astigmatism compared. The refractive erroeye spherical lens were S-3.00 ~ S-6.00Dptr for the middle myopic 16%, S-6.00Dptr 19%, S-3.00C-0.50(90.180) ~ S-6.00C-2.00Asix(90.180)57%, S-3.00C+0.50(90.180) ~ S-6.00C+2.00Axis(90.180) 8% for the compound myopic astigmatism. Aspherical lens were S-3.00 ~ S-6.00Dptr for the middle myopic 31%, S-6.00Dptr 36%, S-3.00C-0.50(90.180) ~ S-300C-2.00Axis(90.180) 21%, S-3.00C+0.50(90.180) ~ S-3.00C+2.00Axis(90.180)12%, for the compound hyperopic astigmatism.

• Composites Research
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• v.24 no.3
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• pp.31-38
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• 2011

In this paper, a novel hybrid composite shield to protect space structures from hypervelocity impact of micrometeoroid and space debris is proposed. The finite element model of the proposed shield was constructed and finite element analysis was conducted to approximate the energy absorption rate. Before the final model analysis, analysis of each component including the aluminum plate, PMMA plate, and intermediate layer of fabric was performed, verifying the finite element model of each component. The material properties used in the analyses were predicted material property values for high strain rates. The analysis results showed that, other than the fabric, the energy absorption rate of each component was in agreement. Afterwards, the finite element model of the hybrid composite shield was constructed, where it was analyzed for the restrained and unrestrained fabric boundary condition cases. Through the finite element analysis, the fiber pullout mechanism was realized for the hybrid shield with free boundary inserted fabric, and it was observed that this mechanism led to energy absorption increase.

• Journal of Internet Computing and Services
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• v.10 no.4
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• pp.189-198
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• 2009

Unstructured peer-to-peer systems are most commonly used in today's internet. But file placement is random in these systems and no correlation exists between peers and their contents. There is no guarantee that flooding queries will find the desired data. In this paper, we propose to cluster nodes in unstructured P2P systems using the agglomerative hierarchical clustering algorithm to improve the search method. We compared the delay time of clustering the nodes between our proposed algorithm and the k-means clustering algorithm. We also simulated the delay time of locating data in a network topology and recorded the overhead of the system using our proposed algorithm, k-means clustering, and without clustering. Simulation results show that the delay time of our proposed algorithm is shorter compared to other methods and resource overhead is also reduced.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.4
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• pp.332-339
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• 1991

본 시험은 1968-1990년까지 23년간을 동일시험구에서 무비구를 비롯하여 무질소구, 무인산구, 무가리구, 3요소구, 3요소+유기물구(퇴비 또는 생고), 3요소十석회구를 설치하고, 1990년수도품종 ‘진흥’을 공시하여 그 수량생산성과 미질의 외관 및 이화학적특성을 조사하므로써 장기간에 걸친 시비법이 수량과 양질미생산에 미치는 영향을 검토한 바 그 결과를 요약하면 다음과 같다 1 수량생산성은 3요소구에 비해 3요소+유기물구에서 3-7%의 증수효과가 있었으며, 1 증수요인은 수수와 1수당입수의 증가였다. 2. 무가리구의 수량은 85%로 등숙률의 저하가 감수요인이며, 무인산구는 74%로 수수의 감소가 감수요인이며, 무질소구와 무비구는 59-33%로 수수와 1수립수의 현저한 감소가 감소요인이었다. 3. 미질의 외관적 특성은 무비, 무질소, 무인산구에서 수량은 크게 낮은 반면에 완전미율이 높고 동할미, 심복백미율이 현저히 적으며 3미립의 투명도도 높아 양질의 외관을 보였다. 이에 대해 고수량을 보인 3요소＋유기물구(퇴비, 생고)에서 완전미율이 낮고 동할미, 심복백미율이 높고 투명도가 낮아 외관적 미질이 저하하는 경향이었다. 4 미질검정으로 이용되고 있는 물리적 특성인 알칼리붕괴성과 gel consistency는 처리간 차이를 인정할 수 없었다. 5. 식미의 량부로 평가하고 있는 미립의 화학적 특성은 처리간 차이를 인정할 수 있었다. 즉 단백질함량은 3요소＋유기물구에서 높고 무비구에서 낮았으며 Mg, Mg/K, Mg/KㆍN, Mg/KㆍN\ulcornerAmylose는 무비, 무질소, 무가리구에서 높고, 3요소+유기물. 3요소+석회구에서 낮았다 6. 이상과 같은 결과로 미루어 본 실험에 시용된 절대질소량은 많지 않음에도 불구하고 3요소＋유기물구는 유기물 분해에 따른 질소의 추비적 효과가 나타나서 무비, 무질소구에 비해 동할미, 심복백미 등 미립의 외관적 특성을 저하시키고, 단백질함량은 높이고 Mg/K\ulcornerNㆍAmylose를 낮추어 식미를 저하시키는 것으로 해석된다 7. 취급특성으로서의 흡수율, 취급액요드정색도, 취급용액출고형물은 처리간 명백한 경향을 발견할 수 없었다.

• Journal of Bio-Environment Control
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• v.6 no.2
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• pp.97-102
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• 1997

To investigate the effect of nitrogen level on the yield and quality of watermelon(Citrullus vulgaris S. cv. Bocksubak), N levels of 250, 200, 140, and 0kg/ha with the conventional amount of K and P supply non-fertilization treatments were compared one anther. Plant height, leaf area, fresh weight and dry weight were better in nitrogen application treatments than no nitrogen and non- fertilization treatments. But there was no significant difference between nitrogen levels. Yield and fruit setting ratio were the highest in N level of 140kg/ha. Fruit weight was increased by N application, and soluble solids content was the highest as 12.5 $^{\circ}$Bx in N level of 140kg/ha. Nitrogen content of leaves was increased with the applied nitrogen amount and highest at the middle stage of growth. P content was no significant difference between treatments. Ca content was increased with the applied nitrogen amount and highest at the late stage of growth.

• Korean Journal of Plant Resources
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• v.15 no.1
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• pp.67-71
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• 2002

In order to determine the optimum level of three major fertilizers for Saururus chinensis, we applied to the soil at a rate of N(0, 4, 7, 10kg/10a), P$_2$O$\_$5/(0, 1.5, 3, 4.5kg/10a) and K$_2$O(0, 3, 6, 9kg/10a) prior to seeding. Regarding physical properties after the application, the values of pH, OM, Mg, CEC and EC were higher than those of the pre-application, but the contents of P$_2$O$\_$5/, K and Ca were lower. With application of three major fertilizers, dry weight of leaves per 10a was 26∼108kg greater than that of control(281kg) and dry weight of root tuber was higher by 19∼157kg than that of control(610kg). In regression equation of fertilizer recommendation for two-year-old Saururus chinensis, the optimum level of N-P$\_$2/O$\_$5/-K$\_$2/O fertilizer was determined by 7.1, 2.5, 4.2kg/10a, respectively.

• Korean Chemical Engineering Research
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• v.45 no.6
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• pp.611-618
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• 2007

We demonstrate the sol-gel coating technique of colloidal clusters for producing hollow micro-particles with complex morphologies. Cross-linked amidine polystyrene (PS) microspheres were synthesized by emulsifier-free emulsion copolymerization of styrene and divinylbenzene. The amidine PS particles were self-organized inside toluene-in-water emulsion droplets to produce large quantities of colloidally stable clusters. These clusters were coated with thin silica shell by sol-gel reaction of tetraethylorthosilicate (TEOS) and ammonia, and the organic polystyrene cores were removed by calcination at high temperature to generate nonspherical hollow micro-particles with complex morphologies. This process can be used to prepare hollow particles with shapes such as doublets, tetrahedra, icosahedra, and others.