• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.93-97
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• 2011

This paper presents the performance and test results of propulsion system which is met the requirements of urban MAGLEV. The design of propulsion system should be considered the effect of attractive force by the magnetic levitation and train running resistance. In this paper, the tractive and braking thrust are calculated and the train performance is simulated for the service track. Finally the test results of complete car are shown to verify the performance.

• Tribology and Lubricants
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• 제7권2호
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• pp.41-45
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• 1991

An experimental investigation for leakage performance of five anti-swirl self-injection seals was carried out to select an optimum configuration for minimum leakage. Test results show that the self-injection mechanism with a plain seal generally degrades the leakage performance of noncontacting seals; however, through a series of the test program, an optimum anti-swirl self injection seal was selected to obtain a comparable leakage performance with a damper seal. A 12 holes anti-swirl and anti-leakage self-injected. configuration with a labyrinth surface gives minimum leakage among the tested anti-swirl self-injection seals.

• Steel and Composite Structures
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• 제8권6호
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• pp.441-455
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• 2008

This paper presents an effective hysteretic model for the prediction and evaluation of steel reinforced concrete member seismic performance. This model adopts the load-deformation relationship acquired from monotonic load tests and incorporates the double-pivot behavior of composite members subjected to cyclic loads. Deterioration in member stiffness was accounted in the analytical model. The composite member performance assessment control parameters were calibrated from the test results. Comparisons between the cyclic load test results and analytical model validated the proposed method's effectiveness.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -1
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• pp.109-112
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• 2000

In this paper, performance of multicode DS/CDMA packet radio network with adaptive antenna array is analyzed and simulated in a multipath Rayleigh fading channel. The network performance is evaluated in terms of packet throughput. From the simulation results, it is confirmed that the adaptive antenna array is very effective in improving the packet throughput performance of the multicode DS/CDMA packet radio network. The results of this paper can be applied to design of IMT-2000 or future-generation mobile communication systems.

• International Journal of Automotive Technology
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• 제8권4호
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• pp.413-419
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• 2007

Experimental study of additives on the ignition performance of a compression ignition natural gas engine is introduced, followed by results of a simulation of its working mechanism. From the experimental results, it is understood that engine ignition performance can be improved when a certain amount of Di-tertiary-butyl peroxide additive is added. If the mass fraction of Di-tertiary-butyl peroxide additive reaches as high as 14.2%, engine ignition can be realized at ambient temperatures with a glow plug temperature of about $750^{\circ}C$. From the simulation results, we verify that the Di-tertiary-butyl peroxide additive, by cracking its radicals at lower temperature, can accelerate reaction rate. Therefore, the additive is able to improve the ignition performance of natural gas significantly.

• 대한인간공학회:학술대회논문집
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• 대한인간공학회 1995년도 춘계학술대회논문집
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• pp.3-14
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• 1995

To investigate the effect of illumination conditions on visual inspection performance for TV panel glasses, three dependent variables, inspection time, error, and preference , were measured and analyzed through two consecutive experiments. The first experiment for reflection inspection was conducted using two independent variables, position and brightness. The second experiment for transparent inspection was made using two independent variables, height and brightness. The summary of the results of the experiment for reflection inspection are as follows ; The inspection performance of the position right above the subject (Position 1) was the best among the conditions in terms of errors, while the performance of the position slightly in front of and above the subject(Position 2) was the best in terms of inspection times. Inspection time was statistically different according to the brightness conditions specifically at the position in front of the subject(Position 3). The results of the second experimen for transparent inspection are that the inspection performance at medium height (Height 2) was the best among the three conditions in terms of errors while the performance at lower height(Height 3) was the best in subject preference. Based upon both results with respect to actual field conditions, two alternative inspection station designs were proposed for each lighting conditon.

• Journal of Power Electronics
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• 제8권3호
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• pp.268-274
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• 2008

This paper presents a proposed position controller for a vector controlled induction motor. The position controller design depends on the rotational motion equations and a classical speed controller (CSC) performance. The CSC is designed to have the ability to track variable reference inputs and to provide a predefined system performance. Standard position controller in industry is presented to analyze its performance and its drawbacks. Then the proposed position controller is designed, based on the well defined rotational motion equations. The proposed position controller and the CSC are applied to control the position and speed of the vector controlled induction motor with different ratings. Simulation results at different operating conditions are presented to evaluate the proposed controllers' performance. The results show that the CSC can drive the motor with a predefined speed performance and can track a variable reference speed with an approximately zero steady state error. The results also show that the proposed position controller has the ability to effect high-precision positioning in a limited time and to track a variable reference position with a zero steady state error.

• 한국자동차공학회논문집
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• 제16권2호
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• pp.49-57
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• 2008

The performance of crash cushion systems is certified through the full scale crash tests by the standard for installation and maintenance guidelines for roadside safety appurtenance. The impact severities of impacting vehicles in collision with crash cushion systems are rated by indices THIV and PHD. Crash test results are considered to study the performance of three crash cushion systems. In case of the frontal impact or the offset frontal impact, the results show that THIV values of three systems are very close to the threshold limit for the occupant protection. Also, the results show that PHD would be improper for the occupant protection performance index. In order to improve the occupant protection performance of crash cushions, ASI needs to be included in the impact severity index.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2006년 제4회 한국유체공학학술대회 논문집
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• pp.519-522
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• 2006

Experimental and computational studies on an turbopump inducer with and without a bearing strut were performed to evaluate the effects of a strut on the performance of an inducer. Global performance data such as head rise and efficiency, and detailed flow characteristics such as surface static pressures were measured and compared with computational results. Generally a good agreement is observed between experimental and computational results, but some discrepancies are observed due to complex flow features such as backflows at the inlet and strut/inducer interactions. For the flow rates where the backflow region is large, installing a strut enhanced the hydraulic performance of the inducer by diminishing the size of the backflows. The results also show that the strut has negligible effect on the suction performance of the inducer.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 후기학술대회논문집
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• pp.15-16
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• 2005

In this study, the characteristics of NOx reduction by using charge air moisturizer system were evaluated by engine performance simulation in medium speed diesel engines. The results of performance simulation were verified by experimental results of single cylinder medium speed diesel engine equipped with charge air moisturizer system. Performance simulation was carried out to evaluate charge air moisturizer system of turbocharged diesel engine, HYUNDAI HiMSEN 9H25/33 engine. Those results show 50% NOx reduction at dew point $80^{\circ}C$ and charge air pressure 4bar.