• 콘크리트학회논문집
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• 제17권6호
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• pp.1065-1074
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• 2005

Due to lack of information, current design methods to calculate bearing strength of connections are tacit about cases in which hybrid coupled walls have connection details of stud bolts and horizontal ties. In this study, analytical study was carried out to develop model for calculating the connections strength of embedded steel section. The bearing stress at failure in the concrete below the embedded steel coupling beam section is related to the concrete compressive strength and the ratio of the width of the embedded steel coupling beam section to the thickness of the shear walls. Experiments were carried out to determine the factors influencing the bearing strength of the connection between steel coupling beam and reinforced concrete shear wall. The test variables included the reinforcement details that confer a ductile behavior in connection between steel coupling beam and shear wall, i. e., the auxiliary stud bolts attached to the steel beam flanges and the transverse ties at the top and the bottom steel beam flanges. In addition, additional test were conducted to verify the strength equations of the connection between steel coupling beam and reinforced concrete shear wall. The results of the proposed equations in this study are in good agreement with both our test results and other test data from the literature.

• Structural Engineering and Mechanics
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• 제8권6호
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• pp.607-622
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• 1999

Being a significant mode of deformation, shear effect in addition to the other modes of stretching and bending have been considered to develop two finite element models for the analysis of beams on elastic foundation. The first beam model is developed utilizing the differential-equation approach; in which the complex variables obtained from the solution of the differential equations are used as interpolation functions for the displacement field in this beam element. A single element is sufficient to exactly represent a continuous part of a beam on Winkler foundation for cases involving end-loadings, thus providing a benchmark solution to validate the other model developed. The second beam model is developed utilizing the hybrid-mixed formulation, i.e., Hellinger-Reissner variational principle; in which both displacement and stress fields for the beam as well as the foundation are approxmated separately in order to eliminate the well-known phenomenon of shear locking, as well as the newly-identified problem of "foundation-locking" that can arise in cases involving foundations with extreme rigidities. This latter model is versatile and indented for utilization in general applications; i.e., for thin-thick beams, general loadings, and a wide variation of the underlying foundation rigidity with respect to beam stiffness. A set of numerical examples are given to demonstrate and assess the performance of the developed beam models in practical applications involving shear deformation effect.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2007년도 춘계학술대회 논문집
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• pp.326-330
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• 2007

Bumper back beam is one of the essential structural components of front-end module. It should be designed to withstand a minor bump in low-speed collision, 2.5 mph crash test for example. And weight reduction is always important problem in the design of almost all the parts in car for energy saving. So, the key issues in shape design of a bumper are weight reduction and the performance in 2.5mph crash test. In this study, a light weight and high performance bumper back beam model was developed using analytical approach based on mechanics and FE simulation together.

• International journal of advanced smart convergence
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• 제9권2호
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• pp.58-67
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• 2020

In this paper, we propose a data-driven-based beam selection scheme for massive multiple-input and multiple-output (MIMO) systems in ultra-dense networks (UDN), which is capable of addressing the problem of high computational cost of conventional coordinated beamforming approaches. We consider highly dense small-cell scenarios with more small cells than mobile stations, in the millimetre-wave band. The analog beam selection for hybrid beamforming is a key issue in realizing millimetre-wave UDN MIMO systems. To reduce the computation complexity for the analog beam selection, in this paper, two deep neural network models are used. The channel samples, channel gains, and radio frequency beamforming vectors between the access points and mobile stations are collected at the central/cloud unit that is connected to all the small-cell access points, and are used to train the networks. The proposed machine-learning-based scheme provides an approach for the effective implementation of massive MIMO system in UDN environment.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.113-116
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• 2004

No specific guidelines are for computing the shear strength of steel coupling beam connections embedded in the reinforced concrete shear wall. In this paper, a theoretical study of the strength of hybrid coupled shear wall connections is achieved. The bearing stress at failure in the concrete below the steel coupling beam section is related to the concrete compressive strength and the ratio of the width of the steel coupling beam section to the thickness of the hybrid coupled shear wall. To revise factor affecting shear transfer strength across connections between coupled shear walls and steel coupling beam, experimental studies are achieved. The main test variables were auxiliary details of stud bolts. In this studies, these proposed equations are shown to be in good agreement with the test results reported in the paper and with other test data in the literature.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 가을 학술발표논문집(II)
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• pp.597-602
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• 1998

The composite systems, consisting of R/C Columns-Steel Beams, are reasonable structures because of their constructional and economical advantages, workability and so on. But, it is difficult to apply the composite systems to actual design due to material dissimilarity and complicate stress flow in the connection. This study aims to propose the hybrid beam-column connection system with structural tee and through experimental research make clear the shear and moment resistance capacity and stress transfer mechanism.

• International Journal of Precision Engineering and Manufacturing
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• 제4권1호
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• pp.37-42
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• 2003

Active control of flexural vibrations of smart laminated composite beams has been carried out using piezoceramic sensor/actuator and viscoelastic material. The beams with passive constrained layer damping have been analyzed by formulating the equations of motion through the use of extended Hamilton's principle. The dynamic characteristics such as damping ratio and modal damping of the beam are calculated for various fiber orientations by means of iterative complex eigensolution method. This paper addresses a design strategy of laminated composite under flexural vibrations to design structure with maximum possible damping capacity.

• 한국공간구조학회논문집
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• 제16권3호
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• pp.99-106
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• 2016

The proposed hybrid damper installs at a coupling beam and consists of a high-damping rubber (HDR) and steel pin. The proposed hybrid damper adopted a pin-lock system acts as a viscoelastic damper under wind load (small displacement) while it behaves as a hysteretic damper under earthquake load (large displacement). In this paper, the pin-lock mechanism and structural performance of the proposed hybrid damper is evaluated through experiment. Experiments were carried out with the variables which displacement, loading frequency and steel pin quantities were used. Test results showed that the pin-lock mechanism and the performance of the hybrid damper under a large displacement were verified. Also equivalent damping ratios of HDR were increasing at a small displacement as displacement amplitudes were increasing. However HDR did not depend on frequency.

• 한국진공학회:학술대회논문집
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• 한국진공학회 1994년도 제6회 학술발표회 논문개요집
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• pp.129-129
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• 1994

• Journal of Welding and Joining
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• 제30권4호
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• pp.44-48
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• 2012

H-beam used for stiffening the upper structure of ocean plant is cut in the various shapes. The cutting process of the H-beam is done manually and requires a long time and high cost. Therefore, automation of H-beam cutting is an important task. This research aims to develop a 3-D simulator to build the automatic H-beam cutting system and to determine the optimal cutting method. The automatic H-beam cutting system composes of 6 robots including 2 cutting robots hang to a crane and 1 conveyer. The appropriate system layout for covering the various sizes and types of H-beam was tested and determined using the simulator. The H-beam cutting system uses a hybrid type of plasma and gas cutting because of special cutting shapes of H-beam. The cutting area of each cutting method should be properly divided according to the size and shape of H-beam to shorten the total cutting time. Additionally the collision between a robot and a robot or a robot and H-beam should be avoided. The optimal cutting method for the shortest cutting time without the collision could be found for the various cutting conditions by use of the simulator. 2 simulation samples shows the availability of the simulator to find the optimal cutting method.