• 대한화학회지
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• 제57권3호
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• pp.361-364
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• 2013

A modified synthetic approach to the synthesis of heterocyclic food mutagens, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PHIP) and 2-amino-1,6-dimethylimidazo[4,5-b]pyridine (DMIP) is reported. This route highlights an optimized palladium catalysed Buchwald cross-coupling of 2-halo-1-methyl-imidazo[4,5-b]pyridine with benzophenoneimine followed by acidic hydrolysis to yield compound 7. Using finely tailored conditions, Suzuki cross-coupling reactions with highly efficient catalytic systems were performed as the final step on 8 to introduce the aryl group and methyl group on the heterocyclic core.

• Steel and Composite Structures
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• 제10권5호
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• pp.415-428
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• 2010

Proper material constitutive models for concrete-filled tube (CFT) columns of circular cross section and subjected to pure bending moment are proposed. These material models are implemented into the Abaqus finite element program and verified against experimental data. It has been shown that the steel tube does not provide good confining effect to the concrete core when the CFT columns is subjected to pure bending moment. When the diameter-to-thickness ratio of the CFT columns is small, the behavior of the CFT column is the same as the steel tube without a concrete core.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권5호
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• pp.2267-2285
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• 2016

Information Centric Networking that uses content name instead of IP address as routing identifier can handle challenges such as traffic explosion and user mobility, but it also suffers from scalability and incompatibility problems. In this paper by combining the concept of software defined networking and Internet end to end arguments, we propose a wide area deployable software defined information centric networking service model named SD-ICN. SD-ICN employs a dual space structure that separates edge service network and core transmission network. The enhanced SDN techniques are used in edge service network in order to implement intelligent data routing and caching, while traditional IP technique is reserved in core transmission network so as to provide wide area high speed data transmission. Besides, a distributed name resolution system based on the cooperation of different controllers is also presented. The prototype experiments in our campus network show that SD-ICN can be deployed in a scalable and incremental way with no modification of the core network, and can support typical communication modes such as multicast, mobility, multihoming, load balancing, and multipath data transmission effectively.

• 대한간호학회지
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• 제47권5호
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• pp.600-612
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• 2017

Purpose: This study aimed to identify and compare hospice care research topics between Korean and international nursing studies using text network analysis. Methods: The study was conducted in four steps: 1) collecting abstracts of relevant journal articles, 2) extracting and cleaning keywords (semantic morphemes) from the abstracts, 3) developing co-occurrence matrices and text-networks of keywords, and 4) analyzing network-related measures including degree centrality, closeness centrality, betweenness centrality, and clustering using the NetMiner program. Abstracts from 347 Korean and 1,926 international studies for the period of 1998-2016 were analyzed. Results: Between Korean and international studies, six of the most important core keywords-"hospice," "patient," "death," "RNs," "care," and "family"-were common, whereas "cancer" from Korean studies and "palliative care" from international studies ranked more highly. Keywords such as "attitude," "spirituality," "life," "effect," and "meaning" for Korean studies and "communication," "treatment," "USA," and "doctor" for international studies uniquely emerged as core keywords in recent studies (2011~2016). Five subtopic groups each were identified from Korean and international studies. Two common subtopics were "hospice palliative care and volunteers" and "cancer patients." Conclusion: For a better quality of hospice care in Korea, it is recommended that nursing researchers focus on study topics of patients with non-cancer disease, children and family, communication, and pain and symptom management.

• Steel and Composite Structures
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• 제46권4호
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• pp.451-469
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• 2023

The use of precast hollow-core slabs (PCHCS) in civil construction has been increasing due to the speed of execution and reduction in the weight of flooring systems. However, in the literature there are no studies that present a finite element model (FEM) to predict the load-slip relationship behavior of pushout tests, considering headed stud shear connector and PCHCS placed at the upper flange of the downstand steel profile. Thus, the present paper aims to develop a FEM, which is based on tests to fill this gap. For this task, geometrical non-linear analyses are carried out in the ABAQUS software. The FEM is calibrated by sensitivity analyses, considering different types of analysis, the friction coefficient at the steel-concrete interface, as well as the constitutive model of the headed stud shear connector. Subsequently, a parametric study is performed to assess the influence of the number of connector lines, type of filling and height of the PCHCS. The results are compared with analytical models that predict the headed stud resistance. In total, 158 finite element models are processed. It was concluded that the dynamic implicit analysis (quasi-static) showed better convergence of the equilibrium trajectory when compared to the static analysis, such as arc-length method. The friction coefficient value of 0.5 was indicated to predict the load-slip relationship behavior of all models investigated. The headed stud shear connector rupture was verified for the constitutive model capable of representing the fracture in the stress-strain relationship. Regarding the number of connector lines, there was an average increase of 108% in the resistance of the structure for models with two lines of connectors compared to the use of only one. The type of filling of the hollow core slab that presented the best results was the partial filling. Finally, the greater the height of the PCHCS, the greater the resistance of the headed stud.

• Earthquakes and Structures
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• 제15권1호
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• pp.81-95
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• 2018

Most buildings feature core walls (and shear walls) that are placed eccentrically within the building to fulfil architectural requirements. Contemporary earthquake design standards require three dimensional (3D) dynamic analysis to be undertaken to analyse the imposed seismic actions on this type of buildings. A static method of analysis is always appealing to design practitioners because results from the analysis can always be evaluated independently by manual calculation techniques for quality control purposes. However, the equivalent static analysis method (also known as the lateral load method) which involves application of an equivalent static load at a certain distance from the center of mass of the buildings can generate results that contradict with results from dynamic analysis. In this paper the Generalised Force Method of analysis has been introduced for multi-storey buildings. Algebraic expressions have been derived to provide estimates for the edge displacement ratio taking into account the effects of dynamic torsional actions. The Generalised Force Method which is based on static principles has been shown to be able to make accurate estimates of torsional actions in seismic conditions. The method is illustrated by examples of two multi-storey buildings. Importantly, the black box syndrome of a 3D dynamic analysis of the building can be circumvented.

• Structural Engineering and Mechanics
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• 제57권2호
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• pp.239-263
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• 2016

The paper studies the natural oscillation of the three-layered solid sphere with a middle layer made of Functionally Graded Material (FGM). It is assumed that the materials of the core and outer layer of the sphere are homogeneous and isotropic elastic. The three-dimensional exact equations and relations of linear elastodynamics are employed for the investigations. The discrete-analytical method proposed by the first author in his earlier works is applied for solution of the corresponding eigenvalue problem. It is assumed that the modulus of elasticity, Poisson's ratio and density of the middle-layer material vary continuously through the inward radial direction according to power law distribution. Numerical results on the natural frequencies related to the torsional and spheroidal oscillation modes are presented and discussed. In particular, it is established that the increase of the modulus of elasticity (mass density) in the inward radial direction causes an increase (a decrease) in the values of the natural frequencies.

• International Journal of Advanced Culture Technology
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• 제12권1호
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• pp.51-59
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• 2024

Qiang ethnic group is one of the fifty-six ethnic minorities in China, and Qiang embroidery, as an important achievement of Qiang's intangible cultural heritage, is the precipitation and testimony of the history and culture of the Qiang ethnic group. However, with the development of the times, traditional and ancient Qiang embroidery is facing a dilemma due to the problem of a single form of communication. Therefore, it is necessary to add new communication media for Qiang embroidery to help it spread and develop better. In this paper, we extract the core representative patterns of Qiang embroidery, use the "shape grammars" as the rules of morphological changes, and generate new decorative pattern patterns with the characteristics of Qiang embroidery by adding, deleting, mirroring, rotating, and other relevant rules of changes, and combine the new patterns with the rules of formal beauty to combine the layout, which is then applied in the design of different cultural creations and products. The new patterns are combined with the rules of formal beauty and applied in the design of different cultural and creative products. To provide a quantitative method for the digital protection of Qiang embroidery in the new era of Chinese traditional art, and also provide new ideas for the industrialization application.

• 정보관리학회지
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• 제20권1호
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• pp.231-250
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• 2003

정보기술의 급격한 발전은 이용 가능한 정보량의 급증 뿐 만 아니라 정보의 형태에 있어서도 다양화를 가져왔다. 정보이용능력은 정보를 검색하고, 분석하고 이용하는데 필요한 기술이다. 이는 대학교육의 핵심 목표이자 도서관 교육의 새로운 경향으로 인식되고 있다. 그러나 급증하는 정보이용능력에 관한 관심에도 불구하고, 교육 프로그램이나 교수-사서간의 협력에 관한 논의는 부족한 실정이다. 도서관 교육이 교과과정의 일부가 되기 위해서는 대학구성원간의 긴밀한 협력이 반드시 필요하다. 본 연구는 외국 대학도서관에서 채택하고 있는 정보이용능력 교육 프로그램을 개관하고, 대학구성원간 협력에 있어 성공사례를 분석해보았다. 또한 이를 바탕으로 우리나라 대학에서 정보이용능력 교육의 시행에 필요한 절차의 개요를 제시해보았다

• Advances in nano research
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• 제8권4호
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• pp.323-333
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• 2020

In recent years, there has been an upsurge for the usage of buckling restrained braces (BRB) rather than ordinary braces, as they have evidently performed better. If the overall brace buckling is ignored, BRBs are proven to have higher energy absorption capacity and flexibility. This article aims to deliberate an economically efficient yet adequate type of all-steel BRB, comprised of the main components as in traditional ones, such as : (1) a steel core that holds all axial forces and (2) a steel restrainer tube that hinders buckling to occurr in the core; there is a more practical detailing in the BRB system due to the elimination of a filling mortar. An investigation has been conducted for the proposed rectangular-tube core BRB and it is hysteric behavioral results have been compared to previous researches conducted on a structure containing a similar plate core profile that has the same cross-sectional area in its core. A loss of strength is known to occur in the BRB when the limiting condition of local buckling is not satisfied, thus causing instability. This typically occurs when the thickness of the restrainer tube's wall is smaller than the cross-sectional area of the core plate or its width. In this study, a parametric investigation for BRBs with different formations has been performed to verify the effect of the design parameters such as different core section profiles, restraining member width to thickness ratio and relative cross-sectional area of the core to restrainer, on buckling load evaluation. The proposed BRB investigation results have also been presented and compared to past BRB researches with a plate profile as the core section, and the advantages and disadvantages of this configuration have been discussed, and it is concluded that BRBs with tubular core section exhibit a better seismic performance than the ones with a plate core profile.