• KIPS Transactions on Computer and Communication Systems
• /
• v.12 no.10
• /
• pp.299-308
• /
• 2023

As the spectrum shortage problem has accelerated by the emergence of various services, New Radio-Unlicensed (NR-U) has appeared, allowing users who communicated in licensed bands to communicate in unlicensed bands. However, NR-U network users reduce the performance of Wi-Fi network users who communicate in the same unlicensed band. In this paper, we aim to simultaneously maximize the fairness and throughput of the unlicensed band, where the NR-U network users and the WiFi network users coexist. First, we propose an optimal power allocation scheme based on Monte Carlo Policy Gradient of reinforcement learning to maximize the sum of rates of NR-U networks utilizing rate-splitting multiple access in unlicensed bands. Then, we propose a channel occupancy time division algorithm based on sequential Raiffa bargaining solution of game theory that can simultaneously maximize system throughput and fairness for the coexistence of NR-U and WiFi networks in the same unlicensed band. Simulation results show that the rate splitting multiple access shows better performance than the conventional multiple access technology by comparing the sum-rate when the result value is finally converged under the same transmission power. In addition, we compare the data transfer amount and fairness of NR-U network users, WiFi network users, and total system, and prove that the channel occupancy time division algorithm based on sequential Raiffa bargaining solution of this paper satisfies throughput and fairness at the same time than other algorithms.

• Journal of the Korean Applied Science and Technology
• /
• v.39 no.6
• /
• pp.748-759
• /
• 2022

The purpose of this study is to investigate the mediating effect of job commitment and the moderating effect of job burnout on the relationship between the protean career orientation and subjective career success of hair designers. For this purpose, a survey was conducted on 163 employees working at a representative A brand hair salon in Korea, and statistical analysis was conducted using SPSS 21, and SPSS Process Macro v. 3.3. The results of this study are as follows: First, Protean career orientation affects job commitment to focus on oneself in all aspects related to their job, and as a result, it has a mediating effect on subjective career success that satisfies their career. Second, Through the interaction between protean career orientation and job burnout, the moderating effect on job commitment was confirmed. The significance of this study is to suggest a career success plan for hair salon workers with relatively high turnover rate in the service field by dealing with the understanding of the hair salon organizational culture and the lack of hair designer protean career orientation in terms of the mediating role of job commitment and job burnout in career success.

• Industry Promotion Research
• /
• v.9 no.2
• /
• pp.13-22
• /
• 2024

The purpose of this study is to derive passenger trends and change rates for each airline and identify directionality and synchronization phenomenon. Data by each airlines was collected from the National Statistics Forum of Statistics Korea, and we used a total of 156 monthly data from January 2011 to December 2023. In this study, the rate of change was calculated for domestic Full Service Carriers (Korean Air, Asiana Airlines) and Low Cost Carriers (Jeju Air, Jin Air, T'way, foreign airlines). As a result of the analysis, the correlation was found to be high for KOREA in that order: Asiana, Korean Air, Jeju Air, T'way, Jin Air, foreign airlines. The rate of increase was highest in that order: T'way, Jin Air, Jeju Air, foreign airlines, Asiana, Korean Air. In the Scatter analysis, Asiana and Korean Air showed a very strong synchronization with KOREA. In addition, Jeju Air, T'way, Jin Air and foreign airlines also showed the same direction toward KOREA to a certain degree. In the Box-Box Plot analysis, it was determined that each airline experienced a number of unusual sudden fluctuations due to the outbreak of COVID-19. Passengers have a wider range of choices due to the emergence of Low Cost Carriers, and as a result, expectations for airline service are increasing. Airlines will need to make appropriate environmental improvements to satisfy these needs for corporate development.

• Smart Media Journal
• /
• v.12 no.11
• /
• pp.27-35
• /
• 2023

Fourth Industrial Revolution and COVID-19 pandemic have boosted the use of Government 24 app for public service complaints in the era of non-face-to-face interactions. there has been a growing influx of complaints and improvement demands from users of public apps. Furthermore, systematic management of public apps is deemed necessary. The aim of this study is to analyze the grievances of Government 24 app users, understand the current dissatisfaction among citizens, and propose potential improvements. Data were collected from the Google Play Store from May 2, 2013, to June 30, 2023, comprising a total of 6,344 records. Among these, 1,199 records with a rating of 1 and at least one 'thumbs-up' were used for topic modeling analysis. The analysis revealed seven topics: 'Issues with certificate issuance,' 'Website functionality and UI problems,' 'User ID-related issues,' 'Update problems,' 'Government employee app management issues,' 'Budget wastage concerns ((It's not worth even a single star) or (It's a waste of taxpayers' money)),' and 'Password-related problems.' Furthermore, the overall trend of these topics showed an increase until 2021, a slight decrease in 2022, but a resurgence in 2023, underscoring the urgency of updates and management. We hope that the results of this study will contribute to the development and management of public apps that satisfy citizens in the future.

• Information Systems Review
• /
• v.25 no.1
• /
• pp.145-164
• /
• 2023

The proliferation of online reviews on dining experiences has significantly affected consumers' choices of restaurants, especially overseas. Food quality, service, ambiance, and price have been identified as specific attributes for the choice of a restaurant in prior studies. In addition to these four representative attributes, cultural factors, which may also significantly impact the choice of a restaurant for tourists, in particular, have not received much attention in previous studies. This study employs the text mining technique to analyze over 10,000 online reviews of 76 Korean restaurants posted by Chinese tourists on dianping.com to explore the influence of cultural factors on the consumer's choice of restaurants in the overseas travel context. The findings reveal that "Hallyu (Korean Wave)" influences Chinese tourists' dining experiences in Korea and their satisfaction. Moreover, Korean food-related words, such as cold noodle, bibimbap, rice cake, pig trotters, and kimchi stew, appeared across all the review topics. Our findings contribute to the existing tourism and hospitality literature by identifying the critical role of cultural factors on consumers', especially tourists', satisfaction with the choice of a restaurant using text mining. The findings also provide practical guidance to restaurant owners in Korea to attract more Chinese tourists.

• Journal of the Korean Society for Library and Information Science
• /
• v.58 no.2
• /
• pp.251-268
• /
• 2024

Recently, with the implementation of the "e-Government Performance Management Guidelines," there is a growing demand for setting performance indicators for information systems. For systems that provide information services to the public, such as CODIL, it is not easy to set performance indicators. This study presented a research model that applies Monte Carlo simulation to set expected performance targets that can be achieved through CODIL based on objective evidence. Among the survey contents conducted from 2015 to 2023, the statistical characteristics of user satisfaction regarding the frequency of use of construction technology information provided by CODIL were designated as input variables. Future expected targets and confidence intervals from 2024 to 2026 were designated as outcome variables. The expected target value was measured by generating 5 simulation alternatives and 1,000 random numbers for each alternative. Next, the measured expected goals were interpreted and compared with the results of time series regression analysis measured in previous studies. Although, as in previous studies, the expected target value could not be predicted based on time series regression analysis that considers the correlation between years. However, compared to previous studies, this study can be considered a more accurate analysis result because it predicted the expected target value based on 5,000 input variables.

• Journal of Digital Convergence
• /
• v.22 no.1
• /
• pp.33-38
• /
• 2024

In recent years, as more and more middle-aged people who worked at companies are retiring, they are becoming interested in starting their own businesses, and the rate of middle-aged people starting businesses is increasing. The purpose of this study was to analyze the quality and satisfaction of educational services and trust in educational institutions in providing entrepreneurship education to prospective entrepreneurs over the age of 40 who want to start a business, and to analyze the impact of entrepreneurship education on entrepreneurship in the future. Afterwards, the goal is to establish an education strategy to improve the quality of entrepreneurship education. To achieve the purpose of the study, a hypothesis was established and an empirical analysis was conducted on educated prospective entrepreneurs and retirees over 40 years of age. As a result of the analysis, it was confirmed that confidence and reliability ultimately influence the factors that increase satisfaction with entrepreneurship education for middle-aged and older people. Satisfaction was found to play a meaningful role in trust. The research points out that entrepreneurship education institutions should provide education centered on the trainees rather than entrepreneurship education centered on support organizations. Moreover, due to the diversity of education, not only the content and method of education but also the education of employees working in supporting organizations is important.

• Information Systems Review
• /
• v.23 no.1
• /
• pp.155-172
• /
• 2021

With the recent increase in online product purchases, a recommender system that recommends products considering users' preferences has still been studied. The recommender system provides personalized product recommendation services to users. Collaborative Filtering (CF) using user ratings on products is one of the most widely used recommendation algorithms. During CF, the item-based method identifies the user's product by using ratings left on the product purchased by the user and obtains the similarity between the purchased product and the unpurchased product. CF takes a lot of time to calculate the similarity between products. In particular, it takes more time when using text-based big data such as review data of Amazon store. This paper suggests a hybrid recommendation system using a 2-phase methodology and text data mining to calculate the similarity between products easily and quickly. To this end, we collected about 980,000 online consumer ratings and review data from the online commerce store, Amazon Kinder Store. As a result of several experiments, it was confirmed that the suggested hybrid recommendation system reflecting the user's rating and review data has resulted in similar recommendation time, but higher accuracy compared to the CF-based benchmark recommender systems. Therefore, the suggested system is expected to increase the user's satisfaction and increase its sales.

• Information Systems Review
• /
• v.18 no.4
• /
• pp.121-140
• /
• 2016

Today, consumers are interested in branded apps as new marketing channels. Consumers do not have ready access to information that will enable them to judge the quality of a particular product or service before purchase, but they will gain such information with branded apps. As they need to be actively chosen and downloaded to users' smartphone by the users themselves, branded apps have greater marketing effectiveness and influence than traditional channels. Therefore, corporations that place emphasis on interactions with customers anticipate a new marketing effect with their branded apps. With previous research on smartphone applications as a background, this research finds key factors in branded apps that influence users' satisfaction. Additionally, the study centers on the relationship in which satisfaction in the branded app significantly influences the purchase intention for the branded product/service.

• Journal of Intelligence and Information Systems
• /
• v.24 no.1
• /
• pp.227-252
• /
• 2018

The evolution of instant communication has mirrored the development of the Internet and messenger applications are among the most representative manifestations of instant communication technologies. In messenger applications, senders use emoticons to supplement the emotions conveyed in the text of their messages. The fact that communication via messenger applications is not face-to-face makes it difficult for senders to communicate their emotions to message recipients. Emoticons have long been used as symbols that indicate the moods of speakers. However, at present, emoticon-use is evolving into a means of conveying the psychological states of consumers who want to express individual characteristics and personality quirks while communicating their emotions to others. The fact that companies like KakaoTalk, Line, Apple, etc. have begun conducting emoticon business and sales of related content are expected to gradually increase testifies to the significance of this phenomenon. Nevertheless, despite the development of emoticons themselves and the growth of the emoticon market, no suitable emoticon recommendation system has yet been developed. Even KakaoTalk, a messenger application that commands more than 90% of domestic market share in South Korea, just grouped in to popularity, most recent, or brief category. This means consumers face the inconvenience of constantly scrolling around to locate the emoticons they want. The creation of an emoticon recommendation system would improve consumer convenience and satisfaction and increase the sales revenue of companies the sell emoticons. To recommend appropriate emoticons, it is necessary to quantify the emotions that the consumer sees and emotions. Such quantification will enable us to analyze the characteristics and emotions felt by consumers who used similar emoticons, which, in turn, will facilitate our emoticon recommendations for consumers. One way to quantify emoticons use is metadata-ization. Metadata-ization is a means of structuring or organizing unstructured and semi-structured data to extract meaning. By structuring unstructured emoticon data through metadata-ization, we can easily classify emoticons based on the emotions consumers want to express. To determine emoticons' precise emotions, we had to consider sub-detail expressions-not only the seven common emotional adjectives but also the metaphorical expressions that appear only in South Korean proved by previous studies related to emotion focusing on the emoticon's characteristics. We therefore collected the sub-detail expressions of emotion based on the "Shape", "Color" and "Adumbration". Moreover, to design a highly accurate recommendation system, we considered both emotion-technical indexes and emoticon-emotional indexes. We then identified 14 features of emoticon-technical indexes and selected 36 emotional adjectives. The 36 emotional adjectives consisted of contrasting adjectives, which we reduced to 18, and we measured the 18 emotional adjectives using 40 emoticon sets randomly selected from the top-ranked emoticons in the KakaoTalk shop. We surveyed 277 consumers in their mid-twenties who had experience purchasing emoticons; we recruited them online and asked them to evaluate five different emoticon sets. After data acquisition, we conducted a factor analysis of emoticon-emotional factors. We extracted four factors that we named "Comic", Softness", "Modernity" and "Transparency". We analyzed both the relationship between indexes and consumer attitude and the relationship between emoticon-technical indexes and emoticon-emotional factors. Through this process, we confirmed that the emoticon-technical indexes did not directly affect consumer attitudes but had a mediating effect on consumer attitudes through emoticon-emotional factors. The results of the analysis revealed the mechanism consumers use to evaluate emoticons; the results also showed that consumers' emoticon-technical indexes affected emoticon-emotional factors and that the emoticon-emotional factors affected consumer satisfaction. We therefore designed the emoticon recommendation system using only four emoticon-emotional factors; we created a recommendation method to calculate the Euclidean distance from each factors' emotion. In an attempt to increase the accuracy of the emoticon recommendation system, we compared the emotional patterns of selected emoticons with the recommended emoticons. The emotional patterns corresponded in principle. We verified the emoticon recommendation system by testing prediction accuracy; the predictions were 81.02% accurate in the first result, 76.64% accurate in the second, and 81.63% accurate in the third. This study developed a methodology that can be used in various fields academically and practically. We expect that the novel emoticon recommendation system we designed will increase emoticon sales for companies who conduct business in this domain and make consumer experiences more convenient. In addition, this study served as an important first step in the development of an intelligent emoticon recommendation system. The emotional factors proposed in this study could be collected in an emotional library that could serve as an emotion index for evaluation when new emoticons are released. Moreover, by combining the accumulated emotional library with company sales data, sales information, and consumer data, companies could develop hybrid recommendation systems that would bolster convenience for consumers and serve as intellectual assets that companies could strategically deploy.