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Vehicle and pedestrian safety impacts of signal timing optimization in a dense urban street network

Journal of Traffic and Transportation Engineering(English Edition) 2016年第1期3卷 16-27页

作者： Arash M.Roshandeh Zongzhi Li shengrui Zhang herbert s.leuinson Xi Lu Department of Engineering and Public Works City of AlpharettaGA 30009USA Department of civil Architectural and Environmental Engineeringillinois Institute of TechnologyChicagoIL 60616USA school of Highway Chang'an UniuersityXi'an 710064China herbert s.leuinson Transportation Consultant New HauenCT 06492USA

Intersection signal timing optimization is expected to affect both traffic mobility and safety. However, in safety impacts analysis, the existing studies mainly focus on estimating changes in vehicle crashes without addressing the influence of pedestrian related crashes. This study aims to simultaneously assess the overall impacts of vehicle and pedestrian crashes caused by signal timing optimization in dense urban street networks. An empirical Bayesian analysis method was introduced to estimate the safety impacts of intersection signal timing optimization in an urban street network in terms of vehicle-tovehicle and vehicle-to-pedestrian crashes at intersections, as well as single and multiple vehicle crashes on street segments. A computational experiment was performed to apply the proposed method to the Chicago central business district that includes 875 signalized intersections and 2016 roadway segments. Results show that vehicle-to-vehicle and vehicle-to-pedestrian crashes at intersections are decreased in different crash severity levels and types, especially for angle and rear-end ones after signal timing optimization. similar results are found for multi-vehicle rear-end crashes on street segments. These indicate that intersection signal timing optimization in dense urban street networks has a potential for improving traffic mobility, vehicle and pedestrian safety at intersections, and vehicle safety on street segments.

关键词： signalOptimizationsafetyVehiclePedestrianEmpirical Bayesian analysis

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synthesis of Fréchet-type dendritic homotriptycenes

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science China Chemistry 2009年第7期52卷 1051-1056页

作者： MEIER herbert school of Chemistry and Chemical Engineering South China University of Technology Institute of Organic Chemistry University of Mainz

A rapid and efficient synthesis of novel dendrimer homotriptycenes is presented. The dendronized 9,10-dihydroanthracen-9-ols 4, having high electron densities in the benzene rings of the Fréchet-type dendrons, exhibited in the presence of acid a quantitative transannular ring closure to the corresponding dendritic homotriptycenes. The electron-donating Fréchet-type dendrons enabled the intramolecular FC alkylation by a regioselective 1,7-elimination of H2O.

关键词： carbenium ions dendrimers ring closure reaction triptycene homotriptycene

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Characterization of VAMP-2 gene from marine teleostean,Lateolabrax japonicus

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science China(Life sciences) 2006年第6期49卷 591-596页

作者： Gaisano herbert Department of Medicine and Physiology University of Toronto

The whole length sPV2 gene of 715 bp, encoding VAMP-2 protein of 110 amino acids from Japanese sea perch, Lateolabrax japonicus, was obtained by using both RT-PCR; anchored PCR strategies while we initiated the structural; functional study on sNARE proteins in marine teleostean. Analysis of the deduced amino acid sequence indicated that sPV2 has its core arginine residue, a potential N-linked glycosylation site near its N-terminal,; one transmembrane domain in its C-terminal. Advanced structural analysis of bioinformatics approach predicts a coiled-coil α-helix backbone as the characteristic of sPV2 main conformational structure, identical to the structure of rat VAMP-2 obtained by crystallography. semi-quantitative RT-PCR revealed that sPV2 was generally expressed in 10 neural; non-neural tissues, with the highest concentration in brain; the least in muscle.

关键词： Lateolabrax japonicus, VAMP-2, sNARE, cloning, sequence analysis.

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GREEN's FUNCTIONs OF INTERNAL ELECTRODEs BETWEEN TWO DIssIMILAR PIEZOELECTRIC MEDIA

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Applied Mathematics and Mechanics(English Edition) 2005年第2期26卷 234-241页

作者：高存法 herbert Balke Institute of solid Mechanics Dresden University of Technology 01062 Dresden Germany

The generalized 2-D problem of a half-infinite interfacial electrode layer between two arbitrary piezoelectric half-spaces is studied. Based on the stroh formalism, exact expressions for the (Green's) functions of a line force, a line charge and a line electric dipole applied at an arbitrary point near the electrode edge,were presented, respectively. The corresponding solutions for the intensity factors of fields were also obtained in an explicit form. These results can be used as the foundational solutions in boundary element method (BEM) to solve more complicated fracture problems of piezoelectric composites.

关键词： piezoelectric material internal electrode Green's function coupled field

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Efficient Reconstruction Methods for Nonlinear Elliptic Cauchy Problems with Piecewise Constant solutions

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Advances in Applied Mathematics and Mechanics 2009年第6期1卷 729-749页

作者： herbert Egger Antonio Leitao MathCCEs Aachen University52062 AachenGermany Department of Mathematics Federal University of St.CatarinaP.O.Box 47688040-900 Florian´opolisBrazil

In this article,a level-set approach for solving nonlinear elliptic Cauchy problems with piecewise constant solutions is proposed,which allows the definition of a Tikhonov functional on a space of level-set *** provide convergence analysis for the Tikhonov approach,including stability and convergence ***,a numerical investigation of the proposed Tikhonov regularization method is ***-type methods are used for the solution of the optimality systems,which can be interpreted as stabilized versions of algorithms in a previous work and yield a substantial improvement in *** whole approach is focused on three dimensional models,better suited for real life applications.

关键词： Nonlinear Cauchy problems Elliptic operators Level-set methods

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Assessment of GNss zenith tropospheric delay responses to atmospheric variables derived from ERA5 data over Nigeria

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satellite Navigation 2023年第1期4卷 167-182,I0005页

作者： Ifechukwu Ugochukwu Nzelibe herbert Tata Timothy Oluwadare Idowu Department of surveying and Geoinformatics Federal University of Technology AkureAkureNigeria

Tropospheric delay is a major error caused by atmospheric refraction in Global Navigation satellite system(GNss)*** study evaluates the potential of the European Centre for Medium-range Weather Forecast(ECMWF)Reanalysis 5(ERA5)atmospheric variables in estimating the Zenith Tropospheric Delay(ZTD).Linear regression models(LRM)are applied to estimate ZTD with the ERA5 atmospheric *** ZTD are also estimated using standard ZTD models based on ERA5 and Global Pressure and Temperature 3(GPT3)atmospheric *** ZTD estimates are evaluated using the data collected from the permanent GNss continuously operating reference stations in the Nigerian *** results reveal that the Zenith Hydrostatic Delay(ZHD)from the LRM and the saastamoinien model using ERA5 surface pressure are of identical accuracy,having a Root Mean square(RMs)error of 2.3 mm while the GPT3-ZHD has an RMs of 3.4 *** the Zenith Wet Delay(ZWD)component,the best estimates are derived using ERA5 Precipitable Water Vapour(PWV).These include the ZWD derived by the LRM having an average RMs of 20.9 mm and Bevis equation having RMs of 21.1 mm and 21.0 mm for global and local weighted mean temperatures,*** evaluation of GPT3-ZWD estimates gives RMs of 45.8 *** study has provided a valuable insight into the application of ERA5 data for ZTD *** line with the fndings of the study,the ERA5 atmospheric variables are recommended for improving the accuracy in ZTD estimation,required for GNss positioning.

关键词： ECMWF reanalysis 5(ERA5) Global navigation satellite systems(GNss) Global pressure and temperature 3(GPT3) Modelling Nigeria Zenith tropospheric delay(ZTD)

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Hazard potential of zones of weakness in gravity dams under impact loading conditions

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Frontiers of structural and Civil Engineering 2011年第1期5卷 90-97页

作者： herbert LINsBAUER Institute of Hydraulic Engineering and Water Resources Management Vienna University of TechnologyViennaAustria

Dam constructions worldwide are designed and constructed in view of the strictest safety aspects for all static and dynamic load *** experience shows,however,formation of cracks in the“homogeneos concrete”as well as unsatisfactory compound behavior of lift joints are not to be *** zones of weakness especially on the upstream side of the dam-exposed to high water pressure(static and dynamic)-represent an increased risk of *** main investigation,apart from the computation of the dynamic effects on the dam as a global structure,focuses on the stability analysis of a pressure-water filled crack configuration subjected to“dynamic loading”in the form of seismic action on the dam-reservoir-system and alternatively by“impact spot-loading”within sectors of the reservoir.A fracture mechanics based analysis shows an excessive potential of damage for the afflicted structure.

关键词： dam-reservoir earthquake impact cracking fracture mechanics

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Benchmarking visual sLAM methods in mirror environments

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Computational Visual Media 2024年第2期10卷 215-241页

作者： Peter herbert Jing Wu Ze Ji Yu-Kun Lai school of Computer science and Informatics Cardiff UniversityAbacws BuildingSenghennydd RdCardiff CF244AGUK school of Engineering Cardiff UniversityQueen’s BuildingsThe ParadeCardiff CF243AAUK

Visual simultaneous localisation and mapping(vsLAM)finds applications for indoor and outdoor navigation that routinely subjects it to visual complexities,particularly mirror *** effect of mirror presence(time visible and its average size in the frame)was hypothesised to impact localisation and mapping performance,with systems using direct techniques expected to perform ***,a dataset,MirrEnv,of image sequences recorded in mirror environments,was collected,and used to evaluate the performance of existing representative *** ORB-sLAM3 and BundleFusion appear to show moderate degradation of absolute trajectory error with increasing mirror duration,whilst the remaining results did not show significantly degraded localisation *** mesh maps generated proved to be very inaccurate,with real and virtual reflections colliding in the reconstructions.A discussion is given of the likely sources of error and robustness in mirror environments,outlining future directions for validating and improving vsLAM performance in the presence of planar *** MirrEnv dataset is available at https://***/10.17035/d.2023.0292477898.

关键词： visual simultaneous localisation and mapping(vsLAM) mirror localisation mapping reflection datase

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Molecular dynamics simulation of the stribeck curve: Boundary lubrication, mixed lubrication, and hydrodynamic lubrication on the atomistic level

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Friction 2023年第12期11卷 2342-2366页

作者： simon sTEPHAN sebastian sCHMITT Hans HAssE herbert M.URBAssEK Laboratory of Engineering Thermodynamics(LTD) Department of Mechanical and Process EngieeringTU KaiserslauternRheinland-Pfalz 67663Germany Physics Department and Research Center(OPTIMAs) TU KaiserslauternRheinland-Pfalz 67663Germany

Lubricated contact processes are studied using classical molecular dynamics simulations for determining the entire range of the stribeck ***,the lateral movement of two solid bodies at different gap height are *** each simulation,a rigid asperity is moved at constant height above a flat iron surface in a lubricating *** methane and decane are considered as *** three main lubrication regimes of the stribeck curve and their transition regions are covered by the study:Boundary lubrication(significant elastic and plastic deformation of the substrate),mixed lubrication(adsorbed fluid layer dominates the process),and hydrodynamic lubrication(shear flow is set up between the surface and the asperity).We find the formation of a tribofilm in which lubricant molecules are immersed into the metal surface—not only in the case of scratching,but also for boundary lubrication and mixed *** formation of a tribofilm is found to have important consequences for the contact ***,the two fluids are found to show distinctly different behavior in the three lubrication regimes:For hydrodynamic lubrication(large gap height),decane yields a better tribological performance;for boundary lubrication(small gap height),decane shows a larger friction coefficient than methane,which is due to the different mechanisms observed for the formation of the tribofilm;the mixed lubrication regime can be considered as a transition regime between the two other ***,it is found that the nature of the tribofilm depends on the lubricant:While methane particles substitute substrate atoms sustaining mostly the crystalline structure,the decane molecules distort the substrate surface and an amorphous tribofilm is formed.

关键词： boundary lubrication mixed lubrication hydrodynamic lubrication molecular dynamics simulation tribofilm

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Clinical outcomes of combined versus separate carbachol and brimonidine drops in correcting presbyopia

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Eye and Vision 2016年第1期3卷 239-244页

作者： Almamoun Abdelkader herbert E.Kaufman Department of Ophthalmology Faculty of MedicineAl-Azhar UniversityCairoEgypt Department of Ophthalmology Louisiana State University Eye CenterLSU Medical SchoolNew OrleansLAUSA

Background:To test and compare in a masked fashion the efficacy of using a parasympathomimetic drug(3%carbachol)and an alpha-2 agonist(0.2%brimonidine)in both combined and separate forms to create optically beneficial miosis to pharmacologically improve vision in ***:A prospective,double-masked,randomized,controlled clinical trial was *** naturally emmetropic and presbyopic subjects between 42 and 58 years old with uncorrected distance visual acuity of at least 20/20 in both eyes without additional ocular pathology were eligible for *** subjects received 3%carbachol and 0.2%brimonidine in both combined and separate forms,3%carbachol alone and 0.2%brimonidine(control)alone in their non-dominant eye in a crossover manner with one week washout between *** subjects’pupil sizes and both near and distance visual acuities will be evaluated pre-and post-treatment at 1,2,4,and 8 h,by a masked examiner at the same room ***:statistically significant improvement in mean near visual acuity(NVA)was achieved in all subjects who received combined 3%carbachol and 0.2% brimonidine in the same formula compared with those who received separate forms or carbachol alone or brimonidine alone(Psion:Based on the data,the combined solution demonstrated greater efficacy than the other solutions that were *** the depth of focus by making the pupil small caused statistically significant improvement in near visual acuity,with no change in binocular distance *** registration:*** 11 November 2016.

关键词： Presbyopia Carbachol Brimonidine Depth of focus Miosis

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