• Steel and Composite Structures
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• 제45권6호
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• pp.895-905
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• 2022

Composite flooring systems consisting of cold-formed steel joists and reinforced concrete slabs offer an efficient, lightweight solution. However, utilisation of composite action to achieve enhanced strength and economical design has been limited. In this study, finite element modelling was utilised to create a three-dimensional model which was then validated against experimental results for a composite flooring system consisting of cold-formed steel joists, reinforced concrete slab and steel bolt shear connectors. This validated numerical model was then utilised to perform parametric studies on the performance of the structural system. The results from the parametric study demonstrate that increased thickness of the concrete slab and increased thickness of the cold formed steel beam resulted in higher moment capacity and stiffness of the composite flooring system. In addition, reducing the spacing of bolts and spacing of the cold formed steel beams both resulted in enhanced load capacity of the composite system. Increasing the concrete grade was also found to increase the moment capacity of the composite flooring system. Overall, the results show that an efficient, lightweight composite flooring system can be achieved and optimised by selecting suitable concrete slab thickness, cold formed beam thickness, bolt spacing, cold formed beam spacing and concrete grade.

• International Journal of Control, Automation, and Systems
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• 제6권5호
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• pp.651-659
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• 2008

Autoreclosing techniques have been used in power systems to maintain system stability and continuity of supply. Environmental and economical issues have driven significant increases in the development of distributed generation (DG). DG connected to distribution systems, however, may impose negative influences with respect to power quality, protection, and stability, because DG can cause some challenges to protection, especially to reclosing. For this reason, in order to improve the reliability and safety of the distribution system, the rules and guidelines suggest that the DG system needs to be rapidly disconnected from the system before reclosing. We present, in this paper, an adaptive reclosing algorithm considering the DG. The algorithm consists of an angle oscillation's judgment, the emergency extended equal-area criterion (EEEAC), the calculation of an optimal reclosing time, and a reconnection algorithm. Our simulation results for three different DG technologies with Electromagnetic Transient Program (EMTP) indicate that we can maintain transient stability while the DG is protected against disturbances.

• 수산해양기술연구
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• 제50권1호
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• pp.75-82
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• 2014

In vibration analysis of ships, the principle aim is to determine the natural frequencies and excitation frequencies, and use this information to avoid resonances and vibration damage. The simplest method is to prevent resonance conditions, which is effective as long as the natural frequencies and excitation frequencies can be regarded as independent from environmental conditions. For ships that use electric propulsion systems, the sources of vibration are reduced compared with those caused by a diesel engine or other combustion-based propulsion systems. However, the frequency spectrum of these vibrations may be different; therefore, to understand the characteristics of the electric propulsion, we also should investigate how the ship responds to these vibrations. We focused on a 1,000-ton deadweight (DWT) ocean-research vessel using an electric propulsion system and analyzed the response to vibration.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권12호
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• pp.3960-3975
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• 2022

To analyze and compare the most influencing factors on cloud computing adoption (CCA) in the healthcare organization, a systematic review and meta-analyses of studies was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Cochrane collaboration recommendations. A search of PubMed, ScienceDirect, Springer, Wiley Online, and Taylor & Francis Online digital libraries (From inception to January 19, 2022) was performed. A total of 17 studies met the defined studies' inclusion and exclusion criteria. Statistical significance difference favoring most influencing factors on CCA were (MD 0.76, 95% CI -1.48 - 3.01, p <0.00001, I² = 90%), (MD 1.40, 95% CI -4.76 - 7.55, p < 0.00007, I² = 97%) (MD 0.17, 95% CI -2.69 - 3.03, p<0.00001, I² = 96%) for technology vs. organizational, technology vs. environmental and business vs. human factors, respectively. Organizational and environmental factors had greater impacts on CCA compared with technological factors. Moreover, business factors were more influential than the human factors.

• 경영과학
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• 제15권2호
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• pp.83-90
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• 1998

Today, ERP becomes very popular as a vehicle of implementing an integrated information system since this package not only facilitates reengineering but also provides the function of generating consolidated financial statements. Yet a successful introduction strategy on the integrated information system needs to be set up because ERP has weaknesses as well as strengths. The strengths include the prompt reaction to environmental changes, the integrated management of information, the adoption of open systems, and the selection of modules according to functionsl However, the weaknesses of ERP include the provision of only basic functions, the development of package on international standard processes, and possible disadvantages to small and medium-sized firms. This paper is to suggest recommendations on the implementation strategy of ERP as an integrated information system. According to the case study with Firm A that has successfully implemented an ERP package, the most significant advantage of adopting ERP was that Firm A was able to implement an integrated information system for only six months. Finally, this research generates suggestions, such as the importance of the project team structure, the sufficient amount of time for education, and the minimization of the package modification.

• Journal of Information Processing Systems
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• 제13권5호
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• pp.1358-1371
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• 2017

Dynamic thermal rating (DTR) system is an effective method to improve the capacity of existing overhead line. According to the methodology based on CIGRE (International Council on Large Electric systems) standard, ampacity values under steady-state heating balance can be calculated from ambient environmental conditions. In this study, simulation analysis of relations between parameters and ampacity is described as functional dependence, which can provide an effective basis for the design and research of overhead transmission lines. The simulation of ampacity variation in different rating scales is described in this paper, which are determined from real-time meteorological data and conductor state parameters. To test the performance of DTR in different rating scales, capacity improvement and risk level are presented. And the experimental results show that the capacity of transmission line by using DTR has significant improvement, with low probability of risk. The information of this study has an important reference value to the operation management of power grid.

• 환경영향평가
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• 제10권2호
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• pp.99-108
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• 2001

This study was performed to develop an information processing system for the sound conservation of soil and groundwater resources. The system contains numerical models and geographic information systems for underground flow and contamination. Multidimensional Finite Element Model for Subsurface Environment (MFEMSE) was invented to analyze underground flow and pollution problems of water and gas phases. Newly developed and conventional models (MODFLOW, MOC3D, MT3D, PMPATH, PEST, UCODE) were integrated with GIS (ArcView) for the construction of an integrated information management system of subsurface environment. This system was applied to the management of three mineral water companies located in clean high mountain basin. Desirable management criteria and operational strategies were suggested using this system. The system was constructed to be applied for the broad sense of decision supporting tools in related topics of this study, so that it can be used not only for the prevention regulations, but also for clean up projects.

• Asian Journal of Atmospheric Environment
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• 제2권1호
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• pp.60-67
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• 2008

The spatial limitations of urban environments in general lead to invention and design of a wide range of underground transportation systems such as subways, underground roads and paths, etc. Among them, the application of subway systems in metropolitan cities is most commonly observed to ease those confronted difficulties on this purpose. It in turn leaves passengers and workers to be exposed to indoor air potentially polluted by various sources existing in this underground environment. Specifically when considering the IAQ in a subway station, there exist many IAQ-related parameters to be counted either as individual or as integrated exposures. In this study, a model system has been developed to manage the general IAQ in a subway station. Field survey and $CO_2$ measurements were initially conducted to analyze and understand the relationship between the indoor and outdoor air quality while considering the internal pollution sources such as passengers, subway trains, etc. The measurement data were then employed for the model development with other static information. For the model development, the algorithm of simple continuity was built and applied to model the subway IAQ concerned. In this paper, the recent updated draft version of model developed will be reported and demonstrated.

• 산업경영시스템학회지
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• 제27권4호
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• pp.59-68
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• 2004

Recently, shifting channel power is forcing supply chain to take back products. As you can imagine returned product has always been a problem for all parties in the supply chain due to the disruption in operations and a headache in processing returned products. Therefore, every member of supply chain should respond to reverse logistics activities particularly for the return handling process. Under such a strong demand of efficient and cost effective reverse logistics activities, particularly for the return handling process, the information system should be implemented and participated in intensively. This study analyzed the reverse logistics information factors for environmental conscious logistics system limited to returns from customers/consumers. The results provide reverse logistics information factors based on the return handling process which can be used as benchmarking for companies seeking implementation of an efficient return handling system.

• Advances in Computational Design
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• 제4권2호
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• pp.155-177
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• 2019

Operation and Maintenance (O&M) phase is the main contributor to the total lifecycle cost of a building. Previous studies have described that Building Information Models (BIM), if available with detailed asset information and their properties, can enable rapid troubleshooting and execution of O&M tasks by providing the required information of the facility. Despite the potential benefits, there is still rarely BIM with Mechanical, Electrical and Plumbing (MEP) assets and properties that are available for O&M. BIM is usually not in possession for existing buildings and generating BIM manually is a time-consuming process. Hence, there is a need for an automated approach that can reconstruct the MEP systems in BIM. Previous studies investigated automatic reconstruction of BIM using architectural drawings, structural drawings, or the combination with photos. But most of the previous studies are limited to reconstruct the architectural and structural components. Note that mechanical components in the building typically require more frequent maintenance than architectural or structural components. However, the building mechanical drawings are relatively more complex due to various type of symbols that are used to represent the mechanical systems. In order to address this challenge, this paper proposed a symbol recognition framework that can automatically recognize the different type of symbols in the building mechanical drawings. This study applied vector-based computer vision techniques to recognize the symbols and their properties (e.g., location, type, etc.) in two vector-based input documents: 2D drawings and the symbol description document. The framework not only enables recognizing and locating the mechanical component of interest for BIM reconstruction purpose but opens the possibility of merging the updated information into the current BIM in the future reducing the time of repeated manual creation of BIM after every renovation project.