• Journal of Life Science
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• v.32 no.12
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• pp.919-928
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• 2022

As seen in the COVID-19 pandemic, unexpected emergence of new viruses presents serious concern on public health. Especially, the absence of effective vaccines or antiviral drugs against emerging viruses significantly increases the severity of disease and duration of viral circulation among population. Natural products have served as a major source for safe and effective antiviral drugs. In this study, we examined the virucidal activity of medical herb extracts with a view to discover novel antiviral agents with desired levels of safety and antiviral efficacy. Ethanol extracts of ten selected medical herbs were tested for antioxidant activity and in-vitro cytotoxicity in various animal cell lines. Of note, the herbal extracts showed broad and potent virucidal activities against rotavirus, hepatitis A virus, and influenza A virus. The extracts of Sorbus commixta and Glycyrrhiza uralensis showed strong virucidal activities against influenza A virus. We also examined whether the extracts of Sorbus commixta and Glycyrrhiza uralensis can be used as inactivating agents to prepare an inactivated viral vaccine. In a mouse model, influenza A virus inactivated by the extracts elicited high levels of neutralizing antibodies, and the vaccination provided complete protection against lethal challenge. These results suggest that herb-derived natural products can be developed to antiviral drugs as well as inactivating agents for preparation of inactivated viral vaccines.

• Journal of the Korean earth science society
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• v.45 no.3
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• pp.260-276
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• 2024

The purpose of this study is to explore whether pre-service teachers majoring in earth science improve their perception of computational thinking through STEAM classes focused on engineering-based wave power plants. The STEAM class involved designing the most efficient wave power plant model. The survey on computational thinking practices, developed from previous research, was administered to 15 Earth science pre-service teachers to gauge their understanding of computational thinking. Each group developed an efficient wave power plant model based on the scientific principal of turbine operation using waves. The activities included problem recognition (problem solving), coding (coding and programming), creating a wave power plant model using a 3D printer (design and create model), and evaluating the output to correct errors (debugging). The pre-service teachers showed a high level of recognition of computational thinking practices, particularly in "logical thinking," with the top five practices out of 14 averaging five points each. However, participants lacked a clear understanding of certain computational thinking practices such as abstraction, problem decomposition, and using bid data, with their comprehension of these decreasing after the STEAM lesson. Although there was a significant reduction in the misconception that computational thinking is "playing online games" (from 4.06 to 0.86), some participants still equated it with "thinking like a computer" and "using a computer to do calculations". The study found slight improvements in "problem solving" (3.73 to 4.33), "pattern recognition" (3.53 to 3.66), and "best tool selection" (4.26 to 4.66). To enhance computational thinking skills, a practice-oriented curriculum should be offered. Additional STEAM classes on diverse topics could lead to a significant improvement in computational thinking practices. Therefore, establishing an educational curriculum for multisituational learning is essential.

• Progress in Medical Physics
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• v.25 no.2
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• pp.100-109
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• 2014

In stereotactic body radiotherapy (SBRT), the accurate location of treatment sites should be guaranteed from the respiratory motions of patients. Lots of studies on this topic have been conducted. In this letter, a new verification method simulating the real respiratory motion of heterogenous treatment regions was proposed to investigate the accuracy of lung SBRT for Volumetric Modulated Arc Therapy. Based on the CT images of lung cancer patients, lung phantoms were fabricated to equip in $QUASAR^{TM}$ respiratory moving phantom using 3D printer. The phantom was bisected in order to measure 2D dose distributions by the insertion of EBT3 film. To ensure the dose calculation accuracy in heterogeneous condition, The homogeneous plastic phantom were also utilized. Two dose algorithms; Analytical Anisotropic Algorithm (AAA) and AcurosXB (AXB) were applied in plan dose calculation processes. In order to evaluate the accuracy of treatments under respiratory motion, we analyzed the gamma index between the plan dose and film dose measured under various moving conditions; static and moving target with or without gating. The CT number of GTV region was 78 HU for real patient and 92 HU for the homemade lung phantom. The gamma pass rates with 3%/3 mm criteria between the plan dose calculated by AAA algorithm and the film doses measured in heterogeneous lung phantom under gated and no gated beam delivery with respiratory motion were 88% and 78%. In static case, 95% of gamma pass rate was presented. In the all cases of homogeneous phantom, the gamma pass rates were more than 99%. Applied AcurosXB algorithm, for heterogeneous phantom, more than 98% and for homogeneous phantom, more than 99% of gamma pass rates were achieved. Since the respiratory amplitude was relatively small and the breath pattern had the longer exhale phase than inhale, the gamma pass rates in 3%/3 mm criteria didn't make any significant difference for various motion conditions. In this study, the new phantom model of 4D dose distribution verification using patient-specific lung phantoms moving in real breathing patterns was successfully implemented. It was also evaluated that the model provides the capability to verify dose distributions delivered in the more realistic condition and also the accuracy of dose calculation.

• Journal of Internet Computing and Services
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• v.21 no.4
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• pp.17-23
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• 2020

Biometric information indicating measurement items related to human characteristics has attracted great attention as security technology with high reliability since there is no fear of theft or loss. Among these biometric information, fingerprints are mainly used in fields such as identity verification and identification. If there is a problem such as a wound, wrinkle, or moisture that is difficult to authenticate to the fingerprint image when identifying the identity, the fingerprint expert can identify the problem with the fingerprint directly through the preprocessing step, and apply the image processing algorithm appropriate to the problem. Solve the problem. In this case, by implementing artificial intelligence software that distinguishes fingerprint images with cuts and wrinkles on the fingerprint, it is easy to check whether there are cuts or wrinkles, and by selecting an appropriate algorithm, the fingerprint image can be easily improved. In this study, we developed a total of 17,080 fingerprint databases by acquiring all finger prints of 1,010 students from the Royal University of Cambodia, 600 Sokoto open data sets, and 98 Korean students. In order to determine if there are any injuries or wrinkles in the built database, criteria were established, and the data were validated by experts. The training and test datasets consisted of Cambodian data and Sokoto data, and the ratio was set to 8: 2. The data of 98 Korean students were set up as a validation data set. Using the constructed data set, five CNN-based architectures such as Classic CNN, AlexNet, VGG-16, Resnet50, and Yolo v3 were implemented. A study was conducted to find the model that performed best on the readings. Among the five architectures, ResNet50 showed the best performance with 81.51%.

• Horticultural Science & Technology
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• v.33 no.6
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• pp.911-922
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• 2015

This study was carried out to evaluate growth characteristics of Kimchi cabbage cultivated in various highland areas, and to create a predicting model for the production of highland Kimchi cabbage based on the growth parameters and climatic elements. Regression model for the estimation of head weight was designed with non-destructive measured growth variables (NDGV) such as leaf length (LL), leaf width (LW), head height (HH), head width (HW), and growing degree days (GDD), which was $y=6897.5-3.57{\times}GDD-136{\times}LW+116{\times}PH+155{\times}HH-423{\times}HW+0.28{\times}HH{\times}HW{\times}HW$, ($r^2=0.989$), and was improved by using compensation terms such as the ratio (LW estimated with GDD/measured LW ), leaf growth rate by soil moisture, and relative growth rate of leaf during drought period. In addition, we proposed Excel spreadsheet model for simulation of yield prediction of highland Kimchi cabbage. This Excel spreadsheet was composed four different sheets; growth data sheet measured at famer's field, daily average temperature data sheet for calculating GDD, soil moisture content data sheet for evaluating the soil water effect on leaf growth, and equation sheet for simulating the estimation of production. This Excel spreadsheet model can be practically used for predicting the production of highland Kimchi cabbage, which was calculated by (acreage of cultivation) ${\times}$ (number of plants) ${\times}$ (head weight estimated with growth variables and GDD) ${\times}$ (compensation terms derived relationship of GDD and growth by soil moisture) ${\times}$ (marketable head rate).

• Journal of Korea Port Economic Association
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• v.24 no.4
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• pp.363-384
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• 2008

This study aims at improving Korea's competitiveness in port logistics through marketing strategy with integrating the conceptual approach into the empirical one and combining both the oldest military treatise and the newest evaluating model in social science that was applied by the HFP(hierarchical fuzzy process) model enhanced by the KJ method. The empirical results of this study show Busan in the middle among subject ports. At present, Korea plays a reciprocal role in the port market in East Asia, but in the medium- and long-term, Korea's ports will vie together with most major ports in the East Asian region. A descriptive investigation shows that Korea's developing tasks in port logistics must be considered in the context of the direction for developing port policies, the necessity of expanding port facilities in the capital region, securing the sufficient traffic volume through the establishment of the hinterland linking system and its positive utilization, and reforming the direction for developing the global logistics through increased port competitiveness. In the short- and medium-term, Korea must use the opportunity factor of 'Growth and open door policy of China' as a geoeconomic advantage and to utilize Korea's ports as a gate to Chinese foreign trade. With the rise of China's economy, China also plays a significant role in both port and airport markets. Hence, the linking system between the two must be established to meet the expanding traffic volume, especially in the capital area. Moreover, it is necessary for Korea to secure port logistics through the establishment of the hinterland linking system and its positive utilization. The great accomplishment of this paper is to present strategies to increase Korea's port competitiveness in the rapidly changing environments of world logistics with the focus on both the oldest military strategic treatise and the newest empirical method in social science. In order to reinforce this study, it needs further compensative research because the evaluation structure could be subdivided with more extensive and precise criteria.

• The Journal of Society for e-Business Studies
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• v.16 no.3
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• pp.23-45
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• 2011

People could possess different self-identity under virtual world from physical world because of anonymity of the virtual world and this difference could influence their behavior in the virtual world. Based on self-discrepancy theory, this research proposes that continuous use model in self-expression goal. We defined the difference bet ween actual self~identity and ideal self~identity in the virtual world as "self-discrepancy in virtual world", and the difference between actual self-identity in the physical world and actual self-identity in the virtual world as "cross-world self-discrepancy". Before testing hypothesis, we compare the actual self-identity in the online community with the actual self-identity in the physical world, and with ideal self-identity in the virtual world. We derived an index for two different types of self-identity in terms of Personal Self-identity and Social Self-identity through factor analysis. Our results show that online community members have a higher level of ideal self-identity than actual self-identity in online community, and they have better personal self-identity in online community than physical world while a lower level of social self-identity in online community than physical world. The results of the hypothesis testing analysis based on 300 respondents showed that "self-discrepancy in virtual world" negatively influenced perceived usefulness for self-expression while "cross-world self-discrepancy" positively influenced perceived usefulness for self-expression. The perceived usefulness for self-expression and ease of use positively influence both continuous use and knowledge contribution. Specially, the effect of perceived usefulness for self-expression on knowledge contribution is much bigger than the effect of ease of use. This study extends self-discrepancy theory to virtual worlds by suggesting various types of self-discrepancy and by applying the effect of self-discrepancies in online community. Also, this study extends technology acceptance model in the personal goal in terms of self-expression. This study hopes to offer practical insights by suggesting positive effect of self-discrepancy on behavior in the online community.

• Korean Journal of Social Welfare
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• v.54
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• pp.65-97
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• 2003

This study seeks the countermeasures for the successful organization of the social welfare labor union after examining social welfare workers' cognizance about a labor union and analyzing the major factors affecting their participation in a labor union. An analysis of social welfare workers' cognizance about the social welfare labor union. demonstrates that (1) most social welfare workers have positive opinions about a labor union organization and the participation in a labor union, (2) a great part of workers prefer forming a labor union and a professional organization together in relation to the organization of social welfare workers, and (3) the effective strategies for the organization of a labor union are in the order of the uplift of social welfare workers' consciousness, the constitution of the basic organizations which propel the formation of a labor union, and the preparation of policy countermeasures which attain the supports of clients and citizens. An analysis of factors affecting the participation in a labor union shows that the attitude toward the participation behavior (positive results), subjective norm (specific individuals), subjective norm (social constituent members), and perceived behavior control in the analysis model, male, lower position in officers, and lower educational attainment in democratic characteristics, and lower democratic and professional managements in officers and longer working hours in labor environmental conditions affect positively the participation in a labor union. These results suggest several assignments for the successful organization of the social welfare labor union. First the activities that make social welfare workers recognize the beneficial results bringing about by the participation in a labor union need to be carried out, second strategies that persuade the influential individuals to supports the participation in a labor union need to be developed, third activities that make the social constituent members understand the ethical, professional, and non-productive characteristics of social service works not to be confronted with the organization of a labor union should be pursued, fourth the organizational environments in which social welfare workers can freely participate in a labor union according to their intentions need to be made up, fifth the policy countermeasures which attain the support of social welfare workers, clients and citizens should be developed and carried out, and finally the basic organizations that effectively propel the formation of a labor union need to be constituted.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.6
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• pp.785-795
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• 2018

The International Maritime Organization (IMO) has recognized the risk of hull fouling and announced '2011 Guidelines for the control and management of ship's biofouling to minimize the transfer of invasive aquatic species'and is planning international regulations to enforce them in the future. In this study, to effectively respond to future international regulation, we introduce the case of leading countries related to management of hull fouling and also investigate environmental risk assessment techniques for in-water cleaning. Australia and New Zealand, the leading countries in hull fouling management, have established hull fouling regulations through biological and chemical risk assessment based on in-water cleaning scenarios. Most European countries without their government regulation have been found to perform in-water cleaning in accordance with the IMO's hull fouling regulations. In the Republic of Korea, there is no domestic law for hull fouling organisms, and only approximately 17 species of marine ecological disturbance organisms, are designated and managed under the Marine Ecosystem Law. Since in-water cleaning is accompanied by diffusion of alien species and release of chemical substances into aquatic environments, results from biological as well as chemical risk assessment are performed separately, and then evaluation of in-water cleaning permission is judged by combining these two results. Biological risk assessment created 40 codes of in-water cleaning scenarios, and calculated Risk Priority Number (RPN) scores based on key factors that affect intrusion of alien species during in-water cleaning. Chemical risk assessment was performed using the MAMPEC (Marine Antifoulant Model to Predict Environmental Concentrations), to determine PEC and PNEC values based on copper concentration released during in-water cleaning. Finally, if the PEC/PNEC ratio is >1, it means that chemical risk is high. Based on the assumption that the R/V EARDO ship performs in-water cleaning at Busan's Gamcheon Port, biological risk was estimated to be low due to the RPN value was <10,000, but the PEC/PNEC ratio was higher than 1, it was evaluated as impossible for in-water cleaning. Therefore, it will be necessary for the Republic of Korea to develop the in-water cleaning technology by referring to the case of leading countries and to establish domestic law of ship's hull fouling management, suitable for domestic harbors.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.3
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• pp.33-46
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• 2020

This study analyzes the entrepreneurship education phenomena for agri-food entrepreneurs whose main business is the production of agricultural products and the sale of processed products, using the qualitative study Strauss & Corbin(1998)'s evidence theory approach. From the entrepreneur's point of view, I would like to summarize the phenomena that appear in education, and to prepare a theoretical basis for explaining the phenomena. The importance of entrepreneurship education is emphasized to cultivate the ability to develop and provide products tailored to customers. The necessity of education leads to an increase in demand according to the situational awareness of the founders, and the quantitative increase in entrepreneurship education in the agri-food sector is a clear trend. Inevitably, the need for various discussions on systematic and effective entrepreneurship education is raised. For the study, an interview was conducted with preliminary or entrepreneur who have experienced entrepreneurship education in the agri-food sector. As a research method, I use Strauss & Corbin(1998)'s approach and analyze qualitative data using QSR's NVIVO 12 program. Through this study, it was found that contextual and systematic entrepreneurship education in the agri-food sector has the effect of strengthening competitiveness and strengthening sales. There is a need for follow-up management of trainees. Strengthening the competitiveness of start-ups is based on training professional manpower through education and linking regions with cities. Strengthening sales is based on product planning and market development. This study explores entrepreneurship education in the agri-food sector, which has not been actively conducted in the past. Exploratory analysis on the experiences of the founders of agri-food sector as education demanders has an important meaning for understanding the phenomenon of start-up education.