• Journal of the Korean Crystal Growth and Crystal Technology
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• v.12 no.6
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• pp.304-310
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• 2002

Novel charge trap type memory devices with reoxidized oxynitride gate dielectrics made by NO annealing and reoxidation process of initial oxide on substrate have been fabricated using 0.35 $\mu \textrm{m}$ retrograde twin well CMOS process. The feasibility for application as NVSM memory device and characteristics of traps have been investigated. For the fabrication of gate dielectric, initial oxide layer was grown by wet oxidation at $800^{\circ}C$ and it was reoxidized by wet oxidation at $800^{\circ}C$ after NO annealing to form the nitride layer for charge trap region for 30 minutes at $850^{\circ}C$. The programming conditions are possible in 11 V, 500 $\mu \textrm{s}$ for program and -13 V, 1ms for erase operation. The maximum memory window is 2.28 V. The retention is over 20 years in program state and about 28 hours in erase state, and the endurance is over $3 \times 10^3$P/E cycles. The lateral distributions of interface trap density and memory trap density have been determined by the single junction charge pumping technique. The maximum interface trap density and memory trap density are $4.5 \times 10^{10} \textrm{cm}^2$ and $3.7\times 10^{18}/\textrm{cm}^3$ respectively. After $10^3$ P/E cycles, interlace trap density increases to $2.3\times 10^{12} \textrm{cm}^2$ but memory charges decreases.

• Science of Emotion and Sensibility
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• v.21 no.2
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• pp.137-144
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• 2018

The study figured out the operational conditions of a two-way movement actuator made of one-way shape memory alloy (OWSMA) for versatile ventilation intelligent garments. To develop a low-power actuator that consumes energy only when a garment changes its form such as opening and closing, multiple channels of OWSMA were used, and optimum diameter of the wires was examined. For the switch device, optimum voltage application unit time was determined. Optimum diameter of OWSMA wire was determined by applying 3.7V to the pre-determined candidate diameters, which demonstrated two-way operation in previous studies. In order to evaluate the optimum voltage application time, the internal diameter of the actuator was measured while increasing and decreasing by 50 ms from the unit time of voltage application. Delay time under two-way operation of the actuator was measured to minimize interference caused by heat between channels. Power of 3.7V was applied to OWSMA for assessment of optimal time, and the whole process from heating to cooling was video-recorded with a thermal image camera to determine the point of time at which the temperature of OWSMA wire dropped below the phase transformation temperature. The results showed that $0.4{\Phi}$ was the most suitable diameter, and the optimum unit time of voltage applied to open and close the actuator was 4100ms. It was also shown that the delay time should be more than 1.8 seconds between two-way operations of the actuator.

• Korean Journal of Cognitive Science
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• v.18 no.2
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• pp.113-138
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• 2007

The effects of schema on accurate and false memories of items in a scene were investigated in two experiments: Recognition of items in a scene was tested immediately in Experiment 1 and three days later in Experiment 2. In both experiments, the following three variables were manipulated: Exposure time (250ms or 10000ms), picture mode (completed pictures or scrambled pictures), and manipulation mode (missing item or substituted item). Experiment 1 had yielded three important results: First, although accurate memory for presented items got increased when the exposure time was longer, false memory of the critical lures was not changed. Second, false memory of critical lures in the missing condition, where there was not any conflict between verbatim information and gist information, was higher than that of the substituted condition, where verbatim information of the item that replaced the lure was in conflict with the gist information. Third, accurate memory for atypical items in the substituted rendition, which had replaced the critical lures and in conflict with the schema, was higher than that in the missing condition. In Experiment 2, recognition test were administered 72 hours after the participants saw the picture. The three effects mentioned in Experiment 1 had disappeared in Experiment 2. The results of Experiment 2 might be due to the selective weakening of verbatim information compared to the persistence of the gist (or schematic) information. The results of Experiments 1 and 2 showed that false memory of critical lures is more persistent than the accurate memory of non-critical information. Theoretical implications of the results were considered in terms of the function of the verbatim and gist information.

• Korean Journal of Cognitive Science
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• v.27 no.1
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• pp.101-127
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• 2016

The present study was conducted to examine the effect of meta-cognitive strategy and transfer appropriate processing(TAP) on prospective memory performance. In two experiments, encoding strategy for PM target words was manipulated by instructions. Participants who were assigned to meta strategic condition were engaged to rate task difficulty(EOL) in addition to predict their own performance(JOL), while participants in cognitive strategy condition were to remember target words by pleasantness ratings and sentence generation. In experiment1 and experiment 2, all participants in both conditions performed not only TAP ongoing task but also TIP ongoing task. Results revealed the benefit of meta cognition and transfer appropriate processing on PM performance. Furthermore, the benefit of TAP was diminished in cognitive strategy condition. There were no-costs on judgement tasks across conditions. The findings suggest that meta-cognition allows to sustain PM targets and intention without regard to cognitive resource.

• Korean Journal of Cognitive Science
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• v.19 no.3
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• pp.311-330
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• 2008

The effect of spatial attention gradually decreases as a function of the distance between the locus of attention and a target. According to this hypothesis, we tested the spatial-effect profile of visual attention when it operates on perception and memory. Experiment 1 measured accuracy of discriminating the color of a simultaneously masked target after presenting a pre-cue to either at the target location or away from the target (perception-intensive task). Experiment 2 measured accuracy of recognizing the color of several items at and around the pre-cued location (memory-intensive task). In the perception-intensive condition, the accuracy gradually dropped as the distance between the cue and target location increases. However, in the memory-intensive condition, subjects remembered only the item at the cued location. This suggests spatial attention in a memory-intensive process would operate on object-based representations. Experiment 2 showed the object-based effect observed in Experiment 1 can be also present in perception under a special circumstance. The results indicate that spatial attention can operate on object-based representations in a memory-intensive process whereas it flexibly can operate either on location-based or object-based representations in a perception-intensive process.

• Korean Journal of Cognitive Science
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• v.6 no.2
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• pp.97-116
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• 1995

This study was conducted to investigate how syntaction and pragmatic constraints influence the sentential representation and memory accessibility. In order to seperate the syntactic constraints from the pragmatic constraint from the pragmatic constraints,the syntactic role of constituent in the sentence (subject or object) and the order of mention(first or second) were manipulted.After each sentence was presented by RSVP procedure,the probe recognition time was measured to investigate memory accessibility.In Experiment 1,in which SOA interval was 255ms,it was found that the subject of a sentece were more accessible than the object and participants first in a sentence were more accessible than participants mentioned later.However, in Experiment 2,in which SOA interval was 1540ms,it was found that participants mentioned first in a sentence were more accessible than participants mentioned later while there was no significant difference between the subject and object of a sentece.These results suggest that the syntactic and pragmatic constraints have an independent effect on the initial senential representation at the early stage of constructing representation,but as time passes only the pragmatic constraints influence sentential representation.These results also support a theoretical position which assumes that sentential representation is constructed through the process of convergent statisfaction of multiple constraints.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.3
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• pp.875-888
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• 2013

The researches have recently progressed toward the use of the superelastic shape memory alloys (SMAs) to develop new smart control systems that reduce permanent deformation occurring due to severe earthquake events and that automatically recover original configuration. The superelastic SMA materials are unique metallic alloys that can return to undeformed shape without additional heat treatments only after the removal of applied loads. Once the superelastic SMA materials are thus installed at the place where large deformations are likely to intensively occur, the structural system can make the best use of recentering capabilities. Therefore, this study is intended to propose new buckling-restrained braced frames (BRBFs) with superelastic SMA bracing systems. In order to verify the performance of such bracing systems, 6-story braced frame buildings were designed in accordance with the current design specifications and then nonlinear dynamic analyses were performed at 2D frame model by using seismic hazard ground motions. Based on the analysis results, BRBFs with innovative SMA bracing systems are compared to those with conventional steel bracing systems in terms of peak and residual inter-story drifts. Finally, the analysis results show that new SMA bracing systems are very effective to reduce the residual inter-story drifts.

• Science of Emotion and Sensibility
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• v.22 no.4
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• pp.31-44
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• 2019

This study intended to investigate the effects of the subtitle location on the decreased working memory abilities caused by aging. A junior group (average age: 26, SD: 3.06, N=27) and a senior group (average age: 61.69, SD=4.18, N=26) participated in this study and they all performed N-back tasks which measured the working memory ability of the participants and video subtitle recognition tasks that assessed the most effectively recognized subtitle locations in the video. The results of the N-back task revealed slower response times and low accuracy rates in the senior group in comparison to the junior group, suggesting lower working memory abilities in the senior group vis-à-vis the junior group. The deterioration of working memory due to aging also negatively influenced the 'left-bottom' subtitle location in the video subtitle recognition task and positively influenced the 'left-center' location of the screen. The deterioration of working memory ability did not affect other subtitle locations. By examining the positive or negative effects of the deterioration of working memory ability as a function of age on subtitle locations, the present study suggests that the selection of suitable subtitle locations taking into account the ages of video viewers would cause information to be more effectively displayed on screen.

• Journal of the Korea Convergence Society
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• v.6 no.2
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• pp.13-18
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• 2015

The purpose of the study is to investigate the predisposing factors of posttraumatic stress disorder (PTSD) in fire fighters in Korea and to suggest the program development and solution to the critical incident stress management (CISM) in the future. PTSD is characterized by invasion, withdrawal, negative change of cognition and mood, and hypersensitivity. Trauma memory includes explicit memory and implicit memory. The explicit memory is conscious, cognitive, and descriptive and is controlled by hippocampus. The data of explicit memory have inhibitive and narrative language structure. The implicit memory is inconscious, emotional, and remembered by the body. The implicit memory is controlled by amygdala and has inexpressive language structure. The deletion of implicit memory is the key point to trauma treatment. Critical incident stress management (CISM) is the approach for the solution of PTSD. In conclusion, the essential goal of CISM is the psychological cessation of PTSD. This study tried to suggest the education program development of PTSD.

• Journal of Life Science
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• v.26 no.2
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• pp.234-240
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• 2016

The Y-maze is widely used to test working memory in behavioral science. For this purpose, spontaneous alternation behavior is monitored, and an increased percentage of spontaneous alternation is regarded as enhanced working memory. However, in some cases, the percentage of spontaneous alternation does not accurately reflect the extent of working memory in rodents. To complement the short-comings of this measure, we developed a new method to evaluate working memory on the Y-maze. This is done by defining all spontaneous alternation cases and P_i, the probability that the rodent achieved spontaneous alternation from each alternation case. After all P_i-values acquired in each animal are summarized, the result is considered as entropy. To validate the new analytical method, mice were raised under either control or an enriched environmental condition for 10 weeks, and working memory behavior on the Y-maze was monitored. The results showed that the new analytical method successfully reproduced significance. In addition, the new method turned out to be more accurate than measurement of the percentage of spontaneous alternation, meaning that, to get higher entropy, alternation should be recorded in all arms and directions. Together, these data indicate that the new analytical method is a useful supplement to the method that compares the percentage of spontaneous alternation, and thus is a good tool with which to evaluate working memory in rodents.