• Journal of the Korean Society of Combustion
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• v.21 no.4
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• pp.6-15
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• 2016

The oxygen fuel MILD (Moderate or Intense Low-oxygen Dilution) combustion has been considered as one of the promising combustion technology for flame stability, high thermal efficiency, low emissions and improved productivity. In this paper, the effect of oxygen and fuel injection condition on formation of MILD combustion was analyzed using lab scale oxygen fuel MILD combustion furnace. The results show that the flame mode was changed from a diffusion flame mode to a split flame mode via a MILD combustion flame mode with increasing the oxygen flow rate. A high degree of temperature uniformity was achieved using optimized combination of fuel and oxygen injection configuration without the need for external oxygen preheating. In particular, the MILD combustion flame was found to be very stable and constant flame temperature region at 7 KW heating rate and oxygen flow rate 75-80 l/min.

• Culinary science and hospitality research
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• v.9 no.4
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• pp.37-53
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• 2003

The purpose of this study was to find out efficient control plan for productivity increase. To analyze the data, the measure of question a paper was used to 5 a point measure, statistics disposition was used to SPSS, the analyze method was used to frequency analyze, trust degree analyze, difference analyze useful average value, person's correlation analyze, revolution analyze. The results of this study could be explained as follow: First, find out high change separation propensity. Secondly, was subjected important for atmosphere composition and was required strategy consideration for stable job recognition. Third, was operated affirmative to recognition about separation and was increased to job satisfaction according as a colleague relation and team work. Fourth, was increased to comparative separation propensity in case that high job satisfaction. Therefore it is required interesting labor item and treatment development about personal evaluation.

• Journal of the Korean Institute of Intelligent Systems
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• v.7 no.4
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• pp.29-39
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• 1997

A discrete model reference control scheme for a vehicle four wheel steering system(4WS) is proposed and evaluated for a class of discrete time nonlinar dynamics. The schmen employs a neural network to identify the plan systems, wher the neural network estimates the nonlinear dynamics of the plant. The algorithm is proven to be globally stable, with tracking errors converging to the neighborhood of zero. The merits of this scheme is that the global system stability is guaranteed. Whith thd resulting identification model which contains the neural networks, the parameters of controller are adjusted. The proposed scheme is applied to the vehicle active four wheel system and shows the validity and effectiveness through simulation. The three-degree-of freedom vehicle handling model is used to investigate vehicle handing performances. In simulation of the J-turn maneuver, the yaw rate overshoot reduction of a typical mid-size car is improved by 30% compared to a two wheel steering system(2WS) case, resulting that the proposed scheme gives faster yaw rate response andl smaller side slip angle than the 2WS case.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2005.11a
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• pp.375-380
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• 2005

In this paper, We studied an antenna for the wireless home network service. From the structural modification of patch and ground plane, we made a reverse heart shape radiated pattern of antenna which is suited to wireless home network service. As a result, bandwidth between maximum gains is 110 degree, and the difference of downward direction gain from maximum gain have become -3.6dB. Installing the antenna on the ceiling, horizontal plane of the inner home will be formed the uniform electromagnetic environment. Accordingly, stable reception level acquisition and outdoor radiated suppression could be possible.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.496-499
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• 2002

The LQG/LTR controller is a robust and stable control which is systematic method with a view of engineering. And the H$^{\infty}$ scheme is adopted for the design of the controller to reduce the effects of the disturbances. In this paper, LQG/LTR and H$^{\infty}$ Controller Design of Lateral Control System for an Automobile is developed with 3 DOF (degree-of-freedom) model. The performance has been compared for the employed two types of controllers via computed simulations. The results show that the H$^{\infty}$ controller provides more robustness property for the disturbances and lower control input.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.318-321
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• 2002

The LQG/LTR controller is a robust and stable control which is systematic method with a view of engineering. And the H$^{\infty}$ scheme is adopted for the design of the controller to reduce the effects of the disturbances. In this paper, LQG/LTR and H$^{\infty}$ Controller Design of Lateral Control System for an Automobile is developed with 3 DOF (degree-of-freedom) model. The performance has been compared for the employed two types of controllers via computed simulations. The results show that the H$^{\infty}$ controller provides more robustness property for the disturbances and lower control input.

• Journal of Mechanical Science and Technology
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• v.14 no.11
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• pp.1198-1205
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• 2000

A two-degrees-of-freedom servosystem for step-type reference signals has been preposed, in which the integral compensation is effective only when there is a modeling error or a disturbance input. this paper considers robust stability of the servosystem incorporating an observer against both structured and unstructured uncertainties of the plant. A condition is obtained as a linear matrix inequality, under which the servosystem is robustly stable independently of the gain of the integral compensator. This result implies that we can tune the gain to achieve a desirable transient response of the servpsystem preserving robust stability. An example is presented to demonstrate that under the robust stability condition, the transient response can be improved by increasing the gain of the integral compensator.

• Textile Coloration and Finishing
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• v.17 no.4 s.83
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• pp.1-6
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• 2005

We studied the degree of variety of indigo for the electrochemical redox reaction in addition of reducing agent and the electrokinetic parameters. The electrokinetic parameters such asthe number of electron and the exchange rate constant were obtained by cyclic voltammetry. With increasing scan rate, the reduction currents of indigo were increased and the reduction potentials were shifted to the negative direction. As the results, the reduction processes of the indigo were proceeding to totally irreversible and diffusion controlled reaction. Also, exchange rate constant ($k^0$) and diffusion coefficient ($D_0$) of indigo were decreased by increasing concentration of reducing agent. We found that the less concentration, the more easily diffused and electron transferred and the product was more stable.

• Journal of the Korean Graphic Arts Communication Society
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• v.20 no.1
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• pp.65-78
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• 2002

The suspension polymerization of styrene was carried out to obtain the narrow-size distribution of particle by using poly(vinyl alcohol) (PVA) as suspension stabilizer according to the degree of hydrolysis and the molecular weight. The stabilizing properties of suspension are also dependent on the interfacial tension of aqueous solution when PVA is added. When the polymerization process was carried out with low hydrolyzed PVA, it gave single, well-defined particles, while high hydrolyzed PVA gave clusters. The size of particle produced in this study ranged between 5${\mu}{\textrm}{m}$ and 10${\mu}{\textrm}{m}$. The suspending agent, PVA, influences on the drop size and drop stability, When the molecular weight of PVA is increased, the drop size decreases and the drops become more stable toward coalescence. An increase in the PVA concentration decreases the mean drop size and narrows the drop size distribution.

• International Journal of Railway
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• v.9 no.2
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• pp.46-49
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• 2016

In this study a new detection technique based on WAK is introduced that can be used for identifying unstable concrete sleeper installed in ballast by triggering activated wave on the sleeper surface. If a gap exists immediately below the concrete sleeper, static stiffness can be lower than stable case's stiffness. The concrete sleeper is assumed as a single degree of freedom system (SDOF). The static stiffness K can be obtained by iteratively calculated mass (m), stiffness (k) and damping coefficient (c) of SDOF system. Those coefficients are used to specify the ballast condition such as a gap between the sleeper and ballast. Typical test results using a small sleeper model test are summarized and explained for proof of effectiveness of the WAK test for checking unstable condition of the sleeper.