• Journal of Computational Design and Engineering
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• v.2 no.1
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• pp.16-25
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• 2015

Since construction projects are large and complex, it is especially important to provide concurrent construction process to BIM models with construction automation. In particular, the schematic Quantity Take-Off (QTO) estimation on the BIM models is a strategy, which can be used to assist decision making in just minutes, because 70-80% of construction costs are determined by designers' decisions in the early design stage. This paper suggests a QTO process and a QTO prototype system within the building frame of Open BIM to improve the low reliability of estimation in the early design stage. The research consists of the following four steps: (1) analyzing Level of Detail (LOD) at the early design stage to apply to the QTO process and system, (2) BIM modeling for Open BIM based QTO, (3) checking the quality of the BIM model based on the checklist for applying to QTO and improving constructability, and (4) developing and verifying a QTO prototype system. The proposed QTO system is useful for improving the reliability of schematic estimation through decreasing risk factors and shortening time required.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.5
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• pp.145-152
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• 2019

In this study, rebar QTO(Quantity Take-Off) was quickly produced from the BIM model prepared by Revit in the early design phase, and the available premium rates were quantitatively presented. For this purpose, the amount of rebar calculated using the BuilderHub, which specializes in calculating rebar QTO, was analyzed according to various factors such as member type, rebar diameter, building size, item type, and order length, and the effect of each factor on the rebar QTO was determined. In addition, the BIM model generated on Revit was used to establish parameters and processes required to produce rebar QTO, and proposed a rebar premium rate and a stirrup/hoop premium rate based on the BuilderHub output results. Through this study, it is expected that a rapid and efficient comparative evaluation of rebar QTO will be possible according to various structural design alternatives in the early design phase.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.419-425
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• 2013

Recently AEC industry has required construction automation according to becoming large and complex. Thus BIM-based construction project is increased and used in whole fields of AEC industry. Quantity take-off and estimation fields are important factor for decision-making in conceptual and schematic design stages of construction projects. The purpose of this study improves reliability of the estimation through QTO based on Open BIM. Scope and method to apply QTO is to select conceptual design stage through LoD(Level of Detail) in AEC field and to extract information from BIM model through analysis of IFC structure. This study proceeds three step to make BIM model and check the model quality and calculate QTO. The methodology of QTO using IFC is to verify of result in this study and expects utilizing in design stage of construction projects. The result from this study is expected to decrease the risk factor and time of estimation in the project early phase through improving reliability of schematic estimation.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.289-293
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• 2015

The construction industry has been evolving with the development of information technology. According to this trend, the current industry changes from 2d drawings to Building Information Modeling(BIM). Current studies on the BIM-based estimation have problems such as Quantity Take-Off(QTO) specificity toward a particular software, the uncertainty of the amount in accordance with the model quality. These studies focus on QTO based on BIM rather than schematic estimation. In addition, studies on the connection with the QTO and unit cost for schematic estimation are insufficient. The purpose of this study is to propose schematic estimation process by utilizing construction codes and QTO in architectural object BIM libraries. Construction codes are classified in detail in order to input codes inside each. This study has connected unit cost and construction classification codes that obtain from BIM model. The results of this study will be helpful in decision-making and communication for schematic estimation of the design phase. It will improve the efficiency and reliability problems of existing schematic estimation.

• The Korean Journal of Food And Nutrition
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• v.32 no.6
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• pp.717-729
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• 2019

The chemical informs about 70 individual phenolic compounds were constructed from various lettuce samples based on literature sources and analytical data. A total of 30 phenolic compounds including quercetin 3-O-glucuronide, quercetin 3-O-(6''-O- malonyl) glucoside, cyanidin 3-O-(6''-O-malonyl)glucoside, chlorogenic acid and chicoric acid as major components were identified in 6 lettuce samples from Korea using UPLC-DAD-QToF/MS on the basis of constructed library. Among these, quercetin 3,7-di-O-glucoside(m/z 627 [M+H]⁺), quercetin 3-O-(2''-O-malonyl)glucoside(morkotin C, m/z 551 [M+H]⁺), quercetin 3-O-(6''- O-malonyl)glucoside methyl ester(m/z 565 [M+H]⁺), 5-O-cis-p-coumaroylquinic acid(m/z 339 [M+H]⁺) and 5-O-caffeoylquinic acid methyl ester(m/z 369 [M+H]⁺) were newly confirmed from the lettuce samples. In total content of phenolic compounds, 4 red lettuce samples(2,947.7~7,535.6 mg/100 g, dry weight) showed higher than green lettuce(2,687.3 mg) and head lettuce(320.1 mg).

• Journal of the Computational Structural Engineering Institute of Korea
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• v.35 no.4
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• pp.197-205
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• 2022

In this paper, a retaining wall system, developed using building Information modeling (BIM), is presented. Based on the information from a literature review, elementary technologies for the system were defined and developed. First, for the elementary technology, BIM libraries were constructed using standards and previous study results to achieve versatility and reusability. Second, methods for determining the quantity take-off (QTO) of a retaining wall were reviewed for an earth-work calculating system. Additionally, inverse distance weighting interpolation was used to generate topography. Finally, four formulas for calculating the QTO were proposed and devised for each element. After its development, the BIM system was analyzed and verified through comparison with a two-dimensional drawing-based QTO. The proposed system is deemed to be practical for determining the QTO of retaining walls and earth works. The contributions and limitations of the research are discussed in this paper.

• Journal of the Korean earth science society
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• v.26 no.3
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• pp.199-217
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• 2005

Using monthly total ozone data obtained from a Total Ozone Mapping Spectrometer (TOMS) onboard the Nimbus-7 and Earth Probe satellite, this study examined the trend in the total amount of global ozone during two periods: from 1979-1992 [Early period] and 1997-2002 [Latter period]. The Annual average of total ozone during the Early period was globally reduced by about 10 DU compared to the amount during the Latter, except in some areas between the equator and 20 N. Global trends of total ozone showed a decrease of -6.30 DU/decade during 1979-1992, and an increase of 0.12 DU/decade during 1997-2002. Its enhancement during the Latter period was especially noticeable in tropical areas. The EOF analyses of total ozone from this period indicated signs of temporal/spatial variability, associated with the phenomena of Quasi-Biennial Oscillation (QBO), Quasi-Triennial Oscillation (QTO), El Nino Southern Oscillation (ENSO), and volcanic eruption. Seasonal profiles of tropospheric ozone in the tropics obtained from ozonesondes, showed the spatial pattern of zonal wavenumber one. Overall, this study may be useful in analyzing possible causes in the variations of statospheric and tropospheric ozone.

• Korean Journal of Environmental Agriculture
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• v.37 no.4
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• pp.260-267
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• 2018

BACKGROUND: In this study, shoots of Aralia elata and Kalopanax pictus which belong to the Araliaceae family were analyzed using UPLC-DAD-ESI(+)-QToF/MS to characterize of individual phenolic acids. METHODS AND RESULTS: Total thirteen phenolic acids were identified, and nine hydroxycinnamic acid derivatives have been identified for the first time in shoots of Aralia elata and Kalopanax pictus. For total phenolic acid content (mg/100g dry weight), shoots of Aralia elata and Kalopanax pictus showed 754.8 and 845.3 mg/100g, respectively. 5-O-Caffeoylquinic acid (49%) and 3,5-di-O-caffeoylquinic acid (44%) were found as major phenolic acids in Aralia elata, while 5-O-caffeoylquinic acid (91%) was a major component in Kalopanax pictus. CONCLUSION: On comparing the two plants, it was considered that the biosynthesis of 3,5-di-O-caffeoylquinic acid can be affected by 5-O-caffeoylquinic acid in Aralia elata.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.6
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• pp.567-576
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• 2017

The object of this research is an establishment of BIM-based quantity takeoff(QTO) and cost estimation guidelines for reinforcement concrete structures focused on improvement of field applicability in transition period from 2D drawing-based environment to 3D BIM-based environment. Preliminary studies on existing guidelines and standards for BIM modeling, QTO and cost estimation of reinforcement concrete structures are performed, and then a standardization of BIM-based cost estimation process is proposed through comparative analysis between 2D drawing-based cost estimation process and 3D BIM-based. In addition, modeling, QTO, and cost estimation processes of cost-BIM model for RC structures are conducted. The contributions of this research and the guidelines suggested by this research are 1) lowering barriers to entity to the new BIM-based environment for small size companies, 2) reducing construction cost by a close estimate, 3) establishing the foundation for integrated management of informations through construction project life cycle, 4) and ultimately, developing the BIM ecosystems.

• The Korean Journal of Food And Nutrition
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• v.36 no.6
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• pp.543-550
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• 2023

Mulberry fruit is a superior source of polyphenols, especially anthocyanin, and has a long history of use as an edible fruit and traditional medicine. The anthocyanin composition of mulberry fruit from 15 Korean cultivars was analyzed by ultra-performance liquid chromatography diode array detector with quadrupole time of flight/mass spectrometry (UPLC-DAD-QToF/MS) based on a cyanin internal standard. The four glycosides were identified by comparison with authentic standards and published reports. The major anthocyanin was cyanidin 3-O-glucoside (71.7%), followed by cyanidin 3-O-rutinoside (26.6%). The minor components (total of 1.7%) were pelargonidin 3-O-glucoside and pelargonidin 3-O-rutinoside. The total anthocyanin content (mg/100 g, dry weight) of mulberry fruit varied by cultivar and ranged from 471.5±4.0 (Su Hong) to 4,700.2±54.0 (Gwa Sang2). Among the 15 cultivars examined, Gwa Sang2 showed the highest level of cyanidin 3-O-glucoside (3,133.4±32.6), which was 9-fold higher than that of Su Hong (351.5±3.4). In conclusion, anthocyanin profiles, including pelargonidin 3-O-glucoside and pelargonidin 3-O-rutinoside, were reported for the first time from 15 Korean mulberry fruit cultivars. The results will contribute valuable information on pharmaceutical properties, breeding superior mulberry cultivars, and food industries.