• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.438-445
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• 2017

Tanzania has abundant copper deposits, but copper-metal extraction remains low there, owing to the lack of suitable copper recovery processes and insufficient funds for developing mining technologies. Accordingly, leaching and solvent extraction methods for the extraction of copper from copper ore were studied with a particular emphasis on developing a simple processing method for small-scale copper mining. Chrysocolla ore was used as the copper-bearing mineral and sulfuric acid was used as the leaching reagent. A maximum copper recovery of 95.1% was obtained when the particles in the sample were smaller than $53{\mu}m$, the concentration of 98%(w/w) sulfuric acid in the leaching solution was 5.0 g/L and the stirring rate was between 60 and 80 rpm. The highest selectivity of $Cu^2+$ in the solvent extraction was obtained using 15% LIX-70 in kerosene. In the pH range from 0.5 to 3.0, the efficiency of $Cu^2+$ extraction increased with increasing pH. However, at pH values higher than 3.0, other metal ions were extracted into the organic phase more readily than $Cu^2+$. The highest solvent extraction rate obtained was 96.5% at pH values of 2.0 and 3.0 using 15% LIX-70.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.1
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• pp.76-84
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• 2015

This study aimed to investigate awareness of processed foods and chronic disease in high school students (male 94 and female 85) in the Yongin area. Awareness of chronic disease caused by excessive intake of processed foods was 83.0% and 91.8% in male and female students, and the most harmful processed food was instant noodles (34.1%). The most fearful chronic disease was cancer (25.5%) and obesity (25.5%) in males, whereas female answered obesity (34.1%). Awareness of synthetic preservatives was the most negative answer among food additives, and the most useful information was harmfulness of food additives. Percentages of correct answers towards cardiovascular disease-causing food components, including lipids, saturated fat, cholesterol, and trans fat, and dietary fiber for prevention of obesity were 57.0% and 54.2%, respectively. The percentage of correct answers towards developing hypertension by excessive intake of sodium was very low at 24.6%. Consequently, high school students generally showed a negative attitude towards processed foods without accurate information related to prevention or food components causing chronic disease, especially sodium. Thus, an appropriate program and persistent nutrition education are required for healthy food choices to prevent chronic disease among processed foods.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.1
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• pp.152-159
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• 2015

The purpose of this study was to analyze how consumers make links between convenience meat products and self-relevant consequences and value. Surveys on convenience meat product consumption patterns and hard laddering based on means-end chain theory were conducted from April 21 to April 25, 2014 and targeted 200 consumers in the US. The most preferred cooking method of convenience meat product was roast (25.9%) and the most common information medium was suggestions by friends and parents (37.1%). The main as well as desired places of purchasing were both the supermarket (33.6% and 27.3%, respectively). The most preferred promotion method was free sample events (38.5%). From analyzing means-end chains of convenience meat products, the most dominant value chain was 'taste (A)'-'good taste (C)'-'feel good (V)'. These results show that consumption of convenience meat products will increase when consumer expectations of taste and satisfaction are met. Further, results of the value measurement provide information on consumer satisfaction and needs and can be applied to set marketing strategies for Korean style convenience meat products.

• Journal of Obesity & Metabolic Syndrome
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• v.25 no.3
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• pp.138-148
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• 2016

Background: The purpose of this study is to analyze the effects of an abdominal obesity management program in middle-aged women in Korea. Methods: Examination of databases, including the Research Information Sharing Service, Database Periodical Information Academic, and Korean Studies Information, resulted in identification of 772 studies performed up to 2014, of which 43 satisfied the inclusion data. Data analysis was performed using R version 3.2 to calculate the effect sizes, explore possible causes of heterogeneity, and check for publication bias, using a funnel plot and its trim-and-fill analysis. Results: The mean effect size of the management program was small (g=0.22), along with the anthropometric index (g=0.18), metabolism index (g=0.21), fat-distribution (g=0.36), and inflammatory index (g=0.36). Moderator analysis was performed to determine heterogeneity, but no significant differences were found between the randomized controlled trial (RCT) group and non-RCT group. In addition, the length of the session was found to be statistically significant after performing a meta-regression. Finally, a funnel plot with a trim-and-fill analysis was produced to check for publication bias, but no significant bias was detected. Conclusion: Based on these findings, the abdominal obesity management program affects middle-aged women in Korea. Further research is needed to target other age groups with abdominal obesity.

• Food Engineering Progress
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• v.14 no.1
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• pp.49-53
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• 2010

Surface plasmon resonance (SPR) which is utilized in thin film refractometry-based sensors has been concerned on measurement of physical, chemical and biological quantities because of its high sensitivity and label-free feature. In this paper, an application of SPR to detection of alcohol content in wine and liquor was investigated. The result showed that SPR sensor had high potential to evaluate alcohol content. Nevertheless, food industry may need SPR sensor with higher sensitivity. Herein, we introduced a nano-technique into fabrication of SPR chip to enhance SPR sensitivity. Using Langmuir-Blodgett (LB) method, gold film with nano-structured surface was devised. In order to make a new SPR chip, firstly, a single layer of nano-scaled silica particles adhered to plain surface of gold film. Thereafter, gold was deposited on the template by an e-beam evaporator. Finally, the nano-structured surface with basin-like shape was obtained after removing the silica particles by sonication. In this study, two types of silica particles, or 130 nm and 300 nm, were used as template beads and sensitivity of the new SPR chip was tested with ethanol solution, respectively. Applying the new developed SPR sensor to a model food of alcoholic beverage, the sensitivity showed improvement of 95% over the conventional one.

• Journal of Korea Port Economic Association
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• v.30 no.1
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• pp.159-173
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• 2014

This study is key competence port logistics companies analyze the priorities of evaluation factors. key competence index of NCS(National competency standard) was designed on the basis of the research model. The priorities of evaluation factors were analyzed using AHP method. The results of the analysis of 1 layer's key competence priorities are as follows: Interpersonal skills(0.217), communication skills(0.153), ability to develop problem(0.148), ability to understand the organization(0.103), and resource management skills(0.090), self-development ability and professional ethics(0.070), information skills(0.065), technical skills(0.049), numeracy skills(0.035).

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.4
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• pp.431-441
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• 2021

Full-mouth rehabilitation with increasing vertical dimension can be used for patients with severely worn teeth. In severely worn teeth also, the alveolar process can be elongated to compensate for the reduced vertical dimension, and the patient's vertical dimension of occlusion can be kept constant. However, full-mouth rehabilitation with increasing vertical dimension must be carefully chosen, because the vertical dimension can be reduced by tooth wear. It is important to establish a treatment plan with the systematic diagnosis of the change in the vertical dimension and gain space for the prosthesis. It is necessary to change the vertical dimension to secure the restoration space and select the minimum vertical dimension elevation for the esthetic and functional goal. In this case report, the patient complained of difficulty during chewing due to a worn dentition and wanted esthetic improvement of the short mandibular anterior teeth. After systematic evaluation and diagnosis, we performed full-mouth rehabilitation with minimum vertical dimension elevation to obtain the space for restoration. This resulted in a stable and harmonious occlusion, and the functional and esthetic problems of the patient were solved after treatment. The patient was satisfied with the results of the treatment and maintained stable occlusion during the follow-up period.

• Korean Journal of Remote Sensing
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• v.37 no.5_3
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• pp.1425-1434
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• 2021

Continuous and periodic data acquisition must be preceded to maintain and manage the river facilities effectively. Adapting the existing general facilities methods, which include river surveying methods such as terrestrial laser scanners, total stations, and Global Navigation Satellite System (GNSS), has limitation in terms of its costs, manpower, and times to acquire spatial information since the river facilities are distributed across the wide and long area. On the other hand, the Mobile Mapping System (MMS) has comparative advantage in acquiring the data of river facilities since it constructs three-dimensional spatial information while moving. By using the MMS, 184,646,009 points could be attained for Anyang stream with a length of 4 kilometers only in 20 minutes. Levee points were divided at intervals of 10 meters so that about 378 levee cross sections were generated. In addition, the waterside maximum and average slope could be automatically calculated by separating slope plane form levee point cloud, and the accuracy of RMSE was confirmed by comparing with manually calculated slope. The reference slope was calculated manually by plotting point cloud of levee slope plane and selecting two points that use location information when calculating the slope. Also, as a result of comparing the water side slope with slope standard in basic river plan for Anyang stream, it is confirmed that inspecting the river facilities with the MMS point cloud is highly recommended than the existing river survey.

• Journal of Korean Elementary Science Education
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• v.40 no.3
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• pp.283-294
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• 2021

The purpose of this study is to examine the trends of science gifted education-related research for the last 5 years using LDA topic modeling. To achieve the purpose of the study, 2,404 keywords of 292 domestic academic papers were analyzed using RISS, KISS, and DBpia. The main results were as follows. First, the number of researches in science gifted education has been decreasing since 2019. In the science gifted education research, the top 10 keywords were 'students', 'program', 'elementary school', 'class', 'creativity', 'gifted education', 'awareness', 'teacher', 'education', and 'activity'. Second, as a result of topic modeling analysis, 10 topics were derived. Research topics mainly conducted in science gifted education for the past five years are 'Affective characteristics of science gifted students', 'Characteristics of science gifted students in middle school', 'Development and application of science gifted education programs', 'Education programs of science gifted high school', 'Cognitive characteristics of science gifted students', 'Policy of science gifted education', 'Science gifted students and creativity', 'Research conducting education by science gifted students', 'Academic and career choice of science gifted students', 'Science concept of science gifted Students'. In the past, the proportion of specific topics was relatively high, but the proportion between topics does not differ significantly as 2019 approaches. Therefore, it can be confirmed that the more recent it comes, the more research is being conducted evenly without being biased toward one subject.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.5
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• pp.180-187
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• 2021

Many young people, who are most affected by TV audition programs and the K-pop craze, have begun to choose careers in music. They attended music classes through academies or took private lessons, and then went on to a college's practical-music department. As the number of applicants increased, competition for university practical-music programs increased abnormally. As a result, many students then started learning music at an early age through private educational institutions and academies. Afterwards, as high schools related to practical music began to appear, the number of students entering practical-music high school and technical schools increased. However, a big problem in practical-music high schools was difficulty in finding professional teachers who majored in music. This arose because it was difficult for someone with a practical-music major to acquire a full-time teaching certificate. There are many ways to obtain a teacher's license, but the only option for practical-music majors is to graduate from the Graduate School of Education. However, since the Graduate School of Education is limited to classical and traditional music, admission itself is difficult. Even if someone is accepted by the school, most of the courses consist of classical music and traditional music education, which is very difficult for someone who majored in practical music. Therefore, in this thesis, we study the current situation in practical-music high schools, looking at why a regular Level 2 teaching certificate is needed and how to obtain one.