• Carbon letters
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• v.15 no.3
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• pp.151-161
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• 2014

Exceptional progress has been made with chemical vapor deposition (CVD) of graphene in the past few years. Not only has good monolayer growth of graphene been achieved, but large-area synthesis of graphene sheets has been successful too. However, the polycrystalline nature of CVD graphene is hampering further progress as graphene property degrades due to presence of grain boundaries. This review will cover factors that affect nucleation of graphene and how other scientists sought to obtain large graphene domains. In addition, the limitation of the current research trend will be touched upon as well.

• Advanced Composite Materials
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• v.18 no.4
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• pp.297-314
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• 2009

A design method is proposed to optimize the stacking sequence of laminated composite plates for desired vibration characteristics. The objective functions are the natural frequencies of the laminated plates, and three types of optimization problems are studied where the fundamental frequency and the difference of two adjacent frequencies are maximized, and the difference between the target and actual frequencies is minimized. The design variables are a set of discrete values of fiber orientation angles with prescribed increment in the layers of the plates. The four lamination parameters are used to describe the bending property of a symmetrically laminated plate, and are optimized by a gradient method in the first stage. A new technique is introduced in the second stage to convert from the optimum four lamination parameters into the stacking sequence that is composed of the optimum fiber orientation angles of all the layers. Plates are divided into sub-domains composed of the small number of layers and designed sequentially from outer domains. For each domain, the optimum angles are determined by minimizing the errors between the optimum lamination parameters obtained in the first step and the parameters for all possible discrete stacking sequence designs. It is shown in numerical examples that this design method can provide with accurate optimum solutions for the stacking sequence of vibrating composite plates with various boundary conditions.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 2001.01a
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• pp.400-409
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• 2001

In conceptual design of engineering devices, a designer decomposes a required function into sub-functions, so-called functional decomposition, using a kind of functional knowledge representing achievement relations among functions. However, such knowledge about functionality of engineering devices is usually left implicit because each designer possesses it. Even if such knowledge is found in documents, it is often scattered around technical domains and lacks consistency. Aiming at capturing such functional knowledge explicitly and sharing it in design teams, we discuss its systematic description based on functional ontologies which provide common concepts for its consistent and generic description. We propose a new concept named “was of achievement” as a key concept for capturing such functional knowledge. Categorization of typical representations of the knowledge and its organization as is-a hierarchies are also discussed. The generic concepts representing functionality of a device in the functional knowledge are provided by the functional concept ontology, which makes the functional knowledge consistent and applicable to other domains. We also discuss development of a design supporting system using the systematized knowledge, called a functional was server. It helps human designers redesign an existing engineering device by providing a wide range of alternative ways of achievement of the required function in a manner suitable for the viewpoint of each designer and then facilitates innovative design.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.18 no.6A
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• pp.75-83
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• 2008

In this paper, we design a user authentication method between domains when mobile node moves in AAA server based MIPv6 environment. Several papers proposed the user authentication method executing at AAA server in home domain via AAA server in visiting domain. In this paper we proposed the user authentication method using privilege certificates between domains.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1897-1902
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• 2008

The computer system is used in many application domains and any system error in these domains may either cause critical loss or threaten environment or human life. Though examples of these domains can be found in many areas, the system, which is used in domains for carrying passengers including rolling stocks in particular, is expected to show satisfactory operation all the time. The relay control logic, which is used in rolling stocks, is complex in hardware and occupies considerably large volume. Nevertheless, it has been used for a long time, to let the system safely operate even in the occurrence of an error in the computer system. However, the relay control logic circuit is so complex that the analysis of proper circuit operation and interlocking tends to be dependent only on the designer's experiences instead of being systematically performed. Especially, the analysis following a change, addition and deletion of a previous circuit according to the requirements from a source of demand is significantly limited. In this paper, the accuracy of relay control logic is verified by the use of properties of Petri Net model. In addition, how main circuit breaker (MCB) control circuit is modeled and analyzed by the design methodology is shown.

• Journal of People, Plants, and Environment
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• v.24 no.1
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• pp.75-84
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• 2021

Background and objective: This study was conducted to examine the effects of the theme-based garden book (photo book) making integration program on social skills and self-determination of college students with developmental disabilities. Methods: We analyzed the changes in social skills and self-determination of college students with developmental disabilities. The first step was defining the theme-based garden book (photo book) making integration program, which was done by focus group interviews (FGI) comprised of specialists in the industry and academia. The second step was carrying out 8 sessions of the program. The third step was examining the effects of the program on social skills and self-determination of college students with developmental disabilities. The participants of this study were 36 college students with developmental disabilities attending N University, and 17 students were in the experiment group and the other 19 in the control group. Results: The control group showed no statistically significant changes in the three sub-domains of social skills, while the experimental group showed statistically significant differences across all three sub-domains, such as cooperation(P < .05), assertion(P < .05), and self-control(P < .05). The experimental group, that participated in the program showed statistically significant differences across all four sub-domains of self-determination skills, such as behavior (P < .05), cognition(P < .05), school support(P < .05) and home support(P < .05). This proved that the theme-based garden book (photo book) making program contributed to bringing positive effects to self-determination and social skills. Conclusion: These results suggest that the theme-based garden book (photo book) making integration program could improve self-determination and social skills of college students with developmental disabilities. These positive changes are related to the high level of interest in theme-based garden design programs among college students with developmental disabilities, and thus these programs can be used effectively to improve social adjustment.

• Steel and Composite Structures
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• v.35 no.5
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• pp.701-715
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• 2020

Steel storage racks are lightweight structures, made of thin-walled cold-formed members, whose behaviour is remarkably influenced by local, distortional and overall buckling phenomena, frequently mutually combined. In addition, the need of an easy and rapid erection and reconfiguration of the skeleton frame usually entails the presence of regular perforations along the length of the vertical elements (uprights). Holes and slots strongly influence their behaviour, whose prediction is however of paramount importance to guarantee an efficient design and a safe use of racks. This paper focuses on the behaviour of isolated uprights subjected to both axial load and bending moments, differing for the cross-section geometry and for the regular perforation systems. According to the European standards for routine design, four alternatives to evaluate the bending moment-axial load resisting domains are shortly discussed and critically compared in terms of member load carrying capacity.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.366-372
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• 2018

The purpose of this study was to investigate the effects of educational evaluation with the application of flipped learning on undergraduate students' self-directed learning ability (cognitive domains, motive domains, conductive domains) and cognitive learning competency (knowledge and thought, creation, problem solving). An educational evaluation class, which applied flipped learning designed on the basis of pre-class, in-class, and post-class, was taught to 57 undergraduate students for twelve of the sixteen weeks of a semester. It was held each week on Thursdays for two (Ed- I don't understand 'for two'). The study results showed that, applying the flipped learning educational education class for undergraduate students improved self-directed learning ability (motivation domains, behavior domains) and cognitive learning competence (higher order thinking, metacognition, creativity tendency, problem-solving process). This study provides meaningful suggestions on exploring instructional design and effective teaching and learning methods applied to flipped learning.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.12B
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• pp.1489-1497
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• 2011

As a way for defending against cyber security threats, there has been a research on cybersecurity information exchange between security management domains in order to raise security performance of the whole network. One of the hottest issues in exchanging cybersecurity information between security management domains is that the requirements of those domains on information sharing are different with each other because each is autonomous domain. This paper proposes a mechanism for effective cybersecurity Information exchange between independent security management domains, which can satisfy their requirements on information sharing through sharing policy and sharing policy control protocol, proposed in this paper. In this paper we have developed an integrated security control system that supports the proposed mechanism. Through the system the performance of the proposed mechanism is measured and evaluated.

• Women's Health Nursing
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• v.13 no.1
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• pp.51-59
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• 2007

Purpose: This research was aimed to explore the major subjects and research theme and to classify characteristics of the key words in recent Korean Journal of Women Health Nursing. Methods: With survey design, whole 103 published papers during 2003-2006 were analyzed with structured analysis form; research subjects, research methodology, data analysis, and key words of the published papers were classified and extracted. Various theme was founded and classified to 9 domains. Results: Most of the research subjects were women. Eighty-eight percent of papers conducted quantitative research; 83% chose convenience sampling and 69% used survey design, while experimental design was 29%. Key words were categorized 9 domains: demographic, health related concept, health behavior(intervention), sex-related, life event, disease, et al. Among 9 domains, health related concept, especially psycho-social topics such as depression, anxiety, stress were mostly studied and then physiologic topics such as labor pain, fatigue, and menstrual symptoms. Conclusion: Most of the subjects were women and the most common domain studied was health related concepts in Korean Journal of Women Health Nursing. And key words and topics were on women's health issues. We can conclude that Korean Journal of Women Health Nursing has published by her own philosophy.