• 한국잡초학회지
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• 제9권3호
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• pp.238-244
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• 1989

신규(新規) 제초제(除草劑)에 dithiopyr의 제초효과(除草效果) 변화(變化)에 미치는 각종(各種) 재배(栽培) 화경조건(環境條件)의 영향(影響)에 대하여 조사(調査)한 바 다음과 같은 결과(結果)를 얻었다. Dithiopyr는 추천약량(推薦藥量)의 1/3수준(水準)인 0.04kg a.i./ha 약량(藥量)에서도 피, 물달개비 등에 대하여 89.3% 이상의 효과(效果)가 있었고, 0.08kg a.i./ha 약량(藥量) 이상부터는 100%의 방제율(防除率)을 보였다. 제초효과(除草效果)는 토성(土性), 누수량(漏水量), 온도(溫度), 담수심(湛水深), 관수시간(換水時間)의 차이(差異)에 따른 영향을 거의 받지 않았다. 제초효과(除草效果)는 이앙전(移秧前) 처리(處理) 혹은 이앙(移秧) 후(後) 12일 이상(以上)의 처리(處理)보다는 5-8일 처리(處理)가 높았다.

• 한국약용작물학회지
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• 제24권3호
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• pp.183-190
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• 2016

Background: This study determined the effects of mulching, an environment friendly organic cultivation method, on antioxidant compound contents and growth in Codonopsis lanceolata, commonly known as Deodeok. Methods and Results: C. lanceolata was treated by mulching with several different methods (a non-woven fabric, biodegradable film, or rice husks) and also treated with hand weeding. A non-treatment plot was used as a control. The growth and levels of weed control in C. lanceolata were better in plants cultivated under mulching treatments (non-woven fabric, biodegradable film, and rice husks) than in those under non-mulching treatments (hand weeding and non-treatment). The contents of antioxidant compounds, such as total flavonoids, phenolics, and anthocyanins, were highest under the biodegradable film treatment, followed by the non-woven fabric treatment, rice husks treatment hand weeding, and non-treatment. There were identifiable differences in DPPH and ABTS activity in comparison to antioxidant compound content by solvent fractions. Mulching treatments resulted in higher DPPH scavenging activity in water and ethyl ether fractions and ABTS scavenging activity in n-butanol fractions than in other fractions, as opposed to hand weeding and non-treatment groups, although total activity of DPPH and ABTS did not increase with mulching treatments. Conclusions: Mulching C. lanceolata with biodegradable film and non-woven fabric is an effective method for improving plant growth and inhibiting the occurrence of weeds as well as for increasing antioxidant compound content and altering antioxidant activity.

• Journal of Biosystems Engineering
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• 제41권4호
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• pp.294-303
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• 2016

Purpose: This study aimed to evaluate the profitability of four selective mechanization systems in rice cultivation. Methods: Field experiments were conducted in the farmers' field during the wet season (June to November) of 2015 in Bangladesh. Mechanization systems were applied to evaluate four different selective levels (treatment) in eleven consequent operations. Seedlings were raised in a traditional seedbed and trays for manual and mechanical transplanting, respectively. Land preparation, irrigation, fertilizer, pesticide, carrying, and threshing and cleaning operations were performed using the same method in all the experimental plots. The mechanical options in the transplanting, weeding, and harvesting operations were changed. The mechanization systems were $S_1$ = hand transplanting + hand weeding + harvesting by sickle, $S_2$ = mechanical transplanting + Bangladesh Rice Research Institute (BRRI) weeder + reaper, $S_3$ = mechanical transplanting + BRRI power weeder + reaper, and $S_4$ = mechanical transplanting + herbicide + reaper. This experiment was performed in a randomized complete block design with four replications. Power tiller, rice transplanter, BRRI weeder, BRRI power weeder, self-propelled reaper, BRRI open drum thresher, and BRRI winnower were used in the respective operations. Accordingly, the techno-economic performances of the different technologies were calculated and compared with those of the traditional system. Results: The mechanically transplanted plot produced 6-10% more yield than the hand transplanted plot because of the use of tender-aged seedlings. Mechanical transplanting reduced 61% labor and 18% cost compared to manual transplanting. The BRRI weeder, BRRI power weeder, and herbicide application reduced 74, 91, and 98% labor, respectively. The latter also saved 72, 63, and 82% cost, respectively, compared to hand weeding. Herbicide application reduced the substantial amount of labor and cost in the weeding operation. Mechanical harvesting also saved 96% labor and 72% cost compared to the traditional method of harvesting using sickle. Selective mechanization saved 15-17% input cost compared to the traditional method of rice cultivation. Conclusions: Mechanical transplanting with the safe use of herbicide and harvesting by reaper is the most cost- and labor-saving operation. The method might be the recommended set of selective mechanization for enhancing productivity.

• 한국비블리아학회지
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• 제22권2호
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• pp.249-278
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• 2011

본 연구는 대학도서관의 효과적인 장서폐기를 위한 개선방안을 제안하는데 그 목적이 있다. 이를 위하여 국외 대학도서관의 장서폐기지침과 장서폐기사례를 살펴보고, 장서폐기를 실시한 경험이 있는 국내 대학도서관을 대상으로 현재 시행되고 있는 장서폐기 운영현황과 지침현황을 알아본 후에 이들 내용을 토대로 그 문제점을 분석하고 대학도서관 장서폐기의 개선방안을 제안하였다.

• 한국정밀공학회지
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• 제31권1호
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• pp.43-50
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• 2014

This paper introduces a robot platform which can do weeding while traveling between rice seedlings stably against irregular land surface of a paddy field. Also, an autonomous navigation technique that can track on stable state without any damage of the seedlings in the working area is proposed. Detection of the rice seedlings and avoidance knocking down by the robot platform is achieved by the sensor fusion of a laser range finder (LRF) and an inertial measurement unit (IMU). These sensors are also used to control navigating direction of the robot to keep going along the column of rice seedling consistently. Deviation of the robot direction from the rice column that is sensed by the LRF is fed back to a proportional and derivative controller to obtain stable adjustment of navigating direction and get proper returning speed of the robot to the rice column.

• 한국비블리아학회지
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• 제4권1호
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• pp.103-127
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• 1980

Due to the rapid growth of publications, librarians have been facing the problems caused by the shortage of stack as well as the quality deterioration of library collections. This naturally disappointed the user communities and the present library activities are weak and inadequate. It seems to the author that one of the desirable actions in remedying this problems is to weed library collections properly and regulraly. The purpose of this study is to establish weeding criteria in library collections, particulary in the fields of polictical science, economics and law In order to establish weeding criteria, shelf-time period which is the length of time that a book remains on the shelf between the last two users of a volume, was measured by examining the book cards or date-due slips of circulating books and collections which remained in the stack. The results of this study are as follows: (1) In the fields of political science economics and law, the shelf-time periods of general materials in Korean for circulation was measured. (2) This study shows shelf-time periods that vary in different subject fields. (3) Combining the shelf-time periods of books in active circulation and the total collection including books which have never been circulated, the size of library holdings which may satisfy a certain percentage of the current circulation can be estimated.

• 정보관리연구
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• 제28권1호
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• pp.62-89
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• 1997

본 연구의 목적은, (1) 과학기술문헌정보 중 원자력분야 문헌정보의 인용분석을 통하여 정보자료의 수명 측정과, (2) 한국원자력연구소의 실제 폐기데이터의 평균수명을 측정하고, (3) 인용문헌의 실제이용율에 대한 예측과 문제를 보완하기 위하여 동연구소에서 1992년 1994년 까지의 이용(대출)통계 분석을 통한 정보자료이용의 수명을 측정하였다. 그리하여 이들 결과에 입각한 장서폐기 모형을 설계함으로써 점차 문제로 대두되고 있는 과학기술분야 정보자료의 폐기에 대한 효과적이고 합리적인 폐기기준을 모색하였다.

• 한국지형학회지
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• 제23권2호
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• pp.61-70
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• 2016

This study intended to analyze the spatial distribution of two types of weeding song (Short Bang-a and Sangsa ryu) and how geomorphic elements influence the propagation of the songs in Chungcheongbuk-do area. The distribution of the two types of song was mapped as point data. According to the result, both types showed similar distribution pattern. In order to figure out the reason of this similarity, the distribution pattern of songs was analyzed at various scales based on geomorphic elements including river, mountain and lineament. The result showed that most of distribution pattern of songs followed the lineament direction. Also, the spatial continuity among mountain that was formed by large and small lineament in various directions could be the path of the cultural diffusion. If the lineament with same direction does not intersect other lineament that have different direction, spatial continuity would be blocked. Consequently it was confirmed that propagation of songs has not spread smoothly.

• 한국잡초학회지
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• 제7권3호
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• pp.329-336
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• 1987

Glyphosate의 수종(數種) 제초제간(除草劑間)의 혼용(混用)에 따른 상호작용(相互作用)을 검토(檢討)할 목적(目的)으로 겨풀에 대한 경엽처리효과(莖葉處理效果)와 피를 위시한 기타 잡초종(雜草種)에 대한 발생전처리효과(發生前處理效果)를 동시에 평가(評價)하였다. 폿트를 이용하여 plastic house에서 수행(遂行)되었으며, 주요(主要) 결과(結果)를 다음과 같이 요약(要約)할 수 있다. 1. 약제처리후(藥劑處理後)의 경시적(經時的)인 달관평가(達觀評價)에 의하면, glyphosate에 oxyfluorfen을 혼용(混用)함으로써 겨풀의 살초속도(殺草速度)와 살초효과(殺草效果)가 모두 향상(向上)되었으나 alachlor, simazine, gluphosinate 또는 quizalofop-ethyl의 혼용(混用)으로는 약효발현(藥效發現)이 지연되었고, paraquat 혼용(混用)으로는 효과(效果)가 빨랐던 반면(反面) 약효(藥效)는 떨어지는 경향(傾向)이었다. 2. 처리후(處理後) 30일(日)에의 겨풀 생체중(生體重)으로 보아, 공시약제(供試藥劑) 각각의 고약량(高藥量) 수준(水準)(실용(實用)의 1/2) 혼용(混用)에서는 alachlor 또는 paraquat 이외의 모든 조합(組合)에 서 glyphosate 단제(單劑) 보다 비등(比等) 이상(以上)의 살초력(殺草力)을 나타내었다. 3. Glyphosate에 대한 공시(供試) 약제(藥劑)의 어떤 조합(組合) 혼용(混用)에서도 synergism은 인정(認定)되지 않았고, 오히려 저약량수준(低藥量水準)의 simazme이나 paraquat 혼용(混用)에서는 유의적(有意的)인 길항작용(拮抗作用)이 인정(認定)되었다. 4. 피 및 기타 초종(草種)에 대한 토양잔류성(土壤殘留性) 제초효과(除草效果)는 glyphosate와의 혼용(混用) 여부(與否)에 관계없이 oxyfluorfen, alachlor, simazine 및 일부 quizalofop-ethyl이 처리(處理)된 곳에서 인정(認定)이 되었다.

• The Plant Pathology Journal
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• 제19권2호
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• pp.97-101
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• 2003

This study was conducted to determine the efficacy of Epicoccosorus nematosporus for the control of Eleocharis kuroguwai and to evaluate the meteorological factors which affect weeding efficacy in field conditions for three years (1996-1998). The best time to control E. kuroguwai with E. nematosporus as a biological control agent in the field was in July, when temperature ranged from 20.4 to $23.4^{\circ}C$; the surface wetness duration was 12.6-16.1 hours, and application time of 6:00 p.m. and 8:00 p.m.; and weeding efficacy was 81-90%. On 10 June 1996 in Milyang area, where the field experiments were performed, mean temperature was $16.5^{\circ}C$ with 11.3 hours of dew duration. Meanwhile, on 20 Aug. 1996 the temperature was $21.3^{\circ}C$ with 15.4 hours of dew duration. During these periods, the weeding efficacy was recorded at 61.8 and 60.8%, respectively. Time required for complete plant death was 25.8 and 25.6 days at application times 10 June and 20 Aug., respectively. At the time of application on 7,18, and 27 July 1996, mean temperature was 20.4-$23.4^{\circ}C$ with 12.6-16.5 hours of dew duration. The weeding efficacies of these periods were very hi일 with 81.4-90.8%. Three years of field observations from 1996 to 1998 showed that infection in the field can occur at any time through the summer season, although total infection rates vary between months and between years. In 1996, plant infection rapidly increased from 56% on 30 June, 82.4% on 15 July, 94.6% on 15 August, and 92.8% on 15 September under favorable meteorological conditions such as minimum temperature of $17.6^{\circ}C$ and maximum temperature of $27.1^{\circ}C$, with 86% relative humidity and 977.5 mm of rainfall during E. kuroguwai growing season. However, in 1997, the disease incidence was very low because of unfavorable weather conditions brought about by the hot temperature and the low amount of rainfall at 321.5 mm. Disease progress was slow from 24.4% on 30 June to 49.2% at the end of the growing season.