Abstract We present two improvements on the technique of importance sampling. First, we show that sampling from a mixture densities, using those densities as control variates, results in useful upper bound asymptotic variance. That is small multiple variance best single component density. This allows one to benefit great reductions obtainable by sampling, while protecting against equally increases might take practitioner surprise. The second improvement how or more can be used approach zero...

Structural deformation is an important consideration in the health monitoring of bridges, and its dependence on temperature variations quite complex. Based field measurements performed for operational cable-stayed bridge, proposed study investigates mechanisms thermally induced girder length mid-span deflection through plane geometric finite element analyses. The objective this to understand behaviour such bridges over annual diurnal cycles. It has been observed that a bridge exhibit...

With the aging of existing steel bridges and accumulated stress cycles under traffic loads, assessment remaining fatigue life for continuing service has become more important than ever, especially decisions on structure replacement, deck or other major retrofits. Experience from engineering practice indicates that analysis based specification loads distribution factors usually underestimates by overestimating live load ranges. Fatigue evaluation field-measured range histograms actual proves...

This study proposes analytical formulas of the temperature-induced displacements that can be applied to general suspension bridges with any number spans. The take account tower lateral stiffness and elastic deformation cables caused by tension changes, which have not been studied in previous studies. derived are validated field monitoring data four-span Maanshan Yangtze River Bridge. A succinct unified one-dimensional formula is further for practical use. enables engineers better understand...

Excessive exploitation of the groundwater has resulted in obvious three-dimensional (3D) deformation features on surface Beijing Plain. This paper, by combining Interferometric Synthetic Aperture Radar (InSAR) and Global Positioning System (GPS) technologies, obtained time-series information 3D Plain, analyzing its spatial distribution characteristics. On this basis, relationship between different controlling factors with been analyzed as well. The following results are obtained: (1) From...

Both full-order and reduced-order energy-to-peak filtering problem for discrete-time singular systems are investigated. The purpose is to design a filter with desired order, such that the resulting error regular, casual stable while closed-loop transfer function from noises output satisfies prescribed l2−l∞ norm bound constraint. First, based on some augment technique, generalised bounded real lemma guaranteed performance derived. Then, necessary sufficient conditions solvability of obtained...

This study investigates the relationship between temperature and modal frequencies of bridges through a series model experiments using concrete continuous beam bridge steel cable-stayed in controlled-temperature chamber. The experimental results show that, for given boundary condition absence freezing, change affects structural as it alters elastic modulus materials. frequency tends to linearly decrease with increasing smaller than that bridges. For particular case wet bridges, dependencies...

Variation of temperature is a primary environmental factor that affects the behavior structures. Therefore, understanding mechanisms normal temperature-induced variations structural would help in distinguishing them from anomalies. In this study, we used health monitoring data Shanghai Yangtze River Bridge, steel girder cable-stayed bridge, to investigate thermally induced vertical deflection (<TEX>$D_T$</TEX>) at mid-span such bridges. The <TEX>$D_T$</TEX> results multisource combination...

Handwritten mathematical expression recognition (HMER) is a multidisciplinary task that generates LaTeX sequences from images. Existing approaches, employing tree decoders within attention-based encoder-decoder architectures, aim to capture the hierarchical structure, but are limited by CFGs and pre-generated triplet data, hindering expandability neglecting visual ambiguity challenges. This article investigates distinctive language characteristics of expressions, revealing two key...

With the magnitude of some stress cycles in a live load range spectrum being higher than constant amplitude fatigue limit (CAFL) structural detail, development crack could be expected. The current procedure AASHTO specifications for life estimation utilizes an equivalent with direct extension S-N lines slope −3 to below CAFL. This approach is conservative; however, it often results overprediction damage and underestimation safe useful details. A set bilinear curves knee at CAFL strength...

Bridges are fundamental facilities in the transportation system, and their operational performance is crucial for economic social development. Many large bridges now equipped with structural health monitoring (SHM) systems that collect various types of real-time data. However, our user study found despite accumulation massive amounts data, current analysis methods cannot efficiently process large-scale, high-dimensional To address this, we have developed BOPVis, a visualization system bridge...

This paper discusses a comprehensive investigation and retrofit for extensive fatigue cracks in the end connections of floor beams on double-deck, cantilever-suspended steel truss bridge. The involved three-dimensional (3D) finite-element analyses using global local models, field measurement strains displacements due to live load temperature, laboratory testing samples material properties high-stress low-cycle characteristics, as well development an effective based analytical, experimental,...