• Journal of the korean Society of Automotive Engineers
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• v.6 no.4
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• pp.54-61
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• 1984

Numerical calculation of the flow field past a passenger car was carried out by using a panel method with a small computer of 5Mbyte memory size. The shape of car body was simplified and reconstructed by 2180 panels on which a constant strength sink (or source) was distributed. The separation of flow from the surface and the wake flow were not considered in the calculation because of the computer memory limitation. All of the results of calculation were presented by using a 3-dimensional computer graphics. In spite of small memory size of computer, generally good agreements were obtained, except the separated region, from the comparison of pressure distribution between numerical analysis and wind tunnel experiment with 1/5 scaled model.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.6
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• pp.781-792
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• 2016

This paper presents a new approach to enhance the data retention of logic-compatible embedded DRAMs. The memory bit-cell in this work consists of two logic transistors implemented in generic triple-well CMOS process. The key idea is to use the parasitic junction capacitance built between the common cell-body and the data storage node. For each write access, a voltage transition on the cell-body couples up the data storage levels. This technique enhances the data retention and the read performance without using additional cell devices. The technique also provides much strong immunity from the write disturbance in the nature. Measurement results from a 64-kbit eDRAM test chip implemented in a 130 nm logic CMOS technology demonstrate the effectiveness of the proposed circuit technique. The refresh period for 99.9% bit yield measures $600{\mu}s$ at 1.1 V and $85^{\circ}C$, enhancing by % over the conventional design approach.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.2
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• pp.169-174
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• 2014

As a versatile processing method for nanoscale memory integration, laser-induced epitaxial growth is proposed for the fabrication of vertical Si channel (VSC) transistor. The fabricated VSC transistor with 80 nm gate length and 130 nm pillar diameter exhibited field effect mobility of $300cm^2/Vs$, which guarantees "device quality". In addition, we have shown that this VSC transistor provides memory operations with a memory window of 700 mV, and moreover, the memory window further increases by employing charge trap dielectrics in our VSC transistor. Our proposed processing method and device structure would provide a promising route for the further scaling of state-of-the-art memory technology.

• Toxicological Research
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• v.33 no.2
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• pp.165-171
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• 2017

Bisphenol A (BPA) is a monomer used in a polymerization reaction in the production of polycarbonate plastics. It has been used in many consumer products, including plastics, polyvinyl chloride, food packaging, dental sealants, and thermal receipts. However, there is little information available on the inhalation toxicity of BPA. Therefore, the aim of this study was to determine its inhalation toxicity and effects on the estrous cycle, spatial learning, and memory. Sprague-Dawley rats were exposed to 0, 10, 30, and $90mg/m^3$ BPA, 6 hr/day, 5 days/week for 8 weeks via whole-body inhalation. Mortality, clinical signs, body weight, hematology, serum chemistry, estrous cycle parameters, performance in the Morris water maze test, and organ weights, as well as gross and histopathological findings, were compared between the control and BPA exposure groups. Statistically significant changes were observed in serum chemistry and organ weights upon exposure to BPA. However, there was no BPA-related toxic effect on the body weight, food consumption, hematology, serum chemistry, organ weights, estrous cycle, performance in the Morris water maze test, or gross or histopathological lesions in any male or female rats in the BPA exposure groups. In conclusion, the results of this study suggested that the no observable adverse effect level (NOAEL) for BPA in rats is above $90mg/m^3$/6 hr/day, 5 days/week upon 8-week exposure. Furthermore, BPA did not affect the estrous cycle, spatial learning, or memory in rats.

• International Journal of Industrial Entomology and Biomaterials
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• v.15 no.1
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• pp.39-45
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• 2007

Extracts of adult worker bodies of Vespa simillima in 2 % NaCl or acidified methanol were administered orally to mice for 70 days. Following this period, memory at one-day and one-month periods, and the effects on scopolamine-induced amnesia were examined using a step-through passive avoidance task. Changes in MK-801-induced disability after 8 days of training, and in memory one month after the trial were also assessed. Mice treated with the 2% NaCl extract showed significant improvement in memory in the behavioral tests one month after the trial, whereas mice receiving the extract in acidified methanol, did not differ from the controls in any trial. The results inidicate that Vespa simillima contains substances acting favorably on the cerebral functions of mammals.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.5
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• pp.657-663
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• 2016

In this work, a novel silicon (Si) based floating body synaptic transistor (SFST) is studied to mimic the transition from short-term memory to long-term one in the biological system. The structure of the proposed SFST is based on an n-type metal-oxide-semiconductor field-effect transistor (MOSFET) with floating body and charge storage layer which provide the functions of short- and long-term memories, respectively. It has very similar characteristics with those of the biological memory system in the sense that the transition between short- and long-term memories is performed by the repetitive learning. Spike timing-dependent plasticity (STDP) characteristics are closely investigated for the SFST device. It has been found from the simulation results that the connectivity between pre- and post-synaptic neurons has strong dependence on the relative spike timing among electrical signals. In addition, the neuromorphic system having direct connection between the SFST devices and neuron circuits are designed.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.2
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• pp.434-440
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• 2005

This study was conducted to find out the effect of Bojungikgitanggamibang(BIT) on growth, learning and memory of rats. The effects of BIT on learning and memory performance were examined in normal or memory impaired mice by using water maze task. Memory was impaired by 192 saporin. Body weight and growth of bone and tail of sample group were not significant compared with those of control groups. Acquisition test of water maze revealed that acqusitive ability of sample group significantly improved on 4,5th day compared with control group, while retentive ability of sample group was not significant. ChAT cell numbers of medial septum of sample group was significant compared with control group, and so was those of CA1, CA2 parts of hippocampus. On ChAT cell numbers of hippocampus, in CA2 part. These results suggest that BIT has an improving effect on the impaired learning through the effects on memory registration and retrieval.

• Journal of Powder Materials
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• v.17 no.1
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• pp.29-35
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• 2010

We produced cylindrical porous TiNi bodies by Self-propagating High-temperature Synthesis (SHS) process, varying the heating schedule prior to ignition of a loose preform compact made from (Ti+Ni) powder mixture. To investigate the effect of the heating schedule on the behaviour of combustion wave propagation and the structure of porous TiNi shape-memory alloy (SMA) body, change of temperature in the compact during SHS process was measured as a function of time and used for determining combustion temperature and combustion wave velocity. Microstructure of produced porous TiNi SMA body was observed and the results were discussed with the combustion characteristics. From the results it was concluded that the final average pore size could be controlled either by the combustion wave velocity or by the average temperature of the preform compact prior to ignition.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.2
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• pp.192-196
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• 2012

In the present study, we examined the effect of the aqueous extract of Rubus coreanus Miquel (RCM-Ex) on scopolamine-induced memory impairment in male ICR mice. Mice were fed the diet containing 100 mg/kg body weight/day of RCM-Ex for 4 weeks. To induce amnesia, scopolamine (an antagonist of muscarinic acetylcholine receptor, 1 mg/kg of body weight) was intraperitoneally injected into mice 30 min before starting the behavior tests. RCM-Ex reversed scopolamine-induced memory impairments in mice as evidence by the passive avoidance test and Morris water maze test. In addition, acetylcholineasterase activities were decreased in the brains of mice treated with RCM-Ex. These results suggest that RCM-Ex may be an effective agent for the prevention of the memory impairment induced by cholinergic dysfunction.

• The Journal of Pediatrics of Korean Medicine
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• v.13 no.1
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• pp.139-166
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• 1999

The purpose of this review is to determine oriental concept of intelligence and memory, and to minimize adverse effect during treatment of brain disease by western medicine. Intelligence is developed by interaction between genetic factor ane environmental factor in Western medicine, Wherease mental function is difined by 'Chilsin' or 'Ohsin', and brain which control intelligence and memory is define by part of heart in oriental medicine The conception that mind and body are sameone may show possibility of intelligence and memory enhancement, and it may be usefule to clinical application.