• Journal of Sericultural and Entomological Science
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• v.37 no.2
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• pp.191-196
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• 1995

The aim of the present work is to investigate the level of faults present in tussah silk yarn as detected on an Uster instrument for four different varieties of commercially available tussah(tasar) silk yarns. The structure of these faults were analysed further so as to understand the mechanism and source of their generation.

• Proceedings of the Optical Society of Korea Conference
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• 2009.10a
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• pp.255-267
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• 2009

PDP용 형광체는 소성 후 입자간 결합부족으로 인한 탈락현상 및 셀 결함 불량과 Red, Green, Blue 간 유전율 불일치로 인한 방전불량 현상 등의 문제점을 안고 있다. PDP용 형광체의 소성 후 입자간의 결합력을 증진시키기 위하여 frit을 조제로 첨가하였고, 이에 따른 기계적, 전기적, 광학적 특성의 변화를 조사하였다. 사용된 frit은 자체 소결시 무색의 투명하고 ZnO-$B_2O_3-SiO_2-Al_2O_3$계 비정질 세라믹 재료이며, 연화점은 $499.78^{\circ}C$이다. 형광체 중량의 3${\sim}$20wt% 범위에서 frit의 첨가량 변화에 따른 영향을 조사하였다. Frit의 첨가량이 증가할수록 경도가 증진 되었고, 5wt% 미만 함유될 경우 Red, Green, Blue 형광체 모두 유전율 조절 효과가 미약하였다. Red 형광체는 frit함량이 3wt% 이상 함유되면 휘도가 90% 미만으로 감소하였고, Green과 Blue는 frit 함량이 10wt%이상 함유되면 확연하게 휘도가 감소 하였다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1992.04a
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• pp.274-278
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• 1992

냉간압연기술의 발달로 냉간압연기도 매우 다양하게 발달되었으며 냉간압연의 원자재인 열간압연재의 종류도 다양하다. 최근 열간압연가공시 회수율이 높은 연속주조재(Continuous casting strip)인 CC 재가 종전의 가공과정이 복잡하며 불량율이 높은 Ingot주조재(Ingot casting strip)인 IC 재 보다 생산비율이 점차 증대되어 냉간압연재료의 주종을 차지하고있다. CC재는 냉간압연가공시 IC재에 비해 Work roll 조도저하가 현저하게 크기 때문에 슬립(Slip)과 채팅(Charttering) 현상 등이 발생하여 압연가공성이 불안정 하게 되어 Work roll과 판표면에 손상이 생기게 되고, 압연가공시 Roll 사고 등의 문제가 발생하므로 Roll 마멸의 정도를 파악하여 Roll을 효과적으로 관리하므로써 Work roll과 판표면의 슬립현상 및 채터 링현상 등을 방지할 수 있다.

• Journal of Korean Society for Quality Management
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• v.5 no.2
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• pp.21-28
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• 1977

• Journal of Nutrition and Health
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• v.18 no.3
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• pp.225-233
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• 1985

The purpose of this study is to find out the factors affecting the dietary quality of adolescence through a random sampling of 798 girls, from 13 to 19 years of age in Chung-Nam province area. This survey was conducted from Febril 6 to 16, 1985. The results can be summarized as follows 1) The mean dietary score of nutrient adequacy of subjects was 11.93 out of possible 17, which showed that all nutrients intake might be lower than the R.D.A 2) The mean age of subjects was higher in the poorer dietary groups(P<0.01). 3) In the better dietary groups, the subjects were more satisfied with their present body shape, and the ratio of over weight was lower(P<0.01). 4) In the better dietary groups, the ratio of meals missed and meals performed irregularly was lower(P<0.01). 5) The preference of protein-food group was higher in the better dietary groups(P<0.01). 6) In the better dietary groups, the frequency of snacks and instant foods was higher(P<0.01).

• Journal of Preventive Medicine and Public Health
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• v.33 no.3
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• pp.285-298
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• 2000

Objectives : To investigate the positive rate of Helicobacter pylori in patients with dyspepsia; medical compliance and related factors; the eradication rate a year after screening and related factors; the relationship between the eradication of Helicobacter pylori and the improvement of symptoms; and the estimated cost of three alternative approaches to treat Helicobacter pylori in the community. Methods : A total of 510 subjects with dyspeptic symptoms were selected and given the serological test in March 1998. The subjects were all adults over 30 years of age residing in Kyongju city. Results : Of the 510 selected subjects, 375 (73.5%) subjects proved positive for Helicobacter pylori on serological testing. Of these 304 (81.1%) who consented to an endoscopic examination, underwent a Campylobacter-like organism (CLO) test. Of these 304 subjects, 204 (67.1%), who had positive CLO test results, were given the triple therapy - tripotassium dicitrato bismuthate, amoxicillin, and metronidazole. To determine the eradication rate of Helicobacter pylori, 181 (88.1%) out of the 204 subjects who were given the triple therapy completed a follow-up urea breath test one year later. Of these, the Helicobacter pylori of 87(48.1%) subjects was eradicated. Among the 122 subjects who were medication compliant, the Helicobacter pylori eradication rate was 57.4% (70 subjects), while the eradication rates was only 28.8% (17subjects) in the non-compliant group. The Helicobacter pylori eradication was significantly related to compliance (p<0.01), but not to other characteristics and habits. The symptom improvement rate tended to be higher 62.1%), in the Helicobacter pylori eradicated group than in the non-eradicated group (59.6%). Conclusions : When the advantages and disadvantages of each alternative treatment were considered in the light of cost, antibiotic tolerance and the number of patients to be treated, alternative II was favorable in terms of cost. Alternative III was favorable in terms of the number of patients to be treated, antibiotic tolerance and early detection of gastric cancer. Further long-term research analyzing the cost-benefit and cost-effectiveness of each treatment will be needed as supporting material in creating new policies.

• Journal of Korea Society of Industrial Information Systems
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• v.23 no.1
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• pp.87-96
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• 2018

In this paper, we propose a method to determine whether there is a defect by using the similarity between ROIs (Region of Interest) of the standard image and ROIs of the image which is corrected in position and rotation after capturing the vehicle headlight. The degree of similarity is determined by the template matching based on the histogram of image, which is a some modification of the method provided by OpenCV where template matching is performed on the raw image not the histogram. The proposed method is compared with the basic method of OpenCV for performance analysis. As a result of the analysis, it was found that the proposed method showed better performance than the OpenCV method, showing the accuracy close to 100%.

• Journal of KIISE:Software and Applications
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• v.34 no.11
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• pp.953-960
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• 2007

To correctly detect muras, visual defects in TFT-LCD panels, image distortion occurring on the profess of capturing panels should be corrected. In general vision systems, there are several known methods to restore the observed image. However, the vignetting effect particularly shown only in panel images cannot be easily restored through traditional methods because it is combined with background non-uniformity due to the unique characteristic of panel. To increase the reliability of image restoration, the vignetting effect should be properly corrected after being separated from image background. Therefore, in this paper we present a new method to analyze and correct the vignetting effect of panel images using principal component analysis. Experimental results for a total of 175 test images showed that the average contrast error of the muras in the distorted images was reduced from 37% to 11% and the mura misidentification rate was decreased from 14.8% to 2.2% by image restoration.

• Journal of the Korea Convergence Society
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• v.13 no.2
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• pp.249-255
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• 2022

This study proposed an analysis framework for real-time prediction of CNC processing defects using machine learning-based models that are recently attracting attention as processing defect prediction methods, and applied it to CNC machines. Analysis shows that the XGBoost, CatBoost, and LightGBM models have the same best accuracy, precision, recall, F1 score, and AUC, of which the LightGBM model took the shortest execution time. This short run time has practical advantages such as reducing actual system deployment costs, reducing the probability of CNC machine damage due to rapid prediction of defects, and increasing overall CNC machine utilization, confirming that the LightGBM model is the most effective machine learning model for CNC machines with only basic sensors installed. In addition, it was confirmed that classification performance was maximized when an ensemble model consisting of LightGBM, ExtraTrees, k-Nearest Neighbors, and logistic regression models was applied in situations where there are no restrictions on execution time and computing power.

• Asian Journal of Turfgrass Science
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• v.26 no.2
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• pp.129-134
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• 2012

Research was focused on the improvement of poor drainage problems on golf course fairway which had not been performed soil test or properly amended during the course construction. The analysis of the drainage problem basically was caused by a deterioration of soil physical properties by the top layer compaction. The soil hardness reached about 3,000 Kpa around 5~6 cm of soil profile. The slow infiltration speed to subsoil by the compaction was caused directly a poor drainage capacity. However, the properly amended sand soil showed an apparent value of 1,500 Kpa through the subsoil. The water content test showed a similar result that higher rate of 20~30% and ideal rate of 8~12% at poor drainage area and successfully amended area, respectively. However, an imported topsoil media which had higher content of silt and clay from a trans-planted sod had made a heterogeneous soil profile and that caused a poor drain capacity by a low infiltration rate. Those drainage problems triggered to buildup a reduced soil layer by poor soil gas exchange. The soil environment of deoxidation enhanced anaerobic microbial population and induced methane gas build-up to 55 ppm, and that resulted an adverse effect on turf growth by root growth retardation, consequently.