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Skid resistance performance and texture lateral distribution within the lanes of asphalt pavements

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Journal of Traffic and transportation Engineering（English Edition） 2021年

作者： Di Yun Liqun Hu Ulf Sandberg Cheng Tang School of Highway， Chang'an University Key Laboratory of Special Area Road Engineering of Ministry of Education， Chang'an University swedish national Road and Transport Research Institute (VTI) School of Civil Engineering and transportation， South China University of Technology

The skid resistance and pavement texture can vary a lot for different lane paths， meaning that the lateral shift of the vehicle driving in the lane section can affect the safety significantly. On the other hand， a varying skid resistance across a lane section provides the opportunity to influence vehicles to run in lateral positions where the tire/road friction has not yet been reduced by wear; thus， improving safety. This measure would be useful only if the distribution of skid resistance and pavement texture in the lane sections are investigated at frequent intervals. This study focused on four test sections on in-service urban roads. A friction measuring device known as the T2GO system was used to test the skid resistance performance of pavements for both dry and wet conditions. A high-precision 3D-scanner was used to capture the pavement macrotexture， and a microscope was employed to investigate the pavement abrasion. Subsequently， the effect of the lateral variation across the lane of friction and texture was discussed. The feasibility of displacing the vehicles to run in tracks with better skid resistance was explored in terms of the measured friction and the texture-dependent drainage capacity. The results indicated that driving closer to the lanes’ right side means that better values of friction， texture， and drainage parameters of the unworn pavement surface can be utilized. A 0.3 m or more lateral displacement would create improved friction， in a range between 13% and 14% for 1.5 m track width and between 8 and 11% for 1.65 m track width. Furthermore， the results are useful in studying the vehicles’ sideslip.

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Optimizing Emergency Logistics for the Offsite Hazardous Waste Management

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Journal of Systems Science and Systems Engineering 2019年第6期28卷 747-765页

作者： Jiahong Zhao Ginger Y.Ke School of Civil and transportation Engineering Guangdong University of TechnologyGuangzhou 510006China Faculty of Business administration Memorial University of NewfoundlandSt.John'sNewfoundland and LabradorCanada A1B 3X5

Hazardous wastes pose increasing threats to people and environment during the processes of offsite collection,storage,treatment,and disposal.A novel game theoretic model,including two levels,is developed for the corresponding optimization of emergency logistics,where the upper level indicates the location and capacity problem for the regulator,and the lower level reflects the allocation problem for the emergency *** from other works in the literature,we focus on the issue of multi-quality coverages (full and partial coverages) in the optimization of facility location and *** be specific,the regulator decides the location plan and the corresponding capacity of storing emergency groups for multiple types of hazmats,so to minimizes the total potential environmental risk posed by incident sites;while the commander minimizes the total costs to provide an efficient allocation *** solve the bi-level programming model,two solution techniques,namely a KKT condition approach and a heuristic model,are designed and *** proposed model and solution techniques are then applied to a hypothetical case and a real-world case to demonstrate the practicality and provide managerial insights.

关键词： Bi-level programming hazardous material time-based risk assessment multi-quality covering model KKT heuristic technique

Review and evaluation of cold recycling with bitumen emulsion and cement for rehabilitation of old pavements

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Journal of Traffic and transportation Engineering(English Edition) 2019年第4期6卷 311-323页

作者： Bohdan Dolzycki Piotr Jaskula Department of Highway and transportation Engineering Gdansk University of Technology

The article presents Polish experience with cold recycling of asphalt pavements with the usage of bituminous emulsion and cement. In the 1990 s numerous roads in Poland required immediate reinforcement due to their significant degradation. Implementation of the cold recycling technology was one of the solutions to this problem. Cold recycled mixtures contain e beside the recycled asphalt pavement and aggregate e two different types of binding agents: bituminous emulsion and Portland cement. First Polish requirements were developed in the 1990 s and were based on the Marshall test. After several years of application of these requirements, numerous transverse cracks appeared on the pavements. Field investigation showed that the frequency of transverse cracking was not uniform on all evaluated sections and that the growth rate of the number of cracks was decreasing. The main reason of extensive cracking was the overly high amount of the Portland cement and insufficient amount of the bituminous emulsion. This led to production of very stiff mixtures, with dominance of hydraulic bonds, which behaved similarly to cement-treated mixtures. The idea of flexible cold recycled base course was not utilized. This experience motivated the Polish Road administration to develop new requirements. Second part of the article presents the new requirements for cold *** test methods as well as requirements concerning resistance to frost and water action were introduced in 2013. Implementing of the new requirements resulted in significant reduction in stiffness of the MCE mixtures. Values of stiffness modulus are even three times lower, which should significantly decrease the amount of potential reflective cracks on the pavement surface. Presently two types of technology of cold recycling are used in Poland, in-place and in-plant.

关键词： Cold recycling Mineral-cement-emulsion mixtures(MCE) Reflecting cracks Stiffness modulus Road reconstruction Fatigue life of pavement structures

THE INVERSE PROBLEM OF KLEIN-GORDON EQUATION BOUNDARY VALUE PROBLEM AND ITS APPLICATION IN DATA ASSIMILATION

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Journal of Tropical Meteorology 2019年第1期25卷 92-101页

作者： MU Xi-yu XU Qi CHENG Hao SUN Kang-yuan XU Fen LIU Guo-qing Key Laboratory of transportation Meteorology China Meteorological Administration Jiangsu Institute of Meteorological Sciences Jiangsu Air Traffic Management Branch Bureau of CAAC School of Mathematical and Physical Sciences Nanjing Tech University

Since the solution of elliptic partial differential equations continuously depends on the boundary condition,the Euler equation derived from variational method cannot be solved without boundary condition. It is often difficult to provide the exact boundary condition in the practical use of variational method. However, in some application problems such as the remote sensing data assimilation, the values can be easily obtained in the inner region of the domain. In this paper, the boundary condition is tried to be retrieved by using part solutions in the inner area. Firstly, the variational problem of remote sensing data assimilation within a circular area is established. The Klein-Gordon elliptic equation is derived from the Euler method of variational problems with assumed boundary condition. Secondly, a computer-friendly Green function is constructed for the Dirichlet problem of two-dimensional Klein-Gordon equation, with the formal solution according to Green formula. Thirdly, boundary values are retrieved by solving the optimal problem which is constructed according to the best approximation between formal solutions and high-accuracy measurements in the interior of the domain. Finally, the assimilation problem is solved on substituting the retrieved boundary values into the Klein-Gordon equation. It is a type of inverse problem in mathematics. The advantage of this method lies in that it overcomes the inherent instability of the inverse problem of Fredholm integral equation and alleviates the error introduced by artificial boundary condition in data fusion using variational method in the past.

关键词： inverse problem Klein-Gordon Equation boundary condition data assimilation variational method

Climate-Induced Variability of Sea Level in Stockholm: Influence of Air Temperature and Atmospheric Circulation

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Advances in Atmospheric Sciences 2005年第5期22卷 655-664页

作者： Deliang CHEN Anders OMSTEDT Earth Sciences Centre Goteborg University Sweden Laboratory for Climate Studies/national Climate Center China Meteorological Administration Beijing 100081

This study is focused on climate-induced variation of sea level in Stockholm during 1873-1995. After the effect of the land uplift, is removed, the residual is characterized and related to large-scale temperature and atmospheric circulation. The residual shows an overall upward trend, although this result depends on the uplift rate used. However, the seasonal distribution of the trend is uneven. There are even two months （June and August） that show a negative trend. The significant trend in August may be linked to fresh water input that is controlled by precipitation. The influence of the atmospheric conditions on the sea level is mainly manifested through zonal winds, vorticity and temperature. While the wind is important in the period January-May, the vorticity plays a main role during June and December. A successful linear multiple-regression model linking the climatic variables （zonal winds, vorticity and mean air temperature during the previous two months） and the sea level is established for each month. An independent verification of the model shows that it has considerable skill in simulating the variability.

关键词： sea level Baltic sea atmospheric circulation temperature Stockholm

Impact of Atmospheric Transmittance and NLTE Correction on Simulation of High Spectral Infrared Atmospheric Sounder onboard FY-3E

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Journal of Meteorological Research 2024年第2期38卷 225-234页

作者： Chenggege FANG Peiming DONG Yang HAN Wanlin KAN Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological AdministrationNanjing University of Information Science&TechnologyNanjing 210044 Donghai Laboratory Zhoushan 316021 State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081 CMA Earth System Modeling and Prediction Centre China Meteorological Administration(CMA)Beijing 100081 Key Laboratory of transportation Meteorology of China Meteorological administration Nanjing Joint Institute for Atmospheric SciencesNanjing 210041

With the launch of the first civilian early-morning orbit satellite Fengyun-3E(FY-3E),higher demands are placed on the accuracy of radiative transfer simulations for hyperspectral infrared ***,several key issues are investigated in the ***,the accuracy of the fast atmospheric transmittance model implemented in the Advanced Research and Modeling System(ARMS)has been evaluated with both the line-by-line radiative transfer model(LBLRTM)and the actual satellite *** results indicate that the biases are generally less than 0.25 K when compared to the LBLRTM,while below 1.0 K for the majority of the channels when compared to the ***,during both comparisons,significant biases are observed in certain *** accuracy of Hyperspectral Infrared Atmospheric Sounder-II(HIRAS-II)onboard FY-3E is comparable to,and even superior to that of the Cross-track Infrared Sounder(CrIS)onboard ***,apodization is a crucial step in the processing of hyperspectral data in that the apodization function is utilized as the instrument channel spectral response function to produce the satellite channel-averaged *** further explore the difference between the apodized and unapodized simulations,Sinc function is adopted in the fast transmittance *** is found that the use of Sinc function can make the simulations fit the original satellite observations *** simulating with apodized observations,the use of Sinc function exhibits larger deviations compared to the Hamming ***,a correction module is applied to minimize the impact of Non-Local Thermodynamic Equilibrium(NLTE)in the shortwave infrared *** is verified that the implementation of the NLTE correction model leads to a significant reduction in the bias between the simulation and observation for this band.

关键词： high spectral infrared sounding atmospheric transmittance apodization Non-Local Thermodynamic Equilibrium Fengyun-3E(FY-3E)

Transcriptome-based identification and expression analysis of the glutathione S-transferase(GST)family in tree peony reveals a likely role in anthocyanin transport

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Horticultural Plant Journal 2022年第6期8卷 787-802页

作者： Lulu Han Hongzhu Zou Lin Zhou Yan Wang Research Institute of Forestry Key Laboratory of Tree Breeding and Cultivation of National Forestry and Grassland AdministrationChinese Academy of ForestryBeijing 100091China

For red-flowered cultivars of tree peony(Paeonia suffruticosa),anthocyanin content is a critical factor determining the different petal *** S-transferases(GSTs)are ubiquitous and multifunctional conjugating proteins that may be responsible for the transport of anthocyanin pigments from the cytoplasm to *** underlying function of the GST family in tree peony,however,remains *** this study,we systematically isolated and identified a total of 54 putative full-length Ps GST genes through a combination of bioinformatics approaches from transcriptome *** phylogenetic analyses revealed extensive differentiation in their coding sequences and divided them into 10 of the 14 known classes of plant *** phylogenetic relationships,evolutionary characteristics,protein domain,and motif organization were clearly conserved among the different phylogenetic *** results of the RNA-seq and quantitative real-time polymerase chain reaction experiments exhibited extensive variation in gene expression profiles among different developmental stages and ***,the phylogenetic relationships,expression profiles,protein interactions,weighted gene co-expression network analysis,and correlation analysis results suggested that PsGSTF3(Unigene 0064200)is a candidate participant in anthocyanin transport and the promotion of pigment accumulation,exhibiting a strong positive correlation with anthocyanin content among different tissues(r=0.908**)and an increasing rate of anthocyanin content during the flower developmental process(r=0.961*).These results furthered our understanding of the transport and accumulation functions of the GST family as well as the enhancement of tree peony breeding through molecular biology techniques.

关键词： GST Paeonia suffruticosa Functional prediction Expression analysis Anthocyanin transportation

Global woodland structure from local interactions:new nearest-neighbour functions for understanding the ontogenesis of global forest structure

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Forest Ecosystems 2020年第2期7卷 290-300页

作者： Arne Pommerening Hongxiang Wang Zhonghua Zhao Faculty of Forest Sciences Department of Forest Ecology and ManagementSwedish University of Agricultural Sciences SLUSkogsmarksgränd 17SE-90183 UmeåSweden College of Forestry Guangxi UniversityNanning 530004China Key Laboratory of Tree Breeding and Cultivation of national Forestry and Grassland administration Research Institute of ForestryChinese Academy of ForestryBox 1958Beijing 100091China.

Background:A number of hypotheses and theories,such as the Janzen-Connell hypothesis,have been proposed to explain the natural maintenance of biodiversity in tropical and temperate forest ***,to date the details of the processes behind this natural maintenance are still *** two new nearest-neighbour characteristics were proposed and in this paper we demonstrate how they can contribute to a better understanding of the ontogenesis of global forest structure from localised ***:We applied the new species and size segregation functions together with appropriate test procedures to four example woodland data sets from China at Daqingshan,Jiaohe,Jiulongshan and Xiaolongshan forest *** addition we quantified the morphology of the new characteristics and modelled a neighbourhood allometric coefficient linking the two ***:The results revealed quite different species segregation patterns with both conspecific and heterospecific *** found these to be generally matched by equivalent size segregation patterns of attraction of similar and different *** was straightforward to model the size segregation function from the knowledge of the species segregation function by estimating a neighbourhood allometric ***:The new characteristics have helped to quantify the extent and rate of decline of neighbourhood interactions in terms of spatial species and size *** the allometric neighbourhood coefficient the analysis highlighted once more how closely related species and size segregation are,thus supporting the minglingsize *** both a traditional and a restricted random-labelling test has provided a valuable tool for understanding the exact nature of species-mingling and size-inequality relationships.

关键词： Species segregation function Size segregation function Mingling-size hypothesis Neighbourhood allometric coefficient random labelling

Composite indicator for railway infrastructure management

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Journal of Modern transportation 2014年第4期22卷 214-224页

作者： Stephen M.Famurewa Christer Stenstrm Matthias Asplund Diego Galar Uday Kumar Division of Operation and Maintenance Engineering Lule University of Technology Lule Sweden Lule Railway Research Centre Lule Sweden Trafikverket (the swedish Transport administration) LuleSweden

The assessment and analysis of railway infra structure capacity is an essential task in railway infra structure management carried out to meet the required quality and capacity demand of railway transport. For sustainable and dependable infrastructure management, it is important to assess railway capacity limitation from the point of view of infrastructure performance. However, the existence of numerous performance indicators often leads to diffused information that is not in a format suitable to support decision making. In this paper, we demonstrated the use of fuzzy inference system for aggregating selected railway infrastructure performance indicators to relate maintenance function to capacity situation. The selected indicators consider the safety, comfort, punctuality and reliability aspects of railway infrastructure performance. The resulting composite indicator gives a reliable quanti fication of the health condition or integrity of railway lines. A case study of the assessment of overall infrastructure performance which is an indication of capacity limitation is presented using indicator data between 2010 and 2012 for five lines on the network of Trafikverket （swedish Trans port administration）. The results are presented using cus tomised performance dashboard for enhanced visualisation,quick understanding and relevant comparison structure conditions for strategic management. This gives additional information on capacity status and limitation from maintenance management perspective.

关键词： Composite indicator Infrastructure capacityFuzzy logic Performance dashboard Strategic decisionsLine integrity