• Title/Summary/Keyword: 기억 효과

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Fracture Characteristic of TiNi/A16061 Share Memory Alloy Composite at High Temperature using Acoustic Emission Technique (AE 기법을 이용한 TiNi/A16061 형상기억복합재료의 고온파괴특성평가)

  • Lee, Jin-Kyung;Park, Young-Choul;Kang, Dong-Hyun;Park, Dong-Sung;Lee, Kyu-Chang
    • Proceedings of the KSME Conference
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    • 2001.06a
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    • pp.72-77
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    • 2001
  • Tensile residual stress happen by difference of coefficients of thermal expansion between fiber and matrix is one of the serious problems in metal matrix composite(MMC). In this study, TiNi fiber was used to solve the tensile residual stress as the reinforced material. TiNi fiber improves the tensile strength of composite by occurring compressive residual stress in matrix using shape memory effect of it. Pre-strain was added to generate compressive residual stress inside TiNi/A16061 composite. It was also evaluated the effect of compressive residual stress corresponding to pre-strains variation. AE technique was used to clarify the microscopic damage behavior at high temperature and the effect of pre-strain difference of TiNi/A16061 shape memory alloy composite.

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Seismic Protection for Multiple Span Continuous Steel Bridges using Shape Memory Alloy-Restrainer-Dampers (형상기억합금을 이용한 다경간 연속 강교량의 지진보호)

  • Park, Eunsoo;Kim, Haksoo
    • Journal of the Earthquake Engineering Society of Korea
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    • v.8 no.1
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    • pp.77-86
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    • 2004
  • This paper introduces a shape memory alloy-restrainer-damper(SMA-RD) to protect multiple span continuous steel bridges from seismic loads. The type of bridges has only one fixed bearing condition on a pier and expansion bearings are located on the other piers and abutments. Due to this state and a big mass of the deck, these bridges are usually very vulnerable to column's damage on which fixed bearings are located and large deformation of abutments in passive action. Two types of SMA-RDs are developed, and their effect is inspected for protecting the bridges through seismic analyses. Conventional steel restrainer cables are also used to reduce the seismic vulnerability of the bridge and the results are compared to those of the SMA-RDs.

Design of Tool Clamping Device Based on a Shape Memory Alloy (형상기억합금 기반 공구 클램핑 장치 설계)

  • Lee, Dong-Ju;Shin, Woo-Cheol;Park, Hyung-Wook;Ro, Seung-Kook;Park, Jong-Kweon;Chung, Jun-Mo
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.17 no.5
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    • pp.70-75
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    • 2008
  • This paper describes a tool-clamping/unclamping mechanism for application of a micro-spindle. The mechanism is based on one-way shape memory effect and interference-fit. The corresponding mathematical models and a few considerable design parameters are mentioned in this paper. Especially, necessary conditions for the clamping and unclamping operation are investigated through finite element analysis. The analysis results show that the differences between the diametral deformations of the tool holder in high temperature and that in low temperature are increased according to amounts of the interference. Thus the less interference between the tool-holder and the ring, the less tolerance to allow the clamping and unclamping operation because the inner diameter of the tool holder in high temperature should be smaller than the diameter of the tool shank, and that in low temperature should be larger than the diameter of the tool shank. In addition, the design for maximization of clamping force are investigated based on finite element analysis. The results show that the more amounts of the interference, the more clamping force. As the result, the interference should be considered as a important factor to maximize the tool clamping force.

The Effect of Fermented Codonopsis lanceolata on the Memory Impairment of Mice (발효더덕 추출물이 흰쥐의 인지능 회복에 미치는 효과)

  • Park, Sung-Jin;Park, Dong-Sik;Kim, Seung-Seop;He, Xinlong;Ahn, Ju-Hee;Yoon, Won-Byung;Lee, Hyeon-Yong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.11
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    • pp.1691-1694
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    • 2010
  • In the present study, we assessed whether the extracts of Codonopsis lanceolata and fermented C. lanceolata posses the cognition-enhancing effect in rats with impaired learning and memory by scopolamine treatment (1 mg/kg, i.p.), an antagonist of muscarinic acetylcholine (ACh) receptor. The fermented C. lanceolata extract (333, 667 mg/kg) significantly reversed the scopolamine-induced cognitive impairments in the passive avoidance test (p<0.05). Moreover, fermented C. lanceolata extract (333 mg/kg) also improved escape latencies in training trials of Morris water maze test (p<0.05). The water extract of fermented C. lanceolata showed significant anti-amnestic and cognitive-enhancing activities related to the memory processes, and these activities were parallel to treatment duration and dependent of the learning models.

A Study on in Influence on the Memory-Based Judgement and Purchase Intention upon Temporal Distance and Prior Kowledge in Preannouncing Strategy (시간적 거리와 사전지식에 따른 프리어나운싱 전략이 기억에 근거한 판단과 구매의도에 미치는 효과)

  • Han, Kwang-Seok
    • Management & Information Systems Review
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    • v.33 no.1
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    • pp.99-118
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    • 2014
  • This study is a product launch strategy Preannouncing companies associated with temporal distance( in the near future/ distant future) and prior knowledge level(high knowledge/ low knowledge), the memory - based judgments(Global product judgment/ Discrete product judgment) and the purchase intention appears, the difference between the empirical verification of what was discriminatory. The study, first, Preannouncing main effect of temporal distance on judgments remember the difference between the purchase intention and consistent global product judgment is more discrete product judgment were higher awareness, purchase intention is higher. Second, Preannouncing high level of product knowledge in global product judgment showed that compared to discrete product judgment. In addition, low levels of knowledge than a discrete product judgment that global product judgment and purchase intention shown that a high level of consumer knowledge through systematic information processing and the road leads to higher purchase attitude. Third, Preannouncing according to the temporal distance and level of knowledge about the interaction effect results in the near future in terms of the high level of knowledge consumers global product judgment was higher than the discrete product judgment. On the other hand, a low level of knowledge of conditions in the distant future, consumers are more discrete product judgment recognized global product judgment showed that high.

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Effect of Supplementation with Docosahexaenoic Acid from Gestation to Adulthood on Spatial Learning Performance in Rat (임신기부터 성장기 동안 Docosahexaenoic Acid 보충에 의한 흰쥐의 공간기억력 개선 효과)

  • Lim, Sun-Young
    • Journal of Life Science
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    • v.17 no.10
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    • pp.1400-1405
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    • 2007
  • The effect of supplementation with docosahexaenoic acid into n-3 fatty acid deficient diet on improvement of loaming related brain function was investigated. On the second day after conception, Sprague Dawley strain dams were subjected to a diet containing either n-3 fatty acid deficient (Def) or n-3 fatty acid deficient + docosahexaenoic acid (Def+DHA). After weaning, male pups were fed on the same diet of their respective dams until adulthood. Motor activity and Morris water maze tests were measured at 10 weeks old. In motor activity test, there were no statistically significant differences in moving time and moving distance between the Def and Def+DHA diet groups. The n-3 fatty acid deficient with DHA (Def+DHA) group exhibited a shorter escape latency, swimming time and swimming distance (P<0.05) compared to the n-3 fatty acid deficient group (Def) but there was no difference in resting time and swimming speed between the experimental diet groups. In memory retention trial, the number of crossing of the platform position (region A) was significantly greater than those of other regions for the Def+DHA group. However, the Def group swam randomly without preference for the provisions platform location, indicating poorer memory retention. From those results, supplementation with DHA into the n-3 fatty acid deficient diet improved the spatial loaming ability in rats as assessed by Morris water maze test.

Development and Analysis of a Walking Game 'Paldokangsan3' Using Kinect (키넥트를 이용한 걷기게임 '팔도강산3' 개발 및 효과성 연구)

  • Kim, KyungSik;Lee, YoonJung;Oh, SeongSuk
    • Journal of Korea Game Society
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    • v.14 no.1
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    • pp.49-58
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    • 2014
  • We have developed a serious game for the elderly named 'Paldokangsan3' as a next version of 'Paldokangsan2' which was a walking game with memorization in shopping streets using controllers of hand buttons and foot boards with PC developed in 2012. The interface of had buttons and food boards were changed into the interface of motion capture with the aid of Kinect. The expected effects are improvement of memorization, improvement of concentration ability to find out items in the vision, improvement of vitality through physical walking actions, as well as improvement of mental health through entertainment activities of game play. We have tested 25 volunteers of more than 65 years old in Cheonan city community center for the elderly for 2 weeks. We got the result that the game play was showing positive effectiveness on memorization, physical exercise and self-esteem in mental health area of the elderly.

Unfolding Nested Loops of Functional Languages for Multithreaded Architectures (다중스레드 구조를 위한 함수형 언어의 중첩루프 펼침)

  • 하상호
    • Journal of KIISE:Software and Applications
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    • v.29 no.11
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    • pp.826-836
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    • 2002
  • We need an enormous amount of memories for name spaces as well as additional processors if we are to effectively exploit a massively parallelism in nested loops of functional languages such as Id. If there is no sufficient amount of memories enough to exploit that parallelism, the execution of programs can be aborted during the unfolding of loops. Additionally, if loops are overunfolded, compared with the number of processors available, the system performance can be degraded severely due to the overhead of loop unfolding. This paper suggests and analyzes an algorithm which can be used to effectively unfold nested loops of functional languages on multithreaded architectures. This algorithm has a feature to unfold a given nested loop safely and near optimally, considering the system resources of processors and memories available when the loop is to be unfolded.

A Study on the Cognitive Rehabilitation Project of the Elderly with Moderate Memory Dementia (기억학교 경증치매노인의 인지재활사업에 관한 연구)

  • Suh, Kyung-Do;Choi, In-Kyu
    • Journal of Digital Convergence
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    • v.15 no.5
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    • pp.517-522
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    • 2017
  • The purpose of this study was to develop a cognitive rehabilitation program based on the cognitive activities of the elderly with mild dementia using the weekly care facilities in Daegu city memory and to provide useful welfare services for the elderly with mild dementia. In Korea, there is not much development of community-based integrated intervention program for demented patients who are still in the present situation. The results of this study suggest that the cognitive rehabilitation program for the elderly with mild dementia is suitable to be applied as a group in the case of community based protective editorials and may be a basis for management of mild dementia patients. It seems that there may be differences in the appropriate intervention methods and effects. Therefore, it is expected that the individualized customized strategy will maximize the effect. Therefore, more specific and individualized nursing intervention program should be concurrently developed.

Effects of the Integrative Cognitive Training Program on Elderly Cognitive Function (통합적 인지훈련프로그램의 노인 인지기능에 미치는 효과)

  • Kong, Eun Suk;Kim, Eun-Ju
    • The Journal of the Korea Contents Association
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    • v.14 no.9
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    • pp.332-342
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    • 2014
  • The purpose of this study is to investigate the Effects of the Integrative Cognitive Training Program on Cognitive Function of the community elderly. Nonequivalent control group pretest-posttest design was used. 28 subjects were assigned to each of the group. 24 sessions of the integrative Cognitive Training Program were applied to the experimental group from September to December. The program was provided twice per week for 12weeks, total 24 sessons to the experimental group. Cognition scale for older adults(CSOA) was used to measure cognitive function of the groups before and after the Intervention. The score of Cognition Scale for Older Adults was significantly increased in experimental group than in control group(p< .05). The results of the study that Integrative Cognitive Training Program can be vey useful to improve the cognitive ability for the community elderly.