• Journal of the Institute of Electronics Engineers of Korea SC
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• v.46 no.4
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• pp.28-38
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• 2009

In this study, a remote air quality monitoring system for underground spaces was developed by using NDIR-based CO$_2$ sensor. And the remote monitoring system based on wireless sensor networks was installed practically on the subway station platform. More than 6.5 million citizens commutate everyday by the Seoul subway transportation that is the most typical public transportation. They concern about air quality with increasing interest on public health or many workers in subway stations or underground shopping centers. Recently, the Korean Ministry of Environment has operated the air quality monitoring system in some subway stations for testing phase. However, it showed many defects which are large-scale, high-cost and maintenance of precision sensors imported from abroad. Therefore this research includes the reliability test and a theoretical study about the inexpensive commercialized CO$_2$ sensor for reliable measurement of air quality which changes rapidly by the surrounding environments. And then we develop the wireless sensor nodes and the gateway applied for remote air quality monitoring. In addition, web server program was realized to manage air quality in the subway platform. This result will be valuable for a basic research for air quality management in underground spaces for future study.

• Journal of Digital Convergence
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• v.12 no.2
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• pp.315-320
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• 2014

Recently, although the requirement of quality of VOD content has been transferred upto the class of HD, conventional management systems characterized by OS dependency are truly limited in quality of video image, stability, and compatibility of network environments. In addition most of the content management systems realize very limited capabilities for the real affairs of content management and distribution services in such an OS dependent environment. In this paper, we propose a new scheme of HD-Class VOD Content Management System to solve these problems. We design and implement the proposed system based on open sources by using H.264 video compression method. The proposed system offers high quality content management method based on opened systems and independent on-line distribution method so that it can be realized as an integrated management scheme for VOD contents. Moreover, our system solves the problems of occasional cutting-down video, small screen, and poor image quality that exist in the conventional wmv-type CMS. According to the result of performance evaluation, our system maintains sufficient performance and tolerence for the case of large scale HD content operations or fabrications. We expect that the proposed integrated DB scheme will especially be effective when the content management applications are changed from Internet Web environments to mobile terminal environments.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.315-315
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• 2017

In Japan, more than 80 % of soybean growing area is converted fields and excess water is one of the major problems in soybean production. For example, recent study (Yoshifuji et al., 2016) suggested that in the fields of shallow groundwater level (GWL) (< 1m depth), rising GWL even in a short period (e.g. 1 day) causes inhibition of soybean growth. Thus it becomes more and more important to predict GWL and soil moisture in detail. In addition to conventional surface drainage and underdrain, FOEAS (Farm Oriented Enhancing Aquatic System), which is expected to control GWL in fields adequately, has been developed recently. In this study we attempted to predict GWL and soil moisture condition at the converted field with FOEAS in Biwa lake reclamation area, Shiga prefecture, near the center of the main island of Japan. Two dimensional HYDRUS model (Simuinek et al., 1999) based on common Richards' equation, was used for the calculation of soil water movement. The calculation domain was considered to be 10 and 5 meter in horizontal and vertical direction, respectively, with two layers, i.e. 20cm-thick of plowed layer and underlying subsoil layer. The center of main underdrain (10 cm in diameter) was assumed to be 5 meter from the both ends of the domain and 10-60cm depth from the surface in accordance with the field experiment. The hydraulic parameters of the soil was estimated with the digital soil map in "Soil information web viewer" and Agricultural soil-profile physical properties database, Japan (SolphyJ) (Kato and Nishimura, 2016). Hourly rainfall depth and daily potential evapo-transpiration rate data were given as the upper boundary condition (B.C.). For the bottom B.C., constant upward flux, which meant the inflow flux to the field from outside, was given. Seepage face condition was employed for the surrounding of the underdrain. Initial condition was employed as GWL=60cm. Then we compared the simulated and observed results of volumetric water content at depth of 15cm and GWL. While the model described the variation of GWL well, it tended to overestimate the soil moisture through the growing period. Judging from the field condition, and observed data of soil moisture and GWL, consideration of soil structure (e.g. cracks and clods) in determination of soil hydraulic parameters at the plowed layer may improve the simulation results of soil moisture.

• Journal of Science Education
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• v.32 no.2
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• pp.121-145
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• 2008

The purposes of this study were to identify the misconceptions that students have on the magma and plate tectonics and to present the implications in developing textbooks as well as related curriculum of high school textbooks. Data were collected through questionnaire, consisting of some questions, short essays, and descriptive drawings, developed by the research team. A total of 140 high school students(9th graders) responded to those questionnaires and were interviewed for further information. It was reported that participants displayed various misconceptions related to magma and plate tectonics. The identified misconceptions are as follows: For the definition of magma, the 31% of participants misunderstood magma as lava. In respect to the generative mechanism of magma at subduction zone, over 90% of students responded that it is generated by frictional heat. The source of misconceptions were identified as a result from textbooks and related reference-books. For the concept of plates, 87% of students conceived 'crust or a lower part of the plates' as 'plates'. Most participants hold the right concept of oceanic ridge, whereas, 66% of them considered 'rift valley' as either 'divergence of continental plates' or 'converging boundary'. 63% of them defined 'collision boundary of continental plate' as either 'subduction zone' or 'diverging boundary'. For the definitions of the trench and Benioff zone, 86% of students responded them as the place of subduction or differing density between two converging plates. The students' misconceptions were resulted from the errors and insufficient explanation, inappropriate figures, and data presented in textbooks, reference-books, lecture, and web sites. The results of this study are implied to contribute the improvement of students' misconceptions.

• Science of Emotion and Sensibility
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• v.13 no.1
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• pp.207-214
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• 2010

The aim of this study was to investigate upper and lower limb muscle activity using EMG(electromyogram) sensors while walking and identify normal gait pattern using FSR(force sensing resistor) sensor. Fifteen college students participated in this study and their EMG and FSR signal were measured during stopping and walking trials. EMG signals from upper(pectoralis major and trapezius) and lower limbs(rectus femoris, biceps femoris, vastus medialis, vastus lateralis, semimembranosus, semitendinosus, soleus, peroneus longus, gastrocnemius medialis, and gastrocnemius lateralis) were obtained using the surface electrodes. FSR measured pressures on 8 areas of the sole of the foot during walking. EMG results showed that all muscle activities except for vastus lateralis and semimembranosus during walking had higher amplitudes than stopping. Additionally, muscle activities associated with stance and swing phase during walking were identified. Results on FSR showed that stance and swing phases were detected by FSR signals during a gait cycle. Eight gait phases－initial contact, loading response, mid stance, terminal stance, pre swing, initial swing, mid swing, and terminal swing- were classified.

• The Journal of Korean Society for School & Community Health Education
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• v.17 no.3
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• pp.11-25
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• 2016

Background & Objectives: There were increasing evidence about the relationship between allergy related disease such as asthma, atopic dermatitis and allergic rhinitis and suicide ideation. However little was known about the concrete relatedness between severity and comorbidity of allergy related disease with suicide ideation. The objective of this study was to investigate the cases of the prevalence of suicide ideation among adolescents with allergy related disease such as asthma, atopic dermatitis and allergic rhinitis, and examine the association between allergy related disease and suicidal ideation among adolescents in South Korea. Methods: Data was based on Korean Youth Risk Behavior Web-based Survey(2014) which was a cross-sectional study containing 34,874 Korean middle and high school students who diagnosed with allergy related disease. We used the weights, strata and primary sampling unit information provided by the public use dataset to compute descriptive statistics and logistic regressions. Computations were done with SPSS version 20.0. Results: 19.9%, 15.6%, 13.8% of adolescents who suffered from one, two and three of allergy related diseases respectively reported having been thought of suicide ideation. Socio-demographic factors were adjusted as control variables. Students with greater severity of disease were more likely to have suicide ideation. Odds ratio for students who were absent one to three days from school because of allergies was 1.96(95% CI 1.51-2.46), and odds ratio for those who were absent more than four days from school was 3.60(95% CI 2.46-5.28). Conclusions: Given that adolescents' severity and comorbidity of allergy related disease were clearly associated with suicide ideation, suicide prevention programs for adolescents with allergy related disease should be improved by strategic approaches towards the severity and comorbidity of disease.

• Tuberculosis and Respiratory Diseases
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• v.66 no.2
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• pp.141-151
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• 2009

Background: There is limited data on the epidemiology and relative frequency of idiopathic interstitial pneumonia (IIP) worldwide. This survey was performed to assess the epidemiology and relative frequency of IIP in Korea. Methods: The patients with IIP and who were confirmed by lung biopsy, except those patients with idiopathic pulmonary fibrosis, (IPF) over a 5 year period (from Jan. $1^{st}$, 2003 to Dec. $31^{st}$, 2007) were registered by a web-base questionnaire. Results: A total of 3,156 cases were registered, but 970 cases were excluded due to duplicative registration, inadequate data and the unmet ATS/ERS diagnostic criteria. A total of 2,186 cases were analyzed. The male to female ratio was about 2 : 1 and their mean age was 65 (range: 11-94). The most frequent disease was IPF (77.1%), followed in decreasing order by nonspecific interstitial pneumonia (NSIP) (11.9%), cryptogenic organizing pneumonia (COP) (8.5%), acute interstitial pneumonia (AIP) (1.1%), desquamative interstitial pneumonia (DIP) (0.9%), respiratory bronchiolitis-interstitial lung disease (RB-ILD) (0.4%) and lymphocytic interstitial pneumonia (LIP) (0.1%). The mean age of the patients with IPF, NSIP and COP was 67.8, 57.1 and 57.7 years old, respectively. The most frequent symptom was dyspnea on exertion (69%) followed by coughing (61%) and sputum (33%) for the whole population. The three year survival rate was 62% for the patients with IPF and the five year survival rate was 85% in both the NSIP and COP patients. Conclusion: This survey provides helpful information for the management of IIP and to produce management guidelines for this illness in Korea.

• Journal of Korea Game Society
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• v.12 no.2
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• pp.75-89
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• 2012

In this paper, the correlation which is at work between affecting factors and interpersonal relationships' dimension depend on developmental level has been studied to search for clues about how to develop the online based interpersonal relationships -the fundamental aims of SNS related services- efficiently. People who'd ever entered into a relation through the 'online-based generated relationship' by SNS were divided into two groups on the development level. They were conducted a survey, and the results were derived using PLS statistics. As the result, 7 kinds of factors as social attraction, physical attraction, reciprocity, content quality, coexistence perception, information provision and similarity had an impact on the initial level of relationships, and 6 kinds of factors as social attraction, physical attraction, reciprocity, content quality, web appearance and coexistence perception had an impact on the developed level of relationships. This study could be utilized for the service design for facilitating interpersonal relationships efficiently by their level of development.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.8
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• pp.3403-3410
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• 2014

Context: Interest exits in whether TNF-alpha antagonists increase the risk of breast cancer and total malignancies in patients with rheumatoid arthritis (RA). Objectives: To analyze the risk of malignancies, especially breast cancer, in patients with RA enrolled in randomized control trials (RCTs). Methods: A systematic literature search for RCTs from 1 January 1998 to 1 July 2013 from online databases, such as PubMed, WILEY, EMBASE, ISI web of knowledge and Cochrane Library was conducted. Studies included RCTs that compared the safety of at least one dose of the five TNF-${\alpha}$ antagonists with placebo or methotrexate (MTX) (or TNF-${\alpha}$ antagonists plus MTX vs placebo plus MTX) in RA patients for more than 24 weeks and imported all the references into document management software EndNote${\times}6$. Two independent reviewers selected studies and extracted the data about study design, patients' characteristics and the type, number of all malignancies. Results: 28 RCTs from 34 records with 11,741 patients were analyzed. Of the total, 97 developed at least one malignancy during the double-blind trials, and breast cancer was observed in 17 patients (17.5% of total malignancies). However, there was no statistically significant increased risk observed in either the per protocol (PP) model (OR 0.65, 95%CI [0.22, 1.93]) or the modified intention to treat (mITT) model (OR 0.75, 95%CI [0.25, 2.21]). There were also no significant trend for increased risk of total malignancies on anti-TNF-${\alpha}$ therapy administered at approved doses in either model (OR, 1.06, 95%CI [0.64, 1.75], and OR, 1.30, 95%CI [0.80, 2.14], respectively). As to the two models, modified intention to treat model analysis led to higher estimation than per protocol model analysis. Conclusions: This study did not find a significantly increased risk of breast cancer and total malignancies in adults RA patients treated with TNF-${\alpha}$ antagonists at approved doses. However, it cannot be ignored that more patients developed malignancies with TNF-${\alpha}$ antagonists therapy compared with patients with placebo or MTX, in spite of the lack of statistical significance, so that more strict clinical trials and long-term follow-up are needed, and both mITT and PP analyses should be used in such safety analyses.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.sup3
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• pp.323-335
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• 2016

Breast cancer risk assessment has developed during years and evaluation of genetic factor affecting risk of breast cancer is an important component of this risk assessment. The aim of this meta-analysis was to investigate the role of XRCC1 polymorphisms (Arg194Trp, Arg280His and Arg399Gln) in risk of breast cancer among different population and categories of menopausal status.PubMed, Medline, Web of Science, and PubMed Central were systematically searched to identify studies evaluating association between breast cancer and XRCC1 gene polymorphisms (Arg194Trp, Arg280His and Arg399Gln). Two authors independently extracted required information. Odds Ratios were pooled for four genetic inheritance models using both fixed and the DerSimonian and Laird random-effect models. Egger's test and contour-enhanced funnel plot was used to evaluate publication bias and small study effect. Additional subgroup analysis was performed for menopausal status, ethnicity, and source of controls. After evaluation and applying inclusion criteria on extracted studies, fifty three studies were included in this meta-analysis. For polymorphisms of Arg194Trp and Arg280His, no significant association was observed in all genetic models. Arg194Trp had a protective effect in post-menopausal status only in homozygote model (OR=0.57 [0.37-0.88]). Arg399Gln showed significant association with breast cancer in homozygote (OR=1.21 [1.10-1.34]), dominant (OR=1.09 [1.03-1.15]) and recessive (OR=1.21 [1.09- 1.35]) genetic models. Arg399Gln was associated with higher risk in post-menopausal status for homozygote and heterozygote models. Our findings suggest that XRCC1 gene polymorphisms modify breast cancer risk in different populations and different categories of menopausal status.