• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.8
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• pp.1452-1459
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• 2016

Compressed sensing is a signal processing technique for efficiently acquiring and reconstructing in and under Nyquist rate representation. Generally, the measurement prediction usually works well with a small block while the quality of recovery is known to be better with a large block. In order to overcome this dilemma, conventional research works use a structural measurement matrix with which compressed sensing is done in a small block size but recovery is performed in a large block size. In this way, both prediction and recovery are made to be improved at same time. However, the conventional researches did not compare the performances of the structural measurement matrix, affected by the block size. In this paper, by expanding a structural measurement matrix of conventional works, their performances are compared with different block sizes. Experimental results show that a structural measurement matrix with $4{\times}4$ Hadamard transform matrix provides superior performance in block size 4.

• Journal of Fashion Business
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• v.19 no.5
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• pp.139-156
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• 2015

The purpose of this study is to investigate various information relating to research on the dimensions of clothing used in the sale of products via the internet that used to target global SPA((Specialty Store Retailer of Private Label Apparel) brands sold in Korea. A total of 12 SPA brands including seven global SPA brands and five national. SPA brands were surveyed in this study. Brands were chosen net sales and consumer preferences the last three years. In all SPA brands, literal size designation such as S, M, L and numeric size designation such as 0, 2, 4 or 32, 34, 36 etc. were mixed, but in case of Jean, the size codes mark waist circumference were dominant. European size codes were more common in case of European brands while literal codes were more dominantly used for American size codes with in the US brands. By reviewing the measurement information of the body and product size, the product measurement methods of UNIQLO, FOREVER 21 and TOPTEN were much more accountable and excellent than other brands. However, most of the others didn't offer proper information such as pictograms or figures about measurement methods relating body sizes and product sizes. In addition, most of global SPA brands offered size conversion chart which consumers could reference, however of none of the national SPA brands offered a conversion size chart on their website. Regardless of the type of clothing, the coverage of clothing size was higher than in global SPA brands such as H&M GAP compared to national SPA brands. In particular, 8seconds did not present apparel size ranges that fit consumers' individual clothes sizes.

• Proceedings of the KWS Conference
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• 1993.05a
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• pp.132-134
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• 1993

The conventional way of molten nugget size measurement in welding process have utilized the metal-microscope by examining the micro sectioned weld specimen after micro-etching procedure. This paper proposes a new method for exact measurement of molten nugget size with the aid of the digital image processing unit and some developed software. This method proved to be convenient and precise in that resulting resolution and accuracy are as good as that of the conventional method.

• Proceedings of the Membrane Society of Korea Conference
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• 1991.10a
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• pp.4-8
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• 1991

The characterization of pore properties (mean pore size and pore size distribution) of the active layer in a UF membrane is important not only in order to obtain information about the factors affecting pore formation during membrane manufacturing but also to understand deeply the mechanism of solute and solvent transport through pores. Many methods of characterizing quantitatively the pore properties of UF membranes have been suggested in the literature: solvent and gas flow measurement, bubble point determination, electron microscopy, gas adsorption/desorption measurement, rejection measurement etc. But most of these methods involve time-consuming procedures and involve some wellknown problems and uncertainties.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.35 no.3
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• pp.129-135
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• 2012

Companies strive for quality improvement and use process data obtained through measurement process to monitor and control the process. Measurement data contain variation due to error of operator and instrument. The total variation is sum of product variation and measurement variation. Gage R&R is for repeatability and reproducibility of measurement system. Gage R&R study is usually conducted to analyze the measurement process. In performing the gage R&R study, several parameters such as the appropriate number of operators (o), sample size of parts (p), and replicate (r) are used. In this paper we propose how to determine the optimal combination of number of operators (o), sample size of parts (p), and replicates (r) considering measurement time and cost by statistical method.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.5
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• pp.209-213
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• 2021

For the human body shape information, body measurement techniques using a tape measure or image analysis are used. However, there is a demand for a method with high measurement accuracy and reproducibility while being simple. In this paper, domestic and foreign patent research related to body size measurement technology was conducted to identify the development trend of the related technology. WISDOMAIN DB was used to search for patents published in Korea, the United States, Japan, and Europe, and valid patents were derived by defining the technical scope of major and medium classifications and sub-categories. For the derived patents, patent trends by year, major applicants by country, and the status of technological fields were analyzed. In the field of body size measurement technology, the proportion of patent applications filed in Korea is high, indicating that Korea is leading the patent application in this field. Although the number of patent applications in the field of sensor-type measurement technology was not large, it has an advantage in measurement simplicity, so the development of related technology is expected to contribute to the improvement of measurement accuracy related to body composition analysis.

• Journal of the Korean Society of Visualization
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• v.2 no.1
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• pp.25-31
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• 2004

Droplet size is one of the most important parameter which controls the performance of the combustion system using liquid fuel or oxidizer. Droplet formation and its size are mainly affected by the injection velocity and ambient gas density. Recently, droplet size measurement was conducted by PDPA or Malvern particle analyzer using laser light. But at this paper image processing method was developed to measure droplet size. And its validation was investigated with reticle.

• Journal of radiological science and technology
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• v.16 no.1
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• pp.101-106
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• 1993

In order to assure safety of both patient and operator, and to provide uniform quality radiographs, it is necessary to perform periodic calibration of diagnostic X-ray equipment. A basic parameter of diagnostic equipment's and its image sharpness is the size(and shape the energy distribution) of the focal spot as viewed along the central X-ray beam. This size determines the resolution possible with the equipment and also determines the heat characteristics of an anode. A fine focus tube gives high resolution but causes high local heating of target. In past, the pin-hole and star pattern image measurement for evaluation of resolution have been widely used, but it produced blurring and inaccuracy of image. So newly inverted Ug-meter has advantage in more convenient measurement method and less out-put bias than other image measurement. The authors intended to compare measured focal size between Ug-meter and focal spot test tool, changed state from setting to now of units.

• Particle and aerosol research
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• v.9 no.3
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• pp.133-137
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• 2013

Measuring particle size distribution is one of the primary concerns in aerosol studies. For a nano-particle size distribution measurement, many scientists use a combination of a differential mobility analyzer (DMA) and a condensation particle counter (CPC) system, which is a called scanning mobility particle sizer (SMPS). Although it has a very high particle size resolution, some issues still remain. These problems include residence time between a DMA and a CPC, discontinuity of a CPC, and disturbance due to long scanning time during the precise measurement of particles. In particular, long scanning time is not adequate for measuring particle size distribution since the particle concentration is changing during the measurement. In this study, we developed radial exhaust multi-port system (REM-system) with no scanning time and high resolution to measure real-time particle size distribution. As a result of the REM-system performed using mono-disperse particle, it is expected that this system will be suitable for measuring continuously changing aerosol. If the counting efficiency of multi-condensation particle counter (M-CPC) and data inversion matrix are completed, REM-system will be a very adequate system for unsteady aerosol, which changes for SMPS scanning time.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.373-376
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• 2004

The measurement of diffraction of LCOS microdisplay with various pixel size, interpixel gap, pixel height and coatings demonstrates that pixel size is the leading factor for diffraction loss, while the role of varying pixel gap is less significant comparatively. One-dimensional diffraction simulation is found to be in good agreement with the measurement. Noticeable deviation occurs when pixel size is as small as 8um.