• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.2
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• pp.153-155
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• 2006

A major advantage of the area in and around Braunschweig is its concentration of major research institutes and small to large enterprises dealing with different modes of transportation. For many years, aviation has been a particular focus. The research institutes have aircraft and helicopters equipped especially for research projects, as well as other laboratory equipment, allowing simulation and testing of air traffic application both virtually and on real aircraft. In addition, with the Luftfahrtbundesamt (equivalent organization to FAA) and the Bundesstelle $f{\"{u}}r$ Flugunfalluntersuchung (equivalent to NTSB) both located at the Research Airport, it enables direct contact with two key air-traffic safety authorities. The institutes of DLR and the Technical University of Braunschweig are very active in rail transportation applications. Cooperation with the market leader in rail automation - Siemens Rail Automation, also located in Braunschweig - and with other companies in the Braunschweig region means that safety-critical road applications and mobility research is available due to the activities of a number of institutes. Cooperation with Volkswagen (VW) and other companies in the region ensure access to the market leaders' know-how in this sector. Current European activities within framework of the Galileo project offer particularly good opportunities for the Research Airport to leverage its expertise and position itself internationally as a specialist in safety-critical transport applications - the centre is an initiative of Niedersachsen and the Ministry of Economic Affairs, Labour and Transport Location and navigation plays a central role in all modes of transport - air, road and rail. The market is being revolutionized by the increasing integration of GNSS. The realization of the Galileo system will provide additional opportunities for the Research Airport: Galileo as a civil operated system offers service guarantees especially in the area of safety-critical applications in transportation. Notably standards, processes and authorizations related to the certification of safety-critical applications in the areas of air, road and rail transportation are still to be determined. GAUSS, located at the Research Airport Braunschweig, as an European centre of excellence for simulation, testing and certification of safety-critical applications can offer its expertise to validate the services guaranteed by the Galileo concessionaire.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.413-416
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• 2008

Recently, the results of vital tissue test showed that nitrosodimethylamine (NDMA) as a disinfection by-product (DBP), could be regarded as a carcinogen because a tumor was observed in organs. U.S.EPA indicated 0.7 ng/L as exposure concentration of NDMA based on a risk assessment target with a lifetime cancer risk of $10^{-6}$. Several recent studies have shown that UV oxidation could remove NDMA. However, UV oxidation is uneconomical and can reform NDMA after treating. In addition, the treatment mechanism of adsorption has not been founddue to the uncertainty of NDMA pathway. In addtion, NDMA has a radioisotope $^{14}C$-labeled which can be analyzed at low concentration of NDMA by Liquid Scintillation Counter (LSC). This study has investigated NDMA determination using LSC at an extremely low range from 1 to 100 ng/L and NDMA removal by powdered activated carbon (PAC) adsorption. For $^{14}C$-NDMA by LSC, the highest correlation over 99% between count number and NDMA concentrationwas obtained with possibility of $^{14}C$-NDMA concentration up to 1 ng/L. In the presence of PAC ranging from 50 to 10,000 mg/L, $^{14}C$-NDMA was removed from 18% to 97% for Sigma-Aldrich corporation (S-A co.) and from 9% to 93% by PAC for Daejung corporation (Dj co.). Hence it was found that the removal efficiency by PAC adsorption could vary depending on PAC types from different companies. For PAC adsorption capacity of $^{14}C$-NDMA using the Freundlich isotherm, $K_f$ and 1/n of PAC from S-A co. were $2.67\times10^{-3}$ ng/mg and 1.009, while those of PAC from Dj co. were $1.30\times10^{-3}$ ng/mg and 0.994, respectively. Thus, PAC from S-A co. showed twice higher adsorption capacity than Dj co.

• 전력전자학회논문지
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• 제25권2호
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• pp.73-78
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• 2020

In this study, a novel reactive power control scheme is proposed to supply stable reactive power to the distribution line by compensating a ripple voltage of DC link. In a single-phase system, a magnitude of second harmonic is inevitably generated in the DC link voltage, and this phenomenon is further increased when the capacity of DC link capacitor decreases. Reactive power control was performed by controlling the d-axis current in the virtual synchronous reference frame, and the voltage control for maintaining the DC link voltage was implemented through the q-axis current control. The proposed method for compensating the ripple voltage was classified into three parts, which consist of the extraction unit of DC link voltage, high pass filter (HPF), and time delay unit. HPF removes an offset component of DC link voltage extracted from integral, and a time delay unit compensates the phase leading effect due to the HPF. The compensated DC voltage is used as feedback component of voltage control loop to supply stable reactive power. The performance of the proposed algorithm was verified through simulation and experiments. At DC link capacitance of 375 uF, the magnitude of ripple voltage decreased to 8 Vpp from 74 Vpp in the voltage control loop, and the total harmonic distortion of the current was improved.

• 한국지하수토양환경학회지:지하수토양환경
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• 제19권3호
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• pp.94-103
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• 2014

In this study washing efficiency and desorption isotherms for heavy petroleum oil (HPO), Zn, and Pb bound to complex contaminated soils were examined using various soil flushing agents. Sodium dodecyl sulfate (SDS), methanol, ethylene diamine tetraacetic acid (EDTA), and citric acid were selected as soil flushing agents. 3% (w/v) and 4% SDS showed the highest removal efficiency for HPO, but the difference was not statistically significant (p > 0.05). Thus, 3% SDS was chosen as the best soil flushing agent for HPO. In the case of heavy metals, 0.1-M EDTA showed the highest removal efficiencies. But 0.05-M citric acid was selected due to its economic and eco-friendly strengths. The desorption isotherms obtained using Freundlich and Langmuir models indicated that the maximum desorption characteristics ($K_F$ and $Q_{max}$) of HPO with 4% SDS and 90% methanol and heavy metals with 0.1-M EDTA and 0.1-M citric acid, respectively, were markedly lower than in other cases. In addition, when 4% SDS and 90% methanol were used for HPO in the range of $C_e$ higher than 600 mg/L, and when 0.1M citric acid and 0.1M EDTA were used for Zn and Pb in the range of $C_e$ higher than 300 and 100 mg/L, respectively, the distribution constant converged to certain levels. Thus, constant values of $K_U$ and $K_L$ were determined. It was found that these constants represent the maximum desorption capacity and they can be used as distribution coefficients of desorption equilibrium for the flushing agents. The results of this study provided fundamental information for the selection of the best agents as well as for the process design and operation of soil washing/soil flushing of complex contaminated soils.

• Journal of Chest Surgery
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• 제49권1호
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• pp.1-8
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• 2016

More than a century ago, the first scientific report was published about fracture fixation with plates. During the 1950's, open reduction and plate fixation for fractures were standardized by the founders of Arbeitsgemeinschaft $f{\ddot{u}}r$ osteosynthesefragen/Association for the Study of Internal Fixation. Since the introduction of plate fixation for fractures, several plates and screws have been developed, all with their own characteristics. To accomplice more fracture stability, it was thought the bigger the plate, the better. The counter side was a compromised blood supply of the bone, often resulting in bone necrosis and ultimately delayed or non-union. With the search and development of new materials and techniques for fracture fixation, less invasive procedures have become increasingly popular. This resulted in the minimally invasive plate osteosynthesis (MIPO) technique for fracture fixation. With the MIPO technique, procedures could be performed with smaller incisions and thus with less soft tissue damage and a better preserved blood supply. The last 5 years rib fixation has become increasingly popular, rising evidence has becomeavailable suggesting that surgical rib fixation improves outcome of patients with a flail chest or isolated rib fractures. Many surgical approaches for rib fixation have been described in the old literature, however, most of these techniques are obscure nowadays. Currently mostly large incisions with considerable surgical insult are used to stabilize rib fractures. We think that MIPO deserves a place in the surgical treatment of rib fractures. We present the aspects of diagnosis, preoperative planning and operative techniques in regard to MIPO rib fixation.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.227-227
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• 2010

동력 전달을 위한 구동 부품에 대한 내마모성 개선을 통한 에너지 효율 및 부품의 수명 향상에 대한 사회적 관심이 급증하고 있다. 특히, 최근에는 자동차용 구동부품에 저마찰 내마모 특성이 우수한 Mo-N-Cu 나노복합체 박막에 대한 연구가 활발하게 진행되고 있다. 본 연구에서는 Mo-N-Cu 나노복합체 박막을 마그네트론 스퍼터링 증착법을 활용하였고, 이때 Mo 및 Cu 타겟을 적용하여 동시에 증착하였다. 진공 챔버의 진공도는 $5{\times}10^{-6}\;Torr$ 이하의 초기 진공도를 확보한 이후, 알곤 및 질소 가스를 주입하여 공정 압력이 5 mTorr 수준이 되도록 하였다. 이때 N2/(Ar+N2) = 0.5를 유지하였다. Mo-N-Cu 박막내에 Cu 함량 변화를 위해 Mo 캐소드는 D.C. 1 kW로 고정하고 Cu 캐소드에 R.F. 파워를 0, 40, 60, 80 W로 변화하였다. 박막의 두께는 증착시간을 변화하면서 $1\;{\mu}m$ 이상이 되도록 하였다. Cu 캐소드에 인가된 파워의 변화에 따라 Mo-N-Cu 박막내 Cu 함유량은 10 at.%까지 변화되는 것을 EDX 분석을 통해 확인하였다. 또한 증착된 Mo-N-Cu 박막의 표면 및 단면에 대한 FE-SEM 분석을 통하여 전형적인 주상구조를 지닌 MoN 박막에서 Cu 함량이 증가할수록 Mo-N-Cu 박막의 결정성을 방해하는 것을 확인하였다. 또한 XRD 분석을 통하여 박막의 결정 구조 분석을 하였고, Nano Indentor를 통하여 30 GPa 수준의 고경도를 지닌 박막이 형성됨을 확인하였다. 박막의 내마모 특성 평가를 위해 ball-on-disk 트라이보미터를 활용하여 마찰계수 평가를 수행하였고, Cu 함유량의 변화에 따라 마찰계수가 MoN 박막의 경우 0.8에서 Cu 함량이 5 at.%에서 0.15로 급격하게 낮아짐을 확인하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.475-475
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• 2010

We have generated Ar plasma in dense plasma focus device with coaxial electrodes for extreme ultraviolet (EUV) lithography and investigated an emitted visible light for electro-optical plasma diagnostics. We have applied an input voltage 4.5 kV to the capacitor bank of 1.53 uF and the diode chamber has been filled with Ar gas of pressure 8 mTorr. The inner surface of the cylindrical cathode has been attatched by an acetal insulator. Also, the anode made of tin metal. If we assumed that the focused plasma regions satisfy the local thermodynamic equilibrium (LTE) conditions, the electron temperature and density of the coaxial plasma focus could be obtained by Stark broadening of optical emission spectroscopy (OES). The Lorentzian profile for emission lines of Ar I of 426.629 nm and Ar II of 487.99 nm were measured with a visible monochromator. And the electron density has been estimated by FWHM (Full Width Half Maximum) of its profile. To find the exact value of FWHM, we observed the instrument line broadening of the monochromator with a Hg-Ar reference lamp. The electron temperature has been calculated using the two relative electron density ratios of the Stark profiles. In case of electron density, it has been observed by the Stark broadening method. This experiment result shows the temporal behavior of the electron temperature and density characteristics for the focused plasma. The EUV emission signal whose wavelength is about 6 ~ 16 nm has been detected by using a photo-detector (AXUV-100 Zr/C, IRD). The result compared the electron temperature and density with the temporal EUV signal. The electron density and temperature were observed to be $10^{16}\;cm^{-3}$ and 20 ~ 30 eV, respectively.

• 동의신경정신과학회지
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• 제3권2호
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• pp.65-85
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• 1992

To study the personality characteristics of alcoholic patients, they were screned with the MAST(Michigan Alcoholism Screening Test) and administered with the MMPI (Minnesota Multiphasic Personality Inventory) in the Dept. of Neuropsychiatry, Oriental Medical Hospital in Kyung Hee Univ. form March 1991 to June 1991. Patients admitted for alcoholism were examined and analyzed using the above tests and then studied by Sasang Constitutional approach. Results were as follows; 1. In the MAST score, the cases of obvious alcohol dependence was 53.3% and overall mean score was 28.1 point. 2. In the MMPI scale, the mean of the T-scores for 2(D)-4(Pd) profile was high, but it was not statistically significant. 3. The results obtained by multivariate cluster analysis of MMPI T-scores can be divided into 3 subgroups; 1) 9% showed the psychiatric tendency of F-6(Pa)-9(Ma)profile, 2) 44.2% showed no significant profile, 3)46.5% showed the neurotic tendency of 1(Hs)-2(D)-3(Hy)-4(Pd) profile. 4. Since 44.2% showed no significant profile on the MMPI, much more alcoholic patients were caused not by personality factors but by social tolerance, and also by increasing apportunities of drinking in Korean society. 5. When analyzed with Sasang Constituional approach, 1) for the Soyangin (少陽人): 6(Pa) scale was particularly high, 1(Hs) and 3(Hy) scales were low compared to others, 2) for the Taiumin(太陰人): 1(Hs)-2(D)-3(Hy)-4(Pd) neurotic profile was high, the K-scale and 4(Pd)scale were high compared to the Soyangin, 3) for the Soumin(少陰人): 1(Hs)-2(D)-3(Hy)-4(Pd) neurotic profile and 7(Pt) scale were also high.

• Restorative Dentistry and Endodontics
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• 제25권2호
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• pp.235-242
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• 2000

The purpose of this in vitro study was to evaluate the sealing ability of three sealers(Sealapex, Pulp canal sealer, AH26) used with continuous wave method using an anaerobic bacterial leakage model. 53 extracted human teeth with straight and single canals were prepared with crown-down pressureless technique using .04, .06 taper Profile(Maillefer, Swiss). Master apical file was maintained as #35 K-file. All canals of the experimental teeth were obturated with continuous wave method using System B(Analytic technology, U.S.A.) The teeth were randomly divided into three experimental groups of 15 and two control groups of 4. Experimental group 1 was obturated with Sealapex and group 2 with Pulp canal sealer, and group 3 with AH26. A dual chamber anaerobic bacterial leakage model was assembled. Brain heart infusion with yeast extract, hemin, menadion, and the chromogenic indicator bromocresol purple was used as the culture broth for Fusobacterium nucleatum(VPI 10197), The specimens were incubated in anaerobic chamber at $37^{\circ}C$ and were observed every 2 to 3 clays, The coronal leakage was evaluated through the color change of culture broth in lower chamber for 60 days. The results were as follows: 1. The incidence of bacterial leakage in group 1 (Sealapex group was 80%, 53% in group 2 (Pulp canal sealer), 27% in group 3 (AH26). 2. There were statistically significant differences in leakage scores between group 1 and group 2, and between group 1 and group 3, respectively. (P<0.05) 3. There was no significantly difference in leakage score between group 2 and group 3. (P>0 05)

• Journal of Radiation Protection and Research
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• 제2권1호
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• pp.24-30
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• 1977

P.W.R. 형 원자로 증기발생기에서 발생되는 배수는 방사성 물질에 의하여 오염된다. 일반적으로 이 원자로의 증기발생기에 공급되는 급수는 'Phosphate'로 pH를 조절했으나 근래에는 'Ammonia' 조절방법이 선진제국에서 각광을 받고 있는 실정인 바 이는 약알카리로 pH를 조절하여 장치의 부식을 방지하기 위함이다. 본 실험에서는 이온 교환 수지탑을 이용하여 'Ammonia'로 조절된 배수를 처리하는 실험을 하였는 바, Acid Form의 Carboxylic, Cationic 몇 Anionic Ion Exchange Resinces Columns의 직열상태로 운전하였을 시 $^{137}Cs$과 $^{90}Sr$의 제염계수(Decontamination Factor)가 가장 높은 값을 나타낼 수 있으며 또한 그 처리능력이 가장 양호한 편으로 판명되었다.