• Journal of the Computational Structural Engineering Institute of Korea
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• v.17 no.4
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• pp.433-442
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• 2004

The aim of this paper is to study the interaction between adjacent buildings with different foundation levels under earthquake loading conditions. Buildings and soil are represented by two different models. In the first case, the building itself is modeled with standard frame element, whereas the soil behavior is stimulated by a special grid model. In the second case, the building and soil are represented by plane stress or plane strain elements. The modulus of elasticity of the 9round as well as the varying relations of inertia have a strong influence on the section forces within the buildings. The Interaction between the two buildings is demonstrated and discussed via numerical examples using the proposed method.

• Fire Science and Engineering
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• v.17 no.4
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• pp.42-56
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• 2003

This research made a survey to 119 EMT laying stress on general contents connected with job in a frame of mutually organic cooperation system between the processes, composing Emergency Medical Care Transportation Policy in Korea, as a step before hospital, of happening emergency patients, 119 first-aid service of the spot, transportation of patients, construction of communication network etc.. As a result of analysis to that, it is found that there must be systematic devices which makes EMT not to be caught on medical dispute, a modernization of emergency equipments, professional first-aid agents, a proper personnel arrangement. Consequently, it suggests policy plan focusing on structural and functional aspect to improve an Emergency Medical Care Transportation system into a realistic one.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2002.06a
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• pp.1-6
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• 2002

This study has been advanced to the design method for embodying the hydraulic circuit and control device in considering the safety for the development of wheelchair lift, using in the public transportation bus. Recently, mobility and accessibility occurs for the elder and the handicapped in the aging problem, In this paper, we design the hydraulic power system to operate lifter loading one wheelchair handicapped person and one's supporter to get in the bus. We develop the lifter safely. We check the trajectories of lifter inside frame box to protect its corrosion and the stress at the joints of mechanical structure. Those can be helped to keep the safety and accuracy of the multiple dynamic systems for precision quality assurance in mass production.

• Journal of Microbiology and Biotechnology
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• v.5 no.3
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• pp.125-131
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• 1995

A 3, 346 bp of the cdd upstream region in Bacillus subtilis was sequenced from the pSO1 (Song BH and J Neuhard. 1989. Mol. Gen. Genet 216: 462-468) and sequence homology was searched to the known genes in Genbank and European Molecular Biology Laboratory databanks. Five complete and one truncated putative coding sequences deduced from the nucleotide sequence were found through the ORF searching by Genetyx and Macvector software, and one of them was identified as the dgk (diacylglycerol kinase) gene and another, a truncated one, as the phoH (phosphate starvation-inducible gene) gene. The B. subtilis dgk gene, having a role for response to several environmental stress signals, revealed an open reading frame of 134 amino acids with 43.1% of sequence identity to the Streptococcus mutans dgk gene. The carboxy terminal 59 residues of the truncated phoH gene showed 52.7% and 34.5% of sequence identity in amino acids with the corresponding genes of Mycobacterium leprae and Escherichia coli. The four remaining coding sequences consisting of 115, 421, 91, and 91 residues were thought to be unknown ORFs because they have no significant similarity to known genes.

• Structural Engineering and Mechanics
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• v.42 no.6
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• pp.815-829
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• 2012

This paper proposes a nonlinear computational modeling approach for the behaviors of structural systems subjected to fire. The proposed modeling approach consists of fire dynamics analysis, nonlinear transient-heat transfer analysis for predicting thermal distributions, and thermomechanical analysis for structural behaviors. For concretes, transient heat formulations are written considering temperature dependent heat conduction and specific heat capacity and included within the thermomechanical analyses. Also, temperature dependent stress-strain behaviors including compression hardening and tension softening effects are implemented within the analyses. The proposed modeling technique for transient heat and thermomechanical analyses is first validated with experimental data of reinforced concrete (RC) beams subjected to high temperatures, and then applied to a bridge model. The bridge model is generated to simulate the fire incident occurred by a gas truck on April 29, 2007 in Oakland California, USA. From the simulation, not only temperature distributions and deformations of the bridge can be found, but critical locations and time frame where collapse occurs can be predicted. The analytical results from the simulation are qualitatively compared with the real incident and show good agreements.

• Structural Engineering and Mechanics
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• v.25 no.4
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• pp.365-382
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• 2007

A pilot study has been conducted to guide the development of a finite element modeling formulation for the analysis of architectural glass curtain walls under in-plane lateral load simulating earthquake effects. This pilot study is one aspect of ongoing efforts to develop a general prediction model for glass cracking and glass fallout for architectural glass storefront and curtain wall systems during seismic loading. For this study, the ANSYS finite element analysis program was used to develop a model and obtain the stress distribution within an architectural glass panel after presumed seismic movements cause glass-to-frame contact. The analysis was limited to static loading of a dry-glazed glass curtain wall panel. A mock-up of the glass curtain wall considered in the analysis with strain gages mounted at select locations on the glass and the aluminum framing was subjected to static loading. A comparison is made between the finite element analysis predicted strain and the experimentally measured strain at each strain gage location.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.9 no.5
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• pp.76-82
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• 2010

In this study, we carried out to evaluate the shock-proof of a large scale motor for the naval vessel using dynamic design analysis method (DDAM) and full transient dynamic analysis. Analytical models for main assemblies (motor frame, rotor and stator assembly) were consisted of the tetrahedral solid elements and the equipments which installed in the upper side of the motor were substituted the mass elements. And we also modelled resilient mounts of a motor using the beam elements with appropriate directional stiffness. The DDAM was conducted according to NRL memorandum report 1396 and the full transient dynamic analysis was performed applying directional triple half triangle shock wave to the motor using ANSYS 12. As a result, we could compare of the results according to each analytic method and find the motor to satisfy the design criteria of the maximum stress and deformation.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.04a
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• pp.185-191
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• 2002

In this study a 3-dimensional analytical model is developed, which can analyses dynamic responses of curved bridges subject to moving vehicles. A 5-axle semi-trailer is modeled to simulate the actual tire forces that are redistributed by vehicle rolling effect due to the centrifugal force. The 1-span curved bridge with two steel box girders is modeled using the frame elements. The dynamic response characteristics of curved box girder bridges are examined and compared for two different support conditions. One is the case that two shoes are arranged at the outer sides of box girders with larger space between the two shoes and the other is that two shoes at the center of each box girder. In the curved bridges, the dynamic effect of moving vehicles influences the reaction force much more than other responses, such as displacement or stress, especially the upward reaction of inner-radius shoes. It is more advantageous for the reaction considering dynamic effect when shoes are arranged further at the outer sides of box girders than when shoes at the center of each box. The shoes for curved bridges with two-box girder system should be arranged to have larger distance.

• Structural Engineering and Mechanics
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• v.23 no.5
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• pp.579-597
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• 2006

The behaviour of reinforced concrete moment resisting frame structures in recent earthquakes all over the world has highlighted the consequences of poor performance of beam column joints. Large amount of research carried out to understand the complex mechanisms and safe behaviour of beam column joints has gone into code recommendations. This paper presents critical review of recommendations of well established codes regarding design and detailing aspects of beam column joints. The codes of practice considered are ACI 318M-02, NZS 3101: Part 1:1995 and the Eurocode 8 of EN 1998-1:2003. All three codes aim to satisfy the bond and shear requirements within the joint. It is observed that ACI 318M-02 requires smaller column depth as compared to the other two codes based on the anchorage conditions. NZS 3101:1995 and EN 1998-1:2003 consider the shear stress level to obtain the required stirrup reinforcement whereas ACI 318M-02 provides stirrup reinforcement to retain the axial load capacity of column by confinement. Significant factors influencing the design of beam-column joints are identified and the effect of their variations on design parameters is compared. The variation in the requirements of shear reinforcement is substantial among the three codes.

• Earthquakes and Structures
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• v.9 no.5
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• pp.957-981
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• 2015

Earthquakes occur as a cluster in many regions around the world where complex fault systems exist. The repeated shaking usually induces accumulative damage to affected structures. Damage accumulation in structural systems increases their level of degradation in stiffness and also reduces their strength. Many existing analytical tools of modeling RC structures lack the salient damage features that account for stiffness and strength degradation resulting from repeated earthquake loading. Therefore, these tools are inadequate to study the response of structures in regions prone to multiple earthquakes hazard. The objective of this paper is twofold: (a) develop a tool that contains appropriate damage features for the numerical analysis of RC structures subjected to more than one earthquake; and (b) conduct a parametric study that investigates the effects of multiple earthquakes on the response of RC moment resisting frame systems. For this purpose, macroscopic constitutive models of concrete and steel materials that contain the aforementioned damage features and are capable of accurately capturing materials degrading behavior, are selected and implemented into fiber-based finite element software. Furthermore, finite element models that utilize the implemented concrete and steel stress-strain hysteresis are developed. The models are then subjected to selected sets of earthquake sequences. The results presented in this study clearly indicate that the response of degrading structural systems is appreciably influenced by strong-motion sequences in a manner that cannot be predicted from simple analysis. It also confirms that the effects of multiple earthquakes on earthquake safety can be very considerable.