• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.8
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• pp.2606-2626
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• 2022

In this paper, a unmanned aerial vehicle (UAV) access deployment algorithm is proposed, which is based on an improved virtual force model to solve the poor coverage quality of UAVs caused by limited number of UAVs and random mobility of users in the deployment process of UAV base station. First, the UAV-adapted Harris Hawks optimization (U-AHHO) algorithm is proposed to maximize the coverage of users in a given hotspot. Then, a virtual force improvement model based on user perception (UP-VFIM) is constructed to sense the mobile trend of mobile users. Finally, a UAV motion algorithm based on multi-virtual force sharing (U-MVFS) is proposed to improve the ability of UAVs to perceive the moving trend of user equipments (UEs). The UAV independently controls its movement and provides follow-up services for mobile UEs in the hotspot by computing the virtual force it receives over a specific period. Simulation results show that compared with the greedy-grid algorithm with different spacing, the average service rate of UEs of the U-AHHO algorithm is increased by 2.6% to 35.3% on average. Compared with the baseline scheme, using UP-VFIM and U-MVFS algorithms at the same time increases the average of 34.5% to 67.9% and 9.82% to 43.62% under different UE numbers and moving speeds, respectively.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.8 no.4
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• pp.163-169
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• 2009

Recently, the concern of the FTA (Free Trade Agreement) have shifted to the promotion of the professional service's trade via the bilateral and reciprocal agreement of its professional laws. In the construction industry, this policy has intended to make the standardization of the construction manager's profession in the world. The purpose of this paper is 1) first to define the general model of professions in the U.S., UK and Japan, 2) then to declare the construction manager's model of the profession in them to apply the general model of professions, and 3) finally to analyze the identity of Korean construction managers and acquirement of its construction manager's law comparing with construction manager's model of the profession in the U.S., UK and Japan.

• Journal of the Ergonomics Society of Korea
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• v.31 no.1
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• pp.63-76
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• 2012

Objective: The main objective of this study is to propose a user-centered assessment metric for ubiquitous services. Background: As the ubiquitous era took off, the interactions between ubiquitous services and users have come to take an important position. It is essential to conceptualize a new assessment model that considers human-system interaction capability with a user-centered design perspective. Method: The evaluation model for the interactivity of ubiquitous service was approached from the concept of usability and inter-personality of services. As a validation study, suggested assessment metric was utilized to evaluate the u-Home service. Priority weighting of each assessment metric was derived using the quantification type-I analysis. Results: To evaluate interactivity, this study suggested a quantitative metric for user testing performed after classifying the interactivity characteristics to contextualization; ubiquity; user experience; and service capability. Conclusion: This study suggest the metric for the ubiquitous service that are experienced in real life, and introduced the concept of ubiquitous service interactivity. Application: The suggested evaluation metric can be used to evaluate interactivity level of ubiquitous service and identify the potential problem and usability requirements at the early stage of service development.

• Convergence Security Journal
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• v.5 no.4
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• pp.33-40
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• 2005

As e-learning studying is activated, learner's requirement increased. Therefore, need correct e-learning model augmented requirement of learner and new ubiquitous surrounding. In this treatise when, proposed to supplement studying contents relationship conversion service and cooperation studying service function to LMS that analyze existing e-learning model's limitation for ubiquitous environment e-learning model that can study regardless of, ubiquitously some contents and do based on SCORM ubiquitous-network and next generation sensor technology etc. Learning form conversion service senses a learner's surrounding situations and recognize his/her body condition using smart sensor technology and provides the learner with contents in the optimal form. Using sensing projects like Orestia and SOB, users can more effective collaborative learning service.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1326-1331
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• 2005

A product is designed through the collaboration among engineers in several fields such as design, analysis, and manufacturing. These series of functions are performed repeatedly during the design process. An easy access and exchange of the model data is one of the important elements that help to shorten production development time. Especially, the importance of data exchange between CAD and CAE applications is increasing in the field of verification and estimation of the products. However, information and knowledge of model which is generated by a CAD software cannot be transferred by a function of CAE software, as an exchange of product data between CAD and CAE applications. It causes a delay in design analysis and eventually discourages a designer's effort in improving his design. Therefore, we need to integrate a commercial CAD and CAE applications effectively and to use the same interface on a product model obtained in a distributed environment. This paper shows how to implement a model exchange between CAD and CAE by a web-service and how to provide a communication environment among engineers.

• The KIPS Transactions:PartD
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• v.18D no.3
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• pp.185-196
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• 2011

As the Korean Ministry for Health and Welfare announced the likelihood to revise the legislative limit for healthcare telemedicine, u-Healthcare service through IPTV emerged among these business models. However, in spite of many advantages such as treatment improvement, service quality enhancement, and treatment usefulness, most medical trials grafted with IT have not accepted yet. This points out not only that law and institutional environment has not prepared, but also that policy maker neglect the preparation of the strategies through the study on user acceptance. The purpose of this study is to verify the relationship for IPTV quality based Healthcare on satisfaction and intention to use. The results identify that IPTV technology quality for its convenience, contents quality for its completeness, and the quality for healthcare services give significant effect to satisfaction. In addition the study indicates that overall qualities of IPTV technology, contents, and healthcare service, significantly impact on satisfaction respectively and that the satisfaction may lead to the intention to use of this service.

• The Journal of the Korea Contents Association
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• v.10 no.7
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• pp.88-97
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• 2010

Recently the more convenient services are provided to people in the city in line with the change of city paradigm and the recent development of ubiquitous. For example, Information on bus arrivals an effective advertisement the combination of high technology and departures through smart-phones. However, in respect of the mobile advertisement, because of difficulties such as the means of transferring the mass storage data or the burden of communication charges. there need means to improve such difficulties. This study has been conducted aiming to overcome such difficulties. This study suggests the strategic differentiation plan through the analysis of the media characteristics such as real time service information when in traveling, U-Bus business model in the category of mobile advertisement, etc. and also the concrete system establishment plan from the operation center via network to the delivery of the advertisement through vehicle terminals. In respect that this study suggests the implications as a practical business model through the fusion of high technology and diverse media. It has great significance.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.8B
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• pp.897-903
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• 2011

In this paper, we consider a future u-Army network with VoIPv6 and evaluate the performance based on the large-scale simulation. The target model chosen in our paper is extended to an division network from several unit networks in which the scope of the performance simulation was limited with the small experiment network[l]. The simulation model is based on several practical scenarios and the actual condition of the division network with some assumption. The evaluated performance results will help to predict whether a future u-Army network meet the real-time service or not, and to design the network suitable for military condition and requirements.

• Journal of Korean Society for Quality Management
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• v.29 no.4
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• pp.1-17
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• 2001

The characteristics of Telecommunication Industry encompass not only hardware and software but also the service aspect of them. One way to improve the industry up to the international level in terms of hardware and software as well as service aspect is to comply with tile TL 9000 standard, which was established by QUEST Forum, the group consisted of U.S. communication industry, based on the ISO 9000 Quality Management System. In this study, design, establishment, implementation, maintenance and improvement of quality system for domestic telecommunication industry are thoroughly investigated based on TL 9000 standard, with its LCM(Life Cycle Model) model and measurements. Also, Process Approach is suggested to help the industry realize the system to meet its specific needs. In addition, specific examples with the successful certification to TL 9000 standard are presented.

• Science of Emotion and Sensibility
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• v.10 no.3
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• pp.481-489
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• 2007

The purpose of this study was to investigate whether there were differences in sound quality among telecommunication service providers(SPs). To avoid the influence of brand of SPs and mobile phone manufacturer, a series of structured experiments was planed. Possible source of sound difference were tested such as specific genres of music, contents providers, mp3 players for PC, and mobile phone manufacturers. The results show there are differences of sound quality among telecommunication service providers(SPs). But the difference comes from contents, mobile phone, and MP3 player for PC. The same model of mobile phone from the manufacturer sounded differently depending on telecommunication service providers(SPs). The genre of music did not show consistent difference in sound quality.