Structural Reliability Techniques Research Articles

Smart Digital Marketing Capabilities for Sustainable Property Development: A Case of Malaysia

Digital tools and marketing have been widely adopted in various industries throughout the world. These tools have enabled companies to obtain real-time customer insights and create and communicate value to customers more effectively. This study aims at understanding the principles and practices of sustainable digital marketing in the Malaysian property development industry by investigating the extent to which digital marketing has been adopted, the impediments to its adoption, and the strategies to improve digital capabilities for the local context. Digital marketing theories, practices, and models from other industries are adopted and applied to the local property development industry to lay the foundation for making it smart and sustainable. This paper proposes a marketing technology acceptance model (MTAM) for digital marketing strategy and capability development. The key factors used in the model are ease of use, perceived usefulness, perceived cost, higher return, efficiency, digital service quality, digital information quality, digital system quality, attitude towards use, and actual use. The model and hypothetical relationships of critical factors are tested using structural modeling, reliability, and validity techniques using a sample of 279 Malaysian property development sector representatives. A quantitative approach is adopted, using an online questionnaire tool to investigate the behavior of respondents on the current digital marketing practices and capabilities of Malaysian property development companies. The results show that the sample property development companies are driven by the benefit of easily obtaining real-time customer information for creating and communicating value to customers more effectively through the company brand. Further strategies, such as creating real-time interactions, creating key performance indicators to measure digital marketing, personalization, and encouraging innovation in digital marketing are most preferred by local professionals. An adoption framework is provided based on the reviewed models and results of the current study to help transform the Malaysian property development sector into a smart and sustainable property development sector by facilitating the adoption of digital technologies. The results, based on real-time data and pertinent strategies for improvement of the local property sector, are expected to pave the way for inducing sustainable digital marketing trends, enhancing capabilities, and uplifting the state of the property development sector in developing countries.

Integrated Risk-Informed Design (I-RID) methodological framework and computational application for FLEX equipment storage buildings of Nuclear Power Plants

In this research, an Integrated Risk-Informed Design (I-RID) methodological framework is developed for generating and evaluating design options for Nuclear Power Plant (NPP) structures and for providing plant decision makers with a quantitative comparison among design options based on multiple decision criteria, e.g., safety risk and cost. In the I-RID framework, simulations of underlying failure mechanisms are integrated with Probabilistic Risk Assessment (PRA) (consisting of event trees and fault trees) and a cost assessment model in a unified framework. The failure mechanisms are simulated by conducting Finite Element Analysis (FEA), and a probabilistic interface between FEA and the existing plant PRA is generated using structural reliability techniques. A causal model for cost assessment is developed, which allows for the modeling of multi-layer causal relationships among underlying contributing factors and, therefore, creates an explicit connection between cost and safety risk outputs. This paper applies the I-RID framework to the design of a storage building for the Diverse and Flexible Coping Strategies (FLEX) equipment in an NPP subjected to a potential tornado impact. Over two hundred design options are generated and evaluated, and three suggested design options with the lowest values of safety risk and cost are identified.

Probabilistic assessment of connections for steel buildings on seismic zones

The findings about the fragile behavior of steel welded connections after the Northridge 1994 earthquake, specially for frames designed to withstand lateral force, have brought an amount of new attention to the design and safety issues of the welded connections for structures located on seismic zones. In México, practitioners and designers are wondering about the seismic effectiveness of the several kinds of connections as used in steel structures.A decision must be made to balance the safety required with the costs incurred after exceeding the serviceability limit state. Structural reliability techniques provide the proper framework to include the inherent uncertainties into the design process.Registered motions after the 1985 Mexico City earthquake are properly scaled according to the seismic hazard curve for soft soil in Mexico City. Earthquake occurrence is modeled as a Poisson process and the expected life-cycle cost is taken as the decision criteria.Parametric analyses allow the identification of dominant variables and ranges where one option is more recommendable than the other one.The proposed formulation may support designers and builders for the decision making process about the selection of the convenient connection type for the seismic zones with soft soil in Mexico City.

Selección de conexiones de acero para zonas sísmicas basada en información de riesgo

The fi ndings about the fragile behavior of steel welded connections after the Northridge 1994 earthquake, specially for frames designed to withstand lateral force, has brought an amount of new a�4 ention to the design and safety issues of the welded connections for structures located on seismic zones. In Mexico, practitioners and designers are wondering about the seismic e�� ectiveness of the several kinds of connections as used in steel structures. A decision must be made to balance the safety required with the costs incurred after exceeding the serviceability limit state. Structural reliability techniques provide the proper framework to include the inherent uncertainties into the design process. Registered motions after the 1985 Mexico City earthquake are properly scaled according to the seismic hazard curve for soft soil in Mexico City. Earthquake occurrence is modeled as a Poisson process and the expected life-cycle cost is taken as the decision criteria. Parametric analyses allow the identifi cation of dominant variables and ranges where one option is more recommendable than the other one. The proposed formulation may support designers and builders for the decision making process about the selection of the convenient connection type for the seismic zones with soft soil in Mexico City.

Security risks and probabilistic risk assessment of glazing subject to explosive blast loading

A probabilistic risk assessment (PRA) procedure is developed which can predict risks of explosive blast damage to built infrastructure. The present paper focuses on window glazing since this is a load-capacity system which, when subject to blast loading, has caused significant damage and injury to building occupants. Structural reliability techniques are used to derive fragility and blast reliability curves (BRCs) for annealed and toughened glazing subjected to explosive blast, for a variety of threat scenarios. The probabilistic analyses include the uncertainties associated with blast modelling, glazing response and glazing failure criteria. Damage risks are calculated for an individual window and for windows in the facade of a multi-storey commercial building. If threat probabilities can be estimated then the paper shows illustrative examples of how this information, when combined with risk-based decision-making criteria, can be used to optimise risk mitigation strategies.

Design-point excitation for non-linear random vibrations

It has been shown in recent years that certain non-linear random vibration problems can be solved by well established methods of time-invariant structural reliability, such as FORM and importance sampling. A key step in this approach is finding the design-point excitation, which is that realization of the input process that is most likely to give rise to the event of interest. It is shown in this paper that for a non-linear, elastic single-degree-of-freedom oscillator subjected to white noise, the design-point excitation is identical to the excitation that generates the mirror image of the free-vibration response when the oscillator is released from a target threshold. This allows determining the design-point excitation with a single non-linear dynamic analysis. With a slight modification, this idea is extended to non-white and non-stationary excitations and to hysteretic oscillators. In these cases, an approximate solution of the design-point excitation is obtained, which, if necessary, can be used as a ‘warm’ starting point to find the exact design point using an iterative optimization algorithm. The paper also offers a simple method for computing the mean out-crossing rate of a response process. Several examples are provided to demonstrate the application and accuracy of the proposed methods. The methods proposed in this paper enhance the feasibility of approximately solving non-linear random vibration problems by use of time-invariant structural reliability techniques.

Calibration of Casing/Tubing Design Criteria by Use of Structural Reliability Techniques

SummaryThis paper reviews the state-of-the-art in casing/tubing structural reliability analysis, and the knowledge gained from it to date. Results are presented to show that, as previously suspected, burst design based on casing full of gas is over-conservative for non-critical wells. However, the risk-calibrated design criteria are strongly dependent on the design philosophy for underground blowout loads. It is demonstrated that well control is the largest single factor in reducing risk; gaps in current knowledge are identified, and recommendations made for future work.

Overview of advanced structural and reliability techniques for optimum design of fixed offshore platforms

The paper addresses the increasing use of advanced structural and reliability techniques in design optimisation of fixed offshore platforms. Recent changes in regulatory and contract practices within the offshore industry coupled with developments in structural and reliability methods and increased hardware capacity create a suitable framework for increased design optimisation. The paper examines the current impact of advanced structural analysis techniques at component and system level and examines how recent developments in structural system reliability techniques are likely to affect the design process in future. Areas that need to be addressed before we are able to maximise the benefits from the use of these techniques are discussed together with recommendations for a more effective integration in the design process.

Structural reliability techniques applied to plume impingement loading of the Space Station Freedom photovoltaic array

A new aerospace application of structural reliability techniques is presented, where the applied forces depend on many probabilistic variables. This application is the plume impingement loading of the Space Station Freedom Photovoltaic Arrays. When the space shuttle berths with Space Station Freedom it must brake and maneuver towards the berthing point using its primary jets. The jet exhaust, or plume, may cause high loads on the photovoltaic arrays. The many parameters governing this problem are highly uncertain and random. An approach, using techniques from structural reliability, as opposed to the accepted deterministic methods, is presented which assesses the probability of failure of the array mast due to plume impingement loading. A Monte Carlo simulation of the berthing approach is used to determine the probability distribution of the loading. A probability distribution is also determined for the strength of the array. Structural reliability techniques are then used to assess the array mast design. These techniques are found to be superior to the standard deterministic dynamic transient analysis, for this class of problem. The results show that the probability of failure of the current array mast design due to the examined failure modes is minute. Significantly, this paper details a structural reliability analysis of a complex aerospace structure for which little statistical information is available.

Second moment reliability analysis of redundant systems with dependent failures

Second moment modelling provides an excellent tool for analysing the reliability of complex systems subject to performance-related failures. This paper presents a general, efficient approach to second moment modelling, and shows how this method can be combined with established structural reliability techniques to provide reliability estimates for series systems. Dependencies resulting from correlated component properties and correlated loads are handled automatically by this method. The second moment analysis is then extended to cover the case of redundant systems subject to cascade failures, in which the system topology changes through the failure sequence. The formulation considers both the dependence of system performance on topology and the dependence among topologies to provide estimates of failure rates based on the preceding failure sequence. The overall procedure is demonstrated for a simple example. The method is presented in a general matrix form applicable to a wide variety of probabilistic physical systems, and suitable for direct implementation in software.