• 한국작물학회:학술대회논문집
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• 한국작물학회 1988년도 춘계 학술대회지
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• pp.104-105
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• 1988

• 한국작물학회:학술대회논문집
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• 한국작물학회 2006년도 한국약용작물학회 공동춘계학술발표회
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• pp.204-205
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• 2006

• 한국작물학회:학술대회논문집
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• 한국작물학회 2007년도 6th OSONG INTERNATIONAL BIO-SYMPOSIUM
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• pp.203.1-203.1
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• 2007

• Journal of Biosystems Engineering
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• 제14권1호
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• pp.8-15
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• 1989

Agricultural materials do not react in a purely elastic manner, and their responses when subjected to stress and strain are appeared from a combination of elastic and viscous behavior. Various researchers have studied the mechanical and rheological properties of the many agricultural materials, but those properties are available mostly foreign varieties of agricultural products. Rheological properties of rice seedlings become important to formulate the principles governing their mechanical behavior. The objectives of this study were to experimentally determine the stress relaxation properties of rice seedlings such as three Japonica-type and one Indica ${\times}$ Japonica hybrid in the transplanting age. The results of this study are summarized as follows; 1. The stress relaxation behavior could be described by the generalized Maxwell model. 2. The phenomenon of stress relaxation happened abruptly just after loading and this phenomenon weakened with the loading time lapsed. 3. With increase of the initial stress, the stress relaxation intensity and residual stress increased, while the relaxation time was constant with increased, while the relaxation time was constant with increase of the level of initial stress. 4. With increase of loading rate, the stress relaxation intensity increased, while the relaxation time and residual stress decreased.

• 한국잡초학회지
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• 제18권2호
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• pp.136-145
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• 1998

잔디밭에서 문제잡초로 알려져 있는 향부자의 효과적인 방제를 위한 기초 자료를 제공하고자 향부자의 생육특성, 생장조절제 처리가 맹아 및 생육에 미치는 영향, 제초제의 선발실험, 향부자의 일반성분을 조사하였다. 향부자의 개화는 이식 시기에 관계없이 이식 30일부터 시작되었고 괴경은 기온이 $10^{\circ}C$이하로 내려가면서 형성되기 시작하였다. 생장조절제 BA, ABA, TS-303, PDJ 등의 4종을 향부자 괴경에 처리한 결과 맹아에는 영향을 미치지 않았으며, 이식 60일째부터 경엽에 4회 처리시 4종 공히 신초 수와 지하부 건물중을 다소 증가시켰으나 신초 건물중과 괴경 수에는 영향을 미치지 않았다. Imazaquin 30g ai/10a 처리는 괴경으로부터 다량(multi-shooting)의 신초를 발생시켰으나 pyrazosulfuron-ethyl과 bensulfuron-methyl 처리는 multi-shooting 현상을 보이지 않았다. Pyrazosulfuron-ethyl 10g ai/10a 처리는 향부자의 생육을 90% 가까이 억제하여 bensulfuron-methyl 10g ai/10a 보다 높은 방제율을 보였다. 향부자 성숙한 괴경의 구성성분은 수분 61.83%, 탄수화물 31.60%, 조단백질 4.03%, 조지방 1.57%, 조회분 0.97% 이었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2005년도 추계학술발표회 요지
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• pp.128-129
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• 2005

• 한국작물학회지
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• 제64권3호
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• pp.213-224
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• 2019

There is an increasing frequency in the occurrence of abnormal weather phenomena such as sharp increases and decreases in temperature. Under these weather conditions, the heading time of rice changes unexpectedly, which poses problems in agriculture. Therefore, we investigated the effect of temperature on the heading response at different growth stages in rice. During the period from transplanting to heading, the plants were subjected to different temperature treatments, each for a 9-day period, to observe the heading response. For the heading date analysis, "heading date" was defined as the number of days from transplanting to the appearance of the first spikelet. We found that the influence of temperature increased in the order of rooting stage, followed by meiosis, early tillering, spikelet differentiation, and panicle initiation stage in all ecological types and cultivars. In particular, unlike the results reported previously, the effect of temperature on heading during the photo-sensitive period was very small. Meanwhile, the influence of temperature on vegetative growth response at different growth stages was not consistent with heading response. These results can be used as basic data for predicting the variation in heading date owing to temperature variation at each growth stage. In addition, we propose that the concept of day length should be included in determining the influence of temperature on the photo-sensitive period.

• 한국토양비료학회지
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• 제6권3호
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• pp.165-172
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• 1973

전분석(全分析) 의(依)한 포장재배(圃場裁倍) 수도(水稻)의 영양진단(營養診斷) 적기(適期)와 생육시기별(生育時期別) 양분농도(養分濃度)와 생산량과의 관계는 다음과 같다. 1. 결비구(缺肥區)에서 최저농도(最低濃度) 발현빈도(發現頻度)는 질소(窒素)에서 이앙후(移秧後)20일(日)(20>최분기(最分期)(MT)>수확기고(收穫期藁)(HS)>유수형성기(幼穗形成期)(EF)>출수기고(出穗期藁)(FS)>수확기곡실(收穫期穀實)(HG)>출수기수(出穗期穗)(FE)의 순(順)이고 인산(燐酸)에서 MT>EF>HS>20=FS>FE>HG의 순(順)이며 가리(加里)에서 MT>EF>20>FS>HS>HG>FE의 순(順)이었다. 2. 결비구(缺肥區)에서 그 양분(養分)의 최저농도(最低濃度) 발현빈도(發現頻度)가 가장 높은 시기(時期)가 근권영양진단(根圈營養診斷)의 최적시기(最適時期)일것이며 그 시기(時期)는 N에서 이앙후(移秧後) 20일(日) P와 K에서 최고분(最高分)얼기(期)로 나타났다. 3. 최고농도(最高濃度)와 최저농도(最低濃度)의 상대차이(相對差異)($100{\times}(L-H)/H$)가 가장 큰것은 N와 P는 수확기(收穫期) 고(藁)에서이고 K와 Si는 수확기곡실(收穫期穀實)에서 이며 이들 양분(養分)의 수(穗)로의 전이율(轉移率)과 관련(關聯)되는것 같다. 4. N는 모든 시기(時期)에 P는 최분기(最分期)와 유수기(幼穗期) 이외(以外)의 모든 시기(時期)에 K는 이앙후(移秧後) 20일(日)과 수확기(收穫期)에 최고농도구(最高濃度區)의 수량(收量)이 최저농도구(最低濃度區)의 수량(收量)보다 크나 Si는 언제나 적어서 양분농도(養分濃度)와 수량(收量)과의 밀접도(密接度)는 N>P>K>Si의 순(順)으로 볼 수 있다. 5. 최저농도구(最低濃度區)의 수량(收量)과 최고농도구(最高濃度區)의 수량상대차이(收量相對差異)($100{\times}(L-H)/H$)가 가장 큰 시기(時期)는 N. P. K 모두 이앙후(移秧後) 20일(日)로 수량(收量)과 양분농도간(養分濃度間)에 가장 밀접(密接)한 시기(時期)로 나타났다. 6. 최고수량(最高收量)과 최저수량구(最低收量區)의 N. P. K. 농도(濃度) 차이(差異)(H-L)는 이앙후(移秧後) 20일(日)에서 가장 크다. 최고건물(最高乾物) 생산구의 N. P. K. 농도(濃度)가 최고수량구(最高收量區)의 그것보다 낮은것도 이때이다. 이러한 사실은 농도(濃度)와 수량간(收量間)에 가장 밀접(密接)한 시기(時期)임을 뒤받침한다. 7. 최고농도구(最高濃度區)의 수량중(收量中)에서 최고수량(最高收量)을 보인 것은 N. P. K 모두 이앙후(移秧後) 20일(日)이며 최저농도구(最低濃度區)의 수량중(收量中)에서 최저수량(最低收量)은 질소(窒素)에서만 이시기에 온다. 8. 이하(以上)의 사실에서 근균영양진단(根圈營養診斷)의 최적시기(最適時期)는 수량(收量)과 관련(關聯)된 영양진단(營養診斷)의 시기(時期)와 다른 것을 알 수 있다.

• 산업경영시스템학회지
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• 제25권2호
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• pp.35-41
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• 2002

This paper describes an automatic transplantation machine of optical fiber controlled by PLC. The transplantation operations is a key operation for the optical fiber application products, such as bag, cap, and others. To transplant 200∼500 optical fibers, there are many recurrent manual operation needed with conventional process. In this paper. we propose an automatic machine that reduce transplanting time and enhance product quality. Developed machine includes transplantation, heat cutting and ultraviolet coating operation. Also proposed Machine is controlled by PLC to adjust operation parameters such as pulling length, cycle time, coating time and others. Developed Machine has been applied in the field and found to be a useful system.

• 한국농공학회지
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• 제21권3호
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• pp.83-91
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• 1979

This study was conducted in order to find out the performance of rice transplanters in accordance with the change of the trans-planting days after pudding and the water depth flooding the paddy field at the time of transplanting : and thus to select the optimum paddy field preparation procedures for an efficient utilization of rice transplanters. The performance factors of the two different types of rice transplanters were measured during the first 6 consecutive days after puddling and with 3 different levels of water depth flooding the paddy fields. The results of this study were analysed and summarized as follows : 1. Wheel sinkage decreased very rapidly from 0 to 2 days after puddling and slowly from 3 to 5 days after puddling. 2. The depth of the test cone penetration decreased rapidly during the first few days after puddling. It was 17.8cm just after puddling, and decreased to 13.4cm one day after puddling. After 2 days, the rate of decrease was dampened, and after 5 days it kept constant value of 9.2cm. 3. Two days after puddling, the hill interval was 15.8cm (98.75% of the preset value) for broadcasted seedling rice transplanter with 3cm flooding depth : This value was the closest to the pre-adjusted value of 16cm. The general performance of broadcasted-seedling type rice transplanter was better than that of strip-seedling type rice transplanter. 4. Usually the working performance of a rice transplanter is evaluated with uniformity and adjustability of the hill intervals. The hill interval was the most uniform and closest to the pre-set value of 16cm when planted two days after puddling with 3cm of water depth. When it was inavoidable to plant 4 days after puddling with stripseedling type rice transplanter, it is advisable to let the water flooded somewhat deeper. 5. The percentage of missing hills including floating and burried seedlings was the highest just after puddling and ie decreased substancially until 3 days after puddling and then it increased again. Hence, the optimal time transplanting is to be between 2 and 3 days after puddling. 6. Better postures of planted seedlings were found when planter 2 days after puddling than 3 days after puddling. Six cm of flooding water depth always gave the best results with respect to the postures of planted seedlings. Broadcasted-seedling rice transplanter, in general, showed better posture of planted seedlings than did strip-seedling type rice transplanter. 7. Judging from the above results, the optimal conditions will be 3cm of flooding depth and transplanting between 2 and 3 days after puddling.