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Modern data sources and techniques for analysis and forecast of road accidents:A review

Journal of Traffic and Transportation Engineering(English Edition) 2020年第4期7卷 432-446页

作者： Camilo gutierrez-Osorio Cesar Pedraza Departamento de Ingeniena de Sistemas e Industrial Universidad Nacional de ColombiaBogotaColombia

Road accidents are one of the most relevant causes of injuries and death worldwide,and therefore,they constitute a significant field of research on the use of advanced algorithms and techniques to analyze and predict traffic accidents and determine the most relevant elements that contribute to road *** research of road accident prediction aims to respond to the challenge of offer tools to generate a more secure mobility environment,and ultimately,save *** paper aims to provide an overview of the state of the art in the prediction of road accidents through machine learning algorithms and advanced techniques for analyzing information,such as convolutional neural networks and long short-term memory networks,among other deep learning ***,in this article,a compendium and study of the most used data sources for the road accident forecast is *** a classification is proposed according to its origin and characteristics,such as open data,measurement technologies,onboard equipment and social media *** the analysis of the information,the different algorithms employed to make predictions about road accidents are listed and compared,as well as their applicability depending on the types of data being analyzed,along with the results obtained and their ease of interpretation and *** best results reported by the authors are obtained when two or more analytic techniques are combined,in such a way that analysis of the obtained results is *** the future challenges in road traffic forecasting lies the enhancement of the scope of the proposed models and predictions by the incorporation of heterogeneous data sources,that include geo spatial data,information from traffic volume,traffic statistics,video,sound,text and sentiment from social media,that many authors concur that can improve the precision and accuracy of the analysis and predictions.

关键词： Traffic engineering Data analysis Machine learning Road accident forecasting Traffic accident prediction

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Imprinting in plants

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Chinese Science Bulletin 2009年第14期54卷 2383-2389页

作者： gutierrez-MARCOS Jose Warwick HRI University of WarwickWellesbourneCV35 9EF UK

Genomic imprinting leads to the differential expression of parental alleles after fertilization. Imprinting appears to have evolved independently in mammals and flowering plants to regulate the development of nutrient-transfer placental tissues. In addition, the regulation of imprinting in both mammals and flowering plants involves changes in DNA methylation and histone methylation, thus suggesting that the epigenetic signals that regulate imprinting have been co-opted in these distantly related species.

关键词：开花植物 DNA甲基化基因组印记哺乳类动物差异表达基因胎盘组织养分转移信号调节

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Effect of surface loading on the hydro-mechanical response of a tunnel in saturated ground

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Underground Space 2016年第1期1卷 1-19页

作者： Simon Heru Prassetyo Marte gutierrez Department of Civil and Environmental Engineering Colorado School of MinesGoldenCO 80401USA

The design of underground spaces in urban areas must account not only for the current overburden load but also for future surface loads,such as from construction of high-rise buildings above underground *** saturated ground,the surface load will generate an additional mechanical response through stress changes and ground displacement,as well as a hydraulic response through pore pressure *** hydro-mechanical(H-M)changes can severely influence tunnel *** paper examines the effect of surface loading on the H-M response of a typical horseshoe-shaped tunnel in saturated *** tunnel models were created in the computer code Fast Lagrangian Analysis of Continua(FLAC).One model represented weak and low permeability ground(stiff clay),and the other represented strong and high permeability ground(weathered granite).Each of the models was run under two liner permeabilities:permeable and *** main cases were *** Case 1,the surface load was applied 10 years after tunnel *** Case 2,the surface load was applied after the steady state pore pressure condition was *** simulation results show that tunnels with impermeable liners experienced the most severe influence from the surface loading,with high pore pressures,large inward displacement around the tunnels,and high bending moments in the *** addition,the severity of the response increased toward steady *** induced H-M response was worse for tunnels in clay than for those in ***,the long-term liner stabilities in Case 1 and Case 2 were similar,indicating that the influence of the length of time between when the tunnel was completed and when the surface load was applied was *** findings suggest that under surface loading,in addition to the ground strength,tunnel stability in saturated ground is largely influenced by liner permeability and the long-term H-M response of the ground.

关键词： Surface loading Hydro-mechanical response Urban tunnels Saturated ground

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Axisymmetric alternating direction explicit scheme for efficient coupled simulation of hydro-mechanical interaction in geotechnical engineering-Application to circular footing and deep tunnel in saturated ground

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第2期10卷 259-279页

作者： Simon Heru Prassetyo Marte gutierrez Department of Civil and Environmental Engineering Colorado School of MinesGoldenUSA Mining Engineering Program Institut Teknologi BandungBandungIndonesia

Explicit solution techniques have been widely used in geotechnical engineering for simulating the coupled hydro-mechanical(H-M) interaction of fluid flow and deformation induced by structures built above and under saturated ground, i.e. circular footing and deep tunnel. However, the technique is only conditionally stable and requires small time steps, portending its inefficiency for simulating large-scale H-M problems. To improve its efficiency, the unconditionally stable alternating direction explicit(ADE)scheme could be used to solve the flow problem. The standard ADE scheme, however, is only moderately accurate and is restricted to uniform grids and plane strain flow conditions. This paper aims to remove these drawbacks by developing a novel high-order ADE scheme capable of solving flow problems in nonuniform grids and under axisymmetric conditions. The new scheme is derived by performing a fourthorder finite difference(FD) approximation to the spatial derivatives of the axisymmetric fluid-diffusion equation in a non-uniform grid configuration. The implicit Crank-Nicolson technique is then applied to the resulting approximation, and the subsequent equation is split into two alternating direction sweeps,giving rise to a new axisymmetric ADE scheme. The pore pressure solutions from the new scheme are then sequentially coupled with an existing geomechanical simulator in the computer code fast Lagrangian analysis of continua(FLAC). This coupling procedure is called the sequentially-explicit coupling technique based on the fourth-order axisymmetric ADE scheme or SEA-4-AXI. Application of SEA-4-AXI for solving axisymmetric consolidation of a circular footing and of advancing tunnel in deep saturated ground shows that SEA-4-AXI reduces computer runtime up to 42%-50% that of FLAC’s basic scheme without numerical instability. In addition, it produces high numerical accuracy of the H-M solutions with average percentage difference of only 0.5%-1.8%.

关键词： Hydro-mechanical(H-M) interaction Explicit coupling technique Alternating direction explicit(ADE) scheme High-order finite difference(FD) Non-uniform grid Axisymmetric consolidation Circular footing Deep tunnel in saturated ground

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UNCONDITIONAL CAUCHY SERIES AND UNIFORM CONVERGENCE ON MATRICES

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Chinese Annals of Mathematics,Series B 2004年第3期25卷 335-346页

作者： A.AIZPURU A.gutierrez-DAVILA DepartarnentodeMatematicas UniversidaddeCadizApdo.4011510-PuertoReal（Cadiz）Spain DepartamentodeMatematicas UniversidaddeCadizApdo.4011510-PuertoReal（Cadiz）Spain

The authors obtain new characterizations of unconditional Cauchy series in terms of separation properties of subfamilies of p(N), and a generalization of the Orlicz-Pettis Theorem is also obtained. New results on the uniform convergence on matrices and a new version of the Hahn-Schur summation theorem are proved. For matrices whose rows define unconditional Cauchy series, a better sufficient condition for the basic Matrix Theorem of Antosik and Swartz, new necessary conditions and a new proof of that theorem are given.

关键词： Unconditional Cauchy series Orlicz-Pettis theorem Summation Hahn-Schur theorem Basic matrix theorem

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Effectiveness of predicting tunneling-induced ground settlements using machine learning methods with small datasets

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第4期14卷 1028-1041页

作者： Linan Liu Wendy Zhou Marte gutierrez Department of Geology and Geological Engineering Colorado School of MinesGoldenCO80401USA Department of Civil and Environmental Engineering Colorado School of MinesGoldenCO80401USA

Prediction of tunneling-induced ground settlements is an essential task,particularly for tunneling in urban *** settlements should be limited within a tolerable threshold to avoid damages to aboveground *** learning(ML)methods are becoming popular in many fields,including tunneling and underground excavations,as a powerful learning and predicting ***,the available datasets collected from a tunneling project are usually small from the perspective of applying ML *** ML algorithms effectively predict tunneling-induced ground settlements when the available datasets are small?In this study,seven ML methods are utilized to predict tunneling-induced ground settlement using 14 contributing factors measured before or during tunnel *** methods include multiple linear regression(MLR),decision tree(DT),random forest(RF),gradient boosting(GB),support vector regression(SVR),back-propagation neural network(BPNN),and permutation importancebased BPNN(PI-BPNN)*** methods except BPNN and PI-BPNN are shallow-structure ML *** effectiveness of these seven ML approaches on small datasets is evaluated using model accuracy and *** model accuracy is measured by the coefficient of determination(R2)of training and testing datasets,and the stability of a learning algorithm indicates robust predictive ***,the quantile error(QE)criterion is introduced to assess model predictive performance considering underpredictions and *** study reveals that the RF algorithm outperforms all the other models with the highest model prediction accuracy(0.9)and stability(3.0210^(-27)).Deep-structure ML models do not perform well for small datasets with relatively low model accuracy(0.59)and stability(5.76).The PI-BPNN architecture is proposed and designed for small datasets,showing better performance than typical *** important contributing factors of ground settlements are identified,including

关键词： Ground settlements Tunneling Machine learning Small dataset Model accuracy Model stability Feature importance

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Physical model simulation of rock-support interaction for the tunnel in squeezing ground

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第1期14卷 82-92页

作者： Ketan Arora Marte gutierrez Ahmadreza Hedayat Civil and Environmental Engineering Colorado School of MinesGoldenCO80401USA

The existence of squeezing ground conditions can lead to significant challenges in designing an adequate support system for *** empirical,observational and analytical methods have been suggested over the years to design support systems in squeezing ground conditions,but all of them have some *** this study,a novel experimental setup having physical model for simulating the tunnel boring machine(TBM)excavation and support installation process in squeezing clay-rich rocks is *** observations are made to understand better the interaction between the support and the squeezing *** physical model included a large true-triaxial cell,a miniature TBM,laboratoryprepared synthetic test specimen with properties similar to natural mudstone,and an instrumented cylindrical aluminum support *** were conducted at realistic in situ stress levels to study the time-dependent three-dimensional tunnel support *** tunnel was excavated using the miniature TBM in the cubical rock specimen loaded in the true-triaxial cell,after which the support was *** confining stress was then increased in stages to values greater than the rock’s unconfined compressive strength.A model for the time-dependent longitudinal displacement profile(LDP)for the supported tunnel was proposed using the tunnel convergence measurements at different times and stress *** LDP formulation was then compared with the unsupported model to calculate the squeezing amount carried by the *** increase in thrust in the support was backcalculated from an analytical solution with the assumption of linear elastic *** on the test results and case studies,a recommendation to optimize the support requirement for tunnels in squeezing ground is proposed.

关键词： Squeezing ground Tunnel support system Longitudinal displacement profile Rock-support interaction

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Systemic Inflammation Response Index and weight loss as prognostic factors in metastatic pancreatic cancer: A concept study from the PANTHEIA-SEOM trial

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World Journal of Gastrointestinal Oncology 2024年第2期16卷 386-397页

作者： Vilma Pacheco-Barcia Sara Custodio-Cabello Fatima Carrasco-Valero Magda Palka-Kotlowska Axel Mariño-Mendez Alberto Carmona-Bayonas Javier Gallego A J Muñoz Martín Paula Jimenez-Fonseca Luis Cabezon-gutierrez Department of Medical Oncology Hospital Universitario de TorrejonMadrid 28850Spain Department of Internal Medicine Hospital Universitario de TorrejonMadrid 28850Spain Department of Medical Oncology Hospital Universitario Central de AsturiasOviedo 33011Spain Department of Medical Oncology Hospital Universitario Morales MeseguerUniversity of MurciaMurcia 30001Spain Department of Medical Oncology Hospital General Universitario de ElcheElche 03202Spain Department of Medical Oncology Hospital General Universitario Gregorio MarañónUniversidad Complutense MadridMadrid 28007Spain Universidad Francisco de Vitoria Madrid 28223Spain

BACKGROUND The prognostic value of the Systemic Inflammation Response Index(SIRI)in advanced pancreatic cancer is recognized,but its correlation with patients´nutritional status and outcomes remains *** To study the prognostic significance of SIRI and weight loss in metastatic pancreatic *** The PANTHEIA-Spanish Society of Medical Oncology(SEOM)study is a multicentric(16 Spanish hospitals),observational,longitudinal,non-interventional initiative,promoted by the SEOM Real World-Evidence work *** pilot study sought to analyze the association between weight loss and inflammatory status as defined by *** cohort stems from a proof-of-concept pilot study conducted at one of the coordinating *** with pathologically confirmed metastatic pancreatic adenocarcinoma,treated from January 2020 to January 2023,were *** index was calculated using the product of neutrophil and monocyte counts,divided by lymphocyte counts,obtained within 15 days before initiation *** study evaluated associations between overall survival(OS),SIRI and weight *** A total of 50 patients were included.66%of these patients were male and the median age was 66 *** sites:36%liver,12%peritoneal carcinomatosis,10%lung,and 42%multiple *** the first line palliative chemotherapy treatments:50%received gemcitabine plus nab-paclitaxel;28%,modified fluorouracil,leucovorin,irinotecan and oxaliplatin,and 16%were administered gemcitabine.42%had a weight loss>5%in the three months(mo)preceding diagnosis.21 patients with a SIRI≥2.3×10^(3)/L exhibited a trend towards a lower median OS compared to those with a SIRI5%weight loss before diagnosis,the median OS was 6 mo,in contrast to 19 mo for those who did not experience such weight loss(P=0.003).Patients with a weight loss>5%showed higher SIRI *** difference was statistically significant(P<0.000).For pat

关键词： Pancreatic cancer Nutrition Prognostic factor Inflammation Advanced cancer Systemic inflammatory response index Weight loss

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Solving Delay Differential Equations through RBF Collocation

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Advances in Applied Mathematics and Mechanics 2009年第2期1卷 257-272页

作者： Francisco Bernal Gail gutierrez Institute for Scientific Computing Technical University of Dresden 01062 DresdenGermany Cir 1 No.73-34 Instituto de Energia y TermodinamicaUniversidad Pontificia BolivarianaMedellinColombia

A general and easy-to-code numerical method based on radial basis functions(RBFs)collocation is proposed for the solution of delay differential equations(DDEs).It relies on the interpolation properties of infinitely smooth RBFs,which allow for a large accuracy over a scattered and relatively small discretization ***’s multiquadric is chosen as RBF and combined with the Residual Subsampling Algorithm of Driscoll and Heryudono for support *** performance of the method is very satisfactory,as demonstrated over a cross-section of benchmark DDEs,and by comparison with existing general-purpose and specialized numerical schemes for DDEs.

关键词： Meshless method delay differential equations radial basis function multiquadric adaptive collocation

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Stress-dependent shear wave splitting and permeability in fractured porous rock

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第1期11卷 1-11页

作者： Daisuke Katsuki Marte gutierrez Abdulhadi Almrabat Petroleum Engineering Department Colorado School of Mines Department of Civil and Environmental Engineering Colorado School of Mines

It is well known that shear wave propagates slower across than parallel to a fracture, and as a result, a travelling shear wave splits into two directions when it encounters a fracture. Shear wave splitting and permeability of porous rock core samples having single fracture were experimentally investigated using a high-pressure triaxial cell, which can measure seismic shear wave velocities in two directions mutually perpendicular to the sample axis in addition to the longitudinal compressive wave velocity. A single fracture was created in the samples using a modified Brazilian split test device, where the cylindrical sample edges were loaded on two diametrically opposite lines by sharp guillotines along the sample length. Based on tilt tests and fracture surface profilometry, the method of artificially induced tensile fracture in the sample was found to create repeatable fracture surfaces and morphologies. Seismic velocities of the fractured samples were determined under different levels of stress confinement and fracture shear displacement or mismatch. The effective confining stress was varied from 0.5 MPa to55 MPa, while the fractures were mismatched by 0 mm, 0.45 mm and 1 mm. The degree of matching of the fracture surfaces in the core samples was evaluated using the joint matching coefficient(JMC). Shear wave splitting, as measured by the difference in the magnitudes of shear wave velocities parallel(V_(S1))and perpendicular(V_(S2)) to the fracture, is found to be insensitive to the degree of mismatching of the fracture joint surfaces at 2 MPa, and decreased and approached zero as the effective stress was *** models for the stress-and JMC-dependent shear wave splitting and fractured rock permeability were developed based on the experimental observations. The effects of the joint wall compressive strength(JCS), JMC and stress on the stress dependency of joint aperture were discussed in terms of hydro-mechanical response. Finally, a useful relationship

关键词： Fractured rock Sandstone Stress dependency Shear wave splitting Wave velocity Permeability Fracture stiffness Elastic modulus

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