• Fourth Industrial Review
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• v.4 no.2
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• pp.11-18
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• 2024

Purpose: This research delves into the topic by exploring the impacts of the Unified Theory of Acceptance and Use of Technology (UTAUT) on the fourth industrial setting. As the study begins with a comprehensive review of the literature to find other scholars' contributions, the present authors try to synthesize and integrate scattered related topics in the literature dataset. Research design, data and methodology: We used a descriptive, causal, and explanatory research design hybrid. A causal research design is an approach used to investigate the interaction and relationship between given variables. The screening began with searching using keywords, filtering using the inclusion criteria, and arriving at the final set of sources. Results: There were four crucial findings: 1. The Performance Expectancy Construct Has Strongly Influenced and Influenced the Decision to Acquire and Use a Given Technology. 2. Effort Expectancy Construct Has Influenced the Trends of Adopting. 3. Social Influence and Impact on Choice and Use of Technologies. 4. Facilitating Conditions as A Factor in Modern Production and Consumption. Conclusions: All in all, UTAUT is used in a predictive manner and very instrumental for the producers and users of various technologies. Four primary constructs are critical in making the theory complete, essential, and reliable within the fourth industrial setting.

• KSCI Review
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• v.14 no.2
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• pp.185-197
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• 2006

A star schema consists of a central fact table, which is surrounded by one or more dimension tables. Each row int the fact table contains a multi-part primary key(or a composite foreign key) along with one or more columns containing various facts about the data stored in the row Each of the composit foreign key components is related to a dimensional table. The combination of keys in the fact table creates a composite foreign key that is unique to the fact table record. The composite foreign key, however, is rarely unique to the fact table record in real-world applications, particularly in financial applications. In order to make the composite foreign key be the determinant in real-world application, some precalculation might be performed in the SQL relational database, and cached in the OLAP database. However, there are many drawbacks to this approach. In some cases, this approach might give users the wrong results. In this paper, an approach to fact table modeling and related MDX query composing, which can be used in real-world applications without performing any precalculation and gives users the correct results, is proposed.

• Management & Information Systems Review
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• v.28 no.1
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• pp.125-156
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• 2009

The primary purpose of this study is to identify the determinants of the users' satisfaction and commitment in personal media. For these purposes, we developed a research model based on the literature reviews of personal media, perceived risk and interactivity, satisfaction, and commitment. This study has identified four dimensions in the concept of perceived risk, such as privacy risk, social risk, time loss risk, and economic risk, and three dimensions in the concept of perceived interactivity, such as active control, two-way communication, and responsiveness. In survey, data were collected from 428 male and female who have an experience in personal media. Data was analyzed factor analysis, reliability analysis, measurement model analysis, and structural model analysis by utilizing SPSS 15.0 and AMOS 5.0 program. Analysis results of research model indicate the following. Firstly, privacy risk, active control, two-way communication, and responsiveness are significantly related satisfaction. Secondly, privacy risk, time loss risk, economic risk, active control, and two-way communication are significantly related commitment. Thirdly, users' satisfaction has positive relationship with commitment in personal media. Based on these results, theoretical implications for relevant researchers and managerial implications for personal media vitalization and marketing strategy are discussed. Finally, limitations for this study and further research issues are suggested.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.5
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• pp.69-75
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• 2018

Recently, Non-orthogonal multiple access (NOMA) has been focused for the next generation multiple access, which has more spectral efficiency under the limited spectrum bandwidth. Moreover, the spectrum efficiency can be improved by cognitive radio in which the unlicensed secondary users can access the spectrum that is used by the licensed primary user under the limited interference. Hence, we consider the combination of NOMA and cognitive radio, and derive the performance of the cognitive cooperative NOMA system. For the cooperation, a relay is selected among near users, and the selection combining is assumed at a far user. The outage probability of the selected relay and the far user is derived in closed-form, respectively. The provided numerical results are matched well with the Monte Carlo simulation. Numerical results showed that the performance of the relay is affected from the power allocation coefficient, the minimum outage probability is observed at 0.86 of the power allocation coefficient for far user under the given conditions. More than 15 dB of signal-to-noise ratio is required to meet the outage probability of $1{\times}10^{-13}$ for the far user with the frequency acquisition probability of 0.5 compared to that of 1. It shows that the performance of the far user is very sensitive to the acquisition probability of the cognitive relay.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.9
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• pp.18-25
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• 2016

In D2D communications underlaying a multicell network, it is of primary importance to ensure coexistence of cellular links and D2D links with minimal interference. Therefore, resource allocation scheme for D2D links should be designed to limit the interference between cellular links and D2D links. In this paper, we propose an effective resource allocation scheme for multiple D2D links which share the uplink spectrum resource with cellular users in a multicell network. Under the assumption that the locations of users are known to the base station, the proposed scheme allocates cellular resources to D2D links, such that the interference between a cellular link and multiple D2D links is minimized. In particular, we compute two constants from the path loss model and then use the constants to protect both cellular and D2D links. Simulation results are provided to verify the performance of the proposed scheme.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.745-755
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• 2017

University campuses try to satisfy students' demands. Therefore, the physical environment of university campuses keeps changing. Due to the increasing the number of students and shortage of school building facilities, it is necessary to improve the facilities and create new space in the campus, in order to solve this problem and improve the universities. At the moment, the learning method of university students is evolving toward discussion sessions involving fellow students and presentations utilizing multimedia facilities. In response to these changes, a new type of independent space has appeared, which is called the Group Study Room. In this study, we analyze the spatial characteristics of the Group Study Room. Also, through an IPA(Importance Performance Analysis), this study tries to examine the relationship between the spatial characteristics and users' satisfaction. This analysis is expected to reveal the importance of the spatial characteristics of the group study rooms from the users' point of view. This research can be used for facility planning in universities in the future. The primary aim of this study is to analyze the physical environment of the Group Study Rooms of K university. The secondary aim of this study is to manifest the characteristics of these new learning spaces and to check the space elements of the group study rooms for the sake of efficient planning and management.

• Journal of Energy Engineering
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• v.24 no.4
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• pp.183-191
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• 2015

Studies on the environment-friendly and permanent low energy saving measure are and will continue to be an eternal challenge. However, the demand is high for the technologies that can save energy significantly in everyday life that produce tangible benefits for the users by applying saving factors and that anyone can access easily when it comes the related procedure. Government policies related to the improvement of energy effect in the existing building structure are characterized by complex procedure. Moreover, cost required and reliability issue emerge when request is made to an expert. Accordingly, this study seeks to present energy improvement plan that can be utilized simply and conveniently at any place, any time by enabling customized design according to individual taste by enabling energy change amount and grade prediction when the users select only the part that they want to replace by using a simple program.

• Journal of Communications and Networks
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• v.16 no.2
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• pp.227-237
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• 2014

Throughput scaling laws for two coexisting ad hoc networks with m primary users (PUs) and n secondary users (SUs) randomly distributed in an unit area have been widely studied. Early work showed that the secondary network performs as well as stand-alone networks, namely, the per-node throughput of the secondary networks is ${\Theta}(1/\sqrt{n{\log}n})$. In this paper, we show that by exploiting directional spectrum opportunities in secondary network, the throughput of secondary network can be improved. If the beamwidth of secondary transmitter (TX)'s main lobe is ${\delta}=o(1/{\log}n)$, SUs can achieve a per-node throughput of ${\Theta}(1/\sqrt{n{\log}n})$ for directional transmission and omni reception (DTOR), which is ${\Theta}({\log}n)$ times higher than the throughput with-out directional transmission. On the contrary, if ${\delta}={\omega}(1/{\log}n)$, the throughput gain of SUs is $2{\pi}/{\delta}$ for DTOR compared with the throughput without directional antennas. Similarly, we have derived the throughput for other cases of directional transmission. The connectivity is another critical metric to evaluate the performance of random ad hoc networks. The relation between the number of SUs n and the number of PUs m is assumed to be $n=m^{\beta}$. We show that with the HDP-VDP routing scheme, which is widely employed in the analysis of throughput scaling laws of ad hoc networks, the connectivity of a single SU can be guaranteed when ${\beta}$ > 1, and the connectivity of a single secondary path can be guaranteed when ${\beta}$ > 2. While circumventing routing can improve the connectivity of cognitive radio ad hoc network, we verify that the connectivity of a single SU as well as a single secondary path can be guaranteed when ${\beta}$ > 1. Thus, to achieve the connectivity of secondary networks, the density of SUs should be (asymptotically) bigger than that of PUs.

• Journal of the Korea Society of Computer and Information
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• v.12 no.1 s.45
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• pp.177-188
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• 2007

A star schema consists of a central fact table, which is surrounded by one or more dimension tables. Each row in the fact table contains a multi-part primary key(or a composite foreign key) along with one or more columns containing various facts about the data stored in the row. Each of the composit foreign key components is related to a dimensional table. The combination of keys in the fact table creates a composite foreign key that is unique to the fact table record. The composite foreign key, however, is rarely unique to the fact table retold in real-world applications, particularly in financial applications. In order to make the composite foreign key be the determinant in real-world application, some precalculation might be performed in the SQL relational database, and cached in the OLAP database. However, there are many drawbacks to this approach. In some cases, this approach might give users the wrong results. In this paper, an approach to fact table modeling and related MDX query composing, which can be used in real-world applications without performing any precalculation and gives users the correct results, is proposed.

• Journal of Korean Library and Information Science Society
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• v.52 no.3
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• pp.239-266
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• 2021

This study aimed to analyze the usage behaviors of university students seeking and sharing everyday life information through an online community called Everytime. The study was designed based on everyday life information-seeking and activity theory models, and students from various universities were interviewed using a qualitative research method. Findings showed that Everytime users perceive Everytime as a valuable online community for pursuing and sharing everyday life information. It was primarily used to search for university life information, such as academic calendar, class, and graduation, and health, restaurants, and housing. In the case of the freshmen and sophomores who entered during the COVID-19 pandemic, their dependence on Everytime was high, and juniors and seniors who experienced university life before COVID-19 also responded that Everytime is one of the essential sources of information in university life. Although Everytime provides quick and valuable information, users mentioned the moral hazard as a major factor hindering the active use of Everytime. The results of this study are expected to be used as primary data for informatics research on the online community of college students and the development and operation of online communities for university students.