• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.10
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• pp.494-501
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• 2000

This paper describes a strategy of a daily optimal operational scheduling in cogeneration system for paper mill. The cogeneration system selected to establish the scheduling consists of three units and several auxiliary devices. One unit generates electrical and thermal energy using the back pressure turbine. The rest two units generate the energy using the extraction condensing turbine. Three auxiliary boilers, two waste boilers and three sludge incinerators operate to supply energy to the loads with three units. The cogeneration system is able to supply enough the thermal energy to the thermal load, however it can not sufficiently supply the electrical power to the electrical load. Therefore the insufficient electric energy is compensated by buying electrical energy from utility. When the operational scheduling is performed considering the environmental problem. This paper shows the simulation results for daily operational scheduling obtained using the evolutionary algorithm. This results reveal that the proposed modeling and strategy can be effectively applied to cogeneration system for paper mill.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.51 no.8
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• pp.360-367
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• 2002

In this paper, genetic algorithm based adaptive image enhancement filtering scheme is proposed and Implemented on FPGA board. Conventional filtering methods require a priori noise information for image enhancement. In general, if a priori information of noise is not available, heuristic intuition or time consuming recursive calculations are required for image enhancement. Contrary to the conventional filtering methods, the proposed filter system can find optimal combination of filters as well as their sequent order and parameter values adaptively to unknown noise types using structured genetic algorithms. The proposed image enhancement filter system is mainly composed of two blocks. The first block consists of genetic algorithm part and fitness evaluation part. And the second block consists of four types of filters. The first block (genetic algorithms and fitness evaluation blocks) is implemented on host computer using C code, and the second block is implemented on re-configurabe FPGA board. For gray scale control, smoothing and deblurring, four types of filters(median filter, histogram equalization filter, local enhancement filter, and 2D FIR filter) are implemented on FPGA. For evaluation, three types of noises are used and experimental results show that the Proposed scheme can generate optimal set of filters adaptively without a pioi noise information.

• Journal of the Korean Ceramic Society
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• v.40 no.2
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• pp.167-171
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• 2003

CMP(Chemical Mechanical Planarization) slurry for STI process is made by mechanically synthesized$CeO_2$as abrasive. The abrasive can be stabilized by electrostatic or steric stabilization in aqueous slurry and steric stabilization is more effective for long-term stability. Blanket-type$SiO_2$and $Si_3N_4$ wafers are polished with CMP slurry containing$CeO_2$synthesized in 50$0^{\circ}C$ or $700^{\circ}C$. Removal rate and surface uniformity of$SiO_2$and$Si_3N_4$wafer and selectivity are influenced by synthetic condition of abrasive, suspension stability and pH of slurries.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.395-396
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• 2008

There is difficulty in predicting the program efficiency of NOR type nonvolatile memory device adopting channel hot electron injection (CHEI) as program operation mechanism accurately since MOSFET on SOI has floating body. In this study, the dependence of program efficiency for SOI nonvolatile memory device of 200 nm channel length on SOI depletion conditions, partial depletion and full depletion, was quantitatively investigated with the aid of numerical device simulation [1].

• Journal of the Korean Institute of Telematics and Electronics D
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• v.36D no.11
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• pp.33-44
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• 1999

The boundary element method was newly implemented into an optical lithography simulator so that it could evaluate rigorously the topological effects of 2dimensional phase-shifting masks. Both transparent and periodic boundary conditions were applied for the method, and the continuity conditions were used for treating interface nodes. The accuracy of the module developed for simulating aerial images was verified by comparison with analytic solutions and published results. In addition, it was found that our simulator would be more efficient than the conventional method based on the rigorous coupled wave analysis in views of the convergence and the calculation speed. Finally, the optimal design of two phase-shifting masks was performed.

• Toxicological Research
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• v.18 no.2
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• pp.195-203
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• 2002

This study was performed to evaluate single and repeated-dose toxicities oj a new cophalosporin antibiotic agent IDC-7l81 in Sprague-Dawley rats. IDC-7181 was injected intravenously to rats at dose levels of 0, 3.2, 16, 80, 400 and 2,000 mg/kg/day for single-dose toxicity study and at dose levels of 0, 10, 50 and 250 mg/kg/day for 4-week repeated-dose toxicity study. In both studies, there were no dose-related changes in mortality clinical signs, body weight changes, food and water consumption, opthalmoscopy, organ weights, urine analysis, biochemical examination, and hematological findings of all animals treated with IDC-7l8l. Gross and histopathological findings revealed no evidence of specific toxicity related to IDC-7181. These results suggest that the intravenous maximum tolerated dose value of IDC-7181 may be over 250 mg/kg and $LD_{50}$ value may be over 2,000 mg/kg in rats.

• Journal of Power System Engineering
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• v.17 no.1
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• pp.97-103
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• 2013

Press machine has advantages over other manufacturing machine which can produce large quantities of products in short time so it is widely used in lots of industrial sectors. To obtain the vehicle's weight lightening and rigidity of the body-frame by applying 'Hot stamping' technique is increasing in the automotive field. In this paper, to improve the irregular vibration arose by 800Ton hot stamping press, the research was continued. Bed, slide and main frame are the key part of working precision, so perform structural analysis was conducted, and based on the analyzing results, structural changes were done on the parts where structural deformation occurred.

• The Korean Journal of Food And Nutrition
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• v.10 no.3
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• pp.325-329
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• 1997

A inulinase of garlic(Seosan) was partially purified by ammonium sulfate fractionation and Sephadex G-150 gel filtration chromatography with a recovery of 9.1%. Optimum temperature and pH of the enzyme were 4$0^{\circ}C$ and pH 6.0, respectively, and the enzyme was stable below 7$0^{\circ}C$ and in the pH range of 5.0~8.0. The enzyme was strongly inhibited by metal ions(Al3+, Mn2+, Hg2+, Cd2+) and EDTA, and the Km value for inulin was 0.22%.

• Journal of ILASS-Korea
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• v.19 no.4
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• pp.216-220
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• 2014

This paper presents effect of nozzle hole number on atomization characteristic of DME fuel spray using three different type of injector having the hole number of 6, 7 and 8. For this study, PDPA(phase Doppler particle analyzer) experiment was performed in terms of $T_{ASOE}$ under various injection pressure. To compare general trend of atomization characteristic, the law data were ensemble averaged based on $T_{eng}$ of 0.2 ms. Results showed that the droplet diameter in terms of SMD(Sauter Mean Diameter) was reduced as increase in injection pressure. Increasing the number of hole lead to reduce in droplet diameter, but no significant reduction in diameter was observed between hole number of 7 and that of 8. In addition, increasing the number of hole resulted in decrease in droplet velocity which is considered as the effect of reduction in spray momentum due to decreasing of fuel quantity per each hole.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.6
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• pp.163-168
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• 2011

In this paper, we propose an emotion transfer system based on LED, which presents and transmitts users emotion through Bluetooth and ZigBee using LED light. We propose an emotional LED system interacting multiple LED lighting system and implement the proposed system using smartphone and WPAN network with Bluetooth and ZigBee. For the transmission of data, ZigBee is adopted for each LED lighting system and Bluetooth is utilized for the smartphone. Also, the LED lighting systems which are connected to smartphone have both ZigBee and Bluetooth module for the heterogeneous network. The implemented system shows the validity and applicability of the proposed system.