• 한국도서관정보학회지
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• 제9권
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• pp.213-240
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• 1982

Today, one of the major pressures that libraries have been facing is the rapid growth of publications. Due to the rapid growth of publications, libraries have been faced the shortage of stack as well as quality deterioration of library collections. Naturally, these disa n.0, ppointed the users and made the present library activities weak and inadequate. One of the desirable actions in remedying these problems is to weed library collections properly and regularly. Weeding methods used in libraries are derived from the judgement by subject specialists, from the examining the imprint date and the past use patterns of a volume. Among these methods, the past use patterns are highly predictive of the future use, and can be used to create meaningful weeding criteria. Since the libraries in Korea have emphasized on numbers of library collection in the past, the libraries have neglected weeding library collections. Now, we must turn our concern toward the weeding library collections, and the attitude of the library services to the users must change from passive to active.

• Journal of Biosystems Engineering
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• 제39권1호
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• pp.11-20
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• 2014

Purpose: Walking type cultivator used for weeding generated excessive handle vibration as well as bouncing motion depending on the weeding speed. This research was conducted to define a design factor of the rotary weeding blades for reducing soil reaction forces as well as hand vibration. Methods: The motion and forces acting on the rotary blades were reviewed to find out the most influencing parameter on hand vibration. The installation angle (IA) of the blade was selected and analyzed to determine the condition of no reaction force less. For removing the unnecessary upward soil reaction, the design factor theory of weeding blade was suggested based on geometrics and dynamics. For evaluation of design factor theory, the experiment in situ was performed base on ISO 5349:1. The vibration $a_{hv}$ and theoretical value $X_{MF}$ were compared with two groups that one was positive group ($X_{MF}$ > 0) and the other was negative group ($X_{MF}$ < 0). Results: $X_{MF}$ was derived from rotational velocity, forward velocity, disk diameter, weeding depth, blade's width and IA of blade. Two groups had significant difference (p < 0.05). In aspect of the group mean total exposure duration, positive group was 17.53% bigger than negative group. When disk radius 100, 150 and 200 mm, minimum IAs were $4{\sim}27^{\circ}$, $3{\sim}15^{\circ}$ and $2{\sim}10^{\circ}$, respectively. A spread sheet program which calculated XMF was developed by Excel 2013. Conclusions: According to this result, minimum IA of weeding blade for soil reaction reduction could be obtained. For reduction hand-arm vibration and power consumption, minimum IA is needed.

• 한국작물학회지
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• 제23권3호
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• pp.55-65
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• 1978

Upland weed control in Korea has been in dilema with the radical problems prior to weed problems, as it were, poor farming conditions, low yielding, no farmers concern, lack of political cares, and low returns for farming, etc. In these respects, the study was intended to collect all concerns to upland farming conditions and to array all research informations contributed upon Korea upland weeding, and at last interpreted its problems in order of importance. Especially expecting the reasonable and common use herbicides upon the most uplands in Korea, the crop compatibility and weeding efficacy by the most herbicides upon each crops were investigated from the experiment results. Among other interpretations of research results, the most important and first of all acceptance was for the direction and methods of weed research to be rationalized. And that weeding programs in level of upland farmers should be cautionsely and gradually propagated was interpreted to be accepted. Also, for the reasonable development of upland weeding situation in near future, the integrated promotion of upland farming rationalization is suggested by schematic explanations.

• Weed & Turfgrass Science
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• 제7권2호
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• pp.120-129
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• 2018

This experiment was conducted to find the most suitable crop establishment method and weed management practices for transplanted aman rice in Bangladesh. Rice variety Bangladesh Rice Research Institute (BRRI) dhan44 was used as planting materials where three crop establishment methods ($T_1$: direct wet seeding by drum seeder; $T_2$: hand broadcasting; $T_3$: transplanting) and four weeding options ($W_1$: Hand weeding (HW); $W_2$: BRRI weeder+HW; $W_3$: Herbicide+HW; and $W_4$: no weeding) were tested. Among the crop establishment methods, the highest grain yield ($5.12t\;ha^{-1}$) was obtained with the $T_3$, while the highest benefit cost ratio (BCR) of 2.08 was found in $T_2$. In case of the weed management method, $W_1$ showed superior results on the plant $density/m^2$ (139.66) at 60 days after transplanting (DAT), grain yield ($4.97t\;ha^{-1}$), and BCR (2.03). On the other hand, the highest plant dry matter (36.20 g) at 60 DAT and the highest yield ($6.10t\;ha^{-1}$) were obtained in a $T_3W_1$ combination. The results of this study show that the productivity of rice during aman season could be most significantly increased with the use of transplanting ($T_3$) alone, hand weeding ($W_1$) alone, or a combination of the two methods ($T_3W_1$).

• Journal of Biosystems Engineering
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• 제39권1호
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• pp.1-10
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• 2014

Purpose: This research was conducted to evaluate feasibility of a crank-type walking cultivators for weeding in furrowed upland. Methods: A walking cultivator developed by RDA was selected and evaluated with its working speed (S), cultivation depth (CD) and weeding performance (WP). The evaluation was performed in upland field on July and August, 2012. Also kinematic analysis of the machine was performed to draw out design improvements. Results: S in flat, uphill and downhill were about 0.11 m $s^{-1}$, 0.11 m $s^{-1}$, and 0.13 m $s^{-1}$ respectively. It was found that S had a low relevance with user conditions. The CD was 35 ~ 40 mm which was satisfied with the RDA guide for weeding machine. A wide variation was observed in values of WP depending on the growth stages of weeds and field conditions. The cultivator showed low performance in eliminating the well-grown weeds. Kinematic simulation revealed that high forward speed caused a high ratio of un-weeded area. Conclusions: The weeding performance of the cultivator was satisfactory for weeds in early growth stage but it showed difficulties in handling on up-slope and in entering up-land. Specifically, the weight of the cultivator was judged as overweight for female workers. The crank-hoe type cultivator was judged as unsuitable for small walking type machine due to weight of the four-bar linkage system. Kinematic analysis revealed that the ratio of crank speed to the ground speed must be 850 rpm s $m^{-1}$ (255 rpm based on 0.3 m $s^{-1}$) or greater to avoid uncultivated area. Selection of forward speed is a decisive factor in designing the weeding cultivator.

• 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.

• 한국유기농업학회지
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• 제17권4호
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• pp.501-517
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• 2009

노지재배 케일의 재배 포장 조건과 재배 작기에 따른 멀칭재료와 제초방법이 케일의 생육과 잡초 발생에 미치는 영향을 구명하고자 재배 포장은 밭토양과 논토양에서 수행하고, 재배 작기는 봄 작형과 가을 작형에서 수행하였다. 밭토양에서의 가을재배 작형의 멀칭재료에 따른 지온은 멀칭처리가 $0.9{\sim}2.0^{\circ}C$ 높았다. 잡초 방제가는 멀칭종이 처리가 91% 이상이었고, 멀칭재료와 제초방법에 따른 잡초 방제시간은 멀칭종이+기계제초 처리가 무멀칭+손제초 대비 70% 절감되었으며, 케일의 수량은 관행재배와 비슷하였다. 밭토양에서의 봄재배 작형의 종이멀칭 처리는 기온이 비교적 낮은 4월은 무멀칭대비 지온이 높았고 온도가 높아지는 5월과 6월에는 낮았다. 우점잡초는 명아주가 우점 하였으며, 잡초 방제가는 멀칭종이 처리가 52% 이상이었고, 멀칭재료와 제초방법에 따른 잡초 방제 시간은 멀칭종이+기계제초 처리가 무멀칭+손제초 대비 75% 절감되었으며, 케일의 수량은 관행재배대비 34% 증수되었다. 논토양에서의 봄재배 작형의 우점잡초는 둑새풀이 우점 하였으며, 잡초 방제가는 멀칭종이 처리가 43% 이었고, 멀칭재료와 제초방법에 따른 잡초 방제시간은 멀칭종이+기계제초처리가 무멀칭+손제초 대비 80% 절감되었으며, 케일의 수량은 관행재배대비 26% 증수되었다.

• 한국환경과학회지
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• 제24권2호
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• pp.253-260
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• 2015

Enlargement of street tree planting area is the proper and effective solution to reduce carbon dioxide. This solution bases on the ability of carbon storage and uptake by tree metabolism. However, the circumstance of road side has fatal disadvantages in tree metabolism such as growth and maturity because cutting and filling of roadsides cause unnatural soil composition. In this point, early rootage of street tree is the main factor of reducing carbon dioxide. This study aimed to find a appropriate transplantation planting method for sound and rapid rootage of street tree. For the study, Korean Mountain Ash(Sorbus alnifolia) were used for experimental groups. The groups were categorized by three groups such as trees produced on container with mulching treatment, trees produced in outdoor with mulching treatment, trees produced on container with weeding treatment. Each group consisted 10 trees with same size and transplanted in experimental site. Five months after transplanting, each group was estimated the biomass and carbon storage through a direct harvesting method. According to results of the study, the carbon storage of trees produced on container with mulching treatment is 42% more than trees produced in outdoor with mulching treatment. And the carbon storage of trees produced on container with mulching treatment is 19.5% more than trees produced on container with weeding treatment. These results may imply that transplantation of container produced tree with mulching treatment is the most rapid rootage among other groups. The weeding treatment is more effective than mulching treatment for rapid rootage of street trees.

• 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.

• 한국잡초학회지
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• 제4권1호
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• pp.26-38
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• 1984

본연구(本硏究)는 수도(水稻) 두 품종(品種) (밀양(密陽)23호(號)와 사도미노리)을 공시(供試)하여 播種方法(파종방법)(직산파(直散播)와 직조파(直條播))과 이앙방법(移秧方法)(기계(機械) 및 손이앙(移秧))을 달리 하는 4종작부(種作付) 방식(方式)으로 재배(栽培)하면서 수도수량(手稻收量) 감모방지(減耗防止)에 가장 효과적인 제초시기(除草時期)와 회수(回數)를 구명하고저 시도되었다. 제초처리(除草處理)는 전보(前報)아 같이 잡초방임구(雜草放任區), 무잡초구(無雜草區), 이앙후(移秧後) 3, 6, 9, 12주(週)의 각 1회제초구(回除草區) 및 3주(週)와 9(週)의 2회제초구(回除草區) 등(等) 7종(種)을 공시(供試)하였으며 시험결과(試驗結果)를 요약하면 다음과 같다. 1. 화본과잡초군(禾本科雜草群)과 광엽잡초군(廣葉雜草群)의 효과적인 방제는 파종(播種)(이앙(移秧))후(後) 6주(週)의 1회(回)로 판단되었으며, 3주(週)의 1회제초(回除草)는 재발생(再發生) 때문에, 그리고 9주(週)의 1회제초(回除草)는 이미 발생(發生)된 잡초(雜草)의 경합해(競合害) 때문에 문제(問題)가 되었다. 2. 사초과잡초군(雜草群)의 효과적인 방제는, 기계이앙(機械移秧)의 경우에만 이앙후(移秧後) 3주(週)의 1회제초(回除草)로 충분하였으며, 그 밖의 작부양식하(作付樣式下)에서는 파종(播種(이앙(移秧))) 후(後) 3주(週)와 9주(週)의 2회제초(回除草)가 바람직하다. 3. 수도(水稻) 생육량(生育量) 감소(減少)를 최소화(最小化)하기 위한 제초(除草)는 파종(이앙)후 3주(週)와 9주(週)의 2회(回)처리였으며 경우에 따라서는 수종후(收種後) 처리(處理)를 추가함이 기대되었다. 4. 수도수량(水稻收量)으로 보아 밀양(密陽) 23호(號)는 파종(播種)(이앙(移秧)) 후(後) 6주(週)가 최대잡초경합시기(最大雜草競合時期)로서 3주(週)와 9주(週)의 2회제초(回除草)가 기대(期待)되며, 특히 사도미노리를 기계 및 손이앙(移秧)할 경우에는 이앙후(移秧後) 3주(週)의 1회제초(回除草)나 6주(週)의 1회제초(回除草)나 6주(週)의 1회제초(回除草)로도 효과적이었다. 5. 잡초해(雜草害)로 기인된 수수감소(穗數減少)는 사도미노리보다 밀양(密陽)23호(號)에서 큰 경향이었고 수수(穗數) 확보에 대한 최대 경합시기는 대체로 파종(이앙) 6주후(週後)였으며, 3주(週)와 9주후(週後)의 2회제초(回除草)가 바람직하였다. 6. 면적당수수(面積當穗數) 이외의 수도수량구성요소(水稻收量構成要素)들에서는 잡초경합해(雜草競合害)에 따른 변이폭(變異幅)이 적었으며 따라서 제초시기(除草時期)나 회수차이(回數差異)에 따른 반응(反應)은 면적당수수(面積當穗數)의 반응(反應)과 유사하였다. 7. 직파(直播)에서는 파종후(播種後) 9~15주(周)의 수도생육(水稻生育)을, 관행이앙(慣行移秧)에서는 이앙후 6~15주(週)의 수도생육(水稻生育)을 극대화(極大化)하도록 제초방안(除草方案)을 계획(計劃)하는 것이 수량확보(收量確保)에 유리할 것으로 판단되었다.