• 한국초전도학회:학술대회논문집
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• 한국초전도학회 2004년도 High Temperature Superconductivity Vol.XIV
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• pp.50-50
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• 2004

• 한국기계가공학회지
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• 제13권1호
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• pp.78-84
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• 2014

The rotation of a spindle unit must be accurate for high-quality machining and to improve the quality of the machine tools.Therefore, the proper measurement of the rotation accuracy and ensuring a proper analysis are very important. Separate processes are necessary because spindle errors and roundness errors associated with the test balls can both factor into the measured rotation error values. We used three methods to discern test ball errors and analyzed which could be deemed as the most proper technique in a test of the rotation accuracy of the main spindle of a machine tool.

• 품질경영학회지
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• 제25권1호
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• pp.69-79
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• 1997

We consider the semiparametric linear errors-in-variables model: yi=(${\alpha}+{\beta}ui+{\varepsilon}i$, xi=ui＋${\varepsilon}i$ i=1, …, n where (xi, yi) stands for an observation vector, (ui) denotes a set of incidental nuisance parameters, (${\alpha}$ , ${\beta}$) is a vector of regression parameters and (${\varepsilon}i$, ${\delta}i$) are mutually uncorrelated measurement errors with zero mean and finite variances but otherwise unknown distributions. On the basis of a simple small-sample low-noise a, pp.oximation, we propose a new method of comparing the mean squared errors(MSE) of the various competing estimators of the true regression parameters ((${\alpha}$ , ${\beta}$). Then we show that a class of estimators including the classical least squares estimator and the maximum likelihood estimator are consistent and first-order efficient within the class of all regular consistent estimators irrespective of type of measurement errors.

• 품질경영학회지
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• 제22권2호
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• pp.89-97
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• 1994

We consider the linear calibration model: $y_1={\alpha}+{\beta}x_i+{\sigma}{\varepsilon}_i$, i = 1, ${\cdots}$, n, $y={\alpha}+{\beta}x+{\sigma}{\varepsilon}$ where ($y_1$, ${\cdots}$, $y_n$, y) stands for an observation vector, {$x_i$} fixed design vector, (${\alpha}$, ${\beta}$) vector of regression parameters, x unknown true value of interest and {${\varepsilon}_i$}, ${\varepsilon}$ are mutually uncorrelated measurement errors with zero mean and unit variance but otherwise unknown distributions. On the basis of simple small-sample low-noise approximation, we introduce a new method of comparing the mean squared errors of the various competing estimators of the true value x for finite sample size n. Then we show that a class of estimators including the classical and the inverse estimators are consistent and first-order efficient within the class of all regular consistent estimators irrespective of type of measurement errors.

• 조명전기설비학회논문지
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• 제26권5호
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• pp.48-57
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• 2012

This paper analyzes the characteristic of gird connected photovoltaic power generation system which is available to connect the utility. Renewable energy photovoltaic power system has been linked to the system to analyze the impact of photovoltaic system. It is measured that power data for the Grid connected photovoltaic power plant with instantaneous measuring and 3-sec measuring for 7 days. Harmonic field measurements have shown that the harmonic contents of a waveform varies with time. A cumulative probability approach is the most commonly used method to solve time varying harmonics. So, it is used 50[%] cumulative probability approach. This paper provides an in depth analysis on power quality field measurement of the Grid connected photovoltaic power plant.

• 한국실내디자인학회논문집
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• 제9호
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• pp.10-17
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• 1996

With the ever-increasing important of high-speed information in society as we move towards the 21 st century. Interior design and it's working condition has been changed a great deal included a sort of each special character and make a difference against the others. It used to be find a great poles asunder of worker's safety and project quality according to the environmental dimension of interior construction field as if they should be a pleasantness or poor condition. This research aimed to improvement of environmental construction field of interior with construction engineers and particular interior labors in 4 phases as : ⅠThe preparatory phase : -Secure a Budget, Environmental safety supervisor -Fix of Design quality, Construction period. -Choice of Construction method, Sub constructing Ⅱ. Starting work phase ; -Capacity , Safety of temporary power line. -Carriage, Stock of Material -Safety of Electronic tools, -Personal protector. Ⅲ. Working period ; -Ventilation, I illumination of working place. -Measurement of environmental working condition Ⅳ.Finish working phase ; -Analysis of measurement data. -Evaluation and making up for the weak point. -Keeping data.

• 한국조경학회지
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• 제31권3호
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• pp.58-73
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• 2003

It is well known that urban environment affects climate, as we can see in the quality of bio-climate. However, climate has not been recognised properly in the urban planning process. The role it flays needs to be examined for better urban environment. The main objective of this study is to investigate the climate-ecological priority area which produces cold fresh air and thermal induced wind circulation between rural and urban areas. The objective is also to improve the quality of bio-climate and wind circulation at blocked urban areas. This paper uses the measurement and analysis method of wind direction and wind speed in order to investigate the climate-ecological priority area and cold fresh air corridor. In this study, local climate conditions i.e. wind speed, wind direction, temperature, humidity etc., were measured at nine fields and analyzed. On the basis of the climate measurement, the climate ecological priority areas were delineated; These will be assigned as climate-ecological conservation areas.

• 전기학회논문지P
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• 제59권1호
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• pp.58-63
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• 2010

In this paper, we proposed a wearable respiration measurement system with textile capacitive pressure sensor. Belt typed textile capacitive pressure sensor approach of respiration measurement, from which respiration signatures and rates can be derived in real-time for long-term monitoring, are presented. Belt typed textile capacitive pressure sensor has been developed for this measurement system. the distance change of two plates by the pressure of motion has been used for the respiration measurement in chest area. Respiration rates measured with the textile capacitive pressure sensor was compared with standard techniques on 8 human subjects. Accurate measurement of respiration rate with developed sensor system is shown. The data from the method comparison study is used to confirm theoretical estimates of change in capacitance by the distance change. The current version of respiratory rate detection system using textile capacitive pressure sensor can successfully measure respiration rate. It showed upper limit agreement of $3.7997{\times}10^{-7}$ RPM, and lower limit of agreement of $-3.8428{\times}10^{-7}$ RPM in Bland-Altman plot. From all subject, high correlation were shown(p<0.0001). The proposed measurement method could be used to monitor unconscious persons, avoiding the need to apply electrodes to the directly skin or other sensors in the correct position and to wire the subject to the monitor. Monitoring respiration using textile capacitive pressure sensor offers a promising possibility of convenient measurement of respiration rates. Especially, this technology offers a potentially inexpensive implementation that could extend applications to consumer home-healthcare and mobile-healthcare products. Further advances in the sensor design, system design and signal processing can increase the range and quality of the rate-finding, broadening the potential application areas of this technology.

• 한국정밀공학회지
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• 제18권7호
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• pp.98-105
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• 2001

The machining accuracy is affected by geometric, volumetric errors of the machine tools. To improve the product quality, we need to enhance the machining accuracy of the machine tools. To this point of view, measurement and inspection of finished part as error analysis of machine tools ahas been studied for last several decades. This paper suggests the enhancement method of machining accuracy for precision machining of high quality metal reflection mirror or optics lens, etc. In this paper, we study 1) the compensation of linear pitch error with NC controller compensation function using laser interferometer measurement, 2) the method for enhancing the accuracy of NC milling machining by modeling and compensation of volumetric error, 3) the spherical surface manufacturing by modeling and compensation of volumetric error of the machine tool, 4) the system development of OMM without detaching work piece from a bed of machine tool after working, 5) the generation of the finished part profile by OMM. Furthermore, the output of OMM is compared with that of CMM, and verified the feasibility of the measurement system.

• 정보보호학회논문지
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• 제17권6호
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• pp.19-28
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• 2007

본 논문은 지문 데이터베이스를 평가하는데 가장 큰 영향을 미치는 image quality를 측정하는 새로운 방법을 제안한다. 본 논문에서는 image quality를 측정하는 hybrid segmentation 방법을 소개하고, 다양한 지문 데이터베이스에 대해 실험한 결과를 분석한다. 개발한 방법의 객관적인 평가를 위해 NIST에서 제공하는 NFIQ 프로그램을 통해 얻은 결과와 variance와 coherence의 fusion을 이용한 hybrid segmentation 결과를 비교한다. NFIQ는 지문 영상의 품질을 정확하게 측정하지만 결과가 $1{\sim}5$로 세분화되어 있지 못한 문제점을 가지고 있다. 반면 제안하는 hybrid 방법은 NFIQ보다 더 정확하고 세분화된 평가 결과를 제공한다. 두 방법에 의해 실험한 데이터베이스들을 평가한 결과, 동일한 영상에 대해 NFIQ와 hybrid segmentation의 결과가 유사하며 지문 영상의 품질을 세분화하여 측정할 수 있는 점에서 NFIQ보다 뛰어나다고 할 수 있다.