• Steel and Composite Structures
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• v.26 no.1
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• pp.89-102
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• 2018

This work investigates a novel plate formulation and a modified couple stress theory that introduces a variable length scale parameter is presented to discuss the static and dynamic of functionally graded (FG) micro-plates. A new type of third-order shear deformation theory of Reddy that use only 4 unknowns by including undetermined integral variables is proposed in this study. The equations of motion are derived from Hamilton's principle. Analytical solutions are obtained for a simply supported micro-plate. Numerical examples are presented to examine the effect of the length scale parameter on the responses of micro-plates. The obtained results are compared with the previously published results to demonstrate the correctness of the present formulation.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.514-518
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• 1996

This paper focuses on automated generation of the knowledge base for a fuzzy network performance manager in order to satisfy delay constraints imposed on time-critical messages while maintaining as much network capacity as possible for non-time-critical messages. Therefore, the bowlegs base is formulated to minimize a certain penalty function by using a type of genetic algorithm. The efficacy of the formulation method has been demonstrated by a series of simulation experiments.

• Computers and Concrete
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• v.1 no.2
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• pp.131-150
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• 2004

We present in this work a coupled phenomenological chemo-mechanical model that represents the degradation of concrete-like materials. The chemical behaviour is described by the nowadays well known simplified calcium leaching approach. And the mechanical damage behaviour is described by a continuum damage model which involves the gradient of the damage quantity. The coupled nonlinear problem at hand is addressed within the context of the finite element method. For the equation governing the calcium dissolution-diffusion part of the problem, special care is taken to treat the highly nonlinear calcium conductivity and solid calcium functions. The algorithmic design is based on a Newton-type iterative scheme where use is made of a recently proposed relaxed linearization procedure. And for the equation governing the damage part of the problem, an augmented Lagrangian formulation is used to take into account the damage irreversibility constraint. Finally, numerical simulations are compared with experimental results on cement paste.

• Structural Engineering and Mechanics
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• v.55 no.4
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• pp.815-837
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• 2015

A new family of structure-dependent integration methods is developed to enhance with desired numerical damping. This family method preserves the most important advantage of the structure-dependent integration method, which can integrate unconditional stability and explicit formulation together, and thus it is very computationally efficient. In addition, its numerical damping can be continuously controlled with a parameter. Consequently, it is best suited to solving an inertia-type problem, where the unimportant high frequency responses can be suppressed or even eliminated by the favorable numerical damping while the low frequency modes can be very accurately integrated.

• Proceedings of the KSR Conference
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• 2002.10a
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• pp.690-695
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• 2002

Two plate girders bridge has an advantage for execution of works and quality control because of its simplicity of super-structure caused by decreasing in amount of members and also is distinguished as aesthetic bridge type. Recently this has been adopted for structure of highway as well railway and introduced into domestic. In order to plan or design two plate girders bridge more rationably, it is necessary to comprehend its structural behavior as well as to consider the critical resign factors. Thus, in this study the formulation of optimum design for two plate girders bridge is proposed and the critical resign variables ani restraints are considered and founded by caring out optimum design. The objective function of optimization is formulated as a minimum cost design problem. And the thickness and length of I-shaped section are decided as resign variables. The design constraints are formulated based on Design Criteria for Railroad(Bridges). By comparing the optimum results with those of the conventional resign, the effectiveness of proposed optimum design formulation is investigated. From the results, the way to do optimum design of two plate girders bridge is suggested.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.8
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• pp.1022-1030
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• 1999

This paper is concerned with the balancing motion formulation and the control of ZMP (zero moment point) for a biped walking robot with balancing joints. The balancing equation of a biped robot can be modeled as the second order non-homogeneous differential equation, which makes it possible to plan the desired trajectories for various gaits or motions. Also, the balancing motion can be defined easily by solving the differential equation without pre-processing or heuristic procedures. The actual experiments are performed on biped walking robot system IWR-III, developed in our Automatic Control Lab. The system has the structure of three pitches in each leg, and one roll and one prismatic type in balancing joints. The walking simulations and the experimental results on IWR-III are shown using the proposed formula and control algorithm.

• Advances in concrete construction
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• v.8 no.3
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• pp.199-206
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• 2019

High performance sandcretes (HPS) are new concretes characterized by particles having a diameter less than 5 mm, as well as very high mechanical strength and durability. This work consists in finding solutions to make sandcretes with good physico-mechanical and durability properties for this new generation of micro-concrete. However, upgrading ordinary sandcrete into high performance sandcrete (HPS) requires a thorough study of formulation parameters (equivalent water/binder ratio, type of cement and its dosage, kind and amount of super plasticizer, and gravel/sand ratio). This research study concerns the formulation, characterization and durability, in a sulphate environment, of a high performance sandcrete (HPS), made from local materials. The obtained results show that the rheological properties of fresh concrete and mechanical strength differ with the mineralogy, density and grain size distribution of sands and silica fume used.

• The Journal of Korean Medicine
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• v.35 no.3
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• pp.60-69
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• 2014

Background: Herbal formulas are generally served as a type of decoction. However, there is no scientific evidence for determining preservation and circulation period of herbal medicine decoctions. Thus, we investigated anti-inflammatory and anti-oxidative effects of the Gwakhyangjeonggi-san decoction according to its preservation period. Methods: Gwakhyangjeonggi-san decoction was stored for 0, 1, 2 or 3 months at room temperature. To evaluate anti-inflammatory effects, enzyme-linked immunosorbent assays (ELISAs) for tumor necrosis factor-alpha (TNF-${\alpha}$) and interleukin-6 (IL-6), and nitric oxide (NO) assay were conducted using the culture supernatant from RAW 264.7 cells stimulated with lipopolysaccharide (LPS). The antioxidant activities were studied by measuring free radical scavenging activities on ABTS and DPPH. Results: Gwakhyangjeonggi-san decoction maintained the inhibitory effects on TNF-${\alpha}$, IL-6 and NO productions after up to 2 months of storage in LPS-treated RAW 264.7 cells. No inflammatory response was observed in 3 months of storage. In addition, the scavenging activities on ABTS and DPPH of Gwakhyangjeonggi-san decoction were reduced time-dependently and showed less than 50% inhibition after 3 months of storage. Conclusions: Our results suggest that preservation period of Gwakhyangjeonggi-san decoction is recommended within 2 months after storage.

• Journal of Digital Convergence
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• v.13 no.8
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• pp.369-374
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• 2015

In this study, by combining a unique purpose and additional aspects of ultrasonic transmission media, a development potential on a new ultrasonic transmission media was sought. The rheological characteristics and the manufacturing cost for each manufactured formulation were compared and analysed with ready-made. An ultrasonic transmission media is to have different functional characteristics according to the following formulation, it was the best in rheological value, low viscosity emulsion with the oil gel. Polymer hydro gel is can be manufactured at low cost compared to other formulations. Emulsion which shows a sharp viscosity difference according to the components of oil and water had a big difference in manufacturing cost. This study can be utilized as the fundamental data on the ultrasound transmission media equipped with expertise in various areas of ultrasound.

• Fashion & Textile Research Journal
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• v.3 no.5
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• pp.455-465
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• 2001

Assessing soil removal is of interest to the washing machine industry because of government-mandated energy savings and changes in detergent formulation and consumer laundry practices. We designed this study to examine the laundry process from a holistic perspective by integrating factors perceived to be of importance. Our purpose was to assess the impact of selected variables (fabric and soil type, wash temperature and time. detergent amount, and degree of agitation) on soil removal using accelerated laundry conditions. We used the Taguchi method to develop the research design and ANOVA to analyze the data. Although soil removal was affected by fabric type, soil type, type and amount of detergent, degree of agitation, wash time and temperature, and water hardness and volume, wash temperature was the most significant variable.