• Tribology and Lubricants
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• v.24 no.6
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• pp.308-314
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• 2008

The thermal stress have an effect on the frictional factor such as applied load, sliding speed, sliding distance and number of ventilated disk hole. However, it is difficult to know the mutual relation of these factors on thermal stress of motorcycle break disk. For this, temperature of motorcycle break disk is measured using a disk-on-pad type friction tester with full factorial design containing above 4 elements. and the thermal stress analysis of it was carried out using with ANSYS workbench. From this study, the result was shown that the regression equation which have a trust rate of 95% for thermal stress presumption of motorcycle break disk with frictional factor was composed. It is possible to apply for another automobile parts.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.993-996
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• 2005

High speed machining(HSM) technique is widely used in the appliance, automobile part and mold industries, which has many advantages such as good quality, low cost and rapid machining time. but it also has problems like tool break, smooth tool path, and so on. In particular, small size end mill is easy to break, so it must be changed before interrupting operation. Generally, the tool life of small size end mill is effected by the milling conditions whose evaluated parameters are spindle, feedrate, and width of cut. The experiments are carried out by full factorial design of experiments using and orthogonal array. This paper shows optimal combination and mathematical model for tool life, and the analysis of variance(ANOVA) is employed to analyze the main effects and the interactions of these milling parameters and the second-order polynomial regression model with three independent variables is estimated to predict tool life by multiple regression analysis.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.2 s.179
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• pp.73-80
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• 2006

High speed machining(HSM) technique is widely used in the appliance, automobile part and mold industries, because it has many advantages such as good quality, low cost and rapid machining time. But it also has problems such as tool breakage, smooth tool path, and so on. In particular, small size end mill is easy to break, so it must be changed before interrupting operation. Generally, the tool life of small size end mill is affected by the milling conditions whose selected parameters are spindle speed, feedrate, and width of cut. The experiments were carried out by full factorial design of experiments using an orthogonal array. This paper shows optimal combination and mathematical model for tool life, Therefore, the analysis of variance(ANOVA) is employed to analyze the main effects and the interactions of these milling parameters and the second-order polynomial regression model with three independent variables is estimated to predict tool life by multiple regression analysis.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.215-216
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• 2006

The effect of manufacturing parameters on friction characteristics of motorcycle break system was studied using a disk-on-pad type friction tester. Such parameters conditions have an effect on the frictional factor such as applied load, sliding speed, and number of ventilated disk hole. However, it is difficult to know the mutual relation of these factors. In this study, the friction characteristics using design of experiment containing 3 elements were investigated for an optimal condition for the best motorcycle break system employing Full factorial design. From this study, the result was shown that the applied load in frictional factors was the most important, next to sliding speed, number of ventilated disk hole.

• Korean Chemical Engineering Research
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• v.54 no.1
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• pp.44-51
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• 2016

The powder core, conventionally fabricated from iron particles coated with insulator, showed large eddy current loss under high frequency, because of small specific resistance. To overcome the eddy current loss, the increase in the specific resistance of powder cores was needed. In this study, copper oxide coating onto electrically conductive iron particles was performed using a planetary ball mill to increase the specific resistance. Coating factors were optimized by the Response surface methodology. The independent variables were the CuO mass fraction, mill revolution number, coating time, ball size, ball mass and sample mass. The response variable was the specific resistance. The optimization of six factors by the fractional factorial design indicated that CuO mass fraction, mill revolution number, and coating time were the key factors. The levels of these three factors were selected by the three-factors full factorial design and steepest ascent method. The steepest ascent method was used to approach the optimum range for maximum specific resistance. The Box-Behnken design was finally used to analyze the response surfaces of the screened factors for further optimization. The results of the Box-Behnken design showed that the CuO mass fraction and mill revolution number were the main factors affecting the efficiency of coating process. As the CuO mass fraction increased, the specific resistance increased. In contrast, the specific resistance increased with decreasing mill revolution number. The process optimization results revealed a high agreement between the experimental and the predicted data ($Adj-R^2=0.944$). The optimized CuO mass fraction, mill revolution number, and coating time were 0.4, 200 rpm, and 15 min, respectively. The measured value of the specific resistance of the coated pellet under the optimized conditions of the maximum specific resistance was $530k{\Omega}{\cdot}cm$.

• Journal of the Semiconductor & Display Technology
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• v.12 no.1
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• pp.47-51
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• 2013

The screen printing is a process that is widely used in manufacturing process of various fields such as flexible devices, portable multimedia devices, OLED, and the solar cell. The screen printing method has been studied as a method for forming the high precision micro-pattern, making the low-cost manufacturing process and reducing cost through improvement of productivity. It is applicable to deposit and forming the pillars which are one of the core element for comprising vacuum glazing. In this paper, by using the paste of the glass frit base, the screen printing was performed. We analyzed the effect for the printing process to deposit pillar paste on the screen printing parameters by the factorial experimental design. The polynomial predicting the volume of the printed supporting pillars was drawn by using screen printing.

• Journal of the Korea Computer Industry Society
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• v.9 no.5
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• pp.223-228
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• 2008

A case study to show MS Excel's convenient and powerful functions was conducted to test hypotheses with subway data. Quantitative variables were described using descriptive menu, and qualitative variables were described using histogram menu of a MS Excel software. Relationships were tested using regression menu, differences were tested using t-test menu, and factors were tested using variance-layout menu of a Excel software. Data input, management, and statistical analysis were done successfully with only a MS Excel software.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.6 no.4
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• pp.65-70
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• 2007

In this study, we analyzed about that after design form manufacture master pattern in Rapid Prototyping-RP through design program, processes to manufacture prototype using Vacuum Casting. In Rapid Prototyping-RP, there is an en-or by shrinkage of resin and, in Vacuum Casting, there is an error by shrinkage of silicon. To select condition which shrinkage become the minimum of each process, manufactured prototype after using Full Factorial Design of Design of Experiments, We could confirm shrinkage using reverse engineering and that result came into effect ANOVA 2-way. We applied errors of each process to master pattern, and then presented the method to improve flood control precision of prototype of Vacuum Casting.

• Proceedings of the Safety Management and Science Conference
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• 2007.04a
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• pp.61-71
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• 2007

최적의 효율적이고 경쟁력 있는 물류시설을 조성하기 위해 수요업체(화주)를 대상으로 입지, 임대면적, 임대조건, 임대가격, 건물의 배치, 건물의 구조, 교통처리계획, 부대시설 등에 관한 다양한 의견을 사전에 수렴, 물류시설 건립에 반영할 필요성이 대두되고 있다. 조사를 위한 시간과 비용이 과대하게 발생하는데 이러한 비효율적인 조사를 보다 효율적으로 정리하고 더 나아가 투자자의 신속하고 정확한 의사결정을 지원하기 위해서 간단하게 몇 가지의 요소만으로 사전에 진단하고 정확한 의사결정을 할 수 있는 도구의 필요성이 대두된다. 즉, 기존에는 상기에서 언급한 '수요자 접근법'을 이용하여 진행하여 왔는데, 거점적인 측면과 시설적인 측면의 요소를 반영한 새로운 "요인비교법"을 도출하였다.

• Korean Journal of Rural Living Science
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• v.4 no.1
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• pp.13-22
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• 1993

증편 제조조건의 표준화 방법설정을 위하여 다섯가지(발효원, 가수량, 발효온도, 발효시간, 팽창제) 발효조건을 완전임의 배치법으로 시험, 유의성 검정을 하였으며, 증편의 팽화도 측정 및 팽화된 증편의 생장(증편의 부푼모양, 스폰지감의 생성여부, 기공의 균일성)에 대한 관능검사를 실시하여 다음과 같은 결론을 얻었다. 1. 팽화도에 영향을 미치는 요인으로는 발효원, 가수량, 발효온도, 발효시간 둥이었으며 Yeast 1% 보다는 탁주 또는 Yeast 2%를 사용하는 것이 그리고 3$0^{\circ}C$ 보다는 4$0^{\circ}C$에서 발효시키는 편이 발효시간의 단축효과가 있는 것 같았다. 2. 증편의 팽화가 가장 잘 이루어질 수 있는 발효조건으로는 발효원으로서 탁주를 사용하며 가수량을 75%로 하여 4$0^{\circ}C$에서 4시간 발효시킨 후 성형하여 제조하는 것이었다. 3. 증편 성장에 대한 기호도에 영향을 미치는 발효조건으로는 가수량, 발효온도, 발효시간, 팽창제 둥이었으며 가수량에 관계없이 팽창제를 첨가하여 제조하는 것이 좋고 가수량이 낮을수록 발효시간을 길게하는 편이 나을듯 하다. 4. 증편 성장에 대한 기호도가 가장 높은 증편 제조조건으로는 발효원을 Yeast 1%를 사용하고 반죽의 팽창을 돕기 위해 베이킹파우더 1%를 첨가하며 4$0^{\circ}C$에서 4시간 발효시킨 후 성형하여 찌는 것이었다.