• Journal of Korean Society of Industrial and Systems Engineering
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• v.32 no.1
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• pp.44-51
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• 2009

A bonded warehouse is the warehouse located in bonded area. It functions not only as a general warehouse but also as a place for managing the work related to import and export bonded goods. As a general warehouse, it uses the rack system to store the goods and the folk lift truck to move the unitized goods. The operation of the storing system closely related to the efficiency of space uses in a warehouse and vehicle working. Thus, vehicle performance measured in distance units in the ware-house could be used as one of the key performance measure in warehouse system. This paper focuses on the operation efficiency of the bonded warehouse which uses rack system for the storing and the folk lift truck for moving goods. The method of load allocation for balancing the rack uses and vehicle operation for maximizing efficiency are the specific concerns in this paper. The simulation study is conducted to find a policy for efficient vehicle operation based on balanced rack utilization, and the favorable result for the system operation would lead the usable proposal in vehicle operation.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.516-519
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• 1997

In this paper, the control of the temperature for the vehicle air conditioner is implemented with the fuzzy controller using a micro controller. The linguistic control rules of the fuzzy controller are separated into two out variables(multi input multi output ; MIMO) : one is those for the blower motor, and the other is those for air mix door. The error in fuzzy controller, the input variable is defined as difference between the reference temperature and the actual temperature in the cabin room. The fuzzy control rules are established from the human operator experience, and based engineering knowledge about the process. The method of the center of gravity is utilized for the defuzzification.

• Journal of Applied Reliability
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• v.5 no.1
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• pp.149-165
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• 2005

Air spring system was accepted for railway vehicle secondary suspension to reduce and absorb the vibration and noise. The low natural frequency ensures a comfortable ride and an invariably good stiffness. In this paper, the characteristics and durability test was conducted in laboratory by using servo-hydraulic fatigue testing system to reliability evaluation of air spring for electric railway vehicle. The experimental results show that the characteristics and durability of domestic development productions are obtained the good results. And to guarantee the adaption of air spring, the ride comfort and air pressure variation were measured in train test on subway line.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.52 no.11
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• pp.535-540
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• 2003

Since axial flux motor has an advantage over more conventional radial flux type motor such as high power density, it can be used as a power train for hybrid electric vehicle and electric vehicle. Also operating range can be extended and efficiency can be improved by changing air gap. Optimal operating air gap is estimated based on the measured efficiency at different air gap. Motor model is developed based on estimated optimal air gap and efficiency. Motor/controller performance is analyzed through simulation. Possible application area of axial flux motor was explored through simulation.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.6
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• pp.942-948
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• 2011

The performance of a supercharger for vehicle using solar cell attached on the exterior of a car, an auxiliary battery, and an air compressor was evaluated in this study. This supercharger is composed of a solar cell of 40W, a battery of 60 Ah, an air compressor of 17 A, 8 $kgf/cm^2$ and an air tank of 8L. It takes about 6 days to charge the battery with the solar cell and the high pressure air of 8L can be supplied about 70 times to engine intake with this battery. The intake pressure increased by about 20~40% with this supercharger. The vehicle power and accelerating performance are enhanced by 87% and 50% each in the low speed range. But the performance improved little in the high speed range because of the rather constant flow rate of air supplied by this type of supercharger.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.1
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• pp.16-22
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• 2007

Fuel efficiency is one of the major issues in regard to energy and environment. As customers desire more comfortable vehicles, increase of accessory traction force is necessary. Air conditioning system (ACS) consumes the biggest traction force among accessories, especially during summer. This means ACS is the primary object deteriorating fuel economy among accessories. Since direct measurement of traction force and fuel consumption in practical vehicle is difficult, comparison analysis is taken between vehicle with and without ACS working. For this comparison, real time measurements are carried out to know ACS traction force and fuel consumption. As a result of the comparison, a vehicle without ACS operation was 15.92% superior to a vehicle with ACS operating. It could be used as a fundamental material for improvement ACS for better fuel efficiency.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.11
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• pp.1047-1051
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• 2013

A modern combat vehicle needs to have a separate air-conditioning unit, although new combat systems tend to employ an integrated heating, cooling, and ventilating system. In this study, we investigated an air conditioning unit for an armored combat wheeled vehicle as a special use and military specification and performed a case study of a unique military combat vehicle. By using Fluent software, we tried to determine a suitable air ducting method and its location in the armored combat vehicle. The results show that an air-conditioning unit is one of the best solutions for wheeled vehicles that are not equipped with a cooling unit for their crews, and it can be applied to similar types of armored vehicles.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.7
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• pp.705-710
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• 2012

In this study, an experiment on an air conditioning test bench was performed to verify the possibility of fuel economy simulation for the SC03 mode, North America fuel economy certification mode with a/c on condition, one of the vehicle fuel economy evaluation modes. The air conditioning test bench used in this study had each chamber simulating the actual vehicle air conditioning system and the controlling temperature, humidity, and air flow velocity to reproduce environmental conditions. Reliable results were obtained about the compressor RPM and inlet air velocity in front of the condenser corresponding to vehicle speed and air velocity in front of the vehicle, respectively, in the simulation of the SC03 mode, previously performed in CWT, in an air conditioning test bench. It was also discovered that there was a distinct difference in the fuel economy depending on the difference in the compressor displacement in the simulation test of the SC03 mode in the air conditioning test bench under various displacement conditions of the compressor.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.690-699
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• 2008

In this paper a conventional approach for design and analysis of subsonic air vehicle is used. First of all subsonic aerodynamic coefficients are calculated using Computational Fluid Dynamics(CFD) tools and then wind-tunnel model was developed that integrates vehicle components including control surfaces and initial data is validated as well as refined to enhance aerodynamic efficiency of control surfaces. Experimental data and limited computational fluid dynamics solutions were obtained over a Mach number range of 0.5 to 0.8. The experimental data show the component build-up effects and the aerodynamic characteristics of the fully integrated configurations, including control surface effectiveness. The aerodynamic performance of the fully integrated configurations is comparable to previously tested subsonic vehicle models. Mathematical model of the dynamic equations in 6-Degree of Freedom(DOF) is then simulated using MATLAB/SIMULINK to simulate trajectory of vehicle. Effect of altitude on range, Mach no and stability is also shown. The approach presented here is suitable enough for preliminary conceptual design. The trajectory evaluation method devised accurately predicted the performance for the air vehicle studied. Formulas for the aerodynamic coefficients for this model are constructed to include the effects of several different aspects contributing to the aerodynamic performance of the vehicle. Characteristic parameter values of the model are compared with those found in a different set of similar air vehicle simulations. We execute a set of example problems which solve the dynamic equations to find the aircraft trajectory given specified control inputs.

• Journal of ILASS-Korea
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• v.19 no.2
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• pp.64-68
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• 2014

A driving vehicle performance which is driven by FTP-75 mode was simulated by computer. Throttle valve position, engine speed, air mass flow rate, fuel consumption et al. were computer simulated. A set of engine part load performance data, automatic transmission shift map and vehicle specifications were used for the computer simulation. Throttle valve position, engine speed, air mass flow rate et al. measured for evaluating the computer simulation results by driving the vehicle with FTP-75 mode on a chassis dynamometer. GT-Power$^{(R)}$ software was used for the computer simulation of the driving vehicle performance. Experimental fuel consumption rate was measured by using an ECU HILS fuel injection system. The experimental data and simulation results were compared. The computer simulation of the driving vehicle performance predicts the measured data well comparatively.