• Title/Summary/Keyword: Level sets

Search Result 883, Processing Time 0.034 seconds

Development and Evaluation of Stitching Algorithm With five Degrees of Freedom for Three-dimensional High-precision Texture of Large Surface (대면적/고정밀 3차원 표면형상의 5자유도 정합법 개발 및 평가)

  • Lee, Dong-Hyeok;Ahn, Jung-Hwa;Cho, Nham Gyoo
    • Journal of the Korean Society of Manufacturing Technology Engineers
    • /
    • v.23 no.2
    • /
    • pp.118-126
    • /
    • 2014
  • In this paper, a new method is proposed for the five-degree-of-freedom precision alignment and stitching of three-dimensional surface-profile data sets. The control parameters for correcting thealignment error are calculated from the surface profile data for overlapped areas among the adjacent measuring areas by using the "least squares method" and "maximum lag position of cross correlation function." To ensure the alignment and stitching reliability, the relationships betweenthe alignment uncertainty, overlapped area, and signal-to-noise level of the measured profile data are investigated. Based on the results of this uncertainty analysis, an appropriate size is proposed for the overlapped area according to the specimen's surface texture and noise level.

Dynamic analysis for High-speed train using acceleration value (고속철도차량의 가속도 값을 이용한 차량 동특성 분석)

  • Kim, Young-Mo;Choi, Sung-Hun;Kim, Ki-Hwan;Park, Tae-Won
    • Proceedings of the KSR Conference
    • /
    • 2007.05a
    • /
    • pp.169-174
    • /
    • 2007
  • Adopting articulated bogie system, the HSR350x and KTX have similar physical mechanical characteristic, but they show different dynamic characteristics due to different position of suspensions and those physical properties. The low level vibration frequency which effects on the ride comfort of passengers and the high level vibration frequency which is related to noise of vehicle have been measured by accelerometers mounted on Wheel sets, Bogies and Car bodies to analysis the dynamic characteristics of the High-Speed Trains. The KTX number 36 is utilized to measure the lateral and vertical acceleration value of car body, and total measurement system of HSR350x have been used to acquire acceleration data. The sampling frequency of data is 500Hz generally, but the Car body at TT2 of HSR350 has 1000Hz exceptionally.

  • PDF

Prediction of Stand Structure Dynamics for Unthinned Slash Pine Plantations

  • Lee, Young-Jin;Cho, Hyun-Je;Hong, Sung-Cheon
    • The Korean Journal of Ecology
    • /
    • v.23 no.6
    • /
    • pp.435-438
    • /
    • 2000
  • Diameter distributions describe forest stand structure information. Prediction equations for percentiles of diameter distribution and parameter recovery procedures for the Weibull distribution function based on four percentile equations were applied to develop prediction system of even-aged slash pine stand structure development in terms of the number of stems per diameter class changes. Four percentiles of the cumulative diameter distribution were predicted as a function of stand characteristics. The predicted diameter distributions were tested against the observed diameter distributions using the Kolmogorov-Smirnov two sample test at the ${\alpha}$=0.05 level. Statistically, no significant differences were detected based on the data from 236 evaluation data sets. This stand level diameter distribution prediction system will be useful in slash pine stand structure modeling and in updating forest inventories for the long-term forest management planning.

  • PDF

Clothing Purchase Behavior according to Consumer Self-Confidence (소비자 자신감에 따른 의복구매행동)

  • Jeon, Kyung-Sook
    • Journal of the Korean Home Economics Association
    • /
    • v.45 no.6
    • /
    • pp.1-9
    • /
    • 2007
  • Even though self-confidence is a personal factor of a people, it works as behavioristic factor in consumer behavior. In this study, the influence of consumer self-confidence on clothing purchase behavior was investigated. A total of 284 data sets were analyzed after collecting questionnaires from college students in Seoul using convenient sampling method. For data analysis, chi-square test, analysis of variance, reliability test and factor analysis were performed by SPSSWIN program. The results were as followed. First, the clothing purchase places were affected by the consumers' level of self-confidence. The more confident consumers preferred internet shopping and Dongdaemun market to large-scale shops. The discount stores were selected by the less confident consumers. Second, information search was one of the main reasons to visit internet shopping mall by the more confident consumers. Third, the more confident consumers showed the higher level of clothing involvement than the less confident consumers. Finally, unplanned purchases, such as pure impulse buying and reminder buying were more likely to occur by the more confident consumers with less purchase conflicts.

Heterogeneity of Variance by Sex in Postweaning Gain of Angus Calves under Different Environment Levels

  • Oikawa, T.;Hammond, K.;Tier, B.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.12 no.6
    • /
    • pp.846-849
    • /
    • 1999
  • Angus postweaning daily gain (PWDG) were analyzed to investigate heterogeneous variance by sex. A set of data (16,239 records) was divided into six sub-data sets according to level of environment. REML estimation was conducted by a multitrait model, where PWDG in each sex was treated as a separate trait. Estimates showed diversity among environmental levels, where the heritability for heifers was high in good environment but low in poor environment. The bull's estimates varied among environmental levels. The largest heterogeneity of phenotypic variance between sexes was estimated in a data set of the poor environment level. The genetic correlations between the heifer's PWDG and the bull's PWDG were high in the good environment and low in the poor environment (-0.17). The results suggest existence of genotype by sex interaction in the poor environment.

Ultrasonographic evaluation of rotator cuff leison

  • Sugimoto Katsumasa;Matsui Nobuo
    • The Academic Congress of Korean Shoulder and Elbow Society
    • /
    • 1995.03a
    • /
    • pp.46-46
    • /
    • 1995
  • We investigated the reliablity of the ultrasonography for diagnosis of rotatar cuff taers. We prepared histological sections of forty shoulder joints In match the ultrasound planes, and conducted a comparative study of tke two sets of images. hi cases of rotator cuff tear, hyperechogenic and cartilaginfication of the tear site were detected as hyperechogenic foci. On the countrary, the regions in which tendon fibers were decreased or absent showed sonolucent areas. We caluculated the echo level of rotator cuff objectively. The area of abnormal echo level and the other regions located in the same depth of the rotator cuff were defined by ultrasonic equipment. The mein difference in these two echo levels was calculated. The mean difference in patients with rotator cuff tears was larger than that in normal cases. These results indicate that ultrasonography is a useful procedure in many patients with rotator cuff lesions.

  • PDF

A Study on the Speech Intelligibility of Voice Disorder Patients according to the Level of Background Noise (배경소음의 정도에 따른 음성장애 환자 발화 명료도 연구)

  • Pyo, Hwa-Young
    • Phonetics and Speech Sciences
    • /
    • v.3 no.3
    • /
    • pp.173-179
    • /
    • 2011
  • The present study was performed to investigate the intelligibility of voice disorder patients by providing the various background noise levels. Four sets of 12-sentence-stimuli produced by 11 voice disorder patients were prepared, and 5 minute-news from radio broadcasting studio were used as a background noise. 30 listeners assigned intelligibility score of each sentence with visual analog scale. Each set of sentences was provided with 20dB, 10dB, 0dB noise (same intensity with stimuli), and, finally, with no noise. As results, as background noise level increased, intelligibility scores were lowered with statistical significance. Even though in the same severity, more loud background noise showed much lower scores than less loud noise. When 10dB noise was provided, intelligibility scores showed the biggest difference among the degree of severity.

  • PDF

Real-time Precision GPS Positioning Algorithm Based on Reconfiguration Kalman Filter (재구성기법을 이용한 칼만필터 기반의 실시간 정밀 GPS 측위기법)

  • Won, Jong-Hoon;Ko, Sun-Jun;Lee, Ja-Sung
    • Proceedings of the KIEE Conference
    • /
    • 2000.07d
    • /
    • pp.2439-2442
    • /
    • 2000
  • This paper presents a practical On-The-Fly(OTF) integer ambiguity resolution algorithm for real-time precise positioning with low cost, $L_1$ single frequency, conventional C/A code GPS receiver. A state reconfiguration scheme is adopted in the Kalman filter to deal with the variation of ambiguity states caused by varying sets of visible GPS satellites. The proposed algorithm reduces the ambiguity search space from the coarse m-level C/A code pseudorange measurements of the conventional C/A code reciever, thereby reducing the computational time. Simulation results are presented to show that the algorithm achieves a cm-level accuracy.

  • PDF

Computational Study of the Molecular Structure, Vibrational Spectra and Energetics of the OIO Cation

  • Lee, Sang-Yeon
    • Bulletin of the Korean Chemical Society
    • /
    • v.25 no.12
    • /
    • pp.1855-1858
    • /
    • 2004
  • Molecular geometries for the cationic and neutral species of OXO (X=Cl, Br, and I) are optimized using the Hartree-Fock (HF) theory, the second order Moller-Plesset perturbation theory (MP2), the density functional theory with the B3LYP hybrid functional (B3LYP), and the coupled cluster theory using single and double excitation with a perturbational treatment of triplet excitation (CCSD[T]) methods, with two basis sets of triple zeta plus polarization quality. The single point calculations for these species are performed at the CCSD(T,Full) level. The harmonic vibrational frequencies for these species are calculated at the HF, MP2, B3LYP and CCSD(T) levels. The adiabatic ionization potential for OIO is calculated to be 936.7 kJ/mol at the CCSD(T,Full) level and the correct value is estimated to be around 945.4 kJ/mol.

An examination on proper voltage operation standard for 154kV power system through demand analysis (수요분석을 통한 154kV 계통전압 유지기준 설정)

  • Lee, Ik-Jong;Lee, Sang-Joong
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
    • /
    • 2009.05a
    • /
    • pp.428-431
    • /
    • 2009
  • KPX sets up the voltage standards according to the voltage level to supply a good quality of electricity to customers. Supply voltages are divided into 4 levels - 345kV, 154kV, 22.9kV, and distribution voltage consisting of 110, 220 and 380V. In this research, we examine the optimal voltage operating level focused on 154kV system that mostly affects electricity quality, through analysing the system demand.

  • PDF