• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.240.2-240.2
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• 2013

The device scale of flash memory was confronted with quantum mechanical limitation. The next generation memory device will be required a break-through for the device scaling problem. Especially, graphene is one of important materials to overcome scaling and operation problem for the memory device, because ofthe high carrier mobility, the mechanicalflexibility, the one atomic layer thick and versatile chemistry. We demonstrate the hybrid memory consisted with the metal-oxide quantum dots and the mono-layered graphene which was transferred to $SiO_2$ (5 nm)/Si substrate. The 5-nm thick secondary $SiO_2$ layer was deposited on the mono-layered graphene by using ultra-high vacuum sputtering system which base pressure is about $1{\times}10^{-10}$ Torr. The $In_2O_3$ quantum dots were distributed on the secondary $SiO_2$2 layer after chemical reaction between deposited In layer and polyamic acid layer through soft baking at $125^{\circ}C$ for 30 min and curing process at $400^{\circ}C$ for 1 hr by using the furnace in $N_2$ ambient. The memory devices with the $In_2O_3$ quantum dots on graphene monolayer between $SiO_2$ thin films have demonstrated and evaluated for the application of next generation nonvolatile memory device. We will discuss the electrical properties to understating memory effect related with quantum mechanical transport between the $In_2O_3$ quantum dots and the Fermi level of graphene layer.

• 한국노년학
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• v.28 no.4
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• pp.925-940
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• 2008

As the proportion of old people in contemporary societies steadily increases, the influence on cognitive rehabilitation strategy of the memory deficit associated with normal and pathological aging grows greater as well. This paper reviewed the current memory rehabilitation techniques for older adults. In the first part of this article, human memory systems as a framework for understanding memory aging were considered. In the second part, research findings concerning memory performance in normal aging and Alzheimer's disease were reviewed. Finally, recent evidence for the kinds of memory rehabilitation procedures with proven efficacy were offered. The existent memory rehabilitation technique have focused on prompt of residual explicit memory, use of preserved implicit memory, utilization of memory external memory aids. A suggestion of memory training based on brain plasticity as a novel approach is offered.

• The Korean Journal of Physiology and Pharmacology
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• v.26 no.6
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• pp.415-425
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• 2022

Memory formation in the hippocampus is formed and maintained by circadian clock genes during sleep. Sleep deprivation (SD) can lead to memory impairment and neuroinflammation, and there remains no effective pharmacological treatment for these effects. Myricetin (MYR) is a common natural flavonoid that has various pharmacological activities. In this study, we investigated the effects of MYR on memory impairment, neuroinflammation, and neurotrophic factors in sleep-deprived rats. We analyzed SD-induced cognitive and spatial memory, as well as pro-inflammatory cytokine levels during SD. SD model rats were intraperitoneally injected with 10 and 20 mg/kg/day MYR for 14 days. MYR administration significantly ameliorated SD-induced cognitive and spatial memory deficits; it also attenuated the SD-induced inflammatory response associated with nuclear factor kappa B activation in the hippocampus. In addition, MYR enhanced the mRNA expression of brain-derived neurotropic factor (BDNF) in the hippocampus. Our results showed that MYR improved memory impairment by means of anti-inflammatory activity and appropriate regulation of BDNF expression. Our findings suggest that MYR is a potential functional ingredient that protects cognitive function from SD.

• The Korean Journal of Physiology and Pharmacology
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• v.24 no.1
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• pp.27-37
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• 2020

Neuroinflammation is an important process underlying a wide variety of neurodegenerative diseases. Carvacrol (CAR) is a phenolic monoterpene commonly used as a food additive due to its antibacterial properties, but it has also been shown to exhibit strong antioxidative, anti-inflammatory, and neuroprotective effects. Here, we sought to investigate the effects of CAR on inflammation in the hippocampus and prefrontal cortex, as well as the molecular mechanisms underlying these effects. In our study, lipopolysaccharide was injected into the lateral ventricle of rats to induce memory impairment and neuroinflammation. Daily administration of CAR (25, 50, and 100 mg/kg) for 21 days improved recognition, discrimination, and memory impairments relative to untreated controls. CAR administration significantly attenuated expression of several inflammatory factors in the brain, including interleukin-1β, tumor necrosis factor-α, and cyclooxygenase-2. In addition, CAR significantly increased expression of brain-derived neurotrophic factor (BDNF) mRNA, and decreased expression of Toll-like receptor 4 (TLR4) mRNA. Taken together, these results show that CAR can improve memory impairment caused by neuroinflammation. This cognitive enhancement is due to the anti-inflammatory effects of CAR medicated by its regulation of BDNF and TLR4. Thus, CAR has significant potential as an inhibitor of memory degeneration in neurodegenerative diseases.

• Korean Journal of Cognitive Science
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• v.33 no.1
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• pp.23-50
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• 2022

Source memory is a cognitive process that combines the representation of the origin of the episodic experience with an item. By studying this daily process, researchers have made fundamental discoveries that make up the foundation of brain and behavior research, such as executive function and binding. In this paper, we review and conduct a bibliometric analysis on source memory papers published from 1989 to 2020. This review is based on keyword co-occurrence networks and author citation networks, providing an in-depth overview of the development of source memory research and future directions. This bibliometric analysis discovers a change in the research trends: while research prior to 2010 focused on individuality of source memory as a cognitive function, more recent papers focus more on the implication of source memory as it pertains to connectivity between disparate brain regions and to social neuroscience. Keyword network analysis shows that aging and executive function are continued topics of interest, although frameworks in which they are viewed have shifted to include developmental psychology and meta memory. The use of theories and models provided by source memory research seem essential for the future development of cognitive enhancement tools within and outside of the field of Psychology.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.269-274
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• 1999

As the semiconductor industry enters the next century, we are facing to the technological changes and challenges. Optical lithography has driven by the miniaturisation of semiconductor devices and has been accompanied by an increase in wafer productivity and performance through the reduction of the IC image geometries. In the last decade, DRAM(Dynamic Random Access Memories) have been quadrupoling in level of integration every two years. Korean chip makers have been produced the memory devices, mainly DRAM, which are the driving force of IC＇s(Integrated Circuits) development and are the technology indicator for advanced manufacturing. Therefore, Korean chip makers have an important position to predict and lead the patterning technology. In this paper, we will be discussed the limitations of the optical lithography, such as KrF and ArF. And, post optical lithography technology, such as E-beam lithography, EUV and E-beam Projection Lithography shall be introduced.

• Atmosphere
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• v.22 no.1
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• pp.109-115
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• 2012

We parallelized the CFD_NIMR model, which is a numerical meteorological model, for best performance on both of distributed and shared memory parallel computers. This hybrid parallelization uses MPI (Message Passing Interface) to apply horizontal 2-dimensional sub-domain out of the 3-dimensional computing domain for distributed memory system, as well as uses OpenMP (Open Multi-Processing) to apply vertical 1-dimensional sub-domain for utilizing advantage of shared memory structure. We validated the parallel model with the original sequential model, and the parallel CFD_NIMR model shows efficient speedup on the distributed and shared memory system.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.63-66
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• 2004

The extraordinary intrinsic properties of SiC have made this material a suitable choice to use in high temperature, high frequency, and high voltage applications. In additional to these, SiC could be employed as the based material for nonvolatile memory applications, mainly due to its extremely low thermal-generation rate at room temperature. In this paper, the reasons of using this material in this particular application is presented and the development of the application over the past fifteen years is reviewed.

• Proceedings of the KSRS Conference
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• v.2
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• pp.725-727
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• 2006

The development of GIS and Location-Based Services requires a high-level database that will be able to allow real-time access to moving objects for spatial and temporal operations. MODB.MM is able to meet these requirements quite adequately, providing operations with the abilities of acquiring, storing, and querying large-scale moving objects. It enables a dynamic and diverse query mechanism, including searches by region, trajectory, and temporal location of a large number of moving objects that may change their locations with time variation. Furthermore, MODB.MM is designed to allow for performance upon main memory and the system supports the migration on out-of-date data from main memory to disk. We define the particular query for truncation of moving objects data and design two migration methods so as to operate the main memory moving objects database system and file-based location storage system with.

• Biomolecules & Therapeutics
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• v.21 no.5
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• pp.381-390
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• 2013

The purpose of this study was to examine whether ginsenoside Rg3 (GRg3) could improve learning and memory impairments and inflammatory reactions induced by injecting lipopolysaccharide (LPS) into the brains of rats. The effects of GRg3 on proinflammatory mediators in the hippocampus and the underlying mechanisms of these effects were also investigated. Injection of LPS into the lateral ventricle caused chronic inflammation and produced deficits in learning in a memory-impairment animal model. Daily administration of GRg3 (10, 20, and 50 mg/kg, i.p.) for 21 consecutive days markedly improved the LPS-induced learning and memory disabilities demonstrated on the step-through passive avoidance test and Morris water maze test. GRg3 administration significantly decreased expression of pro-inflammatory mediators such as tumor necrosis factor-${\alpha}$, interleukin-1${\beta}$, and cyclooxygenase-2 in the hippocampus, as assessed by reverse transcription-polymerase chain reaction analysis and immunohistochemistry. Together, these findings suggest that GRg3 significantly attenuated LPS-induced cognitive impairment by inhibiting the expression of pro-inflammatory mediators in the rat brain. These results suggest that GRg3 may be effective for preventing or slowing the development of neurological disorders, including Alzheimer's disease, by improving cognitive and memory functions due to its anti-inflammatory activity in the brain.