• Sleep Medicine and Psychophysiology
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• v.4 no.1
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• pp.1-14
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• 1997

This paper reviewed models to explain memory and neuropsychological tests to assess memory. Memory was explained in cognitive and neuroanatomical perspectives, Cognitive model describes memory as structure and process. In structure model, memory is divided into three systems: sensory memory, short-term memory(working memory), and long-term memory. In process model, there are broadly three categories of memory process: encoding, storage, and retrieval. Memory process work in memory structure. There are two prominent models of the neuroanatomy of memory, derived from the work of Mishkin and Appenzeller and that of Squire and Zola-Morgan. These two models are the most useful for the clinician in part because they take into account the connections between the limbic and frontal cortical regions. The major difference between the two models concerns the role of the amygdala in memory processess. Mishkin and his colleagues believe that the amygdala plays a significant role while Squire and his colleagues do not. The most popular and widely used tests of memory ability such as WMS-R, AVLT, CVLT, HVLT. RBMT, CFT, and BVRT-R, were reviewed.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.4
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• pp.569-577
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• 2009

Mobile information retrieval is an evolving branch of information retrieval that is centered on mobile and ubiquitous environments. In general, mobile devices are characterized by lightweight, low power, small memory, small display, limited input/output, low bandwidth, and so on. Some of these characteristics make it impossible to apply general information retrieval to mobile environments without any modification. In order to relieve this problem, we design and implement an information retrieval system for mobile devices like wireless phones, PDA and handheld devices. We use document summarization techniques to alleviate the limitation of small display and user profiles to retrieve the most proper documents for each individual user for personalized search. Futhermore we use meta-search to lighten some burdens visiting several portal sites. In this paper, we have implemented and demonstrated the proposed mobile information retrieval system on the domain of travel and received good evaluation from users subjectively.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.1
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• pp.254-261
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• 2005

The effects on memory and learning ability of the Korean herbal medicine, Xingyo-tang(XGT, 神交湯), which consists of Ginseng Radix(人蔘) 4 g, Liriopis Tuber(麥門冬) 40 g, Morindae Officinalis Radix(巴戟天) 40 g, Biotae Semen(柏子仁) 20 g, Dioscoreae Rhizoma(山藥) 40 g, Euryales Semen(?實) 20 g, Scrophulariae Radix(玄蔘) 40 g, Salviae Miltiorrhizae Radix(丹蔘) 12 g, Poria(茯神) 12 g, Cuscutae Semen(免絲子) 40 g, was investigated. The effects of XGT on learning and memory performance were examined in normal or memory impaired mice by using avoidance tests, Pentobarbital -induced sleep test, fear conditioning task, novel object recognition task, and water maze task. Hot water extract from XGT was used for the studies. Learning ability and memory are based on modifications of synaptic strength among neurons that are simultaneously active. Enhanced synaptic coincidence detection leads to better learning and memory. The XGT-treated (30 mg/100 g and 60 mg/100 g, p.o.) mice exhibit superior ability in learning and memorizing when performing various behavioral tasks. XGT did not affect the passive avoidance responses of normal mice in the step through and step down tests, the conditioned and unconditioned avoidance responses of normal mice in the shuttle box, lever press performance tests, and the ambulatory activity of normal mice in normal condition. In contrast, XGT produced ameliorating effects on the memory retrieval impairment induced by ethanol. XGT also improved the memory consolidation disability induced by electric convulsive shock (ECS). XGT extended the sleeping time induced by pentobarbital dose-dependently, suggesting its transquilizing or antianxiety action. These results suggest that XGT has an improving effect on the impaired learning through the effects on memory registration and retrieval.

• Journal of Korean Institute of Industrial Engineers
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• v.30 no.1
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• pp.17-26
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• 2004

In this study, the usability evaluation of a menu-structure was performed using spreading activation model with respect to human's memory retrieval. Spreading Activation Model is effectively used to understand the process of information retrieval, so it can be used as a theoretical background for modeling of the process of human's information retrieval. For spreading activation test (SAT), subjects were presented with 67 pairs of menu titles, which consist of a menu title in the high level menu item and a menu title for the next lower level menu item, from Korea University's web site. For performance tests, three scenarios were developed with longer reaction times and ambiguous associations found in the SAT to reflect the existing problems of the website. As a result, the SAT was found to bean effective tool to enhance the website usability because the SAT could bea substitute for the performance test with a high correlation $({\rho}=0.735,\;{\alpha}=0.05)$. After remaining menu titles with slow reaction times and ambiguous associations found in SAT, the website usability was significantly improved with faster reaction times and less ambiguous associations proven with smaller number of web-page visits. Therefore, the SAT could be used as a methodology to design and evaluate the user-centered menu structure related to human's association structure.

• Journal of the Korean Society of Radiology
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• v.6 no.3
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• pp.173-182
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• 2012

It was well known that working memory highly related with academic achievement. The aim of this study was to investigate the differences of brain activation which visually evoked working memory(encoding and retrieval) through functional Magnetic Resonance Imaging(fMRI) in Higher Academic Achievement Group(HAAG) and Lower Academic Achievement Group(LAAG) of college students. 20 assigned college students participated in fMRI studies. They underwent totally 210 seconds repeated paradigm. Stimulation paradigm composed with resting time and encoding and retrieval seeing the figures from the mirror with head coil. The brain activation maps and their quantification were analyzed by the statistical parametric mapping(SPM99) program from level of significance 95%. HAAG was more significantly higher than LAAG in bilateral prefrontal lobe(brodmann 46) associated with working memory, inferior parietal lobe associated with attention, and visual association area in encoding figures test. Right dosoprefrontal lobe(BA 44), right fusiform gyrus associated with decision of figure and, lingual gyrus were more activated in retrieval test with HAAG. On the other hand, LAAG was more significantly higher than HAAG in cingulate gyrus during encoding test. Thalamus, basal ganglia, cerebellum were more activated in retrieval test. Consequently, We could guess from these results HAAG more effectively executed than LAAG in visual working memory test.

• The KIPS Transactions:PartD
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• v.10D no.2
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• pp.187-194
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• 2003

Main Memory storage system can increase the performance of the system by assigning enough slack time to real-time transactions. Due to its high response time of main memory devices, main memory resident data management systems have been used for location management of personal mobile clients to cope with urgent location related operations. In this paper we have developed a multi-threaded main memory storage system as a core component of real-time retrieval system to handle a huge amount of readers and writers of main memory resident data. The storage system is implemented as an embedded component which is working with the help of a disk resident database system. It uses multi-threaded executions and utilizes latches for its concurrency control rather than complex locking method. It only saves most recent data on main memory and data synchronization is done only when disk resident database asks for update transactions. The system controls the number of read threads and update threads to guarantee the minimum requirements of real-time retrievals.

• Proceedings of the Ginseng society Conference
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• 1988.08a
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• pp.92-98
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• 1988

The present study was performed to find the effects of ginseng and its saponins. which is written in Chung Yao Ta Tsu Tien as anti-amnesia in its chief indication. on experimental amnesia in mice. In the step through test. ginsenoside $Rb_1\;(GRb_1)\;and\;GRg_1$ facilitated the registration of memory and antagonized the electroconvulsive shock (ECS)-induced inhibition of the retention of memory. Moreover. $GRg_1$ antagonized the EtOH-induced inhibition of the retrieval of memory. In the step down test. $GRb_1\;GRb_2\;and\;GRg_1$ antagonized the ECS-induced inhibition of the retention of memory. Moreover. $GRg_1$ antagonized the EtOH-induced inhibition of the retrieval of memory and facilitated the acquisition of short term memory. In the shuttle hox and lever press tests. they have no effects on acquisition and retrieval of memory. except $GRb_1\;GRb_1$ depressed the retrieval of conditioned avoidance response in the shuttle box test. After the end of four tests. the effects of these orally administered drugs on sedative. analgesic. antipyretic and anticonvulsant actions. and on spontaneous and exploratory movements were tested in doses of less than 500mg/kg. but they had none of these effects. Present study may indicate that $GRg_1$ had effects on the retrieval of memory and on the acquisition process of learning response. The recent research on the role of NGF for the survival. regeneration and regulation of brain in adult animals. indicated the importance of NGF on dementia and amnesia. During our research on the specificity of the neurite out growth induced by NGF. we found that the effect of NGF was potentiated by $GRb_1$ in organ cultures of chick embryonic dorsal root ganglia. Then. the effect of $GRb_1$ on neuronal cell survivalin cell culture system was studied. $GRb_1$ potentiated the NGF-mediated increase of neurofilaments in cell cultures of chick embryonic sensory and sympathetic neurons. NGF with $GRb_1$ also showed a tendency to increase the number of surviving neurons of rat embryonic cerebral cortex. NGF increased choline acetyl transferase activity in cell cultures of rat embryonic septum area neurons. but $GRb_1$ did not potentiate NGF activity in cell cultures of rat embryonic septum area neurons. Present study may indicate that $GRb_1$ plays an important role for the survival or regeneration of neurons in the brain.

• Proceedings of the Optical Society of Korea Conference
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• 1989.02a
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• pp.95-98
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• 1989

A new associative memory model using the SDF filter, one of the multiple filter for pattern recognition, is suggested in this paper. The SDF filter characteristics such as pattern classification lets the memorized patterns have orthogonal characteristics one another, so that enhances the associative memory's retrieval ability to the original pattern. The computer simulation shows that this new model is very useful in case that the imput patterns are seriously distorted and the cross-correlation between the memorized patterns is very high.

• Korean Journal of Cognitive Science
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• v.22 no.2
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• pp.145-172
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• 2011

Prospective memory (PM) is memory for activities to be performed in the future, such as remembering to purchase a piece of fruit on the way home or remembering to give someone a telephone message. Theoretically, PM retrieval can be accomplished either by controlled monitoring of intended action or by a more automatic process that spontaneously responds to the presence of intended event. The present study examined the effect of meta-cognitive awareness in PM retrieval process. In Experiment 1, we manipulated PM condition with a salient cue to stimulate participants' meta-cognitive awareness. Results showed the salient cue condition spontaneously triggered remembering to perform an intended action. In Experiment 2, we manipulated participants' meta-cognitive awareness about PM task difficulty and about the degree to which cognitive capacity is required to realize the PM task. Results showed that PM retrieval process varied with meta-cognitive awareness (i.e., more resources were allocated if the PM task was expected to be difficult). These results imply that participants' meta-cognitive awareness play an important role in PM retrieval process.

• Korean Journal of Biological Psychiatry
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• v.13 no.2
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• pp.117-120
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• 2006

Localized amnesia is characterized by a failure to recall events that occurred during a circumscribed period of time. Localized amnesia is the most common type of dissociative amnesia. It is assumed that this is a disorder of memory retrieval. Recent neuroimaing studies reported that posterior cingulate cortex may play a important role in memory(autobiographical) retrieval. The authors reported a case of localized amnesia with mass on left posterior cingulate cortex.