• 한국농공학회지
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• 제25권2호
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• pp.35-41
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• 1983

This research is mainly to deal with the effects of submergence treatment on the grain yields of two rice plants, local variety, "Akibare" and Tongil line variety, "Milyang 23". The results obtained are summarized as follows. 1. According to the rice products of each plot the grain yield index was smallest in the plot treated at the early heading stage. The index of the next order became smaller in order of late flowering stage, late reduction division stage, milk ripe stage and dough ripe stage etc. The submerged stage at which the damages were smallest was tillering stage. Under the condition of two thirds or one third submerged depth of plant height, few differences in the grain yield index between Milyang 23 and Akibare was found, but except rooting stage, the damages of milyang 23 by whole submergence during growing period were mostly greater than those of Akibare. Especially the grain yield index of early heading stage at which the damages by whole submergence was most serious showed 45 percentage for one day submergence, 31 percentage for 3 days and 0.7 percentage for 7 days in Akibare plots, and 26.7% percentage for one day submergence, 7.9 percentage for 3 days and none for 7 days in Milyang 23 plots. 2. All the factors such as submerged stage, submerged depth and submerged period in this experimental test were highly recognized significance. The factors of the submerged depth and duration influenced on greater damages than the others. According to the difference in grain yield between plots, the larger the submerged depth and duration were, the larger the significant difference appeared. And between the treated levels at other submerged stages except both early tillering stage and most active tillering stage, the significance in the differences in grain yield was recognized, while only the submergence at early heading stage showed the most serious damages. 3. The decreased rate of grain yield for one day submergence at early heading stage indicated that in case of whole submergence of plant height it was 73 percentage in Milyang 23 plot and 55 percentage in Akibare plot, and in the event of two thirds and one third submergences of it, 20 percentage and 10 percentage in both Mulyang 23 and Akibare plots respectively. Therefore, the current criteria for planning project that restricted allowable submergence duration of more than 30cm submerged depth to 24 hours, should be amended not to exceed the submerged depth of 60cm when the duration of more than allowable submerged depth of 30cm will be limited to 24 hours, or within the limits of 12 hour submerged duration for locai variety and of less than 12 hour duration for Tong-illine variety as long as possible in case that submerged depth will be allowed to more than 60cm depth.ore than 60cm depth.

• 한국패류학회지
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• 제27권2호
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• pp.99-105
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• 2011

남해안 내만해역에서 인공부착판 투입시기와 투입기간에 따른 군집구조의 차이를 보고자 하였다. 거제도 장목만에서 2007년 3월에서 10월에 이르는 기간 동안 매월 PVC 재질의 인공부착판을 수심 50 cm에 수직방향으로 투입하였다. 2007년 11월에 저서동물이 부착된 PVC판을 회수하여 부착생물군집을 조사한 결과 지중해담치는 3월에서 7월에 투입된 부착판에서 우점종으로 출현하였고, 석회관갯지렁이와 주름멍게는 5월 이후 10월까지 투입한 부착판에서 우점종으로 남았다. 주걱따개비와 다발이끼벌레류는 6월-9월 사이에 투입한 부착판에서 우점하였다. 실험종료 시에 회수한 부착판에서의 분류군별 개체수와 습중량은 지중해담치의 우점으로 3월-7월 사이에 투입된 부착판에서 최대치를 보였다. 종간 경쟁으로 인하여 최대가입시기와 우점시기가 일치하지 않은 부착생물들이 나타났고, 투입기간과 생물량이나 개체수 간에는 가입시기의 차이로 인하여 뚜렷한 관련성을 보이지 않았다. 투입시기별 및 투입기간별로 특정 저서생물이 우점종으로 출현하였는데, 이는 유생 공급을 결정하는 가입시기와 나중에 유입되는 유생을 배제하는 종간경쟁에 의해 최종 부착생물군집의 조성에 중요한 결정 요인이 되는 것으로 나타났다.

• 한국환경과학회지
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• 제20권11호
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• pp.1457-1464
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• 2011

In this study, the method of estimating hydrologic information (water depth, submerged period etc.) on the proper selection of construction point and scale as well as vegetation type suggested for the design of natural riparian rehabilitation structure. Long-term comprehensive watershed model SWAT-K(Korea) was applied to this purpose. Flow duration analysis was conducted to analyze the hydrologic characteristics of Pyungchang watershed at which the 'bangtul' construction method was tested. For this purpose 20 years (1989-2008) rainfall runoff analysis was carried out. Based on the simulated daily streamflow data, flow duration curve was made to analyze the flow characteristics, and the water depth hydrograph was made to analyze the water depth distribution at the cross section. Finally, the information for the selection of proper vegetation according to the submerged period is suggested.

• 한국안전학회지
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• 제17권3호
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• pp.61-65
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• 2002

A study on the characteristics of electric shock in fresh water due to the leakage of submerged electric facility is conducted by using a reduced scale model at a scale of 1:10 in laboratory. Electric potential as a function of distance from leakage source, type of the leakage source, magnitude of the source voltage, submerged depth and diameter of a copper rod electrode is measured. On the basis of safety standard, separation for guarantee of safety is determined by the measured potential. Also supposing that body resistance is 500［$\Omega$］, the human reaction was estimated by calculating body current for some shock duration. Thus, in this paper, the hazard of the electric shock is assessed by introducing representative safety factors, body voltage and body current due to leakage source.

• 한국주거학회논문집
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• 제20권3호
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• pp.69-76
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• 2009

The Storm Water Management Model(SWMM) by EPA is a dynamic rainwater-runoff simulation model used for single event or long-term simulation of runoff quantity and quality from primarily urban areas. The SWMM simulation program is operated by the site area, the weather date, conduit plan etc. on reference region. The purpose of this study was to analyze flood area, the duration of flooded and surcharged on the reference region. Without rainwater stored tank, the area of flooded and surcharged on reference area is similar to the area of reference region. But, With rainwater stored tank, the area of flooded and surcharged on reference area is much reduced compared to without rainwater stored tank. According to SWMM simulation results, the rainwater stored tank is located closer to site is more effective for reduction of duration of flooded and surcharged and flow rate.

• 한국식품저장유통학회지
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• 제6권3호
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• pp.292-296
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• 1999

땅콩의 착협비대기인 '98. 8. 5 - 8. 6 사이 2일간 207 mm에 달하는 집중호우에 의거 침수피해가 발생된 지역에서 약 1개월 후 시료를 채취하여 땅콩의 생육, 수량 및 품질변화에 대하여 조사한 결과, 주경장, 분지장, 생체중 등 지상부 생육과 종실수량은 침수일수가 길수록 현저히 감소되었고, 침수기간이 1일 정도 짧아도 침수기간 3일과 큰 차이없이 피해가 컸으며 땅콩종실의 저장기간중 지질의 산패율은 침수일수가 길수록 산패가 빨랐고, 불포화지방산인 Linoleic acid 조성비도 낮아 품질이 다소 저하되는 경향이었다. 침수일수에 따른 식물체의 지상부 무기성분은 질소, 인산 및 고토의 함량은 침수일수가 길수록 증가되었으나 칼리함량은 감소되었다. 침수피해지의 토양 분석결과 토양중 유기물, 인산 등 각종양분의 함량이 현저히 적어 무침수지에 비하여 양분용탈 및 유실이 심하여 비옥도가 크게 떨어졌다. 따라서 홍수에 의한 침수일수가 길수록 땅콩식물체의 무기성분함량. 품질 및 토양 비옥도에 크게 영향을 미침을 알 수 있었다.

• 한국잠사곤충학회지
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• 제18권2호
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• pp.107-110
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• 1976

In silk reeling process the carry-over cocoons must be submerged in the reeling baths filled with reeling water and left until reopening the operation. Under the detention the carry-over cocoons are apt to decay without any antiseptic treatment. Thus an useful antiseptic for the cocoons is urgently needed, and various antseptic agents have been tested for their applicability to the process. However, such an useful agent has not been developed yet. Formalin has been the only chemical used for antisepticizing carry-over cocoons, although it has many defects as the antiseptic for the cocoons. In these circumstances, recently we newly prepared an antiseptic useful for preventing the carryover cocoons from decaying. We named the new antiseptic preparation "Swi-Se-Yo." The Korean term "Swi-Se-Yo" literally means "please take a rest". Through a series of experiments with Swi-Se-Yo we obtained the following results: 1) Swi-Se-Yo, in 0.05% aqueous solution, exerted a good antiseptic effect on the boiled Cocoons submerged in the reeling baths and the effect lasted for 45 hours. The duration of the effect is about two times longer than that of Formalin. 2) The percentage of cocoon reel ability of the carry-over cocoons treated with Swi-Se-Yo was 6% higher than that of Formalin and was equal to that of flowing cold water. 3) The percentage of raw silk yield of the carry-over cocoons treated with Swi-Se-Yo was almost equal to that of Formalin and to that of flowing cold water. 4) The quality of raw silk of the carry-over cocoons treated with Swi-Se-Yo is the same as that of flowing cold water. Besides the above favourable results, Swi-Se-Yo has many advantages as an antiseptic. Chemically it is very stable. Its antimicrobial action is very strong and the spectrum is very broad. It can be available in water-soluble powder and in small bulk. And it is not harmful to human and domestic animals. Considering these profitable properties of Swi-Se-Yo, it will have a good reputation as a carry-over cocoon antiseptic. (The chemical composition and manufacturing method of Swi-Se-Yo will be published in the near future.)

• 한국작물학회지
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• 제53권4호
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• pp.440-446
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• 2008

상시담수 하에서 발아 및 안정적인 입모를 확보하는 것은 담수직파에서 매우 중요한 일이다. 일반적으로 담수 조건에 서는 유묘생장이 억제되지만, 담수 처리 시 초기생육이 우수한 익산429와 담수 처리 시 생육이 저조하며 생존율이 낮은 Woodrose 2품종에 대해 발아 및 초기생육기간 담수 처리하여 혐기대사와 관련된 ADH활성과 항산화효소들의 변화를 관찰하였다. 1. 담수 처리 시 벼는 유아만 신장하며 뿌리는 신장하지 못했고, 익산429가 Woodrose보다 담수상태에서 생존기간이 길었고 생장도 빨랐다. 그러나 무 처리에서는 Woodrose의 생육이 빨랐다. 2. ADH활성은 담수 처리 시 무 담수에 비해 급격히 증가하였고, 익산429가 Woodrose보다 활성이 오래 유지되었는데, 처리 7일째는 익산429가 무처리에 비해 약 7배, Woodrose는 약 2.5배 증가하였다. 4. SOD, POX, CAT 활성 모두 담수 처리에서 무 담수보다 낮았다. 그러나 SOD는 담수시 무 담수에 비해 크게 활성이 낮지는 않았으며 품종 간에는 익산429의 활성이 무 담수 및 담수 처리 모두 Woodrose보다 높았고 담수 시에도 익산429가 Woodrose보다 높게 유지되었다. POX 활성변화는 담수시 익산429가 지속적으로 증가한 반면 Woodrose는 큰 변화가 없었다. CAT활성은 담수 처리 초기부터 아주 낮은 활성을 보여 처리기간 동안 거의 증가하지 않았으나 무 담수시에는 3일까지 활성이 크게 증가하였다. 따라서 담수 처리 시 발아 및 초기생육기간 동안 담수내성이 약한 품종에서 SOD와 POX의 역할이 크고 ADH활성이 높게 유지되어 에너지를 공급할 수 있는 품종이 담수 시 초기생육에 유리할 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제16권6호
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• pp.863-869
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• 2006

The behavior of submerged membrane bioreactor (SMBR) filtration systems utilizing rapid air backpulsing as a cleaning technique to remove reversible foulants was investigated using a genetic algorithm (GA). A customized genetic algorithm with suitable genetic operators was used to generate optimal time profiles. From experiments utilizing short and long periods of forward and reverse filtration, various experimental process parameters were determined. The GA indicated that the optimal values for the net flux fell between 263-270 LMH when the forward filtration time ($t_f$) was 30-37 s and the backward filtration time ($t_b$) was 0.19-0.27 s. The experimental data confirmed the optimal backpulse duration and frequency that maximized the net flux, which represented a four-fold improvement in 24-h backpulsing experiments compared with the absence of backpulsing. Consequently, the identification of a region of feasible parameters and nonlinear flux optimization were both successfully performed by the genetic algorithm, meaning the genetic algorithm-based optimization proved to be useful for solving SMBR flux optimization problems.

• 한국잡초학회지
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• 제30권3호
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• pp.206-214
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• 2010

The laboratory and green house studies evaluated the effect of three different environmental factors on the seed germination, seedling emergence and survival of four major weed species in coconut plantations, Mimosa pudica, Ureana lobata, Panicum maximum and Pennisetum polystachyon. Germination percentage of all the weed species was significantly reduced with increasing soil moisture stress, no germination was observed at -0.9 MPa. Germination of both grass seeds ranged from 8% to 25% and 10% to 45% as moisture stress decreased from -0.4 MPa to 0 MPa, respectively. In contrast, seeds of M. pudica, and U. lobata were moderately tolerant to soil moisture stress and best adapted to moist environment. All the weed species seeds germinated over a wide range of soil pH values with the highest germination occurring at pH 6. In all the species, seedling emergence was declined rapidly with increasing depth with the exception of U. lobata. Seedling emergence significantly declined when the duration of flooding was three days or longer in dicotyledonous weed species and two days or longer in monocotyledonous weeds. This study illustrates the adaptability of these weeds to different environmental conditions which would enable the development of management strategies to reduce their populations below economic threshold levels in coconut plantations.