• Journal of the Korea Society of Computer and Information
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• v.19 no.4
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• pp.71-79
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• 2014

This paper investigates wideband dual-polarized microstrip antenna with H-shaped coupling slot. These types of antennas are used to prevent deterioration of transmission quality caused by terminal interference or multipath fading, which usually occur when many terminals are used in limited space such as hot-spot zones. The experimental results show that the impedance bandwidth ($SWR{\leq}2$) of 33.98% and the peak gain of 8.58 dBi (at 2.11 GHz) were obtained by the frequency band under 2.7 GHz. The proposed antenna is designed originally for multiple service bands with simple structure and easily be mass-produced for various commercial applications.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.5
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• pp.408-412
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• 2010

The single-phase switched reluctance motor(SRM) generates the positive torque in the restricted section. So, it can not started by itself and the torque ripple is heavier than poly-phase. For self-starting and fixing rotating direction, the rotor should be placed at the rising inductance slope when stationary. The parking permanent magnet locates the rotor in the fixed position, which can be started by it-self. It is very simple and cost effective but has some drawbacks. It affects the rotor during the operation, so the characteristics of motor, such as a torque, speed, and ripple are changed to go bad. This paper presents the detent torque of parking magnet starting device through the finite element analysis and experiments. The finite element analysis is performed at incremental rotor positions over one detent torque cycle for any one pole. The prototype, fabricated in the previous research, is used for the experiments. The inductance, instant torque, and detent torque are calculated using the terminal voltage and phase current. Finally, the finite element analysis result and the experiment result are compared for analysis and validity.

• Advances in pediatric surgery
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• v.4 no.1
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• pp.74-78
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• 1998

Early recognition and surgical treatment of Hirschsprung's disease prevents serious mortality and morbidity from enterocolitis and obstruction. Usually this disease is characterized by a single aganglionic segment of the colon extending distally to the anal margin. In surgical treatment, the surgeon performs a frozen section biopsy to confirm whether there are ganglion cells. If there are intervening ganglionic sites in aganglionic bowel, there may be confusion in diagnosis and treatment. The authors experienced one case of total colonic aganglionosis with skip area. A transverse loop colostomy was performed on a 7 day-old male baby with colon perforation due to Hirschsprung's disease. But intestinal obstruction persisted and required two more operations to find the true nature of the disease. There were aganglionic segments from the anal margin to the terminal ileum 3.7cm proximal to the ileocecal valve. The entire transverse colon and appendix were normally ganglionated.

• Transactions of the KSME C: Technology and Education
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• v.2 no.1
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• pp.39-46
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• 2014

This study presents computational analysis of aerodynamic characteristics of two-dimensional airfoil sections with elastic flap attached at the trailing edge. EDISON_CFD was utilized to simulate the incompressible turbulent flow around the foil and MIDAS_IT was employed to estimate the deflection of the flap under the pressure loading. Using iterative procedure, the terminal deflection was estimated and the resulting lift-drag ratio indicates that the favorable effect of the flap is expected within certain amount of angle of attack.

• Progress in Superconductivity and Cryogenics
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• v.6 no.4
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• pp.17-21
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• 2004

The butt joint was verified to satisfy the thermal stability of the ITER magnet system through the ITER CS model coil test. Since the contact area in the butt joint is limited to the cross section of the cable, it is necessary to analyze and control the joining parameters precisely for improving the DC resistance. It is difficult to simulate the cables, which are composed of a lot of strands, as three-dimensional models using the commercial code. The random numbers were used to simulate many kinds of contact patterns of the strands on the bonding surface for calculating the bonding area and the DC resistance of the butt joint. The calculated DC resistance decreases with an increase of cable filling factor in terminal. The calculated DC resistance of a 0.9 cable filling factor is about 0.48 n-Ohm, which is about one-tenth of that in the CS model coil test when not considering the electrical contact resistance. From this difference, the electrical contact resistance between the strands and copper sheet was calculated.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.28 no.1
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• pp.31-41
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• 2002

The production of matrix matalloproteinases(MMPs) by the UV irradiated skin fibroblast and the degradation of extracellular matrix(ECM) by these enzymes is known as one of the main reasons of photoaging. Recently, Fisher group showed that the MMP expression is mainly regulated by the mitogen-activated protein(MAP) kinas family, such as extracellular signal-regulated kinase(ERK), c-Jun amino-terminal kinase(JNK) and p38, each of which forms a signaling pathway. In this work we first examined the effect of nitric oxide (NO) on the production of MMP-1 and MMP-2 by the human dermal fibroblasts (HDFs). NO is a multifunctional messenger molecule generated from L-arginine and involved in many kinds of signaling pathway. We found that the treatment of HDF with NO donor, sodium nitroprusside (SNP) enhanced the expression of MMPs with or without UV irradiation and the treatment with nitric oxide synthase (NOS) inhibitors resulted in the significant decrease of MMPs production. From these results, we concluded that the production of MMPs by the UV irradiated HDF is regulated through the signaling pathway involving NO and cyclic GMP.

• Journal of Yeungnam Medical Science
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• v.41 no.2
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• pp.128-133
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• 2024

Aortic dissection in pregnant patients results in an inpatient mortality rate of 8.6%. Owing to the pronounced mortality rate and speed at which aortic dissections progress, efficient early detection methods are crucial. Here, we highlight the importance of early chest computed tomography (CT) for differentiating aortic dissection from pulmonary embolism in pregnant patients with dyspnea. We present the unique case of a 38-year-old pregnant woman with elevated D-dimer and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels, initially suspected of having a pulmonary embolism. Initial transthoracic echocardiography did not indicate aortic dissection. Surprisingly, after an emergency cesarean section, a chest CT scan revealed a DeBakey type I aortic dissection, indicating a diagnostic error. Our findings emphasize the need for early chest CT in pregnant patients with dyspnea and elevated D-dimer and NT-proBNP levels. This case report highlights the critical importance of considering both aortic dissection and pulmonary embolism in the differential diagnosis of such cases, which will inform future clinical practice.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.9
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• pp.2216-2222
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• 2014

A recent trend of increasing container traffic volume using reefer container demands continuous management of reefer container in transit. However, reefer containers can only be monitored at terminal or in ship during marine transportation instead of throughout entire section. In the case of inland transportation section using truck or train, monitoring is not possible currently. The reason is because the reefer container monitoring method using PCT recommended by IMO and conventional monitoring methods using TCP/IP, RFID communication require establishing additional communication infrastructure. This paper will propose a new reefer container control device that not only solves these problems and monitors during inland transportation section but also controls reefer container. Using data port attached to every reefer container, the proposed device collects the information of reefer container and using M2M communication technology, it transmits information to server without the need to establish additional communication infrastructure. In addition, it can control the operational status of reefer container upon receiving control information set in server such as temperature of reefer container.

• Development and Reproduction
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• v.5 no.2
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• pp.167-173
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• 2001

To characterize the difference in glycoconjugates of mouse epididymis, lectin labeling of the tissue section was conducted using Ulex europaeus agglutinin I(UEA I), succinylated wheat germ agglutinin(sWGA), and Griffonia simplicifolia lectin-I(GSL-I). UEA I which binds to outer $\alpha$-L-fucose residue that is a terminal sugar of the side chain branched from oligosaccharide chain gave the labeling in the proximal caput epithelia exclusively. Lumen was commonly labeled in all of the organ. It suggested that the glycoconjugates bearing outer $\alpha$ -L-fucose residue were largely expressed in the initial segments ot epididymis and subjected to secretion. GSL-I which binds to terminal $\alpha$ -D-galactosyl residue of glycoconjugates gave the labeling in the cytoplasm of clear cells and basal cells, and cilia in corpus and cauda regions but not in the caput region. There was no vast difference in labeling pattern by sWGA which binds to N-acetyl-glucosamine residue among the epididymal regions. Clear cells in corpus and cauda epithelia showed more intense labeling by sWGA compared to principal cells, suggesting the functional specialization of this type of cells. The labeling intensities of luminal content by UEA I and sWGA decreased in cauda region compared to corpus region suggesting the presence of enzymatic activities responsible for processing the $\alpha$-L-fucose and N-acetyl-glucosamine residues from secreted glycoconjugates. In summary, the difference in glycoconjugates bearing the $\alpha$-L-fucose, $\alpha$-D-galactose, and N-acetyl-glucosamine residues according to the type of epithelial cells and epididymal segments suggests functional specialization and different roles of each segment in the processing of sperm surface antigens during the epididymal transit.

• Journal of Distribution Science
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• v.13 no.10
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• pp.123-133
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• 2015

Purpose - The Korean government has devised intermodal transportation policies and granted subsidies to shippers and logistics companies that made a conversion of transportation means through the policies. This provides support by expanding the complex uniform railroad transportation and overhauling the deteriorated railroad facilities. As for 2013, however, the freight transportation percentage of railroad was 4.5% in tons and 8.5% in ton kilometers. Meanwhile, since the 1990s, developed countries such as the U.S. and Europe have been trying to expand intermodal freight transport with a legal and institutional support to build a logistics system corresponding with social and economic environmental changes. In this study, I set out to examine the effects of the intermodal freight transport policies in the EU and the U.S., and to explore the direction of setting up a rail intermodal transport system in South Korea. Research design, data, and methodology - The paper used a qualitative research methodology through the literature review. First, was an overview of Intermodal transportation in the EU, U.S. and UN. Second, it describes the development of transport in Europe and the U.S. with particular emphasis on intermodal freight transport. Third, it explores the direction of setting up a intermodal freight transport in South Korea. The last section contains concluding remarks. Results - As for the EU, it has been promoting integration between transport and intermodal logistics network designs while utilizing ITS or ICT and supports for rail freight intermodal by giving reduction to a facilities fee or subsidizing for rail freight in order to minimize the cost of external due to freight transport. On the other hand, as for the U.S., it has been made up of an industrial-led operating project and has been promoting it to improve accessibility between intermodal hubs and cargo terminals through intermodal corridor program, and an intermodal cargo hub access corridor projects, etc. Moreover, it has tried to construct intermodal transport system using ITS or ICT and to remove Barrier. As a result, in these countries, the proportion of intermodal freight transport is going to be the second significant transport compared with rail and maritime transport. An Effective rail intermodal transport system is needed in South Korea, as seen in the case of these countries. In order to achieve this object, the following points are required to establish radical infrastructure policy; diversify investment financing measures taken under public-private partnerships, legal responsibilities, improvement of utilization of existing facilities to connect the railway terminal and truck terminal, and enhancement service competitiveness through providing cargo tracking and security information that combines the ITS and ICT. Conclusions - This study will be used as a basis for policy and support for intermodal freight transport in South Korea. In the future, it is also necessary to examine from the perspective of the shipper companies using the rail intermodal transport, ie, recognition of shipper, needed institutional supports, and transportation demand forecasting and cost-effective analysis of the railway infrastructure systems improvement.