• Korean Journal of Soil Science and Fertilizer
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• v.6 no.4
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• pp.221-226
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• 1973

In order to investigate the silica effect of insufficient wollastonite to the official standard (above than 15% of suluble silica (N/2 HCl) on rice plant as silica fertilizer, 9 kinds of wollastonites and slag were adopted to examine the amount of silica absorbed by rice straw during growing period, and soluble silica of wollastonites extracted by 7 buffer solutions were compared with silica content in rice straw. Crystalls of ingredient in wollastonite ores were identified by X-ray diffractometer. The results were that silica content of rice plant at growing stages were increased as same ratio of soluble silica. content in wollastonite. Wollastonite containing more than 10% of souble silica (N/2 HCl) could be applied as fertilizer because absorbed amount of silica by rice plant from them are higher than from slag which contained 30% of soluble silica. Wollastonite powder mixed with impure ores in which soluble silica could not be extracted had the same effect on silica absorption of straw as wollastonite powder which contained conformable amount of soluble silica. The soluble silica of wollastonite extracted by buffer solutions (2% citric acid, N. NaOAc, N. $NH_4OAc$, Petermann solution, 0.1M. EDTA, and Hot water) had high significant relation to silica content in rice straw, but soluble silica extracted N/2 hydrochloric acid solutilon, also, had deep relation to them in rice straw. The adequate solution to extract silica from wollastonites is N/2 hydrochloric acid solution because its extracted silia amount is much higher than other solution (about one hundred times) and can be determined by gravimetric analysis. X-ray diffraction pattern would identify qualitatively purity of wollastonite, and large amount of soluble silica was extracted from wollastonite which was appeared to be weathered.

• Korean Journal of Remote Sensing
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• v.34 no.2_1
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• pp.267-282
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• 2018

Despite the continuous development of phenology detection studies using satellite imagery, verification through comparison with the field observed data is insufficient. Especially, in the case of Korean forests patching in various forms, it is difficult to estimate the start of season (SOS) by using only satellite images due to resolution difference. To improve the accuracy of vegetation phenology estimation, this study reconstructed the large scaled forest type map (1:5,000) with MODIS pixel resolution and produced time series vegetation phenology curves from Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) derived from MODIS images. Based on the field observed data, extraction methods for the vegetation indices and SOS for Korean forests were compared and evaluated. We also analyzed the correlation between the composition ratio of forest types in each pixel and phenology extraction from the vegetation indices. When we compared NDVI and EVI with the field observed SOS data from the Korea National Arboretum, EVI was more accurate for Korean forests, and the first derivative was most suitable for extracting SOS in the phenology curve from the vegetation index. When the eight pixels neighboring the pixels of 7 broadleaved trees with field SOS data (center pixel) were compared to field SOS, the forest types of the best pixels with the highest correlation with the field data were deciduous forest by 67.9%, coniferous forest by 14.3%, and mixed forest by 7.7%, and the mean coefficient of determination ($R^2$) was 0.64. The average national SOS extracted from MODIS EVI were DOY 112.9 in 2014 at the earliest and DOY 129.1 in 2010 at the latest, which is about 0.16 days faster since 2003. In future research, it is necessary to expand the analysis of deciduous and mixed forests' SOS into the extraction of coniferous forest's SOS in order to understand the various climate and geomorphic factors. As such, comprehensive study should be carried out considering the diversity of forest ecosystems in Korea.

• Journal of Intelligence and Information Systems
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• v.17 no.2
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• pp.61-75
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• 2011

A Geographic Information System(GIS) is a system that captures, stores, analyzes, manages and presents data with reference to geographic location data. In the later 1990s and earlier 2000s it was limitedly used in government sectors such as public utility management, urban planning, landscape architecture, and environmental contamination control. However, a growing number of open-source packages running on a range of operating systems enabled many private enterprises to explore the concept of viewing GIS-based sales and customer data over their own computer monitors. K telecommunication company has dominated the Korean telecommunication market by providing diverse services, such as high-speed internet, PSTN(Public Switched Telephone Network), VOLP (Voice Over Internet Protocol), and IPTV(Internet Protocol Television). Even though the telecommunication market in Korea is huge, the competition between major services providers is growing more fierce than ever before. Service providers struggled to acquire as many new customers as possible, attempted to cross sell more products to their regular customers, and made more efforts on retaining the best customers by offering unprecedented benefits. Most service providers including K telecommunication company tried to adopt the concept of customer relationship management(CRM), and analyze customer's demographic and transactional data statistically in order to understand their customer's behavior. However, managing customer information has still remained at the basic level, and the quality and the quantity of customer data were not enough not only to understand the customers but also to design a strategy for marketing and sales. For example, the currently used 3,074 legal regional divisions, which are originally defined by the government, were too broad to calculate sub-regional customer's service subscription and cancellation ratio. Additional external data such as house size, house price, and household demographics are also needed to measure sales potential. Furthermore, making tables and reports were time consuming and they were insufficient to make a clear judgment about the market situation. In 2009, this company needed a dramatic shift in the way marketing and sales activities, and finally developed a dedicated GIS_based market analysis and sales management system. This system made huge improvement in the efficiency with which the company was able to manage and organize all customer and sales related information, and access to those information easily and visually. After the GIS information system was developed, and applied to marketing and sales activities at the corporate level, the company was reported to increase sales and market share substantially. This was due to the fact that by analyzing past market and sales initiatives, creating sales potential, and targeting key markets, the system could make suggestions and enable the company to focus its resources on the demographics most likely to respond to the promotion. This paper reviews subjective and unclear marketing and sales activities that K telecommunication company operated, and introduces the whole process of developing the GIS information system. The process consists of the following 5 modules : (1) Customer profile cleansing and standardization, (2) Internal/External DB enrichment, (3) Segmentation of 3,074 legal regions into 46,590 sub_regions called blocks, (4) GIS data mart design, and (5) GIS system construction. The objective of this case study is to emphasize the need of GIS system and how it works in the private enterprises by reviewing the development process of the K company's market analysis and sales management system. We hope that this paper suggest valuable guideline to companies that consider introducing or constructing a GIS information system.

• Clinical and Experimental Pediatrics
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• v.52 no.3
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• pp.330-338
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• 2009

Purpose : The causes of acute lower respiratory tract infection (ALRTI) are mostly attributable to viral infection, including respiratory syncytial virus (RSV), parainfluenza virus (PIV), influenza virus A/B (IFV A/B), or adenovirus (ADV). Several Korean studies reported human metapneumovirus (hMPV) as a common pathogen of ALRTI. However, studies on seasonal distribution and clinical differences relative to other viruses are insufficient, prompting us to perform this study. Methods : From November 2006 to October 2007, we tested nasopharyngeal aspiration specimens in children hospitalized with ALRTI with the multiplex reverse transcriptase-polymerase chain reaction to identify 6 kinds of common pathogen (hMPV, RSV, PIV, IFV A/B, and ADV). We analyzed positive rates and clinical features by respiratory chart review. Results : We detected 38 (8.4%) hMPV-positive cases out of 193 (41.8%) virus-positive specimens among 462 patients. HMPV infection prevailed from March to June with incidence peaking in April. HMPV-positive patients were aged 15 years (76.3%), and the ratio of boys to girls was 1.2:1. The median age was 27 months. HMPV primarily caused pneumonia (76.3 %) (P=0.018). Average hospitalization of HMPV-associated ALRTI patients was 5.8 days. In addition, they showed parahilar peribronchial infiltration (100%) on chest X-ray, normal white blood cell count (73.7%), and negative C-reactive protein (86.8 %) (P>0.05). All hMPV-positive patients recovered without complication. Conclusion : HMPV is a common pathogen of ALRTI in Korean children, especially in 1-5 year olds, from March to May. Immunocompetent children diagnosed with hMPV-associated ALRTI may have a good prognosis.

• Journal of Fashion Business
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• v.6 no.2
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• pp.1-16
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• 2002

The need for ready-to-wear clothing increases as the problem comes to arise from the fit of custommade clothing due to the characteristics of middle-aged women's somatotype. At this point of time, a study on the realities of production of custom-made clothing in middle-aged women's clothing business firms is of very greatly significance. Therefore, this study was intended to identify the problem and improvements through the survey research of production of custom-made clothing in middle-aged women's clothing business firms and further present the plan for development of custom-made clothing business. The questionnaire was framed based on the contents extracted from the preliminary questionnaire research for the pattern section chief of each business firm. Collected data were statistically processed using the SPSS 10.0 Windows program. As a result, the following findings were obtained: 1. The target age of the middle-aged women's clothing business firms ranged from more than 45 years to less than 50 years of age. Clothing business firms much made inroads into the ready-to-wear clothing market largely in the 1980s and the 1990s. Their active entry into the custom-made clothing market occurred in the 1970s and the 1980s. 2. In terms of the clothing production method of middle-aged women's clothing firms, some private boutique and designer brand clothing firms entered the clothing market with a focus on custom-made clothing in the beginning of its organization and introduced the production method of ready-to-wear clothing in accordance with changes in production methods and consumers' needs and wants. National brand clothing firms manufactured clothing with a focus on ready-to-wear clothing from the beginning of its organization, but at last they manufactured both partial custom-made and whole custom-made as the problem arose from ready-to-wear clothing. Seeing that their clothing production showed the ratio readyto-wear to custom-made clothing of 2.58:1. And it was found that the manufacture of ready-to-wear and custom-made clothing took into consideration the great difference in the pattern, size and design plan. The research of the clothing production process showed that whole custom-made and partial custommade were distinguished according to whether or not the sample was presented. 3. The ready-to-wear pattern of middle-aged women's clothing firms were used with a focus on the 'patternmaker-developed pattern' and company-developed pattern'. Most clothing businesses produced clothing in 4 to 5 basic sizes, which is found to be insufficient to complement the physical characteristics of middle-aged women with many specific somatotypes. In the pattern of custom-made clothing, the 'pattern of ready-to-wear were applied' or the 'customized pattern was developed'. Actual measurements were most used as the size of custom-made, and accordingly it is predicted that the level of satisfaction is higher with the fit of custom-made clothing than that of ready-to-wear. The selling place and the head office showed the similar percent as the place for measuring the size of custom-made clothing. Size measurers were mostly the shop master. And it was found that most clothing business firms had a problem when the measured size was applied to the pattern. Accordingly, it is necessary to provide education on size measurement for shop masters. 4. It was found that in the middle-aged women's clothing firms, the pattern correction of the length of sleeve, jacket and slacks occupied the highest percent. Accordingly, it is necessary to provide for the size system to complement the accurate somatotype characteristics of middle-aged women. 5. In custom-made clothing customer management, most firms engaged in customer somatotype management through size management. They provided customers with commodity information by informing them of the sales and event period and practiced human management for customers by maintaining the get-together and friendly relationship. 6. Middle-aged women's clothing businesses responded that it would be necessary to improve the fit of custom-made clothing and complement their pursuit for individuality as the plan to improve its quality. In consequence, it suggests that middle-aged women's clothing businesses should provide middle-aged women with the clothing of better-suited size and refined design. Middle-aged women's clothing businesses responded that it was the most urgent task to form the custom-made clothing manufacturing team as the plan to expand the custom-made clothing market, which is identified as their emphasis on the systematized production of custom-made clothing.

• Journal of Korean Society of Transportation
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• v.36 no.2
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• pp.155-168
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• 2018

In this study, we studied the directional pattern of entering the intersection from the intersection upstream link prior to predicting short future (such as 5 or 10 minutes) intersection direction traffic volume on the interrupted flow, and examined the possibility of traffic volume prediction using traffic assignment model. The analysis method of this study is to investigate the similarity of patterns by performing cluster analysis with the ratio of traffic volume by intersection direction divided by 2 hours using taxi DTG (Digital Tachograph) data (1 week). Also, for linking with the result of the traffic assignment model, this study compares the impact area of 5 minutes or 10 minutes from the center of the intersection with the analysis result of taxi DTG data. To do this, we have developed an algorithm to set the impact area of intersection, using the taxi DTG data and traffic assignment model. As a result of the analysis, the intersection entry pattern of the taxi is grouped into 12, and the Cubic Clustering Criterion indicating the confidence level of clustering is 6.92. As a result of correlation analysis with the impact area of the traffic assignment model, the correlation coefficient for the impact area of 5 minutes was analyzed as 0.86, and significant results were obtained. However, it was analyzed that the correlation coefficient is slightly lowered to 0.69 in the impact area of 10 minutes from the center of the intersection, but this was due to insufficient accuracy of O/D (Origin/Destination) travel and network data. In future, if accuracy of traffic network and accuracy of O/D traffic by time are improved, it is expected that it will be able to utilize traffic volume data calculated from traffic assignment model when controlling traffic signals at intersections.

• Tuberculosis and Respiratory Diseases
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• v.62 no.1
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• pp.5-10
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• 2007

Background: Korean national guidelines for examining contacts with active pulmonary tuberculosis (TB) are a tuberculin skin test (TST) and chest radiographs. The treatment of a latent TB infection as performed only in those younger than six years of age who test positive for TST. Although there is a high incidence of active TB in young Korean soldiers, the current national guidelines for controlling contacts with active TB in soldiers are insufficient. This study highlights the problems with the Korean guidelines for controlling a TB outbreak in a small military unit. Material and Methods: In December of 2005, there was a tuberculosis outbreak in a military unit with a total of 464 soldiers in Kyung Gi province. The chest radiographs were taken of all the soldiers, and TST were carried out on 408 candidates. Results: In the first screening of the chest radiographs, two active TB patients were detected. By August of 2006, four additional cases were detected, making a total of six cases after the outbreak. All the patients showed active pulmonary TB or TB pleuritis. When the results of TST in the close contacts and non-close contacts were compared, there was a significant difference in the absolute size of the induration($9.70{\pm}7.50mm$ vs. $6.26{\pm}7.02mm$, p<0.001) as well as the ratio of patients showing an induration > 10mm (50.0% vs. 32.0%, p<0.001) and 15mm (33.2% vs. 20.9%, p= 0.005). Conclusion: Although the national guidelines for managing a TB outbreak in a military unit were followed, there were continuous instances of new active TB cases. This highlights the need for new guidelines to prevent the spread of TB.

• Korean Journal of Environment and Ecology
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• v.25 no.3
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• pp.358-364
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• 2011

To examine the possibility of natural regeneration of six Acer species in broadleaved mixed forest in Korean peninsula, samples of six Acer species' samaras were collected at several seed sources from September to October 2009 and 2010, and seed morphological characteristics and viability were studied using cutting method. Inflorescense type of Acer mandshuricum(AM), A. pseudosieboldianum(APS) and A. palmatum(AP) is corymb, that of A. pictum subsp. mono(APSM) and A. okamotoanum(AO) is flat-topped panicle, and that of A. ukurunduense(AU) is raceme. Number of seed-set per inflorescense proves the highest value 38.5 sets in AU and the lowest value 2.4 sets in APS. Diameter of the seeds proves highest value 13.5mm in AO, and the lowest value 4.7mm in APS. Angles between the wings proves the highest values $130.05^{\circ}$ in APS, and the lowest value $48.60^{\circ}$ in AU. Air dry weight of 20 seed-sets proves highest value 3,900mg, in AO, and the lowest value 404mg in AU. Viable seed ratio of AP proves 50%, and that of AU does 43.2%. Those of other four species ranges 8.6~22.2%. Considering postdispersal seed predators and disturbance of litter, viable seeds of APSM, AO, AM, and APS supplied in the natural forest in Korea might be insufficient for seedling establishment. This study showed that sound viable seed supply might be key factors of natural regeneration of major Acer species in Korea. The openings made by insect pests were observed on the seed-coat of APSM, AM, AU, and APS samara, and Bradybatus sharpi were observed in the samaras of APSM and AO. Further study on the seed insect fauna, pre- and post-dispersal seed viability, and annual variation on these factor should be needed.

• Restorative Dentistry and Endodontics
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• v.24 no.2
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• pp.265-285
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• 1999

The purposes of this investigation were to observe the reaction kinetics of five commercial dual cured resin cements (Bistite, Dual, Scotchbond, Duolink and Duo) when cured under varying thicknesses of porcelain inlays by chemical or light activation and to evaluate the effect of the porcelain disc on the rate of polymerization of dual cured resin cement during light exposure by using thermal analysis. Thermogravimetric analysis(TGA) was used to evaluate the weight change as a function of temperature during a thermal program from $25{\sim}800^{\circ}C$ at rate of $10^{\circ}C$/min and to measure inorganic filler weight %. Differential scanning calorimetry(DSC) was used to evaluate the heat of cure(${\Delta}H$), maximum rate of heat output and peak heat flow time in dual cured resin cement systems when the polymerization reaction occured by chemical cure only or by light exposure through 0mm, 1mm, 2mm and 4mm thickness of porcelain discs. In 4mm thickness of porcelain disc, the exposure time was varied from 40s to 60s to investigate the effect of the exposure time on polymerization reaction. To investigate the effect on the setting of dual cured resin cements of absorption of polymerizing light by porcelain materials used as inlays and onlays, the change of the intensity of the light attenuated by 1mm, 2mm and 4mm thickness of porcelain discs was measured using curing radiometer. The results were as follows 1. The heat of cure of resin cements was 34~60J/gm and significant differences were observed between brands (P<0.001). Inverse relationship was present between the heat of reaction and filler weight % the heat of cure decreased with increasing filler content (R=-0.967). The heat of reaction by light cure was greater than by chemical cure in Bistite, Scotchbond and Duolink(P<0.05), but there was no statistically significant difference in Dual and Duo(P>0.05). 2. The polymerization rate of chemical cure and light cure of five commercially available dual cured resin cements was found to vary greatly with brand. Setting time based on peak heat flow time was shortest in Duo during chemical cure, and shortest in Dual during light cure. Cure speed by light exposure was 5~20 times faster than by chemical cure in dual cured resin cements. The dual cured resin cements differed markedly in the ratio of light and chemical activated catalysts. 3. The peak heat flow time increased by 1.51, 1.87, and 3.24 times as light cure was done through 1mm, 2mm and 4mm thick porcelain discs. Exposure times recommended by the manufacturers were insufficient to compensate for the attenuation of light by the 4mm thick porcelain disc. 4. A strong inverse relationship was observed between peak heat flow and peak time in chemical cure(R=0.951), and a strong positive correlations hip was observed between peak heat flow and the heat of cure in light cure(R=0.928). There was no correlationship present between filler weight % or heat of cure and peak time. 5. The thermal decomposition of resin cements occured primarily between $300^{\circ}C$ and $480^{\circ}C$ with maximum decomposition rates at $335^{\circ}C$ and $440^{\circ}C$.

• Korean Journal of Remote Sensing
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• v.14 no.3
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• pp.296-306
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• 1998

Airborne MSS data is regarded as a potentially effective data source for the measurement of water quality and for the environmental change of water bodies. In this study, we measured the radiance reflectance by using multi-spectral image of low resolution camera(LRC) which will be reached in the multi-purpose satellite(KOMPSAT) to use the data in analyzing water pollution. We also investigated the possibility of extraction of water quality factors in water bodies by using high resolution remote sensing data such as Airborne MSS. Especially, we tried to extract environmental factors related with eutrophication such as chlorophyll-a, suspended sediments and turbidity, and also tried to develop the process technique and the radiance feature of reflectance related with eutrophication. Although it was difficult to explicitly correlate Airborne MSS data with water quality factors due to the insufficient number of ground truth data. The results were summarized as follows: First, the spectrum of sun's rays which reaches the surface of the earth was consistent with visible bands of 0.4${\mu}{\textrm}{m}$~0.7${\mu}{\textrm}{m}$ and about 50% of total quantity of radiation could be found. The spectrum was reached highest at around 0.5${\mu}{\textrm}{m}$ of green spectral band in visible bands. Second, as a result of the radiance reflectance Chlorophyll-a represented high mainly around 0.52${\mu}{\textrm}{m}$ of green spectral band, and suspended sediments and turbidity represented high at 0.8${\mu}{\textrm}{m}$ and at 0.57${\mu}{\textrm}{m}$, respectively. Finally, as a result of the water quality analysis by using Airborne MSS, Chlorophyll-a could have a distribution image after carrying out ratio of B3 and B5 to B7. Band 7 was useful for making the distribution image of suspended sediments. When we carried out PCA, suspended sediments and turbidity had distributions at PC 1 and PC 4 which are similar to the ground data. Above results can be changed according to the change of season and time. Therefore, in order to analyze the environmental factors of water quality by using LRC data more exactly, we need to investigate the ground data and the radiance feature of reflectance of water bodies constantly. For further studies, we will constantly analyze the radiance feature of the surface of water in wafter bodies by measuring the on-the-spot radiance reflectance and using low resolution satellite image(SeaWiFS). We will also gather the data of water quality analysis in water bodies and analyze the pattern of water pollution.