• Clean Technology
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• v.11 no.3
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• pp.123-128
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• 2005

Among various metal oxides semiconductors, $TiO_2$ is the most studied semiconductor for environmental clean-up applications due to its unique ability in photocatalyzing various organic contaminants, its chemical inertness, and nontoxicity. $TiO_2$, however, has a few drawbacks to be solved such as reactivity mainly working under ultraviolet irradiation (${\lambda}$ < 387 nm) and electron - hole recombination on $TiO_2$. In this study, to extend the absorption range of $TiO_2$ into the visible range and enhance electron - hole separation, we synthesized platinum (Pt) deposited $C-TiO_2$. The presence of Pt as an electron sink has been known to snhance the separation of photogenerated electron-hole pairs and induce the thermal decomposition. The characterization of as-synthesized $Pt-C-TiO_2$ was performed by Transmission Electron Microscopic (TEM), the Brunuer-Emmett-Teller (BET) method, X-ray Diffractometer (XRD), UV-vis spectrometer (UV-DRS), and X-ray Photoelectron Spectroscopy (XPS). In order to estimate the photocatalytic activity of the synthesized materials, the photoelectron Spectroscopy (XPS). In order to estimate the photocatalytic activity of the synthesized materials, the photodegradation experiment of an azo dye (Acid Red 44; $C_{10}H_7N=NC_{10}H_3(SO_3Na)_2OH$)was carried out by using an Xe arc lamp (300 W, Oriel). A 420 nm cut-off filter was used for visible light irradiation. From the results, Pt-deposited $C-TiO_2$ showed a far superior phothdegradation activity to Degussa P25, the commercial product under the irradiation of visible light and enhanced photocatalytic activity of visible-working $C-TiO_2$. This is a useful result into the application for the purification system of dye wastewater using visible energy of sun light.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.517-524
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• 2014

As an assessment of substantial equivalence and environmental risks of branchless chrysanthemum GM lines (LeLS69, LeLS76, LeLS80) developed in Korea, we investigated their degree of branchlessness and developmental characteristics including growth and flowering, as well as the stability of populations of insect pests and soil microbes. The GM lines were compared with a control variety, 'Jinba'. LeLS80 showed the highest level of branchlessness among the three GM lines, whereas abnormal axillary buds developed in lines LeLS76 and LeLS69. There were no significant differences between the growth characteristics of 'Jinba' and the GM lines. The branchlessness LeLS80 was increased during the summer season, suggesting that it is a useful germplasm for developing elite branchless cultivars. These GM lines showed no significant differences in the occurrence of five insect pests including aphids, mites, leaf miners, thrips, and whiteflies. Similarly, for soil microbes including bacteria and actinomycetes, there were no significant differences between 'Jinba' and the GM lines. However, there was a higher occurrence of fungi in the GM lines compared to 'Jinba'. Our findings suggest that 'Jinba' and the GM lines are substantially equivalent, although further monitoring studies are needed to confirm this.

• Journal of Animal Environmental Science
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• v.18 no.3
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• pp.247-256
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• 2012

This study was carried out to investigate the effects of various regions of sorghum-sorghum hybrid (SSH) silage on nutritive values and qualities of SSH silage. SSH "SS405" was harvested at ripen stage and ensiled. Samples of SSH silage used in this study were collected in three regions (outside, middle and inside). The contents of crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), total digestible nutrients (TDN) and in vitro dry matter digestibility (IVDMD) in SSH silage were not influenced by SSH silage manufacture methods and lactic acid bacteria. The contents of CP in inside region of SSH silage were lower than those of outside and middle regions (p<0.05). However, the contents of NDF, ADF and TDN, and IVDMD were not different between the regions of SSH silage. The content of lactic acid in SSH round bale silage was significantly decreased (p<0.05), as compared to SSH square bale silage (SB), gunny bag silage (GB) and trench silage (TS). The contents of acetic acid and butyric acid in SSH silage were not influenced by SSH silage manufacture methods and lactic acid bacteria. The contents of lactic acid in inside region of SSH silage were lower than those of outside and middle regions (p<0.05). In addition, the contents of lactic acid, acetic acid and butyric acid were not different between the regions of SSH silage. Therefore we suggest that nutritive values and quality of SSH silage were not influenced by regions of sampling collected from these silages.

• Journal of Science Education
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• v.32 no.2
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• pp.1-16
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• 2008

The purpose of this study was to analyze about STS contents in the next generation science textbook for 10th grade according to curriculum revision 2007 and high school science textbooks focused on the Earth Science which were published according to the 7th curriculum. The contents of STS were analyzed by the STS topics of Yager(1989), Piel's standard(1981), and student activities by SATIS. The results of this study are the same as follows: 'The next generation science textbook' was shown that 20.9% is STS material amount in average by Yager's standard. 'High school science textbooks' were shown that 11.3% is STS material amount in average. Based on the STS topics by Yager's standard, most of STS content is focused on 'Relativity with local community', 'Application of science' and 'Cooperative work on real problems'. However, there is rare contents such as 'Multiple dimensions of science', 'Practice with decision-making strategies' and 'Evaluation concerned for getting and using information' in the next generation science textbook. In high school science textbooks were shown that 'Applicability of science' is the highest and 'Relativity with local community' is the next high contents. Based on the STS topics by Piel's standard, most of STS contents are focused on 'Environmental quality', 'Space research' and 'National defence' in the next generation science textbook. But high school science textbooks are focused on 'Natural resources' and 'Technology development'. The activities were analyzed by SATIS student activities. The major categories of activities included in the next generation science textbook were 'Investigation', 'Simulation' and 'Data analysis'. But, there were rare activities like 'Roleplaying', 'Research design' and 'Simulation' in high school science textbooks.

• Journal of Soil and Groundwater Environment
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• v.12 no.5
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• pp.39-53
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• 2007

Generally, fractured medium can be described with some key parameters, such as hydraulic conductivities or random field of hydraulic conductivities (continuum model), spatial and statistical distribution of permeable fractures (discrete fracture network model). Investigating the practical applicability of the well-known conceptual models for the description of groundwater flow in fractured media, various types of hydraulic tests were applied to studies on the highly fractured media in Geumsan, Korea. Results from single-hole packer test show that the horizontal hydraulic conductivities in the permeable media are between $7.67{\times}10^{-10}{\sim}3.16{\times}10^{-6}$ m/sec, with $7.70{\times}10^{-7}$ m/sec arithmetic mean and $2.16{\times}10^{-7}$ m/sec geometric mean. Total number of test interval is 110 at 8 holes. The number of completely impermeable interval is 9, and the low permeable interval - below $1.0{\times}10^{-8}$ m/sec is 14. In other words, most of test intervals are permeable. The vertical distribution of hydraulic conductivities shows apparently the good correlation with the results of flowmeter test. But the results from the cross-hole test show some different features. The results from the cross-hole test are highly related to the connectivity and/or the binary properties of fractured media; permeable and impermeable. From the viewpoint of the connection, the application of the general stochastic approach with a single continuum model may not be appropriate even in the moderately or highly permeable fractured medium. Then, further studies on the investigation method and the analysis procedures should be required for the reasonable and practical design of the conceptual model, with which the binary properties, including permeable/impermeable features, can be described.

• Journal of Chest Surgery
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• v.35 no.5
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• pp.387-391
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• 2002

Background: Postoperative morbidity and mortality in destroyed lung are relatively high. We tried to identify the prognostic factors affecting postoperative morbidity and mortality in destroyed lung through a retrospective study. Material and method: The retrospective study was undertaken in 112 patients who had undergone pneumonectomy or pleuropneumonectomy for destroyed lung at Severance Hospital from 1970 to 2000. We analyzed the correlation between postoperative morbidity and mortality and etiology, duration of disease, preoperative FEV1, presence or absence of peroperative empyema, operation timing, the side of operation, duration of operation, and operation type. Result: There were 55 men and 57 women, aged 20 to 81 years (mean 44 years). Etiologic diseases were tuberculosis in 86 patients(76.8%) including tuberculos empyema in 20 and tuberculous bronchiectasis in 4, pyogenic empyema in 12(10,7%), bronchiectasis in 12(10.7%), and lung abscess in 2(1.8%). Postoperative morbidity were 25%(n=28) and postoperative mortality was 6%(n=7). The presence of preoperative empyema(p=0.016), pleuropneumonectomy(p=0.037) and preoperative FEV1 of less than 1.75 L(P=0.048) significantly increased the postoperative morbidity, If operation time was less than 300min, postoperative morbidity(p=0.002) and mortality(p=0.03) were significantly low. Conclusion: Postoperative morbidity and mortality in destroyed lung were acceptable. Postoperative morbidity and mortality were significantly low when operation time was less than 300 min. Preoperative existence of empyema, pleuropneumonectomy and preoperative FEV1 of less than 1.75 L significantly increased postoperative morbidity.

• Journal of agricultural medicine and community health
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• v.28 no.2
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• pp.155-169
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• 2003

Objectives: The purpose of this study is to provide data for the improvement of hypertension management of community health practitioner posts through the study on hypertension management in community health practitioner posts. Methods: A questionnaire was mailed to 700 community health practitioners and 205 of them responded during the period from March 13, 2003 to May 13. The survey results were analyzed using SPSS program, version 11. Results: The results are as follows; 1. There are two major activities in a hypertension prevention project for community: health education and early detection. About 57% of community health care practitioners perform a health education for community people four times a year. The 64.5% of them used the materials for health education provided from a community health center and 22.1% of them performed a post-evaluation. The main method of early detection of hypertension was measurement of blood pressure of person to visit, which was 96.1%. Other methods included home visiting(89.3%), a referral from community hospitals and other resources(49.1%), health promotion events(39.5%), and a review of medical records(35.7%). 2. For the registration and management of patients with hypertension, about 36% of community health centers used a special form and more than 50% of them have registered patients who were managed by other health care institutions in the community. A computerized program was used for the management of patients with hypertension in 68.5% of them. More than 60% of them responded that it was used for report, treatment, and follow-up of patients with hypertension.

• Neonatal Medicine
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• v.18 no.1
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• pp.137-142
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• 2011

Purpose: In relation to perinatal healthcare, medical institutions and resources are limitative and also are in a state of flux due to the therapeutic specialty. We analyzed requests for interhospital transfers received by Busan 1339 Emergency Medical Information Center (EMIC) to grasp the state of perinatal healthcare delivery system. Methods: This study was conducted on the basis of data inputted into the computing system of Busan 1339 EMIC, between January 1 and December 31, 2009. In connection with 378 pregnant women and 136 newborns who were required to transfer, retrospective analyses were made of the success rate of transfer (SR), the number of contacted hospitals, the time required for transfer and the reason of transfer and refusal. Results: In the case of pregnant women, the SR were 65.5%. They came in contact with 2.7 hospitals, and it took 24.4 minutes. As for the reason of transfer, preterm labor accounted for the highest proportion. In the case of newborns, the SR were 71.3%. They came in contact with 2.4 hospitals, and it took 15.6 minutes. The most common reason of transfer were respiratory symptoms. In the reason of refusal with pregnant women and newborn, the lack of medical staff, medical equipments and wards accounted for great. Conclusion: Many pregnant women and newborns have been transferred to hospitals by EMIC, but the SR has not been higher yet. Accordingly, there is a need to evaluate the propriety of perinatal treatment system, as well as to set up effective perinatal healthcare delivery system.

• Journal of Korean Society of Forest Science
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• v.87 no.3
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• pp.358-365
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• 1998

To offer the basic information for sustainable production of forest resources and conservation of the global environment, change in potential natural vegetation (PNV) associated with climate change due to doubling atmospheric carbon dioxide ($2{\times}CO_2$) was estimated with the global natural vegetation mapping system based an K${\ddot{o}}$ppen scheme. The system interpolates climate data spherically to each grid cell, determines the vegetation types onto the grid cell, and produces potential vegetation map and area on the globe and continents. The climate data consist of the current, ($1{\times}CO_2$) climate prior to AD 1958 observed at some 2,000 stations and the doubling ($2{\times}CO_2$) climate estimated from Meteorological Research Institute of Japan. The vegetation zone under the $2{\times}CO_2$ climate scenario expanded mainly toward the poles due to the rise in temperature. The changed PNV area on the globe amounts to 1/3 (4.91 billion (G) ha) of the total land area (15.04 Gha). Kappa statistic for judging agreement between the patterns of vegetation distribution under $1{\times}CO_2$ climate and $2{\times}CO_2$ climates shows good agreement (0.63) for the globe as a whole. The most stable areas are desert and ice. The potential forest area (PFA) was estimated at 6.82 Gha of the land area in $2{\times}CO_2$ climate scenario. In terms of continental changes in PFA, North America and Asis are increased under the $2{\times}CO_2$ climate. However, the potential forest arms of the other continents are decreased by the climate. Europe has no change in the PFA. Especially, the expansion of desert area in Oceania would be accelerated by the $2{\times}CO_2$ climate.

• Knowledge Management Research
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• v.21 no.3
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• pp.249-269
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• 2020

Recently, as the online market has matured, it is facing many problems to prevent the growth. The most common problem is the homogenization of online products, which fails to increase the number of customers any more. Moreover, although the portion of the online market has increased significantly, it now becomes essential to expand offline for further development. In response, many online firms have recently sought to expand their businesses and marketing channels by securing offline spaces that can complement the limitations of online platforms, on top of their existing advantages of online channels. Based on their competitive advantage in terms of analyzing large volumes of customer data utilizing information technologies (e.g., big data and artificial intelligence), they are reinforcing their offline influence as well through this online for offline (O4O) business model. On the other hand, most of the existing research has primarily focused on online to offline (O2O) business model, and there is still a lack of research on O4O business models, which have been actively attempted in various industrial fields in recent years. Since a few of O4O-related studies have been conducted only in an experience marketing setting following a case study method, it is critical to conduct an empirical study on O4O selection attributes and their impact on customer satisfaction and loyalty. Therefore, focusing on China's representative O4O business model, 'Fresh Hema,' this study attempts to identify some key selection attributes specialized for O4O services from the customers' viewpoint and examine the impact of these attributes on customer satisfaction and loyalty. The results of the structural equation modeling (SEM) with 300 O4O (Fresh Hema) experienced customers, reveal that, out of seven O4O selection attributes, four (mobile app quality, mobile payment, product quality, and store facilities) have an impact on customer satisfaction, which also leads to customer loyalty (reuse intention, recommendation intention, and brand attachment). This study would help managers in an O4O area well adapt to rapidly changing customer needs and provide them with some guidelines for enhancing both customer satisfaction and loyalty by allocating more resources to more significant selection attributes, rather than less significant ones.