• 한국작물학회지
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• 제62권3호
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• pp.233-240
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• 2017

간척지 토양에 수수 재배기술체계 확립을 위해 토양염농도 $1.6dS\;m^{-1}$와 $3.2dS\;m^{-1}$에서 파종시기와 재식거리를 달리하여 시험한 결과는 아래와 같다. 1. 파종깊이별 입모율은 남풍수수, 황금찰수수 모두 3cm 깊이에 파종했을 때 높은 입모율을 나타내 수수 파종 깊이는 3 cm깊이로 파종하는 것이 적합할 것으로 판단된다. 2. 토양수분함량별 입모율은 10~30 kpa ~ 51~70 kpa까지 차이가 없었으며, 파종 전 종자를 물에 침지하여 수분을 흡습시켜 파종한 효과는 인정되지 않았다. 3. 토양염농도별 입모율은 남풍찰수수는 $1.6dS\;m^{-1}$ 농도까지는 무염과 동일한 입모율을 나타냈으나, 황금찰수수는 $1.6dS\;m^{-1}$에서부터 감소가 시작되었다. 4. 포장시험에서 품종별 입모율은 남풍찰수수가 황금찰수수보다 높았고, 파종시기에 따른 초장과 $m^2$당 이삭 수는 파종시기가 빨랐을 때 크고 많은 경향이었으며, 재배토양 염농도의 증가는 초장, 지상부 건물무게, 이삭무게를 감소시켰다. 5. 수량은 토양염농도에 관계없이 6월15일, 6월25일 모두 남풍찰수수가 높았고, 토양염농도 증가에 따른 품종별 감수율은 6월15일 파종에서는 남풍찰수수가 적었으나 6월25일 파종에서는 황금찰수수가 적었다.

• Journal of Biosystems Engineering
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• 제23권3호
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• pp.271-276
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• 1998

A gripper mechanical design using a pneumatic system was developed to successfully grip, hold, and release a seedling plug for transplanting it. The gripper comprised of two air cylinders and shovel-type fingers. The gripper can grasp and hold a seedling by sliding the two fingers attached to the two separate air-cylinders, mounted at an angle of 15$^{\circ}$ When releasing a plug, retraction of the fingers gives a seedling little attachment to the gripper. To prevent seedling from attaching to the fingers, press-plates were attached to the end of the gipper. Transplanting performance of the developed gripper was tested with cucumber seedlings at different soil moisture contents. Overall transplanting performance of developed gipper was higher than the performance of the previously developed gripper. Best transplanting result was achieved at medium level of soil moisture content.

• 생물환경조절학회지
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• 제6권4호
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• pp.258-263
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• 1997

정식기에 의한 플러그묘 정식시 최적활착을 나타내는 관수량, 진압상태 등을 구명하여 관련정식기 개발과 최적 생육관리를 위한 기초자료를 획득하고자 기초시험과 포장실험을 실시한 결과를 요약하면 다음과 같다. 1. 작물별 정식 성공률은 정식호퍼 크기별로는 유의성이 없으며, 작물의 초장과 관련이 크며, 반자동 정식기의 최대 정식가능초장은 30cm, 최적초장은 28cm 이내로 조사되었으며, 고추와 배추 공히 정식시 관수 작업을 실시하려면 큰 규격의 호퍼가 적당할 것으로 판단되었다. 2. 정식 후 10일이 지난 상태에서 플러그묘의 생존율은 토양수분에 의한 영향이 크며, 고추의 경우 15%이상의 토양수분에서는 98%이상의 생존율을 보였고, 배추의 경우 16% 이상의 토양수분에서는 96% 이상의 생존율을 나타내었다. 그러나 고추와 배추를 심은 토양이 거의 완전 건조한 상태인 3.8%, 3.1% 각각의 토양수분에 대하여 15%와 14%의 생존율을 나타내었다. 따라서 토양수분 18% 이상에서는 정식시 관수가 필요 없고, 13%에서는 50cc 이상 관수가 필요하며, 토양의 수분이 3.8%이하일 때는 100cc 이상 초기관수 후 3일 내에 재관수가 필요할 것으로 판단되었다. 3. 좌우진압, 전후좌우진압의 생존율 차이는 없었으므로 현재의 반자동정식기 진압방식(좌우진압)의 개선은 필요하지 않았다.

• 한국작물학회지
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• 제46권4호
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• pp.289-295
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• 2001

Experiments were conducted to find out the optimum level of slow release N fertilizers when total amounts of nitrogen required throughout the growing season in paddy were applied in the soil of seedling box. To evaluate the emergence rate and growth of rice seedlings, five levels of Meister (MS) 10, MS S10, and latex coated urea (LCU) which are equivalent to 0, 40, 60, 80, and 100kg N h $a^{-l}$ were mixed in soil of the seedling box. Emergence rate differed depending on the fertilizers and N levels; in MS 10 plots the emergence rate was 40.8% at 40kg N h $a^{-l}$ and no seedlings were emerged at the higher levels, in MS S10 plots higher than 80% at all the N levels, and decreased with the N levels from 70.0% at 40 kg N h $a^{-l}$ to 59.5% at 100kg N h $a^{-l}$ of LCU. Seedling started to wilt at 40 kg N h $a^{-l}$ of MS 10 and 80 and 100 kg N h $a^{-l}$ N of LCU on the 8th day after sowing, while seedling growth was normal at all the levels of MS S10. Field performance of rice was evaluated at the 0, 30, 60, 90, 120kg N h $a^{-l}$ of MS S10 applied in the soil of seedling box and N was not applied in paddy. Grain yield at 90 and 120kg N h $a^{-l}$ of MS S10 was similar to conventional urea split application (120 kg N h $a^{-l}$), but significantly higher compared to 30 and 60kg N h $a^{-l}$ of MS S10. Fertilizer N recovery decreased with N levels and the N recovery at 90 kg N h $a^{-l}$ of MS S10 and conventional urea split application were 62.2 % and 44.2%, respectively, with similar grain yield. The optimum level of MS S10 to be applied in seedling box seems to be about 90 kg N h $a^{-l}$ considering grain yield, price of fertilizer, labor applying fertilizer, and fertilizer N recovery.d fertilizer N recovery.

• 임산에너지
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• 제20권1호
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• pp.1-5
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• 2001

국내 주요 간벌목과 목질재료 탄화물 중 성능면과 자원면을 고려하여 선정한 수 토양개량시험을 실시하여, 이들 목질폐잔재 탄화물들이 토양개량제로서의 효과와 토양개량과 관련하여 입자크기에 따른 효과에 관하여 조사한 결과는 다음과 같다. 서양측백 파종실험에서 토양에 목탄을 처리한 것이 무처리구보다 좋은 성장을 나타냈으며 그 중 흡착성이 좋은 잣나무탄이 가장 좋은 처리효과를 나타냈다. 칠엽수 이식실험에서도 무처리보다 목탄을 처리한 것이 좋은 길이성장을 보였다. 또한 파종 및 이식실험에서 입자의 크기에 따른 성장량의 차이는 없는 것으로 나타났다. 사과나무 문우병에 의한 뿌리썩음 때문에 쇠약해진 사과나무에 목탄을 시용하여 수세회복의 효과를 얻었다.

• Journal of Ecology and Environment
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• 제42권1호
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• pp.43-49
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• 2018

Iris laevigata is geographically restricted and legally protected in Korea. In this study, a mesocosm study was conducted to examine the effects of environmental conditions such as water levels and soil nutrient conditions on the growth and survival of I. laevigata seedlings. Complete submergence lowered the total number of leaves, biomass, and survival rates. A rise in soil nutrients increased overall seedling growth and increased tiller numbers via the promotion of asexual reproduction. Also, we found that the lowest measured values of seedlings are associated with the most stressful condition due to the interaction of low soil nutrients and high water levels. I. laevigata seedlings, however, are distributed in low-nutrient habitats such as floating mat, even though they do not grow well under these conditions. This study suggests that I. laevigata does not prefer low-nutrient condition but choose another benefit such as low competition. Also, the water level must be lower than the seedling height for effective growth and management of I. laevigata.

• Journal of Biosystems Engineering
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• 제4권1호
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• pp.48-57
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• 1979

In order to obtain a standard reference for designing an adequate power rice transplanter, the cutting forces depending upon variety of seedling, sowing density, seedling age and soil moisture content of mat-type seedling were measured by the rice transplanter installed with force measuring device of dynamic strain gage system in the laboratory. The result of this study are summarized as follows : 1. Cutting velocity and acceleration transplanting hoe obtained from jinematic analysis of planting mechanism was 1.32m/sec and 81.5m/$sec^2$ when planting crank-shaft rpm was 160. 2. Little difference between cutting forces on 30-days old seelings of japonica and Indica type was observed, as the cutting forces determined were 2.0kg per hill for Japonica type and 2.1kg per hill for Indica type. 3. Cutting forces determined on 40-days old seedlings were 2.5kg, 2.3kg, 3.1kg and 2.9kg per hill for Milyang No.15, Tongil, Akibare and Milyang No.23 compared to the other varieties. 4. The cutting force was not greatly affected by the sowing densities , only five percent of differences were observed epending upon the sowing densities. 5. Cutting forces were 2.7kg and 2.0kg per hill on 40-days old seedlings and 30-days old seedlings respectively. About 38 percent of more forces was required in cutting 40-days old seedling than in cutting 30-days old seedlings. 6. More cutting forces were required as soil moisture content of mat-type seedling was decreased. 7. Root length after cutting by the planting hoe and their relationships with soil moisture content on 30-days old seedlings, are as follows ; $y=4.147-11.384x+ 28.854x^2$ where , $y$=root length after cutting. (cm) , $x$=soil ture content of mat type seedlings.(%, d.b.) 8. Cutting forces were varied with the width of cuttings ; those on 40-days old mat type seedlings were 2.7kg and 2.2kg per hill when cutting with 14 mm and 10mm of width respectively, about 32 percent of more forces was required when cuting with 14mm of width compared to 10mm of width.

• 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.

• 한국토양비료학회지
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• 제17권1호
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• pp.24-29
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• 1984

왕겨부초와 피트시용한 묘포(苗圃)에서 묘삼수량(苗蔘收量)은 토양수분(土壤水分)에 의존(依存)하였으며 이 의존도는 토양칼리가 감소할수록 증가하였다. 부초와 피트처리는 토양수분을 증대시켰다. 수량의 토양수분 의존도에 대한 칼리의 영향은 일정수분 범위에서 일정할 것으로 보이며 이 수분범위는 묘삼생육의 적정수분 범위일 것 같다. 수량과 토양수분의 편상관계수 유기물, Mg, Ca에 관하여 유의성이 있었다. 수량에 관한 최적 다중(多重)회귀는 수분, K, Ca,의 조합이었다. 토양유효인산은 부초에 의하여 증가되고 피트 저수준에서 증가되나 고수준에서 감소되었다. 토양수분, pH, Ca, Mg, K, OM의 두 요인 간에는 K와 수분 또는 pH관계를 제외하고 직선유의상관이 있었다. 암모니아태질소는 Mg와 부 상관이었다. 질산태질소와 K 또는 $NH_4-N$간에 그리고 P와 K+Ca+Mg간에 2차회귀관계가 있었다. 토양요인 간에는 직선관계보다 2차회귀관계가 유의성이 컸다. 부초는 경장을 증가시켰으며 엽면적지수는 1.06~1.67범위였고 묘당엽 면적은 $16.0cm^2{\sim}18.8cm^2$범위였다.

• Journal of Biosystems Engineering
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• 제24권1호
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• pp.51-58
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• 1999

A color image processing algorithm was developed to assist the robotic plug-seedling transplanter. The algorithm was designed to identify and locate empty cells in the seedling tray. The image of pepper seedling tray was segmented into regions of plant, frame and soil using thresholding technique which utilized HSI or RGB color characteristics of each region. The detection algorithm was able to successfully identify empty cells and locate their two-dimensional location. The overall success rate of the algorithm was about 88%.