• Earthquakes and Structures
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• v.22 no.2
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• pp.121-135
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• 2022

Many public buildings such as schools, hospitals, etc., where partial infill walls are present in reinforced concrete (RC) structures, have undergone undesirable damage/failure attributed to captive column effect during a moderate to severe earthquake shaking. Often, the situation gets worsened when these RC frames are non-ductile in nature, thus reducing the deformable capability of the frame. Also, in many parts of the Indian subcontinent, it is mandatory to use fly-ash bricks for construction so as to reduce the burden on the disposal of fly-ash produced at thermal power plants. In some scenario, when the non-ductile RC frame, partially infilled by fly-ash bricks, suffers major structural damage, the challenge remains on how to retrofit and restore it. Thus, in this study, two full-scale one-bay, one-story non-ductile RC frame models, namely, bare frame and RC partially infilled frame with fly-ash bricks in 50% of its opening area are considered. In the previous experiments, these models were subjected to slow-cyclic displacement-controlled loading to replicate damage due to a moderate earthquake. Now, in this study these damaged frames were retrofitted and an experimental investigation was performed on the retrofitted specimens to examine the effectiveness of the proposed retrofitting scheme. A hybrid retrofitting technique combining epoxy injection grouting with an innovative and easy-to-implement steel jacketing technique was proposed. This proposed retrofitting method has ensured proper confinement of damaged concrete. The retrofitted models were subjected to the same slow cyclic displacement-controlled loading which was used to damage the frames. The experimental study concluded that the hybrid retrofitting technique was quite effective in enhancing and regaining various seismic performance parameters such as, lateral strength and lateral stiffness of partially fly-ash brick infilled RC frame. Thus, the steel jacketing retrofitting scheme along with the epoxy injection grouting can be relied on for possible repair of the structural members which are damaged due to the captive column effect during the seismic shaking.

• Earthquakes and Structures
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• v.10 no.6
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• pp.1369-1389
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• 2016

The soil-structure interaction effect significantly influences the design of multi-storey buildings subjected to lateral seismic loads. The shear walls are often provided in such buildings to increase the lateral stability to resist seismic loads. In the present work, the nonlinear soil-structure analysis of a G+5 storey RC shear wall building frame having isolated column footings and founded on deformable soil is presented. The nonlinear seismic FE analysis is carried out using ANSYS software for the building with and without shear walls to investigate the effect of inclusion of shear wall on the moments in the footings due to differential settlement of soil mass. The frame is considered to behave in linear elastic manner, whereas, soil mass to behave in nonlinear manner. It is found that the interaction effect causes significant variation in the moments in the footings. The comparison of non-interaction and interaction analyses suggests that the presence of shear wall causes significant decrease in bending moments in most of the footings but the interaction effect causes restoration of the bending moments to a great extent. A comparison is made between linear and nonlinear analyses to draw some important conclusions.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.5
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• pp.422-427
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• 2012

This study investigates on the relationship between total load which is caused by infiltration and insulation thickness against compensation effect. As the result of experiment, the PVC(Synthetic resins sash) window frame in airtightness is superior to the AL(Aluminum sash) window frame. In this study, as the increasing of insulation thickness in reference building does not reduce significantly cooling load, the compensation effect due to airtightness against infiltration is very small. But the compensation effect against infiltration can be closely related with heating load. Therefore, the proper thermal insulation thickness can be needed respect to cooling and heating load.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.5
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• pp.113-117
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• 2011

The frame for automotive assembly can be deformed and remained on the residual stress due to high temperature thermal attacks when in welding. The frame deformation can be made to problems when in assembly with body and the residual stress can affect the negative effect on durability performance of the automobile. In order to analyze the frame deformation, the simplified test frame which had the similar shape (form) of the real automotive frame was fabricated. The contactless optical 3D scanner was used for the shape difference measurement of the frame between before and after the welding. The FE-model of the test frame was composed and the heat transfer and thermal stress simulation were performed. The simulated results were compared with the measured results for the reference of the frame design. The deformation shape of the frame by simulation was in good agreement with that by the experimental measurement.

• Communications of the Korean Mathematical Society
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• v.36 no.2
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• pp.257-266
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• 2021

In this paper, by using the sequence of adjointable operators from C^*-algebra 𝓐 into Hilbert 𝓐-module E, the woven frames of multipliers in Hilbert C^*-modules are introduced. Meanwhile, we study the effect of operators on these frames and, also we construct the new woven frame of multipliers in Hilbert 𝓐-module 𝓐. Finally, compositions of woven frames of multipliers in Hilbert C^*-modules are studied.

• Journal of Communications and Networks
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• v.2 no.1
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• pp.69-75
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• 2000

A new frame synchronization confirmation technique using a pilot pattern of both uplink and downlink channels is proposed for W-CDMA (Wideband Code Division Multiple Access) system. It is shown that by using this technique, we can cancel the side lobe for autocorrelation functions of the frame synchronization words of pilot pattern have the maximum to-of-phase autocorrelation value "4" with two peak values equal in magnitude and opposite in polarity at zero and middle shifts. Due to this side lobe cancellation effect, therefore, the autocorrelation function of the frame synchronization words becomes ideal for the frame synchronization confirmation since double maximum correlation values equal in magnitude and opposite polarity at zero ad middle shifts can be achieved. This property can be used to double check frame synchronization timing and thus. improve the frame synchronization confirmation performance.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.04a
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• pp.353-360
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• 2002

The objective of this study is to develop a technique that analyzes the global behavior of frame structures with local cracks. The technique is based on frame analysis and uses the stiffness matrix of cracked frame element. An algorithm proposed here analyzes a frame structure with local transverseedge cracks, considering the effects of crack length and location. Stress intensity factors are employed to calculate additional local compliance due to the cracks based on linear elastic fracture mechanics theory, and then this local compliance is utilized to derive the stiffness matrix of the cracked frame element. In order to verify the accuracy and reliability of the proposed approach, numerical results are compared with those of Finite Element Method for the cracked frame element, and the effects of single crack on the behavior of truss structure are also examined.

• Transactions of Materials Processing
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• v.17 no.6
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• pp.436-442
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• 2008

As the structure of a mobile phone becomes thin to catch up with a slim product trend, the structural strength and resistance to shock of TFT-LCD module are getting to be reduced. Hence, TFT-LCD module is the strength reinforced by bezel frame. The bezel frame was produced by the multi hemming processes with several folding parts. The determination of the optimal number of hemming part and structure of bezel frame are very important process parameter to obtain the strength of that. The effect of process parameters on strength of bezel frame was investigated by FEA. Based on the result of FEA, the experiment was performed using manufactured hemming die, the result of the experiment was compared with FEA and verified. Also, three point bending tests were performed to check the strength of bezel frame.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.1
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• pp.72-77
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• 2014

There are two main technologies to implement cloud effect in flight simulator, cloud modeling using particle system and texture mapping. In former case, this approach may cause a low frame rate while unrealistic cloud effect is observed in latter case. To Solve this problem, in this paper, we propose how to apply fog effect into camera to display more realistic cloud effect with high frame rate. The proposed method is tested with massive terrain database environment through implemented software by using OpenSceneGraph. As a result, compared to texture mapping method, the degree of difference on frame rate is 1 or 2Hz while the cloud effect is significantly improved as realistic as particle system.

• Earthquakes and Structures
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• v.8 no.5
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• pp.1255-1276
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• 2015

The importance of considering soil-structure interaction effect in the analysis and design of RC frame buildings is increasingly recognized but still not penetrated to the grass root level owing to various complexities involved. It is well established fact that the soil-structure interaction effect considerably influence the design of multi-storey buildings subjected to lateral seismic loads. The shear walls are often provided in such buildings to increase the lateral stability to resist seismic lateral loads. In the present work, the linear soil-structure analysis of a G+5 storey RC shear wall building frame resting on isolated column footings and supported by deformable soil is presented. The finite element modelling and analysis is carried out using ANSYS software under normal loads as well as under seismic loads. Various load combinations are considered as per IS-1893 (Part-1):2002. The interaction analysis is carried out with and without shear wall to investigate the effect of inclusion of shear wall on the total and differential settlements in the footings due to deformations in the soil mass. The frame and soil mass both are considered to behave in linear elastic manner. It is observed that the soil-structure interaction effect causes significant total and differential settlements in the footings. Maximum total settlement in footings occurs under vertical loads and inner footings settle more than outer footings creating a saucer shaped settlement profile of the footings. Each combination of seismic loads causes maximum differential settlement in one or more footings. Presence of shear wall decreases pulling/pushing effect of seismic forces on footings resulting in more stability to the structures.