• Journal of Advanced Navigation Technology
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• v.20 no.6
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• pp.503-510
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• 2016

In recent years, owing to the growing user demand for the two-way internet service based on the move global broadband communications, a new type of satellite terminal has developed, known as earth station in motion (ESIM). This service was required by Resolution 158 (WRC-15) to study on the coexistence with the co-primary fixed service (FS) in 27.5-29.5 GHz as a FSS uplink. In this paper, four scenarios was introduced to account for the antenna pointing error and the azimuth for an analysis on the sharing between ESIM and FS. From analysis results, the required separation distance between two systems should be about 32~52 km according to the elevation angles of $20^{\circ}{\sim}40^{\circ}$ using thresholds of 5% and 10% outage probability. Therefore, it is necessary to control the azimuth angle due to a moving terminal as well as the pointing error of ESIM to minimize the required separation distance and to protect the co-primary FS.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.4
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• pp.1241-1249
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• 2014

This study presents preferences factors analysis of Car-sharing in Suwon. Approximately, 60% of the citizens prefer car-sharing and consider using it. The results of analysis by factors show higher preferences in these groups of travelers: man, younger, a resident of detached house and efficiency apartment, user of public transportation who finds it uncomfortable, traveler without vehicles, and traveler using car 1 to 3 times a week. The potential demand for car-sharing was highest in the residential areas and around the stations. Travelers prefer to pay the fee by the hour, which the fair value was 7,967 won. For the trip purpose of business, shopping and leisures, car-sharing is more preferred than taxi and rental cars. Findings will contribute to determining the direction of policy for the car-sharing.

• Fashion & Textile Research Journal
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• v.17 no.6
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• pp.932-941
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• 2015

An aging population and increasing consumer demand for high-quality and innovative new products are key drivers for growth in the cosmeceutical industry. Cosmeceuticals are defined as products with biologically active ingredients that have a measurable effect on the user. This study explored the effects of shopping orientation and store attributes on impulse buying behavior for cosmeceuticals. We obtained 437 usable questionnaires from university students who had purchased cosmeceutical products. Data analysis was conducted using confirmatory factor analysis and structural equation modeling analysis via AMOS 18.0. The findings were: 1) hedonic shopping orientation and convenience shopping orientation had positive effects on product efficacy and promotion of the cosmeceutical store 2) brand shopping orientation had a positive effects on store atmospheric, skin care service, and brand of the cosmeceuticals store and 3) product efficacy and promotion of store attributes had a direct effect on impulse buying behavior for cosmeceuticals. Consumers who tended to enjoy the shopping to refresh themselves and to experience convenient shopping were likely to purchase cosmeceuticals impulsively, which mediated by the store attributes (product efficacy and promotion). Therefore, we confirmed partly causal relationships among the shopping orientation, store attributes, and impulse buying behavior of cosmeceuticals. Both managerial and theoretical implication for practitioners and researchers were discussed for managing product information more efficiently along with promotion strategies to trigger cosmeceuticals consumers in the context of shopping.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.11
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• pp.5301-5323
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• 2017

Small cell deployment offers a low-cost solution for the boosted traffic demand in heterogeneous cellular networks (HCNs). Besides improved spatial spectrum efficiency and energy efficiency, future HCNs are also featured with the trend of network architecture convergence and feasibility for flexible mobile applications. To achieve these goals, dual connectivity (DC) is playing a more and more important role to support control/user-plane splitting, which enables maintaining fixed control channel connections for reliability. In this paper, we develop a tractable framework for the downlink SINR analysis of DC assisted HCN. Based on stochastic geometry model, the data-control joint coverage probabilities under multi-frequency and single-frequency tiering are derived, which involve quick integrals and admit simple closed-forms in special cases. Monte Carlo simulations confirm the accuracy of the expressions. It is observed that the increase in mobility robustness of DC is at the price of control channel SINR degradation. This degradation severely worsens the joint coverage performance under single-frequency tiering, proving multi-frequency tiering a more feasible networking scheme to utilize the advantage of DC effectively. Moreover, the joint coverage probability can be maximized by adjusting the density ratio of small cell and macro cell eNBs under multi-frequency tiering, though changing cell association bias has little impact on the level of the maximal coverage performance.

• Proceedings of the Safety Management and Science Conference
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• 2006.11a
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• pp.415-426
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• 2006

Many technical and nontechnical issues hinder enterprise wide workflow management. The most significant technical issue is the inability to deal with the heterogeneity among users, workflow types, and WFMSs. Not all users demand the same workflow functionality, so user interfaces of different levels of sophistication are required. Because workflow types cannot always be fully predefined, they often need to be adjusted or extended during execution. Unlike relational database management systems, however, each WFMS often has differing workflow metamodels. This leads to incompatibility between WFMSs, making integration into an environment comprising many heterogeneous WFMSs a troublesome and sometimes impossible task. Current Workflow system consists mainly of Database system. It contains some problems like that the integration relationship among system processes cant be expressed properly. This research has been focused on two phases that should be considered in the Workflow system. First of all, the first phase is the analysis phase; one of its role is to figure out independent execution task unit(Workflow component). The second phase is design phase that provides with the framework to execute these task units actively. The Workflow component extraction method in the analysis phase uses a analysis method called C-C Net and, in the design phase, the architecture that makes the these Workflow component executed actively is provided. Through this research, each process is divided into a task unit and more effective Workflow system could be formed by executing these units actively. Current system layer calls task units, on the other hand, the Workflow system this research implemented provides with the architecture that places a layer between them that controls task units actively.

• Journal of the Korea Society of Computer and Information
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• v.14 no.5
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• pp.167-174
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• 2009

The meaning of Database in order to manage the data which is huge in the meeting of the record which logically had become the fire tube or file 'efficiently' is widely used from the place which controls a many double meaning data. Like this data base it creates, it manages, the programs which send an answer back according to demand of the user as DBMS it calls. Like this it will be able to grasp the quality level of the data base software product which is important index from the research which index it buys it defined. Also, in order to produce the result of index it selects the collection item which is necessary and collection and analysis it leads and what kind of defect types occur substantially mainly, and it confirmed and the test and evaluation model in about data base software and a tentative instance it developed it analyzed.

• Transactions of the Korean hydrogen and new energy society
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• v.35 no.2
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• pp.146-151
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• 2024

The demand for research on materials with excellent cryogenic strength and ductility has been increasing, particularly for applications such as liquid hydrogen (20 K) storage tanks. To effectively utilize liquid hydrogen, a system capable of maintaining and operating at 20 K is essential. Therefore, preliminary research and verification of the cooling system are crucial. In this study, a heat transfer analysis was conducted on a cooling system to meet the cryogenic environment requirements for cryogenic hydrogen chamber, which are conducted at liquid helium temperatures (4 K). The cooling mechanism in a helium cooling system was examined using numerical analysis. The numerical cooling trends were compared with experimentally obtained cooling results. The good agreement between numerical and experimental results suggests that the numerical approach developed in this study is applicable over a wide range of cryogenic systems.

• Economic Analysis
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• v.25 no.2
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• pp.54-95
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• 2019

The purpose of this study is to analyze quantitatively and qualitatively the effects of the increase in online shopping and its effects on real-world commercial outlets. The empirical analysis of this study is based on the results of "Census on Establishments" and "Online Shopping Survey" that cover 15 years, from 2002 to 2016. According to the results of this study, the increase in the number of online transactions affects the decrease in the number of stores in the real-world retail sector. However, non-specialized large stores and chain convenience stores showed an increase in the number of stores. In addition, the number of F&B stores increased the most in line with the increase in online transactions. This is because the increase in online transactions and in internet users led to the use of more delivery applications and the introduction of popular places on blogs or through social media. Street-level rents for medium and large-sized locations increased. In other words, it is seen that the demand for differentiated real-world stores that provide a good user experience increases, even though online transactions also increase. These results suggest that real-world stores should provide good user experiences in their physical locations with a certain size and assortment of goods.

• Korean Journal of Construction Engineering and Management
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• v.25 no.1
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• pp.50-61
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• 2024

The market for compact houses is growing due to the demand for floor plans prioritizing user needs. However, clients often have difficulty communicating their spatial requirements to professionals including architects because they lack the means to provide evidence, such as spatial configurations or cost estimates. This research aims to create a framework that can translate sketched data-driven spatial requirements into 3D building components in BIM models to facilitate spatial understanding and provide building performance analysis to aid in budgeting in the early design phase. The research process includes developing a process model, implementing, and validating the framework. The process model describes the data flow within the framework and identifies the required functionality. Implementation involves creating systems and user interfaces to integrate various systems. The validation verifies that the framework can automatically convert sketched space requirements into walls, floors, and roofs in a BIM model. The framework can also automatically calculate material and energy costs based on the BIM model. The developed frame enables clients to efficiently create 3D building components based on the sketched data and facilitates users to understand the space and analyze the building performance through the created BIM models.

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