• Steel and Composite Structures
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• v.29 no.3
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• pp.319-332
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• 2018

This paper investigates the free vibration of geometrically imperfect functionally graded car-bon nanotube-reinforced composite (FG-CNTRC) beams that are integrated with two sur-face-bonded piezoelectric layers and subjected to a combined action of a uniform temperature rise, a constant actuator voltage and an in-plane force. The material properties of FG-CNTRCs are assumed to be temperature-dependent and vary continuously across the thick-ness. A generic imperfection function is employed to simulate various possible imperfections with different shapes and locations in the beam. The governing equations that account for the influence of initial geometric imperfection are derived based on the first-order shear deformation theory. The postbuckling configurations of FG-CNTRC hybrid beams are determined by the differential quadrature method combined with the modified Newton-Raphson technique, after which the fundamental frequencies of hybrid beams in the postbuckled state are obtained by a standard eigenvalue algorithm. The effects of CNT distribution pattern and volume fraction, geometric imperfection, thermo-electro-mechanical load, as well as boundary condition are examined in detail through parametric studies. The results show that the fundamental frequency of an imperfect beam is higher than that of its perfect counterpart. The influence of geometric imperfection tends to be much more pronounced around the critical buckling temperature.

• Journal of Information Science Theory and Practice
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• v.3 no.3
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• pp.75-80
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• 2015

Methods and Material: The PubMed database was used for retrieving data on 'cancer biology.' Articles were downloaded from the years 2000 to 2011. The articles were classified chronologically and transferred to a spreadsheet application for analysis of the data as per the objectives of the study. Statistical Method: To investigate the nature of growth of articles via exponential, linear, and logistics tests. Result: The year wise analysis of the growth of articles output shows that for the years 2000 to 2005 and later there is a sudden increase in output, during the years 2006 to 2007 and 2008 to 2011. The high productivity of articles during these years may be due to their significance in cancer biology literature, having received prominence in research. Conclusion: There is an obvious need for better compilations of statistics on numbers of publications in the years from 2000 to 2011 on various disciplines on a worldwide scale, for informed critical assessments of the amount of new knowledge contributed by these publications, and for enhancements and refinements of present Scientometric techniques (citation and publication counts), so that valid measures of knowledge growth may be obtained. Only then will Scientometrics be able to provide accurate, useful descriptions and predictions of knowledge growth.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.6
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• pp.1783-1796
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• 2015

The purpose of this study was to verify the formation of serious leisure experience for water sports mania using grounded theory method approach. Research participants were selected 6 water sports mania by reputational sampling method. Six participants who usually participated in water sports club were selected as research participants. The data for this study included participants' observation and in-depth interview. This study categorized the coding paradigm which was presented by using the findings derived from data as they were into casual condition, contextual element, central phenomenon, critical situation, mediative element, interaction, final result and core category to draw out the process of becoming a water sports mania and its significances. The results of were as follows. First, water sports mania recognized the environmentally safe pleasure and value. Second, water sports mania was in a race against myself. Third, water sports mania felt the social and environmental changes. Fourth, water sports mania was looking for alternative method. Fifth, water sports mania overcome physical limitations and liberation from fear of water. Lastly, water sports mania felt alive through the enthusiastic participation.

• Advances in nano research
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• v.8 no.3
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• pp.255-264
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• 2020

Buckling and post-buckling cases are often occurred in aorta artery because it affected by higher pressure. Also, its stability has a vital importance to humans and animals. The loss of stability in arteries may lead to arterial tortuosity and kinking. In this paper, post-buckling analysis of aorta artery is investigated under axial compression loads on the basis of Euler-Bernoulli beam theory by using finite element method. It is known that post-buckling problems are geometrically nonlinear problems. In the geometrically nonlinear model, the Von Karman nonlinear kinematic relationship is employed. Two types of support conditions for the aorta artery are considered. The considered non-linear problem is solved by using incremental displacement-based finite element method in conjunction with Newton-Raphson iteration method. The aorta artery is modeled as a cylindrical tube with different average diameters. In the numerical results, the effects of the geometry parameters of aorta artery on the post-buckling case are investigated in detail. Nonlinear deflections and critical buckling loads are obtained and discussed on the post-buckling case.

• Korean Institute of Interior Design Journal
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• v.25 no.1
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• pp.47-55
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• 2016

This article explores an extended sense of autonomy in contemporary architecture activated through the practice of fashion, by taking architect Rem Koolhaas' work Prada Epicenter in New York as a case. In doing so, it argues that throughout the work Koolhaas sets up a world in which the corporate and the individual are entangled together in complex ways. Instead of considering Prada Epicenter to be the exemplar illustrating that the global company-Prada-institutionalizes the designed commercial space in a top-down manner, this article claims that such a space imbricates a multiplicity of meaning that is generated at the intersections of the local and the global, the ordinary and the spectacular, and the individual and the institutional. In this respect French philosopher Gilles Lipovetsky's fashion theory works as a critical point: his claim that the ambivalence of fashion-both as corporate power and individual freedom-is a threshold encouraging us to better understand the operativity of late capitalism in daily life is extended to Koolhaas' case. In other words, Koolhaas' Prada Epicenter brings forth possibilities that the ostensibly technocratic and institutionalized space in fact works as a resillient field where senses of individual autonomy arise in the aid of corporative practice of branding.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.52 no.7
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• pp.421-428
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• 2003

After the cable is installed, many geometric factors, such as bowing types of the cable and the length difference of the cable between each minor section will cause the impedance unbalance between cables. The impedance unbalance will increase or decrease the sheath circulating currents, which are critical to human safety and sustaining the capabilities of electric power. Accordingly, in this paper, a new method is also proposed to reduce the sheath circulating currents and an reduction equipment according to the theory of the new method is developed. The reduction equipment is tested when the cable is on service. The test results show that it can reduce the sheath circulating currents by up to 97.8［%］. This confirms the validation of the new method and the reduction equipment, and assures the safe operation of the transmission cables. In order to illustrate the safe operation of the cable with new current reduction equipment at transient state due to lightning and single line-to-ground fault, extensive simulations have been made. Then the protection scheme of sheath circulating currents reduction equipment is proposed by adopting the new device of RDP(Reduction Device Protector).

• Journal of Families and Better Life
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• v.15 no.2
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• pp.185-200
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• 1997

In this study the meaning of well-being and welfare of home has been analyzed and a new direction in which home economics should advance has been suggested, This study not only would help the characteristics of home economics be properly understood and its displinary position take its own place but also a conceptual analysis which might be uncommon in the studies of learned circles of Korean home economics would be a basis for establishing the uniqueness of the discipline named by home economics. Based on the critical theory of Habermas it has been demonstrated that well-being and welfare of home have been emphasized unfairly in the physical and technical aspects and such a partial pursuit of positivism and purposive rationality of scientific technology has resulted in the situation that home would be gradually encroached and controlled by the social system pursuing purposive rationality. As an alternative to overcome this kind of problems communicative rationality that has em hasis on the process of intersubjective understanding and agreement has been focused. The meaning of well-being and welfare of home has been established through the classification of family life actions in to technical action practical action and emancipatory action, And the characteristics of them have been examined and ideal directionns of each element have been discussed.

• Journal of Environmental Impact Assessment
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• v.21 no.3
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• pp.391-407
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• 2012

The loss of connectivity and fragmentation of forest landscapes are seriously hindering dispersal of many forest-dwelling species, which may be critical for their viability and conservation by decreasing habitat area and increasing distance among habitats. For understanding their environmental impacts, numerous spatial models exist to measure landscape connectivity. However, general relationships between functional connectivity and landscape structure are lacking, there is a need to develop landscape metrics that more accurately measure landscape connectivity in whole landscape and individual patches. We reviewed functional and structural definition of landscape connectivity, explained their mathematical connotations, and applied representative 13 indices in 3 districts of Seoul having fragmented forest patches with tits, the threshold distance was applied 500m by considering the dispersal of tits. Results of correlation and principal component analysis showed that connectivity indices could be divided by measurement methods whether they contain the area attribute with distance or not. Betweenness centrality(BC), a representative index measuring distance and distribution among patches, appreciated highly stepping stone forest patches, and difference of probability of connectivity(dPC), an index measuring including area information, estimated integrated connectivity of patches. Therefore, for evaluating landscape connectivity, it is need to consider not only general information of a region and species' characteristics but also various measuring methods of landscape connectivity.

• Journal for History of Mathematics
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• v.19 no.1
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• pp.43-54
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• 2006

The purpose of this paper, followed by 'Nature$\cdot$Human, and Golden Section I ', is to study aesthetic consciousness, mentality model and body proportion of human, and the golden section applied to architecture and hand axe of stone age. In particular, handaxes of one million years ago have shown that they had critical competency to the basis of art and mathematics in the future. Furthermore, without pen, paper and ruler, the existence of mentality model made fundamental conversion of mathematics possible. Different sizes of handaxes were made by maintaining the equal golden section. This was the first example in relation to the principle mentioned in 'Stoicheia' by Euclid which was published hundred thousands of years later.

• Asia pacific journal of information systems
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• v.14 no.3
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• pp.23-55
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• 2004

Interests on Service Level Agreement(SLA), an immanence operating tool for managing the level of the information system service objectively and qualitatively, were raised among IT outsourcing service providers, outsourcers, and operating departments. Yet, only a few domestic conglomerates adopted the SLA, and exact usage of the SLA is currently unknown. Because of the importance of the SLA between a service recipient and a service provider, the agreement is treated with high confidentiality. This raised the problems to organizations which are considering the SLA but lack in the concrete guide line to internalize SLA management process. This study provides the process model of implementation for SLA by conducting multiple case research. The sampled companies are currently implementing the SLA over 1 year of usage period. Factors were used to provide the managerial contribution for implementing the SLA. To analyse the case samples, in-depth interview method was conducted for each sampled company. As a result, if SLA can be used as an immanence managerial tool and can be actively implemented, it will be an strategic tool for various decision making in IT management practice with long term relationship, better shared partnership, and continuous service improvement.