• Journal of Environmental Health Sciences
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• v.40 no.3
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• pp.178-186
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• 2014

Background: This study was conducted to assess health risks in regard to exposure by children to volatile organic compounds (VOCs) in children's products. Methods: Ten VOCs were measured by head-space gas chromatography in children's products, including toys, oil pastels, sign pens, furniture, ball pools, and playmats. We estimated the average daily dose (ADD) via inhalation during the use of these children's products and calculated hazard quotient (HQ) by dividing ADD by reference dose of VOCs. Results: Among the measured VOCs, five compounds were identified in children's products: benzene, ethylbenzene, styrene, toluene, and xylene. The detection rates of VOCs in toys, ball pools, furniture, playmats, sign pens, and oil pastels were 85%, 100%, 100%, 30%, 100%, and 60%, respectively. The maximum levels of VOCs were 0.18 mg benzene/kg in toys, 5.92 mg toluene/kg in playmats, 10.37 mg ethylbenzene/kg in ball pools, 24.85 mg xylene/kg in toys, and 118.29 mg styrene/kg in ball pools. From exposure levels of VOCs in the children's products HQs were calculated within a range of $5.71{\times}10^{-10}$ to $4.77{\times}10^{-4}$. The HQ of xylene was the highest for children aged 0-6 playing on the playmats. However, the HQ via inhalation exposure to VOCs in individual products did not exceed 1.00. Conclusion: Based on the results, it was concluded that the use of these children's products do not pose health risks to children.

• Journal of Broadcast Engineering
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• v.12 no.6
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• pp.574-584
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• 2007

As the real time multimedia service become more popular, the needs of transmission with low delay and high quality are getting more stronger. Among those video compression technologies, the rate control method dose an important role in getting the effective data transmitting and the high image quality. In this paper, we combined the feature of CBR and VBR coding methods to propose a new bit-rate control method witch allows each frame to generates bits in the defined fluctuation range and applies a scene change detection at a part of frame and also can maintain low-delay and high quality even if the perfect VBR transmission environment is not guaranteed. The experiment result shows the proposed algorithm provides more effective method than TMN8 in real time application.

• Journal of Convergence for Information Technology
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• v.11 no.5
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• pp.118-129
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• 2021

The In Korea, where multicultural families are increasing, the need to reinforce multicultural competencies has been raised in education. Accordingly, this study selected 7 art textbooks of 2015 revised middle school and analyzed the proportion of the textbook's reference works and contents from the Macfee's perspective of multicultural education. As a result of the analysis, first, the proportion of multicultural reference works by region was high in Korean works(44%) and Western works (43%), whereas that of Eastern works(13%) was very low. In the experience area, 13.8% more Western works were included than Korean works, and Western works were also concentrated in USA and Europe. Second, as a result of analyzing the proportion of multicultural contents, 57.7% of the total units, or 90 units out of 156, contained multicultural contents. As a result, compared to the 2009 revised art textbooks, the 2015 revised middle school art textbooks have expanded the proportion of multiculturalism.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.21 no.2
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• pp.149-156
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• 2011

In the recent years, power analysis attacks were widely investigated, and so various countermeasures have been proposed. In the case of block ciphers, masking methods that blind the intermediate values in the en/decryption computations are well-known among these countermeasures. But the cost of non-linear part is extremely high in the masking method of block cipher, and so the countermeasure for S-box must be efficiently constructed in the case of AES, ARIA and SEED. Existing countermeasures for S-box use the masked S-box table to require 256 bytes RAM corresponding to one S-box. But, the usage of the these countermeasures is not adequate in the lightweight security devices having the small size of RAM. In this paper, we propose the new countermeasure not using the masked S-box table to make up for this weak point. Also, the new countermeasure reduces time-complexity as well as the usage of RAM because this does not consume the time for generating masked S-box table.

• Applied Microscopy
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• v.35 no.1
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• pp.31-39
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• 2005

Synapses are contact points where one neuron communicates with another. The morphological change of synapses under various physiological or pathological conditions has long been hypothesized to modify their functional properties. 3-dimensional (3-D) reconstruction of synapses with serial ultrathin sections has contributed to the understanding of ultrastructural dimensions and compositions of synapses. The 3-D reconstruction procedures, however, require a great amount of expertise as well as include prohibitively timeconsuming processes. Here, we introduce efficient 3-D reconstruction technique using high-voltage electron microscopy (HVEM). Primarily, we established an optimal section thickness and staining condition to observe synaptic structures in detail under HVEM. The result showed that synaptic profiles were preserved at the section thickness of 250 nm without the overlapping of synaptic ultrastructures. An increase in the reaction time of en bloc staining was most efficient to enhance contrast than the extension of postembedding staining or the addition of uranyl acetate during dehydration. Then, 3-D reconstruction of parallel fiber-Purkinje cell synapses in the rat cerebellum was carried out with serial HVEM images and reconstruction software. The images were aligned and the contours of synapses were outlined on each section. 3-D synapses were finally extracted from the section files by grouping all the synaptic contours. The reconstructed synapse model clearly demonstrated the configuration of pre and postsynaptic components. These results suggest that 3-D reconstruction of synapses using HVEM is much efficient and suitable for massive quantitative studies on synaptic connectivity than conventional TEM approach using numerous ultrathin sections.

• Food Science of Animal Resources
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• v.28 no.5
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• pp.555-561
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• 2008

Ninety-nine samples of powdered infant formula in a market were collected from the local market and their contaminations for total aerobic bacteria, coliform, FAO/WHO Category A, B, and C pathogens were analyzed. Total aerobic bacteria were detected in 92 of 99 samples (93%) at levels of $1.83{\pm}0.68\;Log\;MPN/g$. These levels were below legal levels specified for infant formulas except for one sample detected by 4.5 Log CFU/g. Coliform was detected in 12 of 99 samples (12%) at levels of $1.26{\pm}1.03\;Log\;MPN/g$ whereas non-detection was required according to the specification of coliform in infant formulas. Escherichia coli was detected in 1 of 99 samples by 0.48 Log MPN/g. Salmonella and Enterobacter sakazakii among Category A weren't detected in all the samples. Enterobacteriaceae, Category B group, were detected in 25 samples of total 99 samples (25%) by $0.83{\pm}1.37\;Log\;MPN/g$. Enterobacteriaceae identified by API 20E were Escherichia vulneris, Es. hermannii, Pantoea spp., Citrobacter koseri, Klebsiella pneumoniae, En. cloaceae. Bacillus cereus among Category C was highly detected in 29 of 99 samples (29%) at levels of $0.69{\pm}0.32\;Log\;MPN/g$ with the most probable number count method, which were below legal levels for the specification of B. cereus in infant formulas. Clostridium perfringens, E. coli O157, Staphyloccus aureus, Listeria monocytogenes, Yersinia enterocolitica, and Campylobacter jejuni/coli were not detected. Contamination level of major pathogens was low and falls within the range of specification of infant formulas. However, Enterobacteriaceae and B.cereus showed the high prevalence and some Enterobacteriaceae causing disease were detected. Therefore, it is necessary to monitor the potential pathogens continually and reduce them to improve the microbial quality of non-sterilized powdered infant formulas.

• Bioinformatics and Biosystems
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• v.1 no.2
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• pp.134-138
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• 2006

Depression is the most common and widespread mood disorder. About 20% of the population might suffer a major, incapacitating episode of depression during their lifetime. This disorder can be classified into two types: major depressive disorders and bipolar disorder. Since pharmaceutical treatments are different according to types of depression disorders, correct and fast classification is quite critical for depression patients. Yet, classical statistical method, such as minnesota multiphasic personality inventory (MMPI), have some difficulties in applying to depression patients, because the patients suffer from concentration. We used electroencephalogram (EEG) analysis method fer classification of depression. We extracted nonlinearity of information flows between channels and estimated approximate entropy (ApEn) for the EEG at each channel. Using these attributes, we applied two types of data mining classification methods: decision tree and possibilistic support vector machines (PSVM). We found that decision tree showed 85.19% accuracy and PSVM exhibited 77.78% accuracy for classification of depression, 30 patients with major depressive disorder and 24 patients having bipolar disorder.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.1
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• pp.119-128
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• 2016

Urban park planning has become difficult due to the lack of municipal funds. Thereupon, a special scheme was imposed for city park planning. Since then, a legal amendment was made for economical improvement and more active participation. However, there are a lot of questions about whether it was a suitable direction for parks and where it should be emphasized for public interest. Base on these concerns, this study examined the basis and characteristics of location, creation, and maintenance of private development parks in Japan, which was the policy model of Korean private parks. Location and space planning of private development parks was made up considering an effective green network and disaster prevention function, and a minimum area was about 1.42ha. The minimum area, 1ha, was established on the basis of considering realistic possibilities, disaster protection, and universal validity. It was also amended to consider the standard of type two mid- to high-rise exclusive residential areas and consultation with regional governance. Finally, it was built on the lowest limit of ordinance of the relevant city; for example, 100% of the floor area ratio, 30% of the building coverage ratio, and the maximum height of 11 stories, etc. For maintenance, private and public sectors were working together. Maintenance fees for 35 years (based on $300yen/m^2$ per month) were paid en bloc by the licensee. However, the city was paid for facilities that accompanied excessive maintenance costs. Meanwhile, it seemed difficult to introduce attractive profit facilities because of the limitations in location, usage permission, and introduction equipment; furthermore, there were problems with management authority, and the burden of expenses was deducted. For creating private Korean parks, this study suggested that we should build priority of creating city parks and select appropriate locations first; also, we need to make criteria for location, creation, and standard management rules that are relevant to the whole nation of Korea.

• Radiation Oncology Journal
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• v.8 no.2
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• pp.177-182
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• 1990

From 1984 to 1988, fourty two patients with nasopharyngeal cancer were treated at the Department of Radiation Oncology in Kyungpook National University Hospital. Thirteen patients refused treatment and the median survival time was 7.8 months. Twenty nine patients received a full course of radiation at least 70 Gy to the primary site and 60 Gy to the nodal sites. These patients were all belonged to stage III or IV, The local control rate was $75\% in squamous cell carcinomas, and all the patients with lymphoepithelioma showed a complete response. Overall locoregional failure was $27.6\%. Distant metastasis was the predominant pattern of failures; 4/6 in lymphoepithelioma, 4/10 En squamous cell carcinoma. The Three-year-survival rate for squamous cell carcinoma was $40.5\%$, and for lymphoepithelioma $25.9\%, respectively. This may be due to the more frequent distant metastases in lymphoepithelioma and ineffective chemotherapy. No survival correlation was found with the level of neck node involvement. Though adjuvant chemotherapy was found to be of no benefit in overall survival, more prudent and aggressive chemotherapy would be necessary.

• Korean Journal of Environmental Biology
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• v.21 no.2
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• pp.170-176
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• 2003

The effect of xenobiotics on cytochrome P450 (CYP) and 7-ethoxyresorufin-O-deethylase (EROD) in hepatopancreatic microsome of surf clam, Coelomactra anti-quata, were investigated. The microsome isolated from the digestive gland of the surf clam, collected from the east coast of Korea, was in vitro exposed to p, p -DDT (0.1,0.4 and 1.0 mM) for 30 min and 2,3,7,8-TCDD (0.01, 0.04 and 0.1 ppb) and PCB-153 (0.01, 0.04 and 0.1 ppb) for 7 hr. In the case of DDT exposure, the CYP content and EROD activity of 1.0 mM exposure group increased up to about 117% and 120% of the DMSO solvent control group after 10 min. exposure, respectively. After 2 hr exposure of TCDD, the CYP content and EROD activity were also induced to the range of 103∼110% and 121∼139%, respectively. The PCB-153 exposure group showed 107∼115% of CYP content and 129∼140% of EROD activity after 2 hr exposure. Three test chemicals apparently induced CYP and EROD activity in the microsome of surf clam. The inducing potentials depend en the test chemicals.