• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.11a
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• pp.222-223
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• 2014

According to the improvement of IT technology, an enhanced efficiency of management system in the construction industry is expected since a quotation system with BIM (Building Information Modeling) technique effectively estimates construction materials. For an enhanced efficiency of management system, related guidelines, standards, and manuals based on BIM are required, but the lack of this information causes difficulty to utilize in practice. In the paper, the satisfaction analysis was performed in order to promote the completeness of construction estimating manager that can be presented criteria and details of BIM-based quantity-takeoff, classification criteria.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.3
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• pp.303-308
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• 2014

Aircraft are an indispensable mode of modern transportation. They are also used as in a wide variety of other fields. For example, aircraft are used for accommodating passengers, carrying freight, and for military reconnaissance. Aircraft ground operations include landing and taking off. During landing, a higher load is applied to the landing gear than during takeoff. The landing gear should absorb impact energy and prevent damage to the main body of the aircraft in the case of an accident. In this study, simulations were performed for two types of plate-spring-type landing gear: that made of composite materials and that constructed with aluminum. The structural safety of landing gear made of each material was also evaluated.

• Advances in aircraft and spacecraft science
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• v.8 no.1
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• pp.17-30
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• 2021

This is an investigation for a more electric regional aircraft, considering the ATR 72 aircraft as an example and the electrification of its four double slotted flaps, which were estimated to require an energy of 540 Wh for takeoff and 1780 Wh for landing, with a maximum power requirement of 35.6 kW during landing. An analysis and evaluation of three energy harvesting systems has been carried out, which led to the recommendation of a combination of a piezoelectric and a thermoelectric harvesting system providing 65% and 17%, respectively, of the required energy for the actuators of the four flaps. The remaining energy may be provided by a solar energy harvesting photovoltaic system, which was calculated to have a maximum capacity of 12.8 kWh at maximum solar irradiance. It was estimated that a supercapacitor of 232 kg could provide the energy storage and power required for the four flaps, which proved to be 59% of the required weight of a lithium iron phosphate (LFP) battery while the supercapacitor also constitutes a safer option.

• Journal of the Korean Society of Industry Convergence
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• v.27 no.1
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• pp.77-86
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• 2024

Urban Air Mobility (UAM) is considered the future of transportation, offering solutions to urban challenges and reducing environmental issues through the use of electric power and leveraging the sky as a new transportation corridor. UAM has diverse applications, including passenger and goods transportation, emergency rescue operations, patient transfers, and urban tourism. Furthermore, it is poised to revolutionize the transportation landscape, impacting existing infrastructures such as roads and parking lots, along with autonomous vehicles. The UAM industry is anticipated to exert a significant impact on various sectors, including airframe manufacturing, the development of new materials (e.g., fuel cells and batteries), and even the defense industry, resulting in substantial economic benefits. Consequently, conducting proactive research and setting industry standards for UAM takeoff and landing infrastructure is crucial for securing market leadership. In this regard, the case of Pontoise-Cormeiles, France, stands out as it achieved the world's inaugural successful demonstration of a vertiport before the 2024 Olympics. This achievement has significant implications for our preparations for the commercialization of UAMs. Thus, a detailed review of the French vertiport construction case in this study will serve as a foundation for guiding the planning and operation of UAMs in South Korea, particularly in anticipation of upcoming demonstration tests.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.738-743
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• 2008

Recently BIM is utilized to improve productivity for Life Cycle Cost of construction projects. Therefore, the establishment of BIM process by each construction project is a necessary element. However, cases and the pertinent researches that BIM process by each project is established are still not enough in Korea. The study proposed construction of BIM process through how to set up BIM application, how to organize a BIM team, how to set up a family and modeling method in the early stage. To achieve the purpose, the study examined application ability of BIM process by carrying out basic setting and modeling work through pilot study model, examination of the amount of materials and information interchange with IFC. The study attempted making a foundation of domestic BIM guideline construction through the above examination.

• Korean Journal of Construction Engineering and Management
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• v.12 no.2
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• pp.111-120
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• 2011

High-rise buildings have recently increased over the residential, commercial and office facilities, thus an understanding of construction cost for high-rise building projects has been a fundamental issue due to enormous construction cost as well as unpredictable market conditions and fluctuations in the rate of inflation by long-term construction periods of high-rise projects. Especially, recent violent fluctuations of construction material prices add to problems in construction cost forecasting. This research, therefore, develops a time-series model with the Box-Jenkins methodologies and material prices time-series data in Korea in order to forecast future trends of unit prices of required materials. BIM (Building Information Modeling) approaches are also used to analyze injection time of construction resources and to conduct quantity takeoff so that total material price can be forecasted. Comparative analysis of Predictability of tentative ARIMA (Autoregressive Integrated Moving Average) models was conducted to determine optimal time-series model for forecasting future price trends. Proposed BIM based time series forecasting model can help to deal with sudden changes in economic conditions by estimating future material prices.

• Atmosphere
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• v.34 no.1
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• pp.35-53
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• 2024

Under the leadership of the National Institute of Meteorological Sciences (NIMS), the first domestic autonomous flight-type weather modification experimental drone for fog and lower-level cloud seeding was developed in 2021. This drone is designed based on a multi-copter configuration with a maximum takeoff weight of approximately 25 kg, enabling the installation of up to four burning flares for seeding materials and facilitating weather observations (temperature, pressure, humidity, and wind) as well as aerosol (PM₁₀, PM_2.5, and PM_1.0) particle measurements. This research aims to introduce the construction of the drone and its recent applications over the past two years, providing insights into the experimental procedures, effectiveness verification, and improvement directions of the weather modification drone-based rain enhancement. In particular, partial confirmation of the experimental effects was obtained through the fog dissipation experiment on December 10, 2021, and the lower-level cloud seeding case study on October 5, 2022. To enhance the scope and rainfall amount of weather modification experiments using drones, various technological approaches, including adjustments to experimental altitude, seeding lines, seeding amount, and verification methods are necessary. Through this research, we aim to propose the development direction for weather modification drone technology, which will serve as foundational technology for practical application of domestic rain enhancement technology.

• Journal of the Korean Institute of Landscape Architecture
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• v.52 no.2
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• pp.51-63
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• 2024

While the government policy to fully adopt BIM in the construction sector is being implemented, the construction and utilization of landscape BIM models are facing challenges due to problems such as limitations in BIM authoring tools, difficulties in modeling natural materials, and a shortage in BIM content including libraries. In particular, plants, fundamental design elements in the field of landscape architecture, must be included in BIM models, yet they are often omitted during the modeling process, or necessary information is not included, which further compromises the quality of the BIM data. This study aimed to contribute to the construction and utilization of landscape BIM models by developing a plant library that complies with BIM standards and is applicable to the landscape industry. The plant library of trees and shrubs was developed in Revit by modeling 3D shapes and collecting attribute items. The geometric information is simplified to express the unique characteristics of each plant species at LOD200, LOD300, and LOD350 levels. The attribute information includes properties on plant species identification, such as species name, specifications, and quantity estimation, as well as ecological attributes and environmental performance information, totaling 24 items. The names of the files were given so that the hierarchy of an object in the landscape field could be revealed and the object name could classify the plant itself. Its usability was examined by building a landscape BIM model of an apartment complex. The result showed that the plant library facilitated the construction process of the landscape BIM model. It was also confirmed that the library was properly operated in the basic utilization of the BIM model, such as 2D documentation, quantity takeoff, and design review. However, the library lacked ground cover, and had limitations in those variables such as the environmental performance of plants because various databases for some materials have not yet been established. Further efforts are needed to develop BIM modeling tools, techniques, and various databases for natural materials. Moreover, entities and systems responsible for creating, managing, distributing, and disseminating BIM libraries must be established.