• Korean Journal of Weed Science
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• v.11 no.1
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• pp.50-59
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• 1991

Residual period and carry-over effect of some herbicides were determined using a bioassay method in six summer crops(potato, carrot, corn, water melon, soybean, and sesame). The effects were measured at regular time intervals after applying different rates of the herbicides. There were no great differences in residual period and carry-over injury between the soils and kinds of crops used. However, the residual period varied with the herbicides studied and the carry-over injury was dependent upon season and rate of the herbicide application, sampling depth of soil, and kind and seeding date of the test plant. When the residual herbicides were applied, the carry-over injury could be minimized by selecting tolernet crops, delaying seeding of the crops after application of the herbicides, and regulating the cultivation depth. Herbicides which showed no residual effect by the end of the cropping period(100-120 days for summer crops) and no carry-over effect were alachlor, trifluralin, ethalfluralin, metribuzin, and prometryn. When pendimethalin, metolachlor, linuron, methabenzthiazuron, and simazine were applied at the recommended rate or less, there was no carry -over injury at harvesting time. With doubling the recommended rate, however, the carry-over effect was found in sensitive crops. Napropamide applied at the rate of 300 g a.i./10 a brought about carry-over injury for Italian ryegrass and barley at 140 days in summer crops, whereas the injury was not found in Cruciferae (radish, Chinese cabbage). Nitralin applied at the rate of 150-300 g a.i./10a caused the carry-over injury for Italian ryegrass and barley at 140 days in summer crops. However, there was no injury for Cruciferae.

• Korean Journal of Remote Sensing
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• v.33 no.5_2
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• pp.631-640
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• 2017

The estimation of rice yield affects the income of farmers as well as the fields related to agriculture. Moreover, it has an important effect on the government's policy making including the control of supply demand and the price estimation. Thus, it is necessary to build the crop yield estimation model and from the past, many studies utilizing empirical statistical models or artificial neural network algorithms have been conducted through climatic and satellite data. Presently, scientists have achieved successful results with deep learning algorithms in the field of pattern recognition, computer vision, speech recognition, etc. Among deep learning algorithms, the SSAE (Stacked Sparse AutoEncoder) algorithm has been confirmed to be applicable in the field of forecasting through time series data and in this study, SSAE was utilized to estimate the rice yield in South Korea. The climatic and satellite data were used as the input variables and different types of input data were constructed according to the period of rice growth in South Korea. As a result, the combination of the satellite data from May to September and the climatic data using the 16 day average value showed the best performance with showing average annual %RMSE (percent Root Mean Square Error) and region %RMSE of 7.43% and 7.16% that the applicability of the SSAE algorithm could be proved in the field of rice yield estimation.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.1050-1056
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• 1999

The effect of ${\gamma}-irradiation$ was investigated on salted and fermented squid, squid jeotkal. Squid jeotkal was prepared with salt concentrations of 5%, 10% and 20% and was fermented at $15^{\circ}C$ and $25^{\circ}C$ after ${\gamma}-irradiation$ with doses of 0, 2.5, 5 and 10 kGy, respectively. Proximate composition, salinity, water activity (Aw), pH, total bacteria and sensory evaluation were examined during fermentation periods. Results showed that ${\gamma}-irradiation$ had no effect on proximate composition, salinity and Aw compared with non-irradiated squid jeotkal. However, pH and total bacteria, as well as sensory evaluation, were changed variously with processing conditions such as NaCl concentration, irradiation dose and fermentation temperature. The results of total bacteria and sensory evaluation showed that squid jeotkal with NaCl concentration of 10% and an irradiation dose of 10 kGy maintained high quality for 30 days at $15^{\circ}C$. Therefore, it was considered that ${\gamma}-irradiation$ was effective in processing low-salted squid jeotkal and extending its shelf-life without adding any food additives.

• Korean Journal of Agricultural Science
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• v.11 no.1
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• pp.85-93
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• 1984

This research was carried out to study the seed dormancy of radishes which were used for summer vegetation. The differences of dormancy of cultivars, maternal effects, the effect of full day length to mother plants, and the effects of chemical treatments for breaking the seed dormancy were considered for this study. These results sere summarized as follows; 1. The germination percentage of 7 cultlvars sown just after harvest were as follows;SP70-:0, PS11-:37.5, GJ75-:75.5, JD127-:77.5, YH85-:81.0, M55-:96.5, and JC73-:98.0%. 2. The dormany of $F_1$ seed of radish was severe when SP70-was used for mother plant. 3. Germination behavior was different by the maturity of plants grown for seed production. The dormancy of seed harvested from immature field-grown plants sown Nov. 10 was deeper than mature plants sown Mar. 22. 4. The germination ratio of tire seed of SP70-radish was increased by treatment of full day length to tire mother plant during full period of growing or since first flowering stage, while that was 0% by treatment since yellow ripening stage. 5. GA 200 ppm+thiourea 0.2% treatment was most effective for breaking of radish seed dormancy.

• Journal of Mushroom
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• v.13 no.3
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• pp.233-236
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• 2015

This report is the result of devising a method for utilizing the device of the load cell to maintain a constant water content of the medium every day to prepare a cultural substrates with the mixer for growing mushrooms bottle cultivation. A load cell was device under the medium mixer. It is developed when the device reaches the weight calculated as amount of substrate bottled and number of the bottle, it is automatically terminated by water injection. In addition, measuring the water content of each medium and the total weight of the medium reaches the target moisture content were calculated by using the program Cheong et al. (2015). Enter the total weight of the medium on the display unit of the load cell, when starting the water supply to reach the weight-based mixing media, the water supply is stopped. This method can improve the convenience by reducing the user's trouble in repeated work medium prepared by automating water supply. The suitable moisture content of the mixed medium for some kind of mushroom can be improved by the composition accuracy. And mycelial culture period, primordial period, mushroom growing period is maintained even of the medium can be produced stably. Therefore, it is possible to achieve a stable management of the mushroom farm according to mushroom quality and quantity stable throughout the year.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.1
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• pp.28-38
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• 2012

This study was conducted to investigate growth performance, photosynthesis, water use efficiency (WUE), and stomatal conductance ($g_s$) of container seedlings of Liriodendron tulipifera and Zelkova serrata growing under three different irrigation periods (1 time/1 day, 1 time/2 days and 1 time/3 days) for high seedling quality. The root collar diameter and height of L. tulipifera and Z. serrata seedlings were highest with 1 time/1 day irrigation, whereas they were lowest with 1 time/3 days irrigation. The two species showed low drought tolerance. As irrigation period was shortened, biomass and seedling quality index (SQI) of the two species increased. The ratio of height to root collar diameter (H/D) and the ratio of below to aboveground biomass (T/R) of the two species were lower with 1 time/3 days than at other irrigation periods. L. tulipifera and Z. serrata seedlings showed significantly higher photosynthetic capacity with 1 time/1 day irrigation. As irrigation period was shortened, $g_s$ of two species increased, while their WUE decreased significantly (P<0.05) These results show that 1 time/1 day irrigation provides the most optimal water condition for container seedling production of two species and irrigation controlling is very important for growth and quality of container seedlings.

• Asian Journal of Turfgrass Science
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• v.12 no.2
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• pp.113-126
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• 1998

Wear simulator로 답압이 가해진 크리핑 벤트그라스 (Agrostis palustris Huds.) 훼어웨이에서 관수방법·예지물 순환 및 질소시비수준의 여러 가지 잔디관리 요인이 엽조직 및 토양질소 함유량에 미치는 효과를 알아보기 위해 본 연구를 수행하였다. 연구포장은 'Penncross'크리핑 벤트그라스 반디밭으로 1988년에 sharpsburg silty-clay loam (Typic Argiudoll) 토양에 조성하였으며, 실험은 1989년부터 1991년까지 3년간 수행하였다. Split-split-plot 실험디자인을 사용하여 주구에 daily or biweekly irrigation, 세구에 clipping return or removal, 세세구에 low-N (5g), moderate-N (15g), high-N (25g N m-2 yr-1)처리를 난괴법 3 반복으로 배치하였다. 생육기간중 잔디예초는 12mm 예고로 일주일에 4번 실시하였고, 기타 잔디관리는 high maintenance 수준으로 유지되는 한지형 양잔디 훼어웨이 기준으로 실시하였다. 엽조직 및 토양샘플은 1989년 2회, 1990년과 1991년에는 3회씩 채취하여, 네브라스카 주립대 토양식물분석실에서 분석하였다. 답압이 가해진 크리핑 벤트그라스 훼어웨이 잔디에서 엽조직 질소함유량은 여러 가지 잔디관리 방법간 상호작용 효과가 관찰되었다. 1989년 나타난 질소시비수준과 관수방법간의 상호작용에서 daily irrigation 지역의 엽질소 함유량은 질소시비량이 low-N 수준에서 high-N 수준으로 증가함에 따라 3.51%에서 3.94%로 quadratic pattern으로 증가하였다. High-N 처리지역에서 엽질소 함유량은 daily irrigation 관수방법이 biweekly irrigation 관수방법보다 약 4% 정도 더 많은 것으로 나타났다. 엽질소 함유량은 특히 질소시비 수준에 따라 크게 영향을 받는 것으로 나타났다. 1990년 질소시비량이 low-N 수준에서 high-N 수준으로 증가함에 따라 3.50%에서 4.25%로 quadratic pattern으로 증가하였고, 1991년에는 4.20%에서 4.60%까지 linear pattern으로 증가하였다. High-N 처리구의 엽조직 질소함유량은 low-N 처리구와 비교시 1990년에는 21%, 1991년에는 10% 더 많은 것으로 나타났다. 잔디조성후 시간이 경과함에 따라 엽조직의 질소함유량도 증가하였다. Low-N 수준에서 1991년 엽질소 함유량은 1990년에 비해 20% 증가하였으며, high-N 수준에서는 1991년의 엽조직 질소함유량이 1990년 보다 8% 증가한 것으로 나타났다. 따라서, 잔디조성후 경과기간에 따라 연간 시비량을 조절할 필요가 있으며, 특히 새로 조성된 잔디밭과 조성된 지 어느 정도 지난 기존 잔디밭간에 차별화된 관리프로그램이 필요한 것으로 판단되었다. 잔디관리에서 답압이 가중되는 정도에 따라 지역별로 장기간 차별화된 관리 접근을 해야하고, 정기적으로 토양 및 엽분석을 실시해서 시비프로그램에 활용하는 것이 필요하다 하겠다. 본 연구결과 나타난 잔디관리 요인간 상호작용효과는 잔디관리시 여러 가지 관리방법에 따른 효과를 입체적으로 분석해서 해당 골프장 현실에 적합한 통합적인 잔디관리(integrated turfgrass management)의 필요성을 제시한다고 할 수 있겠으며, 또한 답압가중 정도에 따른 잔디관리요인간의 반응효과차이는 향후 무답압 지역에서 실시된 연구결과를 답압을 받고 있는 경기장 및 골프장 등의 잔디밭에 적용할 경우에는 주의깊게 데이터 활용을 해야 되리라고 사료되었다.

• FLOWER RESEARCH JOURNAL
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• v.19 no.1
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• pp.22-29
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• 2011

The experiment investigated effect of duration, temperature, and light condition during chilling treatment on growth and flowering of four Campanula species in a factorial experiment. Two parent species, Campanula punctata Lam. var. rubriflora Mak. and C. Punctata Lam., and their two $F_1$ hybrids, C. punctata Lam. ${\times}$ C. punctata Lam. var. rubriflora Mak. ('Jiknyeo') and C. punctata Lam. var. rubriflora Mak. ${\times}$ C. punctata Lam. ('Gyeonu'), were used. Plants were cultured in vitro for five weeks at $25^{\circ}C$ under about $75{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD before being chilled at 4 or $25^{\circ}C$ for 3, 6, or 9 weeks under a darkened or lighted (about $10{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD) condition. After chilling treatment, plants were transplanted to 10 cm pots filled with a commercial growing medium and were transferred to environment-controlled growth chambers and subsequently to a greenhouse to observe their reproductive growth. Growth of all species and flowering of a $F_1$ hybrid 'Jiknyeo' were affected by duration, temperature, and light condition during chilling treatment. The greatest growth and survival percentage were observed in C. punctata Lam. var. rubriflora Mak. The survival percentage was greater when plants were chilled in a lighted than darkened condition, whereas it decreased when plants were chilled more than six weeks in vitro. Among the four species tested, flowering was observed only in a $F_1$ hybrid 'Jiknyeo' with 62.5% flowering plants when it was chilled at $25^{\circ}C$ for three weeks under a lighted condition. Percent flowering plant was affected by duration, temperature, and light condition during chilling treatment. Three-week chilling at $4^{\circ}C$ under a darkened condition significantly reduced days to flowering. These results suggest that the low temperature requirement for flowering is not qualitative but quantitative in Campanula species. Further experiment with more number of plants is necessary to ascertain this conclusion.

• Journal of Bio-Environment Control
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• v.23 no.2
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• pp.139-143
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• 2014

This study was conducted to investigate the effect of cultivation period and rockwool block size on the growth and early yield of paprika transplants grown in a closed transplant production system. Paprika seeds were sown and germinated in three different size of rockwool blocks ($45{\times}40{\times}35$, $70{\times}70{\times}60$, $100{\times}100{\times}65mm$) and cultivated in a closed transplant production system for 23, 30, and 37 days after sowing. Paprika transplants were cultivated using $100{\times}100{\times}65mm$ rockwool blocks in a greenhouse following a conventional and typical production method for comparing with the growth of paprika transplants grown in a closed transplant production system. Also, we transplanted paprika transplants grown for 23, 30, and 37 days in a closed transplant production system and greenhouse to rockwool slabs and investigated fresh weight of fruits and yield 125 days after sowing. The growth of paprika transplants grown in $70{\times}70{\times}60mm$ rockwool blocks in a closed transplant production system was highest, and the quality of paprika transplant grown in a closed transplant production system was better than in a greenhouse. Rockwool block size and cultivation period in a closed transplant production system did not affect fresh weight of fruits, however, yield was largest when paprika transplants were cultivated using $70{\times}70{\times}60$ and $100{\times}100{\times}65mm$ rockwool blocks for 23 days in a closed transplant production system. These results suggest that decreasing rockwool block size and cultivation period can be strategically used to enhance transplant quality and yield of paprika, as paprika transplants were cultivated in a closed transplant production system.

• Journal of Bio-Environment Control
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• v.24 no.2
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• pp.128-133
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• 2015

Mushrooms can grow in nature when adequate temperature and humidity are maintained, but such condition can be satisfied for only a short period of time on an annual continuum. Therefore, it can be deemed that a majority of the distributed mushrooms in the current market are produced in an artificially manipulated environment. This study was conducted to resolve the problem of the Oyster mushroom cultivation house's internal temperature and humidity imbalance, where the Oyster mushrooms are cultivated in a multi-layered shelves. The air circulation fans were installed to improve the air uniformity of the Oyster mushroom cultivation house by using multi-layered shelves. During the experiment, the ambient temperature and the ambient relative humidity ranged from $5.2^{\circ}C$ to $20.4^{\circ}C$ and 40% to 100% respectively. Due to the change of the outdoor temperature, the internal temperature of the Oyster mushroom cultivation house also changed, ranging from $13.3^{\circ}C$ to $18.4^{\circ}C$, but the temperature gap between the different internal location of the facility during the conforming recorded time only ranged from $0.2^{\circ}C$ to $1.3^{\circ}C$, being significantly stable. The internal relative humidity, ranging from 82% to 96%, also changed due to the change of the outdoor temperature. Nevertheless, the relative humidity gap between the different internal location during the conforming recorded time only ranged from 2% to 7%. Furthermore, the research staff were able to maintain the concentration of $CO_2$ from 575ppm to 731ppm(below 1,000ppm was the goal) indicating the possibility of an even management of the internal environment by installing the air circulation fan.