• Title/Summary/Keyword: Cognitive Science

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The Web Site Design Simulation Using Stratified Fuzzy Cognitive Map (계층화된 퍼지 인식도를 이용한 웹 사이트 디자인 시뮬레이션에 관한 연구)

  • 이건창;정남호;조형래
    • Journal of the Korean Operations Research and Management Science Society
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    • v.26 no.1
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    • pp.15-32
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    • 2001
  • It is well known that the web design is composed of several factors which are interacting with each other. However, the current approach to web design had been focused on modifying specific factors without considering its impact on other factors. In this sense, we propose more holistic approach to the web design by using fuzzy cognitive map. For this purpose, we form an illustrative fuzzy cognitive map for the web design which is based on the literature, and analyzed and impact of change in a specific factor on other factors. Especially, to improve the output analyzability, we suggested an advanced version of fuzzy cognitive map called stratified fuzzy cognitive map. After simulating the fuzzy cognitive map for web design, we could conclude that our approach is robust and effective compared to the traditional web design approach.

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DEVELOPMENT OF AN INTEGRATED DECISION SUPPORT SYSTEM TO AID COGNITIVE ACTIVITIES OF OPERATORS

  • Lee, Seung-Jun;Seong, Poong-Hyun
    • Nuclear Engineering and Technology
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    • v.39 no.6
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    • pp.703-716
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    • 2007
  • As digital and computer technologies have grown, human-machine interfaces (HMIs) have evolved. In safety-critical systems, especially in nuclear power plants (NPPs), HMIs are important for reducing operational costs, the number of necessary operators, and the probability of accident occurrence. Efforts have been made to improve main control room (MCR) interface design and to develop automated or decision support systems to ensure convenient operation and maintenance. In this paper, an integrated decision support system to aid operator cognitive processes is proposed for advanced MCRs of future NPPs. This work suggests the design concept of a decision support system which accounts for an operator's cognitive processes. The proposed system supports not only a particular task, but also the entire operation process based on a human cognitive process model. In this paper, the operator's operation processes are analyzed according to a human cognitive process model and appropriate support systems that support each cognitive process activity are suggested.

The Effect of Cognitive Rehabilitation Program Combined with Physical Exercise on Cognitive Function, Depression, and Sleep in Chronic Stroke Patients

  • Kim, SoHyun;Cho, SungHyoun
    • Physical Therapy Rehabilitation Science
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    • v.11 no.1
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    • pp.32-42
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    • 2022
  • Objective: This study was conducted to verify the effectiveness of a cognitive rehabilitation program consisting of physical exercises and mental activities for patients with chronic stroke with mild cognitive impairment (MCI). We aimed to investigate how this cognitive rehabilitation program affects patients' cognitive ability, depression, and sleep quality. Design: One group pretest-posttest design Methods: The study was conductedon 12 patients who participated in thecognitive rehabilitation complex exercise program for 16 weeks. The Korean version of the Montreal Cognitive Assessment (MoCA-K), Hamilton Depression Rating Scale (K-HDRS), and Pittsburgh Sleep Quality Index (PSQI) were used to evaluate the measured variables before and after study participation. The cognitive rehabilitation complex exercise program included 30 minutes of cognitive exercise and 30 minutes of Brill Exercise. The Wilcoxon signed-rank test was used to compare the variables before and after program participation. Cronbach's ɑ was used to assess the reliability of the test variables. Results: The post-program assessment showed a statistically significant increase in the MoCA-K score, which measures cognitive function (Z=-2.628, P=0.009). For depression ratings, there was a statistically significant decrease in the K-HDRS score (Z=-2.041, P=0.041). For sleep quality, although there was a numerical increase in the PSQI score, the difference was not statistically significant (Z=-0.702, P=0.483). The reliability test confirmed that all the individual test variables exhibited high reliability (cognitive function, 0.859; depression, 0.872; sleep, 0.822). Conclusions: We found that cognitive rehabilitation program used in this study had a positive effect on the cognitive function and depression in patients with chronic stroke with MCI.

A Novel Cooperative Spectrum Sensing Algorithm in Cognitive Radio Systems

  • Zheng, Xueqiang;Wang, Jinlong;Wu, Qihui;Shen, Liang
    • Journal of Communications and Networks
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    • v.11 no.2
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    • pp.115-121
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    • 2009
  • In cognitive radio (CR) systems, cognitive users can use the frequency bands when the primary users are not present. Hence, reliable detection of available spectrum is foundation of cognitive radio technology. To ensure unimpaired operation of primary users, cooperative spectrum sensing is needed. To reduce the network overhead of cooperative spectrum sensing, a novel cooperative spectrum sensing algorithm based on credibility is proposed. In particular, the close-form expressions for probability of detection and false-alarm are derived for the novel algorithm, and expression for the average overhead used for cooperation is given. The thresholds design method for the algorithm is also discussed. The conclusion is proved by computer simulations.

Optimal Strategies for Cooperative Spectrum Sensing in Multiple Cross-over Cognitive Radio Networks

  • Hu, Hang;Xu, Youyun;Liu, Zhiwen;Li, Ning;Zhang, Hang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.6 no.12
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    • pp.3061-3080
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    • 2012
  • To improve the sensing performance, cooperation among secondary users can be utilized to collect space diversity. In this paper, we focus on the optimization of cooperative spectrum sensing in which multiple cognitive users efficiently cooperate to achieve superior detection accuracy with minimum sensing error probability in multiple cross-over cognitive radio networks. The analysis focuses on two fusion strategies: soft information fusion and hard information fusion. Under soft information fusion, the optimal threshold of the energy detector is derived in both noncooperative single-user and cooperative multiuser sensing scenarios. Under hard information fusion, the optimal randomized rule and the optimal decision threshold are derived according to the rule of minimum sensing error (MSE). MSE rule shows better performance on improving the final false alarm and detection probability simultaneously. By simulations, our proposed strategy optimizes the sensing performance for each cognitive user which is randomly distributed in the multiple cross-over cognitive radio networks.

Performance and Limitations of a Korean Sentiment Lexicon Built on the English SentiWordNet (영어 SentiWordNet을 이용하여 구축한 한국어 감성어휘사전의 성능 평가와 한계 연구)

  • Shin, Donghyok;Kim, Sairom;Cho, Donghee;Nguyen, Minh Dieu;Park, Soongang;Eo, Keonjoo;Nam, Jeesun
    • 한국어정보학회:학술대회논문집
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    • 2016.10a
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    • pp.189-194
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    • 2016
  • 본 연구는 다국어 감성사전 및 감성주석 코퍼스 구축 프로젝트인 MUSE 프로젝트의 일환으로 한국어 감성사전을 구축하기 위해 대표적인 영어 감성사전인 SentiWordNet을 이용하여 한국어 감성사전을 구축하는 방법의 의의와 한계점을 검토하는 것을 목적으로 한다. 우선 영어 SentiWordNet의 117,659개의 어휘중에서 긍정/부정 0.5 스코어 이상의 어휘를 추출하여 구글 번역기를 이용해 자동 번역하는 작업을 실시하였다. 그 중에서 번역이 되지 않거나, 중복되는 경우를 제거하고, 언어학 전문가들의 수작업으로 분류해낸 결과 3,665개의 감성어휘를 획득할 수 있었다. 그러나 이마저도 병명이나 순수 감성어휘로 보기 어려운 사례들이 상당수 포함되어 있어 실제 이를 코퍼스에 적용하여 감성어휘를 자동 판별했을 때에 맛집 코퍼스에서의 재현율(recall)이 긍정과 부정에서 각각 47.4%, 37.7%, IT 코퍼스에서 각각 55.2%, 32.4%에 불과하였다. 이와 더불어 F-measure의 경우, 맛집 코퍼스에서는 긍정과 부정의 값이 각각 62.3%, 38.5%였고, IT 코퍼스에서는 각각 65.5%, 44.6%의 낮은 수치를 보여주고 있어, SentiWordNet 기반의 감성사전은 감성사전으로서의 역할을 수행하기에 충분하지 않은 것으로 나타났다. 이를 통해 한국어 감성사전을 구축할 때에는 한국어의 언어적 속성을 고려한 체계적인 접근이 필요함을 역설하고, 현재 한국어 전자사전 DECO에 기반을 두어 보완 확장중인 SELEX 감성사전에 대해 소개한다.

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A Development of Checklists on the Cognitive Conflict Process Model Application in Science Concept Learning (인지갈등을 통한 개념수업 절차 모형의 점검틀 고안)

  • Kwon, Nan-Joo;Kwon, Jae- Sool
    • Journal of The Korean Association For Science Education
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    • v.16 no.3
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    • pp.239-248
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    • 1996
  • Many science teaching models have been devised and published for the students' conceptual change by researchers. However, the science teachers have been confused with so many models to be used in teaching science. Since the models are composed of ambiguous statements, it seems to be difficult for the teachers to understand their characteristics and natures. Therefore, the models were difficult to be adopted in science instructions. In this study, the researcher developed two checklists which were devised especially for the teachers who apply the Cognitive Conflict Process Model (the Procedural Teaching Model using Cognitive Conflict Strategy) in Science Concept Instruction. One is for planning instructions using the model, the other is for examining or analysing them. Each of them consisted of 20 items and 33 items, respectively. Using these checklists, the Cognitive Conflict Process Model can be checked whether it was applied properly in actual instruction or not.

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A novel routing protocol for cognitive radio networks with cooperation process

  • Kim, Sunwoo;Pyeon, Dohoo;Jang, Ingook;Yoon, Hyunsoo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.11
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    • pp.3860-3875
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    • 2014
  • Cognitive radio networks (CRNs) are composed of mobile users who can use multiple spectrum bands for communication. CRNs allow unlicensed users (called cognitive users) to efficiently utilize unused licensed spectrums without interfering with communications of licensed users (called primary users). The main goals of CRNs are to mitigate spectrum saturation and to improve spectrum utilization. This paper introduces state-of-the-art routing protocols for CRNs and addresses some limitations of these protocols. To resolve the limitations, we suggest a new research direction for routing protocols in CRNs. We implement our protocol to compare with the existing routing protocols for multi-hop CRNs. Our protocol shows good performance compared to the existing routing protocols in terms of network performance and PU protection.

Analysis of Cognitive Styles across Visual Discrimination Tasks (시각적 구별 과제를 통한 인지양식의 분석)

  • Soo-Young Kim;Shin-Woong Hwan;Jee-Yun Cho;Young-Woo Sohn
    • Science of Emotion and Sensibility
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    • v.7 no.2
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    • pp.163-178
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    • 2004
  • The present study identified dimensions of cognitive styles that were concerned with individual differences in cognitive processes. The results provided support for Robertson's [36] theory of cognitive processes that are independent of task. An individual's first or initial cognitive strategy may be consistent across different tasks and therefore considered their style. However, an individual's cognitive style may change after interacting with the task during a number of trials, and lead to a strategy that is particular to the task.

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Informational Justice, Cognitive Trust, and Satisfaction: Purchasers' Perspective of Healthcare Distribution Market

  • LEE, Changjoon
    • Journal of Distribution Science
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    • v.19 no.2
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    • pp.5-14
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    • 2021
  • Purpose: We examined informational justice, cognitive trust, and satisfaction in healthcare distribution market and their associations within the physician-patient (provider-purchaser) relationship. Methodology: 253 valid survey samples collected from patients and used structural equation modelling for analysis. Findings: We postulated that (1) physicians' informational justice has a positive impact on patients' cognitive trust, (2) patients' cognitive trust has a positive impact on satisfaction, and (3) patients' perceived informational justice has a positive impact on satisfaction. Participants were 253 people who had visited a hospital in South Korea in the past year. Results confirmed that the presence of informational justice has a positive impact on patients' cognitive trust and satisfaction in the physician-patient relationship. Additionally, once cognitive trust was built, it positively influenced patients' satisfaction. We discussed the concept and the impacts of informational justice in light of our analyses regarding patients' perceived cognitive trust and their satisfaction in the physician-patient relationship. Implications: These results emphasize the importance of ethics in healthcare, particularly physicians' frankness and honesty when providing information to patients. Further, these findings present implications for physician education, as part of their training must involve building their patients' cognitive trust as a prerequisite for developing patient satisfaction.