• Journal of the Korean Society for Precision Engineering
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• v.22 no.6 s.171
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• pp.144-151
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• 2005

Spin coater is regarded as a major module rotating at high speed to be used build up polymer resin thin film layer fur bonding process of GaAs wafer. This module is consisted of spin unit for spreading uniformly, align device, resin spreading nozzle and et. al. Specially, spin unit which is a component of module can cause to vibrate and finally affect to the uniformity of polymer resin film layer. For the stability prediction of rotation velocity and uniformity of polymer resin film layer, it is very important to understand the dynamic characteristics of assembled spin coater module and the dynamic response mode resulted from rotation behavior of spin chuck. In this paper, stress concentration mode and the deformed shape of spin chuck generated due to angular acceleration process are presented using analytical method for evaluation of structural safety according to the revolution speed variation of spin unit. And also, deformation form of GaAs wafer due to dynamic behavior of spin chuck is presented fur the comparison of former simulated results.

• Journal of Fashion Business
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• v.9 no.5
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• pp.1-14
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• 2005

The purpose of this study was to analysis the perception of men's wear brands (Intermezzo and Rogatis), for developing the possibility & strategy of the nichi-market in men's wear market for the apparel marketers and manufactures. For this study, the data obtained from 312 respondents were analyzed by descriptive statistics, ANOVA. The results from the study were as follow ; The perception of the 2 brand images revealed that Intermezzo accounted for 79.8% of the frequencies, and Rogatis accounted for 99%. Also, results revealed the total evaluation of Intermezzo accounted for 3.86 of the mean rated on 5 point Likert-type scales in the 9 features, and Rogatis accounted for 3.28. And then, results revealed that there were signifiant differences in 2 cluster of Rogatis that the purchasing cluster accounted for 3.46 of the mean, and the perceiving cluster accounted for 3.07. The brand images of Intermezzo and Rogatis were evaluated and rated on 5 point Likert-type scales of 17 pair adjectives. As a results, the image characteristic with Intermezzo was considered with more dynamic, trendy than the image characteristic with Rogatis. Also, results revealed that The Image with Intermezzo was considered with urban, lively, chic, modern, and sophsticated image-features, and the Image with Rogatis were evaluated mannish, urban, sophsticated, luxury, and static image-features.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.1
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• pp.33-39
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• 2018

This study performed experimental validation of the hysteretic steel slit damper's basic and dependent characteristics, which should be considered for the design. The basic characteristic of the steel slit damper is used for determining design properties of non-linear analysis, such as yielding strength, yielding displacement, elastic stiffness and post-yielding stiffness. In order to evaluate dependent characteristics of the hysteretic steel slit damper, repeated deformation capacity with respect to the displacement, velocity and aspect ratio of the damper was evaluated. In this study, steel slit damper, which is widely used in Korea, was considered. The slit dampers with 55kN and 240kN of yielding strength were produced and tested. It was concluded that the slit damper's hysteresis behavior was affected by the dependent characteristics: displacement, velocity and aspect ratio. In other words, the steel slit damper's behavior was stable within limit displacement, and aspect ratio of the strut affected repeated deformation capacity of the damper subjected to large deformation. In addition, it was observed that the repeated deformation capacity abruptly decreased at the high speed range (${\geq}60mm/sec$). Furthermore, the experimental results were evaluated with the criterion of the damping device specified in ASCE7-10.

• Wind and Structures
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• v.32 no.2
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• pp.81-87
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• 2021

The aim of the current study is to compare the performance of large 2 MW and 3 MW wind turbines operating on existing onshore wind farms using Blade Element Momentum (BEM) theory and Angular Momentum (AM) theory and illustrate the performance characteristic curves of the turbines as a function of wind speed (U∞). To achieve this, the measurement data obtained from two different Wind Energy Power Plants (WEPPs) located in the Hatay region of Turkey was used. Two different horizontal-axis wind turbines with capacities of 2 MW and 3 MW were selected for evaluation and comparison. The hub-height wind speed (UD), turbine power output (P), atmospheric air temperature (Tatm) and turbine rotational speed (Ω) data were used in the evaluation of the turbine performance characteristics. Curves of turbine power output (P), axial flow induction factor (a), turbine rotational speed (Ω), turbine power coefficient (CP), blade tip speed ratio (λ), thrust force coefficient (CT) and thrust force (T) as a function of U∞ were obtained for the 2 MW and 3 MW wind turbines and these characteristic curves were compared. Results revealed that, for the same wind speed conditions, the higher-capacity wind turbine (3 MW) was operating at higher turbine power coefficient rates, while rotating at lower rotational speed ratios than the lower-capacity wind turbine (2 MW).

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.12
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• pp.1793-1802
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• 2013

Various approaches for sound source segregation have been proposed. Among these approaches, frequency domain binaural model(FDBM) has the advantages of low computational load and effective howling cancellation. A binaural hearing assistance system based on FDBM has been proposed. This system can enhance desired signal based on the directivity information. Although FDBM has been evaluated in terms of signal-to-noise ratio (SNR) and coherence function, the evaluation results do not always agree with the human impressions. These evaluation methods provide physical measures, and do not take account of perceptual aspect of human being. Considering a binaural hearing assistance system as a one of major applications, the quality of segregated sound should keep level enough. In the paper, signal segregation performance by means of FDBM is evaluated by three objective methods, i.e., SNR, coherence and Perceptual Evaluation of Speech Quality(PESQ), to discuss the characteristic of FDBM on the sound source segregation performance. The simulation's evaluation results show that FDBM improves the quality of the left and right channel signals to an equivalent level. And the results suggest the possibility that PESQ provides a more useful measure than SNR and coherence in terms of the segregation performance of FDBM. The evaluation results by PESQ show the effects from segregation parameters and indicate appropriate parameters under the conditions. In the paper, signal segregation performance by means of FDBM is evaluated by three objective methods, i.e., SNR, coherence and PESQ, to discuss the characteristic of FDBM on the sound source segregation performance. The simulation's evaluation results show that FDBM improves the quality of the left and right channel signals to an equivalent level. And the results suggest the possibility that PESQ provides a more useful measure than SNR and coherence in terms of the segregation performance of FDBM. The evaluation results by PESQ show the effects from segregation parameters and indicate appropriate parameters under the conditions.

• Journal of the Korea Fashion and Costume Design Association
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• v.19 no.1
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• pp.91-105
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• 2017

A literature review and survey were conducted regarding the silhouette changes in bell bottom pants and the overall visual evaluation in accordance with the changes. The survey was disseminated from December 2015 to January 2016 to 245 women in their 20s living in Busan. The variables used for the silhouette changes in bell bottom pants were the volume of flare and the flare's starting point, and 20 pairs of terms were selected for visual evaluation. The results of the study are as follows: 1. Visual evaluations according to the volume of flare in bell bottoms indicated that females in their 20s appraised pants with a flare volume of 54 cm close to a straight silhouette and flare volume of 62 cm (recognized clearly as characteristic of bell bottom pants) to be more attractive and sophisticated than pants with flare volumes of 70 cm and 78 cm. 2.Visual evaluations according to the starting point of the flare in bell bottom pants showed that women appraised their legs as looking thinner when the flare started near the thighs. In a vertical visual evaluation, women appraised that their legs looked longer when the flare started near the knees and pants fit tightly around them. 3.The analysis of silhouette factors affecting the visual evaluation of bell bottom pants indicated that the volume of flare has more effect visually than the starting point of the flare.

• Journal of Power System Engineering
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• v.14 no.4
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• pp.63-67
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• 2010

This paper introduces the eddy current signal characteristic of magnetic and non-magnetic gas turbine rotor. In the past, Magnetic particle inspection method was used in magnetic material for qualitative defect evaluation and the ultrasonic test method was used for quantitative evaluation. Nowadays, eddy current method is used in magnetic gas turbine rotor inspection due to advanced sensor design technology. We are studying on the magnetic gas turbine rotor by using eddy current method. We prepared diverse depth specimens made by magnetic and non-magnetic materials. We select optimum frequency according to material standard penetration data and experiment results. We got the signal on magnetic and non-magnetic material about 0.2 mm, 05 mm, 1.0 mm, 1.5 mm 2.0 mm and 2.5 mm depth defects and compare the signal amplitude and signal trend according to defect depth and frequency. The results show that signal amplitudes of magnetic are bigger than non-magnetic material and the trends are similar on every defect depth and frequency. The detection and resolution capabilities of eddy current are more effective in magnetic material than in non-magnetic materials. So, the eddy current method is effective inspection method on magnetic gas turbine rotor. And it has the merits of time saving and simple procedure by elimination of the ultrasonic inspection in traditional inspection method.

• Journal of Korean Society of Rural Planning
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• v.18 no.1
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• pp.9-15
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• 2012

This study used GIS method for the characteristic analysis of farmstead location in study area. The present study surveyed the coordinates of location for 76 livestock farmsteads with big size in rural areas within city of Cheonan. Based on the surveyed data, this study analyzed the spatial characteristics of location for the farmsteads by using both new evaluation criteria and their corresponding GIS (geographic information system) layers developed in this research. The criteria consist of six factors, which are 2 geographic factors for slope(SLO) and aspect(ASP) of earth surface, 3 accessability factors for distance from water area(DWA), road(DRO), and built-up area(DBA), including type of landuse(TLA). In the analysis results of six criteria using the grid funcations of GIS, the highest distributed ratios of the farmsteads per criterion were found at the lower slope area less then 2% in SLO, the area with south and south-east direction in ASP, the area with distance between 500m and 1,000m in both DWA and DRO, the area within 500m in DWA, and the paddy and upland area in TLA. As new finding of this study, these analysis results seemed that the farmsteads have been located at the better places with the priority to build and manage conveniently and economically.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.5
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• pp.1320-1329
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• 1990

A static performance tester for a torque rod assembly was developed to evaluate the three characteristics of the rod rubber bushing : radial spring characteristic, thrust spring characteristic, and rotational torque characteristic. Among the various schemes considered in the conceptual design stage, the final versatile type was determined to perform three different tests in one machine. The performance testing machine carried out radial spring test, thrust spring test, and torque test of the torque rod assembly. Static performance of the torque rod assembly was evaluated with the tester developed and fatigue strength of the assembly was also tested with the servo-hydraulic structural fatigue testing machine. The life of the component was found to be related with the rubber quality and adhesionability between the rubber and the steel rod. The optimum rubber hardness was experimentally found by changing the chemical compositions of rubber, and the adhesion was improved by optimizing the shape of the outer section of a the rubber, this study ensured the development of a reliable torque rod assembly.

• The Journal of the Korea Contents Association
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• v.15 no.10
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• pp.362-373
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• 2015

This study analysed the effectiveness of aluminium(Al) filter in the added compound filtration for the removal of characteristic radiation from high atomic number material by DQE and image evaluation. 1mm Al was applied to each 0.1, 0.2, 0.3 mm copper and befere and after use were evaluated. Beam quality and DQE were tested by IEC regulations and image quality was evaluated by PSNR, MAE, MSE, CNR, SNR and qualitative analysis was performed by 7 items for resolution and contrast from chest x-ray criteria of national cancer checkup. MTF 10 and 50% were the same by 4.6, 2.54 cycle/mm and NPS, DQE, PSNR MAE, MSE, CNR, SNR and qualitative analysis were all the same or slightly better when Al was not used. PSNR is over 30dB and all significant and at the qualitative analysis, the p-value of t-test was over 0.05. The DQE and image quality evaluation have little difference between before and after use of Al filter and it is effective to use the Al filter for the reduction of skin dose by removal of characteristic radiation.