• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.1
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• pp.83-88
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• 2002

To increase the device linearities and the breakdown-voltages of FETs, $Al_{0.25}$G $a_{0.75}$As/I $n_{0.25}$G $a_{0.75}$As/A $l_{0.25}$G $a_{0.75}$As partially doped channel FET(DCFET) structures are proposed. The metal insulator-semiconductor(MIS) like structures show the high gate-drain breakdown voltage(-20V) and high linearities. We propose a partially doped channel structure to enhance the device linearity to the homogeneously doped channel structure. The physics of partially doped channel structure is investigated with 2D device simulation. The devices showed the small ripple of the current cut-off frequency and the power cut-off frequency over the wide bias range. bias range.

• Korean journal of applied entomology
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• v.11 no.1
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• pp.37-40
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• 1972

Experiments were carried out to control white-tip nematode, Aphelenchoides besseyi Christie, during the period just before transplanting. The experimental results were summarized as fellows: 1: From a 12-hr to a 24-hr sled-soaking application into 500 times dilutions of Malathion $80\%$ Ec, Sumithion $50\%$ EC and Lebaycid $50\%$ EC were highly effective than other emulsifierble concentrations of chemicals. 2) The water surface application of PSP-204 $5\%$ G, Diazinon $3\%$ G, Nemagon $20\%$ G and Terracurr-P $5\%$ G were effective. 3: Root·dipping application of Sumithion $50\%$ Ec, Lebaycid $50\%$ Ec and Nemagon $80\%$ Ec were more effective chemicals than others.

• Food Science and Preservation
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• v.8 no.3
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• pp.274-278
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• 2001

The antimicrobial extracts of Rheum palmatum and Coptis chinensis root as well as grapefruit seed extract were applied to dipping treatment for keeping qualities of zucchinis, respectively, which were then packed in low density polyethylene films incorporated with 1% antimicrobial extracts and stored at 10$\^{C}$. Dipping and packaging in the antimicrobial agents suppressed the growth of putrefactive microorganisms and the decay ratio of zucchinis. In addition, the loss ratio of ascorbic acid content of zucchinis and their weight were decreased during the storage of zucchinis. Consequently, the combined method of dipping and packaging in antimicmbial agents tumid out to be superior to dipping treatment or film-packaging in the view point of decay ratio and the quality control of zucchinis.

• Journal of Energy Engineering
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• v.2 no.2
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• pp.208-214
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• 1993

Pyrolysis of bituminous coal has been carried out in a two-stage fixed bed reactor to produce high heating value gas(7000 kcal/N㎥) for industrial or town gas usage. The effects of coke catalyst, pyrolysis temperature (468∼565$^{\circ}C$), and catalytic cracking temperature (700∼850$^{\circ}C$) on the product gas properties from pyrolysis of bituminous coal have been determined. From pyrolysis of Dong Jin coal with coke, the carbon deposition on catalyst is found to be less than 5% of product tar and approximately 15% of total energy iii the parent coal can be recovered as high heating value gas. Oil composition in the product tar from the two-stage pyrolysis is higher than that from low-temperature pyrolysis. The tar produced from pyrolysis below 516$^{\circ}C$ can be easily catalytically cracked but, the tar produced above 565$^{\circ}C$ cannot be cracked easily with catalyst. From the product gas analysis, the catalytic cracking temperature should be maintained below 800$^{\circ}C$ since cracking speed of ethylene increases remarkably with the cracking temperature above 800$^{\circ}C$.

• Journal of the Microelectronics and Packaging Society
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• v.8 no.4
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• pp.1-10
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• 2001

Chip-on-glass(COG) mounting of area array electronic packages was attempted by heating the rear surface of a contact pad film deposited on a glass substrate. The pads consisted of an adhesion (i.e. Cr or Ti) and a top coating layer(i.e. Ni or Cu) were healed by the UV laser beam transmitted through the glass substrate. The lather energy absorbed on the pad raised the temperature of a solder ball which is in physical contact with the pad, and formed a reflowed solder bump. The effects of the adhesion and top coating layer on the laser reflow soldering were studied by measuring temperature profile of the ball during the laser heating process. The results were discussed based on the measurement of reflectivity of the adhesion layer. In addition, the microstructures of solder bumps and their mechanical properties were examined.

• Journal of Korean Society for Geospatial Information Science
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• v.5 no.2 s.10
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• pp.121-130
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• 1997

The aim of this study is to forcast the economic impact of Yosu-Kwangyang harbour on the regional employment. Industries in relation to this harbor can be divided into three parts; related industries to harbor(RI), direct dependent industries on harbor(DDI), indirect dependent industries(IDI). Research regions are 4 cities (Yosu, Yochun, Soonchun, Dongkwangyang) and 3 counties (Yochun, Seungju, Kwangyang).In the aspect of employment, the Yosu-Kwangyang harbor produced a good effect in these regions. In 1995, the rates of the dependence on harbor were showed up RI 1.63%, DBI 3.33%, IDI 15.99%, TOTAL 19.95%. In the Suture, the rates may be showed up various results as; in TOTAL rates, 33.59% in 2000, 44.95% in 2005, 48.03% in 2010, 49.82% in 2015.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.6
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• pp.923-930
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• 2002

This study aims at developing dialog system to improve the quality of life of the elderly with a dementia. The proposed system mainly consists of three modules including speech recognition, automatic search of the time-sorted dialog database, and agreeable responses with the recorded voices of caregivers. For the first step, the dialog that dementia patients often utter at a nursing home is first investigated. Next, the system is organized to recognize the utterances in order to meet their requests or demands. The system is then responded with recorded voices of professional caregivers. For evaluation of the system, the comparison study was carried out when the system was introduced or not, respectively. The occupational therapists then evaluated a male subjects reaction to the system by photographing his behaviors. The evaluation results showed that the dialog system was more responsive in catering to the needs of dementia patient than professional caregivers. Moreover, the proposed system led the patient to talk more than caregivers did in mutual communication.

• The KIPS Transactions:PartC
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• v.11C no.1
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• pp.75-80
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• 2004

An iterative soft-decision decoding algorithm of block codes is proposed. With careful examinations of the first hard-decision decoding result, the candidate codewords are efficiently searched for. An approach to reducing decoding complexity and lowering error probability is to select a small number of candidate codewords. With high probability, we include the codewords which are at the short distance from the received signal. The decoder then computes the distance to each of the candidate codewords and selects the codeword which is the closest. We can search for the candidate codewords which make the error patterns contain the bits with small reliability values. Also, we can reduce the cases that we select the same candidate codeword already searched for. Computer simulation results are presented for (23,12) Golay code. They show that decoding complexity is considerably reduced and the block error probability is lowered.

• Korean Journal of Food Science and Technology
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• v.41 no.3
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• pp.350-353
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• 2009

Peanut (Arachis hypogaea) often causes severe allergic reactions in sensitive people. Agglutinin is known to be one of the allergenic proteins in peanut. A polymerase chain reaction (PCR) method was developed to detect peanut ingredients in food using a primer pair corresponding to the agglutinin gene. This primer pair enabled PCR amplification of specific regions of agglutinin DNA from peanut, but not from 11 other nuts, beans, and cereals (pistachio, almond, sunflower seed, pine nut, walnut, soybean, black bean, kidney bean, azuki bean, rice, and black rice). The proposed PCR method successfully identified all of the 6 processed foods containing peanut whereas 13 other processed foods, which don't declare peanuts as an ingredient, were all negative. The detection limit of this method for purified peanut DNA was 100 pg/reaction. The sensitivity of this method was sufficient to detect peanut DNA in soybean DNA mixture which had been spiked with 0.1% peanut DNA.

• Journal of Veterinary Clinics
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• v.32 no.2
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• pp.196-199
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• 2015

A 7-year-old intact female dachshund (Dog 1) and a 17-year-old intact male Yorkshire terrier (Dog 2) were presented for evaluation of mammary gland tumor and a regular checkup, respectively. Incidentally, segmental caudal vena cava aplasia was detected on CT images in both dogs. Absent postrenal segment (Dog 1) or discontinuation of caudal vena cava (Dog 2) were detected, but prerenal segment of caudal vena cava was continued to the dilated azygos vein. Segmental CVC aplasia should be considered when an abdominal vascular anomaly was evaluated with CT angiography in dogs.