• KSII Transactions on Internet and Information Systems (TIIS)
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• 제7권12호
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• pp.3003-3017
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• 2013

In this paper, we investigate the outage performance of a cognitive relay network. We consider mutual interference in an independent, non-identically distributed Nakagmai-m fading environment. We first derive the close-form outage probability expression, which provides an efficient means to evaluate the effects of several parameters. This allows us to study the impact of several parameters on the network's performance. We then derive the asymptotic expression and reveal that the diversity order is strictly determined by the fading severity of the cognitive system. It is not affected by the primary network. Moreover, the primary network only affects the coding gain of the cognitive system. Finally, Monte Carlo simulations are provided, which corroborate the analytical results.

• ETRI Journal
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• 제33권6호
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• pp.961-964
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• 2011

The cognitive ultra-wideband (UWB) network detects interfering narrowband systems and adapts its configuration accordingly. An inherently adaptive and flexible candidate for cognitive UWB transmission is the wavelet packet multicarrier modulation (WPMCM). In this letter, we use an enhanced forward consecutive mean excision thresholding algorithm to tackle the noise uncertainty in the wavelet-based sensing of WPMCM systems, and mathematical analysis is performed for primary user channel fading. As a benchmark, we compare the proposed system with a conventional fast Fourier transformation-based system, and performance investigation proves significant improvements when primary and secondary links are subjected to multipath fading and noise.

• 한국시스템다이내믹스연구
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• 제10권4호
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• pp.39-51
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• 2009

In this paper, we constructed a cognitive map of President Lee of Korea on the policy vision of green growth. This cognitive map is characterized by a scarcity of feedback loops and a strong emphasis on the positive loops. These characteristics can be understood by the fact that the green growth policy is to overcome the limits to growth coming from negative feedback loops. As a conclusion, we proposed a negative feedback loop approach to the green growth policy vision, which might minimize the side effects of positive loops.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2003년도 Proceeding
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• pp.10-15
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• 2003

In computer graphics, most animations of characters have been created using the traditional and often highly labor intensive key-framing technique. Recently, character animation is demanded increasingly automated techniques for animation according to interaction with the user or environment of the user. In this paper, we will propose a new method which can animate characters automatical/y with user interactions. The character's behavior is determined as a result of understanding the emotional condition of the user. Psychology and cognitive AI provide some ideas about how to approach this problem. Our study is based mostly on the theories of Ortony, Clore and Collins, which were designed to be implemented computationally. In our system, we can make 22 emotion types and some more behavior features and we apply to some characters.

• 노인간호학회지
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• 제20권sup1호
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• pp.154-159
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• 2018

Purpose: There is a need for artificial intelligence which nurtures human intelligence as the prevalence of dementia and collapse of intelligence of human beings has become a social problem. Purpose of this study is to develop intervention technologies for maintaining cognitive health of older adults. Methods: The method named the Coimagination Method (CM) was proposed and has been developed in order to achieve goal. Conversation assistive technologies have been developed and tested based on the method. Results: The state of the art of the group conversation support system, and regular series of group conversation sessions for full-years with insights for healthy older adults are described in detail. Participatory approach has been applied to the design process for simultaneous research and implementation of the service. Both participants and practitioners have been maintaining their cognitive health for independent living. Conclusion: Findings imply that there exist potentially preventive types of dementia and intervention should be applicable for such types. Ways of thinking and living are gently intervened through understanding of personal values and broadening minds, which lead to improved quality of life.

• International Journal of Computer Science & Network Security
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• 제21권4호
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• pp.223-228
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• 2021

As a consequence of sudden outbreak of COVID-19 pandemic worldwide, educational institutes around the globe are forced to switch from traditional learning systems to e-learning systems. This has led to a variety of technology-driven pedagogies in e-teaching as well as e-learning. In order to take the best advantage, an appropriate understanding of the cognitive capability is of prime importance. This paper presents an intelligent cognitive maturity recognition system for confidence-based e-learning. We gather the data from actual test environment by involving a number of students and academicians to act as experts. Then a Genetic Programming based simulation and modeling is applied to generate a generalized classifier in the form of a mathematical expression. The simulation is derived towards an optimal space by carefully designed fitness function and assigning a range to each of the class labels. Experimental results validate that the proposed method yields comparative and superior results which makes it feasible to be used in real world scenarios.

• 대한통합의학회지
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• 제9권4호
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• pp.49-58
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• 2021

Purpose : This study investigates the effects of the application of traditional occupational therapy and the korean computerized cognition training system on the cognitive function and performance of daily activities of stroke patients with cognitive impairment. Methods : From inpatients referred for rehabilitation treatment at L Rehabilitation Hospital located in Busan, 20 patients diagnosed with stroke from April 05. 2021 to May 02. 2021 (study period) were selected, They were divided into two, an experimental group consisting of 10 subjects who underwent a computerized cognitive rehabilitation program and traditional occupational therapy in combination and a control group of 10 subjects who underwent traditional occupational therapy alone. In order to measure the cognitive function of the subjects before the intervention, two assessment tests were conducted: a Neurobehavioral Cognitive Status Examination (NCSE), which evaluates stroke-related cognitive ability, and a Functional Independence Measure (FIM) test, which evaluates life activities. Then, both groups received a total of 20 training sessions at 30 minutes per session, five times a week for four weeks. Results : A statistically significant difference was found in cognitive function between before and after the cognitive training for both the experimental group and the control group. For the FIM scores, statistically significant differences were observed after intervention in the categories of handling personal matters and social cognition, and in the total score. The average scores of the remaining items also improved. Conclusion : The results of this study showed that both the computerized cognition rehabilitation program and the traditional occupational therapy had a positive effect on the improvement of cognitive function in stroke patients.

• 한국엔터테인먼트산업학회논문지
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• 제13권8호
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• pp.603-610
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• 2019

본 연구는 휴대용 전산화 인지훈련 시스템이 경도 인지손상이 있는 뇌졸중 환자의 시지각에 미치는 효과를 알고자 하였다. 재활병원에 입원 중인 경도인지손상이 있는 12명의 뇌졸중 환자가 본 연구에 참여하였다. 모든 대상자들은 실험군과 대조군으로 6명씩 할당되었다. 모든 대상자들은 실험군 또는 대조군의 훈련을 하루 30분, 주 5회, 4주 동안 수행하였다. 실험군은 휴대용 전산화 인지훈련 시스템을 실시하였으며, 대조군은 보편적인 인지훈련을 수행하였다. 시지각을 측정하기 위하여, MVPT-3(Motor-Free Visual Perception-3)을 측정하였다. 연구 결과, 두 군은 중재 전과 후로 MVPT-3 total score에서 유의한 향상을 보였다(p<.05). 두 군 간 변화량 비교에서 실험군은 대조군보다 MVPT-3 total score와 visual short-term memory of sub-item of MVPT-3에서 유의하게 더 큰 향상을 보였다(p<.05). 이러한 결과는 휴대용 전산화 인지훈련 시스템이 경도인지손상이 있는 뇌졸중 환자의 시지각 능력 향상에 긍정적인 효과를 이끌어 낼 수 있는 중재방법이 될 수 있음을 시사한다.

• 가정∙방문간호학회지
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• 제20권1호
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• pp.16-23
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• 2013

Purpose: The purpose of this study was to analyze the relationship between cognitive function, self-esteem, and depression among patients in long-term care hospitals. Methods: The study participants were 159 patients from 2 long-term care hospitals in Kyungki province. Data were collected from January 2 to February 5, 2013, by conducting across-sectional descriptive survey using a structured questionnaire administered by researchers. Results: Cognitive function and depression were significantly different according to age, education level and marriage. Self-esteem was significantly different according to education level and economic status. Self-esteem was significantly positively correlated with cognitive function, which in contrast showed a significant negative correlation with depression. Among our subjects, those older than 80 years showed low cognitive function and those with low educational attainment showed high scores of depression. Conclusion: We conclude that, elderly patients in long-term care hospitals who have low educational attainment should be carefully monitored, especially by nurses, for cognitive function and depression. In addition, nurses should have constant communication with their patients. Moreover, long-term care hospitals should apply early detection of and a management system for cognitive impairment and depression among their patients.

• 한국인지과학회:학술대회논문집
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• 한국인지과학회 2006년도 춘계학술대회
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• pp.111-117
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• 2006