• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.74.1-74
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• 2001

In this paper, we deal with an allocation model of vertical type container yard for minimizing the total ATC work time and the equivalence of ATC work´s load in each block on automated container terminal. Firstly, a layout of automated container terminal yard is shown. The characteristic of equipment which is operated in the terminal and basic assumption are given. Next, an allocation model which concerns with minimizing the total work time and the equivalence of work´s load is proposed for the effectiveness of ATC work in automated container terminal. Also, a weight values on critical function are suggested to adjust the critical values by evaluating the obtained allocation plan. To find the solution of allocation model in given terminal yard situation, a GA is applied, where the real information of container is used ...

• Journal of Advanced Marine Engineering and Technology
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• v.27 no.5
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• pp.624-632
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• 2003

In the gasoline engine industry. there has been a trend towards the development of high performance engines with improved fuel efficiency, reduced weight and smaller sizes. These trends help to solved engine problems related to thermal load and abnormal combustion. In order to investigate these Problems, a thin film-type probe for instantaneously measuring temperatures has been suggested. A method for manufacturing such a probe was established in this study. The instantaneous surface temperature of a constant volume combustion chamber was measured by this probe and the heat flux was obtained through Fourier analysis. A peak instantaneous temperature was obtained after 55∼60 ms from ignition and the temperature increased according to an equivalence ratio and varied differently according to the position of the probe. Total heat loss during combustion period was affected by the equivalence ratio and differed widely in accordance to the position of the probe.

• Journal of the Korean Society of Combustion
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• v.21 no.3
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• pp.7-15
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• 2016

The fuel in conventional liquid fuel combustor is atomized by spray method for high efficiency and low emissions. To improve the overall fuel efficiency and lower pollutant emissions in liquid fuel combustion systems, the effective spatial and temporal separation of droplet evaporation from normal spray process is needed. In this paper, the recuperation of high temperature burnt gas for fuel evaporation was proposed to develop a cylindrical premixed combustor. The recuperation process using U shaped tube is effective to evaporate the liquid fuel. The results show that the flame mode is changed into red radiation flame, blue flame and lift off flame with decreasing equivalence ratio as gas fuel combustion mode. In particular, the blue flame is found to be very stable at heating load 9.2 kW and equivalence ratio 0.731. NOx was measured blow 105 ppm ($O_2$ zero base) from equivalence ratio 0.705 to 0.835. CO which is a very important emission index in liquid fuel combustor was observed below 5 ppm ($O_2$ zero base) under the same equivalence region.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.7
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• pp.350-359
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• 2017

Premixed burner is a very strong candidate in household condensing gas boiler burner system because it has low CO and NOx emission with high thermal efficiency. The objective of this study was to determine combustion characteristics of cylindrical premixed burner using different baffle plate and flame holes. Results showed that cylindrical premixed flame mode could be changed into lift-off flame, blue flame, red flame, and green flame with increasing equivalence ratio. In particular, blue flame was found to be very stable at heating load of 8,82~35,280 kcal/h. NOx emission was under 26 ppm between 0.775 to 0.813 of equivalence ratio. CO emission was under 58 ppm under the same equivalence ratio. Thermal efficiency, a very important index in condensing gas boiler, was found to be above 90.13% under the same equivalence region.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.419-420
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• 2012

• Journal of Korean Institute of Industrial Engineers
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• v.21 no.4
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• pp.629-638
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• 1995

It is shown that the reliability function of an n-component parallel system is equivalent to that of n-component stand-by system if we increase the exponential failure rates of the parallel system's components in proportion to the increasing load per surviving component.

• Transactions of the Korean hydrogen and new energy society
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• v.23 no.2
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• pp.183-190
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• 2012

The research shows the experiment results according to the combustion characteristics and configuration of the linear generator of powerpack for the generating power applying the 2-stroke compact linear engine. The powerpack used in this paper consists of 2-stroke linear engine, linear generator and air compressor parts. For identifying the combustion characteristics and generating power of linear engine, some parameters were varied sucha as electric load, fuel input calorie, spark timing delay and equivalence ratio. Also generating power was confirmed at each operation conditions, when the air gap length of linear generator part was changed as each 1.0 mm and 2.0 mm. During the all operations, intake air was inputted under the wide open throttle. Mass flow rate of air and fuel was changed using mass flow controller, after these were premixed by premixture device, and then premixed gas was supplied directly into each cylinder. As a result, piston frequency and combustion characteristics were different at each conditions according to parameters affecting the combustion such as fuel input calorie, resistive load, spark timing delay and equivalence ratio. Consequently, these had an effect on generating power.

• Journal of Advanced Marine Engineering and Technology
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• v.28 no.3
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• pp.475-481
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• 2004

Recently it is strongly required on lower fuel consumption. lower exhaust emission, higher engine performance. and social demands in a spark ignition gasoline engine. In this study. the experimental engine used at test. it has been modified the lean burn gasoline engine. and used the programmable engine management system, and connected the controller circuit which is designed for the engine control. At the parametric study of the engine experiment, it has been controlled with fuel injection, ignition timing. swirl mode, equivalence ratio engine dynamometer load and speed as the important factors governing the engine performance adaptively. It has been found the combustion characteristics to overcome the hysteresis phenomena between normal and lean air-fuel mixing ranges. by mean of the look-up table set up the mapping values. at the optimum conditions during the engine operation. As the result, it is found that the strength of the swirl flow with the variation of engine speed and load is effective on combustion characteristics to reduce the bandwidth of the hysteresis regions. The results show that mass fraction burned and heat release rate pattern with crank angle are reduced much rather, and brake specific fuel consumption is also reduced simultaneously.

• Transactions of the Korean Society of Automotive Engineers
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• v.1 no.2
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• pp.27-33
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• 1993

Using the solenoid driven gas injection valve, Hydrogen fuel supply system was made. It was attached to a single cylinder research engine and intake port injection type hydrogen fueled S.I. engine was constructed. Engine performance, emission characteristics, and abnormal combustion were studied through the engine test performed with the variations of fuel-air equivalence ratio and spark timing. Compared with gasoline, hydrogen burns so fast that cylinder peak pressure and temperature are higher and NO is emitted more at full load condition. IN the case of intake port injection type engine, COVimep becomes lower due to the well-mixing of air and fuel, and engine output is lower owing to the low volumetric efficiency. As fuel-air equivalence ratio goes up, the combustion speed increases, and COVimep decreases. NO emission peaks slightly lean of stoichiometric. As spark timing advances and fuel-air equivalence ratio goes up, the cylinder peak pressure and temperature become higher, so abnormal combustions take place easily.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.10a
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• pp.487-492
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• 1997

Two-way concrete slab is often modeled as an orthotropic plate. In the modeling, flexural rigidities of the slab which depend upon the re-bar quantity have to be taken into account. Elastic equivalence technique in which the equilibrium and compatibility of the cross-section of slab satisfied is utilized to determine th flexural rigidities. In the analysis Navier's method is applied on the concrete slab with all edges simply supported under inform lateral load. In addition to the analysis using orthotropic plate theory, finite element method is also adopted to suggest the finite element modeling and to investigate the applicability of the method. Results obtained by both methods were compared and it is observed that the difference of the results was increased as the ratio of re-bar quantity increased.