• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.10
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• pp.3409-3422
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• 2014

The frequency spectrum available for the wireless communication is extremely crowded. In order to improve the spectral efficiency, the two-way relay networks have aroused great attention. A simple $N^{th}$ best-relay selection criterion for the opportunistic two-way relay networks is proposed, which can be implemented easily by extending the distributed timer technique in practice, since the proposed criterion is mainly based on the channel gains. The outage performance of the proposed relay selection scheme is analyzed under the outdated channel state information (CSI), and a tight closed-form lower bound and asymptotic value of the outage probability over Rayleigh fading channels are obtained. Simulation results demonstrate that the tight closed-form lower bound of the outage probability very closely matches with simulated ones in the whole SNR region, and the asymptotic results provide good tight approximations to the simulation ones, especially in the high SNR region.

• Journal of The Korean Digital Architecture Interior Association
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• v.10 no.3
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• pp.87-95
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• 2010

The CM(Construction Manager) of D-university has been seeking the advice of my BIM-team to adopt CM(Construction Management) and BIM best practices to improve project delivery results, and has authored best practice reports for spatial validation, BIM, 3D, 4D and 5D performance. Building Information Modeling(BIM) Process, Integration, and Adoption looks at BIM implementation from a company and project level laying out a process for companies to use BIM. Following this studies, participants will be able to: 1. BIM participants has been creating a BIM process diagram for a project, and has been evaluating and selecting process options for a specific BIM project. 2. BIM participants has been describing the roles and responsibilities of participants in the BIM process, and has been communicating the BIM process to management, colleagues, and project stakeholders. 3. BIM participants has been identified consistent factors influencing BIM return on investment at the project level and the company level, and has been outlining a process for BIM adoption on the project level and company level.

• Journal of Korean Society on Water Environment
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• v.20 no.6
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• pp.641-646
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• 2004

Vehicle emissions from highway landuse include different pollutants such as heavy metals, oil and grease and particulates from fuels, brake pad wear and tire wear. Since highways are impervious and have high pollutant mass emissions from vehicular activity, it is considered as stormwater intensive landuses. Therefore this research was performed to understand the magnitude of first flush and to suggest the criteria of first flush for storm runoff management in highways. The fractions of washed-off mass are very high in first 30% of runoff volume, which suggests a definition of first flush. The washed-off mass stabilizes after 30% of the runoff volume and it is apparent that treatment capacity in the early part of a storm is more valuable than treatment capacity in the later part of the storm. Using the criteria of "high" first flush and "medium" first flush, as 50% of the mass in the first 30% of the volume, and 30 to 50% in the first 30% volume, respectively, more than 30% of the storms showed high first flush. A "first flush friendly" best management practice(BMP), meaning a BMP that can treat a high percentage or all of the initial flow, would be advantageous up to 80% of the events.

• Journal of Construction Engineering and Project Management
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• v.5 no.1
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• pp.1-10
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• 2015

In construction, stakeholders of extended project team play a key role in the overall project performance. Successful integration of stakeholders demands for good management practices at strategic, operational and project levels. Targets and measures to improve the stakeholder performance encourage the creativity and willingness of stakeholders of extended project team to develop the better ways to achieve the project objectives. This paper presents a generic descriptive method, showing how stakeholder's ability and influence impacts on project performance in the construction sector. The findings of a series of interviews with key informants are presented and the following main conclusion is drawn: improving project performance through stakeholder's contribution and measuring their performance can strengthen the project performance. This innovative approach which redefines the process of improving the project performance in construction projects will be of interest to those who intend to manage the projects in practice as well as to those who interested in advancing theory.

• Journal of the Korea Society of Computer and Information
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• v.21 no.12
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• pp.165-171
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• 2016

This study analyzes the relative importance of the introducing factors for the critical success factors in the implementation stage of the lifecycle of ERP system using Delphi technique and Analytic Hierarchy Process(AHP). In the 1st layer of the hierarchy, technical factor is evaluated as the most important factor among organizational, technical, and supplier factors. In the 2nd layer, choosing a proper ERP package is evaluated as the most important factor within 15 factors followed by process-oriented approach, technical suitability, minimized customization, integration and association of system with trading parter, association with legacy systems, and support and involvement of top management. As a result of this analysis enterprise should choose an ERP package that is suitable to its business environment, and make the best use of(take full advantage of) best practice that ERP package provides to optimize the existing business procedure or process(to approach the existing business procedure or process). This study also shows the range of customization of the features provided by the ERP package should be minimized.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.10a
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• pp.866-870
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• 2009

Mobile Health (M-Health) system is a recent term for medical and public health practice supported by mobile devices, such as mobile phones, PDAs, and other wireless devices. Mobile Health system has been successfully establishing at few general hospital in Korea. However, to use diverse devices manufactured by various company cause inoperability, and lack of security disappoints customers often. Although the outstanding health environment, most of hospitals are unavailable to share electronic patient records due to lack of standard protocol to handle the interoperability each other. Health Level 7 (HL7) is the best solution for the problem. In this paper, we will analyse a current M-Health service in terms of security and mobile device, and suggest iPhone for the best device against hospital environment. Also, for keep confidentiality of health information and patient privacy, enhanced security mechanism is introduced. As a consequence, interoperable standard, and most appropriate device for supporting staffs and M-Health performance, and enhanced securirty mechanism will be integrated in order to propose improved M-health model.

• Journal of Korea Multimedia Society
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• v.22 no.6
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• pp.738-747
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• 2019

Both within the country and internationally, discussions about core technologies that will be prominent in future society have been initiated, and software education for the rapidly changing industrial framework has been essential and implemented in earnest. Also, there is an increasing interest in interactive technology and software education where people and people, people and computers, and computers and objects communicate with each other in today's day-to-day life, connected through the digital world. Therefore, it is necessary to investigate the user's field of interest and the best technical education method for teaching how to operate the production tool for implementing the interactive technology. In this study, we utilize the Processing program which is widely used as interactive technology software training and creativity tool to improve the understanding of the interactive technology related to the 4th industrial revolution. This study aims to determine and propose the best method of using a Processing library that can be applied to each major field.

• Earthquakes and Structures
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• v.21 no.5
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• pp.505-514
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• 2021

A formulation based on structural reliability and cost effectiveness is proposed to provide recommendations to select the best retrofit strategy for schools with reinforced concrete frames and masonry walls, among three proposed alternatives. The cost calculation includes the retrofit cost and the expected costs of failure consequences. Also, the uncertainty of the seismic hazard is considered for each school site. The formulation identifies the potential failure modes, among shear and bending forces for beams, and flexure-compression forces for columns, for each school, and the seismic damages suffered by the schools after the earthquake of September 17, 2017 are taken into account to calibrate the damaged conditions per school. The school safety level is measured through its global failure probability, instead of only the local failure probability. The proposed retrofit alternatives are appraised in terms of the cost/benefit balance under future earthquakes, for the respective site seismic hazard, as opposed to the current practice of just restoring the structure original resistance. The best retrofit is the one that corresponds to the minimum value of the expected life cycle cost. The study, with further developments, may be used to develop general recommendations to retrofit schools located at seismic zones.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.285-291
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• 2009

Water is a strategic resource for Singapore due to its small land mass and more than half of the mainland serves as catchment for raw water, including construction sites. Construction site typically involves earthworks and in conjunction with the frequent and intense rainstorm in Singapore, produce runoff of high turbidity due to suspended sediments. The resulting high concentration of suspended sediment in construction site runoff very often leads to aesthetically unpleasant reservoirs and potentially increases the treatment cost of raw water. To mitigate this, the local standard requires the discharged concentration of total suspended solids of construction runoff leaving a construction site to be less than 50mg/l which is a very high standard. This paper will present, examine and discuss particular issues and practices of Singapore's construction industry in meeting this requirement. The focus will be on two areas: Government lead initiatives and industry practices. How the government agencies worked together with the industry professionals to develop a system to ensure meeting of the standard is discussed. In addition, the types of industry practices, including various Best Management Practice to reduce erosion in construction sites and implement effective sedimentation on construction sites are examined.

• Anatomy and Cell Biology
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• v.56 no.4
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• pp.474-481
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• 2023

The dental characteristics created by acquired dental treatments can be used as age estimators. This pilot study aimed to analyze the correlation between the number of teeth observed for dental characteristics and chronological age and to develop new non-invasive age estimation models. Dental features on panoramic radiographs (420 radiographs of subjects aged 20-89 years) were classified and coded. The correlation between the number of teeth for each selected code (codes V, X, T, F, P, and L) and age was observed, and multiple regression was performed to analyze the relationship between them. Eleven regression models with various combinations of dental sextants were presented. The model with the data from both sides of the posterior teeth on both jaws showed the best performance (root mean square error of 14.78 years and an adjusted R² of 0.461). The model with all teeth was the second-best. Based on these results, we confirmed statistically significant correlations between certain dental features and chronological age. We also observed that some regression models performed sufficiently well to be used as adjunctive methods in forensic practice. These results provide valuable information for the design and performance of future full-scale studies.