• Journal of The Korean Association For Science Education
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• v.41 no.6
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• pp.471-481
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• 2021

The importance of science education for cultivating the competencies required by an intelligent information society is gradually being strengthened. The government's roles and responsibilities for science education are stipulated by laws and policies in Korea. In order to systematically support science education, continuous monitoring of related policies is essential. This study aims to develop indicators that can be used to systematically and continuously monitor the national policies on science education in Korea. To achieve this goal, we first derive the framework for the indicators that has two dimensions (learner and science education context) and three categories (input, process, and outcome) from literature reviews. In order to derive the components and subcomponents of the indicators, the contents of science education-related indicators developed in Korea or abroad were reviewed. In order to verify the suitability and validity of the framework and components of the initial indicators, a two-round Delphi method was conducted with 25 expert participants with five different professions in science education. Finally, three components of the 'input' category (student characteristics, teacher characteristics, and educational infrastructure), three components of the 'process' category (science curriculum implementation, science educational contents and programs implementation, and teacher professional development program implementation), and five components of the 'outcome' category (science competency, participation and action, affective achievement, cognitive achievement, and satisfaction) were derived. An instrument to collect data from students, teachers, and institutions was developed based on the components and subcomponents, and content validity and internal consistency of the instrument were analyzed. Korea's Science Education Indicators developed in this study can comprehensively measure the current status of science education and is expected to contribute to a more efficient and effective science education policy planning and implementation.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.24 no.3
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• pp.97-106
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• 2018

This study aimed at examining the suitability of $Tenax^{(R)}$ for the migration testing of food packaging materials, which is currently approved in the EU as a dry food simulant. The results are used as a basis to examine the feasibility of introducing $Tenax^{(R)}$ to Korean regulation. The OMVs of test specimen into various solvents (diethyl ether, ethanol, pentane, and acetone) after exposure to $100^{\circ}C$ for 1 hr were compared. Diethyl ether showed the highest OMV ($1.33mg/dm^2$) among the solvents tested. When the tests were conducted with different amounts of $Tenax^{(R)}$ of 2, 4, or 8 g per specimen, the OMVs were 0.75, 1.33 and $1.40mg/dm^2$, respectively. The OMV obtained with a closed system after wrapping with aluminum foil showed a significantly higher OMV ($1.61mg/dm^2$) than that without aluminum wrapping ($1.318mg/dm^2w$) and an open system without lid ($1.06mg/dm^2$). The specific migration rates of surrogates spiked in the polyethylene test film and paper samples into $Tenax^{(R)}$ were compared with those into liquid food simulants including 95% ethanol and n-heptane, and actual foods such as starch, skim milk, and sugar. In general, the specific migration levels of surrogates into $Tenax^{(R)}$ were similar compared with n-heptane, however those were significantly higher than into actual foods. These results suggest that $Tenax^{(R)}$ may be used as a food simulant for the long-term preservation of dried foods and paper products. However, more studies need to be conducted to investigate the factors influencing the migration into $Tenax^{(R)}$, such as the types of foods and packaging materials tested, migration conditions, and surrogates properties etc.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.2
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• pp.59-75
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• 2019

This study was carried out to explore the 4th Industrial Revolution technology from the perspective of the landscape industry to provide the basic data necessary to increase the virtuous circle value. The 4th Industrial Revolution, the characteristics of the landscape industry and urban regeneration were considered and the methodology was established and studied including the technical classification system suitable for systematic research, which was selected as a framework. First, the 4th Industrial Revolution technology based on digital data was selected, which could be utilized to increase the value of the virtuous circle for the landscape industry. From 'Element Technology Level', and 'Core Technology' such as the Internet of Things, Cloud Computing, Big Data, Artificial Intelligence, Robot, 'Peripheral Technology', Virtual or Augmented Reality, Drones, 3D 4D Printing, and 3D Scanning were highlighted as the 4th Industrial Revolution technology. It has been shown that it is possible to increase the value of the virtuous circle when applied at the 'Trend Level', in particular to the landscape industry. The 'System Level' was analyzed as a general-purpose technology, and based on the platform, the level of element technology(computers, and smart devices) was systematically interconnected, and illuminated with the 4th Industrial Revolution technology based on digital data. The application of the 'Trend Level' specific to the landscape industry has been shown to be an effective technology for increasing the virtuous circle values. It is possible to realize all synergistic effects and implementation of the proposed method at the trend level applying the element technology level. Smart gardens, smart parks, etc. have been analyzed to the level they should pursue. It was judged that Smart City, Smart Home, Smart Farm, and Precision Agriculture, Smart Tourism, and Smart Health Care could be highly linked through the collaboration among technologies in adjacent areas at the Trend Level. Additionally, various utilization measures of related technology applied at the Trend Level were highlighted in the process of urban regeneration, public service space creation, maintenance, and public service. In other words, with the realization of ubiquitous computing, Hyper-Connectivity, Hyper-Reality, Hyper-Intelligence, and Hyper-Convergence were proposed, reflecting the basic characteristics of digital technology in the landscape industry can be achieved. It was analyzed that the landscaping industry was effectively accommodating and coordinating with the needs of new characters, education and consulting, as well as existing tasks, even when participating in urban regeneration projects. In particular, it has been shown that the overall landscapig area is effective in increasing the virtuous circle value when it systems the related technology at the trend level by linking maintenance with strategic bridgehead. This is because the industrial structure is effective in distributing data and information produced from various channels. Subsequent research, such as demonstrating the fusion of the 4th Industrial Revolution technology based on the use of digital data in creation, maintenance, and service of actual landscape space is necessary.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.740-748
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• 2018

This study was conducted to investigate the effects of dietary supplementation of enzyme complex (metalloprotease and xylanase) on growth performance, carcass characteristics and meat storability of broiler chickens. The experiment utilized a 2 (basal and low spec diets) ${\times}$ 3 (0, 0.5 or 1 g/kg of enzyme supplementation) factorial arrangement. A total of 360 male Ross broilers were randomly assigned into the following six groups: BD-T0 (basal diet + enzyme complex 0 g/kg), BD-T1 (basal diet + enzyme complex 0.5 g/kg), BD-T2 (basal diet + enzyme complex 1 g/kg), LD-T0 (low spec diet + enzyme complex 0 g/kg), LD-T1 (low spec diet + enzyme complex 0.5 g/kg), LD-T2 (low spec diet + enzyme complex 1 g/kg). Feed and water were provided ad libitum for 42 days, during which time feed intake and body weight were measured at one-week intervals. After the feeding trial, chickens were slaughtered by exsanguination and samples were collected. Feed intake was lower in the enzyme supplemented groups than the non-supplemented groups (p<0.05), as were body weight and gain (p<0.05). Thus, the feed conversion ratio improved in the enzyme supplemented groups relative to the non-supplemented groups (p<0.05). The carcass rate and production index were also significantly improved by supplementation with enzyme complex (p<0.05). Finally, the thiobarbituric acid reactive substances (TBARS) values were lower in the enzyme supplementation groups after 6 storage days (p<0.05). In conclusion, dietary supplementation with enzyme complex including metalloprotease and xylanase improved growth performance, carcass characteristics, and storability of broiler chicken meat.

• Journal of the Korean Institute of Landscape Architecture
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• v.49 no.5
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• pp.151-162
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• 2021

The recent trend of using ornamental grasses as essential landscaping plants has become more prominent, while the demands for today's gardens are to solve the challenges of climate change, biodiversity loss, and urban ecosystem services. Nowadays, the interest in ornamental grasses in South Korea is dramatically increasing, as is the number of available species and varieties. To find the better use of ornamental grasses in urban green spaces, more research should be conducted to understand the current state of ornamental grasses and their characteristics in South Korea. and a practical way of applying ornamental grasses to urban gardens should be devised. For that purpose, this research carried out a survey on the current state of ornamental grasses distributed in the landscaping plants market in South Korea. The grasses were analyzed according to the growing conditions, including habitats, ecological, and horticultural growth characteristics. As a result, 40 genera, 104 species, and 264 taxa of ornamental grasses were verified to be distributed in the market for garden plants in South Korea in August 2021. Poaceae and Cyperaceae are 69.7% and 28.4% among them, respectively. Juncaceae and Typhaceae are of little importance. No Restionaceae is supplied yet. Most of the Poaceae ornamental grasses prefer sunny open land, but others from various habitats are used too. The majority of the Cyperaceae ornamental grasses originate from woodlands, woodland edges, water's edges, and marshes. The market supplies fourteen genera of cool-season and sixteen genera of warm-season grasses. According to life-types of grasses, thirty-eight species are evergreens or semi-evergreens. Thirty-four species are deciduous. Seven species are summer-dormant. According to the growth habits of the grasses, thirty-three species are runners and fifty-one species are clumpers. There are fifteen taxa of ornamental grasses recently selected that have become native grasses.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.6
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• pp.599-609
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• 2021

A novel grounding system, which is presented in IEC 60364, has been adopted since 2021. A safety evaluation for the human body on the grounding system is required due to the various characteristics of the touch voltage and current passing when the human body experiences an electric shock. The Korea Electrical Safety Corporation (KESCO) and Korea Electric Association (KEA) have been conducting a safety technical education on the grounding system. On the other hand, it is difficult to instruct the electrical safety manager because of a lack of safety evaluations for the test equipment on the grounding system. Therefore, this paper modeled and implemented a test device for a safety evaluation depending on the grounding system of IEC 60364. Namely, this paper presents the modeling of the test device for a safety evaluation using PSCAD/EMTDC S/W, which is composed of an AC grid section, s test device section on the grounding system, and a sub-device section. This paper implemented a test device for safety evaluation, which consisted of an AC grid section, TT grounding system section, TN-S grounding system section, and monitoring section. From the simulation and test results with the safety characteristics of the human body in the TT and TN-S grounding system, when the fault impedances are 0[Ω], 10[Ω], and 100[Ω], the currents passing through the human body in the TT grounding system are 104[mA], 87.4[mA], and 35.5[mA], respectively. The corresponding currents in the TN-S grounding system are 54.9[mA], 4.1[mA], and 0.4[mA], respectively. Based on the results, the protection performance for an electric shock to the human body in the TN-S system is better than the TT system. This can be improved when the existing grounding system is changed from the TT system to the TN-S system.

• Journal of Food Hygiene and Safety
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• v.36 no.3
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• pp.220-227
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• 2021

Fluoroimide is a fungicide and is also used as a pesticide for persimmons and potatoes. The established fluoroimide pesticide analysis method takes a long time to perform and uses benzene, a carcinogen. In addition, a lower limit of quantification is required due to enforcement of the Positive List System. Therefore, this study aimed to improve the analysis method for residual fluoroimide to resolve the problems associated with the current method. The analytical method was improved with reference to the increased stability of fluoroimide under acidic conditions. Fluoroimide was extracted under acidic conditions by hydrogen chloride (4 N) and acetic acid. MgSO₄ and NaCl were used with acetonitrile. C₁₈ (octadecylsilane) 500 mg and graphitized carbon black 40 mg were used in the purification process. The experiment was conducted with agricultural products (hulled rice, potato, soybean, mandarin, green pepper), and liquid chromatograph-tandem mass spectrometry was used for the instrumental analysis. Recovery of fluoroimide was 85.7-106.9% with relative standard deviations (RSDs) of less than 15.6%. This study reports an improved method for the analysis of fluoroimide that might contribute to safety by substituting the use of benzene, a harmful solvent. Furthermore, the use of QuEChERS increased the efficiency of the improved method. Finally, this research confirmed the precise limit of quantification and these results could be used to improve the analysis of other residual pesticides in agricultural products.

• Korean Journal of Psychosomatic Medicine
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• v.29 no.1
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• pp.58-66
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• 2021

Objectives : The purpose of this study is to compare the psychosocial characteristics of patients diagnosed with functional gastrointestinal disorder (FGID) by classifying them into irritable bowel syndrome (IBS), functional dyspepsia (FD), functional constipation (FC), functional heartburn (FH) groups, and overlap group (two or more functional diseases) and to examine the factors associated with the quality of life (QoL) of patients with FGID. Methods : A total of 144 patients who were diagnosed with FGID were selected as the subjects. The demographical factors were investigated; Korean-Beck Depression Inventory-II (K-BDI-II), Korean-Beck Anxiety Inventory (K-BAI), Korean version of Childhood Trauma Questionnaire (K-CTQ), Multi-dimensional Scale of Perceived Social Support (MSPSS), Korean Version of Connor-Davidson Resilience Scale (K-CD-RISC), and World Health Organization Quality of Life Assessment Instrument Brief Form (WHOQOL-BREF) were used to evaluate the psychosocial factors. Results : TThe overlap group had a significantly higher K-BDI-II score (F=11.09, p<0.001) and K-BAI score (F=8.93, p<0.001) compared to other groups. In childhood trauma, the IBS patients had a difference in emotional neglect (F=2.54, p=0.04) than the FD patients. The QoL of FGID patients had a negative correlation with depression (r=-0.196, p<0.01), anxiety (r=-0.235, p<0.01), and childhood trauma (r=-0.222, p<0.01), and a positive correlation with social support (r=0.512, p<0.01) and resilience (r=0.581, p<0.01). Conclusions : Overlap group had a higher level of depression and anxiety, and the IBS patient group had a higher level of emotional neglect than the FD patient group in terms of childhood trauma.

• The Journal of Engineering Geology
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• v.30 no.4
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• pp.457-468
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• 2020

Problems arising during pile design works for plant construction, civil and architecture work are mostly come from uncertainty of geotechnical characteristics. In particular, obtaining the N-value measured through the Standard Penetration Test (SPT) is the most important data. However, it is difficult to obtain N-value by drilling investigation throughout the all target area. There are many constraints such as licensing, time, cost, equipment access and residential complaints etc. it is impossible to obtain geotechnical characteristics through drilling investigation within a short bidding period in overseas. The geotechnical characteristics at non-drilling investigation points are usually determined by the engineer's empirical judgment, which can leads to errors in pile design and quantity calculation causing construction delay and cost increase. It would be possible to overcome this problem if N-value could be predicted at the non-drilling investigation points using limited minimum drilling investigation data. This study was conducted to predicted the N-value using an Artificial Neural Network (ANN) which one of the Artificial intelligence (AI) method. An Artificial Neural Network treats a limited amount of geotechnical characteristics as a biological logic process, providing more reliable results for input variables. The purpose of this study is to predict N-value at the non-drilling investigation points through patterns which is studied by multi-layer perceptron and error back-propagation algorithms using the minimum geotechnical data. It has been reviewed the reliability of the values that predicted by AI method compared to the measured values, and we were able to confirm the high reliability as a result. To solving geotechnical uncertainty, we will perform sensitivity analysis of input variables to increase learning effect in next steps and it may need some technical update of program. We hope that our study will be helpful to design works in the future.

• Journal of Korean Society of Forest Science
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• v.110 no.2
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• pp.217-232
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• 2021

This study calculated the productivity and cost of extraction and processing of logging residues by cut-to-length (CTL) and whole-tree (WT) harvesting methods. In addition, the comparative analysis of the characteristics of wood chip fuel to examine whether it was suitable for the fuel conditions of the energy facility. In the harvesting and processing system to produce the wood chips of logging residues the system productivity and cost of the CTL harvesting system were 1.6 Gwt/SMH and 89,865 won/Gwt, respectively. The productivity and cost of the WT harvesting system were 2.9 Gwt/SMH and 72,974 won/Gwt, respectively. The WT harvesting productivity increased 1.3times while harvesting cost decreased by 18.7% compared to the CTL harvesting system. The logging residues of wood chips were not suitable for CTL wood chips based on International Organization for Standardization (ISO 17225-4:2021) and South Korea standard (NIFoS, 2020), but the quality (A2, Second class) was improved through screening operation. The WT-unscreened wood chips conformed to NIFoS standard (second class) and did not conform to ISO but were improved through screening operation (Second class). In addition to the energy facility in plant A, all wood chips except CTL-unscreened wood chips were available through drying processing. The WT-unscreened wood chips were the lowest at 99,408 won/Gwt. Plants B, C, and D had higher moisture content than plant A, so WT-unscreened wood chips without drying processing were the lowest at 57,204 won/Gwt. Therefore, the production of logging residues should improve with operation methods that improve the quality of wood chips required for applying the variable biomass and energy facility.