• Korean Journal of Construction Engineering and Management
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• v.15 no.3
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• pp.113-119
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• 2014

Recently, the demand on the practical application of life-cycle cost effectiveness for design and rehabilitation of structure is rapidly growing unprecedently in engineering practice. Accordingly, in the 21st century, it is almost obvious that life-cycle cost together with value engineering will become a new paradigm for all engineering decision problems in practice. However, in spite of impressive progress in the researches on the LCC, the most researches have only focused on the Deterministic or Probabilistic LCC analysis approach (Level-1 LCC Model) at design stage. Thus, the goal of this study is to develop a practical and realistic methodology for the Lifetime risk based Life-Cycle Cost (LCC)-effective optimum decision-making at design stage.

• Geomechanics and Engineering
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• v.37 no.6
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• pp.565-576
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• 2024

In this study, the earthquake risk assessment of single-story RC precast buildings in Turkey was carried out using loss curves. In this regard, Kocaeli, a seismically active city in the Marmara region, and this building class, which is preferred intensively, were considered. Quality and period parameters were defined based on structural and geometric properties. Depending on these parameters, nine main sub-classes were defined to represent the building stock in the region. First, considering the mean fragility curves and four different central damage ratio models, vulnerability curves for each sub-class were computed as a function of spectral acceleration. Then, probabilistic seismic hazard analyses were performed for stiff and soft soil conditions for different earthquake probabilities of exceedance in 50 years. In the last step, 90 loss curves were derived based on vulnerability and hazard results. Within the scope of the study, the comparative parametric evaluations for three different earthquake intensity levels showed that the structural damage ratio values for nine sub-classes changed significantly. In addition, the quality parameter was found to be more effective on a structure's damage state than the period parameter. It is evident that since loss curves allow direct loss ratio calculation for any hazard level without needing seismic hazard and damage analysis, they are considered essential tools in rapid earthquake risk estimation and mitigation initiatives.

• Smart Structures and Systems
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• v.9 no.1
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• pp.1-20
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• 2012

In bridge engineering, maintenance strategies and thus budgetary demands are highly influenced by construction type and quality of design. Nowadays bridge owners and planners tend to include life-cycle cost analyses in their decision processes regarding the overall design trying to optimize structural reliability and durability within financial constraints. Smart permanent and short term monitoring can reduce the associated risk of new design concepts by observing the performance of structural components during prescribed time periods. The objectives of this paper are the discussion and analysis of influence line or influence field approaches in terms of (a) an efficient incorporation of monitoring information in the structural performance assessment, (b) an efficient characterization of performance indicators for the assessment of structures, (c) the ability of optimizing the positions of sensors of a monitoring system, and (d) the ability of checking the robustness of the monitoring systems applied to a structure. The proposed influence line- model correction approach has been applied to an integrative monitoring system that has been installed for the performance assessment of an existing three-span jointless bridge.

• Coupled systems mechanics
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• v.9 no.5
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• pp.433-454
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• 2020

In-place analysis for offshore platforms is essentially required to make proper design for new structures and true assessment for existing structures. The structural integrity of platform components under the maximum and minimum operating loads of environmental conditions is required for risk assessment and inspection plan development. In-place analyses have been executed to check that the structural member with all appurtenances robustness and capability to support the applied loads in either storm condition or operating condition. A nonlinear finite element analysis is adopted for the platform structure above the seabed and the pile-soil interaction to estimate the in-place behavior of a typical fixed offshore platform. The analysis includes interpretation of dynamic design parameters based on the available site-specific data, together with foundation design recommendations for in-place loading conditions. The SACS software is utilized to calculate the natural frequencies of the model and to obtain the response of platform joints according to in-place analysis then the stresses at selected members, as well as their nodal displacements. The directions of environmental loads and water depth variations have important effects on the results of the in-place analysis behavior. The result shows that the in-place analysis is quite crucial for safe design and operation of offshore platform and assessment for existing offshore structures.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.9
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• pp.3973-3980
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• 2014

Prostate adenocarcinoma is one of the leading causes of cancer related mortality in men but still limited knowledge is available about its associated functional SNPs including rs1042522 (Pro72Arg). The present study was undertaken to explore the association of this SNP with susceptibility to prostate adenocarcinoma along with its structural and functional impacts in the Pakistani population in a case-control study. Three-dimensional structure of human TP53 with Pro72Arg polymorphism was predicted through homology modeling, refined and validated for detailed structure-based assessment. We also carried out a HuGE review of the previous available data for this polymorphism. Different genetic models were used to evaluate the genotypes association with the increased risk of PCa (Allelic contrast: OR=0.0.34, 95%CI 0.24-0.50, p=0.000; GG vs CC: OR=0.17, 95%CI 0.08-0.38, p=0.000; Homozygous: OR=0.08, 95%CI 0.04-0.15, p=0.000; GC vs CC: OR=2.14, 95%CI 1.01-4.51, p=0.046; Recessive model: OR=0.10, 95%CI 0.05-0.18, p=0.000; Log Additive: OR=3.54, 95%CI 2.13-5.89, p=0.000) except the Dominant model (OR=0.77, 95%CI 0.39-1.52, p=0.46). Structure and functional analysis revealed that the SNP in the proline rich domain is responsible for interaction with HRMT1L2 and WWOX. In conclusion, it was observed that the Arg coding G allele is highly associated with increased risk of prostate adenocarcinoma in the Pakistani population (p=0.000).

• Management Science and Financial Engineering
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• v.12 no.1
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• pp.65-77
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• 2006

This study proposes a Bayesian dynamic model in a hierarchical way to assess the time-varying effect of risk factors on the likelihood of corporate bankruptcy. For the longitudinal data, we aim to describe dynamically evolving effects of covariates more articulately compared to the Generalized Estimating Equation approach. In the analysis, it is shown that the proposed model outperforms in terms of sensitivity and specificity. Besides, the usefulness of this study can be found from the flexibility in describing the dependence structure among time specific parameters and suitability for assessing the time effect of risk factors.

• Journal of Aerospace System Engineering
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• v.10 no.2
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• pp.7-13
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• 2016

Multi disciplinary approach for aerodynamics, structure, propulsion, and flight control system is necessary to develop High Altitude Long Endurance Unmanned Aerial Vehicles (HALE UAV). Various HALE UAV development trends are surveyed to understand their operational requirements. Separating the UAV Take Off Weight by 150kg, Airworthiness implementation direction for HALE UAV is studied under the current Airworthiness regulations. NATO STANAG 4671 and STANAG 4703 Airworthiness certification criteria are analyzed, and their applicability was proposed for future HALE UAV development. In addition, minimization of the risk for UAV is studied by considering probability of cumulative catastrophic failure for HALE UAV. This Hazard Risk Index can support the future UAV Airworthiness Certification Criteria.

• The KIPS Transactions:PartC
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• v.12C no.7 s.103
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• pp.989-998
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• 2005

Information systems are today becoming larger and mostly broadband-networked. This exposes them at a higher risk of intrusions and hacking than ever before. Of the technologies developed to meet information system security needs, risk analysis is currently one of the most actively researched areas. Meanwhile, due to the extreme diversity of assets and complexity of network structure, there is a limit to the level of accuracy which can be achieved by an analysis tool in the assessment of risk run by an information system. Also, the results of a risk assessment are most oftennot up-to-date due to the changing nature of security threats. By the time an evaluation and associated set of solutions are ready, the nature and level of vulnerabilities and threats have evolved and increased, making them obsolete. Accordingly, what is needed is a risk analysis tool capable of assessing threats and propagation of damage, at the same time as security solutions are being identified. To do that, the information system must be simplified, and intrusion data must be diagrammed using a modeling technique this paper, we propose a modeling technique information systems to enable security risk analysis, using SPICE and Petri-net, and conduct simulations of risk analysis on a number of case studies.

• Environmental Analysis Health and Toxicology
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• v.30 no.sup
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• pp.7.1-7.10
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• 2015

Objectives For successful adoption of legislation controlling registration and assessment of chemical substances, it is important to obtain sufficient toxicological experimental evidence and other related information. It is also essential to obtain a sufficient number of predicted risk and toxicity results. Particularly, methods used in predicting toxicities of chemical substances during acquisition of required data, ultimately become an economic method for future dealings with new substances. Although the need for such methods is gradually increasing, the-required information about reliability and applicability range has not been systematically provided. Methods There are various representative environmental and human toxicity models based on quantitative structure-activity relationships (QSAR). Here, we secured the 10 representative QSAR-based prediction models and its information that can make predictions about substances that are expected to be regulated. We used models that predict and confirm usability of the information expected to be collected and submitted according to the legislation. After collecting and evaluating each predictive model and relevant data, we prepared methods quantifying the scientific validity and reliability, which are essential conditions for using predictive models. Results We calculated predicted values for the models. Furthermore, we deduced and compared adequacies of the models using the Alternative non-testing method assessed for Registration, Evaluation, Authorization, and Restriction of Chemicals Substances scoring system, and deduced the applicability domains for each model. Additionally, we calculated and compared inclusion rates of substances expected to be regulated, to confirm the applicability. Conclusions We evaluated and compared the data, adequacy, and applicability of our selected QSAR-based toxicity prediction models, and included them in a database. Based on this data, we aimed to construct a system that can be used with predicted toxicity results. Furthermore, by presenting the suitability of individual predicted results, we aimed to provide a foundation that could be used in actual assessments and regulations.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.25 no.5
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• pp.381-388
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• 2012

In this study, a seismic risk analysis performed for an applicability assessment of steel fiber in containment structures. Steel fiber can increase tensile properties of concrete structures moreover compressive and shear capacity. But many of researches about steel fiber reinforced concrete structures are now only focused in axial load condition. Also it is very difficult to find an effort for application to containment structures in NPP. Therefore, in this study, seismic fragility assessment for a steel fiber reinforced concrete containment structure. As a result, a seismic fragility capacity improved according to increase of shear and ductile capacity of concrete. In the case of 1.0% of steel fiber volume fraction, seismic capacity increases as 10%. But very limited previous experimental results were used in this study, so various element tests were needed for more accurate investigation.