Accessibility for High Asia： Comparative Perspectives on Northern Pakistan＇s Traffic Infrastructure and Linkages with Its Neighbours in the Hindukush-Karakoram- Himalaya

Starting with a discussion of development concepts which were applied in practice and which followed the developmentalist paradigm the expansion of traffic infrastructure in colonial and post-colonial periods is presented for the High Asian mountain rim. Selective railways and roads are the major feature of this development, which aimed first on serving the convenience of hill station visitors and followed strategic considerations later on. This bias between regional planning and implementation remains a characteristic feature. At the same time traffic infrastructure without asphalt roads is important for the mountain areas, thus breaking up the strong correlation between development and asphalt roads.     

Gradient effect of road transportation on economic development in different geomorphic regions

The economic benefits of transport infrastructure investment have been widely accepted. However, the varying influence of road transport development across vertical space has rarely been discussed. Taking Sichuan province in China as case study area where the landform is diverse and complex, administrative counties were categorized into 4 main types: plain counties, hill counties, mountain counties, and plateau counties. Using statistical data during 2006-2014, the performance of economic development and transport construction level in the four types of counties are discussed. Subsequently, the heterogeneous effect of each grade road on economy was calculated by local regression model (GWR). The results indicate that plain counties largely surpassed the other geomorphic counties in economic development level, while the gradient gap among them was on the decline. Similarly, distribution of transport infrastructure presented a decreasing trend from the low plain counties to high plateau counties. Regional imbalances were mainly reflected in the County road and Village road. Regarding the changes of regional gaps, National & Provincial roads and County roads were constantly expanding, whereas the disparity of Village road was slowly narrowing over time. Particularly noteworthy was the non-stationary economic influence of traffic factors across vertical gradients. On average, National & Provincial roads generated higher benefits in the high elevation regions than the lowlands. In contrast, County road and Village road were found to be more effective in promoting economic development in plains. With regard to local estimates of traffic factors, coefficients in mountain counties exhibited larger fluctuation ranges than other geomorphic units. The conclusions provide a basis for government decisionmaking in a more reasonable construction arrangement of road facilities and sustainable economic development.     

基于道路结构特征识别的城市交通状态空间自相关分析

 城市道路交通状态具有空间自相关特征。路段交通状态的变化会很快影响到邻近路段,导致一定空间范围内路段的交通状态发生改变。揭示城市交通状态的空间自相关特征,对交通规划、交通控制与诱导具有重要意义。然而,受到城市路网空间结构和道路拓扑特征的影响,城市道路交通状态的空间自相关并非各向同性,也并非均匀地向上下游扩散,而是有选择性地集中在部分邻近路段上。因此,仅考虑路段地理空间下的上下游邻近性,难以全面度量路段间交通状态的相互影响,识别出交通状态空间相关性强的道路集合。本文借鉴复杂网络分析方法,定量化分析了城市路网的模块化与层次性特征,利用城市路段在空间上的聚集特征和路段在网络中拓扑角色的差异,提出了一种新的交通状态自相关路段邻近性判别规则,即空间邻近且拓扑等价规则,以此规则实现交通状态空间相关路段聚类过程,更好地揭示城市路段之间的交通状态空间相关性。     

Degradation of a protected mountain area by tourist traffic: case study of the Tatra National Park,Poland

Mountain protected areas are characterized by high biodiversity, which makes it a great challenge for managers to maintain a balance between their use and the stability of natural ecosystems. Maintaining that balance is particularly difficult in areas with high tourism pressure. The expected volume of tourist traffic should be considered at the planning stage of the tourist infrastructure development process. Insufficient capacity of tourist infrastructure can lead to environmental degradation, which is hard, or at times impossible, to repair. In our research, we identified patterns of tourist footpath and road functioning in an environmentally protected area with high volumes of tourist traffic. Data from geomorphologic mapping was analyzed in order to identify tourist footpath and road structures in the Tatra National Park(TNP). Fieldwork was conducted in several stages between 1995 and 2019. Orthophotomaps from the years 1977, 2009, 2017 and 2019 were used to identify and compare degraded zones along selected tourist footpaths. Degraded zones were defined as areas surrounding a footpath or tourist road with a mean width larger than or equal to 10 meters, with heavily damaged or completely removed vegetation and exposed, weathered cover, where geomorphic processes that would not take place under normal conditions are readily observable. The examined tourist footpaths and roads vary in terms of their morphometric parameters. Research has shown important differences between mean and maximum footpath width as well as maximum incision depth for the forest zone versus the subalpine and alpine zones. A lack of differences in these parameters was noted between the alpine and subalpine zones. Research has shown that an increase in the surface area of degraded zones found adjacent to tourist footpaths occurred in all the studied geo-ecological zones in the study period. However, the largest increase occurred atop wide ridgelines found in the alpine zone. Degraded zones may be an indication of exceeding the tourist carrying capacity of a mountain tourist area. Mass tourism in TNP contributes to the formation of degraded zones adjacent to footpaths, whose continuous evolution may lead to irreversible changes in local relief.     

基于拓扑与形态特征的城市道路交通状态空间自相关分析

城市道路交通状态具有空间自相关特征。某一道路交通状态的变化会对其周边道路产生影响,故把握道路交通状态的空间自相关性是提高交通规划、交通预测水平的基础。然而,城市道路交通状态又具有空间异质性,即道路交通状态的影响扩散并非各向同性,其使得道路交通状态空间自相关性的度量更为复杂,因此仅从地理空间下道路之间的邻近关系出发进行分析有失偏颇。同时,城市道路具有拓扑结构特征和几何形态特征,二者对于交通状态自相关性的影响和制约,却未引起足够重视。本文从城市道路的拓扑结构特征和几何形态特征出发,提出了一种新的交通状态空间自相关路段识别规则,即基于交通状态变化的路段空间识别规则,通过拓扑社区发现方法刻画路段在空间上的聚集特征,同时,基于Stroke跟踪的几何形态概化来描述道路交通状态变化影响的空间异质性。结果表明,利用本文提出的识别规则产生的交通状态自相关路段集合,较仅考虑地理空间邻近或拓扑结构的识别规则更为合理,更好地揭示了城市道路交通状态的空间自相关特征。     

基于自发地理信息的“一带一路”区域陆路交通状况分析

路网密度的研究是实施“一带一路”愿景之互联互通倡议的基础工作。“一带一路”顺应了世界经济全球化、一体化、多极化、信息化的趋势,牵连着蓬勃发展的亚太和发达的欧洲经济圈,带动中间国家的经济发展。在新形势下,如何通过交通基础设施建设推进丝绸之路经济带沿线区域间的互联互通、促进区域合作和经济发展,具有重要的现实意义。本文利用自发地理信息数据——OpenStreetMap（OSM）道路网数据,运用地理信息系统（GIS）空间分析技术,探究了“一带一路”陆路经济带辐射区域亚欧大陆的路网络密度和通行能力的空间分布格局,并分析了六大经济走廊节点城市的公路可达性空间格局。结果表明：“一带一路”陆路经济带的交通基础设施的发展存在着不平衡现象;路网密度和通行能力均呈现沿海高内陆低的空间格局;中亚、西亚地区和中南半岛地区成为道路水平落后带,限制了丝绸之路经济带资源整合与贸易畅通,建议在建设新跨国公路铁路同时,对原有老旧道路进行加宽加固等升级改造;全区域道路等级级配不合理;节点城市可达性具有明显的分异状况,六大经济走廊中83%的区域可达性在10 h以内。研究产出亚欧大陆1 km分辨率路网密度和通行能力数据集,发现了“一带一路”陆路经济带道路水平的薄弱区域,为“一带一路”陆路经济带的交通基础设施建设以及进一步的道路网研究提供了基础数据。     

城市交通干线对盐城城市发展影响的空间分析

本文以江苏省盐城市为例,通过1990、2000、2010年3期盐城市域遥感影像解译,获取盐城市土地利用变化数据,并采用GIS空间分析技术,评估城市交通干线对城市发展的影响。同时,结合Model Builder建模技术,综合运用缓冲区分析、叠加分析、统计分析等方法进行快速、一站式土地利用变化分析。研究结果表明:(1)以道路沿线5km缓冲区及道路出口10km缓冲区研究范围为最佳;(2)盐城市城市交通干线沿线5km范围内随着相应交通基础设施的建设变化非常剧烈,2000年后,高等级公路、高速公路和铁路改建及新建导致沿线土地利用变化发展迅速,特别是204国道沿线和沈海高速沿线变化最为迅速;(3)盐城市城市交通干线沿线重要交通出口10km范围内的变化也极大,新长铁路盐城站出口周边变化最为迅速。     

沂蒙山区南龙口岩溶地面塌陷形成机制探讨

沂蒙山区南龙口隐伏灰岩分布区,上覆第四系砂砾石层、砂质黏土等,受地下水集中开采、降水等诱发因素的影响,近年来多次发生地面塌陷,导致交通干线、民房及村中道路受损,造成一定的经济损失,对当地村民的生命安全及重要交通干线构成威胁。该文初步分析研究了岩溶地面塌陷的特征、形成条件及影响因素,提出了防灾减灾措施。     

Shifting dynamics of nature,society and agriculture in the Hindu Kush Himalayas: Perspectives for future mountain development

Current approaches for sustainable mountain development have several persisting warning signals. Economic globalization, profitoriented market development, and infrastructure development have significantly altered traditional nature-society interactions, increased environmental pressures, and challenged agricultural sustainability in the mountains. Some of the effects of globalization could also be beneficial. Social differentiation and disintegration of mountain communities' have weakened their collective stakes on natural resources resulting in decline in initiatives such as community forestry, collective water management, domestication of rapidly disappearing herbal species, and balancing of economic and ecological concerns. Population growth, food insecurity, unemployment, and increasing economic gaps between rich and poor have led to out-migration of youth. Sustained action promoting ownership of new initiatives for rehabilitating degraded mountain landscapes through macro-level global/national initiatives, mountain specific planning and development efforts is severely lacking in many areas on the Hindu Kush Himalayan region. Therefore, there is an urgent need for widening the scope of efforts directed to help mountain areas and communities, and a future thinking approach to enhance the sustainability of mountain areas as they are a valuable natural resource for humankind. This paper discusses the issues, opportunities, and provides suggestions for the future of mountain development.     

Spatiotemporal patterns of road network and road development priority in three parallel rivers region in Yunnan, China: An evaluation based on modified kernel distance estimate

Road network is a critical component of public infrastructure,and the supporting system of social and economic development.Based on a modified kernel density estimate(KDE)algorithm,this study evaluated the road service capacity provided by a road network composed of multi-level roads(i.e.national,provincial,county and rural roads),by taking account of the differences of effect extent and intensity for roads of different levels.Summarized at town scale,the population burden and the annual rural economic income of unit road service capacity were used as the surrogates of social and economic demands for road service.This method was applied to the road network of the Three Parallel River Region,the northwestern Yunnan Province,China to evaluate the development of road network in this region.In results,the total road length of this region in 2005 was 3.70×104km,and the length ratio between national,provincial,county and rural roads was 1∶2∶8∶47.From 1989 to 2005,the regional road service capacity increased by 13.1%,of which the contributions from the national,provincial,county and rural roads were 11.1%,19.4%,22.6%,and 67.8%,respectively,revealing the effect of′All Village Accessible′policy of road development in the mountainous regions in the last decade.The spatial patterns of population burden and economic requirement of unit road service suggested that the areas farther away from the national and provincial roads have higher road development priority(RDP).Based on the modified KDE model and the framework of RDP evaluation,this study provided a useful approach for developing an optimal plan of road development at regional scale.     

Evolution and development of Guangzhou-Hong Kong corridor

1IN T R O D U C T IO NThe concept ofthecorridorhas a long historyintheur-ban and regionalresearch.Because of itsgreatimpor-tanceand impacts,researchon corridors has receivedgrowing attentionof geographers.Studieshave rangedfrom the theoreticaulnderpinning…     

Risk-based evaluation on geological environment carrying capacity of mountain city - A case study in Suide County,Shaanxi Province,China

With the rapid development and expansion of the cities in China, the carrying capacity of resource and environment has become a huge concern for local governments. From the perspective of geological environment, geological disasters are the main restraining factor of the development in mountain cities. This study was conducted in Suide County of Shaanxi Province with a risk-based approach as followed: a hazard analysis on geological disasters based on a slope geological survey at a scale of 1:10,000; a consequence analysis based on unmanned aerial vehicle (UAV) aerial survey data; integrating the results of hazard analysis and consequence analysis, a risk zonation and analysis of geological disasters in urban areas were completed considering urban planning, land use planning and the safety of infrastructure and major engineering. Subsequently, taking the acceptable levels of human life and property risks incurred by landslides as the criteria of the evaluation of geological environment carrying capacity, a comprehensive assessment of current and future urban carrying capacity was conducted based on the results of the risk analyses. Accordingly, the prior development zone, the restricted development zone and the prohibited zone were delineated, with corresponding suggestions for future urban development. The technological and methodological system used in the study can be applied to geological environment carrying capacity evaluation of other important mountain cities, which can provide scientific basis for the optimization of land and space.     

基于Anchor-free的交通标志检测

交通标志检测是自动驾驶中的重要研究方向,实时准确地从街景图像中检测交通标志对实现自动驾驶及智慧城市的发展具有重要意义。传统的算法基于颜色、形状特征进行检测,只能提取特定种类的交通标志,算法无法同时检测不同类型的交通标志。基于图像特征+机器学习分类器的算法需要人工设计特征,算法速度较慢。主流的基于深度学习的方法多基于先验框,在网络设计上引入了额外的超参数,且在训练过程中产生过量的冗余边界框,容易造成正负样本不平衡。本文受Anchor-free思想的启发,引用YOLO检测器直接回归物体边界框的思路,提出一种基于Anchor-free的实时交通标志检测网络AF-TSD（Anchor-free Traffic Sign Detection）。AF-TSD摒弃了先验框的设计,并引入自适应采样位置可变卷积与注意力机制,大大提高网络的特征表达能力。本文开展大量对比实验,实验结果表明本文提出的AF-TSD交通标志检测网络速度接近主流算法,但精度优于主流算法,在德国GTSDB交通标志检测数据集上取得了96.80%的精度,检测速度平均单张图片32 ms,达到实时检测的要求。     

基于交通网络的乡村中小学优化布局

合理规划中小学布局是优化教育资源配置、提高办学效益以及实现教育均衡发展的重要途径。本研究针对中国乡村建设的需要和中国多山的地理环境,考虑山地环境对乡村中小学选址的影响,构建多山环境下乡村中小学的区位模型,运用地理信息科学方法,以Visual Studio. Net 2010为开发平台,使用C#语言和ArcGIS Engine 10.0组件库,同时结合MATLAB编程,开发出基于交通网络的乡村中小学区位优化系统。最后将系统应用于贵州省某镇的小学布局优化中,分别在只考虑已有道路、假设道路可升级、假设道路可新建或升级3种情景下,通过改进的模拟退火算法,确定新建学校的最佳位置,以及新道路的修建和原有道路的升级情况,从而得到不同情景下各居民点学生的上学耗时。结果表明,交通网络对乡村中小学布局优化具有重要影响,改善交通网络条件能够有效提高学生的就学效率上学速度。     

面向对象的高空间分辨率遥感影像道路信息的提取

遥感影像的道路信息提取是构建及更新地理空间数据库的一个重要组成部分。针对高空间分辨率遥感影像丰富的地物细节信息和突出的结构、纹理信息的特点,采用一种面向对象技术,实现了高空间分辨率影像道路信息提取。首先,利用面向对象的影像分割技术得到道路均值对象,然后挖掘高空间分辨率遥感影像中描述道路的光谱特征、几何特征及纹理特征,构建道路对象的知识库,实现了城郊重要道路信息的提取。与最大似然法相比,提取结果充分利用道路形状和纹理信息,能克服光谱特征的噪声现象,提取道路准确率高,为高空间分辨率遥感影像道路信息提取提供了一种新的途径。     

Relationship Between Urban Road Traffic Characteristics and Road Grade Based on a Time Series Clustering Model: A Case Study in Nanjing,China

With the increasing number of vehicles in large- and medium-sized cities challenges in urban traffic management, control, and road planning are being faced. Taxi GPS trajectory data is a novel data source that can be used to study the potential dynamic traffic characteristics of urban roads, and thus identify locations that show a notable lack of road planning. Considering that road traffic characteristics on their own are insufficient for a comprehensive understanding of urban traffic, we develop a road traffic characteristic time series clustering model to analyze the relationship between urban road traffic characteristics and road grade based on existing taxi trajectory data. We select the main urban area of Nanjing as our study area and use the taxi trajectory data of a single month for evaluating our method. The experiments show that the clustering model exhibit good performance and can be successfully used for road traffic characteristic classification. Moreover, we analyze the correlation between traffic characteristics and road grade to identify road segments with planning designs that do not match the actual traffic demands.     

Study on the performance of the micropile-mechanically stabilized earth wall

The Micropile-Mechanically Stabilized Earth (MSE) wall, specially designed for mountain roads, is proposed to improve the MSE wall local stability, global stability and impact resistance of roadside barriers. Model tests and the corresponding numerical modeling were conducted to validate the serviceability of the Micropile-MSE wall and the reliability of the numerical method. Then, a parametric study of the stress and deformation of Micropile-MSE wall based on the backfill strength and interfacial friction angle between backfill and backslope is conducted to evaluate its performance. The test results indicate that the surcharge-induced horizontal earth pressure, base pressure and lateral displacement of the wall panel of Micropile-MSE wall decrease. The corresponding numerical results are nearly equal to the measured values. The basic failure mode of MSE wall in steep terrain is the sliding of backfill along the backslope, while A-frame style micropiles are capable of preventing the sliding trend. The maximum resultant displacement can be decreased by 6.25% to 46.9% based on different interfacial friction angles, and the displacement can be reduced by 6% ~ 56.1% based on different backfill strengths. Furthermore, the reduction increases when the interfacial friction angle and internal friction angle of backfill decrease. In addition, the lateral displacement of wall panel, the deformation of backfill decrease and the tension strain of geogrid obviously, which guarantees the MSE wall functions and provides good conditions for mountain roads.     

面向山地徒步应急救援路径规划的改进蚁群算法研究

当消防事故发生在无明显道路或道路稀疏的野外复杂山区时,如何在复杂山地环境中规划安全、快速通过的路线至关重要。针对蚁群算法在复杂山地路径规划中容易陷入局部最优以及搜索时间较长的问题,本文提出一种适用于细粒度野外山地环境的徒步应急救援路径规划算法。本文首先根据已有文献分析地表信息与人类运动速度之间的关系,综合地表灌木盖度与地形坡度因素设计寻优算法的目标函数和启发函数;接着采用定向范围视野的蚂蚁搜索方式,决定蚁群算法寻优过程中每一步的网格选择;最后采用拉普拉斯分布调整初始信息素、添加隔离信息素、融合遗传算子与分组更新常规信息素的方法改进蚁群算法。将算法应用到400×400、1000×1000、5000×5000、10 000×10 000网格数的野外山地环境进行实验对比,实验结果表明,采用定向范围视野与优化启发函数的各蚁群算法在四组实验中均能得到可行路径,验证了方法的有效性;本文算法求解的路径质量优于另外三种算法,在四组实验中分别提高了0.52%～4.95%、4.71%～5.39%、2.26%～13.11%、3.84%～9.16%;此外,在野外三维山地环境中,定向范围视野的搜索方式缩减了搜索...     

蒙阴县台上铁矿矿山地质环境保护与恢复治理

临沂市蒙阴县地处沂蒙山区,地形起伏大,山区峰高坡陡,矿产资源较丰富,近年来,受矿产开发、地下水开采、山区综合开发利用,交通与水利建设以及不利地质条件影响,局部地段地质灾害频繁发生,根据蒙阴县台上铁矿区的地质环境条件,结合矿山地质环境问题的实地调查,在综合分析的基础上进行影响评估,并有针对性地提出了恢复治理措施。     

基于地理国情普查的内部道路公共化选取研究

本文依据道路密度和道路面积率提出了基于街区的道路密度与道路面积率计算方法,并利用缓冲和叠置分析,计算并分析了基于街区内部道路公共化前后的道路密度和道路面积率变化情况,通过该方法能有针对性地选取街区中的内部道路,能促进道路的微循环,缓解交通问题,具有较强的可操作性,对内部道路公共化的实施具有指导意义。