• 한국기계가공학회지
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• 제17권6호
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• pp.83-90
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• 2018

This paper introduces a innovative diamond wire saw cutting technology and its experimental verification that can be utilized for cutting heavy structures. While conventional diamond wire saw cutting technologies such as water cooled cutting method and dry cutting method cause severe environmental problems due to generating massive concrete sludge or dust scattering, the proposed method can eliminate those problems considerably. Through extensive experiments using heavy structure test bed and real bridge pier structure, comprehensive analysis and comparative evaluation about various cutting methods were performed. As a result, the innovative diamond wire saw cutting method could achieve a similar cutting and cooling performance to the water cooled cutting method without generating concrete sludge and it showed an improved cutting and cooling performance to the dry cutting method without dust scattering. Consequently it is confirmed that the suggested cutting technology can be a promising environment-friendly alternative in the field of heavy structure dismantling.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2005년도 추계학술대회 논문집
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• pp.344-349
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• 2005

This paper is studied on the effect of TiAlN coated ball end mill on cutting characteristic of high hardness steels in dry cutting condition without coolant. KP4 steels[HRC32] and STD11[HRC60] heat treated steels wert: used as the workpiece and WC-Co ball end mill and single and multi layer TiAlN coated ball end mill were utilized. Results showed that TiAlN coated ball end mill were increased the cutting length than WC-Co ball end mill in the cutting speed$[245\~320m/min]$ about $2\~5$ times for KP4 steels and about $2.7\~4.3$ times for STD11 heat treated steels. The multi layer TiAlN coated ball end mill is good about $1.2\~1.7$ times for KP4 steels and STD11 steels than single layer coated.

• 한국잠사곤충학회지
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• 제31권1호
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• pp.1-11
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• 1989

뽕나무 고조삽목에 있어서 각 품종별로 삽수피부의 건물량, C/N률, 탄수화물, 단백질 및 핵산 등의 삽목후 경시적 변화를 알아보기 위하여 삽목당일부터 삽목 후 40일까지 10일 간격으로 삽수의 피부를 채취 분석하여 다음과 같은 결과를 얻었다. 1. 뿌리와 신초의 생장은 검운뽕(Morus bombycis KoIDZ)이 가장 왕성하였으며, 다음으로 대륙뽕(Morus Lhou(SER.) KoIDZ.)과 개량뽕(Morus alba L.)순으로 낮았다. 2. 삽수피부의 건물량은 삽수당일 50%내외에서 삽목 후 40일째에는 36% 내외로 약 14%정도 감소하였으며, 뿌리와 신초의 생장이 빠른 검운뽕이 가장 높은 감소율을 보였다. 3. C/N율은 삽목 초기에 감소하다가 뿌리와 신초가 생장함에 따라 10일부터 증가하였으며, 검운뽕은 C/N율이 가장 높았고 개량뽕은 가장 낮았다. 4. 전당의 함량은 삽목 후 40일까지 감소하는 경향이었으나, 10일부터 20일 사이에는 약간의 증가를 보였다. 환원당은 삽목 후 20일까지 서서히 증가하였으며 그 후 감소하였다. 전분은 삽목 후 40일까지 감소하였으며 건물량 감소와 같은 경향이었다. rjadnsQHd은 다른 품종에 비해 전당, 전분의 함량이 많았으며, 뿌리와 신초가 생장함에 따라 소비량도 많았다. 5. 조단백질과 수용성단백질은 삽목 후 10일까지 증가하였으나 그 후 감소하였으며, 검운뽕의 단백질함량이 가장 적었다. 6. RNA는 단백질의 변화와 같은 경향이었으나, 검은뽕의 함량이 가장 많았다. DNA는 함량의 경시적 변화와 품종간 함량의 차이를 보이지 않았다.

• 한국초지조사료학회지
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• 제13권2호
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• pp.78-85
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• 1993

This experiment was carried out to select for the varieties with high environmental adaptability in mountainous pastures of Taekwalyong area, and the evaluation was based on the data of varietal differences of dry matter production and yield components in Tall fescue cutting at various developmental stages in growth period of autumn. The results were summarized as follows; 1. The varieties with high number of tillers per plant(NT) showed a high dry weight of plant(DW) in all autumn cuttings. These varieties(Barce1 and Fuego) may be more adaptable to mountainous pastures of Taekwalyon area than other varieties. 2. The number of tillers per plant(NT) was significantly positive correlated with dry weight of plant (DW), but dry weight of tiller(WT) was not significantly correlated with dry weight of plant(DW) in all autumn cuttings. 3. The multiple regression equations of autumn cutting stages with mean dry weight of plant(DW) and number of tillers per plant(NT) can be used to estimate the cutting time to obtain maximum mean dry weight of plant(DW) and the highest number of tillers per plant(NT). The maximum mean dry weight of plant(DW) and the highest number of tillers per plant(NT) was estimated at the time of 21 Oct. and 26 Oct, respectively. 4. Dead leaves tended to increase greatly after the 2nd cutting(l4 Oct.) in growth period of autumn. 5. The number of tillers per plant(NT) was an important yield component before tiller density achieved equilibrium, but dry weight of tiller(WT, including dead leaves) was of most significant as a yield determinant after maximum tiller density reached in growth period of autumn.

• 한국초지조사료학회지
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• 제14권3호
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• pp.201-205
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• 1994

The objectives of this research are to determine the seasonal and varietal differences of total digestible nutrients(TDN) and in vitro dry matter digestibility(1VDMD) of tall fescue grown in Takwalyon areas, based on the data of preceding paper(Lee et al. 1994b). The results are may be summarized as follows : 1. The values of total digestible nutrients(TDN) and in vitro dry matter digestibility(1VDMD) in 1st cutting were lower than the values of 2nd and 3rd cutting, and it was due to different stages of growth and seasonal difference of climatic conditions in this areas. 2. The relative yield(RY) had negative significantly correlation with in vitm dry matter digestibility(1VDMD) of 1st cutting. 3. Total digestible nutrients(TDN) indicated high positive significant correlation with in vitro dry matter digestility (IVDMD) in all cuttings. 4. The variety of Johnstone showed a high values of total digestible nutrients(TDN) and in vitm dry matter digestibility(1VDMD) of 2nd and 3rd cutting, but Fuego was lower than the other varieties.

• 한국초지조사료학회지
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• 제14권4호
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• pp.257-263
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• 1994

The experiment was canied out to investigate the effects of cutting frequencies (3, 4 and 5 cuts per year) in relation to fertilization of mineral nitrogen on crude protein yield and the contents of crude protein and acid detergent fibre in orchardgms(Dacty1is glomerata L.). Tne results are as follows : 1. The content of crude protein increased according to the increase in cutting frequency and showed the highest in the 1st cut in all treatments. At 4 and 5 cutting frequencies per year, the content of crude protein increased in a large extent according to the increased fertilization of mineral nitrogen. However at 3 cutting frequency, the content of cmde protein appeared higher for no application of mineral nitrogen than for the treatments with fertilization. 2. 'Ihe content of acid detergent fibre(ADF) was considerably reduced at 4 and 5 cutting frequencies and in all treatments, the lowest were recorded in the 1st cut or in the last cut. At 3, 4 and 5 cutting frequencies, the highest ADF were shown in the 2nd cut, 3rd cut and 3rd cut respectively. However, the general trend was that the content of ADF was greatly reduced according to increased level of mineral nitrogen fertilization. 3. The yeild of cmde protein was the highest at 5 cutting frequency(l.2 ton DMIha) and it indicated that the yield of cmde protein increased in accordance to the increase in fertilization of mineral nitrogen and cutting frequency. 4. In all treatments, positive correlation(p<0.001) between the yeilds of crude protein and annual dry matter yield appeared. Negative correIation(p

• 한국기계가공학회지
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• 제3권4호
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• pp.29-36
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• 2004

An experimental study on drilling of stainless steel is conducted using TiAlN coated drills and HSS twist drills with several cutting conditions; feed rate, spindle rotational speed, and dry/wet cutting. The effects of number of hole on the thrust force are examined by cutting force measurement. The flank wear of the drills and the change of hole diameter are quantitatively observed using a vision system. It is found that the thrust force in drilling with TiAlN coated drills decrease under dry and wet machining, whereas the flank wear resistance is improved.

• 한국초지조사료학회지
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• 제12권1호
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• pp.41-48
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• 1992

본 실험은 예취높이와 질소시비수준이 sorghumsudangrass hybrid(Sordan 79)의 고사주, 신지발생(측지+분벽경), 고지의 건물비솔, 총건물수량 등에 미치는 영향을 규명하기 위하여 예취높이(5cm, 10cm, 15cm, 20cm)를 주구로 하고 질소시비수준(150kg,250kg,350kg/ha)을 구로 하여 1988년 5월부터 9월 까지 건국대학교 자연과학대학 사료포장에서 실시한 결과를 요 하면 다음과 같다. 1. 초장은 예취높이와 질소시비수준이 높은 구에서 높게 나타났으며, 특히 고온시에 큰 차이를 나타냈다. 2. 예취후 소사주는 예취 높이가 낮아질수록 증가하였으며 (P<0.01) 질소시비수준에 있어서는 증가될수록 고사주 발생도 높게 나타났다. 3. 예취후 측지의 발생은 예취 높이가 높아질수록 증가하였으며 (P<0.01) 신지의 발생은 질소시비수준이높은 구에서 높은 경향을 보였다. 4.예취높이가 높아질소록 재생건물수량에 있어서 측지가 차지하는 비솔은 증가하였으며(P<0.05), 예취높이가 낮은 구의 재생건물수량은 대부분 분벽경이 차지하였다. 5. 건물수량은 질소시비수준이 높아질수록 모든 구에서 유의적으로 증가하였으며 (P<0.01) 예취높이 20cm구가 대부분 건물수량이 높았다.량이 높았다.

• 한국생산제조학회지
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• 제24권2호
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• pp.256-262
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• 2015

This study has an innovative improvement of the ocher tiles production system that aims to resolve social issue of industrial waste and to meet the customer needs for environmental-friendly building materials. By changing a wet type cutting method to a dry type of ocher tiles production system, the three processes such as cleaning, dehydration, and drying can be removed in existing overall process of 17 steps. Accordingly, the application of the wet type cutting method, which is proposed in this study, makes an increase in ocher tiles production from 1,500 to 1,850 pieces per hour. In particular, industrial wastewater that was emerging as the biggest problem in environmental pollutants in the wet cutting method has been removed. In addition, the most serious problems of noise and dust from the operator side, while developing a device for the dry cutting method, are eliminated through the development of additional equipment.

• 산업경영시스템학회지
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• 제45권4호
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• pp.61-69
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• 2022

The function of coolant in machining is to reduce the frictional force in the contact area in between the tool and the material, and to increase the precision by cooling the work-piece and the tool, to make the machining surface uniform, and to extend the tool life. However, cutting oil is harmful to the human body because it uses chlorine-based extreme pressure additives to cause environmental pollutants. In this study, the effect of cutting temperature and surface roughness of titanium alloy for medical purpose (Ti-6Al-7Nb) in eco-friendly ADL slot shape machining was investigated using the response surface analysis method. As the design of the experiment, three levels of cutting speed, feed rate, and depth of cut were designed and the experiment was conducted using the central composite planning method. The regression expressions of cutting temperature and surface roughness were respectively obtained as quadratic functions to obtain the minimum value and optimal cutting conditions. The values from this formula and the experimental values were compared. As a result, this study makes and establishes the basis to prevent environmental pollution caused by the use of coolant and to replace it with ADL (Aerosol Dry Lubricant) machining that uses a very small amount of vegetable oil with high pressure.