• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2002.10a
• /
• pp.459-462
• /
• 2002

This paper presents the development or a keypad test system for the improvement or the working environment and productivity improvement using the microprocessor PIC16F877 Chip. In order to detect the fault of keypad products, the design of hardware and software is performed in this system. All controls of the system is implemented by the 8 bit one chip micro-controller PIC. This keypad test system can also recognizes the work process, the work result and the fault position of the keypad which is made by the method of a flexible printed circuit (FPC) and construct the database about test results using personal computer. The experimental results show the effective performance of the keypad test system.

• Proceedings of the KIEE Conference
• /
• 2005.10a
• /
• pp.118-121
• /
• 2005

In this paper, it has been proposed the simultaneous controller of electronic ballast and PFC(power factor corrector) for fluorescent lamp by one chip micro-controller. Boost DC-DC converter is adopted for PFC, and half bridge inverter for electronic ballast. It controls, simultaneously and independently, the boost DC-DC converter and the half bridge inverter. As electronic ballast and PFC are controlled by one chip micro-controller, it is possible to achieve the cheaper controller for fluorescent lamp. Experimental result has shown the feasibility of the proposed simultaneous controller of PFC and electronic ballast.

• Proceedings of the KIPE Conference
• /
• 1998.11a
• /
• pp.5-8
• /
• 1998

The adaptation to vector control theory is so generalized that it is widely used for implementing the high-performance of AC machine. Nowadays, One-Chip microprocessors or DSP chips are being well-used to implement Vector Control algorithm. DSP Chip have less flexibility for memory decoding and I/O rather than One-Chip microprocessor so that is requires more additional circuit and high cost. And the past One-Chip micro processors have difficult of implementation the complex algorithm because of small memory capacity and low arithmetic performance. Therefore we implemented the vector control algorithm of PMSM(Permanent Magnetic Synchronous Motors) using 80296SA form intel , which have many features as 6M memory space, 500MHz clock frequency, including memory decoding circuit and general I/O, Special I/O(EPA, Interrupt controller, Timer/Count, PWM generator) which is proper controller for the complex algorithm or operation program requiring so much memory capacity, So in this paper we fully digitized the vector control of PMSM included SVPWM Voltage controller using the intel 80296SA

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2006.05a
• /
• pp.71-73
• /
• 2006

This research aims to develop a multiple channel electrochemical DNA chip using micro- fabrication technology. At first, we fabricated a high integrated type DNA chip array by lithography technology. Several probe DNAs consisting of thiol group at their 5-end were immobilized on the gold electrodes. Then target DNAs were hybridized by an electrical force. Redox peak of cyclic-voltammogram showed a difference between target DNA and mismatched DNA in the anodic peak current. Therefore. it is able to detect a various genes electrochemically after immobilization of a various probe DNA and hybridization of label-free DNA on the electrodes simultaneously. It suggested that this DNA chip could recognize the sequence specific genes.

• Journal of Sensor Science and Technology
• /
• v.14 no.5
• /
• pp.308-312
• /
• 2005

We present a microfluidic chip designed for the detection of antibody by using quantum dots fluorescence and a microbead-based assay. A custom designed PDMS microfluidic chip with multi-layer channel is utilized for capturing microbeads; antibody injection into each micro-well; QD injection; and fluorescence detection. The experiment using the fabricated microfluidic chip has been performed on solutions with various concentrations of antibody and has shown correlated fluorescent intensities.

• Journal of the Semiconductor & Display Technology
• /
• v.22 no.4
• /
• pp.38-47
• /
• 2023

Three dimensional (3D) packaging is a next-generation packaging technology that vertically stacks chips such as memory devices. The necessity of 3D packaging is driven by the increasing demand for smaller, high-performance electronic devices (HPC, AI, HBM). Also, it facilitates innovative applications across another fields. With growing demand for high-performance devices, companies of semiconductor fields are trying advanced packaging techniques, including 2.5D and 3D packaging, MR-MUF, and hybrid bonding. These techniques are essential for achieving higher chip integration, but challenges in mass production and fine-pitch bump connectivity persist. Advanced bonding technologies are important for advancing the semiconductor industry. In this review, it was described 3D packaging technologies for chip integration including mass reflow, thermal compression bonding, laser assisted bonding, hybrid bonding.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2006.11a
• /
• pp.247-248
• /
• 2006

Carbon nitride films were evaluated that they had many advantages for miniature micro-humidity-sensors using the standard CMOS technology humidity sensing properties and CV characteristics of the carbon nitride films have been investigated for fabricating one chip HUSFET(Humidity Sensitive Field Effect Transistor) humidity sensors Carbon nitride films were deposited on silicon substrate with meshed electrodes by reactive RF magnetron sputtering system. The capacitor-type humidity sensor revealed good humidity-impedance characteristics with a wide range of relative humidity changes, decreasing $254k{\Omega}$ to $16k{\Omega}$ according to increase of relative humidity between 5% ~ 95% and the films were very stable on the Si wafer. These results reveal that $CN_x$ thin films can be used for Si based or HUSFET structure one chip micro-humidity sensors.

• Journal of the Korean Society for Precision Engineering
• /
• v.15 no.5
• /
• pp.65-71
• /
• 1998

This paper presents in-process compensation methodology to eliminate cutter runout and improve machined surface quality. The cutter runout compensation system consists of the micro-positioning mechanism with the PZT (piezo-electric translator) which is embeded in the sliding table to manipulate the radial depth of cut in real time. For the implementation of cutter runout compensation methodology. cutting force adaptive control was proposed in the angle domain based upon PI (proportional-integral) control strategy to eliminate chip-load change in end milling process. Micro-positioning control due to adaptive acuation force response improves the machined surface quality by compensation or elimination of cutter runout induced cutting force variation. This results will provide lots of information to build-up the precision machining technology.

• Korean Chemical Engineering Research
• /
• v.48 no.1
• /
• pp.80-87
• /
• 2010

Lignite of low rank coal and petroleum coke of high sulfur content can be high potential energy sources for coal gasification process because of their plentiful supply. The kinetic study of steam gasification has been performed in an atmospheric thermobalance with wood chip, lignite, bituminous, anthracite, pet-coke. The effects of gasification temperature($600{\sim}850^{\circ}C$) and partial pressure of steam(30~90 kPa) on the gasification rate have been investigated. The modified volumetric reaction model was applied to the experimental data to describe the behavior of carbon conversion and to evaluate the needed kinetic parameters. Lignite and wood chip with high volatile content showed high average gasification rates comparing to other fuel and thus they might be proper fuel for gasification processes. The activation energies for wood chip, lignite, bituminous, anthracite, and pet-coke through Arrhenius plot were found to be 260.3, 167.9, 134.6, 82.2, 168.9 kJ/mol, respectively. The expression of apparent reaction rates for steam gasification of various chars have been proposed as basic information for the design of coal gasification processes.

• Land and Housing Review
• /
• v.3 no.3
• /
• pp.299-305
• /
• 2012

Various types of bio wood chip for fermentation-extinction of food waste was investigated by comparing their different pore structure with the performance of weight loss rate and microbial activity. The fermentation-extinction of food waste with bio wood chip was examined by adding 700~1,500g of food waste every day during 15 days to the fermentation-extinction reactor with condition of $30{\sim}50^{\circ}C$ temperature and 30~70% humidity, where 1,500g of bio wood chips were existed. The bio wood chips used in this experiment were categorized into 4 different types; microbial-mixing type(A biochip), macro pore type(B biochip) under $2{\mu}m$ of pore size, micro pore type of wood-chips(C biochip) under $0.1{\mu}m$ of pore size, viscous & sticky type(D biochip). As a result, A, B, C, D bio wood chip exhibited 85%, 63%, 92%, 73% weight loss of food waste with fermentation-extinction. The maximum weight loss of food waste was obtained at the fermentation-extinction experiments by using C bio wood chip. On the other hands, the maximum ratio of ATP to COD and TN was obtained from $3.00{\times}10^{-10}$ and $2.31{\times}10^{-11}$ in the case of C bio wood chip, comparing with other types of bio wood chip. Consequently, the performance of weight loss rate was affected with the micro pore structure of bio wood chip which have an advantage of extensive microbial activity space in the fermentation-extinction of food waste.