• Journal of Communications and Networks
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• v.16 no.1
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• pp.10-17
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• 2014

This work investigates two important performance metrics of underlay cooperative cognitive radio (CR) networks: Interference cumulative distribution function of licensed users and outage probability of unlicensed users. These metrics are thoroughly analyzed in realistic operating conditions such as imperfect fading channel information and strict transmit power constraint, which satisfies interference power constraint and maximum transmit power constraint, over Nakagami-m fading channels. Novel closed-form expressions are derived and subsequently validated extensively through comparisons with respective results from computer simulations. The proposed expressions are rather long but straightforward to handle both analytically and numerically since they are expressed in terms of well known built-in functions. In addition, the offered results provide the following technical insights: i) Channel information imperfection degrades considerably the performance of both unlicensed network in terms of OP and licensed network in terms of interference levels; ii) underlay cooperative CR networks experience the outage saturation phenomenon; iii) the probability that the interference power constraint is satisfied is relatively low and depends significantly on the corresponding fading severity conditions as well as the channel estimation quality; iv) there exists a critical performance trade-off between unlicensed and licensed networks.

• Journal of Information Science Theory and Practice
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• v.5 no.3
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• pp.15-30
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• 2017

In some situations, you need information in order to solve a problem that has occurred. In information science, user needs are often described through very specific examples rather than through a classification of situation types in which information needs occur. Furthermore, information science often describes general human needs, typically with a reference to Maslow's classification of needs (1954), instead of actual information needs. Lexicography has also focused on information needs, but has developed a more abstract classification of types of information needs, though (until more recent research into lexicographical functions) with a particular interest in linguistic uncertainties and the lack of knowledge and skills in relation to one or several languages. In this article, we suggest a classification of information needs in which a tripartition has been made according to the different types of situations: communicative needs, cognitive needs, and operative needs. This is a classification that is relevant and useful in general in our modern information society and therefore also relevant for information science, including lexicography.

• Journal of the Ergonomics Society of Korea
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• v.30 no.4
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• pp.451-458
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• 2011

Objective: This study is to develop a design and evaluation guide to the ergonomic design of the farm working convenient equipments in order for the elderly to use them easily and safely. Background: The aging population has already increased in farm villages. But due to the usage of the farm working equipments that did not reflect the characteristics and functional changes of aging, accidents and patients with disease are increasing. Method: The study investigated the functional changes and physical, cognitive, and sensuous characteristics of the aged. By determining the criteria for classification of the convenient equipments by crop, and by finding out the items necessary for the ergonomic design, a guide to this study is proposed. Results: It is obvious that the physical, cognitive and sensuous functions change as the aging process continues. Therefore, for the design and evaluation of Control Panel, Control Lever, Frame Size, Shape, and Equipment Weight that are the necessary items for the ergonomic approach for the farm working equipments, such characteristics have to be reflected. Conclusion: Through this study, a guide to the design and evaluation of convenient equipments for the farm works that reflected the aging characteristics and functional changes has been proposed. Application: The result of this study is to expect not only designers but also related specialists to make the best use of it.

• Korean Journal of Cognitive Science
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• v.11 no.1
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• pp.9-24
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• 2000

This paper analyzes the distribution and classification of unrealized arguments of a predicate often called zero pronouns. in spoken Korean. Based on the transcript of a one-hour-Iong dialogue. recorded from public radio stations. I present the statistical data on argument ellipsis in Korean with respect to the frequency of zero ronouns as well as the nature of their antecedents. I go further to review some of the previous efforts to identify the discourse- theoretic functions of zero-pronouns in the framework of Centering Theory. and propose that the zero-pronouns in spoken Korean be divided into center-insensitive vs. center-sensitive classes. I also point out a couple of language-particular idiosyncrasies found in Korean, such as morpho-syntactic elements and encyclopaedic knowledge. that interact with center management in on-going discourse and often lead to difficulties in applying the centering rules and constraints to Korean.

• Korean Journal of Cognitive Science
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• v.10 no.1
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• pp.45-55
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• 1999

This paper argues that the basic modes of spatial cognition can be best identified in terms of argument/participant location, and shows that natural language uses‘simple’types of semantic denotations to encode spatial cognition, and further notes that spatial expressions should be interpreted not as locating an event/state as a whole but as locating arguments/participants of the event. The ways of locating events/states are identified in terms of argument orientation(AO), Which indicates semantic patterns of linkiarticipant location. and shows that natural langrage uses ng locatives to specific arguments. Four patterns of argument orientation described here reveal substantial modes of spatial cognition. and the AO patterns are mostly determined by the semantic classes of English verbs combining with locative expressions, i.e., by the event type of the predicate. As for the denotational constraint of locatives, the paper concludes that semantic denotations of locative PPs are restricted to the intersecting functions mapping relations to relations.

• Journal of the Korean Institute of Landscape Architecture
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• v.33 no.4 s.111
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• pp.45-70
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• 2005

The purpose of this study is to overview foreign trends in the study of the landscape ecology through new framework of landscape ecological studies and to suggest possibility and limitation of introduction of landscape ecology studies in Korea. Because of historical reasons rooted in different disciplines, landscape ecology of the present time is not unified at all. Therefore, landscape ecology should be understood in an integrative manner accommodating different views and various aspects of landscape(NOOS, GEOS, BIOS). Facing the increasing environmental problems and the goal of sustainable landscape, the principle of a holistic approach complementarity and transdisciplinarity outlined in this paper (esp. connection physical-materials and cognitive system) might help to understand the characteristics of landscapes and landscape ecology. Important steps towards this direction are the landscape survey, diagnosis, the identification of landscape functions, the development of landscape evaluation models and landscape planning system. Recently there have been a few landscape ecological researches in Korea, which tells there have been strong needs to solve practical landscape problems caused by the rapid socioeconomic growth for several decades. However, almost of this studies are focused on cognitive and visual aspects of landscapes defined boundaries of disciplines. But for more holistic approach complementarity and transdisciplinarity in landscape ecological studies, many other aspects such as the consideration of geoecological and bioecologocal variables, preperation of ecological basic data(mapping) and the development of landscape planning as a tool for practical application should be integrated into the whole landscape system.

• Journal of muscle and joint health
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• v.27 no.2
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• pp.81-93
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• 2020

Purpose: We developed and tested the effects of a care program for dementia patients among community- dwelling older adult men. Methods: This study used a non-equivalent control group pre-and post-test design. To verify the effectiveness of the care program for dementia patients, 26 community dwelling older adult men participated in this study. We used multiple intervention strategies including improving understanding of dementia through education, activities for dementia prevention, and promoting psychological change. In particular, based on the current understanding of the care of the men older adults, we used strategies to promote motivation and reinforce strengths. Results: After completing the 6-week intervention program, when compared with the control group, older adult men in the care program intervention group showed significant differences in scores for the following: cognitive functions (p=.035), attitude toward dementia (p=.026), preventive behavior (p=.007), geriatric depression (p=.013), caring confidence (p=.018), and self-esteem (p=.013). Conclusion: These results indicate that the care program for dementia patients has positive effects on increasing their cognitive function, attitude toward dementia, preventive behavior, caring confidence, self-efficacy, and on decreasing depression rates in this population. Based on this, we can recommend this program to men caregivers for the improved care of dementia in community centers.

• Biomolecules & Therapeutics
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• v.22 no.5
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• pp.467-473
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• 2014

The purpose of this study is to investigate the memory enhancing effect and underlying molecular mechanism of arabinoxylan (AX), a major component of dietary fiber in wheat against scopolamine (SCO)-induced amnesia in Sprague-Dawley (SD) rats. Diverse behavior tests including Y-maze, Morris water maze, and passive avoidance tests were performed to measure cognitive functions. SCO significantly decreased the spontaneous alterations in Y-maze test and step-through latency in passive avoidance test, whereas increased time spent to find the hidden platform in Morris water maze test compared with the sham control group. In contrast, oral administration of AX (25 mg/kg and 50 mg/kg) effectively reversed the SCO-induced cognitive impairments in SD rats. Furthermore, AX treatment up-regulated the expression of brain-derived neurotrophic factor (BDNF) in the cortex and hippocampus via promoting activation of cAMP response element binding protein (CREB). Therefore, our findings suggest that AX can improve SCO-induced learning and memory impairment possibly through activation of CREB and up-regulation of BDNF levels, thereby exhibiting a cognition-enhancing potential.

• Korean Journal of Cognitive Science
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• v.11 no.3_4
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• pp.23-32
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• 2000

The distinction between main structure and side structure in discourse which was central to narrative studies has lacked an adequate. formal definition. This study supports the contention that there exists a hierarchical structure between discourse units constituting main structures, substructures, and side structures. The aim of this study is twofold: (j) to present an adequate. formal definition that provides a general identification criterion for distinguishing main structure from substructure and side structure proposed by Kuppevelt, and (jj) to propose conceptual relations representing hierarchical structures in discourse based on Sowa's Conceptual Structure Theory. The proposed conceptual relations which represent hierarchy and pragmatic relations of discourse segments are: DIGR (digression). T-SHFT (topic shift), and FRAM (frame). This s study shows pragmatic functions can be incorporated within CST in a systematic way.

• Journal of Information Processing Systems
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• v.8 no.1
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• pp.133-144
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• 2012

In order to make cognitive radio systems a practical technology to be deployed in real-world scenarios, the core Software Defined Radio (SDR) systems must meet the stringent requirements of the target application, especially in terms of performance and energy consumption for mobile platforms. In this paper we present a feasibility study of hardware acceleration as an energy-efficient implementation for SDR. We identified the amplifier function from the Software Communication Architecture (SCA) for hardware acceleration since it is one of the functions called for most frequently and it requires intensive floating-point computation. Then, we used the Virtex5 Field-Programmable Gate Array (FPGA) to perform a comparison between compiler floating-point support and the on-chip floating-point support. By enabling the on-chip floating-point unit (FPU), we obtained as high as a 2X speedup and 50% of the overall energy reduction. We achieved this with an increase of the power consumption by no more than 0.68%. This demonstrates the feasibility of the proposed approach.