To provide a theoretical basis for the development of water hazard prevention schemes roof sandstone, this study systematically conducts uniaxial compression, acoustic emission, scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), and X-ray diffraction (XRD) tests on thick water-bearing sandstone at depths 623–943 m in Luohe Formation Binchang Mining Area, investigating its mechanical properties mechanisms micro-damage evolution under compression.The results indicate that...

Multi-baseline (MB) phase unwrapping (PU) is a key step of MB synthetic aperture radar (SAR) interferometry (InSAR). Compared with the traditional single-baseline (SB) PU, PU applicable to area where topography varies violently without obeying continuity assumption. A two-stage programming approach (TSPA) proposed by H. Yu. builds link between SB and PUs, so many existing classical methods can be transplanted into domain. In this paper, an extended max-flow/min-cut (PUMA) algorithm for InSAR...

Two non-homogeneous Poisson processes including the power law process and log-linear with reliability improvement or deterioration are analyzed. Based on Akaike information criterion Bayesian criterion, best model of failure data is presented. The point maximum likelihood interval estimators parameters, as well seven indices model, such cumulative mean time between failures, number at a given time, warranty given. In tests for trends, both graphical methods, failures versus plot...

In order to increase the accuracy and stability of classical response surface method relevant method, a new improved based on idea double weighting factors vector projection is proposed. The fitted by weighted regression technique, which allows sampling points be their distance from true failure that estimated design point. It uses gradient get in process iteration, make closer point, value deviation coefficient constantly adjusted. To some extent, these strategies while calculation time...

Phase unwrapping (PU) is one of the key processes in reconstructing digital elevation model a scene from its interferometric synthetic aperture radar (InSAR) data. It known that two-dimensional (2-D) PU problems can be formulated as maximum posteriori estimation Markov random fields (MRFs). However, considering traditional MRF algorithm usually defined on rectangular grid, it fails easily if large parts wrapped data are dominated by noise caused low-coherence area or rapid-topography...

Most current optimization methods could not take engineering and economical factors into account at the same time. A theoretical method, which obtain a simultaneous of economy, has been proposed on horizontal injection-production patterns with net present value (NPV) cumulative production as its target organisms. The theory wave frontal movement utilized to limit pattern scope pressure drawdown constraint from 0 three quarters formation fracture pressure. method is finally tried out in...

We utilize a tomography-based persistent scatterer interferometric synthetic aperture radar (Tomo-PSInSAR) approach for monitoring the deformation performance and analysis of thermal expansion 33 high-rise buildings in Shanghai Lujiazui. For purpose this study, we use 31 stripmap acquisitions from TerraSAR-X missions spanning December 2009 to February 2013. Considering that expansion, concrete creep, shrinkage are three long-term movements occur with structures, an extended 4-D SAR phase...

This paper presents research on the abutment forces of a double-curvature arch dam during overload based numerical calculation results obtained through finite element method by Ansys. Results show that, with an increase in elevation, and bending moment first then decrease from bottom to top dam. Abutment reach their maximum at middle or middle-down portion The distributions do not change overload. magnitude each layer’s increases linearly result indicates that layer transmits bearing loads...

Using the separation line technology, established a FE model of two-dimensional cutting process for AISI4340 steel and discussed some basic theory pivotal questions associated with simulation including Johnson-Cook material model, contact between tool chip, criteria chip so on. In order to study impact rake angle on morphology forces, high-speed AISI 4340 was simulated based ABAQUS software. Also, analyzed influence mesh azimuth its temperature distribution.

Aiming at the problem of big calculation error in solving reliability index by traditional response surface method, an improved method based on linear gradient iteration criterion is proposed. First, proposed to reduce step size with increase times. It will improve fitting accuracy and lead a better convergence while approaching limit state surface. Then, reduction coefficient iterative studied. The optimal value 0.2. get more accurate quickly. Examples show that has obvious advantages high...

Reinforced concrete (RC) bent structures are widely used in single-story industrial buildings, with a considerable portion of them located high-intensity seismic areas. Therefore, it is significant to study the performance RC column while keeping construction costs mind. To evaluate from an economic perspective, pseudo-static tests combined cost analysis were first carried out on three columns designed according different versions Chinese codes. A numerical simulation method based extended...

Adopt software Proe 5.0 to create model and processing technology planning of integral impeller, This paper is establish an NC plan integrated with modeling, programming, simulation optimization, taking the impeller as example combining CAM system 5-axis module Vericut7.15. By above plan, more proper method can be got, will improved, cost decrease. this users prolong service life cutter, improve surface quality, shorten production cycle enhance utilization rate productivity lathe. detailed...

We take into account to find a set of rapid evacuation routes during building fire.We construct three-dimensional structure the network, an route is sequence movements people away from threat fire, safe exit in network.The fire can stress crowds, cause their competitive behaviors, lead disorder and blocking as they pass through nearest passages exits.This paper provide novel improvement fruit fly (IFOA) algorithm for 3D with different node flow rate limiting characterizing.The has been...

To study the removal mechanism of materials during nano cutting, molecular dynamics method is adopted to simulate single crystal copper nanomachining processes, and subsurface defects evolvements chip forming regulation are analyzed by revised centro-symmetry parameter ratios tangential cutting force normal force. The results show that there different under depths. When depths shallower, dislocation loop nucleation in workpiece beneath tool; however, when deeper, dislocations slipping along...

The random response characteristic of weak nonlinear structure under biaxial earthquake excitation is investigated. has a SDOF (single degree freedom) with supporting braces and viscoelastic dampers. First, it adopts integral constitutive relation establishes differential equations motion. Then, according to the principle energy balance, equation linearized. Finally, based on stochastic averaging method, general analytical solution variance displacement velocity equivalent damping deduced...

Land cover classification from very high resolution (VHR) image (e.g. QuickBird, IKONOS) is an extremely challenging task due to spatial heterogeneity and low spectral separability. Markov random field (MRF) based methods have proven be effective for solving the above problem by integrating contextual information into process. Existing energy minimization approaches MRF-based model cannot balance accuracy computational efficiency. Focusing on efficient of model, we apply two graph cuts...

It does numerical analysis on the overload of RCC arch dam named wanjiakouzi, through analysis, we try to find damage process dam. elastic-plastic by FEM. Result shows that horizontal cracks are usually a very important symbol, it means will reach its ultimate capacity.