• Korean Journal of Remote Sensing
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• v.37 no.5_1
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• pp.903-916
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• 2021

An area's topography refers to the shape of the earth's surface, described by its elevation, slope, and aspect, among other features. The topographical conditions determine energy flowsthat move water and energy from higher to lower elevations, such as how much solar energy will be received and how much wind or rain will affect it. Another common factor, the topographic wetness index (TWI), is a calculation in digital elevation models of the tendency to accumulate water per slope and unit area, and is one of the most widely referenced hydrologic topographic factors, which helps explain the location of forest vegetation. Analyses of topographical factors can be calculated using a geographic information system (GIS) program based on digital elevation model (DEM) data. Recently, a large number of free open source software (FOSS) GIS programs are available and developed for researchers, industries, and governments. FOSS GIS programs provide opportunitiesfor flexible algorithms customized forspecific user needs. The majority of biodiversity in island areas exists at about 20% higher elevations than in land ecosystems, playing an important role in ecological processes and therefore of high ecological value. However, island areas are vulnerable to disturbances and damage, such as through climate change, environmental pollution, development, and human intervention, and lacks systematic investigation due to geographical limitations (e.g. remoteness; difficulty to access). More than 4,000 of Korea's islands are within a few hours of its coast, and 88% are uninhabited, with 52% of them forested. The forest ecosystems of islands have fewer encounters with human interaction than on land, and therefore most of the topographical conditions are formed naturally and affected more directly by weather conditions or the environment. Therefore, the analysis of forest topography in island areas can be done more precisely than on its land counterparts, and therefore has become a major focus of attention in Korea. This study is focused on calculating the performance of different topographical factors using FOSS GIS programs. The test area is the island forests in Korea's south and the DEM of the target area was processed with GRASS GIS and SAGA GIS. The final slopes and TWI maps were produced as comparisons of the differences between topographic factor calculations of each respective FOSS GIS program. Finally, the merits of each FOSS GIS program used to calculate the topographic factors is discussed.

• Journal of Bio-Environment Control
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• v.30 no.4
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• pp.419-428
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• 2021

In order to develope a mobile-based greenhouse energy calculation program, firstly, the overall thermal transmittance of 10 types of major covers and 16 types of insulation materials were measured. In addition, to estimate the overall thermal transmittance when the cover and insulation materials were installed in double or triple layers, 24 combinations of double installations and 59 combinations of triple installations were measured using the hotbox. Also, the overall thermal transmittance value for a single material and the thermal resistance value were used to calculate the overall thermal transmittance value at the time of multi-layer installation of covering and insulating materials, and the linear regression equation was derived to correct the error with the measured values. As a result of developing the model for estimating thermal transmittance when installing multiple layers of coverings and insulating materials based on the value of overall thermal transmittance of a single-material, the model evaluation index was 0.90 (good when it is 0.5 or more), indicating that the estimated value was very close to the actual value. In addition, as a result of the on-site test, it was evaluated that the estimated heat saving rate was smaller than the actual value with a relative error of 2%. Based on these results, a mobile-based greenhouse energy calculation program was developed that was implemented as an HTML5 standard web-based mobile web application and was designed to work with various mobile device and PC browsers with N-Screen support. It had functions to provides the overall thermal transmittance(heating load coefficient) for each combination of greenhouse coverings and thermal insulation materials and to evaluate the energy consumption during a specific period of the target greenhouse. It was estimated that an energy-saving greenhouse design would be possible with the optimal selection of coverings and insulation materials according to the region and shape of the greenhouse.

• Journal of Intelligence and Information Systems
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• v.27 no.3
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• pp.29-56
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• 2021

Recently, various types of products have been launched with the rapid growth of the e-commerce market. As a result, many users face information overload problems, which is time-consuming in the purchasing decision-making process. Therefore, the importance of a personalized recommendation service that can provide customized products and services to users is emerging. For example, global companies such as Netflix, Amazon, and Google have introduced personalized recommendation services to support users' purchasing decisions. Accordingly, the user's information search cost can reduce which can positively affect the company's sales increase. The existing personalized recommendation service research applied Collaborative Filtering (CF) technique predicts user preference mainly use quantified information. However, the recommendation performance may have decreased if only use quantitative information. To improve the problems of such existing studies, many studies using reviews to enhance recommendation performance. However, reviews contain factors that hinder purchasing decisions, such as advertising content, false comments, meaningless or irrelevant content. When providing recommendation service uses a review that includes these factors can lead to decrease recommendation performance. Therefore, we proposed a novel recommendation methodology through CNN-based review usefulness score prediction to improve these problems. The results show that the proposed methodology has better prediction performance than the recommendation method considering all existing preference ratings. In addition, the results suggest that can enhance the performance of traditional CF when the information on review usefulness reflects in the personalized recommendation service.

• Journal of Food Hygiene and Safety
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• v.36 no.5
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• pp.430-439
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• 2021

Essential oils with excellent antibacterial activity were used to study the inhibitory effect against the six types of food poisoning biofilms formed on the surfaces of polyethylene (PE) and stainless steel (SS) that are widely used for food processing instruments and containers. The antibacterial activity of 20 kinds of essential oils was tested using the disk diffusion method. The result showed the degree of antibacterial activity in the following order: cinnamon> clove> lemongrass> peppermint> pine needle (highest to lowest). The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of cinnamon and clove oil were in the range of 0.63-1.25 mg/mL and 1.25-2.50 mg/mL, respectively. The MIC and MBC of lemongrass oil were 1.25-2.50 mg/mL and 2.50-5.00 mg/mL, respectively, showing slightly less antibacterial activity. Although the preventive effect of three types of essential oils on the biofilm formation differed slightly depending on food poisoning bacteria, PE, and SS, it was found that the precoating of 0.5% cinnamon, clove, and lemongrass oil on the PE and SS affects the formation of biofilm. Increased essential oil concentration significantly inhibited the biofilm formation for all food poisoning bacteria (P<0.05), and biofilms of Listeria monocytogenes and Staphylococcus aureus were not formed when treated with 0.5% cinnamon and clove oil. The elimination effect of food poisoning bacteria biofilms formed on the surfaces of PE and SS differed depending on the type of food poisoning bacteria. Still, the biofilm elimination effect increased as the essential oil concentration increased, and the biofilm elimination rate of clove oil was generally high. Therefore, this study found that the cinnamon and clove essential oils (0.5%) are suitable natural materials that effectively prevent, inhibit, and remove the biofilms formed by the food poisoning bacteria on the surfaces of polyethylene and stainless steel.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.5
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• pp.75-89
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• 2021

Currently, small business owners are facing a situation where it is difficult to run their business in the existing way due to the spread of digital technology and the prolonged COVID-19. As a necessary competency for them, this study focused on digital literacy and examined the relationship between digital literacy and individual and market characteristics, business performance of small business owners. The specific research purpose is to examine the effect of entrepreneurial characteristics, which are individual factors, and market characteristics, which are environmental factors, on business performance and the mediating effect of digital literacy. In previous studies, various factors explaining the business performance of small business owners were reviewed, and innovation and self-determination, which are entrepreneurial characteristics of small business owners, and market competition and growth were derived as independent variables, and financial and non-financial performance were set as dependent variables. The hypothesis was established as digital literacy was expected to play a role in mediating the relationship between independent and dependent variables. For empirical research, a survey was conducted on small business owners across the country, and the analysis results are summarized as follows. It was found that the innovation and self-determination of small business owners had a positive (+) significant effect on financial and non-financial performance. In addition, it was confirmed that the degree of competition in the market had no significant effect on financial and non-financial performance, and that the growth of the market had a significant positive (+) effect on financial and non-financial performance. In the case of the mediating effect of digital literacy, it was confirmed that innovation had a partial mediating effect on non-financial performance, and digital literacy had a complete mediating effect on the effect of market competition on financial and non-financial performance. Finally, it was confirmed that digital literacy has a partial mediating effect on the effect of market growth on non-financial performance. Looking at the results, it can be seen that the entrepreneurial characteristics of small business owners, which correspond to innovation and self-determination, directly act as a factor to increase business performance, and market characteristics indirectly increase digital literacy to achieve results. Based on the above research results, the implications and limitations of the study and future research directions were presented together.

• Korean Journal of Environment and Ecology
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• v.35 no.5
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• pp.525-547
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• 2021

The main purpose of this study is to examine the use of plant species in ecological restoration projects. To this end, planting drawings from 58 sites that had completed the return of the ecosystem conservation cooperation fund for the past six years were collected and analyzed. The analysis used the construction completion and design drawings to determine the overall selection status and analyze frequency by classifying planted plants into wild and cultivated plants by nature, size, vegetation climate, and upland and wetland habitat. The investigation and analysis process found many cases of wrong plant names, so an analysis was also performed on the matter. In the 58 investigation sites, 282 plants were used for planting: 91 tree species, 69 shrub species, 11 vine species, and 111 herbal species. The most commonly used plant species was Spiraea prunifolia f. simpliciflora, followed by Sorbus alnifolia, Quercus acutissima, Zoysia japonica, Callicarpa dichotoma, and Weigela subsessilisin that order. The most commonly used tree species was Sorbus alnifolia,followed by Quercus acutissima, Zelkova serrata, Chionanthus retusus, and Cornus officinalis, in that order. The most commonly used shrub species was Spiraea prunifolia f. simpliciflora, followed by Weigela subsessilis, Callicarpa dichotoma, Rhododendron yedoense f. poukhanense. and Euonymus alatusin that order. The most commonly used herbal plant species was Zoysia japonica, followed by Dendranthema zawadskii var. latilobum, Aster koraiensis, Miscanthus sacchariflorus, and Pennisetum alopecuroidesin that order. In the analysis by vegetation climate, Spiraea prunifolia f. simpliciflora, Callicarpa dichotoma, and Sorbus alnifoliawere most used in that order in both the temperate central and the warm temperate forest zones, but the pattern does not properly reflect the climate characteristics. In the analysis by habitat, Miscanthus sacchariflorus and Lythrum salicariawere most used in the wetland. In particular, the ratio of wild plants to cultivated plants was 76% to 24%, indicating the ratio of selecting cultivated plants was high. The names of plants on the drawings were mostly common names that did not appear in the Korea National Arboretum or the National Species List of Korea. It is necessary to use proper plant names in the future. Regarding the use of planting plants for ecological restoration, it is necessary to adopt the approach of diversifying selected plants, selecting plants according to characteristics of climate zones, and lowering the specifications of plants used for ecological restoration. Moreover, it is important to fully understand the ecological characteristics of wetland plants and minimize the ratio of using cultivated plants to ensure the plant selection centered on wild plants.

• Korean Journal of Food Science and Technology
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• v.53 no.5
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• pp.640-647
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• 2021

In this study, we analyzed three rice pre-treatment methods for the preparation of mit-sool (first mashing), with godubap (steamed rice), beombeok (undercooked porridge), and juk (porridge). The results can provide basic data for the development of takju with improved quality. In terms of the base alcohol, godubap produced the highest amount of alcohol (8.1%) after two days, followed by beombeok and juk. After two days of fermentation, soluble solids were measured at 15.3, 15.1, and 1.4°Brix in beombeok, juk, and godubap, respectively, The glucose content of godubap did not change significantly; however, the maltose content increased. In beombeok, maltose decreased from 16.48 mg/mL on the initial day 0 to 1.27 mg/mL on day 9. In juk, glucose and maltose increased from 14.05 and 11.49 mg/mL on day 0 to 31.39 and 42.53 mg/mL on day 2, respectively. Succinic acid levels increased in the godubap and beombeok mit-sool. However, succinic acid was not detected in godubap and juk during the initial stage of fermentation, and lactic acid was not detected in beombeok mit-sool. During the fermentation stage of deot-sool (second mashing), the highest alcohol content of takju made with godubap alcohol was 18.0% and the lowest alcohol content was 15.1% in beombeok on day 9. The total acidity was as high as 0.54% for beombeok, 0.41% for juk, and 0.39% for godubap. In the flavor analysis, ethyl caprate and ethyl caprylate, which were high on day 0 in godubap, decreased upon the completion of fermentation on day 9. Banana-flavored isoamyl alcohol content increased. For juk, ethyl caprate and ethyl caprylate, which were high on day 0, decreased on day 9. Flavor components, such as ethyl palmitate and ethyl linoleate were increased.

• Korean Journal of Community Nutrition
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• v.26 no.5
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• pp.327-336
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• 2021

Objectives: This study was conducted to create a 3D printable snack dish model for the elderly with low food or fluid intake along with barriers towards eating. Methods: The decision was made by the hybrid-brainstorming method for creating the 3D model. Experts were assigned based on their professional areas such as clinical nutrition, food hygiene and chemical safety for the creation process. After serial feedback processes, the grape shape was suggested as the final model. After various concept sketching and making clay models, 3D-printing technology was applied to produce a prototype. Results: 3D design modeling process was conducted by SolidWorks program. After considering Dietary reference intakes for Koreans (KDRIs) and other survey data, appropriate supplementary water serving volume was decided as 285 mL which meets 30% of Adequate intake. To consider printing output conditions, this model has six grapes in one bunch with a safety lid. The FDM printer and PLA filaments were used for food hygiene and safety. To stimulate cognitive functions and interests of eating, numbers one to six was engraved on the lid of the final 3D model. Conclusions: The newly-developed 3D model was designed to increase intakes of nutrients and water in the elderly with dementia during snack time. Since dementia patients often forget to eat, engraving numbers on the grapes was conducted to stimulate cognitive function related to the swallowing and chewing process. We suggest that investigations on the types of foods or fluids are needed in the developed 3D model snack dish for future studies.

• Journal of Korea Water Resources Association
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• v.54 no.10
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• pp.795-805
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• 2021

In this study, after developing an LSTM-based deep learning model for estimating daily runoff in the Soyang River Dam basin, the accuracy of the model for various combinations of model structure and input data was investigated. A model was built based on the database consisting of average daily precipitation, average daily temperature, average daily wind speed (input up to here), and daily average flow rate (output) during the first 12 years (1997.1.1-2008.12.31). The Nash-Sutcliffe Model Efficiency Coefficient (NSE) and RMSE were examined for validation using the flow discharge data of the later 12 years (2009.1.1-2020.12.31). The combination that showed the highest accuracy was the case in which all possible input data (12 years of daily precipitation, weather temperature, wind speed) were used on the LSTM model structure with 64 hidden units. The NSE and RMSE of the verification period were 0.862 and 76.8 m³/s, respectively. When the number of hidden units of LSTM exceeds 500, the performance degradation of the model due to overfitting begins to appear, and when the number of hidden units exceeds 1000, the overfitting problem becomes prominent. A model with very high performance (NSE=0.8~0.84) could be obtained when only 12 years of daily precipitation was used for model training. A model with reasonably high performance (NSE=0.63-0.85) when only one year of input data was used for model training. In particular, an accurate model (NSE=0.85) could be obtained if the one year of training data contains a wide magnitude of flow events such as extreme flow and droughts as well as normal events. If the training data includes both the normal and extreme flow rates, input data that is longer than 5 years did not significantly improve the model performance.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.5
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• pp.31-47
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• 2021

The purpose of this study is to demonstrate the moderating effect of technology development activities in the relationship between independent variables such as entrepreneurial orientation and technology innovation capabilities and dependent variables. As a result of analyzing the causal relationship between research variables, it was found that the higher the innovation and initiative among the sub-factors of entrepreneurial orientation, the more positive the technical commercialization performance and product completion. Among the sub-factors of entrepreneurial orientation, risk-taking was found to have a significant effect only on product completion. It was found that the higher the technology commercialization capability and technology convergence capability, the higher the technology commercialization performance, the technology commercialization performance. As a result of analyzing the moderating effect of technology development activities, it was found that technology development management ability, a sub-factor of technology development activities, controls the influence relationship between innovation and risk sensitivity and technology performance. In addition, it was found that the involvement in technology development planning controls the influence relationship between technology convergence capability and technology performance among sub-factors of technology innovation capability. Based on the above analysis results, this study made three suggestions as follows. First, the achievements of technology commercialization to achieve the superiority of corporate competition depend on progressive innovation and risk-taking based on entrepreneurial orientation. It is necessary to find a way to build entrepreneurial orientation from within the organization. Second, due to the nature of the ICT industry, which has a fast pace of technological development and changes in market acceptance, technology commercialization performance will be positive when the capabilities, technology, knowledge, and resources that can quickly lead to product production can be organically linked. Finally, corporate CEOs need to further promote innovation and risk-taking through phased and continuous research activities for technology development. In addition, it is necessary to establish a corporate culture that tolerates various strategies and failures so that understanding of technology convergence can lead to technological performance.