• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.2
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• pp.67-71
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• 2023

Recently, there are increasing cases of managing software labs by assigning virtual PCs in the cloud instead of physical PCs to each student. In this paper, we design and implement a Linux-based software practice platform that allows students to efficiently build their environments in the cloud. In our platform, instructors can create and control virtual machine templates for all students at once, and students practice on their own machines as administrators. Instructors can also troubleshoot each machine and restore its state. Meanwhile, the biggest obstacle to implementing this approach is the difficulty of predicting the costs of cloud services instantly. To cope with this situation, we propose a model that can estimate the cost of cloud resources used. By using daemons in each user's virtual machine, we instantly estimate resource usage and costs. Although our model has very low overhead, the predicted results are very close to the actual resource usage measured by cloud service providers. To further validate our model, we used the proposed platform in a Linux practice lecture for a semester and confirmed that the proposed model is very accurate.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.34 no.3
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• pp.205-225
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• 2023

The Study is to investigate information resources recognition of collection development policy that is a key element of Gwangju representative library. 68 Librarians, 98 library users and 20 libraries responded the questions of information resources. The fields of the questions are media, subjects and levels of information resources. The results of the research are as follows. First, the correlation coefficients between librarian group's preference and need is lower than that of the user group. Second, information resources for the knowledge-disadvantaged has low preference and need but the actual usage rate was high. Third, Librarians need to transfer historical paper and books, historical objects, technical reports and journal articles to the representative library. Fourth, information resources about philosophy have middle preference, low need and the resources have low need for transfer to representative library. Fifth, local historical resources and administrative policy resources has low usage rate high need for transfer to representative library. Sixth, the level of public library in Gwangju is 1.837 and the expectative level of Gwangju representative library is 3.325.

• Korean Journal of Community Nutrition
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• v.28 no.4
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• pp.269-281
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• 2023

Objectives: This study aimed to examine the frequency of convenience food consumption at convenience stores (CVS) and the CVS usage patterns of middle and high school students as well as to understand students' attitude toward sodium and sugar reduction. Methods: We used an online questionnaire for data collection. The questionnaire comprised five distinct categories: general characteristics, CVS usage, frequency of consumption according to convenience food menus at CVS, attitude toward sodium and sugar reduction, and adherence to dietary guidelines. Results: A total of 75 students from Seoul (14 middle school students and 61 high school students) participated in the study. Most respondents visit CVS 3-5 times a week. CVS are predominantly used during weekdays, mostly during lunch, and dinner. The students mostly checked the caloric content and expiration date as food labeling information. The participants were aware of the need to reduce their sugar and sodium intake. Among frequent CVS convenience food consumers, there was an increased consideration of the need to reduce their sugar and sodium consumption, despite their actual selection of foods with high sugar and sodium content. Additionally, they did not check the sugar and sodium levels indicated in food labeling. Further, the dietary action guide from the Ministry of Health and Welfare were poorly followed by most students. Conclusions: There is a need for nutrition education specifically addressing the sugar and sodium content of the convenience foods predominantly consumed by students. Additionally, educating students with frequent convenience food consumption to actively check the sugar and sodium information on food labels could help promote healthier food choices.

• Journal of Practical Engineering Education
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• v.15 no.2
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• pp.389-400
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• 2023

Technological advancements in the field of information and communication have led to the advent and usage of various types of smart devices, which have significantly altered people's usage behaviors and environments. This change has also been applied to the learning environment, where various smart devices are appearing and the learning behavior of learners is changing accordingly. In this study, we investigate learners' perceptions of digital note-taking behaviors focusing on the recently emerged learning media, tablet PCs and digital pens. Drawing upon the expectancy-confirmation model, we conduct a study on the factors affecting the (dis)confirmation and (dis)satisfaction of undergraduate students with tablet PCs and digital pens by comparing their expectations with their actual use experiences. An open-ended survey was conducted among students at C University in Korea, and the responses were analyzed through qualitative content analysis to derive four factors of expectation-confirmation and satisfaction and three factors of expectation-disconfirmation and dissatisfaction. Based on these findings, we provide academic and educational implications.

• Journal of Internet Computing and Services
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• v.24 no.5
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• pp.17-27
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• 2023

Today, as AI (Artificial Intelligence) technology develops and its practicality increases, it is widely used in various application fields in real life. At this time, the AI model is basically learned based on various statistical properties of the learning data and then distributed to the system, but unexpected changes in the data in a rapidly changing data situation cause a decrease in the model's performance. In particular, as it becomes important to find drift signals of deployed models in order to respond to new and unknown attacks that are constantly created in the security field, the need for lifecycle management of the entire model is gradually emerging. In general, it can be detected through performance changes in the model's accuracy and error rate (loss), but there are limitations in the usage environment in that an actual label for the model prediction result is required, and the detection of the point where the actual drift occurs is uncertain. there is. This is because the model's error rate is greatly influenced by various external environmental factors, model selection and parameter settings, and new input data, so it is necessary to precisely determine when actual drift in the data occurs based only on the corresponding value. There are limits to this. Therefore, this paper proposes a method to detect when actual drift occurs through an Anomaly analysis technique based on XAI (eXplainable Artificial Intelligence). As a result of testing a classification model that detects DGA (Domain Generation Algorithm), anomaly scores were extracted through the SHAP(Shapley Additive exPlanations) Value of the data after distribution, and as a result, it was confirmed that efficient drift point detection was possible.

• Science of Emotion and Sensibility
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• v.13 no.3
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• pp.493-500
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• 2010

The development of new technology and diversity in user needs lead mobile phone manufacturers to establish new strategies different from the existing for user attraction. Product identity, and brand image are major strategies for differentiation and adding new values to a product. This research starts with stating emotional brand image as the brand image made by the actual usage and the emotion built from the experience while using the product. This research will compare emotional brand image of the three major mobile phone manufactures in Korea (Brand A, C, and S) using evaluation of six representative emotions from users while using the product. The result of evaluating actual mobile phone users and the emotion built while actually using the product showed the brand image, and especially the emotional side of Korean mobile phone manufacturers. The result of this research itself would not be sufficient to simply state the emotional brand image of Korean mobile phone manufactures, but with further research including age, profession, gender and other demographic factors the result of this research would surely be able to abstract a clearer view of emotional brand image of Korean mobile phone manufactures.

• Journal of the Korean Society of Clothing and Textiles
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• v.39 no.6
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• pp.924-937
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• 2015

This study surveyed the recognition and credibility of infant's organic cotton apparel and examined the current quality of children's organic cotton clothes available in the market. This study contributes to improve fabric certification programs and safety standards by understanding customer opinions and actual quality. A customer survey revealed that customers believe that organic cotton products should not include chemicals such as pesticides, fluorescent whitening agents and chemical colors; in addition, customers have high expectations for safety as well as worries about the products' validity. Children's underwear was the most purchased item category among organic cotton products. Current organic cotton certification programs are voluntary with multiple organizations that provide various certification standards. A total of 34.2% of children's organic cotton clothes sold at online and offline stores were not certified, and 10.5% had invalid certification information. This may substantially lower the credibility of organic cotton products and requires immediate change. Examination of organic cotton products showed that products do not meet customer expectations for quality and safety: 3 out of 8 products used accessories (buttons and wappens) that include harmful chemicals such as lead, phthalate and formaldehyde, 6 products used fluorescent whitening agents, and 4 products used other fabrics such as rayon, polyurethane and polyester. GOTS mark is the most recognized organic certification, but it still allows the usage of fluorescent whitening agents, which indicates a gap between customer opinions and actual certification standards. Managing national-level mandatory certification programs like food and setting quality standards that meets customer expectations are required to enhance the credibility of organic cotton products.

• Structural Engineering and Mechanics
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• v.26 no.6
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• pp.709-723
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• 2007

Considering the vast usage of time-history dynamic analyses to calculate structural responses and lack of sufficient and suitable earthquake records, generation of artificial accelerograms is very necessary. The main target of this paper is to present a novel method based on nonstationary Kanai-Tajimi model and wavelet transform to generate more artificial earthquake records, which are compatible with target spectrum. In this regard, the generalized nonstationary Kanai-Tajimi model to include the nonstationary evaluation of amplitude and dominant frequency of ground motion and properties of wavelet transform is used to generate ground acceleration time history. Application of the method for El Centro 1940 earthquake and two Iranian earthquakes (Tabas 1978 and Manjil 1990) is presented. It is shown that the model and identification algorithms are able to accurately capture the nonstationary features of these earthquake accelerograms. The statistical characteristics of the spectral response of the generated accelerograms are compared with those for the actual records to demonstrate the effectiveness of the method. Also, for comparison of the presented method with other methods, the response spectra of the synthetic accelerograms compared with the models of Fan and Ahmadi (1990) and Rofooei et al. (2001) and it is shown that the response spectra of the synthetic accelerograms with the method of this paper are close to those of actual earthquakes.

• Journal of The Korean Association of Information Education
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• v.13 no.3
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• pp.371-382
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• 2009

The most widely-used typical information service of national education, EDUNET has members of 5.8million. But it has been not used in the fields of elementary school. There are short-comings in its usage by members of the elementary school teaching. We would like to find solutions by using a questionnaire to the teachers of elementary school in the Busan and Gyeongsangnam-do, which resolve the problems of the actual condition. Analytical results show that 93.1 percent of the teachers usually use private education information service and 5.3 percent use EDUNET service. The main reason why teachers discourage the use of EDUNET service is that it provides the inconvenience of searching data(29.4%) and insufficiency of good quality contents(25%). In order to revitalize using EDUNET service, EDUNET has to improve on the perceived cumbersome unhandy of searching tools and help teachers to use EDUNET service by offering information of high quality.

• Korean Institute of Interior Design Journal
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• v.22 no.1
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• pp.307-317
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• 2013

Elementary school's physical environment is critical to lower grade students. Among the many physical conditions, Toilet, which belongs to health and sanitation category is very important to those who start school for the first time. The purpose of this study is for suggesting the guidelines of toilet design reflecting psychological and behavioral aspects of lower grade students. The research was executed as follows. Firstly, focused survey groups were carefully chosen. Five elementary schools were selected, being all open after 2005 under Seoul Gangseo District Office of Education. Secondly, field study was executed to find out toilet usage, during the period between April to June 2012, by visiting schools to see basic facilities, taking pictures and making actual measurement in each toilets. The architectural analysis was focused on location, moving line, actual size and space zoning, while the interior analysis being on finishing materials and the design of sanitary equipments. And the design elements such as color, lighting fixture, art works or signage were analysed, too. Finally, questionnaire survey was done to find out preferences of lower grade students. As a result, the guidelines of toilet design can be divided into two main parts, Physical and Psychological. For the Physical part, it is necessary for related facilities to be concentrated in order to give easy access. In addition, good ventilation, better lighting and to install sanitary equipments ergonomically are required. Furthermore, safe and clean maintenance should be considered. Psychologically, the design should be directed for making lower grade students come to toilets with comfort and more pleasantly.