• Computers and Concrete
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• v.17 no.2
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• pp.189-199
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• 2016

Chloride penetration is considered as a most crucial factor for the determination of the service life of concrete. A lot of experimental tools for the chloride penetration into concrete have been developed, however, the mechanism was based on only diffusion, although permeability is also main driving forces for the chloride penetration. Permeation reacts on submerged concrete impacting for short to long term durability while capillary suction occurs on only dried concrete for very early time. Furthermore, hydrostatic pressure increases in proportional to measured depth from the surface of water because of the increasing weight of water exerting downward force from above. It is thought, therefore, that the water pressure has a great influence on the chloride penetration and thereby on the service life of marine concrete. In this study, new experiment is designed to examine the effect of water pressure on chloride penetration in concrete quantitatively. As an experiment result, pressure leaded a quick chlorides penetration by a certain depth, while diffusion induced chlorides to penetrate inward slowly. Therefore, it was concluded that chloride should penetrates significantly by water pressure and the phenomena should be accelerated for concrete exposed to deep sea. The research is expected as a framework to define the service life of submerged concrete with water pressure and compute water permeability coefficient of cementitious materials.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.7 s.178
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• pp.1740-1747
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• 2000

Under repeated rolling, initial plastic deformation introduces residual stresses which render the steady cyclic state purely elastic. This is called the process of shakedown. Many studies have been done about the shakedown in semi-infinite half space using calculated Hertizian pressure. In this paper shakedown processes in a shaft are studied by finite element analyses of a two dimensional(plane strain) model with elastic-linear-kinematic-hardening-plastic material subjected to repeated, frictionless rolling contact. Symmetric and non-symmetric pressure distributions are obtained using a simplified model of the bearing-shaft assembly. The rolling contact is simulated by repeatedly translating both pressure distributions along the surface of the shaft. By the influence of the non-symmetric pressure, larger residual radial tensile stress is generated in the immediate subsurface layer, which may make a crack propagate and, the subsurface undergoes a zigzag plastic deformation during the shakedown process, which may lead to a crack initiation.

• The Korean Journal of Pain
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• v.22 no.1
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• pp.1-15
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• 2009

Neuropathic pain is often refractory to intervention because of the complex etiology and an incomplete understanding of the mechanisms behind this type of pain. Glial cells, specifically microglia and astrocytes, are powerful modulators of pain and new targets of drug development for neuropathic pain. Glial activation could be the driving force behind chronic pain, maintaining the noxious signal transmission even after the original injury has healed. Glia express chemokine, purinergic, toll-like, glutaminergic and other receptors that enable them to respond to neural signals, and they can modulate neuronal synaptic function and neuronal excitability. Nerve injury upregulates multiple receptors in spinal microglia and astrocytes. Microglia influence neuronal communication by producing inflammatory products at the synapse, as do astrocytes because they completely encapsulate synapses and are in close contact with neuronal somas through gap junctions. Glia are the main source of inflammatory mediators in the central nervous system. New therapeutic strategies for neuropathic pain are emerging such as targeting the glial cells, novel pharmacologic approaches and gene therapy. Drugs targeting microglia and astrocytes, cytokine production, and neural structures including dorsal root ganglion are now under study, as is gene therapy. Isoform-specific inhibition will minimize the side effects produced by blocking all glia with a general inhibitor. Enhancing the anti-inflammatory cytokines could prove more beneficial than administering proinflammatory cytokine antagonists that block glial activation systemically. Research on therapeutic gene transfer to the central nervous system is underway, although obstacles prevent immediate clinical application.

• Journal of Korean Society for Atmospheric Environment
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• v.17 no.4
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• pp.321-329
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• 2001

This study included three experiments to evaluate in-vehicle exposures to PM10 and CO: 1) evaluation of in-passenger car exposures, 2) evaluation of in-public bus exposures, and 3) simultaneous evaluation of in-passenger car and in -university bus exposures. The tests of four factors (transportation mode, passenger-car type, commute period, and commute season were focused. A total of 40 actual passenger car commuters, 20 public bus commuters, and four university buses were recruited or surveyed. The same commuters ware participated in both the summer and winter studied. Two factory such as transportation mode and passenger-car type were found to have little effect on the in-vehicle levels of PM10 and CO. Commute period was found to have little effect on the in-vehicle CO levels. Conversely, the other factor, commuting season was found to influence on the in-vehicle levels of PM10 and CO. The present study also confirmed that under the Korean commute conditions, vehicle interiors are an important microenvironment for exposure to PM10 and CO. This was supported by finding that the in-vehicle Air levels were much higher than ambient air levels reported by several previous studies. The mean in -vehicle PM10 concentrations were 114 and 103$\mu\textrm{g}$/m$^3$for passenger cars and public buses, respectively. For CO, the mean in-vehicle concentrations were 2.9 and 2.6 ppm for passenger cars and public louses, respectively.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.4
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• pp.385-391
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• 2008

To effectively cope with a complexity of kinematic metrology due to workspace enlargement of the planar stage, the linear induction motor is suggested as its new driving source. Especially, the linear induction motor under uniform plate type of secondary doesn't inherently have a periodical force ripple which is generally shown in the brushless DC motor. But, it presents a poor transient characteristic at zero or low speed zone owing to time delay of flux settling, resulting in slow response. To improve the servo property of linear induction motor and apply successfully it to the precision stage, this paper discusses a modified vector control methodology. The controller has a novel input form, fixed d-axis current, q-axis current and forward-fed DC current, to control thrust force and normal force of the linear induction motor independently. Influence of the newly introduced input and the feasibility of controller are validated experimentally.

• Asian Journal for Public Opinion Research
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• v.5 no.3
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• pp.192-203
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• 2018

Alcohol consumption among soldiers impairs health status, performance, and increases the risks of injuries and violence. This study examined drinking behaviors, health problems, and violence among enlisted soldiers at Adisorn military unit in Saraburi, Thailand. Data collection using self-reported questionnaires were distributed to 256 enlisted male soldiers in May 2017. Participants were age 20-22 (93%), Buddhists (98%), high school education or lower (93%). They purchased alcohol at their own expense (46.5%). For alcohol consumption, all were lifetime drinkers (100%). The current drinking patterns were different 28.5% were current drinkers, 65.5% are currently abstaining from drinking (64.5%), and 6.6% stopped drinking permanently. The top three alcohol beverages were beer (52.3%), brandy (25.0%), and hard liquor (19.5%). Problems related to alcohol were from lost balance/falls (6.7%), illness (10.2%), driving under the influence (19.5%), and accidents (24.2%). Violence from drinking in the past month was from fighting (28.1%). This study is the first to provide information about alcohol-related problems in enlisted male soldiers. There is the need to offer straightforward advice, brief counseling, and refer soldiers to receive treatment to prevent alcohol-related problems. Online social media and web-based programs were recommended as platforms to provide preventive alcohol message to the enlisted.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.4
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• pp.399-404
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• 2011

Overload vehicles have demoralizing influence upon the social overhead capital, economics of nation, traffic flow and road safe as various components. Accordingly, this study established a ubiquitous sensor network system to develop an intelligent regulation system to monitor overloaded vehicles in motion. and Unlike WIM, after detecting the axle of driving vehicles by measuring deformation of roads, this system calculates the weights of vehicles by using signals from the strain sensors installed under the road and an analysis method. Also the study conducted an simulation test for vehicle load analysis using genetic algorithm. and tested wireless sensor for USN system.

• Journal of Distribution Science
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• v.22 no.6
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• pp.95-106
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• 2024

Purpose: This study investigates the complex dynamics of consumer behavior in Vietnamese banking omnichannel environments, focusing on the roles of service consistency, service transparency, flow, perceived privacy risk, and loyalty intention. Research design, data and methodology: Using a sample of 422 Vietnamese bank customers, data analysis revealed significant relationships among the variables under investigation. Results: Firstly, service consistency was found to positively influence flow experiences and negatively impact perceived privacy risk, highlighting the importance of uniform service quality across channels in enhancing consumer engagement while mitigating privacy concerns. Similarly, service transparency was positively associated with flow experiences and negatively associated with perceived privacy risk, underscoring the importance of transparent information dissemination in fostering immersive consumer experiences while alleviating privacy apprehensions. Furthermore, both flow experiences and perceived privacy risk significantly influenced loyalty intentions, indicating the pivotal roles of engaging experiences and data security in driving consumer loyalty. Additionally, mediated relationships were observed, demonstrating the interplay between service consistency, service transparency, flow, perceived privacy risk, and loyalty intention in shaping consumer behavior in omnichannel contexts. Conclusions: These findings provide valuable insights for retailers and marketers seeking to optimize consumer experiences and cultivate loyalty in omnichannel environments by prioritizing consistency, transparency, and data privacy protection.

• Journal of IKEEE
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• v.23 no.3
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• pp.978-983
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• 2019

Under the influence of Autonomous Driving and AI, it is important to accurately recognize and judge objects through cameras. In particular, since a method of recognizing an object using a camera can obtain a large amount of information visually compared to other methods, many image signal processing methods have been studied to extract an accurate image. In addition, a lot of research is being carried out to implementation about hardware. In this work, we compare the principles and characteristics of the sorting algorithms that are frequently used in image signal processing and summarize the performance evaluation. Based on this, we define an efficient algorithm when implemented in hardware among efficient sorting algorithms.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.04a
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• pp.155-158
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• 2000

Influence of sustain pulse-width on electro-luminous efficiency is experimentally investigated for surface discharge of AC-PDP. A square pulse with variable duty ratio and rising time of 300 ns has been used in the experiment. It is found that the firing voltage is decreased as the pulse-width is increased from 2 ${\mu}s$ to 8 ${\mu}s$ with sweeping frequency range of 10 kHz to 50 kHz. It has been found that the optimal sustain pulse-width is in the range of $3{\sim}4{\mu}s$ under driving frequency range of 30 kHz and 50 kHz, based on observation of memory coefficient, wall charge, and wall voltage as well as luminous efficiency.