Generating realizations of the permeability field drawn from a probability density function conditioned on inaccurate pressure or saturation data is difficult, even if unconditional are Gaussian random fields, because problem highly nonlinear. Inefficient methods that generate large numbers rejected images, such as simulated annealing, must be ruled out impractical repeated need for reservoir flow simulation.

Debris flow, the most extensive and severe geological hazard along Karakoram Highway, frequently blocks Highway. Based on methods of field measurement, indoor statistical analysis theoretical research, this paper discusses relationship between four types debris flow The are rain type, glacier ice lake break type freeze–thaw their particle characteristics gully slope also considered in discussion. results as follows: (1) provenance size is controlled by flow. Generally, average equivalent...

The frequency of mudflow disasters induced by rainfall in the Loess Plateau is increasing with occurrence global warming. initial water content one basic properties soil, which affects initiation loess mudflow. In this work, field study debris flow gullies Yan’an City, Shaanxi Province, China, was conducted, and main factors that induce gully were summarized. Based on investigation results, a flume model designed to carry out tests different soil contents. experimental results demonstrate...

Abstract Elevated water tanks are considered crucial infrastructure due to their significant role in supporting essential services. A strong ground motion may result a failure or damage reinforced concrete shaft of an elevated tank because hysteric energy dissipation is limited the formation plastic hinges at base shaft, while nonlinear properties rest remain underutilised. The innovative system assembling RC shafts for using slit wall technique was developed enhance along with height by...

In order to improve the effectiveness of coal mine gas control and enhance level safety production, application a microseismic monitoring system hydraulic fracturing technology in mines was studied. Applying treatment, firstly, geological structure concentration mining area are detected using radio tunnel perspective method infrared differential absorption method. Then, relevant parameters determined, finally, is implemented. Microseismic used monitor cracks formed during construction...

Assessments of highway feasibility frequently lack the detailed data and geological information necessary to conduct hazard evaluations debris flows. This study discusses processes flow development when regional rainfall meets critical level required for initiation. It utilizes geomorphic evolution theory establishes a risk assessment matrix by combining about gullies source sensitivity. Considering location relationship between gullies, rapid evaluation method along G318 in Sichuan Province...

The intricate morphology of porous media can considerably affect the progression penetration and diffusion grouting slurry. In this study, a Newtonian fluid’s refined seepage motion equation was proposed to incorporate impact tortuosity on process into gravel soil, column-hemispherical mechanism analyzed using method theoretical analysis. Utilizing secondary-development programming techniques, numerical simulation program developed with COMSOL Multiphysics model fluid in pattern, considering...

During the construction of a diversion tunnel, geological problems often include faults, fragile strata, hard rock formations, karst landforms, etc., which may have adverse effects on excavation and tunnel. Based analysis engineering overview, this study designed new technology for water tunnels in layers high-karst areas. tunnel seismic prediction (TSP) to achieve advanced prediction, combined with actual conditions, difficulties are analyzed. Then, detection is used collect two-way travel...

We report the results of a study Qionghai Lake watershed, located on southeastern edge Qinghai–Tibetan Plateau, China, designed to investigate effects human activity changes in soil erosion intensity, debris flow and lacustrine sedimentation. The indicate that mean denudation rate watershed was about 0.82 mm/yr during Holocene. However, since 1952, has increased 1.82 mm/yr, accompanied by greatly sedimentation Lake. increases population related intensified exploitation land resources,...

Taking the Niumian Gully landslide–debris-flow geohazard chain as an example, we analyze disaster mechanism of and its evolution process through field investigation a reference for prevention risk reduction in areas with strong earthquakes by analyzing accumulative sliding amount critical rainfall debris flow formed loose deposits. Due to 8.0 Ms earthquake Wenchuan, cumulative slope reached 230.51 m, much greater than Longmen Mountain area. Permanent damage occurred, resulting landslide,...

The diffusion progress of grout is hindered by groundwater, which means the distance cannot reach designed values required in engineering for water plugging or reinforcement. In this study, based on generalized Darcy’s law and continuity equation steady column penetration, a mechanism Bingham fluid, considering displacement effect proposed. This then validated penetration grouting experiments that have been previously performed. influences pressure, groundwater water–cement ratio coefficient...

In recent years, debris flow disasters have occurred frequently along the highway, causing river blockages and road interruptions, which seriously threaten safety of people's lives property. Highway G318 is an important throat project linking Sichuan Tibet; at same time, it channel for economic development Tibet transportation national defense materials. Taking Linzhi–Lhasa Section as example, this study analyses distribution law characteristics coupling factors flows in area (under its...

Abstract Scientifically defining the scope of mountain distribution and understanding spatial patterns mountainous areas in China is critical for formulating development policies tailored to diverse needs different regions promoting rural revitalization areas. This study aims scientifically define understand pattern characteristics aid formulation differentiated support strategies Using measurements mountains hills Mainland China, drawing on European scholars' definitions cities, a...

Considering the limitations of current pavement crack damage detection methods, this study proposes a method based on digital image processing technology for detecting highway asphalt damage. Firstly, non-subsampled contourlet transform is used to enhance pavement. Secondly, non-crack regions in are screened, and extraction completed by obtaining enhancing intensity map. Finally, features cracks extracted input into support vector machine classification recognition complete The experimental...

With the continuous increase in global climate change and human activities, risk of sudden debris flow disasters is becoming increasingly severe. In order to effectively evaluate zone potential hazards flows, this paper proposes a method for zoning flows based on deep neural networks. According hazard identification, ten indicators are determined. The each region were used as input factors trust network (DBN) composed back propagation (BP) restricted Boltzmann machine (RBM). DBN pre-trained...

The sedimentation basin is an important part of hydraulic engineering. Because the prototype size too large and not easy to analyze, Mike 21 has advantages input, conversion, analysis, demonstration data results, which are flexible convenient; however, this method been used in engineering by previous researchers. This research Yellow River Diversion Project as object, a simulation model channel #1 was developed using software analyze its water sediment characteristics conditions different...

Abstract. Aerosol samples (TSP, n=58) were collected on day- and night-time basis at Mangshan in the north of Beijing, China autumn 2007 to better understand status air quality influence urban pollutants northern vicinity Beijing. The analyzed for aerosol mass, total carbon (TC), low molecular weight α, ω-dicarboxylic acids (C2-C12), ketoacids (ωC2-ωC9, pyruvic acid), α-dicarbonyls (glyoxal methylglyoxal), as well aromatic (phthalic, iso- tere-phthalic) diacids. mass TC concentrations are...

By means of the Graphic Method, Gray Correlation Method and Frequency total amount loose solid materials, materials per unit area in source area, risk degree critical rainfall study are determined, respectively. On basis calculation results, is 57.2 × 10 4 m 3 , 0.13 /m 2 (greater than 0.1 ), which better meets initiation conditions for dilute debris flow. The Hazard Evaluation Model Debris Flow earthquake areas established by gray correlation method hazard index H = 0.725 determined....

Abstract To investigate the origins, other than fossil fuel combustion and biomass burning, of urban carbonaceosus aerosols, we studied fine (PM 2.5 ) aerosols collected in Guiyang, Southwest China winter (December 10–23) 2012 for organic carbon (OC), elemental (EC) water-soluble diacids, oxoacids, α -dicarbonyls fatty acids as well inorganic ions. Oxalic acid (C 2 found to be most abundant diacid species followed by succinic 4 terephthalic ( t -Ph) acids, respectively. Even-carbon numbered...

Objective: To establish an asymmetric U-shaped response relationship between urinary iodine level and thyroid nodule prevalence. Methods: Taking "Iodine" "Urine Iodine" "Thyroid" "Thyroid Nodule" as Chinese keywords, "Goiter" English literatures about urine prevalence were searched in China Biology Medicine disc, National Knowledge Internet, Wanfang Data, PubMed Springer databases from January 2000 to December 2019 respectively. The language of was restricted English. There 46 articles (24...