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A SURVEY OF STACKELBERG DIFFERENTIAL GAME MODELS IN SUPPLY AND MARKETING CHANNELS

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j.urnal of Systems Science and Systems Engineering 2008年第2期17卷 255-255页

Erratum to: j.Syst Sci Syst EngDOI: 10.1007/s11518-007-5058-2The presentation of Table 2 in the original version of this article contained a few typos. The corrected Table 2 is given below.

关键词： OLS A SURVEY OF STACKELBERG DIFFERENTIAL GAME MODELS IN SUPPLY AND MARKETING CHANNELS rate

Bio-Imitation of Mexican Migration Routes to the USA with Slime Mould on 3D Terrains

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j.urnal of Bionic Engineering 2013年第2期10卷 242-250页

作者： Andrew Adamatzky genaro j.Martinez Department of Computer Sciences University of the West of England Bristol BS16 1QY UK Escuela Superior de Computo Instituto Politecnico Nacional Mexico

Plasmodium ofPhysarum polycephalum （P. polycephalum） is a large single cell visible by an unaided eye. It shows sophisticated behavioural traits in foraging for nutrients and developing an optimal transport network of protoplasmic tubes spanning sources of nutrients. When placed in an environment with distributed sources of nutrients the cell computes＇ an optimal graph spanning the nutrients by growing a network of protoplasmic tubes. P. polycephalum imitates development ofman-made transport networks of a country when configuration of nutrients represents maj.r urban areas, We employed this feature of the slime mould to imitate mexican migration to USA. The Mexican migration to USA is the World＇s larger migration system. We bio-physically imitated the migration using slime mould P. poIycephalum. In laboratory experiments with 3D Nylon terrains of USA we imitated development of migratory routes from Mexico-USA border to ten urban areas with high concentration of Mexican migrants. From results of laboratory experiments we extracted topologies of migratory routes, and highlighted a role of elevations in shaping the human movement networks.

关键词： biomimetics bio-inspired computing migration routes slime mould

Viscoelastic Burger’s model for tunnels supported with tangentially yielding liner

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j.urnal of Rock Mechanics and Geotechnical Engineering 2023年第4期15卷 826-837页

作者： Xiongyu Hu Marte gutierrez University Transportation Center for Underground Transportation Infrastructure Colorado School of MinesGoldenCO80401USA

This study proposed an analytical model for the tunnel supported with a tangentially yielding liner in viscoelastic *** efficiency of the developed analytical model was verified by comparing the calculated results with associated numerical simulation *** the analytical model,a comprehensive parameter sensitivity analysis was performed to examine the effects of the rate of tunnel face advancement,concrete liner thickness,installation time of liner,and strength and thickness of yielding elements on the tunnel *** results highlight the significant benefit of the tangentially yielding liner to relieve overstress in the tunnel liner and improve the stability of the *** yield efficiency of the tangentially yielding liner depends highly on the yielding strength and deformable capacity of the yielding elements and less on the installation time.

关键词： Viscoelastic Burger’s rock Deep tunnel Tangentially yielding liner Closed-form solution

Determination of a suitable set of loss models for centrifugal compressor performance prediction

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Chinese j.urnal of Aeronautics 2017年第5期30卷 1644-1650页

作者： Elkin I.gutierrez VELASQUEZ Faculty of Mechanical Engineering Universidad Antonio Narino Medellln 050012 Colombia

Performance prediction in preliminary design stages of several turbomachinery components is a critical task in order to bring the design processes of these devices to a successful conclusion. In this paper, a review and analysis of the maj.r loss mechanisms and loss models, used to determine the efficiency of a single stage centrifugal compressor, and a subsequent examination to determine an appropriate loss correlation set for estimating the isentropic efficiency in preliminary design stages of centrifugal compressors, were developed. Several semi-empirical correlations,commonly used to predict the efficiency of centrifugal compressors, were implemented in FORTRAN code and then were compared with experimental results in order to establish a loss correlation set to determine, with good approximation, the isentropic efficiency of single stage *** aim of this study is to provide a suitable loss correlation set for determining the isentropic efficiency of a single stage centrifugal compressor, because, with a large amount of loss mechanisms and correlations available in the literature, it is difficult to ascertain how many and which correlations to employ for the correct prediction of the efficiency in the preliminary stage design of a centrifugal compressor. As a result of this study, a set of correlations composed by nine loss mechanisms for single stage centrifugal compressors, conformed by a rotor and a diffuser, are specified.

关键词： Centrifugal compressor Efficiency loss Performance prediction Preliminary design Turbomachinery

3D printing of ABS *** of processing and effects of multi-wall and single-wall carbon nanotubes on thermal,mechanical and electrical properties

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j.urnal of Materials Science & Technology 2022年第26期121卷 52-66页

作者： Sithiprumnea Dul Brenda j.Alonso gutierrez Alessandro Pegoretti j.ime Alvarez-Quintana Luca Fambri Department of Industrial Engineering and INSTM Research Unit University of TrentoTrento 38123Italy Centro de Investigación en Materiales Avanzados S.C.Unidad MonterreyApodaca 66600Mexico Facultad de Ingeniería Mecánica y Eléctrica Universidad Autónoma de Nuevo LeónAvenida Universidad s/nCiudad UniversitariaSan Nicolás de los Garza 66451México

The following paper reports on a comparative study of the effects of two types of carbon nanotubes,namely multiwall(MWCNT)and single-wall(SWCNT)carbon nanotube,on the properties of 3D-printed parts produced with acrylonitrile-butadiene-styrene(ABS)nanocomposites with various CNT loadings of5-10 wt.%.Quasi-static tensile properties and Vicat softening temperature of 3D-printed parts were enhanced with the increasing CNT *** highest enhancement in tensile properties was observed for the ABS/CNT nanocomposites at 10 wt.%filler loading.3D-printed ABS/SWCNT composites showed higher tensile modulus,better creep stability and higher Vicat ***,the strength of ABS/SWCNT 3D samples is relatively lower than that of ABS/*** addition,3D-printed parts exhibited anisotropic electrical conductive behaviour,which has a conductivity of through-layer of about2-3 orders of magnitude higher than *** highest conductivity of 3D-printed samples reached25.2 S/m,and 9.3 S/m for ABS/MWCNT and ABS/SWCNT composites at 10 wt.%,*** results obtained,*** successful fuse filament fabrication and the consequent electromechanical properties,confirm that these 3D printable nanocomposite could be properly utilized for the production,and application up to about 90°C,of thermoelectric devices and/or resistors for flexible circuits.

关键词： Fuse filament fabrication Conductive polymers Nanocomposites Mechanical properties Creep behavior Resistivity

Coupled hydro-thermo-mechanical modeling of hydraulic fracturing in quasi-brittle rocks using BPM-DEM

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j.urnal of Rock Mechanics and Geotechnical Engineering 2017年第1期9卷 92-104页

作者： Ingrid Tomac Marte gutierrez Department of Structural Engineering University of California San Diego Department of Civil and Environmental Engineering Colorado School of Mines Department of Geosciences University of Oslo

This paper presents an improved understanding of coupled hydro-thermo-mechanical(HTM) hydraulic fracturing of quasi-brittle rock using the bonded particle model(BPM) within the discrete element method(DEM). BPM has been recently extended by the authors to account for coupled convective econductive heat flow and transport, and to enable full hydro-thermal fluidesolid coupled *** application of the work is on enhanced geothermal systems(EGSs), and hydraulic fracturing of hot dry rock(HDR) is studied in terms of the impact of temperature difference between rock and a flowing fracturing fluid. Micro-mechanical investigation of temperature and fracturing fluid effects on hydraulic fracturing damage in rocks is presented. It was found that fracture is shorter with pronounced secondary microcracking along the main fracture for the case when the convectiveeconductive thermal heat exchange is considered. First, the convection heat exchange during low-viscosity fluid infiltration in permeable rock around the wellbore causes significant rock cooling, where a finger-like fluid infiltration was observed. Second, fluid infiltration inhibits pressure rise during pumping and delays fracture initiation and propagation. Additionally, thermal damage occurs in the whole area around the wellbore due to rock cooling and cold fluid infiltration. The size of a damaged area around the wellbore increases with decreasing fluid dynamic viscosity. Fluid and rock compressibility ratio was found to have significant effect on the fracture propagation velocity.

关键词： Hydro-thermo-mechanical(HTM) modeling Enhanced geothermal systems(EGSs) Discrete element method(DEM) Bonded particle model(BPM) Conductive-convective heat flow and transport Hydraulic fracturing Rock permeability enhancement

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

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j.urnal 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 inj.ries 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

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

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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j.urnal 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