• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.31 no.5
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• pp.365-373
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• 2013

Tile caching technology is a commonly used method that optimizes the delivery of map imagery across the internet in modern WebGIS systems. However the poor performance of the map tile cache update is one of the major causes that hamper the wider use of this technique for datasets with frequent updates. In this paper, we introduce a new algorithm, namely, Partial Area Cache Update (PACU) that significantly minimizes redundant update of map tiles where the update frequency of source map data is very large. The performance of our algorithm is verified with the cadastral map data of Pyeongtaek of Gyeonggi Province, where approximately 3,100 changes occur in a day among the 331,594 parcels. The experiment results show that the performance of the PACU algorithm is 6.6 times faster than the ESRI ArcGIS SERVER$^{(r)}$. This algorithm significantly contributes in solving the frequent update problem and enable Web Map Tile Services for data that requires frequent update.

• Clinical and Experimental Reproductive Medicine
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• v.37 no.2
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• pp.173-179
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• 2010

The antiestrogen tamoxifen is currently the most commonly used adjuvant treatment of breast cancer with antiestrogenic effect on mammary tissue. However, it is also associated with endometrial abnormalities, including hyperplasia, polyps, carcinoma, mostly interpreted as evidence of estrogenic effect on the endometrium. Previously, tamoxifen-associated polyp in breast cancer has been reported in the literature. Most studies had a long follow-up period and tamoxifen-associated polyp developed more than 1 year after tamoxifen treatment. In this case, we report an unusual case of rapid growing and multiple endometrial polyps that were developed only after 3 months' tamoxifen treatment in a postmenopausal breast cancer patient who received quadrant mastectomy with a brief review of literature.

• Clean Technology
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• v.25 no.2
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• pp.147-152
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• 2019

Electrostatic precipitator that shows a good performance for the removal of particulate matter is important for controlling emissions from industrial facilities and power plants. The efficiency of the electrostatic precipitator on the removal of particulate matter is highly affected by the flow pattern inside the electrostatic precipitator. A number of studies have been conducted to obtain uniform flow distribution inside electrostatic precipitators. An electrostatic precipitator (ESP) with a length of 3.5 m and a height of 0.875 m was designed and installed in this study. The ESP included an inlet duct, diffuser, body, and contractor. Three perforated plates were installed in the diffuser of the ESP. Five pitot tubes were installed vertically and used to measure flow distribution in the cross section of the ESP body. Root mean square deviation value (RMS%) was used to examine the flow distribution inside the ESP when the perforated plates were installed in the diffuser. Flow distribution was also investigated in relation to the porosity of the perforated plate. The results showed that the perforated plates improved greatly the flow distribution inside the electrostatic precipitator. In addition, the most uniform flow distribution was found with 40%, 50%, and 50% porous perforated plates located from the inlet of the diffuser.

• The Journal of Korean Academy of Sensory Integration
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• v.17 no.1
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• pp.19-29
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• 2019

Objective : The aim of this study was to verify validity of the Activity Participation Assessment for school-age children. Methods : A questionnaire consisting of 30 items from the APA, 75 items from the PACS, and 55 items from the CAPE was administered to elementary school students. A total of 207 questionnaires were analyzed. Confirmatory factor analysis was performed to confirm the construct validity of the APA. Convergence validity and discriminant validity were verified with the average variance extracted (AVE) and the square of the correlation coefficient. The discriminant validity was the Pearson correlation coefficient of the APA, PACS, and CAPE. Results : The results of the analysis were as follows: 1) For construct validity, the goodness of fit of the modified hierarchical second-order factor model was found to be appropriate (p < .001), 2) For convergent validity, the AVE was higher than .50 for all latent variables, 3) For discriminant validity, the AVE of the latent variable was greater than the square of the correlation coefficient (0.239), 4) For concurrent validity, the correlation between the total sum of the APA and PACS scores showed a positive correlation in all domains, and the correlation coefficient ranged from .303 to .647 at a statistically significant level (p < .01), 5) The correlation coefficient between the total sum of the APA and CAPE scores was .490 for recreational activities, .329 for physical activities, .571 for social activities, .401 for skill-based activities, and .390 for self-improvement activities. All domains showed a positive correlation, and were statistically significant (p < .01). Conclusion : APA can be used as a valid assessment tool to measure the participation of school aged children.

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.3
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• pp.293-299
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• 2022

Recently, various stakeholder are interested in microplastic to cause pollution of the marine's ecosystem and effort to conduct study of product's life cycle to reduce pollution of marine's ecosystem. The micorplastic refer to materials of the nano- to micro- sized units and it can be classified into primary and secondary. The primary microplastic mean the manufactured for use in the specific field such as the microbead of the cosmetic or cleanser. also, secondary mean the unintentionally generated during use of the product such as the textile crumb by the doing the laundry. Tire and Road Wear Particles(TRWPs) are also defined as secondary microplastic. Typically, TRWPs are created by friction between the tread compound's rubber of the tire and the surface of the road du ring the driving cars. Most of the generated TRWPs exist on the roadside and some of them were carried to marine by the rainwater. In this study, we perform the quantitative analysis of the TRWPs existed in fine dust at the roadside. So, we collected the dust from the roadside in Chungcheongnam-do's C site with a movement of 1,300 cars per the hour. The collected samples were separated according to size and density. And shape analysis was performed using the Scanning Electron Microscope(SEM). We were possible to discover a lot of TRWPs at the fine dust of the 100 ± 20 ㎛. And we analysis it u sing the Thermo Gravimetric Analysis(TGA) and Gas Chromatography/Mass Spectrometer(GC/MS) for the quantitative components from the tire. As a result, it was confirmed that TRWPs generated from the roadside fine dust were included the 0.21 %, and the tire and road components in the generated TRWPs consisted of the 3:7 ratio.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.2
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• pp.115-121
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• 2002

This report summarized the static test of the rudder system for the KTX-1 basic trainer. The test loads are applied up to the limit and ultimate loads in a stepping sequence. Test loads and test results matt the strength and stiffness requirements of the rudder control system.. Using #004 full scale structure test airframe.

• Proceedings of the Korea Contents Association Conference
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• 2003.11a
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• pp.290-297
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• 2003

A time-series database is a set of data sequences, each of which is a list of changing values corresponding to an object. Subsequence matching under time warping is defined as an operation that finds such subsequences whose time warping distance to a given query sequence are below a tolerance from a time-series database. In this paper, we first point out the characteristics of the previous methods for time-series sequence matching under time warping, and then discuss the approaches for applying them to whole matching as well as subsequence matching. Also, we perform quantitative performance evaluation via a series of experiments with real-life data. There have not been such researches in the literature that compare the performances of all the previous methods of subsequence matching under time warping. Thus, our results would be used as a good reference for showing their relative performances.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.05a
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• pp.386-391
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• 2000

Due to its characteristics of acoustic wave energy absorption, punched structures are generally applied on the wall of anechoic room. When the acoustic wave propagates through the punched plates, its energy dissipates into thermal energy by flow separation induced from the viscosity of acoustic media. The acoustic pressure difference between the for-side and the aft-side of punched plate ran be represented by the sum of drag term proportional to square of velocity and inertia term proportional to acceleration. The way to get the coefficients of the terms by an experiment or relatively simple calculation is introduced.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.549-552
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• 2015

The Korean government establishes a strategy to develop the Busan New Port as a world ranking two transit-oriented port. This paper aims at presenting an efficient Inter-Terminal Transportation system in the Busan New Port as a method of achieving the government strategy. It proposes four systems to treat Inter-Terminal Transportation in the port; Double stack Multiple Trailer System (DMTS) Rail-based transportation system, Private road for Inter-Terminal Transportation, and platform for Inter-Terminal Transportation. This is shown to highly potential for efficient Inter-Terminal Transportation in the port.

• The Transactions of the Korean Institute of Power Electronics
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• v.10 no.1
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• pp.38-44
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• 2005

In a voltage source inverter, the dead time is necessary to prevent short circuits in the dc link. The dead time effect appears as a distortion of output voltages and currents. In recent years, the dead time compensation methods have been investigated in many literatures. This paper presents not the dead time compensation by sensing and calculation but the dead time elimination. The proposed inverter system doesn't need to sense load current and to calculate dead time. Adding some transformers to each leg, dead times in the inverter system are eliminated automatically. The proposed method is analyzed on each mode and verified through simulation results.