• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.2
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• pp.169-178
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• 2009

The presence of low adhesion at the wheel-rail contact point can result in skid of train wheels, and the skid, in turn, results in flats appearing on the wheels. Thus, anti-skid control has a crucial role for safe braking and prevention from flats that could cause a disastrous train accident. This paper presents dynamic modeling of a tilting train and the brake system of the tilting train, and analyzes the anti-skid logic used in the tilting train. The validity of the analysis is demonstrated via simulation study using Simulink for skid and re-adhesion circumstances of the tilting train.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.796-801
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• 2007

This study was conducted to investigate antioxidant activity and anti-immunological inflammatory effect of Allium victorialis subsp. platyphyllum extracts (AVPEs). Antioxidant activities of AVPEs were determined by free radical scavenging assay and reducing power test. Leaf-part extract had comparatively better antioxidant activity than other-part extracts. Antioxidant activity of extracts had protective effect for human umbilical vein endothelial cells (HUVECs) against superoxide anions secreted from activated neutrophils. Also, we observed AVPEs had inhibitory effects on the adherence of monocytic THP-1 to HUVEC monolayer to the basal level. Inhibitory effect on cell adhesion was caused by suppression of tumor necrosis factor-${\alpha}\;(TNF-{\alpha})-upregulated$ expression of vascular cellular adhesion molecule-1 (VCAM-1) and E-selectin in HUVECs. From these results, we expect to support the evidence of anti-immunological inflammatory effects of Allium victorialis subsp. platyphyllum (AVP) as a Korean traditional pharmaceutical.

• Journal of the Korea Convergence Society
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• v.11 no.10
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• pp.363-368
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• 2020

Background: Intraoperative and postoperative ocular complications are rare. We retrospectively investigated the abnormal ocular findings in patients who underwent arthroscopic shoulder surgery. Methods: The records were investigated of patients who underwent shoulder arthroscopic surgery at our hospital between January 2018 and March 2019. Ocular complications were confirmed by review of medical records. We performed logistic regression analysis to defined the main factors associated with ocular complications. Results: The overall prevalence of postoperative ocular complications was 8.5% (18/211). A significant association was found between anti-adhesion barrier agent and ocular complications (p=0.020). Conclusions: Anti-adhesion barrier agent used during surgery may be the cause of postoperative ocular complication.

• Applied Chemistry for Engineering
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• v.32 no.4
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• pp.371-378
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• 2021

The formation of hydrophilic surface based on polymers has received great attention due to the anti-adhesion of bacteria on solid substrates. Anti-adhesion coatings are aimed at suppressing the initial step of biofilm formation via non-cytotoxic mechanisms, and surfaces applied hydrophilic or ionic polymers showed the anti-adhesion effect for bioentities, such as proteins and bacteria. This is attributed to the formation of surface barrier from hydration layers, repulsions and osmotic stresses from polymer brushes, and electrostatic interactions between ionic polymers and cell surfaces. The antifouling polymer coating is usually fabricated by the grafting method through the bonding with functional groups on surfaces and the deposition method utilizing biomimetic anchors. This mini-review is a summary of representative antifouling polymers, coating strategies, and antibacterial efficacy. Furthermore, we will discuss consideration on the large area surface coating for application to public facilities and industry.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.51 no.1
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• pp.40-47
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• 2002

This paper describes a re-adhesion control method for the Korean High-Speed Train (KHST) with parallel induction motor drive. To keep a traction efficiency and to improve vehicle maintenance, the adhesion characteristics between wheel and rail are analyzed. Also the re-adhesion controller is designed as the subsystem of induction motor vector control. In order to verify performance of the proposed control techniques, the simulation is executed by train model and a downscaled re-adhesion control simulator is utilized. Both simulation and running test results show that good re-adhesion characteristics are obtained.

• Proceedings of the KIEE Conference
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• 2004.07d
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• pp.2423-2425
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• 2004

Mobility of an indoor wheeled robot is affected by adhesion force that is related to various floor conditions. When the adhesion force between driving wheels and the floor decreases suddenly, the robot has slip state. First of all, this paper models adhesion characteristics and slip in wheeled robot. Secondly, the paper proposes estimation method of adhesion force coefficient(AFC) according to slip velocity. In order to overcome this slip problem, optimal slip velocity must be decided for stable movement of wheeled robot. The paper proposes an anti-slip control system based on an ordinary disturbance observer, that is, the re-adhesion control is achieved by reducing the driving torque enough to give maximum adhesion force coefficient. fuzzy logic controller(FLC) is petty useful with slip through that compare fuzzy with PI control for the controller performance. These procedure is implemented using a Pioneer 2-DXE parameter.

• Journal of Korean Neurosurgical Society
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• v.59 no.3
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• pp.250-258
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• 2016

Objective : A common cause of failure in laminectomy surgery is when epidural, peridural, or perineural adhesion occurs postoperatively. The purpose of this study is to examine the efficacy of a temperature-sensitive, anti-adhesive agent (TSAA agent), Guardix-SG$^{(R)}$, as a mechanical barrier for the prevention or reduction of peridural scar adhesion in a rabbit laminectomy model. Methods : Twenty-six mature rabbits were used for this study. Each rabbit underwent two separate laminectomies at lumbar vertebrae L3 and L6, left empty (the control group) and applied 2 mL of the TSAA agent (the experimental group), respectively. Invasive scar formation or inflammation after laminectomy was quantitatively evaluated by measuring the thickness of the dura, the distance from the surface of dura to the scar tissues, the number of inflammatory cells in the scar tissues at the laminectomy site, and the concentration of collagen in histological sections. Results : At 6 weeks postsurgery, the dura was significantly thinner and the distance from the surface of dura to the scar tissues was greater in the experimental group than in the control group (p=0.04 and p=0.01). The number of inflammatory cells was not significantly different in the two groups (p=0.08), although the mean number of inflammatory cells was relatively lower in the experimental group than in the control group. Conclusion : The current study suggests that the TSAA agent, Guardix-SG$^{(R)}$, could be useful as an interpositional physical barrier after laminectomy for the prevention or reduction of adhesion.

• The Transactions of the Korean Institute of Power Electronics
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• v.8 no.4
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• pp.366-374
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• 2003

In electric motor coaches, the rolling stocks move by the adhesive effort between rail and driving wheel. Generally, the adhesive effort is defined by the function of both the weight of electric motor coach and the adhesive effort between rails and driving wheel. The characteristics of adhesive effort is strongly affected by the conditions between rails and driving wheel. When the adhesive effort decreases suddenly, the electric motor coach has slip phenomena. This paper proposes a re-adhesion control algorithm which uses the maximum adhesive effort by instantaneous estimation of adhesion force using load torque disturbance observer. Based on this estimated adhesive effort, the re-adhesion control Is peformed to obtain the maximum transfer of the tractive effort.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.626-631
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• 2004

In electric motor coaches, the rolling stocks move by the adhesive effort between rail and driving wheel. Generally, the adhesive effort is defined by the function of both the weight of electric motor coach and the adhesive effort between rails and driving wheel. The characteristics of adhesive effort is strongly affected by the conditions between rails and driving wheel. When the adhesive effort decreases suddenly, the electric motor coach has slip phenomena. This paper proposes a re-adhesion control algorithm which uses the maximum adhesive effort by instantaneous estimation of adhesion force using load torque disturbance observer. Based on this estimated adhesive effort, the re-adhesion control is performed to obtain the maximum transfer of the tractive effort.

• Journal of the Korean Society for Railway
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• v.8 no.3
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• pp.216-221
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• 2005

In electric motor coaches, the rolling stocks move by the adhesive effort between rail and driving wheel. Generally, the adhesive effort is defined by the function of both the wright of electric motor coach and the adhesive effort between rails and driving wheel. The characteristics of adhesive effort is strongly affected by the conditions between rails and driving wheel. When the adhesive effort decreases suddenly, the electric motor coach has slip phenomena. This paper proposes a re-adhesion control based on disturbance observer and sensor-less vector control. The numerical simulation and experimental results point out that the proposed re-adhesion control system has the desired driving wheel torque response for the tested bogie system of electric coach. Based on this estimated adhesive effort, the re-adhesion control is performed to obtain the maximum transfer of the tractive effort.