• Title/Summary/Keyword: criteria for measurement

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Determination of In-focus Criteria In Image Processing Method for Particle Size Measurement (입경측정을 위한 영상처리기법에서 입자 초점면 존재 판단 기준의 설정)

  • Koh, Kwang Uoong;Kim, Joo Youn;Lee, Sang Yong
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.23 no.3
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    • pp.398-407
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    • 1999
  • In the present image processing technique, the concept of the gradient indicator(GI) has been introduced to find out the depth-of-field in sizing large particles ranging from $30{\mu}m$ to $30{\mu}m$ where using of the concept of the normalized contrast value(VC) is not appropriate. The gradient indicator is defined as the ratio of the local value to the maximum possible value of the gray-level gradient in an image frame. The gradient indicator decreases with the increases of the particle size and the distance from the exact focal plane. A particle is considered to be in focus when the value of the gradient indicator at its image boundary stays above a critical value. This critical gradient indicator($GI_{critical}$) is defined as the maximum gradient indicator($GI_{max}$) subtracted by a constant ${\Delta}GI$ which is to account for the particle-size effect. In the present ca.so, the value of ${\Delta}GI$ was set to 0.28 to keep the standard deviation of the measured particles mostly within 0.1. It was also confirmed that, to find the depth-of-field for small particles(${\leq}30{\mu}m$) with the same measurement accuracy, tho concept of the critical normalized contrast($VC_{critical}$) is applicable with 85% of the maximum normalized contrast value($VC_{max}$). Finally, the depth-of-field was checked for the size range between $10{\mu}m$ and $300{\mu}m$ when the both in-focus criteria ($GI_{critical}$ and $VC_{critical}$) were adopted. The change of the depth-of-field with the particle size shows good linearity in both the VC-applicable and the GI-applicable ranges with a reasonable accuracy.

A Study on the Ultrasonic Measurement for Damage Evaluation of Power Plant Bearing (발전용 베어링 손상평가를 위한 초음파 측정 연구)

  • Lee, Sang-Guk
    • Proceedings of the KSME Conference
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    • 2004.11a
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    • pp.1727-1732
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    • 2004
  • For the purpose of monitoring by ultrasonic test of the ball bearing conditions in rotating machinery, a system for their diagnosis was developed. ultrasonic technique is used to detect abnormal conditions in the bearing system. And various data such as frequency spectrum, energy and amplitude of ultrasonic signals, and ultrasonic parameters were acquired during experiments with the simulated ball bearing system. Based on the above results and practical application for power plant, algorithms and judgement criteria for diagnosis system was established.

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Multivariable Bayesian curve-fitting under functional measurement error model

  • Hwang, Jinseub;Kim, Dal Ho
    • Journal of the Korean Data and Information Science Society
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    • v.27 no.6
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    • pp.1645-1651
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    • 2016
  • A lot of data, particularly in the medical field, contain variables that have a measurement error such as blood pressure and body mass index. On the other hand, recently smoothing methods are often used to solve a complex scientific problem. In this paper, we study a Bayesian curve-fitting under functional measurement error model. Especially, we extend our previous model by incorporating covariates free of measurement error. In this paper, we consider penalized splines for non-linear pattern. We employ a hierarchical Bayesian framework based on Markov Chain Monte Carlo methodology for fitting the model and estimating parameters. For application we use the data from the fifth wave (2012) of the Korea National Health and Nutrition Examination Survey data, a national population-based data. To examine the convergence of MCMC sampling, potential scale reduction factors are used and we also confirm a model selection criteria to check the performance.

Bayesian Curve-Fitting in Semiparametric Small Area Models with Measurement Errors

  • Hwang, Jinseub;Kim, Dal Ho
    • Communications for Statistical Applications and Methods
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    • v.22 no.4
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    • pp.349-359
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    • 2015
  • We study a semiparametric Bayesian approach to small area estimation under a nested error linear regression model with area level covariate subject to measurement error. Consideration is given to radial basis functions for the regression spline and knots on a grid of equally spaced sample quantiles of covariate with measurement errors in the nested error linear regression model setup. We conduct a hierarchical Bayesian structural measurement error model for small areas and prove the propriety of the joint posterior based on a given hierarchical Bayesian framework since some priors are defined non-informative improper priors that uses Markov Chain Monte Carlo methods to fit it. Our methodology is illustrated using numerical examples to compare possible models based on model adequacy criteria; in addition, analysis is conducted based on real data.

A Measurement Technique for Intelligent System

  • Jun, Sung-Hae
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2007.04a
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    • pp.361-363
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    • 2007
  • Using intelligent systems, many users do effectively their works. In general, the effective usages of the systems have to possess the usability and accuracy. So, we need some measurements for evaluating the performance of the criteria. But, in most cases, objective measurements for the evaluation are not. In this paper, we propose a measurement technique for objective evaluated measuring of intelligent systems using probability measure.

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Measurement Technology of Chamber Impedance for RF Matching (RF 정합 특성 개선을 위한 챔버의 임피던스 측정법)

  • 설용태;이의용;박성진
    • Journal of the Semiconductor & Display Technology
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    • v.2 no.4
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    • pp.13-17
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    • 2003
  • An adaptor is designed for chamber impedance measurement of plasma process. Copper rod, fixed board and compensation circuit are the major components of the adaptor. An adaptor can be to measure chamber impedance on time unless stopping a process and Data to measure can do the database. We can use it to a criteria data for a failure diagnosis. So developed adaptor could be used for diagnosis the plasma process chamber in semiconductor industry.

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Improvement of Vehicle Classification Method using Vehicle Height Measurement (차량높이 계측을 통한 차종분류 향상 방안 연구)

  • Oh, Ju-Sam;Jang, Kyung-Chan;Kim, Min-Sung
    • International Journal of Highway Engineering
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    • v.12 no.4
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    • pp.47-51
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    • 2010
  • A vehicle classification data is essential for traffic road planning and pavement. In this study, the vehicle height, vehicle criteria for classification applied to measure the height of the car driving has devised a way to install equipment. It is capable of measuring the vehicle height was confirmed to field experiments, the measurement system is obtained to the vehicle length and height data. In this experiment, results showed the accuracy of 88.6% compared to classification data using the discriminant function obtained from video replaying. The height of vehicle applying the classification criteria can be utilized to determine the vehicle class.

Importance of Volumetric Measurement Processes in Oncology Imaging Trials for Screening and Evaluation of Tumors as Per Response Evaluation Criteria in Solid Tumors

  • Vemuri, Ravi Chandra;Jarecha, Rudresh;Hwi, Kim Kah;Gundamaraju, Rohit;MaruthiKanth, Aripaka;Kulkarni, AravindRao;Reddy, Sundeep
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.5
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    • pp.2375-2378
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    • 2014
  • Cancer, like any disease, is a pathologic biological process. Drugs are designed to interfere with the pathologic process and should therefore also be validated using a functional screening method directed at these processes. Screening for cancers at an appropriate time and also evaluating results is also very important. Volumetric measurement helps in better screening and evaluation of tumors. Volumetry is a process of quantification of the tumors by identification (pre-cancerous or target lesion) and measurement. Volumetric image analysis allows an accurate, precise, sensitive, and medically valuable assessment of tumor response. It also helps in identifying possible outcomes such disease progression (PD) or complete response as per Response Evaluation Criteria in Solid Tumors (RECIST).

Study on Infrared Signature Variations of a Naval Ship Operated at sea Near Geoje-do Island (거제도 인근해상에서 운용되는 함정의 적외선 신호 변화 특성에 대한 연구)

  • Kil, Tae-Jun;Kim, Tae-Kuk
    • Journal of the Korea Institute of Military Science and Technology
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    • v.17 no.1
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    • pp.15-24
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    • 2014
  • It is essential to understand the infrared signature of a naval ship to survive against various missile attacks under variable environmental conditions. As guided missiles are developing to equip more accurate IR seekers, research works for countermeasure and IR stealth technology are strongly required. But challenging works are continuously suggested for predicting and analyzing IR signal status of naval ships to achieve low observable performance under various weather conditions, variable missions and developing threats. In this study, overall guidelines of setting design criteria for low observable ships are proposed by considering varying environmental conditions including daily and seasonal variations. Test and evaluation criteria for newly constructed ships for target and background temperature difference is proposed as a design criteria which can be predicted by change of condition and ship's speed. Through the proposed techniques and procedures, it is expected to establish the measurement and evaluation criteria by using temperature, IR Signal differences between the ship and the background.

Development of Internet Addiction Measurement Scales and Korean Internet Addiction Index (인터넷중독 측정도구와 한국형 인터넷중독지표의 개발)

  • Park, Jae-Sung
    • Journal of Preventive Medicine and Public Health
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    • v.38 no.3
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    • pp.298-306
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    • 2005
  • Objectives : To develop measurement scales of Internet addiction, and propose a Korean Internet Addiction Index (K-IAI) and classification criteria for Internet addiction from the threshold scores developed. Methods : The identification of the concept of 'Internet addiction' was based on the literature review. To select the scales, an exploratory factor analysis was applied. A construct validation was tested by a confirmatory factor analysis (CFA) with a structured equation model (SEM). In testing the validity of the classification criteria, ANOVA and non-recursive models with SEM were applied. Results : Out of 1,080 questionnaires distributed, 1,037 were returned,; a response rate of 96%. The Cronbach-$\alpha$ of all items was over 0.75. Using an exploratory factor analysis in the condition of a 6 factor constrain as the study model proposed, 23 of the initial 28 items were identified. In testing the discriminant and convergent validity of the selected 23 scales using CFA with SEM, the Internet addiction model explained about 93% of all variances of the data collected, and all the latent variables significantly explained the designated scales. A K-IAI was proposed using the T-scores of the sum of all factor averages. In the classification of users, the basic concept was a twostandard deviation approach of the K-IAI as the criteria of MMPI. The addiction group had a score ${\geq}70$ in the K-IAI, the pre-addiction group between ${\geq}50$ and <70, and the average user group <50. The Internet use times of the classified groups were statistically different in the ANOVA and multiple comparisons. Conclusions : The K-IAI is a reliable and valid instrument for measuring Internet addiction. Moreover, the taxonomy of the groups was also verified using various methods.