基于机器视觉的非接触式螺纹参数测量系统

文中采用光机电一体化的思想,将光源、CCD、计算机等有机结合,开发了一种基于面阵CCD技术的石油管螺纹参数智能化测量系统。生产现场测量结果表明：该系统具有重复性好、精度高、检测速度快等优点,此外,此系统具有抗环境光及振动干扰,可操作性强等特点,适用于各种规格钢管外螺纹参数的在线测量。     

RTK系统在西气东输二线数字化管道中的应用

随着RTK（Real Time Kinematic）系统的推广,该系统以高精度及操作便捷在石油管道建设中得到了广泛应用。叙述了该系统的基本工作原理及在西气东输二线管道工程施工中的应用情况。文中对该系统操作简单、数据处理能力强、作业效率高、无累计误差、测量精度高、不受自然条件影响等野外操作过程中的优点以及该系统在长输管道施工过程中存在的不足及应注意的问题进行描述。     

汽车四轮定位检测系统设计探讨

为了解决目前四轮定位中操作不便、精度低、线缆布局复杂、使用空间受限和价格昂贵等缺点,文章设计了基于ZIGBEE技术的汽车四轮定位检测系统,介绍了该系统的总体设计及硬件设计和软件设计实现的方法。结果表明,该系统能够正确、实时地显示测量结果,操作简单、灵活。     

线阵CCD油管螺纹测量系统程序开发

基于线阵CCD的油管外螺纹参数检测系统是一种先进的非接触式工业检测系统,包括硬件和软件两部分。针对该系统的重要组成部分———控制、计算程序的设计和开发进行了详细的阐述。该程序的开发基于Windows 2000,开发工具为C Builder 6.0,包括数据采集与存储、滤波、边界点选取、参数计算等多个模块。程序功能完整,界面友好,控制精确,计算结果能够满足测量系统的精度要求。     

RTK与全站仪联合应用于道路施工测量技术研究

施工测量是道路施工过程中的一个重要环节,测量放线的精度对工程质量、线路走向、竣工验收等环节产生重要的影响,研究RTK与全站仪联合应用于各种复杂工地环境下道路施工测量技术,能够将传统的控制测量和施工放样进行一站式操作,在复杂环境下道路工程的施工测量过程中,该测量系统具有科学性、先进性和实用性。     

公路路线测量PDA程序设计方法

利用PDA配合全站仪进行公路路线勘察测量可以大大提高工作效率.PDA测量程序利用VB.NET进行开发,其特点是程序可视化高,计算速度快,操作简便,使用方法与电脑操作类似;并且由于PDA存储量大,可对测量数据直接记录,减少内业工作量,摆脱了传统PC-E500及Casio-fx4800等测量方法的许多不足.文章介绍了该程序设计流程及方法.     

基于Labview的视觉盾尾间隙测量系统研究

盾尾间隙是管片选择的重要依据,间隙过小会造成盾尾与管片发生干扰,降低掘进速度;间隙过大浆液容易将盾尾脂冲破,造成漏浆。为了提高盾尾间隙测量的精准度,确保盾尾间隙变化量在允许范围内,文章研究了一种基于视觉处理的盾尾间隙测量系统,详细说明了整个系统的设计,重点介绍了采集照片后基于Labview的图像处理算法和二维卷积的边缘检测算法,介绍了Labview与PLC的通讯系统及其数据传输。研究结果显示,该测量系统操作方便、精准度较高。     

装配式大钢管支架在高架桥箱梁现浇中的应用

文章介绍了装配式大钢管支架的特点、适用范围及工艺流程,分析了装配式大钢管支架施工操作要点,并结合高架桥箱梁现浇施工应用实例,评述了装配式大钢管支架系统具有整体稳定性好、标准化程度高、质量安全性能强等特点。     

轨道交通接触轨/网“一键停送电”技术分析

传统的轨道交通接触轨/网停、送电操作方法具有步骤多、耗时长、易出错等弊端。以上海轨道交通16号线的接触轨停、送电操作为研究对象,提出了"一键停送电"技术。从理论基础、系统界面及操作、使用效果等方面介绍了该方法的创新性及实用性。     

基于DSP的先进视频交通数据采集系统探讨

DSP是一种先进的视频交通数据采集系统,它操作简单,不仅能够有效的融入于道路交通数据采集系统,还能够与感应式十字路口信号灯控制系统、电子警察抓拍系统相结合,其双重功用被广泛应用于城市道路、高速公路交通数据采集,以及公路隧道、桥梁的意外事故监控系统中,并且可以适应各种天气,具有全天候检测的能力。文章从系统特点、检测数据精度、系统的多功能性及系统操作的方便性等方面介绍了该系统的先进性、实用性。     

Definition of a merging assistant strategy using intelligent vehicles

In the area of active traffic management, new technologies provide opportunities to improve the use of current infrastructure. Vehicles equipped with in-car communication systems are capable of exchanging messages with the infrastructure and other vehicles. This new capability offers many opportunities for traffic management. This paper presents a novel merging assistant strategy that exploits the communication capabilities of intelligent vehicles. The proposed control requires the cooperation of equipped vehicles on the main carriageway in order to create merging gaps for on-ramp vehicles released by a traffic light. The aim is to reduce disruptions to the traffic flow created by the merging vehicles. This paper focuses on the analytical formulation of the control algorithm, and the traffic flow theories used to define the strategy. The dynamics of the gap formation derived from theoretical considerations are validated using a microscopic simulation. The validation indicates that the control strategy mostly developed from macroscopic theory well approximates microscopic traffic behaviour. The results present encouraging capabilities of the system. The size and frequency of the gaps created on the main carriageway, and the space and time required for their creation are compatible with a real deployment of the system. Finally, we summarise the results of a previous study showing that the proposed merging strategy reduces the occurrence of congestion and the number of late-merging vehicles. This innovative control strategy shows the potential of using intelligent vehicles for facilitating the merging manoeuvre through use of emerging communications technologies.     

Effectiveness of roadside crash countermeasures

In this article, an "intelligent" airline seat inventory control system is developed. Applications of the system are considered for both nonstop flights and flights with stopovers. The system developed is able to recognize a situation characterized by the number of reservations made by individual passenger classes and the number of canceled reservations at a certain moment in time before departure. The system can also make the appropriate decision without knowing the functional relationships in effect between individual variables. As in other intelligent systems, the "intelligent" airline seat inventory control system proposed here is able to generalize, adapt and learn based on new knowledge and new information. The "intelligent" airline seat inventory control system is based on fuzzy logic. The system makes on-line decisions as to whether to accept or reject any passenger request using established fuzzy rules. The "intelligent" system's results are compared with those of the EMSR model for nonstop flights. The results for flights with stopovers are compared with those obtained using integer programming. The final conclusions are very promising.     

Characteristics of gaseous and particulate pollutants exhaust from logistics transportation vehicle on real-world conditions

On-road vehicle tests of three heavy duty diesel trucks were conducted by a portable emission measurement system (PEMS) in Chengdu, China. SEMTECH-ECOSTAR provided by Sensors Inc. was employed to detect gaseous emissions and MI2, an emissions measuring instrument powered by the Pegasor Particulate Sensor (PPS) was used to detect particulate emissions during the tests. The impacts of speed, acceleration and engine load on emissions were analyzed. The average nitrogen oxides (NOx) emission factors of the heavy duty diesel truck (HDDT), medium-duty diesel truck (MDDT), light duty diesel truck (LDDT) were 7.29, 5.29 and 5.53 g/km. The particulate emission factors were 0.60, 0.30 and 0.14 g/km respectively, higher than the similar reported in the previous studies. Both gaseous and particulate emission exhibit significant correlations with the change in vehicle speed, acceleration and power demand. The highest emission was generally in high VSPs and higher loads. High engine load caused by aggressive driving was the main factor of high emissions for the vehicles on real-world conditions.     

The Japanese experience with mini‐cars

Despite the early appeal of the light vehicle, increases in the average annual income have allowed consumers to consider a broader range of vehicles so that the negative aspects of mini‐vehicles such as higher noise and vibration levels, the lack of horsepower and instability in certain driving conditions have made light vehicles less tolerable. The “oil shock” shattered economic projections, and people began to acknowledge that living in a world with limited resources was a harsh reality. Concurrently, congestion increased dramatically in urban areas as a result of the popularity of automobiles, and producers made a number of design changes to improve the safety and comfort limitations of light vehicles. Thus, in a world where fuel economy and ease of use gained a greater meaning, light vehicles slowly regained their original appeal.

Light vehicles may play a greater role in the future. Studies indicate that light vehicles tend to be driven by females and elderly people and current trends indicate that the number of female drivers is increasing and that the average age of the Japanese population is getting higher. Furthermore, migration patterns indicate that a greater number of people are moving to smaller cities and their outlying areas as a result of national decentralization policies. The migration pattern may popularize light vehicles because vehicle ownership rates are higher in these areas than in larger cities. Another development which may increase the popularity of light vehicles is that more families are owning more than one car and light vehicles are popular as second vehicles. Moreover, the prospects of low economic growth have tempered the importance of comfortable amenities, and the virtues of maneuverability and fuel economy have become more important.

     

Modeling access to public transport in urban areas

It is important to measure public transport accessibility to help improve the sustainability of transport systems in metropolitan areas. Although many studies have defined different approaches for measuring public transport accessibility, there have been limited methods developed for measuring accessibility levels that incorporate spatial aspects. Population density is an important distributional indicator that has also been ignored in previous methods developed for quantifying accessibility. This paper outlines the research context for measurement of public transport accessibility and then describes a methodology developed as well as an application the Public Transport Accessibility Index in Melbourne area, Australia. Using the Victorian Integrated Survey of Travel and Activity dataset, we applied separate‐ordered logit regression models to examine how the new index performs with a series of predictor variables compared with two existing approaches. Key findings indicate that there is a higher probability of public transport patronage in areas with higher levels of accessibility. Furthermore, it was found using statistical modelling that the new index produces better results compared with previous approaches. Copyright © 2016 John Wiley & Sons, Ltd.     

交通拥堵智能监测的车联网环境构建

车联网是互联网以及物联网通讯技术引入交通领域而发展出来的一类智能交通应用技术。本文在解析车联网基本架构体系的前提下,围绕交通拥堵智能监测的优化实现,基于V2V模型,构建一种智能监测的车联网典型应用环境,并参考车联网基本特征,探讨定义智能监测条件下的交通拥堵评价基准。     

Comprehensive Evaluation of the Intelligent Degree of the Mining Face Based on Grey Relational Analysis北大核心CSCD

In order to further evaluate the intelligent degree of the coal mining face scientifically and reasonably, this paper constructs a gray relational analysis based comprehensive evaluation model for the intelligent degree of mining face by deeply analyzing the influencing factors on the intelligent degree of mining face, such as surrounding rock detection, mining equipment, production system, supporting production system, organization and management, etc. By quantifying and scoring factors affecting the intelligence degree of mining face, using the hierarchical analysis method to obtain the weights and determine the correlations, the intelligence degrees of mining face are classified into four levels: excellent, good, medium and poor. Using the comprehensive evaluation model to empirically verify the 802 working face of Shaanxi Huangling Mining Co., Ltd., the calculated correlation is 0.765 8, which indicates that the intelligent degree of 802 working face is excellent according to the rating criteria, and it is consistent with the actual situation. Therefore, the comprehensive evaluation model based on gray relational analysis can accurately and objectively evaluate the intelligent degree of the mining face. © 2022, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

基于分布式计算机的智能相机在城市交通中的研究与应用

我国逐步开始将城市建设与互联网技术进行高度融合以打造智能城市。智能城市建设过程中,智能交通是重要一环,当前我国交通视频监控系统普遍是通过道路两旁的摄像头拍摄获得路况图像信息,这种方式虽然是解决了一些问题,但是不能满足智能城市的建设需求。本文总结和研究了分布式智能相机的一些关键技术,得出嵌入式设备高效率、低耗能的优点使其在交通监控领域得到了越来越广泛的应用,基于分布式计算机设计了智能相机的分布式智能城市交通系统,提出了一系列有益于提升系统运行的具有应用前景的算法,用来解决使用重叠视野进行跟踪和稀疏相机网络中的有效跟踪。     

Objectives,Methods and Results of Surveys Carried out in the Field of Urban Freight Transport: An International Comparison

In industrialized countries, the number of studies and surveys in the field of urban goods movement (UGM) has increased considerably over recent years. This paper compares the objectives, methods and results in this sector and focuses on nine industrialized countries of Europe, America and Asia. This non‐extensive review shows that in spite of different framework methods and models, similar trends emerge at the economic and environmental levels. It is necessary to take into account urban logistics in the broadest meaning of the term. Cooperative action seems to bear fruit providing that information and dialogue take place in the long‐term with all the operators involved. The development of intelligent transport systems (ITS) and better management of urban facilities may improve these attempts. We present our viewpoint in order to shed light on research oriented towards the sustainable management of urban logistics.