• Korean Journal of Environmental Agriculture
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• v.24 no.3
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• pp.261-269
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• 2005

To investigate effects of fanning practice and $NO_3-N$ contents of groundwater in intensive horticultural greenhouse area of Yeongnam province, the groundwater samples from 1,370 sites were collected and analyzed. In addition, cultivation year, crops, desalinization methods, amounts of manure application, tube well depth and soil texture with clay contents were observed. Of the investigated sites, 19.7% of shallow groundwater and 1.3% of confined groundwater were exceeded over $10mg/{\ell}$ as the $NO_3-N$ drinking limit value, respectively. $NO_3-N$ concentration in groundwater was highly significantly correlative with clay content $(r=-0.241^{**})$, well depth $(r=-0.228^{**})$ and cultivation duration $(r=0.104^*)$, respectively. In case of desalting crop method being executed for desalinization of greenhouse soil, the $NO_3-N$ value of groundwater was lower than any other desalinization method. The fact that $NO_3-N$ contents of confined groundwater was affected by shallow groundwater was clarified by that $NO_3-N$ contents in shallow were significantly correlative with the confined groundwater $(r=0.532^{**})$.

• Korean Journal of Food Science and Technology
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• v.30 no.1
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• pp.82-89
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• 1998

This study was performed to elucidate the purification and characterization of pretease from saewoo-jeot, a Korean traditional salt-fermented shrimp product. The protease in saewoo-jeot (Acetes japonicus) were extracted, desalted through electrodialysis and purified by ammonium sulfate fractionation, Sephadex G-100 gel filtration and DEAE-cellulose column chromatography. Purified enzyme had specific activity of 8.4 unit/mg, yield of 14% and purification fold of 9.8. Purified enzyme was confirmed as single band protein by polyacrylamide gel electrophresis and the molecular weight was estimated to be about 24 kDa. The optimal pH and temperature for the enzyme activity were 8.0 and $40^{\circ}C$, respectively. The range of its stability to the pH and temperature were 7.0 to 10.0 and $30^{\circ}C\;to\;60^{\circ}C$, respectively. The activity of enzyme to synthetic substrate showed BAPNA and TAME. The enzyme was activated significantly by manganese ions, while inhibited by STI, TLCK. metals $(K^+,\;Li^+,\;Na^+,\;Ca^{++},\;Co^{++},\;Cu^{++},\;Mg^{++},\;Ba^{++},\;Hg^{++},\;Zn^{++},\;Fe^{+++})$. The Km value of the enzyme was $5.1{\times}10^{-7}\;M$ to hammersten casein. It's suggested that purified protease from saewoo-jeot seemed to be trypsin-like enzyme.

• Journal of the Korean GEO-environmental Society
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• v.14 no.7
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• pp.51-56
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• 2013

Recently, a top record of hourly-based rainfall has been changed annually and flood damages of road have increased. To solve this problem, pavements for drainage were developed and practically constructed but there was no considerations on sub-base. In this research, we proposed standard for distribution of particle size of sub-base to consider strength characteristic and drainage property. We focused to compare coefficients strength and permeability by laboratory tests. Prior to tests, 4 samples were selected under the consideration on the international or domestic design guideline. In the tests, strength characteristics were compared with resilient modulus. Also, permeability characteristics were compared with coefficient of upward and downward permeability. Resilient modulus was determined with MR test using cyclic triaxial testing system. Two permeability tests were carried out. One is variable head permeability test for downward drainage and the other is Rowe Cell test for upward drainage. In the case of Rowe Cell test, middle-sized sampler with 150mm diameter was used for this study. Consequentially, we tried to find the optimum distribution of particle size to satisfy both of strength and permeability characteristics for sub-base.

• Journal of the Korean Geosynthetics Society
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• v.12 no.3
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• pp.65-73
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• 2013

The information of cut slope in Mt. Jang area, Busan is investigated in order to construct the Slope Management System in Urban Area. The slope inspection sheet is made to record the characteristics for cut slopes, and that is capable to be inputted slope information systematically. The cut slopes in Mt. Jang area are consisting of 69 slopes. Most of the cut slopes are constructed in cutting slope and retaining wall (CR). The cut slopes located in housing facilities are 46 slopes, and the slopes located in school facilities are 12 slopes. The traverse of cut slopes is mainly ranged from 50 m to 150 m, and the height is mainly ranged from 10 m to 20 m. The slopes combined with soil and rock are mostly distributed. The retaining wall was installed in the toe part of cut slope in order to increase the slope stability, and the additional reinforcement methods including the anchor, drainage, preventing rock fall, shotcrete and vegetation were installed at the toe part of cut slopes.

• Magazine of the Korean Society of Agricultural Engineers
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• v.39 no.1
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• pp.75-82
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• 1997

건설기술과 산업의 발전에 따라 구조물은 대형화되어 가고, 건설공사의 급격한 팽창으로 골재 수용량이 급증함에 따라 천연골재자원은 점차 부족현상을 면치 못할 처지에 있다. 또한, 무리한 천연골재의 채취는 자연환경을 훼손시킬 뿐만 아니라 자연보호 측면에서도 심각한 공해문제로 대두되고 있어 공급량 부족현상은 날로 심화되고 있다. 이에 세계 몇몇 나라에세는 산업부산물을 이용한 골재 생산으로 공해예방과 폐기물 활용방법을 연구하고 있다. 산업부산물중 플라이 애쉬 생산량은 전 세계적으로 매년 약 2억여톤에 달하고 있으나 이중 일부만 활용되고 있는 실정이다. 이와같은 부산물을 활용하기 위한 일환으로 산업부산물인 PFA(Pulverized Fuel Ash)로 만든 인공경량골재의 년생산량이 영국은 600,000$m^3$, 미국은 300,000$m^3$이며, 매년 증가주세에 있다. 고성능 경량골재 콘크리트는 단위중량의 증가없이 내구성과 강도를 향상시켜 실용화 측면에서 경제적인 효과가 있으며, 플라이 애쉬로 만든 경량골재는 시멘트와의 친화력이나 접착면에서 우수한 것으로 알려져 있다. 본 시험에 사용한 골재는 플라이 애쉬로 만든 인공경량 조골재와 강모래이고, 결합제로서 프틀랜드 시멘트를 사용하였다. 부수적인 결합재로서는 플라이 애쉬, 슬래그, 실리카 흄을 사용하였으며, 고성능 경량골재 콘크리트를 개발코자 재령 28일과 180일의 압축강도가 각각 50MPa와 60MPa가 되도록 배합설계를 하였다. 본 연구에서는 플라이 애쉬, 슬래그, 시리카 흄과 같은 산업부산물을 혼입했을때 경량골재 콘크리트의 압축강도, 휨강도, 동탄성계수, 공극체적, 공극률, 단위중량, 공극 크기별 분포등의 변화를 실험적으로 구명하여 재반 구조용 콘크리트에 활용하기 위한 기초자료를 마련코저 한다.있어 특정한 발육단계의 난포 사망기전을 연구하기 어렵다. 또한 난포는 생체 내에서 다양한 호르몬을 동시에 분비하기 때문에 특정한 난소국부호르몬이 사망기전에 미치는 영향을 조사하기 힘든 점이 있다. 최근 들어 난포체외배양이 다양하게 개발되면서, 이러한 어려운 점을 극복할 수 있게 되었다. 본 논문은 각 발육단계의 난포를 절단해 체외배양하면서, apoptosis DNA 절단 현상을 이용하여 각종 난소국부 호르몬들이 난포발육단계별로 사망기전에 미치는 영향을 요약해 보였다. 난포는 발육하면서 점차 복잡한 호르몬 경로를 생존을 위해 필요로 한다. Prevulatory난포생존에 필요한 난소국부호르몬들은 early antral 단계의 난포에서는 그 미치는 영향이 감소되다가 preantral단계의 난포에서는 영향을 전혀 미치지 못했다. 단지 예외는 cGMP처리로써, 세포내 cGMP수준을 일정하게 유지시켜주는 것이 난포발육단계에 무관하게 생존에 중요한 인자로, 장래 연구는 난포 세포내의 cGMP수준을 조절하는 기작을 규명하는데 있을 것이다.인정되지 않았다. 7. 농지보전 처리구인 배수구와 초생수로구는 비처리구에 비해 낮은 침두 유출량과 낮은 토양유실량을 나타내었다.구보다 14% 절감되는 것으로 나타났다.작용하는 것으로 사료된다.된다.정량 분석한 결과이다. 시편의 조성은 33.6 at% U, 66.4 at% O의 결과를 얻었다. 산화물 핵연료의 표면 관찰 및 정량 분석 시험시 시편 표면을 전도성 물질로 증착시키지 않고, Silver Paint 에 시편을 접착하는 방법으로도 만족한 시험 결과를 얻을 수 있었다.째, 회복기 중에 일어나는 입자들의 유입은 자기폭풍의 지속시간을 연장시키는 경향을 보이며 큰 자기폭풍일수록 현저했다. 주상에서 관측된 이러한 특성은 서브스톰 확장기 활동이 자기폭풍의 발달과 밀접한 관계가

• Journal of KIISE:Software and Applications
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• v.30 no.1_2
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• pp.58-72
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• 2003

The objects generated by the keyword new in Java are automatically managed by the garbage collector Inside Java Virtual Machine (JVM) not like using the keywords free or delete in C or C++ programming environments. This provides a means of freedom of memory management burden to the application programmers. The garbage collector however. inherently has its own run time execution overhead. Thus it causes the performance degradation of JVM significantly. In order to mitigate the execution burden of a garbage collector, we propose a novel way of dynamic memory management scheme in Java environment. In the proposed method, the application programmers can explicitly manage the objects In a simple way, which in consequence the run-time overhead can be reduced while the garbage collector is under processing. In order to accomplish this, Java application firstly calls the APIs that arc implemented by native Jana, and then calls the subroutines depending on the JVM, which in turn support to keep the portability characteristic Java has. In this way, we can not only sustain the stability in execution environments. but also improve performance of garbage collector by simply calling the APIs. Our simulation study show that the proposed scheme improves the execution time of the garbage collector from 10.07 percent to 52.24 percent working on Mark-and-Sweep algorithm.

• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.615-623
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• 1998

The garlic juices were extracted and concentrated by heating at $90^{\circ}C$, by using a rotary vacuum evaporator at $45^{\circ}C$, or by freezing at $-50^{\circ}C$ until the volume was reduced to 70% of the original volume. The concentrated juices were kept at $4^{\circ}C\;or\;25^{\circ}C$ for 60 days and the changes of bacteria and color were monitored every 10 days. Flavors of the raw garlic juices, concentrated garlic juices, and garlic powder by hot-air drying were analyzed monthly using GC and GC/MS. The CFUs/mL of mesophilic and psychrotrophic bacteria in the garlic juice concentrated at $90^{\circ}C$ were lower about 1 to 2 log cycles than those of other concentrated juices. Hunter L, a, and b values in the raw garlic raw juice and the juice concentrated at $-50^{\circ}C$ significantly increased at the beginning of storage, in particular, when they were stored at $25^{\circ}C$. The garlic juice concentrated at $45^{\circ}C$ showed relatively low L value but the juice concentrated at $90^{\circ}C$ showed high a value. The main peaks in chromatograms of volatile components identified by GC/MS were 3,3'-thiobis-1-propene, di-2-propenyl disulfide, 3-(methylthio)-1-propene in the raw garlic juice and the concentrated juices, and the juices concentrated at $45^{\circ}C\;or\;-50^{\circ}C$ showed relatively high preservation of garlic flavor.

• Journal of the Korea Concrete Institute
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• v.20 no.4
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• pp.495-502
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• 2008

To analyze the growth of SOB(Thiobacillus novellus) and biochemical corrosion of concrete, simulation test method and device were developed, and basic conditions for SOB growth were established. Two types of simulation tests were conducted according to a transplant method and a concentration of $H_2SO_4$. As a result, the SOB growth in distinct manners and antibiosis of specimen were observed. In the case of the specimens indirectly transplanted with SOB through culture solution submersion at a hydrogen sulfide level of 120 ppm, the rapid activation of SOB and the resulting sulfuric acid production were observed. However, SOB were shown to grow rapidly and then die out in a relative short period of time. Meanwhile, in the case of the specimens directly transplanted with SOB at a hydrogen sulfide level of 50 ppm, the long-term growth of SOB was possible, but the production of sulfuric acid by SOB did not progress. In the case of the antibiotic metal-mixed specimens, SOB with destroyed cell membranes and internal organizations were observed.

• Food Science and Preservation
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• v.21 no.4
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• pp.500-505
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• 2014

This study investigated the effects of the steeping condition and salinity stress on the quality properties of germinated black soybean. The absorbed water content increased drastically in six hours with the increase in the steeping time and the temperature. The pH decreased as the steeping temperature increased. A gradual increase in the dissolution of the anthocyanin was observed with the steeping time. The adequate steeping conditions were found to have been six hours at $25^{\circ}C$, which showed the needed absorbed water content within a short time. The germination percentage of the black soybeans decreased with the increase in the NaCl concentration. The pinitol and total phenolics contents showed the highest values under the concentrations of 0.7% and 0.3-0.5% NaCl, respectively. The flavonoid content was highest at the 0.1% NaCl concentration. Consequently, the salinity stress during the germination of the black soybeans enhanced the pinitol content and lowered the blood sugar, which gives it an advantage as a functional food material.

• Korean Journal of Plant Resources
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• v.30 no.4
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• pp.343-351
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• 2017

Plant extracts were screened for antifungal activity against major plant pathogens, Botrytis sp., Collectotrichum sp., Alternaria sp. and Cylindrocarpon sp. using 96-well microdilution method. Among the 662 methanol extracts from 401 plant species, 36 extracts showed complete inhibition of spore germination against at least one of four pathogenic fungi. Extracts of Morus alba twig and Sophora flavescens root showed minimum inhibition concentration (MIC) at $1,250{\mu}g/ml$ against Botrytis sp.. Extracts of Chloranthus japonicus root showed MIC at $1,250{\mu}g/ml$ against Collectotrichum sp.. Extracts of Glycyrrhiza uralensis aerial part, Inula helenium root and Menispermum dauricum root showed MIC between 625 and $1,250{\mu}g/ml$ against Alternaria sp.. G. uralensis aerial part and I. helenium root showed MIC at $1,250{\mu}g/ml$ against Cylindrocarpon sp.. Specifically, the extracts of Agrimonia pilosa root, Angelica tenuissima root, Asarum sieboldii root, Campsis grandifolia leaf and twig, Cnidium officinale root, Dictamnus dasycarpus root, G. uralensis aerial part, I. helenium root and M. alba twig completely inhibited spore germination at lower than $5,000{\mu}g/ml$ against all of four pathogenic fungi. Two methanol extracts from G. uralensis aerial part and M. alba twig may used as a candidate to develop into effective disease management materials in plant cultivation.