• Smart Structures and Systems
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• v.26 no.5
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• pp.559-573
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• 2020

One of the powerful data management tools is Building Information Modeling (BIM) which operates through obtaining, recalling, sharing, sorting and sorting data and supplying a digital environment of them. Employing SHM, a BIM in monitoring systems, would be an efficient method to address their data management problems and consequently optimize the economic aspects of buildings. The recording of SHM data is an effective way for engineers, facility managers and owners which make the BIM dynamic through the provision of updated information regarding the occurring state and health of different sections of the building. On the other hand, digital transformation is a continuous challenge in construction. In a cloud-based BIM platform, environmental and localization data are integrated which shape the Internet-of-Things (IoT) method. In order to improve work productivity, living comfort, and entertainment, the IoT has been growingly utilized in several products (such as wearables, smart homes). However, investigations confronting the integration of these two technologies (BIM and IoT) remain inadequate and solely focus upon the automatic transmission of sensor information to BIM models. Therefore, in this composition, the use of BIM based on SHM and IOT is reviewed and the economic application is considered.

• Journal of Information Display
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• v.10 no.4
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• pp.149-157
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• 2009

Reported herein is the architecture for a nonvolatile n-type memory paper field-effect transistor. The device was built via the hybrid integration of natural cellulose fibers (pine and eucalyptus fibers embedded in resin with ionic additives), which act simultaneously as substrate and gate dielectric, using passive and active semiconductors, respectively, as well as amorphous indium zinc and gallium indium zinc oxides for the gate electrode and channel layer, respectively. This was complemented by the use of continuous patterned metal layers as source/drain electrodes.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.4
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• pp.429-435
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• 2012

An abrasion due to continuous friction between a work roll and strip causes the mass of the work roll to be unbalanced in the rolling process. We developed a mathematical model for the rolling mill considering the unbalanced mass and verified the model experimentally. The work roll was approximated as a rigid rotor with eccentricity, and the effect of the unbalanced mass on chatter vibration was investigated. The joint forces computed by quasistatic analysis were applied to the work roll in the rolling mill. Transient responses were obtained, and frequency analysis was performed by solving equations of motion using a direct integration method. Horizontal vibrations were more strongly affected by eccentricity than vertical vibrations. In the horizontal direction, a small eccentricity of 1% of the work roll radius considerably increased the amplitude of the chatter frequency.

• Transactions of Materials Processing
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• v.17 no.8
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• pp.633-642
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• 2008

It's important to measure quantitative properties about thermal-nano behavior of polymer for producing high quality components using Nanoimprint lithography process. Nanoscale indents can be used to make the cells for molecular electronics and drug delivery, slots for integration into nanodevices, and defects for tailoring the structure and properties. In this study, formability of polymethylmetacrylate(PMMA) and polycarbonate(PC) were characterized Polymer has extreme variation in thermo mechanical variation during forming high temperature. Because of heating the polymer, it becomes softer than at room temperature. In this case it is particularly important to study high temperature-induced mechanical properties of polymer. Nanoindenter XP(MTS) was used to measure thermo mechanical properties of PMMA and PC. Polymer was heated by using the heating stage on NanoXP. At CSM(Continuous Stiffness Method) mode test, heating temperature was $110^{\circ}C,120^{\circ}C,130^{\circ}C,140^{\circ}C$ and $150^{\circ}C$ for PMMA, $140^{\circ}C,150^{\circ}C,160^{\circ}C,170^{\circ}C$ and $180^{\circ}C$ for PC, respectively. Maximum indentation depth was 2000nm. At basic mode test, heating temperature was $90^{\circ}C$ and $110^{\circ}C$ for PMMA, $140^{\circ}C,160^{\circ}C$ for PC. Maximum load was 10mN, 20mN and 40mN. Also indented pattern was observed by using SEM and AFM. Mechanical properties of PMMA and PC decreased when temperature increased. Decrease of mechanical properties from PMMA went down rapidly than that of PC.

• Structural Engineering and Mechanics
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• v.59 no.3
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• pp.503-526
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• 2016

In-plane and out-of-plane free vibration analysis of Timoshenko curved beams is addressed based on the isogeometric method, and an effective scheme to avoid numerical locking in both of the two patterns is proposed in this paper. The isogeometric computational model takes into account the effects of shear deformation, rotary inertia and axis extensibility of curved beams, and is applicable for uniform circular beams, and more complicated variable curvature and cross-section beams as illustrated by numerical examples. Meanwhile, it is shown that, the $C^{p-1}$-continuous NURBS elements remarkably have higher accuracy than the finite elements with the same number of degrees of freedom. Nevertheless, for in-plane or out-of-plane vibration analysis of Timoshenko curved beams, the NURBS-based isogeometric method also exhibits locking effect to some extent. To eliminate numerical locking, the selective reduced one-point integration and $\bar{B}$ projection element based on stiffness ratio is devised to achieve locking free analysis for in-plane and out-of-plane models, respectively. The suggested integral schemes for moderately slender models obtain accurate results in both dominated and non-dominated regions of locking effect. Moreover, this strategy is effective for beam structures with different slenderness. Finally, the influence factors of structural parameters of curved beams on their natural frequency are scrutinized.

• Journal of Digital Convergence
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• v.14 no.8
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• pp.211-221
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• 2016

The rapid trends toward outsourcing and collaboration have created complex multi-tier supply chains for construction and engineering industries. Working with suppliers and sub-suppliers requires continuous integration activities in order to maximize the performances of the entire supply chain. The purpose of this study is to identify the factors influencing the performances and long-term business relationship of second-tier suppliers in directed sourcing environment. This study proposes the asset specificity, trust, information-sharing and collaboration, as antecedents variables, and collected the survey responses from the second-tier suppliers in rebar manufacturing works. The statistical results indicate that the asset specificity, trust, information-sharing and collaboration have significant influences on the long-term business relationship of rebar manufacturing second-tier suppliers, but trust has no impact on the performances of second-tier suppliers at 5% significance level. Practical implications are also discussed.

• The Research Journal of the Costume Culture
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• v.23 no.2
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• pp.294-309
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• 2015

This study aims to clarify the aesthetic values between emotion of human and expression of technology in contemporary fashion as it analyzes formative characteristics of related cases in fashion based on principles of 3D Printing technology and the viewpoint of mechanic aesthetics. The conclusions of this study are as follows. First, 3D Printing fashion is not only expressed diverse variations by its principles of formative methods, materials and properties, but also changes of silhouette by applying system of designers. Second, general characteristics of 3D Printing fashion is represented by various applications in SLS system, and it can be specifically explained application to a portion of clothing, decorative roles of clothing, complicated pattern making through crossing fabrics using 3D scanner and displaying a certain object changing fashion styles, and so forth. Third, the formative characteristics of 3D Printing fashion from the perspective of mechanic aesthetics is as follows. It can be analyzed as the integration of metaphysical values through compared symbolization of natural feature and technical evolution, partial dynamics and interactive velocity-based, formative combinations for abstract expression using architectural components, cosmos images and substantialized structures through images of organic space interacted human shapes. As the mention above, 3D Printing technology can creative a diverse area of fashion, and express images of new technological fashion through various works with continuous development of techniques.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.25 no.4
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• pp.235-263
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• 2014

Library of Congress introduced BIBFRAME as a new bibliographic framework to enhance web accessibility of bibliographic records and their integration to Web of data. This study introduces BIBFRAME model and its current status, reviews BIBFRAME classes and properties, and presents a mapping between MARC21 and BIBFRAME. The study aims to help the understanding the deployment of BIBFRAME in bibliographic description. BIBFRAME categorizes bibliographic entities into Work-Instance, and employs RDF/XML and URIs to identify resources and specify semantics of the resources on the Web. It also suggests an Annotation entity to provide additional information produced by users and external organizations. BIBFRAME is significant in that it presents a new paradigm of bibliographic description and expands users' information discovery in the context of Linked Data. Continuous researches are required to support its content model agnostic application to diverse resource type, which may entail a modification of BIBFRAME model and vocabulary. It also calls for guidelines for using the complicated vocabulary in a coherent way.

• Coupled systems mechanics
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• v.9 no.2
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• pp.163-182
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• 2020

Coupled thermo-mechanical analysis of reinforced concrete slab at elevated temperatures from a fire accounting for nonlinear thermal parameters is carried out. The main focus of the paper is put on a one-way continuous reinforced concrete slab exposed to fire from the single (bottom) side as the most typical working condition under fire loading. Although contemporary techniques alongside the fire protection measures are in constant development, in most cases it is not possible to avoid the material deterioration particularly nearby the exposed surface from a fire. Thereby the structural fire resistance of reinforced concrete slabs is mostly influenced by a relative distance between reinforcement and the exposed surface. A parametric study with variable concrete cover ranging from 15 mm to 35 mm is performed. As the first part of a one-way coupled thermo-mechanical analysis, transient nonlinear heat transfer analysis is performed by applying the net heat flux on the exposed surface. The solution of proposed heat analysis is obtained at certain time steps of interest by α-method using the explicit Euler time-integration scheme. Spatial discretization is done by the finite element method using a 1D 2-noded truss element with the temperature nodal values as unknowns. The obtained results in terms of temperature field inside the element are compared with available numerical and experimental results. A high level of agreement can be observed, implying the proposed model capable of describing the temperature field during a fire. Accompanying thermal analysis, mechanical analysis is performed in two ways. Firstly, using the guidelines given in Eurocode 2 - Part 1-2 resulting in the fire resistance rating for the aforementioned concrete cover values. The second way is a fully numerical coupled analysis carried out in general-purpose finite element software DIANA FEA. Both approaches indicate structural fire behavior similar to those observed in large-scale fire tests.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.4
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• pp.297-303
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• 2014

Using the bond-based peridynamics and the parallel computation with binary decomposition, an adjoint shape design sensitivity analysis(DSA) method is developed for the dynamic crack propagation problems. The peridynamics includes the successive branching of cracks and employs the explicit scheme of time integration. The adjoint variable method is generally not suitable for path-dependent problems but employed since the path of response analysis is readily available. The accuracy of analytical design sensitivity is verified by comparing it with the finite difference one. The finite difference method is susceptible to the amount of design perturbations and could result in inaccurate design sensitivity for highly nonlinear peridynamics problems with respect to the design. It turns out that $C^1$-continuous volume fraction is necessary for the accurate evaluation of shape design sensitivity in peridynamic discretization.