• Title/Summary/Keyword: Cognitive science

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Reality and Function of Representation (표상의 실재성과 가능성)

  • Hung-YulSo
    • Korean Journal of Cognitive Science
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    • v.2 no.2
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    • pp.205-220
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    • 1990
  • Material substance may exist in two different modes of reality:real as physcal objects that comprise material cause and formal cause, and real as function networks that comprise efficient cause and functional cause.Functional networks are real as a mode of material substance because their efficient cause is energy consuming.Neural functional network, in this sense, are different from neural networks.In the same way, mental functional networks are real, for they are energy consuming and they function as a network.Mental functional networks, in turn, may divide into non-lingustic functional networks and linguistic functional networks.And further distinctions among the different levels of mental functional networks will be specified, and hence their reality confirmed more specifically as the research in cognitive science advances.

Correlation between Crowding and Binocular Rivalry depending on eccentricity (과밀 효과와 양안 경합의 이심률별 상관관계)

  • Kim, Sang-Rae;Chong, Sang-Chul
    • Korean Journal of Cognitive Science
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    • v.21 no.2
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    • pp.233-251
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    • 2010
  • Crowding effect is the impairment of peripheral object identification due to nearby objects. Binocular rivalry is a phenomenon in which perception alternates between two different objects presented separately to each eye. The purpose of this study was to investigate the correlation between these two phenomena. We measured the magnitudes of visibility index of these two effects at 8 different locations of 3 different eccentricities (2, 5, and $10^{\circ}$). Significant positive correlation between the two measurements was found only near the fovea ($2^{\circ}$). Our study is the demonstration to show relationship between crowding and binocular rivalry.

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Clustering-Based Mobile Gateway Management in Integrated CRAHN-Cloud Network

  • Hou, Ling;Wong, Angus K.Y.;Yeung, Alan K.H.;Choy, Steven S.O.
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.7
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    • pp.2960-2976
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    • 2018
  • The limited storage and computing capacity hinder the development of cognitive radio ad hoc networks (CRAHNs). To solve the problem, a new paradigm of cloud-based CRAHN has been proposed, in which a CRAHN will make use of the computation and storage resources of the cloud. This paper envisions an integrated CRAHN-cloud network architecture. In this architecture, some cognitive radio users (CUs) who satisfy the required metrics could perform as mobile gateway candidates to connect other ordinary CUs with the cloud. These mobile gateway candidates are dynamically clustered according to different related metrics. Cluster head and time-to-live value are determined in each cluster. In this paper, the gateway advertisement and discovery issues are first addressed to propose a hybrid gateway discovery mechanism. After that, a QoS-based gateway selection algorithm is proposed for each CU to select the optimal gateway. Simulations are carried out to evaluate the performance of the overall scheme, which incorporates the proposed clustering and gateway selection algorithms. The results show that the proposed scheme can achieve about 11% higher average throughput, 10% lower end-to-end delay, and 8% lower packet drop fractions compared with the existing scheme.

Resource Allocation with Proportional Rate In Cognitive Wireless Network: An Immune Clonal Optimization Scheme

  • Chai, Zheng-Yi;Zhang, De-Xian;Zhu, Si-Feng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.6 no.5
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    • pp.1286-1302
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    • 2012
  • In this paper, the resource allocation problem with proportional fairness rate in cognitive OFDM-based wireless network is studied. It aims to maximize the total system throughput subject to constraints that include total transmit power for secondary users, maximum tolerable interferences of primary users, bit error rate, and proportional fairness rate among secondary users. It is a nonlinear optimization problem, for which obtaining the optimal solution is known to be NP-hard. An efficient bio-inspired suboptimal algorithm called immune clonal optimization is proposed to solve the resource allocation problem in two steps. That is, subcarriers are firstly allocated to secondary users assuming equal power assignment and then the power allocation is performed with an improved immune clonal algorithm. Suitable immune operators such as matrix encoding and adaptive mutation are designed for resource allocation problem. Simulation results show that the proposed algorithm achieves near-optimal throughput and more satisfying proportional fairness rate among secondary users with lower computational complexity.

Cognitive Biases and Their Effects on Information Behaviour of Graduate Students in Their Research Projects

  • Behimehr, Sara;Jamali, Hamid R.
    • Journal of Information Science Theory and Practice
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    • v.8 no.2
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    • pp.18-31
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    • 2020
  • Cognitive biases can influence human information behaviour and decisions made in information behaviour and use. This study aims to identify the biases involved in some aspects of information behaviour and the role they play in information behaviour and use. Twenty-five semi-structured face-to-face interviews were conducted in an exploratory qualitative study with graduate (MA and PhD) students who were at the stage of their dissertation/thesis research. Eisenberg & Berkowitz Big6TM Skills for Information Literacy was adopted as a framework for interviews and the analysis was done using grounded theory coding method. The findings revealed the presence of twenty-eight biases in different stages of information behaviour, including availability bias (affects the preference for information seeking strategies), attentional bias (leads to biased attention to some information), anchoring effect (persuades users to anchor in special parts of information), confirmation bias (increases the tendency to use information that supports one's beliefs), and choice-supportive bias (results in confidence in information seeking processes). All stages of information seeking were influenced by some biases. Biases might result in a lack of clarity in defining the information needs, failure in looking for the right information, misinterpretation of information, and might also influence the way information is presented.

Ultradian Rhythms in the Hypothalamic Arcuate Nucleus Kisspeptin Neurons and Developmental Processes

  • Kim, Doyeon;Choe, Han Kyoung;Kim, Kyungjin
    • Molecules and Cells
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    • v.43 no.7
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    • pp.600-606
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    • 2020
  • Numerous physiological processes in nature have multiple oscillations within 24 h, that is, ultradian rhythms. Compared to the circadian rhythm, which has a period of approximately one day, these short oscillations range from seconds to hours, and the mechanisms underlying ultradian rhythms remain largely unknown. This review aims to explore and emphasize the implications of ultradian rhythms and their underlying regulations. Reproduction and developmental processes show ultradian rhythms, and these physiological systems can be regulated by short biological rhythms. Specifically, we recently uncovered synchronized calcium oscillations in the organotypic culture of hypothalamic arcuate nucleus (ARN) kisspeptin neurons that regulate reproduction. Synchronized calcium oscillations were dependent on voltage-gated ion channel-mediated action potentials and were repressed by chemogenetic inhibition, suggesting that the network within the ARN and between the kisspeptin population mediates the oscillation. This minireview describes that ultradian rhythms are a general theme that underlies biological features, with special reference to calcium oscillations in the hypothalamic ARN from a developmental perspective. We expect that more attention to these oscillations might provide insight into physiological or developmental mechanisms, since many oscillatory features in nature still remain to be explored.

Non Pharmacological Approaches in the Irritable Bowel Syndrome (과민성 장 증후군의 증상 경감을 위한 비약물적 접근 고찰)

  • Choe, Myoung-Ae;Kim, Keum-Soon;An, Gyeong-Ju;Chae, Young-Ran;Choi, Jung-An;Hong, Hae-Sook;Park, Mi-Jung;Lee, Kyung-Sook;Shin, Gi-Soo;Jeong, Jae-Sim
    • Journal of Korean Biological Nursing Science
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    • v.7 no.2
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    • pp.49-57
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    • 2005
  • There have been many trials of clinical efficacy of multi component and single component treatments for irritable bowel syndrome(IBS). We reviewed effects of non phamacological treatments in the IBS. Though the efficacy of multi-component approaches was unclear, several results suggest that cognitive behavioral therapy was effective in improving gastrointestinal symptoms of IBS. As a single component, cognitive therapy and relaxation with or without biofeedback could improve the symptoms and psychological health of IBS patients. Yoga, meditation, self-help information and hypnotherapy could be applicable to IBS.

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Lexicon of Semantic-Polarity of Korean Adjectives for the Classification of On-line Opinion Documents (온라인 오피니언 문서 분류를 위한 한국어 형용사 의미 극성 사전)

  • Ahn, Ae-Lim;Shim, Seung-Hye;Nam, Jee-Sun
    • Annual Conference on Human and Language Technology
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    • 2010.10a
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    • pp.166-171
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    • 2010
  • 본 논문은 한국어 온라인 리뷰 문서의 오피니언 분류(Opinion Classification)에 있어 그 핵심 키워드가 형용사 (Adjective) 범주라는 점을 고려하여, 한국어 형용사를 <문맥에 의존하지 않는 절대 극성>과, <문맥에 의존하여 극성이 바뀌는 상대극성>으로 대분류한 뒤 그 각각의 의미 극성을 하위 분류하는 작업을 수행하였다. 기존의 연구에서 특징적인 오피니언 어휘 수십개에 의존하여 자동 분류를 시도하고자 하였던 문제점을 극복하기 위해서는 한국어 형용사 전체 범주에 대한 체계적인 극성 분류가 이루어져야 할 필요가 있으며, 여기서 특히 상세히 주목받지 못했던 상대 극성 어휘에 대한 본격적인 의미 분류가 요구된다. 본 연구에서 제시하는 형용사의 극성 분류는 기존의 이론 언어학적 형용사 의미 분류와 달리 온라인 오피니언 문서에서 도메인에 따라 나타나는 특징적 의미 유형을 결정하고, 이를 기준으로 온라인 오피니언 문서의 극성 판별에 효과적으로 적용할 수 있는 사전을 구축하였다는 점에서 의의를 가진다.

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The Influences of Cognitive Conflict, Situational Interest, and Learning Process Variables on Conceptual Change in Cognitive onflict Strategy with an Alternative Hypothesis (대안가설이 도입된 인지갈등 전략에서 인지갈등 및 상황흥미와 학습 과정 변인이 개념변화에 미치는 영향)

  • Kang, Hun-Sik;Choi, Sook-Yeong;Noh, Tae-Hee
    • Journal of the Korean Chemical Society
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    • v.51 no.3
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    • pp.279-286
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    • 2007
  • In this study, we investigated the influences of cognitive conflict and situational interest induced by a discrepant event and an alternative hypothesis, attention and state learning strategies on conceptual change. A preconception test was administered to 486 seventh graders. They also completed the questionnaires of cognitive response and situational interest to a discrepant event before/after presenting an alternative hypothesis. After learning the concept of density with a CAI program as conceptual change intervention, the tests of attention, state learning strategies, and conceptual understanding were administered as posttests. Analyses of the results for 197 students having misconceptions about density revealed that post-cognitive conflict was significantly higher than pre-cognitive conflict. However, there was no statistically significant difference between the test scores of pre-situational interest and post-situational interest. Pre-cognitive conflict only exerted a direct effect on post-cognitive conflict, while post-cognitive conflict exerted a direct effect and Journal of the Korean Chemical Society an indirect effect via attention on conceptual understanding. Both pre- and post-situational interests were found to influence on conceptual understanding via attention. Attention had influences positively on deep learning strategy and negatively on surface learning strategy. There was a relatively small effect of state learning strategies on conceptual understanding.

A Systematic Review on the Association between Cognitive Function and Upper Extremity Function in the Elderly (노인의 인지기능과 상지기능의 관련성에 관한 체계적 고찰)

  • Moon, Mi-Sook;Jung, Min-Ye
    • Therapeutic Science for Rehabilitation
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    • v.5 no.2
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    • pp.23-33
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    • 2016
  • Objectives: The aim of this study was to investigate the association between cognitive function and upper extremity function in the elderly. The articles were analyzed based on patient, intervention, comparison, and outcome using the P.I.C.O. principle. Methods: We systematically examined papers from January, 2000 to November, 2015 published papers through the foreign journals which were Medline & Pubmed for three months. mainly used key words were elderly, dementia, Alzheimer's disease, Mild cognitive impairment, age-related, aging, cognitive, upper extremity function, hand function, hand-grip strength, grip force, complex motor function, bimanual, dexterity, UE performance, and coordination. Results: The number of discovered outcomes for association between cognitive function and upper extremity function in the elderly was 7; grip strength & sex are impact on manipulation object, 1. The results show that cognitive function is associated with upper extremity function in the elderly. Conclusion: This study is expected to help selecting intervention, assessment tools according to the individual's degree of cognitive level and upper extremity function. In future domestic research, variety assessment tools need to be used and more qualitative level experiment will be carried out.