• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.551-555
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• 1993

With the development of modern agriculture, a new cultivating method with high efficiency, good quality and low energy consumption should be developed to satisfy agricultural requirements. After comparing various cultivating patterns and summerizing research results, the submerged up-cut rotary cultivation is predicted to have bright futures and still some problems need to be solved.

• International Journal of Precision Engineering and Manufacturing
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• v.4 no.1
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• pp.23-29
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• 2003

Stencil is used normally as a mask for solder pasting on pad of a printed circuit board (PCB). The objective of this study is to develop a stencil cutting system and determine the optimal conditions to make good-quality stencil by using a Nd:YAG laser. The effects of process parameters such as laser power, type of mask, gas pressure, cutting speed and pulse duration on the cut edge quality were investigated. In order to analyze the cut surface characteristics (roughness, kerfwidth, dross) optical microscopy, SEM microscopy and roughness measurements were used. As a result, the optimal conditions of cutting process parameters were determined, and the practical feasibility of the proposed system was also examined by using a commercial Gerber file for PCB stencil manufacturing.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.989-992
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• 1997

The objective of this study is to develop stencil cutting process and determine optimal conditions which make good-quality stencil by using a Nd:YAG laser. The effects of process parameters such as laser power, type of mask, gas pressure, cutting speed and pulse width on the cut edge quality were investigated. In order to analyze the cut surface characteristics(roughness, kerf width, dross) optical microscopy, SEM photography and roughness test were used. A a results, the optimal conditions of process parameters were determined, and the practical feasibility of the proposed system is also examined by using a commercial gerber file for PCB stencil manufacturing.

• Journal of the Korean Society of Tobacco Science
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• v.14 no.2
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• pp.144-150
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• 1992

This study was carried out to investigate the effect of yield and quality on the harvesting time and methods of stalk cutting in Burley Tobacco.3 harvesting methods and 4 harvesting times of stalk cutting were compared to priming. The yield and quality were high when cut the stalk after second priming in stalk curing. It was also desirable that cut the stalk after second priming in stalk curing. It was also desirable that cut the stalk on 30 days after topping for standard fertilization(N-P2O5-K2O= 17.5-17.5-35.0kg/10a) plot, and 30-35 days after topping for 30% increased fertilization.

• Food Science and Preservation
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• v.19 no.2
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• pp.173-177
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• 2012

Whole apples were cut with a sharp or dull knife, and whole cabbages and crisp lettuce heads were cut into salad or thin strips with a knife or by hand. The fresh-cut apples, cabbages, and lettuce were packed in low-density polyethylene bags and kept at $4^{\circ}C$, and their qualities were investigated. Browning and softening of the apples that were cut with a sharp knife were more delayed than those of the apples that were cut with a dull knife. The soluble solids and pH of the fresh-cut apples were not affected by the sharpness of the cutting blade. The browning indexes of the fresh-cut cabbages and lettuce were significantly lower in the samples that were cut with a knife than by hand and in the samples that were cut into large pieces. The results suggest that the cutting blade sharpness, cutting tools, and cut types affected the quality of the fresh-cut apples and leafy vegetables, and that the cutting methods which minimized the cutting damage should be used to retard the browning and softening of the produce.

• Journal of Biosystems Engineering
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• v.28 no.3
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• pp.231-238
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• 2003

Rose and chrysanthemum are the most popular flowers in Korean floriculture. Sorting flowers is a labor intensive operation in cultivation of the cut flowers and needed to be mechanized. Machine vision is one of the promising solutions for this purpose. This study was carried out to develop hardware and software of a cut flower sorting system using machine vision and to test its performance. Results of this study were summarized as following; 1. Length of the cut flower measured by the machine vision system showed a good correlation with actual length of the flower at a level of the coefficients of determination (R$^2$) of 0.9948 and 0.9993 for rose and chrysanthemum respectively and average measurement errors of the system were about 2% and 1% of the shortest length of the sample flowers. The experimental result showed that the machine vision system could be used successfully to measure length of the cut flowers. 2. Stem diameter of the cut flowers measured by the machine vision system showed a correlation with actual diameter at the coefficients of determination (R$^2$) of 0.8429 and 0.9380 for rose and chrysanthemum respectively and average measurement errors of the system were about 15% and 7.5% of the shortest diameter of the sample flowers which could be a serious source of error in grading operation. It was recommended that the error rate should be considered to set up grading conditions of each class of the cut flowers. 3. Bud maturity of 20 flowers each judged using the machine vision system showed a coincidence with the judgement by inspectors at ranges of 80%∼85% and 85%∼90% for rose and chrysanthemum respectively. Performance of the machine vision system to judge bud maturity could be improved through setting up more precise criteria to judge the maturity with more samples of the flowers. 4. Quality of flower judged by stem curvature using the machine vision system showed a coincidence with the judgement by inspectors at 90% for good and 85% for bad flowers of both rose and chrysanthemum. The levels of coincidence was considered as that the machine vision system used was an acceptable system to judge the quality of flower by stem curvature.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.170-177
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• 2000

Sorting cut roses according to quality is very essential to increase the value of the product. Many factors are involved in determining the grade of cut roses: length, thickness, and straightness of stem, color and maturity of bud, and extra. Among these factors, the stem straightness and bud maturity are considered to be difficult to set proper classification criteria. In this study, a prototype machine and an analysis procedure were developed to grade cut roses according to stem straightness and bud maturity by utilizing color image processing and neural network. The test results indicated 15.8% classification error for stem straightness and 10.0% for bud maturity.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.14 no.1
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• pp.23-29
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• 2008

The market sales of fresh-cut fruit and vegetables have grown rapidly in recent decades as a result of changes in consumer trend. Choosing the proper pretreatment of fruit and vegetables before minimally processing is very important because appearance is the most fundamental factors affecting the quality of fresh-cut products. This review describes the biochemical bases for color changes of fruit and vegetables including browning, discoloration, and color changes of carrots and alliums. Understanding pathway of pigments in minimally processed fruit and vegetable and preventing the way of color change should be emphasized for successive packaging system. This review also describes pretreatment of fresh-cut fruit and vegetables to improve the prolonging the shelf-life and maintenance of its qualities.

• Journal of the Korean Society for Environmental Technology
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• v.19 no.6
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• pp.514-527
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• 2018

This study formed a scenario to improve a water quality by expecting and analyzing a water quality of Jeollabuk-do Seomjingang water system, so calculated a result. As a result, it was analyzed that a water quality is improved at 15.32 % of the maximum BOD, 7.17 % of T-N, and 62.86 % of T-P according to domestic and livestock cut amount by reinforcing discharge water of sewage disposal plant and improving pollutant management plans. It was analyzed that supplementing various cut plans such as establishment of efficient cut plans, plans to decrease pollution loading amount, plans to increase sewage disposal efficiently, pollutant decrease through an expansion of sewage disposal area, and energy recovery from animal dung of Total Pollutant Load Management System, and developing a study on more efficient improvement plans of water quality by considering natural increase and economic development are efficient in an improvement in a water quality.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.9
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• pp.40-46
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• 2003

Synchronizing errors between the spindle motor and the z-axis motor directly influences the cutting characteristics and the thread quality in tapping, because the tapping process is accomplished by synchronizing the movement of the z-axis with the revolutionary spindle motion. Generally synchronizing errors are decided by tile parameters of the servo system and commanded velocity. The excessive synchronizing errors which are induced by the parameter mismatch and high cutting velocity can cause tap breakage due to the abrupt increase of cutting torque or damage the thread accuracy by overcutting the already cut threads. In this paper, the influences of the synchronizing errors on the tapping characteristics in the ultra high-speed tapping will be described and a minimum level of synchronizing errors necessary to maintain the quality of the cut thread will be presented.