• Proceedings of the Korea Concrete Institute Conference
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• 1995.10a
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• pp.119-123
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• 1995

This paper presents an accelerated-curing method by the war water method and discusses how these methods can be adapted for regular quality control and quality assurance of concret. Accelerated strength test data can be used for estimating the furture stength, e.g. the 28-day strength. An accelerated-curing method to predict the 28-day strength of concrete from 1-day warm water-cured test results was evaluated in the laboratory and the field. For these evaluations test are performed for 1845 standard specimens from 123 different batches of concrete. The results of this study the equation applicable universally with resonable accuracy are presented for estimating the potential strength of concrete by the warm water-curing method.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1733-1734
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• 2008

We develope a riding robot system named as "RideBot" for health-care and entertainments. An algorithm for estimating riding position and volition is proposed by using bio-signals. We analyze the riding position and volition in real-horse riding environments and build up the database. With this database and sensor informations, standard positions are made. For the volition estimation, we use the acceleration and deceleration sensor information and bridle information for direction change. We propose a hybrid control algorithm in which discrete-state and continuous-state controls are combined. The efficiency of the proposed algorithm is evaluated thru various experiments.

• Korean Journal of Veterinary Research
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• v.53 no.2
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• pp.73-76
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• 2013

The aim of this study was to produce a simple and inexpensive technique for estimating the obturator foramen area (OFA) from young calves based on the hypothesis that OFA can be extrapolated from simple linear measurements. Three linear measurements - dorsoventral height, craneocaudal width and total perimeter of obturator foramen - were obtained from 55 bovine hemicoxae. Different algorithms for determining OFA were then produced with a regression analysis (curve fitting) and statistical analysis software. The most simple equation was OFA ($mm^2$) = [3,150.538 + ($36.111^*CW$)] - [147,856.033/DH] (where CW = craneocaudal width and DH = dorsoventral height, both in mm), representing a good nonlinear model with a standard deviation of error for the estimate of 232.44 and a coefficient of multiple determination of 0.846. This formula may be helpful as a repeatable and easily performed estimation of the obturator foramen area in young bovines. The area of the obturator foramen magnum can thus be estimated using this regression formula.

• Journal of the military operations research society of Korea
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• v.31 no.2
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• pp.45-59
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• 2005

As more advanced and complicated equipments are introduced, effective operation and maintenance, along with acquisition of the equipments, commands more significance lately. In order to perform effective depot maintenance, the Republic of Korea Army is continually developing the concept, cycle and method for operating the depot maintenance. Not only the high-cost testing and maintenance equipments but the highly developed maintenance technologies are required for the depot maintenance of the latest weapon system. In order to have the depot maintenance capability, this paper provides the standard and procedure for estimating the development cost of the depot maintenance elements to be utilized in the depot maintenance elements development project.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.488-493
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• 2013

Accurate initial cost estimates are essential to effective management of construction projects where many decisions are made in the course of project management by referencing the estimates. In practice, the initial estimates are frequently derived from historical actual cost data, for which standard distribution-based techniques are widely applied in the construction industry to account for risk associated with the estimates. This approach assumes the same probability distribution of estimate errors for any selected estimates. This assumption, however, is not always satisfied. In order to account for the probabilistic nature of estimate errors, an alternative method for measuring the risk associated with a selected initial estimate is developed by applying the Bayesian probability approach. An application example include demonstrates how the method is implemented. A hypothesis test is conducted to reveal the robustness of the Bayesian probability model. The method is envisioned to effectively complement cost estimating methods that are currently in use by providing benefits as follows: (1) it effectively accounts for the probabilistic nature of errors in estimates; (2) it is easy to implement by using historical estimates and actual costs that are readily available in most construction companies; and (3) it minimizes subjective judgment by using quantitative data only.

• Journal of the Korean Society of Safety
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• v.22 no.5
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• pp.33-40
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• 2007

Standard safety management costs can not be applied to each site with same rate, it is very difficult, because it depends on the experience, work method, work kind, work progress schedule, and hazard level of each construction company. Therefore, this study is to find out hazard level of each work kinds through questionnaire and interview and investigate analyze the status which standard safety management costs have been used. Also, this study is to show reasonable rates of standard safety management costs in construction industry and to set up countermeasures against those problem after reviewing its status in korea with in Japan and Europe. This study is to investigate eleven project kinds of domestic system, first, and to investigate eleven items of apartment bldg, office. Also this study is to investigate and analyze performed costs of presently processing worker finished work so that it shows a new reasonable rate against standard safety management costs in construction industry, in order to make basical data and material to be systemized.

• Journal of the Korean Society of Safety
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• v.27 no.5
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• pp.185-189
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• 2012

While there is no standards on slip risk for contaminants on surface, glycerol is described in standard contaminant for measuring coefficient of friction(COF) and slip resistance such as ISO 13287. But that is just used to measure the slip resistance of surface materials and shoes not to evaluate the contaminant materials. Therefore the objective of this study was to find out the relationship between standard contaminant and the contaminants used usually at the workplaces. For this, some measurement criteria were acquired from the analysis based on biomechanics and kinetics of human gait during slips. The slip resistance according to viscosity of the contaminants was measured applying the criteria and slip probability was determined by the gait analysis. Some factors which should be considered when measuring the slip resistance were identified. The velocity, acceleration, contact time and contact pressure should be 1 m/sec, 10 $m/sec^2$, 350 kPa and less than 0.5sec respectively. The variation of viscosity according to temperature for working oils was different from that of standard contaminant. The static coefficient of friction (SCOF) of working oils was almost 0.5 times as large as the SCOF of standard contaminant. So it was assumed to be difficult to compare the contaminants at the workplaces with the glycerol as a standard contaminant for estimating the slip risk.

• Journal of the Korean Society of Safety
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• v.21 no.5 s.77
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• pp.53-59
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• 2006

Standard safety management costs can not be applied to each site with same rate, it is very difficult, because it depends on the experience, work method, work kind, work progress schedule, and hazard level of each construction company. Therefore, this study is to find out hazard level of each work kinds through questionnaire and interview and investigate analyze the status which standard safety management costs have been used. Also, this study is to show reasonable rates of standard safety management costs in construction industry and to set up countermeasures against those problem after reviewing its status in korea with in Japan and Europe. The domestic system of standard safety management costs is not considered in the foreign country, while only related subjective items have been investigated and evaluated for this study. This study is to investigate eleven project kinds of domestic system, first, and to investigate eleven items of apartment bldg, office, civil work such as bridge, tunnel, dam, plant etc, secondly. Additionally, three items of gymnasium, railway, particular steel tower are investigated in this study. Also this study is to investigate and analyze performed costs of presently processing worker finished work so that it shows a new reasonable rate against standard safety management costs in construction industry, in order to make basial data and material to be systemized.

• Journal of Korean Society on Water Environment
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• v.35 no.6
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• pp.481-496
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• 2019

The Ministry of Environment has measured streamflow at eight-day intervals for the estimation of standard flow of the Total Maximum Daily Loads (TMDL) system. This study identified the availability of the partially measured the eight-day interval data for estimating standard flow and found the optimal extension techniques of standard flow. The study area was selected for the Nakbon-A watershed in the Nakdong River, and four streamflow record extension techniques of standard flow were considered: extension, percentile, drainagearea, and regional regression methods. The flow duration curve (FDC) using the eight-day interval streamflow data indicated very high Nash and Sutcliffe Efficiency (NSE) values above 90 % from FDC-II to FDC-VII compared to FDC-VIII, the standard FDC. This result demonstrates that FDC using daily data of three-six cumulative years could represent standard FDC fairly well. For the streamflow record extension techniques of standard flow, the percentile method was selected as the optimal alternative, showing the minimal difference from FDC-VIII. These results validate the availability of the eight-day interval streamflow data in the standard flow estimation and the application of extension techniques. It seems that these results could reduce the uncertainty of partially measured streamflow data for water quantity and quality management.

• Korean Journal of Construction Engineering and Management
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• v.23 no.5
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• pp.65-76
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• 2022

The New Excellent Technology (NET) designation system, introduced in 1989 for the purpose of promoting the development of domestic construction technology and enhancing national competitiveness, reviews the statement of construction cost of new technologies. And the cost reduction effect such as design, construction, and maintenance cost and the effect of reducing the construction duration are evaluated as an evaluation criteria of economic feasibility. However, in this evaluation process, differences of opinion between the institution of construction cost estimating standard management and the new technology developer about unique technologies frequently occur. In addition it is difficult to objectively compare the construction duration with existing similar technologies because there is no information on productivity as the current cost estimating standards for new technologies only present the required amount per unit quantity. In this study, the current state of cost estimating criteria review procedure, evaluation criteria, and cost estimating standards establishment method were analyzed when screening for the designation of a new construction technologies, and compared with overseas cost estimating standards, measures to improve the cost estimating standards of current construction new technologies were suggested. Through the improved cost estimating standards of this study, it is expected that cost information on new technologies will be provided to clients in more detail than the current ones, and the availability and applicability of new construction technologies would be improved by simplifying the construction cost calculation process more.