• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.3
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• pp.199-209
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• 2021

Alternative methods of rock cutting have been introduced to substitute and to improve the traditional mechanical rock excavation methods (e.g., TBM and roadheader). Undercutting methods have been recently studied in some countries. In undercutting, several additional cutting parameters are involved in its cutting process compared to the traditional rock-cutting. As a fundamental study, this paper introduces the concept of undercutting method with actuated disc, lab-scaled testing system, and testing procedures of undercutting by the system. Also, we present the calculation methods of cutter forces and specific energy, and discuss the results of undercutting tests compared to those of traditional rock-cutting methods.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.22 no.11
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• pp.1106-1112
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• 2012

This paper deal with a technique for monitoring machining conditions by measuring the vibration of cutting forces at milling machining. The vibrations of cutting forces in milling process were measured and analyzed to be related with processing parameters. The magnitude of cutting force is linearly proportional to the feed rate and cutting depth, and frequency of cutting force is linearly proportional to the rotating speed. Wired and wireless communication methods were applied in transmitting the measured vibration signals and the two methods were compared. The magnitude of the vibration signals transmitted by the wireless communication method was similar to that transmitted by the wired communication method.

• International Journal of Advanced Culture Technology
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• v.10 no.4
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• pp.219-225
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• 2022

In November 1983, Deng Sanmu's wife, Zhang Jianquan, donated a large number of Deng Sanmu's original seal carving stones and seal cutting scores to the Heilongjiang Provincial Museum in China. Therefore, the Heilongjiang Provincial Museum of China is the richest and most authoritative place to collect Deng Sanmu's original seal cutting stones and seal carving scores. According to the fieldwork, the original seal cutting stones and the seal cutting score donated by Deng Sanmu's wife, Zhang Jianquan, include Deng Sanmu's seal cutting inscriptions made between 1922 and 1963. In addition, Deng Sanmu's own life and career in the art are documented in detail in his markings, so the seal cutting inscriptions of Deng Sanmu in the collection of the Heilongjiang Provincial Museum of China are quite representative. We paper is a documentary review and study of the seal inscriptions of Deng Sanmu in the collection of the Heilongjiang Provincial Museum in China. For the accuracy and richness of this study, a total of 89 representative seals in the collection are used as primary sources to study Deng Sanmu's seal cutting emulation method. The specific content is centered on ancient seals, Qin seals, and Han seals, from which the lineage of Deng Sanmu's emulation methods of seal cutting is further clarified.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2003.10a
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• pp.66-70
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• 2003

Recently, environmental conscious machining becomes one of the most important technology in modern manufacturing industry. Especially in metal cutting, cutting fluid often results in many environmental problems. Many technologies have been developed to reduce the problems of the cutting fluid. But most of the technologies need another devices which sometimes require large space and also are very expensive, such as cooling system. In this paper, air compressor is only used to replace the functions of cutting fluid as semi-dry cutting. Cutting forces, cutting moments, and tool wear were measured to obtain cutting characteristics, and were compared with those of dry cutting and non-dry cutting. In the results of the experiments, semi-dry cutting was found to show better cutting performances than dry cutting and non-dry cutting.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1996.04a
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• pp.276-279
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• 1996

This paper deals with the method providing an exact solution to the 3-dimensional guillotine cutting stock problem. We suggest a 3-stage sutting method using the property that cubic material has to be cut into 2-dimensional planes firstly. This method requires more stocks that the general guillotine cutting methods but can save work force. By using the 1-dimensional dynamic programming, we reduce the computational time and the memory requirement in the 3-stage guillotine cutting method.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.6
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• pp.159-167
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• 2008

Cooling lubricants are used in machining operations in order to reduce friction at the tool-chip and tool-workpiece interfaces, cool both chip and tool, and remove chip. Furthermore, they influence a strong effect on the shearing mechanisms and, consequently, on the machined surface quality and tool wear. However, several researchers state that the costs related to cutting fluids is frequently higher than those related to cutting tools. Moreover, the cooling lubricants cause an increase in both worker's health and social problems related to their use and correct disposal. Therefore, many researchers have focused on the environmentally conscious machining technologies. One of the technologies is known as MQL(Minimum Quantity Lubrication) machining. In this paper, an experimental model to obtain the optimal cutting conditions in MQL turning was suggested, and the effects of cutting conditions on surface roughness and cutting force were analyzed. For these purposes, FFD (Fractional Factorial Design) and RSM (Response Surface Methods) were used for the experiment. Cutting force and surface roughness with different cutting conditions were measured through the external cylindrical turning of Al 6061 based on the experiment plan. The measured data were analyzed by regression analysis and verification experiments with random conditions were conducted to confirm the suggested experimental model.

• Nuclear Engineering and Technology
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• v.55 no.11
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• pp.4181-4190
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• 2023

Nuclear power plants are subjected to various processes during decommissioning, including cutting, decontamination, disposal, and treatment. The cutting of massive bio-shields is a significant step in the decommissioning process. Cutting is performed near the target structure, and during this process, workers are exposed to potential radioactive elements. However, studies considering worker exposure management during such cutting operations are limited. Furthermore, dismantling a nuclear power plant under certain circumstances may result in the unnecessary radiation exposure of workers and an increase in secondary waste generation. In this study, a cutting scenario was formulated considering the bio-shield as a representative structure. The specifications of a standard South Korean radioactive waste disposal drum were used as the basic conditions. Additionally, we explored the hot-to-cold and cold-to-hot methods, with and without the application of polishing during decontamination. For evaluating various scenarios, different cutting time points up to 30 years after permanent shutdown were considered, and cutting speeds of 1-10nullm²/h were applied to account for the variability and uncertainty attributable to the design output and specifications. The obtained results provide fundamental guidelines for establishing cutting methods suitable for large structures.

• 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 The Korean Society of Grassland and Forage Science
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• v.15 no.1
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• pp.24-29
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• 1995

This experiment was canied out to select the optimum utilization method by various pasture types at National Livestock Research Institute, Suwon in 1992 and 1993. Tne main plot was two pasture types. wfiich were mainly top-grass(orchardgrass dominated pasture) and mainly bottom-grass(perennial ryegrass dominated pasture), and the subplot was three pasture utilization methods (grazing, grazing after the 1st cutting, and alternate utilization of cutting and grazing). Average dry matter yields of pasture were not affected by pasture types, but there was significant difference(p <0.05) by pasture utilization methods. Daily DM production of pasture was increased with alternate utilization of cutting and grazing at two pasture types. Also, pasture availability is increased by mainly top grasses and alternate utilization of cutting and grazing. Soil phsical chracteristics are improved by alternate utilization of cutting and grazing. According to the results obtained from this experiment, it is suggested that alternate utilization of cutting and grazing is effective for dry matter yield, pasture availability and soil phsical characteristics regardless of pasture types in Korea.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.4
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• pp.105-110
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• 1998

In this study, statistical and neural network methods were used to recognize the cutting tool states. This system employed the tool dynamometer and cutting force signals which are processed from the tool dynamometer sensor using linear discriminent function. To learn the necessary input/output mapping for turning operation diagnosis, the weights and thresholds of the neural network were adjusted according to the error back propagation method during off-line training. The cutting conditions, cutting force ratios and statistical values(standard deviation, coefficient of variation) attained from the cutting force signals were used as the inputs to the neural network. Through the suggested neural network a cutting tool states may be successfully diagnosed.