• 대한임상검사과학회지
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• 제49권1호
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• pp.22-27
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• 2017

The length of hospital stay (LOS) for patients with respiratory virus infections has been reported to depend the virus type and infection severity. However, the impact of co-infections remains unclear. Patients with suspected respiratory virus infections, who visited Dankook University Hospital between December 2006 and February 2014, were included to examine the relationship between co-infections and LOS. Multiplex reverse transcriptase-polymerase chain reactions were used to identify the causative viruses. LOS was analyzed with respect to sex, age, virus, and co-infection. During this period, 5,310 out of the 8,860 patients (59.9%; median age, 1.5 years) were respiratory virus-positive. In respiratory virus-positive patients with single, double, and three-or-more infections, the average LOS was 7.3, 6.7, and 6.6 days, respectively. Longer LOS was observed for older patients and those with human coronavirus OC43 infections compared with adenovirus or respiratory syncytial virus A infections. LOS differed significantly according to age, virus type, and co-infection, but not between double and three or more infections.

• 한국식품과학회지
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• 제18권2호
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• pp.105-109
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• 1986

잣의 향기성분(香氣成分)을 추출(抽出)하는데 우선 Maillard생성물(生成物)의 영향을 피하기 위하여 Soxhlet장치(裝置)에 의한 추출후(抽出後), 수증기증류(水蒸氣蒸溜) 연속추출법(蓮續抽出法)에 의해 추출(抽出)했다. 이 추출물은 다시 Preparative, TLC에 의해 4부분(部分)으로 나누고, 이 모든 fractions을 FID/FTD capillary GC로 동시(同時) 검출(檢出)하고. GC/MS에 의해 109성분(成分)을 동정(同定)했다. 관능기별(官能基別)로 보면 탄화수소(炭化水素) 26성분(成分), aldehydes류(類) 16성분(成分), alcohols류(類) 31성분(成分), ketones류(類) 12성분(成分), esters류(類) 17성분(成分), 산류(酸類) 2성분(成分), 대기(坮基) 11성분(成分), 기타 3성분(成分)이었다.

• Bulletin of the Korean Chemical Society
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• 제35권6호
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• pp.1654-1658
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• 2014

High value-added aromatic aldehydes (e.g. vanillin and syringaldehyde) were produced from heavy fraction of bio-oil (HFBO) via catalytic oxidation. The concept is based on the use of metalloporphyin as catalyst and hydrogen peroxide ($H_2O_2$) as oxidant under alkaline condition. The biomimetic catalyst cobalt(II)-sulfonated tetraphenylporphyrin ($Co(TPPS_4)$) was prepared and characterized. It exhibited relative high activity in the catalytic oxidation of HFBO. 4.57 wt % vanillin and 1.58 wt % syringaldehyde were obtained from catalytic oxidation of HFBO, compared to 2.6 wt % vanillin and 0.86 wt % syringaldehyde without $Co(TPPS_4)$. Moreover, a possible mechanism of HFBO oxidation using $Co(TPPS_4)/H_2O_2$ was proposed by the research of model compounds. The results showed that this is a promising and environmentally friendly method for production of aromatic aldehydes from HFBO under $Co(TPPS_4)/H_2O_2$ system.

• 동력기계공학회지
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• 제20권2호
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• pp.66-72
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• 2016

As a method to improve the equipment reliability, early warning researches that can be detected fault symptom of an equipment at an early stage are being performed out among developed countries. In this paper, when abnormal signal is input to actual normal signal of a pump, early detection studies on pump's fault symptom were carried out with auto-associative kernel regression as an advanced pattern recognition algorithm. From analysis, correlations among power of motor driving pump, discharge flow of pump, power output of pump, and discharge pressure of pump are exited. When the abnormal signal is input to one of those normal signals, the other expected values are changed due to the influence of the abnormal signal. Therefore, the fault symptom of pump through the early-warning index is able to detect at an early stage.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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• pp.713-714
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• 2006

$SF_6$ 가스절연 Recloser는 선로에 일시적인 과전류가 발생하면 개방 후 자동 재투입 하면서 선로의 정상적인 운전상태를 회복하고, 영구 고장 시에는 정해진 Sequence에 따라 개방, 투입을 반복한 후 개방완료 상태에 이르게 하는 보호기기이며, 조작부는 주로 Solenoid Actuator 방식을 채택해왔었다. 그러나 Solenoid Actuator 방식은 구조가 복잡하고 부품수가 많은 단점이 있어 최근에는 사용 부품수를 획기적으로 감소 시키고 조작 신뢰성을 증대시킨 Magnetic Actuator 방식을 채택하여 사용하는 경향을 보이고 있다. 이 Magnetic Actuator 방식은 구조가 간단하고 부품수가 적어 높은 신뢰성을 확보할 수 있고 유지 보수가 거의 필요하지 않는 장점을 가지고 있다. 이에 본 논문에서는 $SF_6$ 가스절연 Recloser의 조작부에 Magnetic Actuator 방식(이하 PMA (Permanent Magnetic Actuator))을 채용 하였으며, 이를 적용하기위한 입력전원 및 투입, 개방 코일을 패러미터로 하여 PMA의 동적특성을 실험하였으며, 이 실험 자료에 근거하여 27[kV] $SF_6$ 가스절연 Recloser의 PMA 조작부를 설계 및 제작하였다.

• 대한화학회지
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• 제58권1호
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• pp.92-99
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• 2014

The pH sensitive hydrogels composed of N-isopropylacrylamide (NIPA) and acryloyl phenylalanine (APA) were prepared by redox polymerization using N,N'-methylenebisacrylamide (MBA) as a crosslinker. Anti-inflammatory and analgesic agent, Keterolac Tromethamine (KT), was loaded successfully into poly(NIPA-co-APA) copolymeric hydrogels by swelling equilibrium method. To understand the nature of drug in the polymeric matrix, the newly synthesized drug loaded poly(NIPA-co-APA) copolymeric hydrogels were characterized by using differential scanning calorimetry (DSC) and X-ray diffraction (XRD) techniques. The scanning electron microscopy (SEM) technique result indicates the spherical smooth surface of the hydrogels. The drug (KT) releasing nature of the poly(NIPA-co-APA) hydrogels was studied in pH 1.2 and 7.4. Effects of drug loading, crosslinking agent, pH and the ionic strength of the external medium on swelling of hydrogels were also investigated.

• ETRI Journal
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• 제34권3호
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• pp.361-368
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• 2012

A complete high-frequency small-signal circuit model of a 40 Gb/s butterfly electroabsorption modulator integrated laser module is presented for the first time to analyze and optimize its electro-optic (E/O) response and reflection characteristics. An agreement between measured and simulated results demonstrates the accuracy and validity of the procedures. By optimizing the bonding wire length and the impedance of the coplanar waveguide transmission lines, the E/O response increases approximately 5% to 15% from 20 GHz to 33 GHz, while the signal injection efficiency increases from approximately 15% to 25% over 18 GHz to 35 GHz.

• 한국유체기계학회 논문집
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• 제18권2호
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• pp.43-47
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• 2015

As water quality regulations have tightened, many studies to improve wastewater treatment efficiency have been performed. In this study, magnetite powder was used to maintain a high concentration of MLSS in lab-scale wastewater treatment system. After magnetite powder injection, MLSS concentration was above 8,000 mg/L and it was 3.2 times higher than control group(2,500 mg/L). In addition, nitrogen removal efficiency and phosphorus removal efficiency comparing with the control group was increased 20.5% and 11%, respectively.

• Toxicological Research
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• 제35권4호
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• pp.343-351
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• 2019

Many in vitro developmental toxicity assays have been proposed over several decades. Since the late 1980s, we have made intermittent attempts to introduce in vitro assays as screening tests for developmental toxicity of inhouse candidate products. Two cell-based assays which were developed two decades apart were intensively studied. One was an assay of inhibitory effects on mouse ascites tumor cell attachment to a concanavalin A-coated plastic sheet surface (MOT assay), which we studied in the early days of assay development. The other was an assay of inhibitory effects on the differentiation of mouse embryonic stem cell to beating heart cells (EST assay), which we assessed more recently. We evaluated the suitability of the assays for screening in-house candidates. The concordance rates with in vivo developmental toxicity were at the 60% level. The EST assay classified chemicals that inhibited cell proliferation as embryo-toxic. Both assays had a significant false positive rate. The assays were generally considered unsuitable for screening the developmental toxicity of our candidate compounds. Recent test systems adopt advanced technologies. Despite such evolution of materials and methods, the concordance rates of the EST and MOT systems were similar. This may suggest that the fundamental predictivity of in vitro developmental toxicity assays has remained basically unchanged for decades. To improve their predictivity, in vitro developmental toxicity assays should be strictly based on elucidated pathogenetic mechanisms of developmental toxicity.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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• pp.1047-1050
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• 1998

This paper describes an advanced prototype of voltage-fed zero voltage soft-switching PWM resonant inverter with an active voltage clamped capacitor, which is put into practice for high-frequency high-power induction-heated appliances. This application-specific quasi-resonant inverter using the latest generation IGBTs for soft-switching can regulate its output power under a principle of a fixed frequency ZVS-PWM strategy. Its operating principle and unique features are presented as compared with a conventional quasi-resonant ZVS inverter for induction-heated cooker, together with its power regulation characteristics on the basis of its simulation and experimental results. The steady-state performances of this inverter developed for multi-burner type induction-heated food cooking appliance are evaluated and discussed from a practical point of view.