• Journal of Korean Institute of Industrial Engineers
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• v.22 no.3
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• pp.399-412
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• 1996

With respect to the effects of types of knowledge on human diagnostic performance, the results of several experiments claimed that training with procedural knowledge is more effective than training with principle knowledge. However, more useful results would be attained by investigating when and how the principles of system dynamics is valuable for diagnosis. Accordingly, we conducted an experiment to reevaluate the value of principle knowledge in two problem situations. A simulator system, named DLD, to diagnose an electronic device was created. It is a context-free digital logic circuit which includes forty-one gates of three basic types. The experiment investigated the effects of principle knowledge over common procedural knowledge. The experimental results showed that the effects of principle knowledge is dependent on the complexity of diagnostic situations. This adds up on experimental evidence against the presumed ineffectiveness of principle knowledge and forward reasoning in fault diagnosis. The results also suggest the source of the usefulness of principle knowledge.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2522-2524
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• 2000

In this paper, a controller design for ironless linear synchronous motor is proposed. The designed controller is mainly composed of speed and current control, which are carried out by the high-speed digital signal processor(DSP). In addition the PWM inverter is controlled by space voltage PWM method. This system is implemented using by 32-bit DSP(TMS32OC31), a high-integrated logic device(EPM940), and IPM(Intelligent Power Module) for compact and powerful system design. The experimental results show the effective performance of controller for careless linear synchronous motor.

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.1143-1145
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• 2000

In this paper, it presents the design and implementation of a Microstep control IC using Programmable Logic Device(PLD). A Microstep driver is implemented with a 5-phase hybrid stepping motor, which has a Pentagon winding, power MOSFETs, and some devices to improve the system characteristics. The Microstep driving method is used for high performance motion control, low vibration and low noise in motor control system. The improvement of the electrical and mechanical driving characteristic of a step motor is achieved by applying microstep driver.

• Proceedings of the KIEE Conference
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• 2006.10a
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• pp.224-226
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• 2006

In this paper, we have studied for analysis of the partial discharge(PD) signal in power transmission line. The PD signal has estimated as detected signal accumulation of a PRPDA method by using Labview, and analyzed with neuro-fuzzy algorithm. With practical PD logic implementation of theoretical detected system and hardware implementation, the device for Hipotronics Company's 22.9kV or 154kV setup has generated and then has applied with 18kV,20kV with 1:1 time probe. It's also used the LDPE O.27mmt (scratch error O.05mmt) to sample for making PD. Our new class of PD detected algorithm has also compared with previous PRPDA or Fuzzy algorithm, which has diagnose more conveniently by adding numerical values.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.4 no.3
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• pp.316-321
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• 2004

In this paper, we have developed a new mounting head system for flip chip. The proposed head system consists of a macro/micro positioning actuator for stable force control. The macro actuator provides the system with a gross motion while the micro device yields fine tuned motion to reduce the harmful impact force that occurs between very small sized electronic parts and the surface of a PCB(printed circuit board). In order to show the effectiveness of the proposed macro/micro chip mounting system, we compared the proposed system with the conventional chip mounting head equipped with a macro actuator only. A series of experiments were executed under the mounting conditions such as various access velocities and PCB stiffness. As a result of this study, a satisfactory voice coil actuator as the micro actuator has been developed, and its performance meet well the specifications desired for the design of the chip mounting head system and show good correspondence between theoretical analysis and experimental results.

• Proceedings of the IEEK Conference
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• 2001.06e
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• pp.135-138
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• 2001

This paper presents micro step driving method using VHDL(Very high speed integrated circuit Hardware Description Language) which can configure CPLD(Complex Programmable Logic Device). Using VHDL which can do abstractive programming is similar to high level language. The whole block divided into five parts with freq. divide part, saw-tooth wave generation part, sine-cosine wave generation part, comparative part, out part. In the result of this study, peripheral circuits are to be simple and using LPM(Library of Parameterized Modules) is more easily to configure circuit. It is easy to verify and implement by using VHDL. To subdivide one natural step, we confirm that using micro step driver is expected that the rotor motion is stepless very smooth.

• Journal of Magnetics
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• v.14 no.1
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• pp.23-26
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• 2009

Spin injection from a ferromagnet into an n-doped $In_{0.53}Ga_{0.47}As$ channel was electrically detected by a ferromagnetic detector. At T = 20 K, using non-local and local spin-valve measurements, a non-local signal of $2\;{\mu}V$ and a local spin valve signal of 0.041% were observed when the bias current was 1 mA. The band calculation and Shubnikov-de Haas oscillation measurement in a bulk channel showed that the gate controlled spin-orbit interaction was not large enough to control the spin precession but it could be a worthy candidate for a logic device using spin accumulation and diffusion.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.453-456
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• 1999

The Si-SiO$_2$interface trap and nitride bulk trap distribution of SONOSFET(polysilicon-oxide-nitride-oxide-semiconductor)NVSM(nonvolatile semiconductor memory) cell were investigated by single charge pumping method. The used device was fabricated by 0.35 7m standard logic fabrication including the ONO cell process. This ONO dielectric thickness is tunnel oxide 24 $\AA$, nitride 74 $\AA$, blocking oxide 25 $\AA$, respectively. Keeping the pulse base level in accumulation and pulsing the surface into inversion with increasing amplitudes, the charge pumping current flow from the single junction. Using the obtained I$_{cp}$-V$_{h}$ curve, the local V$_{t}$ distribution, doping concentration, lateral interface trap distribution and lateral memory trap distribution were extracted. The maximum N$_{it}$($\chi$) of 1.62$\times$10$^{19}$ /cm$^2$were determined.mined.d.

• The Transactions of the Korea Information Processing Society
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• v.5 no.3
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• pp.811-823
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• 1998

캐쉬 메모리 시스템의 성능 측정 방법으로 이제까지 널리 사용되고 있는 방법이 트레이스 구동 시뮬레이션이다. 트레이스 구동 시뮬레이션의 정확성은 사용하는 트레이스의 크기, 포함된 정보의 종류 등에 의해서 크게 영향을 받는다. 이에 따라 보다 정확한 트레이스를 생성하기 위해 많은 방법들이 제안되었으며 그 중 하드웨어 모니터링 기법에 의해서 얻어진 트레이스는 응용 프로그램의 메모리 참조에 대한 정보뿐만 아니라, 문맥교환이나 시스템 프로그램의 메모리 참조에 대한 정보, 메모리 참조가 발생한 시간 정보 등을 가진다는 장점을 갖는다. 그러나 하드웨어 모니터링 시스템은 트레이스를 생성하기 위한 시스템에 따라서 설계가 변화되어야 하는 단점이 있다. 본 논문에서는 이러한 하드웨어 모니터링 시스템의 단점을 완화하기 위해서 EPLD(Erasable Programmable Logic Device)를 사용하여 트레이스 생성 시스템을 구성하여, 보다 간단한 수정으로 여러 시스템에서 트레이스 생성이 가능한 하드웨어 시스템을 설계하였다. 또한 제작된 트레이스 생성 시스템은 66Mhz의 고속 버스 시스템에서 동작할 수 있는 특징을 갖는다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.11a
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• pp.418-420
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• 1997

We synthesized the polymer that can have function group and improvement of mechnical strength and then confirmed the possibility of molecular device made by LB method. In this paper, the $\pi$-A isotherm has been investigated as to the kinds and various concentrations of the metal ions complexed with imidazole group. The experimental results for the electrical properties of MIM fabricated has been obtained as following. There is no change in limiting area as to the kinds of the metal ions, also the shift of conductivity as to the metal ions couldn't be observed, which was 10$\^$-14/[S/cm]. There are some changes in limiting area as to the concentration of the metal ions, the conductivity shift was increased with the occupied molecular area.