• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.9
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• pp.1-6
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• 2018

Hydro-forming technology has spread dramatically throughout automotive industry over the last 20 years. This technology has many advantages for automotive applications in terms of better structural integrity of the parts, lower cost from fewer parts, material savings, weight reduction, lower springback, improved strength, durability, and design flexibility. In this study, various simulation technologies were developed to investigate the formability of hydro-forming components. Through this technology, to establish the effective forming process for appropriate components design, the bending process, pre-forming process, die closing process, etc. were considered for good forming. This paper proposes the forming amount, section length (corresponding to the hydro-forming press capacity), and minimum curvature (curvature effect evaluation according to the hydro-forming pressure) among the considerations in the design of the hydro-forming part. In addition, a design method is proposed for hydro-forming molding by carrying out cross section analysis of a real sub-frame part for automobiles. The effects of pre-bending, axial feed, hydraulic pressure, press load, and friction among the hydro-forming process parameters were analyzed. Therefore, whether these processes are necessary factors for hydro-forming were examined.

• Korean Journal of Veterinary Research
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• v.56 no.4
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• pp.255-260
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• 2016

The Ecklonia cava Kjellman by-product (ECBP) as a feed additive was evaluated in improvement of productivity and immune enhancement against Salmonella Gallinarum (SG). Lohmann Brown chickens proved SG-free were randomly divided into 3 groups of 8 chickens each. Chickens were fed with the experimental diet treatment: T0, Non treatment-commercial feed; T1, commercial feed with 0.5% ECBP; T2, commercial feed with 0.1% Lactobacillus plantarum. In this study, we evaluated the effect of T1 and T2 groups on the body weight and protective efficacy against SG in chickens. The results demonstrated that treatment of T1 group as a feed additive affected significantly body weight gaining in chickens. In addition, T1 group showed a significant different colonization of SG when compared to T2 and T0 groups. We also studied that serum IgG and $interferon-{\gamma}$ levels were significantly different compared with other treatment groups. Therefore, we suggest that ECBP can be used as a good candidate of feed additives in chicken industry.

• Korean Journal of Veterinary Research
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• v.53 no.2
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• pp.95-101
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• 2013

The study was carried out to evaluate and compare the immune responses in mice experimentally infected with either wild-type or isogenic mutants of Salmonella enterica serovars Enteritidis (SE), Salmonella Typhimurium (ST) and Gallinarum (SG). The mutant strains were constructed by allelic replacement of some virulence-associated genes in the wild-type strains. Seven-week-old female BALB/c mice were orally or intraperitoneally inoculated by injecting bacterial suspension. To evaluate the immune responses, enzyme-linked immunosorbent assay (ELISA) and enzyme-linked immunospot (ELISPOT) assay were conducted with serum and fecal samples. As a result, the mice group infected orally with the SE mutant strain showed the highest level of specific IgA-secreting splenocytes, compared to the other groups. The peritoneally injected groups showed the greater levels of IgG1 than the orally injected groups, which was in a good agreement with the previous studies. In addition, the mutant infected groups had the similar secretion levels of antibodies with the wild-type infected groups. These results demonstrated that the SE mutant strain elicited humoral immune response as much as wild-type, implying that it can be useful as a delivery vehicle as well as a candidate of a live attenuated vaccine.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.3D
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• pp.355-361
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• 2011

In order to properly evaluate ITS services exposed in SMART Highway project, a confident dynamic origin-destination (OD) is inevitably needed. This paper used WAVE communication information as a part of call and response (C&R) communication which constitutes core part of the technology for constructing OD. This information includes node information and vehicle information (e.g., latitude and longitude) as well as trajectory data and sample path volume date calculated using node information and vehicle information. A procedure developed to construct a dynamic OD and to validate OD is consist of 1) making toy network and one-hour 00 (random distribution), 2) collecting link information and vehicle information, 3) constructing five-minute OD, and 4) validating estimated OD result using traffic volume and travel time simultaneously. The constructed OD is about 84.79% correct within less than 20% error range for 15min traffic volume, and about 85.42%, within less than 20% error rate of 15 min travel time. Some limitations and future research agenda have also been discussed.

• Journal of Biomedical Engineering Research
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• v.22 no.6
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• pp.511-518
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• 2001

In vitro corrosion resistance of the commercially used 76.5wt.%Pd-17.6%Cu-7.2%Ga and 77.3%Pd-6.0%Ga dental Prostheses high-Palladium system alloys in cast, degassing and porcelain-firing heat treatment conditions were evaluated by the potentiodynamic polarization technique in the de-aerated 0.9%NaCl and a modified Fusayama electrolyte. From the corrosion rate experimental results, we found that there is a small difference in the corrosion resistance depending on the microstructure. However. it was so small that there is no significant problem as a dental material. The 77.3%Pd-6.0%Ga showed better corrosion resistance than the 76.5%Pd-11.6%Cu-7.2%Ga dental Prostheses high-palladium system alloys. These experimental observations in 76.5%Pd-11.6%Cu-7.2%Ga alleys are mainly due to a rapid quenching and Cu in the alloy which accelerate the eutectic reaction with a segregation and Precipitates in the microstructure. On the ocher hand, 77.3%Pd-6.0%Ga alloys, which are solid-solution matrix, show much better col·lesion resistance compared with that of 76.5%Pd-11.6%Cu-7.2%Ga alloys.

• Journal of Chest Surgery
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• v.30 no.6
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• pp.613-616
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• 1997

We present a case of 58-year-old (tamale with dilated cardiomyopathy(DCMP) in whom we performed left ventricular(LV) remodeling surgery(Batista operation) to reduce the left ventricle diameter and improve left ventricular unction. The patient was admitted September 1996 with heart failure NYHA class IV. There was severe orthopnea and peripheral edema. 2-D echocardiography(Echo) showed DCMP with the ejection fraction(EF) I5%, LV end diastolic dimension(LVEDD) 80mm, mitral regurgitation(MR) grade IV, tricuspid regurgitation ('m) grade ll. Preoperative cardiac output(CO) was 1.5/L/min and cardiac index(Cl) was 1.0 L/min/m2. We proceeded with LV remodeling surgery by resection a part of LV lateral wall between both papillary muscle, from the mitral annulus to the LV apex. Size of resected LV wall was 90 $\times$ 100 $\times$ 15 mm. At the mean time, mitral valve and tricuspid valve were repaired. Postoperative 2-D Echo showed the EF 37%, LVEDD 50 mna, trivial MR, no TR. CO was 3.SL/min and Cl was 2.3 L/min/m2. Her fuctional NYHA class was 1.

• Journal of Korean Society of Transportation
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• v.22 no.6
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• pp.67-77
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• 2004

A treatment of outlier has been discussed. Outliers disrupt the reliability of information systems and they should be eliminated prior to the information and/or data fusion. A time series-based elimination algorithm were proposed and prediction interval, as a criterion of acceptable value width, was obtained with the model. Ten actual link values were used and the best model was identified as IMA(1,1). Although the actual verification was difficult in a sense that the matching process between the eliminated data and model data was not readily available, the proposed model can be successfully used in practice with some calibration efforts.

• Journal of Korean Society of Transportation
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• v.24 no.5 s.91
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• pp.7-18
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• 2006

Data for travel information Provision are regularly aggregated to Provide travel time information in a reliable and convenient manner and to manage traffic data and information efficiently. In most of practices in Korea, the GPS based travel time data are mainly aggregated every 5 minutes As a result, some probes can't pass by a link within aggregation interval and thereby create uncompleted link passing data. But these data are mostly generated during the congested times and therefore a method that uses such uncompleted link passing data are required. This study estimated queue dissipation length, green time and cycle that use GPS spot speed and developed a link travel time estimation method using such uncompleted link passing data. It also presents method and the overall process of using such data to estimate link travel time in a more accurate manner. As a result, MAPE 1.98% and MAE 4.75 sec of link travel time accuracy improvement has been reported, which is not much different from the real link travel time. The method Proposed here would be an alternative to increase the amount of GPS probe data, especially in congested urban arterial case.

• Journal of Korean Society of Transportation
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• v.28 no.2
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• pp.171-181
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• 2010

The integrated transit fare system of Seoul metropolitan area has given positively evaluated with reduction of user cost and activating the transfer behavior from its opening year, July 2007. However, there were only few research about railway demand forecasting methodology, especially mode share, has conducted under the integrated fare system. This study focuses on the utility estimation by each mode under the integrated fare system, and on the coefficient actualization relates on travel time and travel cost estimation with Household Travel Survey Data 2006. Also the railway demand analysis methodology under various fare systems is presented. The methodology from this study is expected to improve accuracy and usefulness in railway demand analysis.

• Journal of Korean Society of Transportation
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• v.27 no.5
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• pp.113-124
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• 2009

This paper suggests a new approach for providing information for driver safety at signalized intersections. Particularly dangerous situations at signalized intersections such as red-light violations, accelerating through yellow intervals, red-light running, and stopping abruptly due to the dilemma zone problem are considered in this study. This paper presents the development of a dangerous vehicle determination algorithm by collecting real-time vehicle speeds and times from multiple point detectors when the vehicles are traveling during phase-change. For an evaluation of this algorithm, VISSIM is used to perform a real-time multiple detection situation by changing the input data such as various inflow-volume, design speed change, driver perception, and response time. As a result the correct-classification rate is approximately 98.5% and the prediction rate of the algorithm is approximately 88.5%. This paper shows the sensitivity results by changing the input data. This result showed that the new approach can be used to improve safety for signalized intersections.