• Title/Summary/Keyword: contour analysis

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Study on the Noise Reduction in the Rotary Compressor Using BLDC Motor (BLDC 모터를 적용한 로터리 컴프레서 소음 저감에 관한 연구)

  • Kim, Jin-Soo;Lim, Kyung-Nae;Ku, Se-Jin;Lee, Jang-Woo;Jeon, Si-Moon
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.18 no.9
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    • pp.920-929
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    • 2008
  • The main noise and vibration source of the BLDC rotary compressor for air conditioner was analyzed by using the measurement of noise and vibration, noise contour, and experimental modal analysis. The source is presumed to the mechanical resonance excited by the electromagnetic attractive force of the BLDC motor. To reduce the excessive noise of the BLDC rotary compressor due to the mechanical resonance, air-gap enlargement and structural dynamic modification were applied in this paper. Its validations were conducted by the analysis of the electromagnetic attractive force which is generated by the BLDC motor and by the measurement of noise and vibration of the BLDC rotary compressor. By enlarging the length of air-gap and conducting the structural dynamic modification, the noise and vibration in the compressor was significantly improved by 4.5 dB(A) and 56 percent, respectively.

Tension Estimation of Tire using Neural Networks and DOE (신경회로망과 실험계획법을 이용한 타이어의 장력 추정)

  • Lee, Dong-Woo;Cho, Seok-Swoo
    • Journal of the Korean Society for Precision Engineering
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    • v.28 no.7
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    • pp.814-820
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    • 2011
  • It takes long time in numerical simulation because structural design for tire requires the nonlinear material property. Neural networks has been widely studied to engineering design to reduce numerical computation time. The numbers of hidden layer, hidden layer neuron and training data have been considered as the structural design variables of neural networks. In application of neural networks to optimize design, there are a few studies about arrangement method of input layer neurons. To investigate the effect of input layer neuron arrangement on neural networks, the variables of tire contour design and tension in bead area were assigned to inputs and output for neural networks respectively. Design variables arrangement in input layer were determined by main effect analysis. The number of hidden layer, the number of hidden layer neuron and the number of training data and so on have been considered as the structural design variables of neural networks. In application to optimization design problem of neural networks, there are few studies about arrangement method of input layer neurons. To investigate the effect of arrangement of input neurons on neural network learning tire contour design parameters and tension in bead area were assigned to neural input and output respectively. Design variables arrangement in input layer was determined by main effect analysis.

Intermediate Font Generation based on Shape Analysis of Hangul Glyph (한글 글립의 조형적 분석에 기반한 중간 폰트 생성)

  • Koo, Sang-Ok;Jung, Soon-Ki
    • Journal of KIISE:Computer Systems and Theory
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    • v.36 no.4
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    • pp.311-325
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    • 2009
  • This paper presents a method for analyzing Hangul glyphs with their outline fonts and obtaining intermediate fonts with two different fonts. The glyphs are represented and analyzed hierarchically such as characters, components(letters) and strokes. With the analysis results, we obtain several intermediate glyphs by morphing two different glyphs of same character. For a natural glyph contour morphing, we employ the curve morphing algorithm by weighted mean of strings. In addition, we provide four operations for transformation of glyphs with different topology. As a result, it is illustrated that the proposed Hangul glyphs morphing scheme is useful for new font generation from any exist fonts or handwritings.

An acoustical analysis of synchronous English speech using automatic intonation contour extraction (영어 동시발화의 자동 억양궤적 추출을 통한 음향 분석)

  • Yi, So Pae
    • Phonetics and Speech Sciences
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    • v.7 no.1
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    • pp.97-105
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    • 2015
  • This research mainly focuses on intonational characteristics of synchronous English speech. Intonation contours were extracted from 1,848 utterances produced in two different speaking modes (solo vs. synchronous) by 28 (12 women and 16 men) native speakers of English. Synchronous speech is found to be slower than solo speech. Women are found to speak slower than men. The effect size of speech rate caused by different speaking modes is greater than gender differences. However, there is no interaction between the two factors (speaking modes vs. gender differences) in terms of speech rate. Analysis of pitch point features has it that synchronous speech has smaller Pt (pitch point movement time), Pr (pitch point pitch range), Ps (pitch point slope) and Pd (pitch point distance) than solo speech. There is no interaction between the two factors (speaking modes vs. gender differences) in terms of pitch point features. Analysis of sentence level features reveals that synchronous speech has smaller Sr (sentence level pitch range), Ss (sentence slope), MaxNr (normalized maximum pitch) and MinNr (normalized minimum pitch) but greater Min (minimum pitch) and Sd (sentence duration) than solo speech. It is also shown that the higher the Mid (median pitch), the MaxNr and the MinNr in solo speaking mode, the more they are reduced in synchronous speaking mode. Max, Min and Mid show greater speaker discriminability than other features.

Structural Analysis of Thin-Walled, Multi-Celled Composite Blades with Elliptic Cross-Sections (다중세포로 구성된 박벽 타원형 단면 복합재료 블레이드의 구조해석)

  • 박일주;정성남
    • Composites Research
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    • v.17 no.4
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    • pp.25-31
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    • 2004
  • In this study, a refined beam analysis model has been developed for multi-celled composite blades with elliptic cross-sections. Reissner's semi-complimentary energy functional is introduced to describe the beam theory and also to deal with the mixed-nature of the formulation. The wail of elliptic sections is discretized into finite number of elements along the contour line and Gauss integration is applied to obtain the section properties. For each cell of the section, a total of four continuity conditions are used to impose proper constraints for the section. The theory is applied to single- and double-celled composite blades with elliptic cross-sections and is validated with detailed finite element analysis results.

Development of Virtual Makeup Tool based on Mobile Augmented Reality

  • Song, Mi-Young;Kim, Young-Sun
    • Journal of the Korea Society of Computer and Information
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    • v.26 no.1
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    • pp.127-133
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    • 2021
  • In this study, an augmented reality-based make-up tool was built to analyze the user's face shape based on face-type reference model data and to provide virtual makeup by providing face-type makeup. To analyze the face shape, first recognize the face from the image captured by the camera, then extract the features of the face contour area and use them as analysis properties. Next, the feature points of the extracted face contour area are normalized to compare with the contour area characteristics of each face reference model data. Face shape is predicted and analyzed using the distance difference between the feature points of the normalized contour area and the feature points of the each face-type reference model data. In augmented reality-based virtual makeup, in the image input from the camera, the face is recognized in real time to extract the features of each area of the face. Through the face-type analysis process, you can check the results of virtual makeup by providing makeup that matches the analyzed face shape. Through the proposed system, We expect cosmetics consumers to check the makeup design that suits them and have a convenient and impact on their decision to purchase cosmetics. It will also help you create an attractive self-image by applying facial makeup to your virtual self.

Lower Body Shape Classification of Chinese Males in Their 20s by Analyzing Photographic Measurement (사진측정(寫眞測定)에 의한 중국(中國) 20대(代) 남성(男性)의 하반신(下半身) 형태(形態) 분류(分類))

  • Lee, So-Young;Shim, Boo-Ja
    • Journal of Fashion Business
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    • v.11 no.1
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    • pp.61-74
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    • 2007
  • Photographic measurement was first made with the subjects of 190 males in their 20s residing in the Ningbo area, Zhejiang Province in China. In this second report, lower body shapes were classified and discriminated by using indirect measurement, measurement items, and lower body analysis. The following sums up the research: 1. The subjects were $8.85^{\circ}$ (hip breadth angle), $1.58^{\circ}$ (abdomen upper angle), $11.80^{\circ}$ (hip upper angle), and $5.12^{\circ}$ (lateral lower body posture angle). 2. The subjects of Chinese males in their 20s showed three types of lower bodies: Bow Legs & Slight Slant of Lateral Lower Body Type (30.5%)-gap between legs, curve waist-hip contour, average abdomen-hip profile, and lateral lower body posture were slightly slanted forward. Adjacent Straight Legs & Slight Slant of Lateral Lower Body Type (35.8%)-adjacent straight between legs, curve waist-hip contour, slim abdomen-hip profile, and lateral lower body posture were slightly slanted forward. Balance Legs & Large Slant of Lateral Lower Body Type (33.7%)-average between legs, straight waist-hip contour, protruding hip profile, and lateral lower body posture were largely slanted forward. 3. Eight useful variables for the categorization of the subjects' lower body types were chosen through stepwise discriminant analysis, and the hit ratio of discrimination was 97.9%.

A New EGG System Design and Speech Analysis for Quantitative Analysis of Human Glottal Vibration Patterns (성문진동 패턴의 정량적인 해석을 위한 새로운 시스템 설계와 음성분석)

  • 김종찬;이재천;김덕원;오명환;윤대희;차일환
    • Journal of Biomedical Engineering Research
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    • v.20 no.4
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    • pp.427-433
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    • 1999
  • The purpose of the study is to develop an improved pitch extraction method that can be used in a variety of speech applications such as high-puality compression and vocoding, and recognition and synthesis of speech. To do so, we develop a new electroglottograph (EGG) measurement system that is based on the four modulation-demodulation type spot electrodes for detecting the EGG signals. Then, the glottal closure instant(GCI) is determined from the EGG signals on a real-time basis. We can obtain the pitch contour using the information on the GCI. It turns out that the new pitch contour algorithm (PCA) operates more reliably as compared to the conventional speech-only-based algorithm. In addition, we study the speech source models and glottal vibratory patterns for Koreans by measuring and analyzing the diversified vibration patterns of the vocal from the EGG signals.

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Extraction of Blood Flow of Brachial Artery on Color Doppler Ultrasonography by Using 4-Directional Contour Tracking and K-Means Algorithm (4 방향 윤곽선 추적과 K-Means 알고리즘을 이용한 색조 도플러 초음파 영상에서 상환 동맥의 혈류 영역 추출)

  • Park, Joonsung;Kim, Kwang Baek
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.24 no.11
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    • pp.1411-1416
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    • 2020
  • In this paper, we propose a method of extraction analysis of blood flow area on color doppler ultrasonography by using 4-directional contour tracking and K-Means algorithm. In the proposed method, ROI is extracted and a binarization method with maximum contrast as a threshold is applied to the extracted ROI. 4-directional contour algorithm is applied to extract the trapezoid shaped region which has blood flow area of brachial artery from the binarized ROI. K-Means based quantization is then applied to accurately extract the blood flow area of brachial artery from the trapezoid shaped region. In experiment, the proposed method successfully extracts the target area in 28 out of 30 cases (93.3%) with field expert's verification. And comparison analysis of proposed K-Means based blood flow area extraction on 30 color doppler ultrasonography and brachial artery blood flow ultrasonography provided by a specialist yielded a result of 94.27% accuracy on average.

Comparative analysis on intaglio surface trueness, wear volume loss of antagonist, and fracture resistance of full-contour monolithic zirconia crown for single-visit dentistry under simulated mastication

  • Kim, Yong-Kyu;Yoon, Hyung-In;Kim, Dae-Joon;Han, Jung-Suk
    • The Journal of Advanced Prosthodontics
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    • v.14 no.3
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    • pp.173-181
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    • 2022
  • PURPOSE. This analysis aimed to evaluate the intaglio surface trueness, antagonist's wear volume loss, and fracture resistance of full-contour crowns of (Y, Nb)-stabilized fully-sintered zirconia (FSZ), 4 mol% or 5 mol% yttria-stabilized partially sintered zirconia (4YZ or 5YZ) with high-speed sintering. MATERIALS AND METHODS. A total of 42 zirconia crowns were separated into three groups: FSZ, 4YZ, and 5YZ (n = 14). The intaglio surface trueness of the crowns was evaluated at the inner surface, occlusal, margin, and axial areas and reported as root-mean-square, positive and negative average deviation. Half of the specimens were aged for 120,000 cycles in the chewing simulator, and the wear volume loss of antagonist was measured. Before and after chewing, the fracture load was measured for each group. The trueness values were analyzed with Welch's ANOVA, and the wear volume loss with the Kruskal-Wallis tests. Effect of the zirconia type and aging on fracture resistance of crowns was tested using two-way ANOVA. RESULTS. The intaglio surface trueness measured at four different areas of the crown was less than 50 ㎛, regardless of the type of zirconia. No significant P in wear volume loss of antagonists were detected among the groups (P > .05). Both the type of zirconia and aging showed statistically significant effects on fracture resistance (P < .05). CONCLUSION. The full-contour crowns of FSZ as well as 4YZ or 5YZ with high-speed sintering were clinically acceptable, in terms of intaglio surface trueness, antagonist's wear volume loss, and fracture resistance after simulated mastication.