• Journal of the Semiconductor & Display Technology
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• v.5 no.1 s.14
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• pp.51-55
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• 2006

MgO thin films were prepared through electron-beam deposition onto ITO-coated glass substrates in order to measure electrical, dielectric, and microstructural properties. Design of experiments was performed in this study with the aim to understanding of the effects of processing variables, e.g., substrate temperature and filament current of an e-beam evaporator statistically. Leakage currents, relative dielectric constants, and diffraction intensities of MgO thin films were analyzed statistically, following the analysis procedure provided in the design of experiments. The leakage current level of MgO thin films has been found to be statistically significant at the level of $\alpha=0.1$.

• Proceedings of the Optical Society of Korea Conference
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• 2000.02a
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• pp.68-68
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• 2000

In this paper a very brief review of historical development of optical science and technology in China is presented. More attention has been pain on Modem Optics, which developed since 1950s. The recent development of optical science and technology in following fields are introduced. 1. Optical engineering and instrumentation (tracking theodolites, high speed cameras, satellite laser ranging systems, satellite flying attitude control, cameras for remote sensing, astronomical optical instrument) 2. Applied optics (adaptive optics, optical metrology, infrared optics, optical processing, optical holography) 3. Laser science and technology (ultrashort pulse lasers, UV-X ray lasers, high power laser facilities and laser fusion, laser isotope separation) 4. Laser and nonlinear materials (rare earth elements doped laser glasses and crystals, tunable laser crystals, borate series and organic nonlinear crystals) 5. Optoelectronic science and technology (Optical communication, optical data storage, optical computing) The current situation and developing prospect of optical and optoelectronic industry in China are presented. Furthermore it points out that the optical industry could be developed vigorously only if products development capacity is enhanced and new products industrialization is heightened. The main research and education institutions in the optics field in China, as well as the Chinese Optical Society (COS) are introduced.

• Journal of radiological science and technology
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• v.17 no.1
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• pp.49-54
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• 1994

This study was conducted to find out the medical exposure dose in simple abdomen A-P projection of adults, based on the 87 hospitals located in Seoul. As the results, the following conclusions have been reached; 1. 88.5 % of the surveyed hospitals had the use of $65\;kVp{\sim}79\;kVp(M{\pm}SD:71.45{\pm}4.73\;kVp)$ as tube voltage. 2. 87.35 % of the surveyed hospitals had the use of $50\;mAs{\sim}89\;mAs(M{\pm}SD:64.31{\pm}16.21\;mAs)$ as the amount of current. 3. Shallow doses ranged from 2.00 mSv to 4.99 mSv($M{\pm}SD:3.81{\pm}1.01\;mSv$) in 80.46 % of the surveyed hospitals. 4. Exposure dose was directly depended on the tube voltage or the amount of currents.

• Journal of the Korean Ceramic Society
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• v.17 no.3
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• pp.141-144
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• 1980

Thermal expansion property of $SiO_2-Al_2O_3$ system consisted of Muan clay, Hadong Pink Kaolin and Dangjin Silica was studied. Specimens were heated at the constant rate of 18$0^{\circ}C$/hr to the max. temperatures of 115$0^{\circ}C$ to 130$0^{\circ}C$ with an interval of $25^{\circ}C$, and matured for 3hrs. The result of X-Ray diffraction analysis showed that main crystals formed were $\alpha$-quartz, $\alpha$-cristobalite and mullite. Linear thermal expansion was measured at 90$0^{\circ}C$. The results of the linear thermal expansion were decreased regularly with the increase of the sintering temperature in accordance with the following equation. $y=5$\chi$\perp1100^{\circ}$. Where $\chi$ is amounts of kaolin (wt%), and y is temperature of the changing point of linear thermal expansion.

• Journal of the Korean Applied Science and Technology
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• v.12 no.2
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• pp.145-150
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• 1995

The Kinetics velocity for hydrolysis reaction of vanillylidene imine derivatives has been measured by ultra-violet ray spectrophotometer in 20wt% $dioxane-H_2O$ at $25^{\circ}C$. It was measured the reaction rate Constant of vanillylidene imine derivatives that can be applied widely following to pH-change at $25^{\circ}C$. Final products that hydrolyzed the vanillylidene imine certified in vanillin and aniline derivative, and the effect of substitution radical that has affected on hydrolysis reaction was largely promoted to reaction rate by electron attrating group in acidity and electron donoring group in basic. From the results of rate constant to hydrolysis reaction, substituent radical effect and final products. It has certified the hydrolysis reaction mechanism of vanillylidene imine derivatives.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.18 no.4
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• pp.286-291
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• 2015

Ulcerative colitis (UC) is a chronic idiopathic inflammatory bowel disease. Mesalizine for the first-line therapy of UC has adverse effects include pancreatitis, pneumonia and pericarditis. UC complicated by two coexisting conditions, however, is very rare. Moreover, drug-related pulmonary toxicity is particularly rare. An 11-year-old male patient was hospitalized for recurring upper abdominal pain after meals with vomiting, hematochezia and exertional dyspnea developing at 2 weeks of mesalizine therapy for UC. The serum level of lipase was elevated. Chest X-ray and thorax computed tomography showed interstitial pneumonitis. Mesalizine was discontinued and steroid therapy was initiated. Five days after admission, symptoms were resolved and mesalizine was resumed after a drop in amylase and lipase level. Symptoms returned the following day, however, accompanied by increased the serum levels of amylase and lipase. Mesalizine was discontinued again and recurring symptoms rapidly improved.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.2
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• pp.241-248
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• 2011

This research was performed to evaluate the efficacy of phosphate removal from wastewater by surface-modified wood powder and to clarify the removal mechanisms. In this work, Pinus rigida which is abundant in Korea and has little economic value was used in preparation of the wood powder as a sorbent material. The experiments were carried out in 2 phases, isothermal adsorption test and column test. The results of adsorption test fitted well both the Langmuir and Freundlich isothermal equations. Adsorption capacity was highest with the bark powder followed by the mixed powder(50% bark powder and 50% woody powder) and woody powder. Phosphate removal efficiency was as high as 98% at initial phosphate concentration of 50mg/L. Specific surface area of the powder increased following the experiment and phosphate removal was speculated to occur through adsorption mechanism. Energy dispersive X-ray analysis(EDXA) revealed that the phosphate adsorbed onto the surface of the powder was in the form of strengite($FePO_{4}$).

• Journal of the Korean Society for Heat Treatment
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• v.17 no.5
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• pp.278-282
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• 2004

Effect of pre-treatment on the gas nitriding process of austenitic stainless steels has been investigated and the following results were obtained. Minimum pre-treatment time was decreased to 5min with increasing treatment temperature from $200^{\circ}C$ to $600^{\circ}C$. Surface activation effect by the pre-treatment was maintained in the air up to holding time of 64hr, judging from the analysis result of gas nitrided specimens. The Depth of nitrided layer of STS 304 and 316 stainless steels were ranged from $5{\mu}m$ to $90{\mu}m$ at $440^{\circ}C{\sim}600^{\circ}C$. The X-ray diffraction intensity for austenitic stainless steels were increases as nitriding temperature from $440^{\circ}C$ to $600^{\circ}C$.

• Journal of radiological science and technology
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• v.23 no.2
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• pp.69-73
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• 2000

This paper studied a C-arm's exposure condition and measured scatter rays by thickness and distance. This study reached the following conclusion. 1. Approrimately exposure dose for a patient using fluoroscopy is as follows : 2. Mostly, an operating room was not shielding by lead and operator put on only apron without thyroid and facial part protection. 3. 0.5 mmPb equivalent's apron shielded about 99% of scattered rays at 60 cm from x-ray tube. 4. Scattered rays are depended on distance and thickness so operators are should be careful when using fluoroscopy by C-arm and if possible use high frequency equipment that has a large output.

• Animal Systematics, Evolution and Diversity
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• v.7 no.1
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• pp.39-44
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• 1991

A gobiid fish , Istigobius hoshinonis (Tanaka) is described from one specimen collected at Hanrim-p, Cheju-do , on August 2, 1986. This is the first definitive record of the species in Korean waters. This species is distinguish from its congeners by the combination of the following characters ; uppermost pectoral fin ray unbranched, 12 or more predorsal scales, 7-9transverse scales and no scales on cheek and operculum. Pidan-mang-dug' is proposed as Korean name of this species.