• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.7
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• pp.928-938
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• 1997

The end winding is an important part in induction motor for thermal analysis. But there is little information on the heat transfer coefficient of that surfaces because of geometrical complexity. So our experimental object is to know the heat transfer coefficient of end winding and find the optimum design parameter of rotor fan. Carbon coated papers were used for a uniform heat generating surfaces which were easy to fabricate. The experiments of some parameters were performed as varying rotation speed of rotor fan. We obtained the local and average Nusselt number of the end winding surfaces by correcting radiation and conduction losses errors. The results showed that the average Nusselt number increased with rotor fan blade number and width but decreased with end winding length. However, the increasing limits existed in the case of rotor fan width and blade number. So optimum design value were obtained for rotor fan width and blade numbers.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2008.11a
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• pp.363-368
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• 2008

The purpose of the study is to elicite a dwelling standard for the low-income group as belong to future socially underprivileged class through an investigation of the average size of each zone in plane figures of the apartment. The investigation has been executed to 2 kinds of plane pictures of the most spread exclusive using area scale: $85m^2$ and $65m^2$, which would be a groundwork of data to harmonize with the future dwelling needs, especially those of low-income group. 312 cases were selected to be investigated about each floor space of the living room, the main room, room1, room2, and the kitchen based on wall distance, to be calculated and charted about the average and the proportion of width and depth of each zone. The investigation about how those elements effect to the overall width and depth of the apartment according to the composition and the floor space shape executed as well.

• Journal of Computing Science and Engineering
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• v.10 no.2
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• pp.39-50
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• 2016

In this paper, we present a comparative study of spatial domain features for writer identification and verification with different ink width conditions. The existing methods give high error rates, when comparing two handwritten images with different pen types. To the best of our knowledge, we are the first to design the feature with different ink width conditions. To address this problem, contour based features were extracted using a chain code method. To improve accuracy at higher levels, we considered histograms of chain code and variance in bins of histogram of chain code as features to discriminate handwriting samples. The system was trained and tested for 1,000 writers with two samples using different writing instruments. The feature performance is tested on our newly created dataset of 4,000 samples. The experimental results show that the histogram of chain code feature is good compared to other methods with false acceptance rate of 11.67%, false rejection rate of 36.70%, average error rates of 24.18%, and average verification accuracy of 75.89% on our new dataset. We also studied the effect of amount of text and dataset size on verification accuracy.

• Structural Engineering and Mechanics
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• v.20 no.1
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• pp.1-20
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• 2005

The present paper deals with the seismic response analysis and the evaluation of most likely failure modes for a water storage structure. For the stress analysis, a 3-D mathematical model has been adopted to represent the structure appropriately. The structure has been analyzed for both static and seismic loads. Seismic analysis has been carried out considering the hydrodynamic effects of the contained water. Based on the stress analyses results, the most likely failure modes viz. tensile cracking and compressive crushing of concrete for the various structural elements; caused by the seismic event have been investigated. Further an attempt has also been made to quantify the initial leakage rate and average emptying time for the structure during seismic event after evaluating the various crack parameters viz. crack-width and crack-spacing at the locations of interest. The results are presented with reference to peak ground acceleration (PGA) of the seismic event. It has been observed that, an increase in PGA would result in significant increase in stresses and crack width in the various structural members. Significant increase in initial leakage rate and decrease in average emptying time for the structure has also been observed with the increase in PGA.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.15 no.5
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• pp.65-71
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• 2006

This paper presents the robust design of gripper part for a high-speed LCD(Liquid Crystal Display) transfer system. In this paper, the $1^{st}$ DOE(Design of Experiment) is conducted to find out main-effect factors for the design of gripper part. Thirty-six analysis are performed using $ANSYS^{(R)}$ and their results are statistically analyzed using $MINITAB^{(R)}$, which shows that the factors, i.e., First-width, Second-width, Rec-width, and thickness of gripper part, are more important than other factors. The main effect plots shows that the maximum deflection and mass of gripper part are minimized by increasing First-width, Second-width, Rec-width and thickness. The $2^{nd}$ DOE is conducted to obtain RSM(Response Surface Method) equation. The CCD(Central Composite Design) technique with four factors is used. Optimum design is conducted using the RSM equation. Genetic algorithm is used for optimal design. Six sigma robust design is conducted to find out a guideline for control range of design parameter. To obtain six sigma level quality, the standard deviations of design parameters are shown to be controlled within 5% of average design value.

• Archives of Plastic Surgery
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• v.38 no.5
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• pp.674-678
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• 2011

Purpose: Straight closure line of classic Weir excision leaves visible scars and makes it difficult to precisely approximate resection margins. Hence this study introduces Park-Weir excision that effectively reduces alar width with minimal alar rim scar by 3-dimensional zigzag incision and properly controls the approximation of edges. Methods: From 2008 to 2010, 14 patients underwent Park-Weir excision, crossed wedge excision on alar rim not exceeding 5 mm in width. Each patient was photographed in the same position. Alar width and columellar height against intercanthal distance was compared preoperatively and postoperatively, using image analysis software. Results: Five patients were female and nine were male. Average follow up period was 8 month. Alar width was reduced by 50.50% to 45.96%, original alar width reduced by 8.98% without significant changes in columellar height which was reduced by 0.39%. No visible scar was reported during outpatient follow-up. Conclusion: Park-Weir excision effectively reduces alar width and corrects the flaring of alar without affecting the columellar height. Zigzag incision of Park-Weir excision leaves aesthetically more pleasant scar than straight single incision of classical Weir excision.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.17 no.1
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• pp.46-51
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• 2009

This paper presents results from field studies carried out to monitor off-target droplet movement of endosulfan insecticide applied to the Korea chestnut tree area. As a results, mean airborne drift values were recorded 25m as average from downwind of a single flight line(sample line) in mountain terrain and mean effective swath width was recorded 19.5m as average in a plain. In terms of characteristics of geography of Korea aerial application is mainly carried out in mountain terrain. The equipment, weather conditions, and appropriate aerial spray technic are required for effective aerial application. In particular, the pilot can get effective results when he only sprays with consideration of environment factors since there is much turbulence in mountain terrain. Eventually, the most effective factor of droplets drift is to estimate the local weather conditions exactly.

• Journal of Power Electronics
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• v.16 no.3
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• pp.905-914
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• 2016

A high-performance rectifier is introduced in this study. The proposed rectifier combines the conventional pulse width modulation, soft commutation, and instantaneously average line current control techniques to promote circuit performance. The voltage stresses of the main switches in the rectifier are lower than those in conventional rectifier topologies. Moreover, conduction losses of switches in the rectifier are certainly lower than those in conventional rectifier topologies because the power current flow path when the main switches are turned on includes two main power semiconductors and the power current flow path when the main switches are turned off includes one main power semiconductor. The rectifier also adopts a ZCS-PWM auxiliary circuit to derive the ZCS function for power semiconductors. Thus, the problem of switching losses and EMI can be improved. In the control strategy, the controller uses the average current control mode to achieve fixed-frequency current control with stability and low distortion. A prototype has been implemented in the laboratory to verify circuit theory.

• Journal of Fashion Business
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• v.10 no.5
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• pp.105-121
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• 2006

Body measurement was first made with the subjects of 193 males in their 20s residing in the Ningbo area, Zhejiang Province in China. In this first report, lower body shapes were classified and discriminated by using anthropometric measurement indices and lower body analysis. The following sums up the research: 1. Compared with the average values of Korean males in their 20s, the Chinese subjects were characterized with thinner waist, more flat hip, and smaller midthigh. 2. The subjects of Chinese males in their 20s showed three types of lower bodies: H-Round Type (25.91%)-thick waist-abdomen, round cross-section waist-abdomen, and small waist-hip difference. A-Trapezoid Type (34.72%)-small width of omphalion waist-abdomen, average cross-section waist-abdomen, and large waist-hip difference. A-Balance Type (39.38%)-average width of omphalion waist-abdomen, flat cross-section waist-abdomen, and large waist-hip difference. 3. Seven useful variables for the categorization of the subjects' lower body types were chosen through stepwise discriminant analysis, and the hit ratio of discrimination was 96.89%.

• Journal of Life Science
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• v.11 no.2
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• pp.159-165
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• 2001

In order to reserve abundant germplasm for breeding new corn varieties, major characteristics of ears and kernels were evaluated with a total of 210 Korean indigenous maize lines collected from various parts of Pusan City and Kynugnam Province, Korea The average ear length and ear diameter of indigenous maize lines collected was 12.52cm and 3.33 cm, respectively. The average ear weight of the maize lines was 63.70g. The ears collected from the north-west mountainous region were the heaviest, and The ears from the south coastal region were the lightest. The average kernel weight per ear was 50.54g, and the kernel weight per ear by region showed a tendency similar to the ear weight. The kernels of maize lines collected in the north-west mountainous region were the longest, and kernel width and thickness were the largest in the west plain region. 100 kernel weight and embryo weight the largest in the lines collected in the north-west mountainous region. The degree of pericarp thickness was the smallest in the lines collected in the south coastal region, and largest in the lines collected in the west plain region. Except for the correlation coefficient width and 100 kernel weight, all correlation coefficients between the characteristics of the lines showed highly significant differences.