• Information and Communications Magazine
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• v.31 no.3
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• pp.103-116
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• 2014

This paper proposes the design of Vehicular Cyber-Physical Systems (called VCPS) based on vehicular cloud for smart road networks. Our VCPS realizes mobile cloud computing services where vehicles themselves or mobile devices (e.g., smartphones and tablets of drivers or passengers in vehicles) play a role of both cloud server and cloud client in the vehicular cloud. First, this paper describes the architecture of vehicular networks for VCPS and the delay modeling for the event prediction and data delivery, such as a mobile node's travel delay along its navigation path and the packet delivery delay in vehicular networks. Second, the paper explains two VCPS applications as smart road services for the driving efficiency and safety through the vehicular cloud, such as interactive navigation and pedestrian protection. Last, the paper discusses further research issues for VCPS for smart road networks.

• Journal of KIBIM
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• v.9 no.2
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• pp.11-20
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• 2019

The use of drones and laser scanners have the potential to drastically reduce the time and costs of conventional techniques employed for field survey of cultural heritage buildings. Moreover, point cloud data can be utilized to create an as-built Building Information Model (BIM), providing a repository for consistent operations information. However, BIM creation is not a requisite for heritage buildings, and their technological possibilities and barriers have not been documented. This research explored the processes required to convert a heritage university building to a BIM model, using existing off-the-shelf software applications. Point cloud data was gathered from drones for the exterior, while a laser scanner was employed for the interior of the building. The point clouds were preprocessed and used as references for the geometry of the building elements, including walls, slabs, windows, doors, and staircases. The BIM model was subsequently created for the individual elements using existing and custom libraries. The model was used to extract 2D CAD drawings that met the requirements of Korea's heritage preservation specifications. The experiment showed that technical improvements were needed to overcome issues of occlusion, modeling errors due to modeler's subjective judgements and point cloud data cleaning and filtering techniques.

• Journal of Information Processing Systems
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• v.16 no.1
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• pp.132-144
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• 2020

Cloud computing is an emerging technology based on the concept of enabling data access from anywhere, at any time, from any platform. The exponential growth of cloud users has resulted in the emergence of multiple issues, such as the workload imbalance between the virtual machines (VMs) of data centers in a cloud environment greatly impacting its overall performance. Our axis of research is the load balancing of a data center's VMs. It aims at reducing the degree of a load's imbalance between those VMs so that a better resource utilization will be provided, thus ensuring a greater quality of service. Our article focuses on two phases to balance the workload between the VMs. The first step will be the determination of the threshold of each VM before it can be considered overloaded. The second step will be a task allocation to the VMs by relying on an improved and faster version of the meta-heuristic "simulated annealing (SA)". We mainly focused on the acceptance probability of the SA, as, by modifying the content of the acceptance probability, we could ensure that the SA was able to offer a smart task distribution between the VMs in fewer loops than a classical usage of the SA.

• Journal of KIBIM
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• v.6 no.1
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• pp.9-17
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• 2016

Building information modeling refers to combination or set of technologies and organizational solutions that are expected to increase collaboration in the construction industry and to improve the productivity and quality of the design, construction, and maintenance of buildings. For enhanced communication among project participants, various information which BIM model usually includes is provided, furthermore data which contain exchange of unstructured information is needed. If the extension of BIM standard file format for practical use of design Issue information about collaborative design process is fulfilled, the productivity and quality of design will be improved.

• Proceedings of the Korean Society of Computer Information Conference
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• 2017.01a
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• pp.79-82
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• 2017

IoT devices are interconnected in global network with different functionalities and manage the data transfer in cloud computing. IoT devices can be used anytime, anywhere with any device with different applications and protocols. Same devices but different applications according to end user requirements such as sensors and Wi-Fi devices, reusability of these applications can enhance the development process. However, large number of variations in cloud computing make it difficult the features selection in application because of compatibility issues of devices. In this paper we have proposed multi-Software Product Lines (multi-SPLs) approach to manage the variabilities and commonalities of IoT applications and protocols. Feature modeling is used to manage the commonalities and variabilities of SPL. We proposed that multi-SPLs feature model is more appropriate for modeling of IoT applications and protocols.

• Journal of the Korea Society for Simulation
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• v.32 no.3
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• pp.1-8
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• 2023

Modeling of artificial targets in Synthetic Aperture radar (SAR) mainly simulates radar signals reflected from the faces and edges of the 3D Computer Aided Design (CAD) model with a ray-tracing method, and modeling of the clutter on the Earth's surface uses a method of distinguishing types with similar distribution characteristics through statistical analysis of the SAR image itself. In this paper, man-made targets on the surface and background clutter on the terrain are integrated and made into a three-dimensional (3D) point cloud scatterer model, and SAR image were created through computational signal processing. The results of the SAR Stripmap image generation of the actual automobile based SAR radar system and the results analyzed using EM modeling or statistical distribution models are compared with this 3D point cloud scatterer model. The modeling target is selected as an bridge because it has the characteristic of having both water surface and ground terrain around the bridge and is also a target of great interest in both military and civilian use.

• Journal of Information Technology Applications and Management
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• v.18 no.4
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• pp.1-20
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• 2011

The recent development of mobile devices, including smartphones has maximized the user's convenience. This phenomenon has triggered the specification and activation of mobile cloud service and transformed the user's information usage and communication means. Despite such development of new technology, there is little understanding of mobile cloud. Therefor, in order to help the understanding of the usage of mobile cloud computing technology, this study developed the research model based on the UTAUT (the Unified Theory of Acceptance and Usage of Technology) model. The proposed research model included five external determinants, such as Interoperability, Information Organization, Adequacy, Information Security and Context Awareness, along with the moderating effects of Job Relevance, and empirically proved their influence on the user's job performance. This study proved the research model by analyzing the data collected from 287 copies of survey with the structural equation modeling approach. The result showed that all determinants, except Information Security have positive impact on the usage of mobile cloud computing technology. Thus, this study can compliment the limitations of previous research, suggest a new direction to analyze the user's perspective in the related research on mobile cloud and build a theoretical foundation for the further development of mobile cloud.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.34 no.1
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• pp.83-102
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• 2024

Recently, as the use of the cloud increases year by year and remote work within the enterprise has become one of the new types of work, the security of the cloud-based remote work environment has become important. The introduction of zero trust is required due to the limitations of the existing perimeter security model that assumes that everything in the internal network is safe. Accordingly, NIST and DoD published standards related to zero trust architecture, but the security requirements of that standard describe only logical architecture at the abstract level. Therefore, this paper intends to present more detailed security requirements compared to NIST and DoD standards by performing threat modeling for OpenStack clouds. After that, this research team performed a security analysis of commercial cloud services to verify the requirements. As a result of the security analysis, we identified security requirements that each cloud service was not satisfied with. We proposed potential threats and countermeasures for cloud services with zero trust, which aims to help build a secure zero trust-based remote working environment.

• Proceedings of the KSRS Conference
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• 1999.11a
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• pp.100-102
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• 1999

We have analyzed AVHRR global data set for obtaining aerosol and cloud microphysical parameters, i. e., optical thickness and size index of particle polydispersions. From the results, it is found that the cloud optical thickness increases with increasing aerosol column number, which seems to be caused mainly by decreasing cloud particle radius, The cloud liquid water path was observed to be relatively constant without a significant dependence on the aerosol number. Further comparison of the satellite results with a general circulation model simulation.

• Korean Journal of Computational Design and Engineering
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• v.17 no.5
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• pp.342-352
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• 2012

As a futuristic construction model, building information model (BIM) based project management system (PMIS) and mobile BIM simulator apps have been showing visible sign. However, researches on the BIM based 3D simulator using mobile device are hard to find result from limitation of mobile device (slow speed at huge 3D file, display size, and etc.) and undefined standard of business processes. Therefore, this research aims at studying application of mobile BIM apps based on cloud computing. Total 8 BIM cloud apps were selected and analyzed in the 5 application feasibility characteristics (speed, view, inquiry, markup, and usability). This research would be essential phase to construct BIM based mobile project management system using cloud computing in the future.