• Architectural research
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• v.15 no.2
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• pp.103-109
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• 2013

Various types of building information should be linked to 3D model objects for their effective use by stakeholders. Because Building Information Modeling (BIM) based on 3D is used by different stakeholders, the created BIM need standard guidelines for each purpose, as, for example, for quantity take-off. Thus, this study was conducted to propose guidelines for BIM modeling for quantity take-off in the framework, especially, in the concrete and form. The proposed guidelines adopted each element of the BIM model based on an analysis of the problem of the general BIM model. Moreover, the usability and accuracy of the reinforced structure modeling guidelines were verified by comparing the quantity of the commercial estimation software and the modeling quantity using the proposed modeling guidelines.

• Journal of the Korean Operations Research and Management Science Society
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• v.27 no.2
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• pp.81-96
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• 2002

Telecommunication services are distinctive in that their adoptions are influenced by network effect resulting in 'the late take-off phenomenon' and the 'critical mass' problem. In this paper we examined, so called, 'the late take-off phenomenon' in the diffusion process of telecommunication services. We compared the parameters of the diffusion process of consumer durables with those of fax services in the US and Korea. By analyzing the parameters of a new diffusion model based on the threshold model proposed by Markus, we found that 'the late take-off phenomenon' resulted from the low heterogeneity of the threshold distribution for the potential adopters. A simulation approach was proposed for the theoretical implication of the 'critical mass' problem in the start-up telecommunications services.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.20 no.1
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• pp.94-102
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• 2012

The aim of this paper is to research the change in the turbulent flow and the AOA occurred by $60^{\circ}$ crosswind to the direction of runway through the three-dimensional numerical analysis and to predict the take-off and landing flight stability. As a result, the maximum amplitude of AOA variation on runway reached $4.88^{\circ}$ within 7 second because of the wake formed by the constructions in the vicinity of the airport, and the overall effects appeared as an irregular aperiodic forms. Additionally, it was observed that the layout and shape of the buildings effected on the strength of turbulence directly, and the rapid flow generated between the buildings changed into stronger wake and eventually expected that the flow raises serious take-off and landing flight instability.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.92-93
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• 2019

Estimates based on BIM makes it possible to perform from quantity take-off to construction cost estimates by using model, which is made in the phase of design and construction. As the BIM models are made up of the units of element, there an advantage of the automative quantity take-off, if the correction or change of element occurs. Work items, not included in the elements of the BIM model, are excepted from bill of quantity. Level of detail(LoD) of the BIM model can be improved for detailed estimates, but an excessive modeling for estimates is inefficient. This study presents the measure for selection and quantity take-off of work items, those are not expressed in the BIM model. The proposed method avoids the creation of excessive BIM Models and enables quantity take-off in conjunction with the element.

• Proceedings of the Korean Association for Survey Research Conference
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• 2003.06a
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• pp.29-33
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• 2003

In business survey. cut off sampling is usual. The contribution from cut off part of the population is at least small in comparison with the remaining population. In this study. the population have been separated as three stratum, cut-off. take-some, take-all, and we will estimate cut-off part.

• Korean Journal of Applied Biomechanics
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• v.21 no.5
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• pp.585-593
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• 2011

The purpose of this study was to analyze, from a kinematical point of view, the high jump techniques of three women's high jump winners at the IAAF World Championships, Daegu 2011. The trends for the techniques of the world's top high jumpers were examined, with a view toward adapting these techniques to the physical characteristics of Korean women's high jumpers. It was valuable that Di Martino, who was the shortest in height, was able to win a medal by using a single arm swing take-off technique, along with a half flexed leading leg swing to attain a deep arch and clear the bar. This showed that the world's top athletes used jumping techniques with no decrease in the run-up velocity at the take-off. Furthermore, It appeared that the knee joint angle at take-off had a direct effect on the body position at take-off (H1).

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.2
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• pp.277-283
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• 2016

Recently, the interests in three-dimensional design and BIM(Building Information Modeling) are increasing in civil engineering sector and the researches about three-dimensional design and quantity take-off methods for civil engineering structures have been conducted. However, these studies are just carried out the 3D design and quantity calculation of civil structures on the road or railway such as bridges and tunnels. The study on the quantity take-off methods and the evaluation of calculated results on the earth works should be performed in more detail. Based on these backgrounds in mind, the study was conducted the three-dimensional road design and evaluated the quantity take-off results on the earth works using 3D calculation method(average end area method, prismoidal method and composit method). The calculated quantity from composit method showed about 5% error of measuring efficiency than the average end area method, and when reporting the quantity calculation of earth works, it is necessary to specify the calculation method using quantity take-off of earth works.

• Korean Journal of Applied Biomechanics
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• v.14 no.1
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• pp.83-98
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• 2004

The purpose of this study was to determine the kinematic variables of the hurdling for a korea record holder (A) and a national hurdle representative (B). after the kinematic variables such the distance and the distance and height of C.G, the velocity and the angle were analyzed about the hurdling. The results were summarized as follows; 1. In terms of the distance and the height of C.G, subject A showed long in horizontal distance from C.G to the take-off phase, but showed short in the landing phase. Subject B showed short in horizontal distance from C.G to the take-off phase, and showed long in the landing phase. 2. In terms of the velocity of C.G, Subject A showed fast C.G velocity in horizontal direction to the braking phase, Subject A and B showed slower C.G velority in the landing phase, but Subject A showed height C.G velocity in vertical direction to the to the take-off, the landing, and propulsion phase 3. In terms of the angle of C.G and lean of C.G to front at the braking and the take-off phase. Subject A kept the less angle in the maximum trunk lean to front at the flight phase as comparison with Subject B. 4. In terms of the velocity of the knee and the ankle joint. Subject A showed fast in the resultant velocity of the left ankle joint the take-off phase, but showed slow in the left knee joint. Subject B showed fast in the resultant velocity of the left knee joint the take-off phase, but showed slow in the right knee and the right ankle joint.

• Journal of the Society of Naval Architects of Korea
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• v.61 no.5
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• pp.400-410
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• 2024

The Republic of Korea Navy is reviewing the development of a ship capable of operating STOVL (Short Take-Off and Vertical Landing) aircraft. However, the Navy has no experience in operating or building such ships, so engineering means are needed to review the design and confirm the operating concept at the concept and basic design stages. In this paper, the authors introduce the results of developing a STOVL aircraft take-off and landing simulation system that reflects the ship's seaworthiness characteristics and major design dimensions based on engineering-based modeling and simulation technology in response to the Navy's needs. The simulation system was developed in which the engineering characteristics of the ship were estimated based on the basic design, and the motion characteristics of the aircraft were implemented by developing equations of motion for a general STOVL. The system was developed to simulate naval aircraft's take-off and landing process and deck movement situation and to confirm the ship operation scenario. By using this simulation system, the Navy will be able to examine not only the ship's structural characteristics at the basic design stage but also the basic conditions for special operational requirements such as take-off and landing.

• The Korean Journal of Applied Statistics
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• v.27 no.3
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• pp.501-512
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• 2014

Modified cut-off sampling is widely used for highly skewed data. A serious drawback of modified cut-off sampling is the difficulty of adjustment of non-response in take-all stratum. Therefore, solutions of the problems of non-response in take-all stratum have been studied in various ways such as substitute of samples, imputation or re-weight method. In this paper, a new cut-off point based on minimizing MSE being used in exponential and power functions is suggested and it can be reduced the number of take-all stratum. We also investigate another cut-off point determination method with underlying distributions such as truncated log-normal and truncated gamma distributions. Finally we suggest the optimal cut-off point which has a minimum of take-all stratum size among suggested methods. Simulation studies are performed and Labor Survey data and simulated data are used for the case study.