• 한국대기환경학회지
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• 제15권3호
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• pp.281-289
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• 1999

A new E-$\varepsilon$ turbulence numerical model is proposed for analysing the turbulent air flow field within are urban street canyon. In this model the equations of eddy viscosity and energy dissipation ae reformed by considering the Kolmogorov time scale and streamline curvature effect. Application results of the new E-$\varepsilon$ model have been compared with those of standard E-$\varepsilon$ model and Yang and Shih's one, which are commonly used ones in engineering fields, and with field experiment results of DePaul and Sheih. The new model appears to be generally superior to other both models in the prediction of an air flow field within street canyon.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 A
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• pp.389-391
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• 1999

Recently, the application of the linear machine for industrial field is remarkable increased, especially for the gantry machine. machine tool system and CNC. In these application fields. high precise position control performance is essentially required in both the steady and transient state. And linear machine is necessary for high-precision processing and manipulation when relatively high forces are involved. This paper presents the new unified PID position control algorithm which have rare sensitivity to disturbance, which the gain adjusting process is simple. Also this paper investigates the use of the New Unified PID control to design for high stiffness. Through the experimental results, it is shown that the proposed algorithm has high dynamic characteristic for the linear machine application field nevertheless of its simple structure.

• 대한공간정보학회지
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• 제17권2호
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• pp.19-26
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• 2009

국토지반정보 DB구축을 위한 국토해양부의 사업은 2007년도의 경우 건설현장에서 자동으로 지반조사성과가 전산화되도록 하는 '지반조사성과전산화및활용에관한지침' 제정 및 시범적용사업이 추진되었으며, 2008년도부터 안정화된 법제도를 기반으로 국토해양부 전 소속기관, 산하기관, 지자체를 대상으로한 본격적인 사업을 추진하였다. 따라서, 본사업으로 추진된 2008년도 사업에서는 국토지반정보 DB구축과 함께 DB활용을 위하여 지반정보시스템을 활용한 이용자 및 지반정보 유통자료를 다운로드하여 직접 활용한 사용자를 대상으로 지반정보 활용도 분석 및 활용향상을 위한 방안을 수립하였다. 본 논문에서는 국토지반정보 DB활용사례조사를 통한 활용도 분석내용과 향후 활용방안에 대한 연구결과를 제시하였다. 활용도 분석결과, 분야별 분석에서는 공사계획 및 예비조사분야에서의 활용도가 39%로 가장 높았으며, 활용성효과별 분석에서는 업무 효율성 증대가 25%로 가장 높게 나왔다. 그리고, 활용분야별 분석에서는 건축 및 토목분야가 95%로 지반정보 활용도가 가장 높았다.

• KSTLE International Journal
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• 제6권1호
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• pp.8-12
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• 2005

The electrorheological properties pertaining to the electrorheological (ER) bebaviour of chitin and chitosan suspensions in silicone oil were investigated. Chitosan suspension showed a typical ER response (Bingham flow behavior) upon application of an electric field, while chitin suspension acted as a Newtonian fluid. The difference in behaior results from the difference in the conductivity of the chitin and chitosan particles, even though they have a similar chemical structure. The shear stress for the chitosan suspension exhibited a linear dependence on the volume fraction of particles and a 1.18 power of the electric field. The experimental results for the chitosan suspension correlated with the conduction model for ER response.

• Structural Engineering and Mechanics
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• 제78권1호
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• pp.1-13
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• 2021

In this study, the porothermoelastic problem with the effect of the magnetic field and initial stress was investigated. We applied normal mode analysis to solve the resulting non-dimensional coupled equations. Numerical results for the displacements, temperature distribution, pore pressure, stresses, induced electric field and induced magnetic field distributions are presented graphically and discussed. The medium deformed because of thermal shock and due to the application of the magnetic field, there result an induced magnetic and an induced electric field in the medium. Numerical analyses are given graphically on the square (2D) and cubic (3D) domains to illustrate the effects of the porosity parameter, magnetic field and initial stress parameter on the physical variables.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 가을 학술발표회 논문집(II)
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• pp.1091-1094
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• 2000

An experimental study is carried out to estimate the way of applying the granulated blast furnace slag[GBFS] to the lean concrete subbase of concrete pavement. According to the test results, this application seems promising. For this application, mixing percent of GBFS ranging from 30 to 45 is recommendable at this stage. Expected benefits using GGBFS in the field of concrete pavement include reduced shrinkage crack, reduced pavement thickness, and extended service life.

• Structural Engineering and Mechanics
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• 제8권1호
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• pp.19-26
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• 1999

Superior performance of field consistent eight-node hexahedron element in static bending problems has already been demonstrated in literature. In this paper, its performance in free vibration is investigated. Free vibration frequencies of typical test problems have been computed using this element. The results establish its superior performance in free vibration, particularly in thin plate application and near incompressibility regimes, demonstrating that shear locking, Poisson's stiffening and volumetric locking have been eliminated.

• 전기학회논문지P
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• 제58권1호
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• pp.85-89
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• 2009

We investigated the quench characteristics in accordance with increase of turns number of trigger coil and shunt resistance of matrix-type superconducting fault current limiter (SFCL) with $2{\times}3$ array. The matrix-type SFCL consists of the trigger part to apply magnetic field and the current-limiting part to limit fault current. The fault current limiting characteristics according to the increase of magnetic field and applied voltage were nearly same. This is because the application of magnetic field hasn't an affect on total impedance of the SFCL. When turns number of a reactor increased, the voltage difference between two superconducting units in the current-limiting part according was decreased. The resistance difference generated in two superconducting units was also decreased. Therefore, we confirmed that the differences of the critical behaviors between superconducting units were reduced by application of magnetic field. By this results, we could decide the optimum turns number of reactor to apply magnetic field.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.141-142
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• 2008

According as USN's application field is magnified, various results are appearing. Efforts to apply this results in life are progressing. In car field, is used in control that level of significance is less. In home network, is used in a household electric appli-ance control and electric lamp control, security etc.. In factory, is used in process control, and is used in various application because is involved with RFID leader recently. In this paper, patient's status monitoring, USN use wish to. Because USN can utilize existent network, it is system that can transmit various data as that change passed information.Wish to send information that get in health-care board. Information that can get in health-care board is blood pressure, blood sugar, stroke, SPO2, ECG, the activity amount, position. Also, wish to forecast use possibility to involved various service, silver industry with database.

• 한국전기전자재료학회논문지
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• 제36권6호
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• pp.598-602
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• 2023

With the purpose of instilling an awareness of the safety of users of electrical equipment and inducing voluntary facility improvement through the safety rating system for general low voltage electrical equipment, simulation and field application of the safety rating of general low voltage electrical equipment were conducted. For the introduction and application of the safety rating system for general low-voltage electrical equipment, data related to domestic safety was investigated and analyzed, cases of introduction in other fields were reviewed, and for design, the 4M risk assessment method of the Korea Occupational Safety and Health Agency and the cases of safety index development in Korea were analyzed and standardized. Safety rating system simulations were conducted for general low-voltage electrical equipment, and problem improvement measures were prepared by analyzing the results through on-site verification and simulation applied to the initial design. Design standards for the introduction of the safety rating system for general low-voltage electrical equipment were prepared, and 394 youth training facilities were applied to the field to see if the design standards were practically applicable to the field. With the application of the safety rating system for low-voltage electrical equipment for general use, youth training facilities that had been classified as 'appropriate' were able to induce an upgrade to a higher level through voluntary facility improvement according to the application of grades (A to E). As a result of inducing voluntary repair projects based on the results of the 1st and 2nd inspection of youth training facilities, it was confirmed that 86 facilities received grade A, 225 facilities received grade B, and only 311 facilities received grade A to B out of a total of 394 facilities, and there was no grade E.