Detection of broken manhole cover using improved Hough and image contrast

The damage or loss of urban road manhole covers may cause great risk to residents＇ lives and property if they cannot be discovered in time. Most existing research recommendations for solving this problem are difficult to implement. This paper proposes an algorithm that combines the improved Hough transform and image comparison to identify the damage or loss of the manhole covers in complicated surface conditions by using existing urban road video images. Focusing on the pre-processed images, the edge contour tracking algorithm is applied to find all of the edges. Then with the improved Hough transformation, color recognition and image matching algorithm, the manhole cover area is found and the change rates of the manhole cover area are calculated. Based on the threshold of the change rates, it can be determined whether there is potential damage or loss in the manhole cover. Compared with the traditional Hough transform, the proposed method can effectively improve the processing speed and reduce invalid sampling and accumulation. Experimental results indicate that the proposed algorithm has the functions of effective positioning and early warning in the conditions of complex background, different perspectives, and different videoing time and conditions, such as when the target is partially covered.

Micro-dynamic Behavior and Self-adjusting Water Transmit Mechanism of Water-transferring Composite

Constructional and micro-dynamic process of the water-transferring composite was analyzed. This composite can transmit water to soil with a self-adjustable speed to ensure the survival of seedlings in arid and semi-arid regions when it is embedded in soil around the roots of the seedlings. It is obtained from natural plant fiber coated with a colloid made by mixing a certain proportion of polyacrylamide and montmorillonite. The rules of water being transmitted to soil by the coating under different condition were tested by M-30 quick moisture measure instrument. The process of water-desorption of the coating material was investigated by a Perkin Elmer Diamond S Ⅱ thermal multi-analyzer. Moreover, the micro-dynamic behavior was detected by a FEIQuanta 2000 environment scanning electron microscope. The results demonstrate that montmorillonite has lower water-desorption energy barrier than polyacrylamide and can lose water more easily. montmorillonite particles bridge up to be the main water-transmit material at low water potential （when the soil relatively dry or when the temperature is high）, and they break bridge at high water potential while the polyacrylamide acts as the main water-transmit material.

Self-adjusting decision feedback equalizer for variational underwater acoustic channel environments

Aimed at the abominable influences to blind equaliza-tion algorithms caused by complex time-space variability existing in underwater acoustic channels, a new self-adjusting decision feedback equalization （DFE） algorithm adapting to different under-water acoustic channel environments is proposed by changing its central tap position. Besides, this new algorithm behaves faster convergence speed based on the analysis of equalizers’ working rules, which is more suitable to implement communications in dif-ferent unknown channels. Corresponding results and conclusions are validated by simulations and spot experiments.

Use of Scrapped Rubber Tires for Sustainable Construction of Manhole Covers

Scrapped tires from vehicles are produced in large quantities. Despite numerous existing uses of scrapped tires, alarge quantity ends up at the landfill sites, which contributes to environmental degradation. The development ofmore applications of scrapped tire usage can reduce the disposal of tires at landfill sites. This research proposes anovel use of scrapped tires by using the strips taken from scrapped tires in replacement of steel bars as reinforcement. Manhole covers were produced using scrapped tires by completely replacing the steel with scrapped tires.Four different samples of manhole covers were prepared and tested. The highest bearing capacity of 25.5 kN wasrecorded with a sample of 100 mm thickness made with cementitious composite, which is 2.25 times higher thanthe bearing capacity of a conventional reinforced-concrete manhole cover. The use of manhole covers made withscrapped tires can effectively address the theft issue of manhole covers. The lifecycle cost analysis shows that themanhole cover made with scrapped tires is 3.4 times more cost-effective in comparison with the conventionalmanhole cover. This research shows a new avenue of the potential use of scrapped tires as reinforcement in structures, which can improve sustainable construction practices.

Experimental study on countermeasure against liquefaction-induced flotation of manhole using recycled materials packed in sandbags

The 2004 Niigata-ken Chuetsu earthquake in Japan caused serious damage to sewage facilities such as uplift of manholes and settlement of pavement above backfill soil for pipes.This paper deals with shake table tests in a 1 g gravity field on application of recycled materials for ground improvement to mitigation of liquefaction-induced flotation of manhole during earthquakes.The recycled materials used in tests were tire chips made of waste tires and crushed gravels made of waste reinforced concrete,and they were packed in sandbags.From the test results,it was confirmed that the recycled materials packed in sandbags could be treated as one of the countermeasures to restrain the flotation of manholes and settlement of ground surrounded by sandbags.

The Design of Urban Road Manhole Covers Based on the Function of Safety and Identification

This study combed the development process of urban road manhole cover at home and abroad,and pointed out the existing problems in the domestic manhole cover.From the perspective of safety and identification function,it put forward innovative design ideas of urban road manhole covers to improve the safety and identification function of road manhole covers,and enhance the ornamental of manhole covers.

Traffic prediction using a self-adjusted evolutionary neural network

Short-term prediction of traffic flow is one of the most essential elements of all proactive traffic control systems.The aim of this paper is to provide a model based on neural networks(NNs)for multi-step-ahead traffic prediction.NNs'dependency on parameter setting is the major challenge in using them as a predictor.Given the fact that the best combination of NN parameters results in the minimum error of predicted output,the main problem is NN optimization.So,it is viable to set the best combination of the parameters according to a specific traffic behavior.On the other hand,an automatic method—which is applicable in general cases—is strongly desired to set appropriate parameters for neural networks.This paper defines a self-adjusted NN using the non-dominated sorting genetic algorithm II(NSGA-II)as a multi-objective optimizer for short-term prediction.NSGA-II is used to optimize the number of neurons in the first and second layers of the NN,learning ratio and slope of the activation function.This model addresses the challenge of optimizing a multi-output NN in a self-adjusted way.Performance of the developed network is evaluated by application to both univariate and multivariate traffic flow data from an urban highway.Results are analyzed based on the performance measures,showing that the genetic algorithm tunes the NN as well without any manually pre-adjustment.The achieved prediction accuracy is calculated with multiple measures such as the root mean square error(RMSE),and the RMSE value is 10 and 12 in the best configuration of the proposed model for single and multi-step-ahead traffic flow prediction,respectively.

Self-adjustment of Carrying Capacity of Concrete Embedded with CFRC

By heating up the embedded carbon fiber reinforced cement based material （CFRC）, the carrying capacity and deformation of concrete member could be adjusted. The relationship between temperature difference and expansion strain of CFRC was demonstrated, and the temperature-deformation-load effect of concrete embedded with CFRC was studied. Heating the CFRC up to different temperatures resulted in different degree of inner pre-stress in concrete. Thus, the load capacity of concrete could be regulated owing to counteracting the pre-stress.

基于Self-adjust网络模型的人脸图像情感分析方法

人脸表情具有丰富的情感内涵,是情感分析的一个重要研究方向。模糊的面部表情及标注者的主观性所带来的不确定性,给情感分析研究带来了挑战。鉴于此,提出了一种基于Self-adjust网络模型的人脸图像情感分析方法。首先用人脸对齐方法进行图像预处理,然后利用注意力机制来处理Focal损失加权,再对其进行秩正则化排序,最后通过重新分类对有误标签进行矫正,并用实验验证了该方法的有效性与优越性。该方法在准确率这个评价指标上有所提高,能够有效抑制人脸图像情感分析的不确定性,防止深层网络对不确定的人脸图像进行过拟合。

基于车载LiDAR数据的城市道路井盖提取与病害检测

使用传统的道路测量方法进行路面井盖病害信息的获取存在安全性差且效率低等问题,为了提高作业效率,本文提出基于移动车载激光扫描系统的路面井盖病害检测方法。首先,基于城市道路点云的反射特征及空间分布特征,提出使用一种基于布料模拟的滤波算法(Cloth Simulation Filter,CSF)进行地面点云提取;其次,使用自适应阈值方法对生成的点云强度图像进行二值化;最后通过限制参数的Hough圆检测方法实现井盖的定位与提取。以潍坊市潍城区某段道路点云数据进行试验,得出的结论为:提取井盖的平面精度为±0.048 m,井盖沉降残差值中误差为±0.0117 m,满足常规的井盖病害检测项目的精度要求。

雨水检查井概化对城市内涝一二维耦合模拟结果影响研究

为探明城市内涝一二维模型耦合过程中,检查井井盖对节点溢流和二维积水特征的影响,以重庆市悦来会展城某排水片区为研究区,耦合暴雨径流管理模型(Storm Water Management Model,SWMM)与有限体积海洋模型(Finite-Volume Coastal Ocean Model,FVCOM)。通过分析溢流过程中检查井井盖的作用水头,对耦合模型的溢流节点计算水头进行校正。基于历史降雨对模型进行验证,并应用耦合模型模拟分析不同井盖概化方式下溢流节点数量、位置分布、积水深度和积水面积的差异。结果表明:降雨重现期较小时(如低于50 a一遇),管网溢流程度较轻,两种井盖概化方式下的节点溢流情况无太大差别;与不考虑井盖影响相比,50 a和百年一遇时,模型中考虑井盖影响下的检查井溢流个数分别从533和597减少为189和431,最大积水深度分别从0.46 m和0.53 m下降到0.38 m和0.48 m,最大积水面积分别从3.50 km^(2)和3.85 km^(2)下降至2.10 km^(2)和3.05 km^(2);识别出3处主要易涝点,分别位于滨江路与同茂大道交汇处、悦城路北段和翠岗路南段末端。因此,在管网发达的城市区域构建一二维水动力耦合模型进行极端内涝风险模拟分析时,应充分考虑雨水检查井井盖在模型中合理的概化,提高模拟结果的准确度。

长距离输水管道自动化监控系统的设计与研究

为实现提高长距离输水管道远程调度、智能监控及安全监测之目的,本文在南水北调“北三县”供水工程中引入自动监控、视频监控、分布式光纤传感技术及智能井盖监测技术,并重点介绍了综合管控平台应用管理中管网漏损监测子系统与智能井盖监测子系统的工作原理。在综合管控信息化平台大数据的支撑下,实现了对供水工程内全要素及供水调度管理全过程的精准化、智能化监控,特别是,解决了长距离管网漏损的预警监测、故障定位及阀井井盖的实时状态监测、有限空间监控,对于供水工程的安全运行具有重大意义。

上海某市政道路污水管道设计的主要节点分析

市政道路污水管道设计一般基于当地已经批准的城市污水规划。随着城市的发展,市政道路下各类公用管线云集,在实际设计过程中,难免会遇到管线交叉、新老管道衔接等问题。为研究此类问题的解决方法,以上海市某市政道路污水管道设计为例,通过比较污水管道施工工艺、与华东路和川沙路污水管道衔接方案的优劣,确定了经济合理的解决方案,以期为今后类似项目的设计提供借鉴与参考。

基于废砖的农村污水处理型接户井参数优化研究

农村污水水量变化大,容易影响污水处理设施的正常运行,应用废砖构建农村污水处理型接户井能够实现污染控制前置,提高污水治理体系的稳定性,也能够实现农村建筑废弃物的资源化利用,前景广阔。但是,该技术的影响因素和参数选取尚不明确,影响其推广应用。为解决上述问题,采用小试和中试装置,结合材料表征、单因素分析和响应曲面分析等方法,对基于废砖的农村污水处理型接户井的废砖粒径影响、污染控制效果和参数优化过程开展研究。结果表明,基于废砖的农村污水处理型接户井具有良好的污水处理效果,0.5~<1.0 cm粒径的废砖碎块较为适用;填料高度、折流深度和跌水高度影响接户井的污染控制效果,随填料高度和折流深度的增加以及跌水高度的降低,污染物去除率升高;接户井在最优条件下的COD、悬浮物、氨氮、总氮和总磷去除率分别达58%、68%、60%、52%和58%,就地还田利用情景下填料高度宜为90 cm、折流深度宜为64 cm、跌水高度宜为12 cm。该研究可为农村污水的污染控制前置提供可行技术方案并为农村污水治理技术的进步提供参考。

船用人孔盖强度分析

为探究船用人孔盖的强度问题,以人孔盖和周围船体结构为研究对象,以散货船货舱段有限元模型为基础,建立包含人孔和人孔盖细化模型在内的典型计算模型。利用HCSR有限元计算工况分析人孔盖受力状态,综合分析人孔盖盖板、连接板和螺栓3个主要因素对人孔盖强度的影响,为人孔盖选型提供依据。

沥青路面检查井周边平整度施工质量控制

沥青路面检查井作为路面的一部分,但其与其他结构不连续,在动荷载作用下,井周易发生破坏,致使路面平整度不足,影响城市道路行车舒适性,甚至影响行车安全。检查井返修率高、难度大、成本高,需局部封闭交通。现以泰州市高港区高港大道改扩建工程为例,介绍沥青路面检查井周边平整度施工工艺。其成果可为同类型的工程施工提供借鉴和参考。

Dynamically self-adjustable liquid-liquid and self-adaptive softcontact solid-solid triboelectric nanogenerator for wave energy harvesting

Water wave energy exhibits great potential toalleviate the global energy crisis. However, harvesting andutilizing wave energy are challenging due to its irregularity,randomness, and low frequency. Triboelectric nanogenerators(TENGs) have gained significant attention for harvesting waveenergy with high efficiency. This study presents a novelellipsoidal, pendulum-like TENG integrating both liquid-liquid(L-L) and solid-solid (S-S) triboelectricity (LS-TENG). Thisinnovative design enables continuous wave energy harvestingand self-powered marine environment monitoring under variousconditions, including temperature, humidity, and light intensity. The binary immiscible liquids within the LS-TENG’s innersoft balloon create dynamic, and self-adjustable L-L contact interfaces, significantly increasing the L-L contact area andenhancing L-L contact electrification (CE). The unique self-adaptive, soft S-S contact increases the S-S contact areacompared to traditional hard point contact, better adapting to the irregular movements of waves and promoting efficient S-SCE. The LS-TENG achieves highly efficient wave energy harvesting by coupling L-L and S-S CE. Furthermore, the uniquesoft contact design protects the S-S interfaces from mechanical wear and damage during long-term work. The LS-TENG’snovel structure provides an innovative and effective way for water wave energy harvesting.

沈阳市青年大街工程自调式井盖设计及应用

城市道路上检查井盖存在的沉陷、破损及缺失等问题,既影响行车安全,又影响城市形象,已成为城市交通的一大痛点,备受广大市民关注。鉴于此,结合青年大街道路更新工程中自调式井盖(防沉降井盖)的应用,简要阐述了新型自调式井盖(防沉降井盖)的结构设计及优点。

基于情境感知的智能井盖多维交互系统设计

为改善窨井事故频发、监管困难的现状,研究主要的窨井故障情境与维管人员工作场景中的各种情境影响因素与问题,降低窨井相关事故的发生频率,提升维管人员发现并解决窨井问题的工作效率。通过用户调研的方式对窨井在实际应用和维管工作中出现的问题及用户需求进行总结分析,结合情境感知技术,有针对性地提出设计策略,并进行设计实践。构建智能井盖多维交互系统。研究成果将改善当前城市窨井维管困难、事故频发等问题,提高窨井维管人员的工作效率,为智能井盖及其管理系统的设计研究提供参考。

奎河截污管工程中轨道交通保护施工方案探讨

城市新建市政管道工程可能对临近的轨道交通隧道结构的安全运行产生影响。徐州市区奎河综合整治工程截污主干管工程建国西路~建国东路段上跨轨道交通地铁2#线盾构隧道,截污管管底距地铁盾构顶竖向净距最小仅6.1 m。依托该工程,总结介绍了顶管工程中针对轨道交通保护的工程施工安全质量保证措施及应急预案,旨在为类似工程提供借鉴和参考。