• 한국약용작물학회지
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• 제3권3호
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• pp.195-199
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• 1995

다(茶)나무 삽목(揷木)시 삽수(揷穗)의 종류(種類), 상토(床土)의 종류(種類), 생장조정제(生長調整劑) 등이 발근(發根)에 미치는 영향(影響)을 구명(究明)하고자 시험(試驗)을 수행한 결과(結果)는 다음과 같다. 1. 숙지삽(熟枝揷)보다 녹지삽(綠枝揷)에서 발근율(發根率)이 양호(良好)하며 최적(最適) 삽목시기(揷木時期)는 숙지삽(熟枝揷)의 경우 4월 10일경, 녹지삽(綠枝揷)의 경우 6월 10일경이었다. 2. 적정상토(適定床土)는 마사토(磨沙土)이며, 녹지삽(綠枝揷)과 숙지삽(熟枝揷)에서의 발근율(發根率)은 각각 71% , 87%였다. 3. 생장조정제(生長調整劑)인 Oxyberon과 Rootone의 효과(效果)는 숙지삽(熟枝揷)의 경우 대조구(對照區)에 비해 $4{\sim}9%$의 발근율(發根率)을 향상(向上)시켰으나 녹지소(綠枝揷)에서 는 그 효과가 미미(微微)하였다.

• 한국생산제조학회지
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• 제18권3호
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• pp.261-269
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• 2009

Micro end-milling process is applied to fabricate precision mechanical parts cost-effectively. It is a complex and time-consuming job to select optimal process conditions with high productivity and quality. To improve the productivity and quality of precision mechanical parts, micro end-mill wear and cutting force characteristics should be studied carefully. In this paper, high speed machining experiments are studied to construct the optimum process design as well as the mathematical modeling of tool wear and cutting force related to cutting parameters in micro ball end-milling processes. Cutting force and wear characteristics under various cutting conditions are investigated through the condition monitoring system and the design of experiment. In order to construct the cutting database, mathematical models for the flank wear and cutting force gradient are derived from the response surface method. Optimal milling conditions are extracted from the developed experimental models.

• 한국초지조사료학회지
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• 제16권1호
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• pp.17-26
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• 1996

This experiment was carried out to investigate the effects of endophyte staWendophyte-free and -infect) and cutting frequency(3, 4, 5 and 6 timeslyear) on the forage quality of tall fescue(Festuca crnrtzdit~crcerr Schreb.) at the Experimental Field of Grassland and Forage Crops Division. National Livestock Research Institute, Suweon, from 1993 to 1994. 'Ihe results obtained are summarized as follows: CP content of tall fexue was increased with endophyte-free and cutting frequency for two varieties. Crude protein yield(CPY) of tall fescue in 1993 was increased with endophyte-free and cutting frequency for two varieties(P<0.05). In 1994, however. CPY of endophyte-free tall fescue was slightly lower than that of endophyte-infected tall fescue and the higher CPY was observed when tall fescue was harvested 6 times per year. NDF content of tall fescue was not different between endophyte-infected and -free. NDF was decreased with cutting frequency for two varieties in 1993, however. it was not influenced by the endophyte and cutting frequency in 1994. ADF content of tall fescue was not different between endophyte-infected and -free. and it was decreased with cutting frequency for two varieties. IVDMD was not influenced by endophyte, however, it was increased with cutting frequency for two varieties. Based on the results of this experiment, it is suggested that a slight increase in forage quality could be obtained from endophyte-free tall fescue and the quality was increased with frequent cutting.

• 한국정밀공학회지
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• 제25권6호
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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.

• 한국초지조사료학회지
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• 제10권2호
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• pp.96-101
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• 1990

This field experiment was undertaken to find out the effect of grazing and cutting management on the forage quality and soil hardness at different legumes sown swards of the experimental field of Livestock Experiment Station in Suweon, from August 1985 to October 1988. The results obtained are as follows: 1. Crude protein, crude fat and ash contents under grazing were higher than these under cutting, but showed the reverse results in crude fiber and nitrogen free extracts contents. Average in vitro dry matter digestibility (IVDMD) under grazing (72 %) was a little higher than that under cutting (71 %). On the other hand, there was little difference among the mixtures swards in mineral contents and IVDMD. 2. The contents of Ca, P and Mg were a little high in the cutting, but K and Na contents were in gazing. Ca: P ratio in grazing (2.97) was slightly higher than that of cutting (2.94). 3. Production of energies(TDN, StE and NEL) with cutting were appeard to increase by 19.4 %, 13.5 %and 19.0 % than those of grazing, respectively. Mixtures swards including alfalfa showed more production both grazing and cutting. 4. Soil hardness in the top lOcm of soil by cattle grazing was changed from 15.5mm at startihg year to 22.6 mm after 3 years, but in cutting slightly increase from 15.5mm to 16.2mm. Generally it was low in early spring and high in autumn.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.553-556
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• 2003

End-milling have been used in the industrial world because it is very effective to the manufacture of mechanical parts with various shape. Recently the end-milling processing is needed the high-precise technique with good surface roughness and rapid time in aircraft, automobile part and molding industry. Therefore this study carried to decide the optimum cutting condition for surface roughness and rapid manufacturing time using design of experiment and ANOVA. From the results of experimentation, surface roughness have an effect on cutting direction, spindle speed and depth of cut. And then the optimum condition used Taguchi design is upward cutting in cutting direction, 600rpm in spindle speed, 240mm/min feed rate, 2mm in axial depth of cut and 0.25mm radial depth of cut. By using design of experiment, it is effectively represented shape characteristics of working surface in end-milling.

• Design & Manufacturing
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• 제13권2호
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• pp.54-59
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• 2019

CNC(Computer Numerical Control) machine tools are being used in various industrial fields such as aircraft and automobiles. The machining conditions used in the mold industry are used, and the simulation and the experiment are compared. The tool used in the experiment was carried out to increase the reliability of the simulation of the cutting machining. The program used in the 3D-FEM (finite element method) was the AdvantEdge and predicted by down-milling. The tool model is used 3D-FEM simulation by using the cutting force, temperature prediction. In this study, we carried out the verification of cutting force by using a 3-axis tool dynamometer (Kistler 9257B) system when machining the plastic mold Steel machining of NAK-80. The cutting force experiment data using on the charge amplifier (5070A) is amplified, and the 3-axis cutting force data are saved as a TDMS file using the Lab-View based program using on NI-PXIe-1062Q. The machining condition 7 was the most similar to the simulation and the experimental results. The material properties of the NAK-80 material and the simulation trends reflected in the reverse design of the tool were derived similarly to the experimental results.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 춘계학술대회 논문집
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• pp.114-118
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• 1996

Evaluation of cutting condition is one of the most important aspect to improve productivity and quality. In this study, the wear and cutting characteristics(cutting force, acoustic emission signal and surface roughness) of ceramic cutting tool for hardened die material(SKD11) were investigated by experiment. Flank wear on relief face of tool was occurred more dominant than crater wear on rake face. Experiments were performed under the various cutting condition.

• 한국공작기계학회논문집
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• 제13권6호
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• pp.1-9
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• 2004

For improvement of productivity and cutting tool lift, cutting force in end milling needs to be predicted accurately. In order to analyze cutting force, the cutting dynamics was modelled mathematically by using chip load, cutting geometry, and the relationship between cutting forces and the chip load. Specific cutting force coefficients of the cutting dynamics model were obtained by average cutting forces, tool diameter, cutting speed, fled, axial depth and radial depth of cut. The effects of the cutting conditions on the specific cutting force constants in milling were studied. The model is verified through comparisons of model predicted cutting forces with measured cutting forces obtained from machining experiments.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 봄 학술발표회 논문집
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• pp.585-591
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• 1997

The purpose of this experiment is to verify and efficiency of repair for cutting area. The result of this experiment is the fact thar the strength of compression and bending in declined by width and depth of cutting area. Deterioration of strength depends on depth to be repair area the strength of compression decreased up 50% when the repairing area is the fact that it is emerged by the increased of depth size rather than width size.