Analysis of Development Causes and Reasons on Logistics Public Information Platform in Road Freight Market of China

This paper based on the analysis and comparison of two major changes of our road freight market affected by reforming andopening-up, and discusses that the origin, course and motivation of the Logistics public information platform（LPIP）. Then it Points that theessential reason is the asymmetry of information exchange, course of its development is in order to meet the different needs of different stagesof the market continuously adjusted to the function of a process of development, but also development of the market to a specifi c stage of theinevitable demand.

Effect of microbial mediated iron plaque reduction on arsenic mobility in paddy soil

The potential of microbial mediated iron plaque reduction, and associated arsenic （As） mobility were examined by iron reducing bacteria enriched from As contaminated paddy soil. To our knowledge, this is the first time to report the impact of microbial iron plaque reduction on As mobility. Iron reduction occurred during the inoculation of iron reducing enrichment culture in the treatments with iron plaque and ferrihydrite as the electron acceptors, respectively. The Fe（II） concentration with the treatment of anthraquinone-2, 6-disulfonic acid （AQDS） and iron reducing bacteria increased much faster than the control. Arsenic released from iron plaque with the iron reduction, and a significant correlation between Fe（II） and total As in culture was observed. However, compared with control, the increasing rate of As was inhibited by iron reducing bacteria especially in the presence of AQDS. In addition, the concentrations of As（III） and As（V） in abiotic treatments were higher than those in the biotic treatments at day 30. These results indicated that both microbial and chemical reductions of iron plaque caused As release from iron plaque to aqueous phase, however, microbial iron reduction induced the formation of more crystalline iron minerals, leading to As sequestration. In addition, the presence of AQDS in solution can accelerate the iron reduction, the As release from iron plaque and subsequently the As retention in the crystalline iron mineral. Thus, our results suggested that it is possible to remediate As contaminated soils by utilizing iron reducing bacteria and AQDS.

Evaluation of the stability of vegetated slopes according to layout and temporal changes

Vegetation in slopes can effectively improve slope stability.However,it is difficult to estimate the effects of vegetation on slope stability because of variations in plant species and environmental conditions.Moreover,influences of plant growth on slope stability change with time,resulting in changes in the safety factor.This study was conducted to evaluate the stability of vegetated slopes with time and investigate the effects of different layouts of plant species on slope stability.Here,we used a plant growth model and slope stability analysis to build an evaluation model.To accomplish this,one species of tree,shrub and grass was chosen to set six layout patterns.A slope with no vegetation served as a control.The safety factors of the seven slopes were then calculated using the developed evaluation model and differences in the safety factors of slopes were compared and discussed.The slope vegetated with Platycladus orientalis reached the most stable state at the age of 60 years.Shrub slope(Vitex negundo)had the maximum safety factor after 20 years.Overall,the safety factor of vegetated slopes increased from 12.1%to 49.6% compared to the slope with no vegetation.When wind force was considered,the safety factor value of the slope changed from 3.5%to 43.5%.Vegetation mixtures of trees and grasses resulted in the best slope stability.Planting grasses on slopes can improve slope stability of trees to a greater degree than that of slopes with shrubs in the early stage of growth.

Analytical modeling of complex contact behavior between rock mass and lining structure

Based on the nondestructive test data of operating railway tunnels in China, this paper summarizes the basic characteristics of the complex contact behavior between the rock mass and lining structure. The contact modes are classified into dense contact, local non-contact, and loose contact. Subsequently, the corresponding mechanical model for each contact mode is developed according to its mechanical characteristics using the complex variable method. In the proposed mechanical model, a special algorithm is introduced to detect whether the local non-contact zone is re-contacted. Besides, a novel conformal mapping method is also proposed to accurately calculate the mechanical response of the concrete lining. Finally, the accuracy of the proposed method is verified by comparing it with the finite element method(FEM). Several parameter investigations are conducted to analyze the effects of different contact modes on the rock-lining interaction. The results show that:(i) the height of the local noncontact area does not have a significant effect on the contact stress distribution if no re-contact occurs;(ii) backfill grouting can reduce the local stress concentration caused by poor contact modes;and(iii) reducing the friction coefficient of the interface can lead to a more uniform distribution of internal forces in the concrete lining.

Analysis of effect factors-based stochastic network planning model

Looking at all the indeterminate factors as a whole and regarding activity durations as independent random variables, the traditional stochastic network planning models ignore the inevitable relationship and dependence among activity durations when more than one activity is possibly affected by the same indeterminate factors. On this basis of analysis of indeterminate effect factors of durations, the effect factors-based stochastic network planning （EFBSNP） model is proposed, which emphasizes on the effects of not only logistic and organizational relationships, but also the dependent relationships, due to indeterminate factors among activity durations on the project period. By virtue of indeterminate factor analysis the model extracts and describes the quantitatively indeterminate effect factors, and then takes into account the indeterminate factors effect schedule by using the Monte Carlo simulation technique. The method is flexible enough to deal with effect factors and is coincident with practice. A software has been developed to simplify the model-based calculation, in VisualStudio.NET language. Finally, a case study is included to demonstrate the applicability of the proposed model and comparison is made with some advantages over the existing models.

A Review on the Classification and Grading Criteria of Road Transport Natural Disasters

This review summarizes and analyzes the basic information of various types of road transport natural disaster emergencies,refers to various types of road transport emergency plans,and combines the actual needs of road transport emergency rescue with national emergency related laws.It also proposes the classification criteria and grading standard for the emergencies of road transport natural disasters based on the classification and grading standard of the regulations,which provide a basis to take reasonable and effective disposal measures in the emergency response of road transport emergencies under natural disaster conditions.

Residual Capacity of Friction⁃Type High⁃Strength Bolted T⁃stub Connection with Nut Corrosion Damage

Corrosion is a primary cause of the slippage of friction⁃type high⁃strength bolted(FHSB)T⁃stub connections.This paper attempts to quantify the residual capacity of FHSB T⁃stub connections with corroded nuts.Firstly,corrosion simulation tests were conducted on 48 manually cut nuts to find out the relationship between the damage degree of nut section and the residual clamping force(RCF)of bolt.Then,static load tests were carried out on 24 FHSB T⁃stub connections with nuts of different degrees of damage to obtain the failure modes.By finite⁃element(FE)models,a comparative analysis was performed on the initial friction load(IFL)and ultimate strength(US)of each connection with corroded nuts.Finally,the parameters of 96 FE models for FHSB T⁃stub connections were analyzed and used to derive the calculation formulas for the degree of damage for each nut and the IFL and US of each connection.The results show that the RCF decay of a bolt is a quadratic function of the equivalent radius loss ratio and the shear failure after nut corrosion;the IFL of each connection had a clear linear correlation with the RCF of the corresponding bolts,and the correlation depends on the applied load and static friction on connecting plate interface induced by the clamping force;the static friction had little impact on the US of the connection;the proposed IFL and US formulas can effectively derive the residual anti⁃slip capacity of FHSB T⁃stub connections from the degree of damage of the corroded nut section.The research results provide a scientific basis for the replacement and maintenance of corroded bolts of FHSB T⁃stub connections.

Wildlife Crossing Zones along the Ring Changbai Mountain Scenic Highway, China

The 84-km long Changbai Mountain scenic Ring highway encircles and bisects the nature reserve. With the expected increasing traffic flow, increased wildlife vehicle collisions and barrier effects are likely. In order to identify wildlife crossing zones and future protective measurement, the authors carried out 10 wildlife highway crossing surveys during the winter in 2008-2009. For each 5-kin section, the authors recorded highway crossings of all small/mid-sized and large mammals and one large protected bird species, the hazel grouse （Bonasa bonasia） and noted snow depth and the dominant vegetation type. The authors detected 12 mammal species and one avifauna species crossing the highway 502 times. The smallest of mammal was the Eurasian red squirrel （Sciurus vulgaris）. Large mammals detected included the wild boar （Sus scrofe） （64） and brown bear （Ursus arctos） （1）. The average number of wildlife crossings per 5 km was 29.5. It was found that species richness and crossing frequency was higher in sections with broad leaf forest compared to sections with white birch secondary forest significantly. The authors suggested that disturbance of broad leaf forest be minimized during construction and strict protection be established for broad leaf forests around Changbai Mountain National Nature Reserve.

Investigation of Occupational Hazards in Transport Wharf of Liquid Chemicals

Occupational health management of liquid chemical transport wharf is still in its infancy,to grasp the occupational health status of employees in the industry and improve the occupational health management level of employees,taking the liquid chemical transport wharf of an enterprise as the investigation object,according to the relevant domestic occupations.Hygiene standards,using the combination of on-site occupational hygiene survey and workplace occupational hazard factors detection,identify the occupational hazard factors of the wharf and detect the degree of hazard.The survey results show that the overall occupational health of the wharf is basically good,but the noise index is slightly exceeded.It is suggested to further improve the occupational health management level of the wharf by improving the protection technology and strengthening the administrative management.

Do rural highways narrow Chinese farmers'income gap among provinces?

To achieve complete poverty alleviation,the improvement of infrastructure and living conditions is fundamental.Promoting the flow of factors through infrastructure investment,thereby reducing the income gap among residents,has become an important focus of poverty alleviation.Because of the high amount of investment in transportation infrastructure,greater attention has been paid to the income distribution effect it brings,but few studies have analysed the effect of rural highways on the income gap of farmers.Based on the panel data pertaining to 30 provinces in China from 1993 to 2013,this paper uses a fixed-effect model to test the impact of rural highways supply on the income gap of farmers.The empirical results show that:(1)The effect of Chinese rural highways on the farmers'income gap among provinces is"U-shaped".(2)Chinese national and provincial trunk highways are helpful in narrowing the farmers'income gap among provinces.(3)The level of education,household productive fixed assets investment,level of urbanization,and level of regional economic development have multiple effects on the farmers'income gap among provinces.Then,based on the empirical analysis,the paper analyzes the mechanism of rural highways affecting the income gap of farmers from a theoretical perspective and focuses on the causes of the"U-shaped"relationship between rural highways supply and farmers'income gap.

青藏公路边坡防护试验研究(英文)

The results brought out in the trials of slope protection along Qinghai-Tibet Highway are presented in this paper. The trials were carried out simultaneously at 5 sites in Qinghai-Tibet Plateau from 2000 to 2002. Altitudes at the experimental sites range between （4 240） m and （5 040） m. 4 sites are in permafrost area, and 1 site is in seasonally frozen ground. According to the trials of slope protection, vegetation is preferred to protect slopes along Qinghai-Tibet Highway. Road-GoodR, a chemical stabilizer, is proved as a good material for slope protection, and soil engineering system, combined with vegetative component and grade stabilization structures is proved as the best slope protection measure in these areas. The results showed that high-altitude areas at an altitude lower than （5 040） m, annual average temperatures higher than （-5.6） ℃ and annual rainfall more than 262\^2 mm, slopes can be protected using vegetative components.\;Trials for plant species selection proved that cold resistant grasses, Elymus nutans and Elymus sibiricus can be used for vegetation recovery along Qinghai-Tibet Highway. The results demonstrated that high-altitude areas at an altitude lower than （5 040） m, annual average temperatures higher than （-5.6） ℃ and annual rainfall more than 262\^2 mm, could be replanted. Hydroseeding proved to be a good planting technique, and mulch materials benefited vegetation recovery in such area.\;The experiment also proved that planting could improve slope stability, protect the ecological environment, and improve the roadside landscape.

Research on Construction of an Accessible Environment in the Context of Building a Country with a Strong Transportation Network

Transportation is a basic service industry concerned with people’s livelihood and well-being. China has unveiled guidelines on improving China’s strength in transportation. By 2035, an accessible travel service system should basically be built, according to the guidelines jointly released by the Communist Party of China Central Committee and the State Council. It is of great practical significance to accelerate the construction of an accessible transportation environment in the new era, which can improve the equalization of public services and promote the safe, convenient, and comfortable travel of the disabled and the elderly. In line with the development status of transportation in China, and through an analysis on the requirements for building a country with a strong transportation network, this paper proposes the framework and content for the establishment of an accessible transportation system in China.

Estimating optimal substitution scale of urban gasoline taxis by electric taxis in the era of green energy:a case study of Zhengzhou City

Electric Taxis(ETs)are the most favored alternatives to Gasoline Taxis(GTs)in cities that aim to reduce environmental pollution.How to develop a reasonable scale on which GTs are substituted by ETs remains a challenge to governments due to the dynamics and complexity of the taxi system.To address this challenge,this paper develops a discrete-event-based simulation framework to simulate participants in the system and estimate the results under different substitution scales,which are helpful to understanding the status changing law of entities under different substitution scales,such as the operating indices of ETs,the unsatisfied travel requirements of passengers,and the usage state of charging facilities.The framework abstracts the behavioral process of ETs into three elements,namely,entity,behavior,and event.The entities are constructed from the information derived from the trajectory data.The behaviors are defined by rules following behavioral logic under anxiety psychology,which is caused by the limited range of ETs.The events are triggered based on rules from reality.With the help of this framework,a multi-objective optimization model is developed to obtain the optimal substitution scale of GTs in the case study area of Zhengzhou City.Overall,the approach could provide a practical tool to address this challenge,which could support further studies of the effect of ETs on urban taxis.

Rill erosion and controlling factors on highway side-slopes in the permafrost region

Soil erosion on highway side-slope has been recognized as a cause of environmental damage and a potential threat to road embankments in the high-altitude permafrost regions.To assess the risk to roads and to protect them effectively,it is crucial to clarify the mechanisms governing roadside erosion.However,the cold climate and extremely vulnerable environment under permafrost conditions may result in a unique process of roadside erosion,which differs from the results of current studies conducted at lower altitudes.In this study,a field survey was conducted to investigate side-slope rill erosion along the permafrost section of a highway on the Qinghai‒Tibet Plateau of China.Variations in erosion rates have been revealed,and intense erosion risks(with an average erosion rate of 13.05 kg/m^(2)/a)have been identified on the northern side of the Tanggula Mountains.In the case of individual rills,the detailed rill morphology data indicate that the rill heads are generally close to the slope top and that erosion predominantly occurs in the upper parts of highway slopes,as they are affected by road surface runoff.In the road segment scale,the Pearson correlation and principal component analysis results revealed that the protective effect of vegetation,which was influenced by precipitation,was greater than the erosive effect of precipitation on roadside erosion.A random forest model was then adopted to quantify the importance of influencing factors,and the slope gradient was identified as the most significant factor,with a value of 0.474.Accordingly,the integrated slope and slope length index(L0.5S2)proved to be a reliable predictor,and a comprehensive model was built for highway side-slope rill erosion prediction(model efficiency=0.802).These results could be helpful for highway side-slope conservation and ecological risk prediction in alpine permafrost areas.

Simultaneous Estimation of Multiple Conditional Regression Quantiles

In this article, we put forward a new approach to estimate multiple conditional regression quantiles simultaneously. Unlike the double summation method in most of the literatures, our proposed model allows continuous variety for the quantile level over(0,1). As a result, all the quantile curves can be obtained via a 2-dimensional surface simultaneously. Most importantly, the proposed minimizing criterion can be readily transformed to a linear programming problem. We use tensor product bi-linear quantile smoothing B-splines tofit it. The asymptotic property of the estimator is derived and a real data set is analyzed to demonstrate the proposed method.

Laplacian-based 3D mesh simplification with feature preservation

We propose a novel Laplacian-based algorithm that simplifies triangle surface meshes and can provide different preservation ratios of geometric features.Our efficient and fast algorithm uses a 3D mesh model as input and initially detects geometric features by using a Laplacian-based shape descriptor(L-descriptor).The algorithm further performs an optimized clustering approach that combines a Laplacian operator with K-means clustering algorithm to perform vertex classification.Moreover,we introduce a Laplacian weighted cost function based on L-descriptor to perform feature weighting and error statistics comparison,which are further used to change the deletion order of the model elements and preserve the saliency features.Our algorithm can provide different preservation ratios of geometric features and may be extended to handle arbitrary mesh topologies.Our experiments on a variety of 3D surface meshes demonstrate the advantages of our algorithm in terms of improving accuracy and applicability,and preserving saliency geometric features.

Capturing driving behavior Heterogeneity based on trajectory data

Driving behavior is heterogeneous for various drivers due to the different influencing factors as reaction time,gender,driving years and so on.Some existing works tried to reproduce some of the complex characteristics of real traffic flow by taking into account the heterogeneous driving behavior,and the drivers are generally divided into two classes(including aggressive drivers and careful drivers)or three classes(including aggressive drivers,normal drivers and careful drivers).Nevertheless,the classification approaches have not been verified,and the rationality of the classifications has not been confirmed as well.In this study,the trajectory data of drivers is extracted from the NGSIM datasets.By combining the K-Means method and Silhouette measure index,the drivers are classified into four clusters(named as clusters A,B,C and D,respectively)in accordance with the acceleration and time headway.The two-dimensional approach is applied to analyze the characteristics of different clusters.Here,one dimension consists of“Cautious”and“Aggressive”behaviors in terms of velocity and acceleration,and the other dimension consists of“Sensitive”and“Insensitive”behaviors in terms of reaction time.Finally,the fuel consumption and emissions for different clusters are calculated by using the VT-Micro model.A surprising result indicates that overly“cautious”and“sensitive”behaviors may result in more fuel consumption and emissions.Therefore,it is necessary to find the balance between the driving characteristics.

Longitudinal control for person-following robots

Purpose–This paper aims to address the longitudinal control problem for person-following robots(PFRs)for the implementation of this technology.Design/methodology/approach–Nine representative car-following models are analyzed from PFRs application and the linear model and optimal velocity model/full velocity difference model are qualified and selected in the PFR control.Findings–A lab PFR with the bar-laser-perception device is developed and tested in the field,and the results indicate that the proposed models perform well in normal person-following scenarios.Originality/value–This study fills a gap in the research on PRFs longitudinal control and provides a useful and practical reference on PFRs longitudinal control for the related research.

The General Control Method for Highway Network Planning

Reviewing the developing process of highway network planning, this paper comprehensively introduced the main ideas, the main contents and working steps of the General control method. It also pointed out the prblems remaining for settlement.