• Journal of Environmental Health Sciences
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• v.43 no.3
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• pp.176-184
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• 2017

Objectives: Excluding in their homes, children spend most of their time at an elementary school, daycare center, and/or kindergarten. For educational or recreational purposes, they make use of many children's goods at these places. Some children's goods contain phthalates and heavy metals with polyvinyl chloride (PVC), so due to their physiological and behavioral characteristics children are exposed to high concentrations of phthalates and heavy metals. This study aims to measure PVC and heavy metals, which are harmful substances in children's goods which can have an effect on children's health. Methods: Six samples of children's goods were selected through cases of detected harmful substances and the results of previous research, including assembly blocks, model toys, household toys, bags, indoor play equipment, and floor mats. The selected items were measured using X-Ray Fluorescence (XRF), and the presence and content of environmentally harmful substances such as PVC or heavy metals in the materials of children's goods were examined. Results: The highest detection rate for PVC was observed in floor mats, and bags and indoor play equipment were higher than other goods in this regard. The highest detection rate for heavy metals was found in bags, followed by indoor play equipment, assembly blocks, household toys, model toys and floor mats. Except for bags containing heavy metals, five goods showed the highest level of Pb compared to other heavy metals. Floor mats contained the highest level of Pb, Cr, and Cu among all goods. Conclusion: Many children's goods contain PVC and heavy metals, and high levels of heavy metals have been detected in some goods. It is necessary to manage children's goods to support their health.

• Journal of Convergence for Information Technology
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• v.7 no.6
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• pp.113-121
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• 2017

Due to the development of IT technology, harmful multimedia contents are spreading out. In addition, obscene and violent contents have a negative impact on children. Therefore, in this paper, we propose a multimodal approach for blocking obscene and violent video contents. Within this approach, there are two modules each detects obsceneness and violence. In the obsceneness module, there is a model that detects obsceneness based on adult and racy score. In the violence module, there are two models for detecting violence: one is the blood detection model using RGB region and the other is motion extraction model for observation that violent actions have larger magnitude and direction change. Through result of these three models, this approach judges whether or not the content is harmful. This can contribute to the blocking obscene and violent contents that are distributed indiscriminately.

• Journal of the Korea Society of Computer and Information
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• v.25 no.12
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• pp.127-134
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• 2020

Recently, Harmful sites, including pornographic videos, drugs, personal information and hacking tool distribution sites, have caused serious social problems. However, due to the nature of the Internet environment where anyone can use it freely, it is difficult to control the user effectively. And the site operator operates by changing the domain to bypass the blockage. Therefore, even once identified sites have low persistence. In this paper, we propose multi-channel domain tracking technology, a technique that can effectively track changes in the domain addresses of harmful sites, including the same or similar content, by tracking changes in these harmful sites. Proposed technology is a technology that can continuously track information in a domain using OSINT technology. We tested and verified that the proposed technology was effective for domain tracking with a 90.4% trace rate (sensing 66 changes out of 73 domains).

• Environmental Engineering Research
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• v.21 no.2
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• pp.145-151
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• 2016

Biodrying is a pre-treatment method that applies biological and mechanical concepts to drying solid waste. In Malaysia, municipal solid waste (MSW) is unseparated and contains a high level of moisture, making the use of technology such as solid waste burning unsuitable and harmful. MSW containing organic material can be processed naturally until the moisture content of the waste is reduced. This study on MSW biodrying was carried out on a laboratory scale to measure the percent moisture content reduction and to monitor temperature patterns under different ventilation periods. This work was conducted using five biodrying reactors volumes of 50 liters each. Reactors were ventilated for 5, 10, 15, 20 and 30 min every 3 h, with a 3 bar air supply. The duration of this process was 14 days for all samples. The results showed that the optimum ventilation time was 10 min, with an 81.84% reduction in moisture content, and that it required almost half of the electricity cost required for the 20 and 30 min ventilations.

• English Language & Literature Teaching
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• v.16 no.4
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• pp.133-152
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• 2010

There is disagreement, among researchers, on the benefits of corrective feedback on L2 learners' written output. Some scholars advocate the usefulness of corrective feedback while some claim that error correction is ineffective and even harmful. So far, however, research outcomes cannot settle this debate. Based on this debate, this study examines whether there is a difference among diverse types of feedback on the effects of L2 learners' writing improvement. This study found that teacher's direct feedback was more effective than any other types of feedback on the effect of participants' writing improvement. In particular, teacher's direct feedback helped their improvement on grammar, mechanics, and form. Among the types of peer feedback, self-correction was the most effective. In teacher feedback, form-focused feedback had more effects than content-focused feedback, but no difference with regard to peer feedback. In addition, teacher's content-focused feedback was more effective than peer's content-focused feedback. Overall, in all types of feedback, teacher feedback was more effective than peer feedback. However, direct (form-focused) feedback was the most effective in teacher feedback, and self-correction in peer feedback. The least effective feedback in both teacher and peer feedback was indirect (form-focused) feedback, which is simple underlining of errors.

• Journal of Ginseng Research
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• v.42 no.1
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• pp.21-26
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• 2018

Background: Furosine (${\varepsilon}$-N-2-furoylmethyl-L-lysine, FML) is an amino acid derivative, which is considered to be an important indicator of the extent of damage (deteriorating the quality of amino acid and proteins due to a blockage of lysine and a decrease in the digestibility of proteins) during the early stages of the Maillard reaction. In addition, FML has been proven to be harmful because it is closely related to a variety of diseases such as diabetes. The qualitative analysis of FML in fresh and processed ginsengs was confirmed using HPLC-MS. Methods: An ion-pair reversed-phase LC method was used for the quantitative analysis of FML in various ginseng samples. Results: The contents of FML in the ginseng samples were 3.35-42.28 g/kg protein. The lowest value was observed in the freshly collected ginseng samples, and the highest value was found in the black ginseng concentrate. Heat treatment and honey addition significantly increased the FML content from 3.35 g/kg protein to 42.28 g/kg protein. Conclusion: These results indicate that FML is a promising indicator to estimate the heat treatment degree and honey addition level during the manufacture of ginseng products. The FML content is also an important parameter to identity the quality of ginseng products. In addition, the generation and regulation of potentially harmful Maillard reaction products-FML in ginseng processing was also investigated, providing a solid theoretical foundation and valuable reference for safe ginseng processing.

• Journal of Life Science
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• v.11 no.2
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• pp.74-80
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• 2001

The nucleotide sequences of the internal transcribed spacer regions (ITS1 and ITS2) of ribosomal DNA (rDNA), and the 5.85 rRNA gene, have been determined for 13 strains of dinoflagellates in order to analyze the phylo-genetic relationship. The DNA sequences contained considerable variation in the ITS regions, but little in the 5.85 rDNA. In addition, the ITS1 was more variable than the ITS2 in all species examined. The nucleotide length of this region varied from 519 bp to 596 bp depending on the taxa. The investigated taxa were divided into three large groups based on the ITS length, i. e., a group with short ITS region (A. fraterculus and Alexandrium sp.), a with ITS region group (P. micans, P. minimum and P. triestinum) and a with ITS region group (G. impudicum, C. polykrikoides, G. sanguineum, G. catenatum and H. triquetra). The relationship between nucleotide length of ITS1 and that of ITS2 was negative, whereas G+C content and nucleotide length showed positive correlation. In phylogenetic analyses producing NJ trees, the topology was similar cluster and clearly divided the taxa into three groups based on 5.8S rDNA that were similar to those based on morphological characteristics. In particular, G. impudicum was more closely related to G. catenatum than to C. polykrikoides using phylogenetic analysis. From this study, we chew that the length of ITS region contributes to discriminate Korean harmful algal species and ITS analysis is a useful method for resolving the systematic relationships of dinoflagellates.

• The Korean Fashion and Textile Research Journal
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• v.23 no.6
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• pp.844-851
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• 2021

Due to the increase in consumers' interest about well-being, interest in eco-friendly products has been increasing due to the harmful effects of various harmful substances contained in textile products and environmental issues. As a result, natural dyes of less potential risk than synthetic dyes and digital textile printing(DTP) textile products with less environmental pollution are drawing attention. However, due to the lack of evaluation criteria for DTP textile products with natural ink and the nature of many colors are stacked layer by layer for dying, the need for simultaneous analysis is emerging. To evaluate whether the natural dye is derived from natural ingredients, the biocarbon content is analyzed. However, in the case of ink made using natural dyes and DTP textile products using natural ink, it is difficult to analyze the biocarbon content due to the limitation of the presence of a small amount of dye contained therein. In this study, we were shown the possibility of natural derived verification by cross-checking the analytes of natural dyes (Persicaria tinctoria, an indigo dye; Dactylopius coccus, a light red; and Curcum longa L., i.e., turmeric) and natural ink with HPLC-MS/MS. The coefficient of determination was 0.999 or higher, the limit of quantification was 0.647-3.664 ㎍/L and a %RSD of each indicator material was less than 10. Then, the extraction amount of natural dyes for five patterned fabrics was analyzed.

• The Journal of the Korea Contents Association
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• v.4 no.2
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• pp.1-6
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• 2004

This paper proposes on the acoustic signal processing blocking method of Internet pornographicl sites by calculating correlation values between prototype acoustic signals and input acoustic signals. Pre-existing blocking methods mainly focused on directory-based bled(fin and pornographic related words-based blocking. But these methods are not completely blocked the Internet harmful pornographicl sites by several situations. For this, this paper proposes the content-based blocking method which composes of the image-based blocking and the acoustic-based blocking. This paper, mainly, deals with the acoustic -based blocking method. Finally, the effectiveness of this system is demonstrated by several experiments.

• Annual Conference of KIPS
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• 2002.11c
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• pp.2355-2358
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• 2002

인터넷의 급격한 보급으로 음란외설 폭력정보와 같은 불건전 정보가 날로 증가하고 있으며 이러한 유해정보로 인해 청소년들에게 심각한 사회적인 문제를 초래하고 있다. 이에 따라, 본 논문에서는 기존의 보편화된 차단방식의 문제점을 해소하기 위해 등장한 인터넷 내용 등급제를 비교분석하고, 정보통신윤리위원회에서 제시한 등급기준을 토대로 PICS(Platform for Internet Content Selection) 기반의 선별 프로그램을 구현하고, 기존 차단 프로그램과 성능을 비교 평가하였다. 구현된 프로그램은 현재 실용화되는 기술과의 호환성을 유지하도록 시스템을 구성하였다.