• Journal of Communications and Networks
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• v.16 no.2
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• pp.146-154
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• 2014

This paper proposes a bandwidth-aware localized-routing algorithm that is capable of sensing the available spectrum bands within a two-hop neighboring for choosing the highly opportunistic routes. A mixed-integer linear programming (MILP) is utilized to formulate the optimization problem. Then, the proposed algorithm is used to determine the maximum bandwidth possible of link pairs via a bandwidth approximation process of relaxed variables. Thereby, the proposed algorithm can allow selected routes corresponding to maximum bandwidth possible between cognitive radio (CR) users through link pairs in cognitive radio networks. By comparing the solution values to previous works, simulation results demonstrate that the proposed algorithm can offer a closed-optimal solution for routing performance in cognitive radio networks. The contribution of this paper is achieved through approximately 50% throughput utilized in the network.

• Journal of Fisheries and Marine Sciences Education
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• v.21 no.2
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• pp.278-290
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• 2009

The purpose of this study is to investigate the relationship between learning skills and cognitive functions on elementary school students. In this study CAS and Learning Skills Test(LST) were administered with 3 to 6 grade, 60 students from 5 elementary schools. The data were analyzed according to Pearson's correlation and Stepwise Multiple Regression Analysis. The results are as follows. Firstly, girls and older students showed significantly higher ability than boys and younger students on the learning skills. And girls significantly outperformed boys on the planning function and attention function and on the simultaneous cognitive function was the other way round. Secondly, learning skills were explained 41% by two variables that the planning function and the successive function which are sub factors of the cognitive function. And then, planning and successive processing effected to self-management, attention and planning to test-taking skills, successive processing and attention to class-participation skills, and successive processing to information processing.

• Transactions on Control, Automation and Systems Engineering
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• v.1 no.1
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• pp.62-68
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• 1999

FCM(Fuzzy Cognitive Map) is proposed for representing causal reasoning. Its structure allows systematic causal reasoning through a forward inference. Authors have already proposed a diagnostic system based on FCM to utilized to identify the true origin of fault by on-line pattern diagnosis. In FCM based fault diagnosis, Temporal Associative Memories (TAM) recall of FCM is utilized to identify the true origin of fault by on-line pattern match where predicted pattern sequences obtained from TAM recall of fault FCM models are compared with actually observed ones. In engineering processes, the propagation delays are induced by the dynamics of processes and may vary with variables involved. However, disregarding such propagation delays in FCM-based fault diagnosis may lead to erroneous diagnostic results. To solve the problem, a concept of FTCM(Fuzzy Time Cognitive Map) is introduced into FCM-based fault diagnosis in this work. Expecially, translation method of FTCM makes it possible to diagnose the fault for some discrete time. Simulation studies through two-tank system is carried out to verify the effectiveness of the proposed diagnostic scheme.

• Korean Journal of Social Welfare
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• v.48
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• pp.243-270
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• 2002

The purpose of this study was to test the effectiveness of cognitive-behavioral therapy to prevent relapse of substance abuse. A total of 8 substance abusing adult clients participated in the program. All the clients were charged with substance use at the time of implementing the program. Two master's level social workers operated the program, which was implemented in a probation office in Seoul. This study included Beliefs about substance use, abstinence self-efficacy, and coping skills as dependent variables in order to investigate the effectiveness. Cognitive-behavioral therapy emphasizes the enhancement of these cognitive and behavioral skills to prevent relapse of substance use. Research hypotheses were partially supported. That is, clients participated in the program had more negative attitude toward substance use and had more effective problem-focused coping skills. Although a research hypothesis of the enhancement of clients' self efficacy was not supported, their mean scores at the final post test were lower than scores at pretest. This study suggests that more studies be needed to in order to confirm the effectiveness of cognitive-behavioral therapy with substance abusing clients.

• Research in Mathematical Education
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• v.6 no.2
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• pp.171-182
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• 2002

Students approach mathematical problem solving in fundamentally different ways, particularly problems requiring conceptual understanding and complicated strategies such as mathematical word problems. The main objective of this study is to compare students' performance with different cognitive styles (Field-dependent vs. Field-independent) on mathematics problem solving, particularly, in word problems. A sample of 180 school girls (13-years-old) were tested on the Witkin's cognitive style (Group Embedded Figures Test) and two mathematics exams. Results obtained support the hypothesis that students with field-independent cognitive style achieved much better results than Field-dependent ones in word problems. The implications of these results on teaching and setting problems emphasizes that word problems and cognitive predictor variables (Field-dependent/Field- independent) could be challenging and rather distinctive factors on the part of school learners.

• The Mathematical Education
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• v.46 no.4
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• pp.483-492
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• 2007

The purpose of this study was to investigate the relation between the cognitive processes and the mathematical achievement of the 4th grade students. And according to the several studies, there were significant relation between cognitive processes and achievement. Based on the PASS(Planning-Attention-Simultaneous-Successive Processes) Model presented by Das and Naglieri, four cognitive process variables were selected. The results of this study as follows. First, there was not significant relation between attention and mathematical achievement. Second, there was significant relation between planning and mathematical achievement. Third, there was significant relation between simultaneous/successive processes and mathematical achievement. Fourth, the students who got higher scores in the two types (simultaneous/successive)of information processing had more mathematical achievement. Specially, the students who got higher scores in the type of simultaneous information processing had higher scores in mathematical achievement. These results indicated that planning and simultaneous information processing had influence on the mathematical achievement.

• Research in Mathematical Education
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• v.15 no.4
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• pp.373-386
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• 2011

Students approach mathematical problem solving in fundamentally different ways, particularly problems requiring conceptual understanding and complicated strategies. The main objective of this study is to compare students' performance with different thinking styles (Field-dependent vs. Field independent) in mathematical problem solving. A sample of 242 high school males and females (17-18 years old) were tested based on the Witkin's cognitive style (Group Embedded Figure Test) and by a math exam designed in accordance with Bloom's Taxonomy of cognitive level. The results obtained indicated that the effect of field dependency on student's mathematical performance was significant. Moreover, field-independent (FI) students showed more effective performance than field-dependent (FD) ones in math tasks. Male students with FI styles achieved higher results compared to female students with FD cognitive style. Moreover, FI students experienced few difficulties than FD students in Bloom's Cognitive Levels. The implications of these results emphasize that cognitive predictor variables (FI vs. FD) could be challenging and rather distinctive factor for students' achievement.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.26 no.1
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• pp.10-24
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• 2018

This paper tried to analyze the response of air traffic controller(ATC) against abnormal situations using survey based on cognitive strategies suggested by Malakis et al.(2010). The survey designed to empirically analyze the effect of the cognitive strategy factors on organizational effectiveness. The main purpose of this research was as follows: First, it was analyzed both the individual-scale and team-scale factors which constructed the cognitive strategy against abnormal situations. Secondly, how seriously impact the ATC's cognitive strategies on their organizational effectiveness. The organizational effectiveness was divided into such two latent variables as job absorption and job satisfaction. According to the a analysis, it was proven that premeditated act of ATC had a positive significant effect on team-scale cognitive strategies such as teamwork, communication and error management. Moreover, it was found out the team-scale cognitive strategies had also a positive significant effect on job absorption. On the other hands, individual-scale cognitive strategies had no or negative effect on job absorption. Job absorption was proven to have a significant effect on job satisfaction of ATC.

• Journal of Science of Art and Design
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• v.13 no.1
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• pp.23-37
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• 2008

Recently, there are getting popular form generation-related design methodologies and scientific discourses about the nature of nature in the environmental design. The necessity of visual perception and cognitive research is growing in this respect. Accordingly, this study was designed to discuss environmental design and cognition in the ecological perspective. This study was intended to study the structural factors of cognitive ecological space. This study focused on the systematic principle of new environmental design based on cognitive ecological approaches and what kinds of design effects this design principle has on the human being in the long nm. The results are as follows. First, the results suggests that fractal pattern should be an alternative to design cognitive ecological space and new paradigm of architecture is based on the nature of nature and human sensibility. Accordingly, they have proposed that fractal design is more empirical and environment-friendly than rational linear design. Second, this study classified the variables of cognitive ecological space into nature, tradition, preference judgement, aesthetic value, and schema. Accordingly, such features as symbol, tradition, and nature restricted by modernistic ideology should be added to new paradigm-based environmental design. Third, accordingly, this study stresses that cognitive ecological environmental design doesn't include buildings of modernism and deconstruction and is based on new science of complexity.

• Clinical Psychopharmacology and Neuroscience
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• v.16 no.4
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• pp.461-468
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• 2018

Objective: Cognitive disturbance is one of the major symptoms of depression and may be improved by treatment with antidepressants. This study aimed to investigate the predictors of cognitive improvement in patients with major depressive disorder (MDD) who were taking antidepressants. Methods: This study included 86 patients with MDD who completed 12 weeks of antidepressant monotherapy. Cognitive symptoms were assessed using the Perceived Deficits Questionnaire-Korean version (PDQ-K), which addresses four domains of cognitive functioning (attention/concentration, retrospective memory, prospective memory, and organization/planning) and was administered at study entry and at the 12-week end point. A variety of demographic, clinical, and treatment-related variables were evaluated as predictors of changes in total and domain scores. Results: All PDQ-K domains showed significant improvement after 12 weeks of antidepressant treatment. More severe initial depressive symptoms, fewer sick-leave days at study entry, and reduced use of concomitant anxiolytics/hypnotics during treatment were significantly associated with greater cognitive improvement. Conclusion: Cognitive symptoms are more responsive to antidepressant treatment in patients with severe MDD. Reduced use of anxiolytics and hypnotics could improve the cognitive functioning of patients with MDD taking antidepressants.