• Allergy, Asthma & Immunology Research
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• v.10 no.6
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• pp.614-627
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• 2018

Purpose: Asthma is a heterogeneous disease that responds to medications to varying degrees. Cluster analyses have identified several phenotypes and variables related to fixed airway obstruction; however, few longitudinal studies of lung function have been performed on adult asthmatics. We investigated clinical, demographic, and inflammatory factors related to persistent airflow limitation based on lung function trajectories over 1 year. Methods: Serial post-bronchodilator forced expiratory volume (FEV) 1% values were obtained from 1,679 asthmatics who were followed up every 3 months for 1 year. First, a hierarchical cluster analysis was performed using Ward's method to generate a dendrogram for the optimum number of clusters using the complete post-FEV1 sets from 448 subjects. Then, a trajectory cluster analysis of serial post-FEV1 sets was performed using the k-means clustering for the longitudinal data trajectory method. Next, trajectory clustering for the serial post-FEV1 sets of a total of 1,679 asthmatics was performed after imputation of missing post-FEV1 values using regression methods. Results: Trajectories 1 and 2 were associated with normal lung function during the study period, and trajectory 3 was associated with a reversal to normal of the moderately decreased baseline FEV1 within 3 months. Trajectories 4 and 5 were associated with severe asthma with a marked reduction in baseline FEV1. However, the FEV1 associated with trajectory 4 was increased at 3 months, whereas the FEV1 associated with trajectory 5 was persistently disturbed over 1 year. Compared with trajectory 4, trajectory 5 was associated with older asthmatics with less atopy, a lower immunoglobulin E (IgE) level, sputum neutrophilia and higher dosages of oral steroids. In contrast, trajectory 4 was associated with higher sputum and blood eosinophil counts and more frequent exacerbations. Conclusions: Trajectory clustering analysis of FEV1 identified 5 distinct types, representing well-preserved to severely decreased FEV1. Persistent airflow obstruction may be related to non-atopy, a low IgE level, and older age accompanied by neutrophilic inflammation and low baseline FEV1 levels.

• Bulletin of the Korean Chemical Society
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• v.16 no.11
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• pp.1067-1074
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• 1995

Reaction of arachno-S2B7H8- with either THF or 1,2-dimethoxyethane upon refluxing condition results in the formation of the previously known compound hypho-S2B7H10-. Protonation of hypho-S2B7H10- with HCl/Et2O generates hypho-2,5-S2B7H11 in good yield. This hypho-S2B7H10- anion has been employed to generate a series of new nido-, arachno-, and hypho-metalladithiaborane clusters. Reaction of the anion with Cp(CO)2FeCl results in direct metal insertion and the formation of a complex containing the general formula (η5-C5H5)FeS2B7H8. Spectroscopic studies of nido-6-CpFe-7,9-S2B7H8 Ⅰ demonstrated that compound Ⅰ was shown to have an nido-type cage geometry derived from an octadecahedron missing one vertex, with the iron atom occupying the three-coordinate 6-position in the cage and the two sulfurs occupying positions on the open face of the cage. Reaction of hypho-S2B7H10- with CoCl2/Li+[C5H5]- gave the previously known complex arachno-7-CpCo-6,8-S2B6H8 Ⅱ. Also, the reaction of the anion with [Cp*RhCl2]2 gave the complex arachno-7-Cp*Rh-6,8-S2B6H8 Ⅲ, the structure of which was shown to be that of complex Ⅱ. The similarity of the NMR spectra of Ⅱ and Ⅲ suggest that Ⅲ adopts cage structure similar to that previously confirmed for Ⅱ. A series of 9-vertex hypho clusters in which the sulfur atoms are bridged by different species isoelectronic with a BH3 unit, such as HMn(CO)4 or SiR2 have been prepared. Compounds Ⅳ,Ⅴ and Ⅵ are each 2n+4 skeletal electron systems and would be expected according to skeletal electron counting theory to adopt hypho-type polyhedral structures derived from an icosahedron missing three vertices. The complex hypho-1-(CO)4Mn-2,5-S2B6H9 Ⅳ was obtained by the reaction of the anion with (CO)5MnBr and has been shown from spectroscopic data to consist of a (CO)4Mn fragment bound to the two sulfur atoms S2 and S5 of hypho-S2B7H10-. Also, similar hypho-type complexes hypho-1-R2Si-2,5-S2B6H8 (R=CH3 Ⅴ, R=C6H5 Ⅵ) have been prepared from the reaction of hypho-S2B7H10- with R2SiHCl.

• Animal Systematics, Evolution and Diversity
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• no.nspc5
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• pp.29-46
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• 2005

As a commemorative joint survey for the 20th anniversary of the Korean Society of Systematic Zoology, molluscan fauna of Jindo Island was investigated from the materials collected from 3 localities of Jindo Island from 29th to 30th of June, 2004. A total of 77 species of 37 families were identified. Among them, 26 species of 18 families are reported for the first time in this area, including Onchidella kurodai (Taki, 1935) that is new to Korean fauna. For O. kurodai, external morphologies were described in detail with illustrations. Combining the present data with those of the previous works revealed that a total of 115 species from 43 families have been recorded in Jindo Island and its adjacent areas thus far. From a biogeographic point of view, some gastropod species (Bittium craticulatum, Mocroschisma dilatatum, Cantharidus japonicus, C. callichroa, Homalopoma sangarense, and Crepidula onyx) encountered from Jindo Island were the species previously recorded in the southern and/or eastern offshores of Korean peninsula, including Jeju Island (Choe, 1992). Along with the fact that Jindo Island contains a large number of molluscan species ranging over the Yellow Sea coast, this finding is another line of evidence supporting the Kim and Kwon (1983)'s idea that this area is an overtopping zone of marine organisms which dwell in both the Yellow sea and southern part of Korean sea waters. No comprehensive faunistic survey was not made in the present study. We expect that further supplementary study would generate more biogeographic and faunistic knowledges than what we understand through the present study.

• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.6
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• pp.513-524
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• 2022

Recently, detecting damages of civil infrastructures from digital images using deep learning technology became a very popular research topic. In order to adapt those methodologies to the field, it is essential to explain robustness of deep learning models. Our research points out that the existing pixel-based deep learning model evaluation metrics are not sufficient for detecting cracks since cracks have linear appearance, and proposes a new evaluation methodology to explain crack segmentation deep learning model more rationally. Specifically, we design, implement and validate a methodology to generate tolerance buffer alongside skeletonized ground truth data and prediction results to consider overall similarity of topology of the ground truth and the prediction rather than pixel-wise accuracy. We could overcome over-estimation or under-estimation problem of crack segmentation model evaluation through using our methodology, and we expect that our methodology can explain crack segmentation deep learning models better.

• The Journal of the Korea Contents Association
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• v.19 no.8
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• pp.500-512
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• 2019

Recently, almost all industries are focusing on improving the competency of related industry workers, and it is necessary to design a systematic educational activity plan that constructs, operates and evaluates learning experiences for knowledge, technology and literacy development required in the industrial field. This study performed a questionnaire survey on students' satisfaction with 2015 and 2014 curriculum and national competency standards (NCS)-based one which has been applied since March 2016 against those from Department of Beauty & Cosmetology, 'C' University. For data analysis, frequency analysis, qualitative analysis and SWOT analysis were conducted, and the results found the followings: The NCS-based curriculum which has been applied since 2016 is more advanced than 2015 and 2014 curriculum in terms of strength, weakness, risk and opportunity. In addition, their satisfaction with curriculum was more than average with 47.9-57.2%. Meanwhile, when asked their favorite time to decide their academic major, 79.5% answered, '2nd semester of the 1st year'. They were very dissatisfied with the fact that their academic major is decided in the second year. It is anticipated that the NCS-based 2-year curriculum for Dept. of Beauty & Cosmetology is redesigned through analysis of students' satisfaction and by reflecting their opinions. It is also expected that the reorganization of the curriculum in a more practical and systematic manner would increase students' satisfaction and generate workforce for cosmetology industry.

• Environmental and Resource Economics Review
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• v.28 no.2
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• pp.307-326
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• 2019

The electric vehicle is a representative measure to reduce greenhouse gas and local air pollutants in the transportation sector. Most countries provide purchase subsidies and tax reductions to promote electric vehicle sales. The electric vehicles have been considered as zero-emission vehicles(ZEV) in light of the fact that there has been no pollutant emission during driving. However, recent studies have pointed out that the pollutant emitted from the process of generating electricity used for charging the electric vehicles need to be treated as emissions of the electric vehicles. Furthermore, the environmental benefits of electric vehicle replacing the internal combustion vehicle vary with the power mix. In line with the recent studies, this study analyzes the impact of electric vehicles based on the current power mix and future energy transition scenarios in Korea. To estimate the precise air pollutants emission profile, this study uses hourly electricity generation and TMS emission data for each power plant from 2015 to 2016. The estimation results show that the electric vehicles under the current power mix generate the environmental benefits of only -0.41~10.83 won/km. Also, we find that the environmental benefit of electric vehicle will significantly increase only when the ratio of the coal-fired power plant is reduced to a considerable extent.

• Journal of Climate Change Research
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• v.3 no.1
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• pp.13-24
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• 2012

CCGIS (Climate Change Adaptation Toolkit based on GIS) was developed to use as a tool for the climate change assessment and any relevant tasks involving climate change adaptation policy over Korean peninsula. The main objective of CCGIS is to facilitate an efficient and relevant information for the estimation of climate change vulnerability index by providing key information in the climate change adaptation process. In particular, the atmospheric modeling system implemented in CCGIS, which is composed of climate and meteorological numerical model and the atmospheric environmental models, were used as a tool to generate the climate and environmental IPCC SRES (A2, B1, A1B, A1T, A1FI, and A1 scenarios) climate data for the year of 2000, 2020, 2050, and 2100. This article introduces the components of CCGIS and describes its application to the Korean peninsula. Some examples of the CCGIS and its use for both climate change adaptation and estimation of vulnerability index applied to Korean provinces are presented and discussed here.

• Korean Journal of Heritage: History & Science
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• v.42 no.4
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• pp.4-19
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• 2009

Though admitting that, in light of the recent archaeological trend, the excavation on relics of Sam-gama (a sort of kiln steaming the hemp) is increasingly reported, little efforts by far have been made not only to restore its traditional structure design but also to research hardly the change of hemp-steaming technologies in ages. In this regard, this paper shows the exploration of structural method and design as well as operability with regard to Sam-gut, traditional hemp-processing equipment that was recently reconstructed in Jungsun, Kangwon Province. Samgut, generally positioned at the waterside area, is an traditional device for steaming hemp to get bast fibers from the raw material of hemp, principally consisting of HWA-JIP(fire-place) to obtain steams by feeding fire ad Mong-got(boiling chamber) to make the hemp steamed after stacking. More specifically, thick round-logs were piled at the bottom of Hwajip prior to stacking stones around its circumferential area. When the timber positioned below gets burned with high temperature to heat stones existing in the upper side, waters then poured onto it after laying a bundle of grass and soil up to the boiled stones. If so, there generates hot vapor, which is conveyed to Monggot to steam the hemp. Functionally, it is of outstanding importance that Samgut is capable of producing high-temperature water vapors instantaneously under the intensive manpower, thus being constructed achievable for those purposes. The Samgut made by digging the ground is an instant facility that is closed after use. The remains, which were used to generate higher thermal power for steaming hemp, make it hard to excavate the historic traits because there left little vestiges in the soil, which means keen attention must be paid to find out the trace of Smgama relics. Future research stall be focused on collection of broader data regarding Samgut including technological review in extracting bas fibers from the hemp.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.7
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• pp.820-828
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• 2017

Tools and equipment that can provide buoyancy for a drowning person are important for saving lives. The purpose of this study was to estimate the minimum amount of gas needed and the buoyancy value in newton units required to generate the minimum buoyancy determined to be sufficient for keeping the head of a drowning person above the water's surface to allow for respiration for at least 1 minute. A buoyancy experiment was carried out with a long rubber balloon injected with carbon dioxide gas, and a buoyancy measurement experiment was performed on six college students. The degree of buoyancy was measured using a 5-point scale, and the statistical value of the measured data was analyzed to estimate minimum buoyancy. As a result, 8 grams of carbon dioxide were determined to satisfy minimum buoyancy conditions with a confidence level of 72%, and buoyancy was calculated to be 44.66 newtons. 12 grams of carbon dioxide met the minimum buoyancy conditions with a confidence level of 100%, and buoyancy was calculated to be 66.99 newtons. This study is expected to contribute to the development of low cost, easy-to-carry minimum buoyancy aids.

• Journal of Broadcast Engineering
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• v.24 no.3
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• pp.495-505
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• 2019

Typical algorithms of deep learning include CNN(Convolutional Neural Networks), which are mainly used for image recognition, and RNN(Recurrent Neural Networks), which are used mainly for speech recognition and natural language processing. Among them, CNN is able to learn from filters that generate feature maps with algorithms that automatically learn features from data, making it mainstream with excellent performance in image recognition. Since then, various algorithms such as R-CNN and others have appeared in object detection to improve performance of CNN, and algorithms such as YOLO(You Only Look Once) and SSD(Single Shot Multi-box Detector) have been proposed recently. However, since these deep learning-based detection algorithms determine the success of the detection in the still images, stable object tracking and detection in the video requires separate tracking capabilities. Therefore, this paper proposes a method of combining Kalman filters into deep learning-based detection networks for improved object tracking and detection performance in the video. The detection network used YOLO v2, which is capable of real-time processing, and the proposed method resulted in 7.7% IoU performance improvement over the existing YOLO v2 network and 20 fps processing speed in FHD images.