• Journal of Electrical Engineering and Technology
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• v.8 no.4
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• pp.930-937
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• 2013

In this paper, a motor control algorithm for performing a mode change without an integrated starter generator (ISG) is suggested for the automatic transmission-based hybrid electric vehicle (HEV). Dynamic models of the HEV powertrains such as engine, motor, and mode clutch are derived for the transient state during the mode change, and the HEV performance simulator is developed. Using the HEV performance bench tester, the characteristics of the mode clutch torque are measured and the motor torque required for the mode clutch synchronization is determined. Based on the dynamic models and the mode clutch torque, a motor torque control algorithm is presented for mode changes, and motor control without the ISG is investigated and compared with the existing ISG control.

• Journal of the Korea Society of Computer and Information
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• v.13 no.3
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• pp.45-55
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• 2008

Due to the increasing complexity of embedded system design, automatic code generation of embedded software and hardware-software co-design methodologies are gaining great interest from industries and academia. Such an automatic design methodologies are always demanding a formal system specification languages for defining designer's idea clearly and precisely. In this paper, we propose automatic embedded C code generation from SDL (Specification and Description Language, ITU-T recommended the SDL as a standard system description language) with considering a real-time uC/OS-II operating system. Our automatic embedded C code generator is expected to provide a fast specification, verification and performance evaluation platform for embedded software designs.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.3
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• pp.28-34
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• 2010

In this paper, the transceiver for RFID reader using 13.56MHz as a carrier frequency and meeting International Standard ISO 14443 type A, 14443 type B and 15693 is presented. The receiver is composed of envelope detector, VGA(Variable Gain Amplifier), filter, comparator to recovery the received signal. The proposed automatic reference voltage generator, positive peak detector, negative peak detector, and data slicer circuit can adjust the decision level of reference voltage over the received signal amplitudes. The transmitter is designed to drive high voltage and current to meet the 15693 specification. By using inductor loading circuit which can swing more than power supply and drive large current even under low impedance condition, it can control modulation rate from 30 percent to 5 percent, 100 perccnt and drive the output currents from 5 mA to 240 mA depending on standards. The 13.56 MHZ RFID reader is implemented in $0.18\;{\mu}m$ CM08 technology at 3.3V single supply. The chip area excluding pads is $1.5mm\;{\times}\;1.5mm$.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.35 no.12
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• pp.560-566
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• 1986

In the design of an RF discharge system, the electrical equivalence of the gas discharge must be known. With this knowledge, one can design a suitable matching network for a maximum power transfer from the RF generator into the discharge. For this purpose, an experiment has been conducted in which the electrical impedance (conductance and capacitance) was determined as a function of power. In parallel with this, a detailed theoretical analysis has been done and the results are in accord with those of our experiment. Design equations are also given for a simple matching network, and a design example is presented to demonstrate its application. During the actual operation of an RF discharge system, however, it has been often observed that the reflected power tends to vary in small values due to the changes in the impedance of the system. This problem can be relieved by adding an automatic impedance matching circuit to the system and this paper presents such an automatic impedance matching network.

• Journal of Advanced Marine Engineering and Technology
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• v.24 no.3
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• pp.106-112
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• 2000

Since the oil crisis, we have been concerned about the energy saving techniques of electric generating systems. As a part of the effort to save energy, automatic electric load sharing device was developed. Usually, ship's electric generating system consists of two or three sets of generator. And, electric generating system is operated as single or parallel operation mode according to the demanded electric power. Therefore, it is important to investigate generators operating mode for the supply of required electric power in the ship in order to decrease the operating cost. So, this paper suggests the method to solve the optimal electric load distribution problem by dynamic programming. And, this thesis indicates that the proposed method is superior to the lagrange multiplier's method in obtaining optimal load distribution solution in the ship's electric generating system.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.2 no.4
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• pp.61-66
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• 2003

An excellent mesh construction is of Importance in yielding good results of finite element analysis. The new mesh generation algorithm, which offsets boundaries inward, was developed on the basis of a looping method. An user interface technique and automatic splitting lines which both divide a given domain into subdomains manually or automatically, were used. In addition, the separation method has advantages to prevent the large scale of element size and to control numbers of nodes and elements. This new mesh generation algorithm was proved in practice.

• Magazine of the Korean Society of Agricultural Engineers
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• v.43 no.6
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• pp.187-196
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• 2001

In this study, by using the natural language processing of the field of artificial intelligence, automated index was performed. And then, the Natural Language Processing Interface for knowledge representation(NALPI) has been developed. Furthermore, the DEsign KnOwledge DataBase(DEKODB) has been also developed, which is designed to interlock the knowledge base. The DEKODB processes both the documented design-data, like a concrete standard specification, and the design knowledge from an expert. The DEKODB is also simulates the design space of structures accordance with the production rule, and thus it is determined that DEKODB can be used as a engine to retrieve new knowledge and to implement knowledge base that is necessary to the development of automatic design system. The application field of the system, which has been developed in this study, can be expanded by supplement of the design knowledge at DEKODB and developing dictionaries for foreign languages. Furthermore, the perfect automation at the data accumulation and development of the automatic rule generator should benefit the unified design automation.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.28A no.9
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• pp.761-773
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• 1991

In this paper, an algorithm for automatic schematic generation which creates schematic diagram from netlist are proposed. The important objectives on schematic generation are readability and clarity of resulting schematics. Each stage of generation should aim at enhancing these objectives. For this reason, schematic generation problem is divided into 5 subproblems` preprocessing, logical placement, pin assignment and improvement of placement, global routing, and detailed routing. The algorithm is implemented in C language, and it generates schematics from the results of logic synthesis in order to make it east for designers to understand the design and reflect their knowledge into design.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.05a
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• pp.209-214
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• 2005

In this paper, finite element simulation of three-dimensional bulk metal forming processes is performed by an automated adaptive tetrahedral mesh generation scheme. A dynamic data exchange scheme is employed between tetrahedral mesh generator and forging simulator to minimize user intervention. Both number of elements and density distributions are controlled by the octree technique. The presented approach is applied to automatic forging simulation in order to evaluate the efficiency of the developed schemes and the simulation results are compared with $DEFORM^{TM}$.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.34 no.1
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• pp.29-37
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• 1985

During Severe emergencies which result in the case of outage of large generator units, an automatic underfrequency protection scheme can prevent the system frequency from decaying and improve the system stability. This paper presents methods and results of a study on the optimum load shedding scheme which covering as follows. 1) Detail representation of governor model 2) Determination of optimum load shedding amount 3) Selection of action time settings of UFR 4) Comparsson of load shedding programs By this study, the optimum system operating method was recommended for reliable operation of power system.