• Journal of the Korea Concrete Institute
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• v.13 no.2
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• pp.107-113
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• 2001

This study was conducted preliminarily to develop the crack source location technique for plain concrete beam using acoustic emission(AE). Before the main experiment, the test of virtual An source location was achieved in plain concrete block. The sensor layout was mutually compared between triangular layout and rectangular layout. As the results of test, AE source location by triangular layout was evaluated more effective than that by rectangular layout. The specimen to apply he source location technique was man in total nine specimens (each three in 40 %, 50%, 60% of W/C ratio) which the experiment variable was the compressive strength level(W/C ratio). The bending loading method is selected by cyclic loadings to evaluate the degree of concrete damage. It is seen that Kaiser effect and Felicity effect exists through analysis of AE parameters in coming failure experiment. As a result of analyzing the felicity ratio(FR) values, it is shown that this values can be used for evaluating the degree of concerto damage. AE activity is started highly at the 70% of failure load without the compressive strength level. Thus considered by a index in constructing the system of the failure warning at application of the field structure. And the results compared the real cracking location with the source location has perceived by AE monitoring before it is appeared the primary crack by visual observation.

• Phonetics and Speech Sciences
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• v.7 no.2
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• pp.47-54
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• 2015

The objectives of this study are to research the frequency of depression symptom in patients with voice disorders and to investigate parameters associated with depression from voice evaluation. A hundred ninety six patients(106 males and 90 females) who had been diagnosed with voice disorders first in their lifetime were selected. All the patients were examined by laryngeal stroboscopy. For depression and voice study, personal interview, acoustic and aerodynamic analysis, voice handicap index(VHI), reflux symptom index(RSI), and beck depression index(BDI) were done respectively. Mild to severe BDI were seen in 26.2%(52 patients) of the whole patients. A BDI mean score of female patients was $8.8{\pm}7.5$ which was higher than that of male patients($5.6{\pm}6.6$), the difference observed being statistically significant(p<0.001). In the acoustic analysis, the score of sent_duration parameter was increasing in the patients with depression, which was significantly higher than the score of the patients without depression(p<0.05). In the addition, the scores of VHI and RSI were higher in the patients with depression(p<0.001). Our findings suggest that the prevalence of depression in patients with voice disorders is related to female, speaking velocity, and self-questionnaire. This result can be used for psychologically based approach to therapy.

• Entomological Research
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• v.48 no.6
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• pp.522-532
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• 2018

As the vector-borne diseases rapidly increased due to climate change, we investigated the incidence of flavivirus occurrence among female mosquito species in urban and rural study sites in Daegu and Gunwi, South Korea using Realtime PCR. We collected more individuals and more species of mosquito in 2016 than in 2015. In 2015, we recorded a total of 22,033 mosquitoes (Trap Index, 224.8) representing 10 species from 5 genera, whereas in 2016, a total of 27,137 mosquitoes (Trap Index, 278.7) representing 13 species from 6 genera were collected. The number of mosquitoes in 2016 was higher in all study sites, except in the migratory bird habitats where the number decreased. Of the 14 species collected over the two years, Aedes vexans nipponii and Anopheles spp. were dominant in the cowsheds in rural farmland; Culex pipiens complex, in urban residential areas; and, Anopheles spp. and Cu. pipiens complex in migratory bird habitats caught in a black light trap. Cu. pipiens complex and Ae. albopictus in urban parks and Ae. albopictus and Armigeres subalbatus in migratory bird habitats were the dominant species caught in BG-sentinel traps. We found that the number of mosquitoes was highest during July-September. We analyzed 1,725 pools to detect flavivirus, where Chaoyang virus was detected among Ae. vexans niponii collected from cowsheds in rural farmland in 2016. The increased number of mosquitoes recorded in 2016 was mainly due to increased temperatures in the study areas, and reflected the change in study sites.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.75-78
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• 2003

This study is to present a method of land cover change detection by the typhoon RUSA (August 1 - September 4, 2002) using Landsat 7 ETM+ images. For the Namdae-cheon watershed in Gangreung, two images of Sept. 29, 2000 and Nov. 22, 2002 were prepared. To identify the damaged areas, firstly, the NDVI (Normalized Difference Vegetation Index) of each image was computed, secondly, the NDVI values were reclassified as two categories that the negative index values including zero are the one and the positive index values are the other, thirdly the reclassified image before typhoon is subtracted from the reclassified image after typhoon to get DNDVI (Differential NDVI). From the DNDVI image, the flooded and damaged areas could be extracted.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.1300-1304
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• 2004

This study is to present a method of flood damaged area detection by the typhoon RUSA (August 31 - September 1, 2002) using Landsat 7 ETM+ and Landsat 5 TM images. Two images of Sept. 29, 2000 and Sept. 11, 2002 (path 115, row 34) were prepared for Gangreung, To identify the damaged areas, firstly, the NDVI (Normalized Difference Vegetation Index) of each image was computed, secondly, the NDVI values were reclassified as two categories that the negative index values including zero are the one and the positive index values are the other, thirdly the reclassified image before typhoon is subtracted from the reclassified image after typhoon to get DNDVI (Differential NDVI). Some part of urban and agricultural were classified into damaged area due to typhoon RUSA in Gangreung, $18.8km^2$ and $17.7km^2$ respectively.

• Journal of the Korean Vacuum Society
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• v.6 no.S1
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• pp.75-79
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• 1997

Optical and mechanical characteristics of $TiO-2, ZrO_2 \;and\; SiO_xN_y$ thin films prepared by ion assisted deposition (IAD) were investigated. IAD films were bombarded by Ar or nitrogen ion beam from a Kaufman ion source while they were grown in as e-beam evaporator. The result shows that the Ae IAD increases the refractive index and packing density of $TiO_2 films close to those of the bulk. For $ZrO_2$ films the Ar IAD increases the average refractive index decreases the negative inhomogeneity of refractive index and reverses to the positive inhomogeneity. The optical properties result from improved packing density and denser outer layer next to air The Ar-ion bombardment also induces the changes in microstructure of $ZrO_2$ films such as the preferred (111) orientation of cubic phase increase in compressive stress and reduction of surface roughness. Inhomogeneous refractive index SiOxNy films were also prepared by nitrogen IAD and variable refractive index of $SiO_xN_y$ film was applied to fabricate a rugate filter.

• Korean Journal of Ecology and Environment
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• v.44 no.2
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• pp.155-171
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• 2011

The research assessed water quality using physico-chemical factors, trophic status index and attached diatom index in 10 reservoirs located in Chungcheongnam-do from October 2007 to June 2008. The physico-chemical water quality assessments revealed that Dangjin-gun (St. 1~5), which displayed a high chemical oxygen demand (V and VI) and chlorophyll-${\alpha}$ (Eutrophic-Hypereutrophic), was more polluted than Yesan and Cheongyang-gun. The sample were also hypereutrophic [trophic status index (TSI) 74.6] and ${\beta}$-mesosaprobic [diatom assemblage index to the organic water pollution (DAIpo) 44.47]. Yesan and Cheongyang-gun. Which were mid-level in their pollution status, were eutrophic (TSI 56.9) and ${\alpha}$-oligosaprobic (DAIpo 60.11). TSI correlated strongly with the attached diatom index (of DAIpo 0.60~0.62, and trophic diatom index of 0.72~0.74). Hence, the attached diatom index can be used with the trophic status assessment of lakes using TSI, and lake trophic status index (LTSI).

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.5
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• pp.899-904
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• 2002

Aloe and propolis are extensively used in folk medicine. Ethanol extracts of Aloe vera (AE), ethanol extract of propolis (PE) and waxfree extract of propolis (PW) were prepared to test antimicrobial activities against five oral microorganisms (Streptococcus mutans, Enterococcus faecalis, Enteococcus hirae, Escherichia coli, Candida albicans). Antimicrobial activities were tested by serial broth dilution method and expressed by minimal inhibitory concentration (MIC). The AE showed relatively weak antimicrobial activities, while both of PE and PW greatly inhibited all microorganisms tested. To investigate the antimicrobial effects of the combined extracts of aloe with propolis, the fractional inhibitory concentration index (FICI) was determined by checkerboard assay for each strain. The combination of AE with PE or PW resulted in Synergistic effect against oral microorganisms tested (FICI=0.375) except Escherichia coli (FICI=1.0 for PE, FICI=0.75 for PW).

• Journal of Korean Biological Nursing Science
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• v.4 no.2
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• pp.5-18
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• 2002

Purpose: Women have been often underdiagnosed and undertreated when they have as high mortality as men of ischemic heart disease, such as angina. One of the reasons of women's under treatment is associated with either vague, non-traditional symptoms or longer delay in seeking professional help when they experience ischemic heart disease. This study was conducted to investigate the characteristics of women's anginal pain induced by the treadmill test and to explore the potential relationship(s) between anginal pain and other psycho-physiologic factors. Methods: Of 22 female patients referred to treadmill test, 7 with positive finding participated in this study. Anginal pain in the past was analyzed by Rose questionnaire, whereas anginal pain induced by the treadmill test was identified by McGill pain scale, visual analogue scale and present pain index. Results: Women expressed more heaviness than sharp pain, and complained splitting more often than subjects in previous study that included both men and women. Pain intensity by VAS $3.64{\pm}3.94$, Pain rating index was $5.14{\pm}7.29$, present pain index was $1.57{\pm}1.81$, duration of pain was $5.14{\pm}4.8$ min. Exercise intensity was $6.0{\pm}4.63$ METs, exercise duration was $364.29{\pm}141.39$ sec, ST change was -2.0mm and rate of perceived exertion was $16.29{\pm}2.06$. The relationships between pain intensity and pain duration, ST segment changes were significant. Correlation among pain measures was significant. Conclusion: Generalization of these pilot findings may be inappropriate, and therefore, further larger study is needed.

• The Journal of Bigdata
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• v.6 no.1
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• pp.23-35
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• 2021

In the era of the 4th industrial revolution, smart factories have received great attention, where production and manufacturing technology and ICT converge. With the development of IoT technology and big data, automation of production systems has become possible. In the advanced manufacturing industry, production systems are subject to unscheduled performance degradation and downtime, and there is a demand to reduce safety risks by detecting and reparing potential errors as soon as possible. This study designs a model based on supervised and unsupervised learning for detecting anomalies. The accuracy of XGBoost, LightGBM, and CNN models was compared as a supervised learning analysis method. Through the evaluation index based on the confusion matrix, it was confirmed that LightGBM is most predictive (97%). In addition, as an unsupervised learning analysis method, MD, AE, and LSTM-AE models were constructed. Comparing three unsupervised learning analysis methods, the LSTM-AE model detected 75% of anomalies and showed the best performance. This study aims to contribute to the advancement of the smart factory by combining supervised and unsupervised learning techniques to accurately diagnose equipment failures and predict when abnormal situations occur, thereby laying the foundation for preemptive responses to abnormal situations. do.