• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.3
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• pp.269-274
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• 2010

As a preliminary study on a SOFC-GT hybrid system integrated a with coal-gasification system, the influence of the concentrations of $H_2$ and CO in syngas on the performance characteristics of the hybrid system is investigated. It is expected that the differences in the heating values of fuels with different compositions trigger the off-design operation of the gas turbine and result in different performance characteristics of the overall hybrid system. Syngas compositions are found to affect the SOFC performance. Performance of hybrid system with carbon monoxide is poorer than the case with hydrogen. In the case of part-load performance with syngas, performance degradation at part-load operating conditions with hydrogen is more dominant than the case with carbon monoxide.

• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.5
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• pp.96-106
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• 1999

In this study, the advanced shift control algorithm for parallel type hybrid drivetrain system with automated manual transmission(AMT) is proposed. The AMT can be easily realized by mounting the pneumatic actuators and sensors on the clutch and shift levers of the conventional manual transmission. By using the electronic-controlled AMT, engine and induction machine, it is possible to achieve the integrated control of overall system for the efficiency and the performance of the vehicle. Performing the speed control of the induction machine and the engine, the synchronization at gear shifting and the smooth engagement of clutch can be guaranteed. And it enables to reduce the shift shock and shorten the shift time. Hence, it results in the improvement of shift quality and the driving comfort of the vehicle. Dynamometer-based experiments are carried out to prove the validity of the proposed shift control algorithm.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.6
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• pp.893-904
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• 2006

To improve sensitivity of biosensor as yeast two-hybrid detection system for estrogenic activity of suspected chemicals, we tested effects of several combinations of the bait and fish components in the two-hybrid system on Saccharomyces cerevisiae inducted a chromosome-integrated lacZ reporter gene that was under the control of CYC1 promoter and the upstream Gal4p-binding element $UAS_{GAL}$. The bait components that were fused with the Gal4p DNA binding domain are full-length human estrogen receptor ${\alpha}$ and its ligand-binding domain. The fish components that were fused with the Gal4p transcriptional activation domain were nuclear receptor-binding domains of co-activators SRC1 and TIF2. We found that the combination of the full-length human estrogen receptor ${\alpha}$ with the nuclear receptor-binding domain of co-activator SRC1 was most effective for the estrogen-dependent induction of reporter activity among the two-hybrid systems so far reported. The relative strength of transcriptional activation by representative natural and xenobiotic chemicals was well correlated with their estrogenic potency that had been reported with other assay systems.

• Journal of Aerospace System Engineering
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• v.14 no.5
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• pp.42-48
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• 2020

This research illustrates how the hybrid engine system comprising of a two-cycle reciprocal engine with an integrated generator and a battery is prepared for the design process. The purpose of this research is to increase flight endurance taking advantage of the high energy density of hybrid propulsion systems as well as to cope with current environmental issues by reducing fossil fuel. The hybrid system is designed to offer 6 kW power, and the power can be adjusted by controlling the engine's RPM in accordance with load variations. In addition, the battery is adopted to offer extra electric power that this hybrid system cannot cover, and can function as the main power source in limited time in the case of an emergency situation. Besides that, the generator is directly mounted on an engine crank-shaft, and in turn, they can share the same RPM. Thus, it is hypothesized that this integration method can make a compact design possible by reducing space for the installation in the fuselage of UAVs.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.1
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• pp.19-24
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• 2017

Nowadays, based on the advancement of IT techniques, innovative products combining IT techniques to PA system are developing. In this paper, we presented the hybrid mixer controller for digital PA system. We develop the integrated mixer controller which includes the digital mixer composing an existing digital PA system and function of digital integrated controller. Developed integrated mixer controller consists of multichannel mixer function with 16 audio input channels, 8 output channels. And, it has an equalizer for processing digital audio signal, matrix and limiter. Also, the developed controller has some features such as internet connection for controlling of overall PA system and remote monitoring of mixer process condition.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1989.04a
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• pp.71-76
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• 1989

Structural design, generally engineering design, is a complex process combinding design knowledges and analysis techniques. While analysis techniques can be automated in an algorithmic fashion, relatively little work has been done in the area of the design automation. An effect approach method for the automation of the engineering design may be a hybrid system, in which design knowledges, specification requirements and interpretations are represented using an expert system methodology and numerically intensive operations of the design process are implemented using an algorithmic language such as FORTRAN. The purpose of this paper is concentrated on the knowledge of K-CLIPS(KAIST-C Language Integrated Production System) used to design and implement this hybrid system. In K-CLIPS, some representation methods : frame, production rule, fact and user defined function are used to construct the knowledge base. The hierarchical knowledges could be expressed more naturally with a little number of rules than other plain production systems.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.5
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• pp.1023-1028
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• 2012

A MMIC (Monolithic Microwave Integrated Circuit) mixer chip using the Schottky diode of an GaAs p-HEMT process has been developed for the I/Q demodulator of non-contact near field microwave probing system. A single balanced mixer type is adopted to achieve simple structure of the I/Q demodulator. A quadrature hybrid coupler and a quarter wavelength transmission line for 180 degree hybrid are realized with lumped elements of MIM capacitor and spiral inductor to reduce the mixer chip size. According to the on-wafer measurement, this MMIC mixer covers RF and LO frequencies of 1650MHz to 2050MHz with flat conversion loss. The MMIC mixer with miniature size of $2.5mm{\times}1.7mm$ demonstrates conversion loss below 12dB for both variations of RF and LO frequencies, LO-to-IF isolation above 43dB and RF-to-IF isolation above 23dB, respectively.

• Journal of Electrical Engineering and Technology
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• v.8 no.6
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• pp.1571-1578
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• 2013

With the emergence of high-integration array and large area panel process, the need to minimize the generation of particles in the field of semiconductor, LCD and OLED has grown. As an alternative to the conventional roller system, a contactless magnetic conveyor has been proposed to reduce the generation of particles. An EM-PM hybrid which is one of magnetic levitation types is already proposed for the conveyor system. One of problems pointed out with this approach is the vibration caused by the dynamic interaction between conveyor and rail. To reduce the vibration, the introduction of a secondary suspension system which aims to decouple the levitation electromagnet from the main body is proposed. The objective of this study is to develop a dynamic model for the magnetically levitated conveyor, and to investigate the effect of the introduced suspension system. An integrated model of levitation system and rail based on 3D multibody dynamic model is proposed. With the proposed model, the dynamic characteristics of maglev conveyor system are analyzed, and the effect of the secondary suspension and the stiffness and damping are investigated.

• Journal of the Korea Institute of Military Science and Technology
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• v.19 no.5
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• pp.559-566
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• 2016

Cables for Towed Array Sonar System(TASS) were developed. In order to verify the performance of cables, environmental and operational conditions as well as functional requirements were investigated during design stage. Double armored high and low voltage integrated cable for towed body and two kinds of cables, armored and light weight power and optic hybrid cables for towed array sensor system were developed by modeling and simulation. Customized manufacturing process and test method, such as foam extrusion and dynamic fatigue test were applied to this development. In conclusion, underwater towed hybrid cable with high tensile strength and compact structure were developed.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.33 no.5
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• pp.299-310
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• 2009

Fuel cells are expected to be promising future power sources in both aspects of thermal efficiency and environmental friendliness. Accordingly, worldwide research and development efforts have been enormously increasing recently in various applications such as power plants, transportation and portable power sources. Among others, high temperature fuel cells, such as solid oxide fuel cells and molten carbonate fuel cells, are suitable for electric power plants. Moreover, their high operating temperature is quite appropriate to construct further advanced integrated systems. This paper reviews recent literatures on research and development of integrated power generation systems based on high temperature fuel cells. Research and development efforts are summarized in the area of fuel cell/ gas turbine hybrid systems, application of carbon capture technology to fuel cell systems, integration of coal gasification with fuel cells, and the use of alternative fuels.