• Journal of Biosystems Engineering
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• v.19 no.3
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• pp.175-184
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• 1994

This study was conducted to investigate experimentally the basic characteristics of the torque of the cutterbar driving shaft as the double-knife was used instead of the conventional standard single-knife type. A new design for inclined setting of the cutterbar relative to the direction perpendicular to combine harvester movement was investigated to test a possible reduction of concentrated load caused by the simultaneous cutting of many rows. It was evaluated that the maximum torque and mean total power of the driving shaft due to the cutting resistance of the rice straw were largely depended upon the rotational shaft-speed and straw feeding rate, but were resepectively 1.1~2.3 and 1.15~1.34 times higher compared to those while idling. It was also proved that the inclined setting of the cutterbar could save a considerable amount of energy required for its driving shaft.

• Journal of the Korean Institute of Intelligent Systems
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• v.2 no.3
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• pp.29-39
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• 1992

We investigate a systematic design procedure of automatic rule generation of fuzzy logic based controllers for highly nonlinear dynamic systems such as an engine dynamic modle. By "automatic rule generation" we mean autonomous clustering or collection of such meaningful transitional relations from one conditional subspace to another. During the design procedure, we also consider optimaly control strategies such as minimum squared error, near minimum time, minimum energy or combined performance critiera. Fuzzy feedback control systems designed by our method have the properties of closed-loop stability, robustness under parameter variabitions, and a certain degree of optimality. Most of all, the main advantage of the proposed approach is that reliability can be potentially increased even if a large grain of uncertainty is involved within the control system under consideration. A numerical example is shown in which we apply our strategic fuzzy controller dwsign to a highly nonlinear model of engine idling speed control.d control.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2582-2584
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• 2001

In this paper, this system which constantly control rotation speed of compressor is designed to use in idling state as traffic jam. Also this system is designed to improve reduction of cooling efficiency when sloping and starting a bus. The estimation of designed system in this paper is performed in the laboratory where KS-R-1053 is satisfied. We come to the conclusion that this system is more excellent than the present system in point of cooing ability and response characteristic of controller.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.6
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• pp.259-266
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• 1998

In the SI engine, the improvement of combustion stability is important not only for the fuel consumption rate but also for the emission control at idling of engine. Thus the engine speed fluctuation at idle operation mainly comes from cyclic variation of combustion in the SI engine. In this syudy, the improvement of combustion stability for the SI engine at idle condition by the cooling water temperature, duty ratio of ISC, spark ignition timing as well as the reducement of the harmful exhaust gas emission was discussed.

• International Journal of Automotive Technology
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• v.8 no.2
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• pp.155-163
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• 2007

The control of the fuel to be introduced into the combustion chamber under idling and low-load conditions is known to be a problem in Diesel engines, owing to the relatively small fraction of the full-load fuel needed under light loads. Thus, particular attention should be paid to the behavior of the injector with reference to short injection events. This work presents the results of an experimental campaign carried out with two different types of common rail injectors, a standard injector and a modified one. The latter, coming from a simple modification realized in a standard injector, exhibits linear behavior between injected fuel and solenoid energizing time in the field of short injections. A direct comparison of the two injection behaviors suggests a possible way to better control short or pilot injections.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.2
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• pp.209-214
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• 2009

The simulation software for predicting the performance of a wind turbine generator system (WTGS) is validated using the field measured data obtained from the idling test run of a dual rotor wind turbine recently developed and installed in Korea. Both steady-state and transient responses at low and high wind conditions are compared with the theoretically predicted ones from the simulation software WINSIM.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.584-589
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• 2008

A bi-modal tram has been developing to consist of articulated-two cars propelled by CNG hybrid (series type) in Korea since 2003. All wheels are driven by electrical motors independently, which can eliminate differential gears to reduce turning radius and make low floor to provide the old and the handicapped with easy access. In the bi-modal tram, therefore, reduction gear unit is key technology to make low floor and drive wheels independently. This study was aimed at performance evaluations of the reduction gear unit for the bi-modal tram. Oil leakage, oil temperature, vibration, acoustic noise in idle operations were measured for the reduction gear unit of the bimodal tram.

• International Journal of Air-Conditioning and Refrigeration
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• v.12 no.3
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• pp.141-147
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• 2004

Cogeneration has been widely introduced in many countries for use m industrial, commercial and residential applications. However, there have been few models with an output of less than 100kW. In the present study, a spark ignited gas engine with electric generation output of 10kW was developed for micro cogeneration package. Developed gas engine achieved following performance characteristics such as $26.7\%$ of electric generation efficiency, NOx emission less than 10 ppm at $13\%$ oxygen, 82 dB of noise level, and about 3 seconds of switching time from idling to nominal power.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.8
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• pp.697-703
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• 2003

Cogeneration is the simultaneous generation of heat and electricity in a single unit, and is a highly energy-efficient technology compared to the independent generation of both products. Therefore, cogeneration has been widely introduced in many countries for use in industrial, commercial and residential applications. However, there have been few models with an output of less than 100 kilowatt. In the present study, a spark ignited gas engine with electric generation output of 10 kilowatts was developed for micro cogeneration package. The gas engine shows 26.7% of electric generation efficiency, NOx emission less than 10 ppm at 13% oxygen, 82 dB of Noise level, and about 3 seconds of switching time from idling to nominal power.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.3
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• pp.35-40
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• 2005

In the present study, the influence of operating conditions on fuel economy for hybrid electric vehicle was analyzed. In order to accomplish this, vehicle speed, engine speed, battery current and voltage, SOC (state of charge),motor speed and torque, generator speed and torque, engine coolant temperature etc. were measured in real time. The tests were carried out under different driving cycles which are urban and highway cycles, KOREA CITY cycle and on-road driving, and also under various operating conditions such as different initial SOC, with or without regenerative braking etc.. Generally, conventional gasoline engines show a poor fuel economy at stop and go driving, because braking energy is wasted and the engine is operated in low thermal efficiency regions. However, in case of hybrid vehicles, higher fuel economy can be obtained because of utilizing the maximum thermal efficiency regions of engine, idling stop of engine, and regenerative braking etc..