• Proceedings of the Computational Structural Engineering Institute Conference
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• 2011.04a
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• pp.324-327
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• 2011

The design requirement for ground mounted sign structures are fairly well defined in the AASHTO Standard Specifications for Structural Supports for Highway Signs, Luminaries, and Traffic Signals and consists of applying an equivalent pseudo-dynamic loading to account for the dynamic effects of wind loads and ignores the dynamic effect due to moving vehicle loads. This design approach, however, should not be applied to the design of bridge mounted sign structures because ignoring the dynamic effects of the moving vehicle loads may produce non-conservative results, since the stiffness of the bridge structure can greatly influence the behavior. Not enough information is available in the literatures which provide guide lines to include the influence of moving vehicles in the design of the bridge mounted sign structures. This paper describes a theoretical methodology, Bridge-Vehicle Interaction Element, which can be utilized to account for the dynamic effect of moving vehicles. A case study is also included where this methodology was successfully applied. It was concluded that the bridge-vehicle interaction finite element developed can provide a more accurate representation of the behavior of bridge mounted sign structures. The result of these analysis enabled development of simple and effective retrofitting scheme for the existing support system of bridge-mounted-structure.

• PNF and Movement
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• v.4 no.1
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• pp.27-36
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• 2006

Purpose : The main purpose of this study was to investigate the effect on Balance Ability of Knee Osteoarthritis(OA) by Lower Extremity Patterns with dynamic reverse in Proprioceptive Neuromuscular Facilitation(PNF). Methods : The subjects were consisted of 30 women patients with knee OA. All subjects were randomly assigned to PNF group. Each group had a treatment for 30 minutes per day and three times a week during 8 weeks period. Was used to measure recovery or worse of patient's condition, muscle assessment questionnaire(MAQ) was used to measure patient' s muscular strength, Endurance, coordination/balance, KWOMAC was used to pain, stiffness, and physical function, and BPM was used to measure path, anterior-posterior. Results : This study results in following conclusons. 1. MAQ score was significantly decreased in PNF group(p<.05). 2. KWOMAC score was significantly decreased in PNF group(p<.05). 3. BPM were score was significantly decreased in PNF group(p>.05). Conclusion : From this result the PNF treatment retrogression characteristic will be effective in treatment of patient, with the arthritis and widely may be applied at a therapist.

• Computational Structural Engineering : An International Journal
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• v.3 no.1
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• pp.1-7
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• 2003

For system identification of large structures, it is not practical to identify the entire structure due to the prohibitive computational time and difficulty in numerical convergence. This paper explores the possibility of performing system identification at substructure level, taking advantage of reduction in both the number of unknowns and the number of degrees of freedom involved. Another advantage is that different portions (substructures) of a structural system can be identified independently and even concurrently with parallel computing. Two substructural identification methods are formulated on the basis whether substructural approach is used to obtain first-order or second-order model. For substructural first-order model, identification at the substructure level will be performed by means of the Observer/Kalman filter Identification (OKID) and the Eigensystem Realization Algorithm (ERA) whereas identification at the global level will be performed to obtain second-order model in order to evaluate the system's stiffness and mass parameters. In the case of substructural second-order model, identification will be performed at the substructure level throughout the identification process. The efficiency of the proposed technique is shown by numerical examples for multi-storey shear buildings subjected to random forces, taking into consideration the effects of noisy measurement data. The results indicate that both the proposed methods are effective and efficient for damage identification of large structures.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2007.04a
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• pp.795-800
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• 2007

In the previous study, a simple but effective analysis procedure, named as an Improved Modal Pushover Analysis (IMPA) was proposed to estimates the seismic capacities of multi-span continuous bridge structures, on the basis of the modal pushover analysis which considers all the dynamic modes of a structure. Differently from other previous studies, IMPA maintains the simplicity of the capacity-demand curve method and also gives a better estimation of the maximum dynamic response of a structure. Nevertheless, its applicability has never been approved for multi-span continuous bridges with large differences in the length of their adjacent piers. This paper, accordingly, concentrates on a parametric study to verify the efficiency and limitation in application of IMPA through a correlation study between various analytical models including the Equivalent Single Degree Of Freedom (ESDOF) and Modal Pushover Analysis (MPA) usually used in the seismic design of structures. Based on the obtained numerical results, this paper introduces a practical guidance and/or limitation for using IMPA to predict the seismic response of a bridge effectively.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.20 no.4
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• pp.469-476
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• 2007

A domain/boundary decomposition technique is applied to carry out efficient finite element analyses of 3-D contact problems. Appropriate penalty functions are selected for connecting an interface and contact interfaces with neighboring subdomains that satisfy continuity constraints. As a consequence, all the effective stiffness matrices have positive definiteness, and computational efficiency can be improved to a considerable degree. If necessary, any complex-shaped 3-D domain can be divided into several simple-shaped subdomains without considering the conformity of meshes along the interface. With a set of numerical examples, the basic characteristics of computational efficiency are investigated carefully.

• Journal of the Society of Naval Architects of Korea
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• v.46 no.3
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• pp.290-302
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• 2009

Pipe system widely used in a ship is usually attached to the hull of a ship, and its vibration lead to structure-borne noise. Rubber mount is usually used as a vibration isolator of a pipe in a ship. In this paper, the effects of several factors, besides the stiffness and damping of the rubber mount, on vibration-isolating performance are taken into consideration. The parameters considered in this paper are hardness of the rubber material, painting on the rubber and deformation from clamping. Through the results of parametric study, the effective specifications of rubber mount are suggested to improve vibration-isolating performance. The performance under fluid flowing condition is calculated numerically and verified experimentally.

• Journal of International Academy of Physical Therapy Research
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• v.9 no.1
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• pp.1420-1425
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• 2018

The purpose of this study was to investigate the effect of traction and decompression therapies on the cervical muscle tone and disc height. The decompression group (n=16) received decompression therapy and Mckenzie exercises once a day and four times a week respectively, for three weeks. The traction group (n=15) also received traction therapy and Mckenzie exercises for the same period. Muscle tone was measured with a myotonometer, and the disk height was measured using magnetic resonance imaging (MRI), before the interventions. Three weeks later, we investigated the therapeutic effect by repeating these measurements. The difference in disk height between the two groups was not significant. There was a significant difference in the disk herniation index (p<.05). A significant difference was found only in the upper trapezius muscle after comparison of muscle tone and stiffness between the groups (p<.05). Findings from this study suggest that the decompression therapy is a more effective intervention for patients with cervical intervertebral disc herniation.

• Journal of Institute of Control, Robotics and Systems
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• v.11 no.5
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• pp.451-456
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• 2005

This paper describes three kinds of experiments and analysis of their results related to human tactile sensitivity using an integrated tactile display system. The device can provide vibration, normal pressure and lateral slip/stretch which are important physical quantities to sense texture. We have tried to find out the efficient method of stimulating, limitation of surface discrimination by kinesthetic farce feedback and the effectiveness of the combination of kinesthetic force and tactile feedback. Seven kinds of different stimulating methods were carried out and they are single or combination of the kinesthetic force, normal static pressure, vibration, active/passive shear and moving wave. Both prototype specimen and stimulus using tactile display were provided to all examinees and they were allowed to answer the most similar sample. The experimental results show that static pressure is proper stimulus for the display of micro shape of the surface and vibrating stimulus is more effective for the display of fine surface. And the sensitivities of active touch and passive touch are compared. Since kinesthetic force feedback is appropriate to display shape and stiffness of an object, but roughness display has a limitation of resolution, the concurrent providing methods of kinesthetic and tactile feedback are applied to simulate physical properties during touching an object.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.6
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• pp.909-915
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• 2010

In order to determine the most effective ratio of black soybean powder as an ingredient in cake, black soybean power was added at ratio of 10, 20, 30, and 40% versus wheat flour set as 0(control). Black soybean powder consisted of moisture(8.44%), crude protein(31.34%), crude fat(6.64%), crude ash(3.88%) and carbohydrates(49.70%). The specific gravity, spreadability, and baking loss increased according to the amount of black soybean powder, although specific volume decreased. The chromaticity 'L' and 'b' values of sponge cake with black soybean powder showed an reducing trend while the 'a' value displayed an increasing trend with an increase in black soybean powder. The texture properties of sponge cake with added black soybean powder showed an increasing trend in hardness and stiffness when the cake contained more black soybean powder. The sensory test for sponge cake with added black soybean powder showed high preference for 20% added black soybean powder to sponge cake.

• Journal of Computational Design and Engineering
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• v.2 no.2
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• pp.88-95
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• 2015

Recently, fiber composite materials have been attracting attention from industry because of their remarkable material characteristics, including light weight and high stiffness. However, the costs of products composed of fiber materials remain high because of the lack of effective manufacturing and designing technologies. To improve the relevant design technology, this paper proposes a novel simulation method for deforming fiber materials. Specifically, given a 3D model with constant thickness and known fiber orientation, the proposed method simulates the deformation of a model made of thick fiber-material. The method separates a 3D sheet model into two surfaces and then flattens these surfaces into two dimensional planes by a parameterization method with involves cross vector fields. The cross vector fields are generated by propagating the given fiber orientations specified at several important points on the 3D model. Integration of the cross vector fields gives parameterization with low-stretch and low-distortion.