• Proceedings of the IEEK Conference
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• 2000.11b
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• pp.249-252
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• 2000

A new Smart rower IC's based on the Partial SOI technology was designed for such applications as mobile communication systems, high-speed HDD systems etc. A new methodology of integrating a 0.8${\mu}{\textrm}{m}$ BiCMOS compatible Smart Power technology, high voltage bipolar device, high speed SAVEN bipolar device, LDD NMOSFET and a new LDMOSFET based on the Partial SOI technology is presented in this paper. The high voltage bipolar device has a breakdown voltage of 40V for the output stage of analog circuit. The optimized Partial SOI LDMOSFET has an off-state breakdown voltage of 75 V and a specific on- resistance of 0.249mΩ.$\textrm{cm}^2$ with the drift region length of 3.5${\mu}{\textrm}{m}$. The high-speed SAVEN bipolar device shows cut-off frequency of about 21㎓. The simulator DIOS and DESSIS has been used to get these results.

• Journal of Preventive Medicine and Public Health
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• v.47 no.5
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• pp.245-252
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• 2014

Arsenic is a unique element with distinct physical characteristics and toxicity whose importance in public health is well recognized. The toxicity of arsenic varies across its different forms. While the carcinogenicity of arsenic has been confirmed, the mechanisms behind the diseases occurring after acute or chronic exposure to arsenic are not well understood. Inorganic arsenic has been confirmed as a human carcinogen that can induce skin, lung, and bladder cancer. There are also reports of its significant association to liver, prostate, and bladder cancer. Recent studies have also suggested a relationship with diabetes, neurological effects, cardiac disorders, and reproductive organs, but further studies are required to confirm these associations. The majority of research to date has examined cancer incidence after a high exposure to high concentrations of arsenic. However, numerous studies have reported various health effects caused by chronic exposure to low concentrations of arsenic. An assessment of the health effects to arsenic exposure has never been performed in the South Korean population; thus, objective estimates of exposure levels are needed. Data should be collected on the biological exposure level for the total arsenic concentration, and individual arsenic concentration by species. In South Korea, we believe that biological exposure assessment should be the first step, followed by regular health effect assessments.

• 한국태양에너지학회:학술대회논문집
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• 2008.04a
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• pp.252-256
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• 2008

Photovoltaic (PV) modules output changes noticeable with variations in temperature and irradiance. In general it is has been shown that a $1^{\circ}C$ increase in temperature results in a 0.5% drop in output. In this paper, seven PV module types are analyzed for variation in temperature and irradiance, and the resulting output characteristics examined. The 7 modules types utilized are as follows; 3 poly crystalline modules, 2 single crystalline modules, 1 back contact single crystalline module and 1 HIT module. 3 groups of experiments are then conducted on the modules; tests with varying irradiance values, tests with module temperature varying under $25^{\circ}C$ and tests with module temperature varying over $25^{\circ}C$. The experiments results show that as temperature rises the follow is observed; Pmax decreases by 0.6%, Voc decreases by about 0.4%, and Isc increasing by between 0.03%${\sim}$0.08%. In addition, an irradiance decrease of 100 w/m2 translates into a 10% drop in Pmax.

• The Plant Pathology Journal
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• v.26 no.3
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• pp.245-252
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• 2010

An endophytic bacterial strain, Arthrobacter humicola YC6002, was isolated from a surface sterilized root of Korean turf grass (Zoysia japonica) collected from Jinju, Korea. This strain showed inhibitory effect on germination and shoot growth of radish. The inhibition of germination and shoot growth of radish seeds varied depending on the age of culture and the temperature at which it was incubated. The culture filtrate of 1/10-strength Tryptic Soy Broth medium, incubated for 48 hours at $30^{\circ}C$, showed the highest inhibitory effect on radish seed germination and shoot growth (92% inhibition as compared to control). The active compound with seed germination and shoot growth inhibition was purified and identified as 3-phenylpropionic acid. The purified compound had 53% and 93% inhibitory effect on seed germination and shoot growth of radish for 500 and 1000 ppm solutions, respectively.

• Progress in Superconductivity
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• v.3 no.2
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• pp.252-256
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• 2002

We studied YBCO films for current limiting of the resistive type which utilizes a transition from superconducting to normal state caused by exceeding critical current. The films were deposited on sapphire substrates and covered by gold top layer. The current limiting element consists of 2 mm wide YBCO stripes connected in series. A serious problem in using YBCO films for current limiting is inhomogeneities caused by imperfect manufacturing. Therefore simultaneous quench is a difficult problem when elements for current limiting are connected in series. So some researchers have recently proposed using magnetic field and heating for simultaneous quench. We have measured extended exec trim field-current density(E-J) characteristics for current limiting elements of YBCO films in applied magnetic field of 0 - 130 mT. And we have investigated quench characteristics in current limiting elements and between elements of YBCO films in applied magnetic field. The result of the experiments show that the presence of applied magnetic fields induces uniform quench distribution fur the stripes in element at $50V_{rms}$, otherwise non-uniform quenches were observed. And simultaneous quenches between elements were investigated at $150V_{rms}$. We suggest that suppressing the critical current by increased fields due to fault current effectively forced the stripes of higher $J_{c}$(0) to quench, resulting in equalizing quench times.s.s.s.

• Natural Product Sciences
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• v.23 no.4
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• pp.247-252
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• 2017

The methylglyoxal (MGO) trapping constituents from onion (Allium cepa L.) peels were investigated using pre-column incubation of MGO and crude extract followed by HPLC analysis. The peak areas of MGO trapping compounds decreased, and their chemical structures were identified by HPLC-ESI/MS. Among major constituents in outer scale of onion, 2-(3,4-dihydroxybenzoyl)-2,4,6-trihydroxy-3(2H)-benzofuranone (2) was more effective MGO scavenger than quercetin (6) and its 4'-glucoside, spiraeoside (3). After 1 h incubation, compound 2 trapped over 90% MGO at a concentration of 0.5 mM under physiological conditions, but compounds 3 and 6 scavenged 45%, 16% MGO, respectively. HPLC-ESI/MS showed that compound 2 trapped two molecules of MGO to form a di-MGO adduct and compounds 3 and 6 captured one molecule of MGO to form mono-MGO adducts, and the positions 6 and 8 of the A ring of flavonoids were major active sites for trapping MGO.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.3
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• pp.246-252
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• 2015

This paper compared the consistency of the Environment Stress(ES) model and the Potential Risk Assessment Model (PARK model, which was developed based on a Korean mariner risk perception) for the Busan adjacent waterway. Evaluation of accuracy and comparison of these two models have been made by Vessel Traffic Service (VTS) officers in the Busan VTS Centre. The assessment results of Busan waterway show that the PARK model is more consistent than the ES model as follows. (1) The difference between assessment results applying ES model and PARK model with risk degree of VTSOs were 34% and 5% respectively in six typical traffic situations. (2) The assessment using PARK model is more suitable and identical with the VTSOs opinion in his or her duty time.

• Journal of Chest Surgery
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• v.42 no.2
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• pp.252-255
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• 2009

We performed a hybrid procedure for a 58-year-old man with coronary artery disease and a left subclavian artery stenosis. He underwent left subclavian artery stenting and off-pump coronary artery bypass surgery, including grafting the in situ left internal mammary artery to the left anterior descending coronary artery. The post-operative coronary angiogram and computed tomography showed good patency of the graft and stent. He discharged at postoperative 8 days and he has been followed up for six month with an excellent clinical condition.

• Journal of Biosystems Engineering
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• v.33 no.4
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• pp.248-252
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• 2008

An experiment was conducted in order to investigate gasification characteristics of rice husks in a fixed bed, which was a pre-step to design a continuous gasification system. Two air supply levels for gasification were chosen and their effects on the producer gas amount and producer gas composition were discussed. The main components of the producer gas were CO, $CO_2$, $O_2$, $H_2$ and THC (Total HydroCarbon). As airflow rate decreased, more producer gas was produced. The peak amount of CO, $H_2$ and THC were 28%, 7.5% and 0.68% in volume when constant airflow rate of $3.36\;m^3/s$ was used in the batch operation. About 4.5 kg of ash (9%) and condensed water including tars of 6 kg (11%) were produced from 50 kg rice husks in the gasification. Excluding the byproducts, all rice husks seemed to be transformed into producer gas. This gasification study was conducted prior to developing a continuous gasification system for biomass including agricultural byproducts.

• Journal of Dental Anesthesia and Pain Medicine
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• v.17 no.3
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• pp.183-190
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• 2017

Background: It is important to evaluate preoperative anxiety and prepare sedation when performing dental surgery under local anesthesia. Spielberger's State-Trait Anxiety Inventory (STAI) is useful for predicting preoperative anxiety. State anxiety is defined as a subjective feeling of nervousness. Reduction in the number of the state anxiety items (questions) will be clinically important in allowing us to predict anxiety more easily. Method: We analyzed the STAI responses from 1,252 patients who visited our institution to undergo dental surgery under local anesthesia. Multiple linear regression analysis was conducted for 9 groups comprising anxiety level determinations using the STAI; we then developed a coefficient of determination and a regression formula. We searched for a group satisfying the largest number of requirements for regression expression while setting any necessary conditions for accurately predicting anxiety before dental surgery under local anesthesia. Results: The regression expression from the group determined as normal for preoperative state anxiety was deemed the most suitable for predicting preoperative anxiety. Conclusion: It was possible to reduce the number of items in the STAI by focusing on "Preoperative anxiety before dental surgery."