• Structural Engineering and Mechanics
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• v.6 no.3
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• pp.291-304
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• 1998

This paper deals with the non-axisymmetric dynamic response of an imperfectly bonded buried orthotropic pipeline subjected to longitudinal wave (P-wave) excitation. An infinite cylindrical shell model, including the rotary inertia and shear deformation effects, has been used for the pipeline. For some cases comparison of axisymmetric and non-axisymmetric responses have also been furnished.

• Structural Engineering and Mechanics
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• v.20 no.1
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• pp.45-67
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• 2005

This paper presents a new approach to predict the racking load-displacement response of plasterboard clad walls found in Australian light-framed residential structures under monotonic racking load. The method is based on a closed-form mathematical model, described herein as the 'Modularised' Closed-Form Mathematical model or MCFM model. The model considers the non-linear behaviour of the connections between the plasterboard cladding and frame. Furthermore, the model is flexible as it enables incorporation of different nailing patterns for the cladding. Another feature of this model is that the shape of stud deformation is not assumed to be a specific function, but it is computed based on the strain energy approach to take account of the actual load deformation characteristics of particular walls. Verification of the model against the results obtained from a detailed Finite Element (FE) model is also reported. Very good agreement between the closed form solution and that of the FE model was achieved.

• Structural Engineering and Mechanics
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• v.6 no.7
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• pp.773-784
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• 1998

To assess the collapse risk of transmission line structures subject to natural hazards, it is important to identify what hazard may cause the structural collapse. In Australia and many other countries, a large proportion of failures of transmission line structures are caused by severe thunderstorms. Because the wind loads generated by thunderstorms are not only random but time-variant as well, a time-dependent structural reliability approach for the risk assessment of transmission line structures is essential. However, a lack of appropriate stochastic models for thunderstorm winds usually makes this kind of analysis impossible. The intention of the paper is to propose a stochastic model that could realistically and accurately simulate wind loading due to severe thunderstorms. With the proposed thunderstorm model, the collapse risk of transmission line structures under severe thunderstorms is assessed numerically based on the computed failure probability of the structure.

• Structural Engineering and Mechanics
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• v.46 no.1
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• pp.111-135
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• 2013

An experimental study has been carried out on square plain concrete (PC) and reinforced concrete (RC) columns strengthened with carbon fiber-reinforced polymer (CFRP) sheets. A total of 78 specimens were loaded to failure in axial compression and investigated in both axial and transverse directions. Slenderness of the columns, number of wrap layers and concrete strength were the test parameters. Compressive stress, axial and hoop strains were recorded to evaluate the stress-strain relationship, ultimate strength and ductility of the specimens. Results clearly demonstrate that composite wrapping can enhance the structural performance of square columns in terms of both maximum strength and ductility. On the basis of the effective lateral confining pressure of composite jacket and the effective FRP strain coefficient, new peak stress equations were proposed to predict the axial strength and corresponding strain of FRP-confined square concrete columns. This model incorporates the effect of the effective circumferential FRP failure strain and the effect of the effective lateral confining pressure. The results show that the predictions of the model agree well with the test data.

• 한국디지털정책학회:학술대회논문집
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• 2003.12a
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• pp.479-488
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• 2003

With rapid changes in the business environment, many organizations pursue to manage cost management and performance management of the organizational business activities over the concept of profit management strategically, But the strategic enterprise management system is implemented individually and is not integrated. And the integrated model of strategic enterprise management is ambiguous and many consulting firms didn't suggested the proper model yet. Therefore in this study we studied the strategic enterprise management system, And we studied how to try to integrate the various components of the strategic enterprise management system through the case of the domestic L company site that implemented ABC/ABM, ABS, BSC, business planning & forecasting system recently.

• Journal of Industrial Convergence
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• v.7 no.1
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• pp.83-100
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• 2009

The purpose of this study was to investigate the influence of Perceived Organizational Support(POS) and on Organizational Citizenship Behavior through Organizational Commitment(OC). In order to attain the objectives of this study, a model was established and hypothesis was verified on the basis of preceding studies. In a model proposed for this study, POS was used as antecedents to OC while OCB was used as consequences for OC. The sample included 387 employees. Structural equation modeling(SEM) was used to employed the hypothesized relationships in the conceptual model. Results indicated that (a)POS has a positive impact OC; (b)affective OC has a positive impact OCB; (c)continuance OC has a negative(or zero) impact QCB. Implications are discussed and future research directions are outlined.

• Membrane and Water Treatment
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• v.7 no.4
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• pp.327-339
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• 2016

Nanofiltration is useful to concentrate propolis extract. During the selection of membrane, both compound rejection and permeate flux are important indicators of process economy. Brazilian green propolis extract was studied to evaluate the separation performance of Startmen 122 and NF270 membranes. Compared to Starmen 122, NF270 membrane showed better rejection of bioactive compounds. The flux decline patterns were further studied using Hermia's model. Cake formation is the major fouling mechanism on the hydrophobic surface of Starmen 122. While the fouling mechanism for NF270 is pore blocking. The fouled membranes were further characterized using SEM and FT-IR to confirm on the predicted fouling mechanisms.

• Journal of Korea Foundry Society
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• v.13 no.3
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• pp.276-284
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• 1993

The interfacial phenomena between intermetallic compounds and Al matrix have been studied at $680^{\circ}C$ for various holding time under argon atmosphere. Model experiments were performed using Fe, Ni and Ti wire to observe the interfacial phenomena. The interfacial phenomena between intermetallic compounds and Al matrix were analysed by optical microscope, SEM and EDX. The results of EDX and XRD showed that the interfacial zones of intermetallic compounds/Al matrix were composed of several intermetallic layers. The reaction layer was varied with holding time and heating temperature. The investigation of interfacial zones in the specimen as a function of heat treatment time at $680^{\circ}C$ indicated that the best heat treatment condition for squeeze casting was $680^{\circ}C$ for 5min.

• Structural Engineering and Mechanics
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• v.61 no.5
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• pp.577-592
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• 2017

A computing procedure is presented to predict the ultimate behavior of prestressed beams under torsion. This computing procedure is based on an extension of the Variable Angle Truss-Model (VATM) to cover both longitudinal and transversal prestressed beams. Several constitutive relationships are tested to model the behavior of the concrete in compression in the struts and the behavior of the reinforcement in tension (both ordinary and prestress). The theoretical predictions of the maximum torque and corresponding twist are compared with some results from reported tests and with the predictions obtained from some codes of practice. One of the tested combinations of the relationships for the materials was found to give simultaneously the best predictions for the resistance torque and the corresponding twist of prestressed beams under torsion. When compared with the predictions from some codes of practice, the theoretical model which incorporates the referred combination of the relationships provides best values for the torsional strength and leads to more optimized designs.

• Structural Engineering and Mechanics
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• v.12 no.6
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• pp.685-698
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• 2001

In this paper, a general method for the automatic search for Strut-and-Tie (S&T) models representative of possible resistant mechanisms in reinforced concrete elements is proposed. The representativeness criterion here adopted is inspired to the principle of minimum strain energy and requires the consistency of the model with a reference stress field. In particular, a highly indeterminate pin-jointed framework of a given layout is generated within the assigned geometry of the concrete element and an optimum truss is found by the minimisation of a suitable objective function. Such a function allows us to search the optimum truss according to a reference stress field deduced through a F.E.A. and assumed as representative of the given continuum. The theoretical principles and the mathematical formulation of the method are firstly explained; the search for a S&T model suitable for the design of a deep beam shows the method capability in handling the reference stress path. Finally, since the analysis may consider the structure as linear-elastic or cracked and non-linear in both the component materials, it is shown how the proposed procedure allows us to verify the possibilities of activation of the design model, oriented to the serviceability condition and deduced in the linear elastic field, by following the evolution of the resistant mechanisms in the cracked non-linear field up to the structural failure.