• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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• pp.19-22
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• 2003

This study is carried out (1) checking the development of compressive strength of high flowing concrete at early age, changing water-binder ratio, curing temperature, and type of aggregate, and (2) suggesting basic date that helping cost and schedule plan in future construction. As the result of this study, we find that high curing temperature is effective for the development of compressive strength of concrete at early age on the condition of each water-binder ratio, and after making the compressive prediction formula related to the curing temperature by maturity, the result of the formular is similar to the temperature-compressive strength-age measured data

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.417-422
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• 2005

The appropriate ventilation system in vehicular tunnel should be the most economical solution with regard to both construction and maintenance. The damages on tunnel lining was affected by formula of ventilation system in long vehicular tunnel. In this study, carbonation, one of main experimental items in precision safety diagnosis, was analyzed by contouring damage area with ventilation system. Considerations of carbonation were also given to the design and maintenance which manage the long-term safety in tunnel.

• 전기의세계
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• 제28권3호
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• pp.72-77
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• 1979

The object of this paper is to try to develope Tulular Liner Induction Motor which consists of primary stator that generates traveling magnetic field from the three-phase winding of formed-wound concentric coil, and try to identify the characteristics of starting force. To indentify the theoretical starting force formular we have quoted the conventional Maxwell's basic equation and Poisson's equation which are used in the general machines thereby having obtained the formular of the current with in the conductor and of the air gap magnetic field respectively. General starting force formular is acquired by applying the formular of the current and magnetic field which was theoretically derived above. To this theoretically starting force formula various constants and the values of magnetic flux density resulting from the experimental motor are applied to present theoretically calculated values. Comparing these theoretically caculated values experimentally weighed values, we have proved the validity of theoretical research.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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• pp.413-414
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• 2010

기존 연구에 따르면 강도 증가에 따라 설계기준에서 제시하는 콘크리트의 탄성계수가 실제 탄성계수를 과대평가하고 있다고 언급하고 있으나 2007년에 콘크리트구조설계기준이 개정되었기 때문에 개정된 탄성계수 산정식에 대한 확인이 필요한 실정이다. 본 연구에서는 고강도 콘크리트의 실험을 통해 탄성계수를 제안하였으며 제안식과 2003 콘크리트구조설계기준 및 2007 콘크리트구조설계기준의 탄성계수를 비교분석하였다.

• 제어로봇시스템학회논문지
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• 제10권4호
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• pp.304-311
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• 2004

In this paper we present a technique of discrete-time sliding mode controller design for assigning eigenvalues of sliding mode and determining a convergence rate to sliding surface. First the sliding mode coefficient is designed via Ackermann s formula. Then a linear controller is designed to enforce sliding mode such that the resulting closed loop yields the desired eigenvalues. As we use a linear control instead of nonlinear control, chattering is nearly eliminated. Simulation and experimental results are included to show the effectiveness of the proposed method for Laser Marking System.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.2031-2036
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• 2003

High-pressurized jet is widely using in industrial works. however, few papers studied on the performances or characteristics on that kind of nozzles. And in this study, some flow characteristics with the variation of nozzle aspect ratios such as mean velocity distributions, momentum variations along the center line have been experimentally investigated. As the results, some semi-empirical correlations of profiles of pressure and mean velocity distributions, momentum conservations with the nozzle aspect ratios are formulated. It is expected that these empirical formula can be applied for the random estimations of nozzle performances.

• 한국기계가공학회지
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• 제11권3호
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• pp.98-103
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• 2012

One of the problems in the grinding process using the machining center(MC) with a small diametric wheels is machining error due to decrease of the quill diameter. In this thesis, side-cut grinding is performed with a vitrified bonded CBN wheel on the machining center to establish the basis of the grinding using MC. The grinding force and machining error are investigated experimentally for the change of the machining condition. It is possible to estimate the machining performance by the ratio of the setting depth of cut and actual depth of cut. In addition, the relation between normal grinding force and machining error is presented by the experimental formula.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회/대한산업공학회 2003년도 춘계공동학술대회
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• pp.668-673
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• 2003

Line Capacity is a criteria for transport capacity and is used to evaluate railroad investment alternatives or to decide train frequency when establish transportation plan. There are two methodologies to increase transport capacity of railway. One is to invest railroad equipment or vehicles, and the other is to improve operation efficiency through optimization. Such all efforts are intended to increase transport capacity by improving line capacity. So far, this criteria is calculated statical and experimental numerical formula. But, line capacity has special attribute that changes dynamically according to operational conditions, so there is a need of new line capacity estimation system. In this paper, we present a new estimation method of line capacity based on the probability simulation, and apply to normal railline section and special structured railine section.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.790-793
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• 2001

The characteristics of smart skin for wireless LAN system under compression load are investigated. The smart skin structure is composed of 3 layers of face material and 2 layers of core material. Theoretical formula for determining buckling load is derived by Rayleigh-Ritz method and compared with experimental result. The maximum length of specimen that buckling does not occur is determined by assuming that the compression load is sustained by only face material. In the experiment, if buckling occurs obviously then it follows the theoretical result well. In the process of buckling, the load supporting capability and the antenna property such as radiation pattern and reflection coefficient were examined.

• Journal of Mechanical Science and Technology
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• 제15권2호
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• pp.239-247
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• 2001

Measured radiative heat fluxes on the furnace exit plane of a heavy duty power boiler of steam output 1650 T/h are discussed. A high-ash pulverized bituminous coal was used. Such measurements are necessary to improve heat fluxes inside a steam boiler furnace was manufactured. An extra small heat radiation sensor was placed in the water cooled head of the probe. The sensor had no direct contact with furnace gases and measured only the radiant energy. There was no exposure to convective heat transfer. With the radiometric probe, one can obtain a spherical indicatrix of radiation intensity as well as hemispherical radiative heat flux incident on any surface passing through a measuring point inside the furnace. Thus, the quantity of radiation energy, passing through the furnace exit plane, to the convective heating surfaces and the quantity of radiation energy going in the opposite direction were measured. A formula for relative radiative heat flux on the furnace exit plane has been proposed.