• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1998.04a
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• pp.166-172
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• 1998

In contrast to the conventional intake manifold of steel or aluminum material, the lst natural frequency range of plastic intake manifold becomes very lower to ca. 40Hz. That causes negative effects on the engine control unit installed inside the throttle body. In this paper, support design concepts to increase the natural frequency range larger than max. 200Hz are suggested based on the vibration analysis results using finite-element method. In conclusion, it is shown that the vibration level can be reduced most effectively by the installation of the neck support bracket between the throttle body and the plenum chamber.

• Resources Recycling
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• v.25 no.4
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• pp.11-22
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• 2016

In global automobile industry, the remanufacturing for used products has the merit to be reduced nearly 80 percent of energy consumption and resources of new product. The objective of this paper is the analysis of detailed remanufacturing processes about research object and failure modes of each process of throttle body which is one of automobile parts, to draw a FMEA and determine the degree of seriousness (S), detection (D) and occurrence (O) of many failures. And we compared the current RPN method of being used to calculate values of RPN with three suggested methods. : Summation method, Square root method, Volume method.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.7
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• pp.967-974
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• 2001

Experimental investigations on the flow characteristics of downstream region of a butterfly valve, which is used in SI engine, have been conducted according to Reynolds number and valve angle. Measurement programs of the flowfield using x-type of hotwire anemometry include the mean and fluctuating velocity, turbulnet intensity, shear stress, power spectrum and pressure loss coefficient. Experimental results show that flow characteristics and independent of relatively high Reynolds number; 60,000 and 80,000. It is also seen that streamwise mean velocities have relatively large velocity gradient around the butterfly valve with increasing the valve opening angle and this trend appears even in the far downstream region. The distributions of turbulent intensity and shear stress show irregular behavior regardless of the valve opening angle and those of the case of the valve opening angle of 45°are the largest. The pressure loss coefficient of the body surface of the throttle valve increases mildly with the increase of Reynolds number and increases rapidly with the reduction of the valve opening angle.

• Proceedings of the KSME Conference
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• 2001.11b
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• pp.353-358
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• 2001

Turbo-charging or Super-charging has been used to boost engine power for Gasoline Engine and Diesel Engine came to the world at the beginning of $20^{th}$ century. So far Turbo-Charger has enjoyed a high reputation in the charging filed for its technical advantages such as no demand of operation power from engine and an excellent charging effect in the event of a static operation at mid- and high engine speed. A mechanically driven Super-Charger, however, is now emerging in order to meet demands of the age of speed such as high engine power for a quick change of the driving mode - high engine torque even at low engine speed. Since Super-Charger needs driving power from engine, it cannot improve its relatively higher fuel consumption against that of Turbo-Charger. This negative point is still an obstacle to the wide use of Super-Charger. Super-Charger using Screw-type compressor which has already had a considerable base in air compressor market will fulfill this purpose of improving fuel consumption by minimizing operation power owing to no charging at idling or partially loading driving. This study aims to develop power control concept to achieve this minimization of operation power.

• Journal of the korean Society of Automotive Engineers
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• v.8 no.3
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• pp.16-27
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• 1986

In this study, low emission gasoline engine system is developed utilizing an EGR valve, 3 way catalytic converter and electronic fuel injection system. EGR was controlled by a needle valve and optimized at the engine conditions. Throttle body fuel injection system is used for fueling. When the engine was operated at constant speed by the electronic engine control system with the 3 way catalytic converter, th emissions were reduced by 50 to 90% in volume depending on he engine operating conditions.

• Journal of the korean Society of Automotive Engineers
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• v.9 no.5
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• pp.66-76
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• 1987

The control technique for an electronic engine is studied. For this study an IBM-PC and a throttle body fuel injection system are selected. The computer controls fuel injection, spark timing, exhaust gas recirculation and idle speed. Fuel injection is adjusted either by a feed back signal of a zirconia $O_{2}$ sensor or programmed logic for starting, deceleration, warm ing up and idle modes. When a 3-way catalytic converter is used with the electronic engine control system, CO, THC, and NOx were reduced more than 90% simultaneously.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.696-701
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• 2000

In this study, a mathematical model fur analyzing the shift characteristics is proposed. The proposed model comprises power transmission system and vehicle system, which are coupled. And On-road car test is carried out in order to extract model parameters. Tile model is composed of a detailed powertrain, an engine/AT housing, a simplified suspension system. tires and a vehicle body model. On the test, the vehicle accelerations and pitch ratio are measured by using accelerometers and gyro sensor. The other data, for example speeds, a throttle position and a brake signal, are taken from sensors which already exist in the vehicle. Using natural frequency and characteristic equation, vehicle model parameters are extracted from experimental data.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.4
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• pp.154-162
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• 2004

In this study, a mathematical model for analyzing the shifting transients of the passenger car with an automatic transmission is proposed. The proposed model comprises a power transmission system and a vehicle system, which are coupled. In order to extract the modeling parameters, on-road car test is carried out. The model is composed of a detailed powertrain, an engine/AT housing, a simplified suspension system, tires and a vehicle body model. On the test, the vehicle accelerations and pitch ratio are measured by using accelerometers and a gyro sensor. The speeds, the brake signal, and the throttle position are taken from sensors which already exist in the vehicle. Considering natural ftequencies, which is calculated from the measured accelerations, and the characteristic equation, vehicle model parameters are identified. Dynamic behaviors during upshift or downshift are simulated using the proposed vehicle model. By comparing and analyzing the simulation result and on-road car test data, the vibration of the Engine/AT housing influences the shifting transients. The effect of model parameters are also studied. Among model parameters, the location of engine mountings influences the vibration of the vehicle body.

• Korean Journal of Materials Research
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• v.16 no.11
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• pp.681-686
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• 2006

Plasma nitrocarburising and plasma post oxidation were performed to improve the wear and corrosion resistance of S45C and SCM440 steel by a plasma ion nitriding system. Plasma nitrocarburizing was conducted for 3h at $570^{\circ}C$ in the nitrogen, hydrogen and methane atmosphere to produce the ${\varepsilon}-Fe_{2-3}$(N, C) phase. Plasma post oxidation was performed on the nitrocarburized samples with various oxygen/hydrogen ratio at constant temperature of $500^{\circ}C$ for 1 hour. The very thin magnetite ($Fe_3O_4$) layer $1-2{\mu}m$ in thickness on top of the $15{\sim}25{\mu}m$ ${\varepsilon}-Fe_{2-3}$(N, C) compound layer was obtained by plasma post oxidation. A salt spray test and electrochemical testing revealed that in the tested 5% NaCl solution, the corrosion characteristics of the nitrocarburized compound layer could be further improved by the application of the superficial magnetite layer. Throttle valve shafts were treated under optimum plasma processing conditions. Accelerated life time test results, using throttle body assembled with shaft treated by plasma nitrocarburising and post oxidation, showed that plasma nitrocarburizing and plasma post oxidation processes could be a viable technology in the very near future which can replace $Cr^{6+}$ plating.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.4 s.175
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• pp.926-936
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• 2000

Actual and strict definition of the shift quality for the powertrain system equipped an automatic transmission must be understood through the acceleration change of the vehicle body, which the driver directly feels as a shift shock. For this reason, it is necessary to concurrently analyze the characteristics of the powertrain system and the vehicle body. This paper presents the mathematical model of the vehicle body, which is based on the equivalent lumped system, to append to the developed model of the powertrain system. The concept of tire slip is also introduced for the experimental relationship between tire/road and driving force. Using the developed dynamic simulation programs, shift transients characteristics are analyzed. Theoretical results are compared with experimental ones from real car tests in equal conditions in order to prove the validity of presented model. In these tests, the system to measure the vehicle acceleration is used with various speeds and engine throttle sensors. It is expected that the presented modeling techniques can provide good predictions of the vehicle driving comfortability.