• Journal of Biosystems Engineering
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• 제7권2호
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• pp.36-44
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• 1983

Farm population was rapidly decreasing due to shift of the people from farm sector to the non-farm sector caused by the economic growth of the country. Especially, a great shortage of farm labor in busy farming period in June and October is becoming a serious problem in maintaining or promoting land productivity. The peak of labor requirement in summer is caused by rice transplanting and barley harvesting. In order to reduce the restrictions imposed on farm management by the concurrence of labor requirement and the lack of labor, the experimental study for mechanization of barley harvesting has been carried out in the fields. 1. The machines for barley harvesting were knap-sack type reapers, windrow reaper (power tiller attachment), binder and combine. The order of higher efficiency of machine for barley harvesting was combine, binder, windrow reaper (WR), knapsack type reaper 1(KSTR1), and knap sack type reaper 2(KSTR2; mist and duster attachment). 2. The ratio of grain loss for the manual, binder, and combine plot was about four percent of total field yield. 3. The total yield of barley in 35 days and 40 days harvesting after heading were 514 kg and 507kg per 10 ares respectively. The yield of 35 days-plot was higher than other experimental plots. 4. The lowest yield was recorded in 30 days-plot due to the large quantity of immatured grains and having lighter 1000-grain weight. The ratio of immatured grains was 2.66 percent and 1000-grain weight was 29.4 grams. 5. The total harvesting cost of the windrow reaper was 10,178 won per 10 ares. It was the lowest value compared to other machines. The next were combine, binder, KSTR1, KSTR2, and manual in sequence. As a result, the optimum time of barley harvesting for mechanization was 35-40 days after heading. Combine, binder, and windrow reaper were recommended as the suitable machines for barley harvesting in the work efficiency. However, in total harvesting cost, the windrow reaper was the most promising machine for barley harvesting.

• Journal of Forest and Environmental Science
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• 제30권1호
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• pp.107-112
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• 2014

The productivity and cost of clear cutting operations were examined to broaden our knowledge on the harvesting system in a Larix leptolepis stand of Korea. The harvesting system was divided into tree operations which were chainsaw (STIHL MS440) felling, tower yarder (Koller301-4) yarding and harvester (WOODY H50) processing. The average cycle time of felling, yarding and processing were 98 s/cycle, 245 s/cycle and 150 s/cycle. The total stump-to-pile operational productivity was 43.07 $m^3/hr$. The highest production activity was the felling 17.93 $m^3/hr$, followed by the productivity of processing 15.62 $m^3/hr$ and then by the productivity of yarding 9.52 $m^3/hr$. In addition the total stump-to-pile operational cost was 24,086 $won/m^3$. The highest cost activity was the yarding 14,557 $won/m^3$ (60.4% of the total cost), followed by the costs of processing 8,461 $won/m^3$ (35.2%) and then by the costs of felling 1,068 $won/m^3$.

• Journal of Forest and Environmental Science
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• 제33권2호
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• pp.147-153
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• 2017

The purpose of this study was to examine productivity and cost of tree-length harvesting using cable yarding system in a larch (Larix leptolepis) clear-cutting stand located in Pyeongchang-gun, Gangwon-do. We used tree-length harvesting method using cable yarding system with a tower yarder HAM300. The productivity was $17.6m^3/hr$ for felling, $12.4m^3/hr$ for delimbing, $4.2m^3/hr$ for yarding, and $8.1m^3/hr$ for processing. The total cost of the harvesting system was $48,381won/m^3$, which was majorly composed of yarding operation cost, at $40,169won/m^3$ (79.3%), while felling had the lowest cost at $1,154won/m^3$ (4.1%). Major factors affecting felling and processing productivity was tree volume and the number and thickness of branches for delimbing productivity. In addition, we suggest that training and education for machine operators were critical to improve yarding productivity.

• Journal of Forest and Environmental Science
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• 제24권1호
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• pp.1-14
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• 2008

Clearcutting has been the dominant harvesting method in British Columbia (representing 95% of the total area harvested annually). However forest managers are increasingly recommending the use of alternative silvicultural systems and harvest methods, including various types of partial cutting, to meet ecological and social objectives. In this study we compared harvesting productivity and harvesting costs between treatments through detailed and shift level time studies in 300-350 year-old Interior Cedar-Hemlock stands in British Columbia, Canada. Recommendations for improving operational planning/layout and the implementation of clearcut and partial cutting silvicultural systems were made. Harvesting costs varied in the ground-based clearcut treatments from $10.95/$m^3$ - $15.96/$m^3$ and $16.09/$m^3$ - $16.93/$m^3$ in the group selection treatments. The ground-based group retention treatment had a cost of $13.39/$m^3$, while the cable clearcut had a cost of $15.70/$m^3$. An understanding of the traditional and alternative wood products that could be derived from the harvested timber was imperative to increasing the amount of merchantable volume and reducing the corresponding harvesting costs. Stand damage was greatest in the group selection treatments; however, mechanized felling showed an increase in stand damage over manual felling while grapple skidding showed a decrease in skidding damage compared to line skidding.

• Journal of Biosystems Engineering
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• 제35권6호
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• pp.367-372
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• 2010

Consumption of pepper, a major spice vegetable used for seasoning Kimchi, continues to increase, but cultivation is in decline due to shortage of rural labor in Korea. The 39.2% of total labor requirement for conventional pepper cultivation was available for harvesting work. Therefore conventional manual harvesting should be turned to mechanical harvesting for labor-saving, cost-reducing and easy work. Surveys on conventional pepper cultivation patterns, labor requirements for various pepper cultivation works, and farmers' opinions on the mechanization of pepper harvesting were conducted to obtain basic informations. The labor requirement for pepper harvesting was 954 h/ha out of a total labor requirement of 2,436 h/ha for pepper cultivation. Harvesting was the hardest work, and hiring workmen for harvesting was also difficult. Farmers preferred to develop a small-scale pepper harvester using agricultural tractor or cultivar. Most farmer agreed to change cultivation pattern for mechanization of pepper harvesting, but hesitated to adopt new one-time-harvesting pepper varieties.

• Journal of Forest and Environmental Science
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• 제32권2호
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• pp.189-195
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• 2016

Logging equipment and method have a major influence on harvesting productivity and cost. This study investigated the productivity and operational costs of tree-length cable yarding system using HAM300, a domestically developed tower yarder. We tested HAM300 for thinning operation in Pinus densiflora stands at Gangreung, Gangwon-do on April, 2014. To assess the productivity we conducted time study for each stage of the operation. When the average time/cycle was examined for each stage of the operation, the longest was for yarding (241 sec), followed by delimbing (237 sec), felling (153 sec), and processing (103 sec). Furthermore, productivity for felling was $8.6m^3/hr$, followed by delimbing ($5.1m^3/hr$), yarding ($3.5m^3/hr$), and processing ($8.1m^3/hr$). The total cost for the tree-length logging system was $58,446won/m^3$, of which the majority was incurred by the yarding cost at $46,217won/m^3$ (79.3%), whereas the lowest cost was for felling at $2,359won/m^3$ (4.1%). We suggest that it is necessary to foster specialized operators and provide training in operating the tower yarder thereby implementing efficient harvesting system resulting from low-cost yarding.

• 한국작물학회지
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• 제56권4호
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• pp.400-403
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• 2011

고구마 수확단계에서 작업체계에 따른 생력효과를 조사하고자 순치기와 1열식과 2열식 수확기를 이용하여 시험을 수행한 결과를 요약하면 다음과 같았다. 1. 고구마 수확단계 작업체계는 순치기+비닐제거+2열식 기계수확 +인력굴취가 ha당 106.4시간, 순치기+비닐제거+1열식 기계수확 +인력굴취가 ha당 111.3시간 및 순치기와 비닐제거 작업을 생략하고 1열식 기계수확+인력굴취가 당 107.6시간으로 관행(인력 333.2시간/ha) 대비 각각 68.1%, 66.6% 및 66.8%의 생력효과가 있었다. 2. 고구마 손상개수율은 인력수확이 8.6%인데 비해 기계 2열식이 4.4%, 기계1열식이 5.3%로 약 43.9%가 적게 발생되었으며, 품종에 손상개수율은 연미 6.2%, 신천미5.1%, 하얀미 4.7%, 건미 3.4% 순으로 차이가 있었다. 3. 수확단계 비용절감효과는 ha당 고구마 손상개수율을 포함한 수확단계의 비용이 관행(인력) 2,963천원에 비해 고구마 순치기와 수확기의 이용에 의해 62.9~81.2%인 1,865~2,406천원 절감되었다.

• 한국산림과학회지
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• 제104권2호
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• pp.221-229
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• 2015

본 연구는 강원도 평창군 가리왕산의 낙엽송 인공림을 대상으로 효율적인 임목수확시스템 구축을 위해 타워야더(Koller K301-4)에 의한 전간간벌수확시스템의 생산성 및 비용분석을 실시하였다. 수확시스템은 벌목, 가지정리, 집재, 조재, 집적작업으로 구성하여 요소작업별 비용을 분석하였다. 총 수확비용은 41,707원/$m^3$으로서 벌도작업비용 1,315원/$m^3$(3.2%), 가지정리작업비용 3,127원/$m^3$(7.5%), 집재작업비용 20,083원/$m^3$(48.2%), 조재작업비용 12,143원/$m^3$(29.1%), 집적작업비용 5,039원/$m^3$(12.1%) 등으로 구성되었다. 수확시스템비용 중에서 가장 높은 비중을 차지하는 집재작업에 대하여 평균집재시간 예측모델식을 개발하여, 수확시스템비용에 대한 인자별 영향력 분석을 위해 민감도분석을 실시하였다. 인자별 수확시스템비용에 대한 증감율은 가로집재거리가 약 5.2%, 세로집재거리는 약 3.0%의 증가를 규칙적으로 나타내었다. 집재본수는 많아질수록 수확시스템비용 증감율의 폭은 작아지는 것으로 나타났으며, 집재본수 4~5본에서 감소폭 둔화현상이 발생되었다. 따라서 집재본수인자가 수확시스템비용에 가장 큰 영향을 미치고, 다음으로 세로집재거리인자와 가로집재거리인자의 순으로 영향을 주는 것으로 나타났다.

• 대한환경공학회지
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• 제36권5호
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• pp.333-341
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• 2014

본 연구에서는 양도 초등학교에 강우량과 집수면적, LPCD를 고려하여 빗물이용시설을 설치하였다. 빗물이용시설은 학교 내 외의 상수를 대체하고자 하는 목적으로 설계되었다. 용량은 2톤으로 학교 용수의 34.4%를 대체할 수 있었으며 1년의 2/3정도인 237일 동안 빗물을 사용할 수 있었다. 총 세 차례의 수질검사 결과 일반 세균을 제외한 나머지는 먹는 물 수질에 적합하였다. 또한 동시간에 조사한 주변 지하수는 일반세균을 비롯한 질산성질소, 증발잔류물이 기준치를 초과하였다. 빗물의 수질 및 수량을 고려한 결과, 양도초등학교의 경우 빗물을 대체용수로서 사용하기에 적합하였다. 빗물시설에 대한 경제성 분석 결과, 내구연수 10년인 빗물이용시설은 B/C (Benefit-Cost Ratio) 비율이 1.70으로 경제성 편익이 비용보다 큰 걸로 나타났다. 특히 본 연구에서 고려한 사회적인 요인 외에도 금액으로 환산하기 힘든 홍수방지, 가뭄대비, 교육 효과가 있어 사회적 편익이 더욱 증가할 것으로 예상된다.

• Asian-Australasian Journal of Animal Sciences
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• 제18권7호
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• pp.1029-1035
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• 2005

A 3${\times}$4 factorial field experiment with a complete randomised split-plot design with four replicates was conducted from June 2002 to March 2003 at the experimental farm of the Nong Lam University, Ho Chi Minh City, Vietnam, to determine effects of different harvesting heights (10, 30 and 50 cm above the ground) and cutting intervals (45, 60, 90 and 285 days) on yield of foliage and tubers, and chemical composition of the foliage. Cassava of the variety KM 94 grown in plots of 5 m${\times}$10 m at a planting distance of 30 cm${\times}$50 cm was hand-harvested according to respective treatments, starting 105 days after planting. Foliage from the control treatment (285 days) and all tubers were only harvested at the final harvest 285 days after planting. Dry matter and crude protein foliage yields increased in all treatments compared to the control. Mean foliage dry matter (DM) and crude protein (CP) yields were 4.57, 3.53, 2.49, and 0.64 tonnes DM $ha^{-1}$ and 939, 684, 495 and 123 kg CP $ha^{-1}$ with 45, 60, 90 and 285 day cutting intervals, respectively. At harvesting heights of 10, 30 and 50 cm the DM yields were 4.27, 3.67 and 2.65 tonnes $ha^{-1}$ and the CP yields were 810, 745 and 564 kg $ha^{-1}$, respectively. The leaf DM proportion was high, ranging from 47 to 65%. The proportion of leaf and petiole increased and the stem decreased with increasing harvesting heights and decreasing cutting intervals. Crude protein content in cassava foliage ranged from 17.7 to 22.6% and was affected by harvesting height and cutting interval. The ADF and NDF contents of foliage varied between 22.6 and 30.2%, and 34.2 and 41.2% of DM, respectively. The fresh tuber yield in the control treatment was 34.5 tonnes $ha^{-1}$. Cutting interval and harvesting height had significant negative effects on tuber yield. The most extreme effect was for the frequent foliage harvesting at 10 cm harvesting height, which reduced the tuber yield by 72%, while the 90 day cutting intervals and 50 cm harvesting height only reduced the yield by 7%. The mean fresh tuber yield decreased by 56, 45 and 27% in total when the foliage was harvested at 45, 60 and 90 day cutting intervals, respectively. It is concluded that the clear effects on quantity and quality of foliage and the effect on tuber yield allow alternative foliage harvesting principles depending on the need of fodder for animals, value of tubers and harvesting cost. An initial foliage harvest 105 days after planting and later harvests with 90 days intervals at 50 cm harvesting height increased the foliage DM and CP yield threefold, but showed only marginal negative effect on tuber yield.