• Title/Summary/Keyword: Shape Average

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Vibration Analysis of Loudspeaker by Using Electronic Speckle Pattern Interferometry (전자 스페클 간섭계에 의한 스피커 진동 해석)

  • 김정규;노경완;강영준;김동우
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.11a
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    • pp.356-361
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    • 1996
  • Nowadays, Electronic Speckle Pattern Interferometry is a well established measuring technique with a wide range of industrial applications, particularly in the fields of deformation measurement and vibration analysis. Comparing with holographic inteferometry, it has some attractive features, which are rapid recording and reconstruction, satisfiable automation etc. Time-average ESPI was used to provide vibration mode shape of an object whose vibration amplitude is given as a fringe pattern. However, it is not possible to determine the direction of motions of a point on the object at any given time, because time-average method does not give any information about the phase of vibration. A better technique is stroboscopic method which can measure the amplitude and phase of vibrating surface. In this paper, loudspeakers were tested by these two methods and the mode shape and amplitude of vibration were visualized. As measured results, we can assume that these techniques will be applied directly in the loudspeaker industry.

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Shape Optimization of Axial Flow Fan Blade Using Surrogate Model (대리모델을 사용한 축류송풍기 블레이드의 형상 최적화)

  • Kim, Jin-Hyuk;Choi, Jae-Ho;Kim, Kwang-Yong
    • Proceedings of the KSME Conference
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    • 2008.11b
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    • pp.2440-2443
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    • 2008
  • This paper presents a three dimensional shape optimization procedure for a low-speed axial flow fan blade with a weighted average surrogate model. Reynolds-averaged Navier-Stokes equations with shear stress transport turbulence model are discretized by finite volume approximations. Six variables from airfoil profile and lean are selected as design variables. 3D RANS solver is used to evaluate the objective functions of total pressure efficiency. Surrogate approximation models for optimization have been employed to find the optimal design of fan blade. A search algorithm is used to find the optimal design in the design space from the constructed surrogate models for the objective function. The total pressure efficiency is increased by 0.31% with the weighted average surrogate model.

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Study on Shape Distribution of Wear Particles with Histogram (히스토그램에 의한 마멸분의 형태분포에 관한 연구)

  • Cho, Yon-Sang;Moon, Sung-Dong;Park, Heung-Sik
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.32 no.11
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    • pp.963-969
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    • 2008
  • The wear particles are relative to the failure and the life of machine elements directly. But it is not laid down to calculate shape parameters of wear particle. To analyze a variation of distributed characteristics of wear particles on moving conditions, its shape parameters such as diameter and roundness were calculated the quantitative values by digital image processing, and had to be defined the effective method of using those data. Up to the present, the shape parameters have been used simply into the average values. But these values are not effective to analyze a variation of distributed characteristics of occurred wear particles on moving conditions. In this study, the relative histograms of shape parameters of wear particles were used for the purpose of analyzing the distribution of wear particles in various conditions. The results showed that the relative histogram of shape parameters can be effectively represented to study a wear mechanism.

Development of Pet Dog's Dummy (애견 더미 개발)

  • Lee, Ye-Ri;Jang, Jeong-Ah
    • Fashion & Textile Research Journal
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    • v.20 no.2
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    • pp.219-225
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    • 2018
  • The purpose of this study is to make an ideal dummy for adult Maltese with proper investigation of its character and direct measurement of dog body-shape. The results of the study are as follows; First, there were 6 factors to affect the characteristics of Maltese body in the analysis, which are size of body, leg shape, chest shape, leg thickness, body length, length between fore-legs. In the cluster analysis with the 6 factors there were two types of Maltese body. Type 1 has body characteristics with large body, thick leg, and small distance between front legs. Type 2 has average size of all factors including body size, leg thickness, and length between fore-legs. Second, type 2 was selected as a representative one to make a dummy reflected body shape of characteristics because it took 67.71% from entire considered factors and has average value in the measured size. The first dummy pattern was planned by copying the surface area of the representative body shape with the method of surgical tape. A dummy of single body with trunk and legs was made using 30's cotton cloth, polyester inside batting, compressed form PVC and metallic wire on the joint of trunk and legs to support dummy shape. The second pattern was made by correcting size difference of the pattern and adding the pattern of neck covering plate, metal magnetic button was inserted on the center of joint area of trunk and legs to make detachable legs for easy slip on and off the pet's wear.

The Perception of Desirable Body Shape in Some Middle School Students of Gyeongnam Area (경남지역 일부 중학생들의 체형 선호도 조사)

  • 김성희
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.27 no.5
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    • pp.1007-1014
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    • 1998
  • A questionnaire was administered to 850 middle school students in Jinju city and Hamyang province to asses their body shape preferences. Their mean current BMI(body mass index, Kg/㎡) in males(19.23±2.77) was higher than that in females(18.61±2.59). On the other hand, significant differences in BMI were not found between areas. The perceived desired weights for their current height were about+0.22kg(males) and -4.32kg(females) of their actual weights. In spite of the average weight group, many wished to lose weight because of their tendency to perceive themselves as overweight, especially among rural females. Their ideal body shape as perceived by them were 'normal' in males and 'a bit thin' in females, independent of the areas. As for the 'contentment' regarding their current weight and health, the most satisfied group in males were estimated average weight and slightly overweight group, respectively. While, the most satisfied group in females were estimated slightly underweight and overweight group, respectively. Their extreme slim-body preference might have its root in the lack of proper understanding of what the 'standard' body weight was.

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Automatic Prostate Segmentation in MR Images based on Active Shape Model Using Intensity Distribution and Gradient Information (MR 영상에서 밝기값 분포 및 기울기 정보를 이용한 활성형상모델 기반 전립선 자동 분할)

  • Jang, Yu-Jin;Hong, Helen
    • Journal of KIISE:Software and Applications
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    • v.37 no.2
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    • pp.110-119
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    • 2010
  • In this paper, we propose an automatic segmentation of the prostate using intensity distribution and gradient information in MR images. First, active shape model using adaptive intensity profile and multi-resolution technique is used to extract the prostate surface. Second, hole elimination using geometric information is performed to prevent the hole from occurring by converging the surface shape to the local optima. Third, the surface shape with large anatomical variation is corrected by using 2D gradient information. In this case, the corrected surface shape is often represented as rugged shape which is generated by the limited number of vertices. Thus, it is reconstructed by using surface modelling and smoothing. To evaluate our method, we performed the visual inspection, accuracy measures and processing time. For accuracy evaluation, the average distance difference and the overlapping volume ratio between automatic segmentation and manual segmentation by two radiologists are calculated. Experimental results show that the average distance difference was 0.3${\pm}$0.21mm and the overlapping volume ratio was 96.31${\pm}$2.71%. The total processing time of twenty patient data was 16 seconds on average.

Prediction of Spectral Acceleration Response Based on the Statistical Analyses of Earthquake Records in Korea (국내 지진기록의 통계적 분석에 기반한 스펙트럴 가속도 응답 예측기법)

  • Shin, Dong-Hyeon;Hong, Suk-Jae;Kim, Hyung-Joon
    • Journal of the Earthquake Engineering Society of Korea
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    • v.20 no.1
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    • pp.45-54
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    • 2016
  • This study suggests a prediction model of ground motion spectral shape considering characteristics of earthquake records in Korea. Based on the Graizer and Kalkan's prediction procedure, a spectral shape model is defined as a continuous function of period in order to improve the complex problems of the conventional models. The approximate spectral shape function is then developed with parameters such as moment magnitude, fault distance, and average shear velocity of independent variables. This paper finally determines estimator coefficients of subfunctions which explain the corelation among the independent variables using the nonlinear optimization. As a result of generating the prediction model of ground motion spectral shape, the ground motion spectral shape well estimates the response spectrum of earthquake recordings in Korea.

A Study on the Physical Characteristics of Irrigation Reservoirs in Korea (우리나라 관개용 흙댐 저수지의 외형적 제특성에 관한 연구)

  • 정두희;안병기
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.25 no.4
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    • pp.29-37
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    • 1983
  • This study was carried out not only to prepare available materials that can be utilized in basic planning of irrigation reservoirs, but also to contribute to the study on countermeasures for reasonable irrigation water development in Korea in the future, through the investigation for the structural characteristics of reservoirs and their change trend by an epoch. During this study 123 sites of sample reservoirs were analysed in their dimensions of physical constituent factors. The physical characteristics and their change trends revealed by this study are summarized as follows: 1. For the irrigation earth dam in Korea the correlation between dam volume (v) and dam height & length (H$^2$L) can be described as the formula of v=1. 434H2L~17, 300 (r=0. 933), from which embankment amount is assumed to be quickly estimated under determined dam height and length of the proposed reservoir. 2. The ratio of dam volume to dam height & length ranges approximately from 0.5 to 3 (1.7 in average), that of storage capacity to dam volume 2 to 10 (8.4 in average), that of irrigation area to full water surface area 5 to 20 (13 in average) and that of catchment area to irrigation area 2 to 5 (4 in average). Though correlation between dam volume and dam height & length is high, that between others is relatively low. 3. Average storage depth ranges approximately from 4m to l0m (6.6m in average), unit storage capacity 0. 4m to 0. 8m (0.54 in average) and shape factor of dam 5 to 20 (10.5 in average). 4. The more recently planned the reservoirs were, the less storage capacity, dam volume, full water surface and dam shape factor they have. 5. The more recently planned the reservoirs were, the larger storage depth and unit storage capacity they have.

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An Average Shape Model for Segmenting Prostate Boundary of TRUS Prostate Image (초음파 전립선 영상에서 전립선 경계 분할을 위한 평균 형상 모델)

  • Kim, Sang Bog;Chung, Joo Young;Seo, Yeong Geon
    • KIPS Transactions on Software and Data Engineering
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    • v.3 no.5
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    • pp.187-194
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    • 2014
  • Prostate cancer is a malignant tumor occurring in the prostate. Recently, the repetition rate is increasing. Image inspection method which we can check the prostate structure the most correctly is MRI(Magnetic Resonance Imaging), but it is hard to apply it to all the patients because of the cost. So, they use mostly TRUS(Transrectal Ultrasound) images acquired from prostate ultrasound inspection and which are cheap and easy to inspect the prostate in the process of treating and diagnosing the prostate cancer. Traditionally, in the hospital the doctors saw the TRUS images by their eyes and manually segmented the boundary between the prostate and nonprostate. But the manually segmenting process not only needed too much time but also had different boundaries according to the doctor. To cope the problems, some automatic segmentations of the prostate have been studied to generate the constant segmentation results and get the belief from patients. In this study, we propose an average shape model to segment the prostate boundary in TRUS prostate image. The method has 3 steps. First, it finds the probe using edge distribution. Next, it finds two straight lines connected with the probe. Finally it puts the shape model to the image using the position of the probe and straight lines.

A ROENTGENOGRAPHIC STUDY OF NORMAL PAROTID GLANDS USING ISOBARIC SIALOGRAPHY (등압타액선조영촬영법을 이용한 정상성인의 이하선에 관한 연구)

  • Ahn Hee Moon;Lee Sang Rae
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.20 no.1
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    • pp.91-102
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    • 1990
  • The aim of this study was to establish the diagnostic criteria of normal parotid glands in adults revealing the anatomical shape, its variations and the postitional relationships of the gland. Materials included 96 lateral and anterior-posterior sialograms of selected person from 23 to 28 years of age. Results were as follows: 1. The average length and lateral displacement of main duct was 48.43㎜ and l6.88㎜. The mean lumen diameter of that was 0.91㎜ in distal end and 1.40㎜ in hilar end in parotid glands. 2. The average angle of main duct to the inferior border of mandib was 34.32 degree. In configurations of main duct, modified curvilinear type was. most prevalent and followed by curvilinear, reverse sigmoid, sigmoid type. 3. The mean caliber of parotid gland was the longest in superior-inferior. 4. The interlobar ducts showed relatively well defined in all cases, its average number was 5.72. Arrangement of these ducts showed at random. Accessory lobe showed 87.5% in the all cases, its average number was 1.7. 5. There were no difference between the well and poorly defined acinar fillings in the glandular parenchyme. 6. There were no differences between right and left parotid glands in size and shape of main duct and parenchymal portion, but there were great variations in each individuals.

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