• 품질경영학회지
• /
• 제31권4호
• /
• pp.150-163
• /
• 2003

The purpose of this paper is to propose an interactive method using the concept of Signal­to­Noise (SN) ratios and cutting ranges for selecting the most preferred alternatives of Multiple­attribute Decision­Making(MADM) with the­smaller­the­better or the­larger­the­better characteristics. In this method the decision makers could make a grouping of attributes by their priorities. This research is based on the assumption of an equality between the attributes of MADM with the characteristics of Taguchi method. As a result, this interactive method could transform the characteristic value of Taguchi method into the size of SN ratios which are relatively easy to understand by decision makers.

• 동력기계공학회지
• /
• 제18권1호
• /
• pp.32-37
• /
• 2014

In this study, the optimum design process of an indoor package air-conditioner (PAC) was implemented by Taguchi method. The goal of this study is to obtain the best set condition of each control factor composing of an indoor PAC. The number of revolution of a double inlet sirocco fan installed in an indoor PAC was measured by the orthogonal array of $L_{18}(2^3{\times}3^4)$ and analysed by using the-smaller- the-better characteristic among the static characteristic analyses. As a result, the optimum condition of an indoor PAC was found as a set of when the cost of production, assembling and working conditions were considered. Moreover, the number of revolution of a double-inlet sirocco fan used for an optimum condition was reduced about 8.5% more than that of a standard condition for the target flowrate of $18.5m^3/min$.

• 한국기계가공학회지
• /
• 제11권5호
• /
• pp.29-34
• /
• 2012

This study describes the selection of optimum machining conditions for a high-hardness resin by using a large 5-axis machine. The experiments were conducted to examine the main factors that affect the surface roughness, such as the spindle speed, axial and radial depths of the cut, and pattern of the cutter path. To analyze the experiment results, the factor with the biggest impact on machining was determined using the smaller-the-better characteristic of the Taguchi method; the effectiveness of the experiment was then confirmed by verifying the selected optimum machining condition.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
• /
• pp.428-431
• /
• 2002

Recently, the study on development of electrical and electronic device is done to get miniature, high degrees of integration and efficiency by using inorganic materials. the study of Langmuir-Boldgett(LB) method that uses organic materials because of the limitation for the ultrasmall size. The structure of MIM(Metal-Insulator-Metal) device is Cr-Au/ PBLG/ Al. the number of accumulated layers are 1, 3, 5, 7, 9. The I-V characteristic of the device is measured from 0[V] to 2[V] and the characteristic of current-time of the devices. We have investigated the capacitance because PBLG system have a accumulated layers the maximum value of measured current is increased as the number of accumulated layers are decreased. The capacitor properties of a thin film is better as the distance between electrodes is smaller. The results have shown the insulating materials and could control the conductivity by accumulated layers.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2001년도 추계학술대회 논문집 전기물성,응용부문
• /
• pp.87-89
• /
• 2001

The structure of manufactured device is Cr-Au/Arachidic acid/Al, the number of accumulated layers are 13, 17 and 19. The I-V characteristic of the device is measured from -2[V] to +2[V] and the characteristic of current-time of the devices. We have investigated the capacitance because this fatty acid system have a accumulated layers. The maximum value of measured current is increased as the number of accumulated layers are decreased. The capacitor properties of a thin film is better as the distance between electrodes is smaller. The results have shown the insulating materials and could control the conductivity by accumulated layers.

• 한국전자파학회논문지
• /
• 제14권1호
• /
• pp.41-46
• /
• 2003

본 논문에서는 밀리미터 웨이브 대역의 PBG(Photonic Band Gap)를 적용한 고출력 증폭기를 설계하였다. 증폭기는 24.6 GHz∼24.75 GHz 까지의 동작대역을 가지며 증폭기의 선형성과 효율을 개선하기 위하여 PBG는 증폭기의 2차 고조파를 제거하도록 설계되었다. 또한 기존의 PBG 형태보다 저지 특성이 좋으면서도 출력 라인을 따라서 구현되는 PBG의 길이는 감소하도록 PBG를 변형하여 최적화 시켰다. 제작된 PBG는 증폭기의 2차 고조파대역에 대하여 35 dB 이상의 저지 특성을 보여준다. 증폭기는 입$.$출력 반사특성과 출력전력의 개선을 위하여 Lange Coupler를 이용한 Balanced 구조를 가지도록 설계하였다.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2002년도 추계학술대회 논문집 Vol.15
• /
• pp.362-365
• /
• 2002

This paper, experiment manufactures device of Metal/Poly-${\gamma}$ Benzyl $_D$-GlutamateOrganic Films/Metal structure using PBDG and I-V properties and C-F properties. The I-V characteristic is measured that approve voltage from 0 to +2[V] of device and the distance between electrode is larger, could know that small current flow and thin film could know that had insulation property. C-F characteristic has each other affinity between the polarization amount and frequency. Permittivity of MIM device could know by dipole that is voluntary polarization of LB film that polarization is happened. The capacitor properties of a thin film is better as the distance between electrodes is smaller.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2002년도 추계학술대회 논문집 전기물성,응용부문
• /
• pp.150-152
• /
• 2002

This paper, experiment manufactures device of Metal/Poly-$\gamma-Benzyl\;_D-Glutamate$ Organic Films/Metal structure using PBDG and I-V properties and C-F properties. The I-V characteristic is measured that approve voltage from 0 to +2[V] of device and the distance between electrode is larger, could know that small current flow and thin film could know that had insulation property. C-F characteristic has each other affinity between the polarization amount and frequency. Dielectric constant of MIM device could know by dipole that is voluntary polarization of LB film that polarization is happened. The capacitor properties of a thin film is better as the distance between electrodes is smaller.

• 한국레이저가공학회지
• /
• 제16권3호
• /
• pp.11-21
• /
• 2013

As parts are becoming more complex and smaller with the development of new materials, high-quality laser precision processing is getting the limelight. Laser enables quick processing and less deformation of materials. It also enables welding with diverse materials. In this study, the pole rod and tap for the secondary battery were laser-welded using cross and coaxial nozzles. The results of the comparative analysis of cross and coaxial nozzles according to the processing parameters showed that the coaxial nozzle had more sensitive welding characteristic to the nozzle position or pressure than the cross nozzle. This indicated that the processing parameters should be carefully determined for the welding with the coaxial nozzle. The pole rod and tap were welded together in a form of T joint to improve the output of the secondary battery, and the cross nozzle had a better welding characteristic than the coaxial nozzle.

• 한국전산유체공학회지
• /
• 제9권4호
• /
• pp.55-63
• /
• 2004

The three-dimensional Stokes flow within a staggered screw channel is obtained by using a finite volume method. The geometry is intended to mimic the single screw extruder having staggered arrangement of flights. The flow solution is then subjected to the analysis of the stirring performance. In the analysis of the stirring performance, the stretching-mapping method developed by the author is employed for calculating the materials' stretching exponents, which are to be used in quantification of the mixing effect. The numerical results Indicate that the staggered geometry gives indeed far much better stirring-performance than the standard (nonstaggered) flight geometry. It was also shown that care must be given to the selection of the basis planes for evaluating the local stretching rate, and it turns out that the best method (H-method) has its basis plane just on the half way between the past and future evolution of fluid particles subjected to the defromation. In evaluating the stretching exponent, the expansion ratio must be considered which is one of the characteristic differences of the actual three-dimensional flows from the two-dimensionmal counterparts. The larger axial pressure-difference causes in general the smaller stirring performance while the flow rate is increased. The smaller channel length also increases the stirring performance.