Analysis of Bridge Inspection Technology for Highway Reconstruction and Expansion

This article focuses on bridge testing technologies in highway construction and expansion projects.It provides an overview of the inspection process for bridges in highway reconstruction and expansion projects,the main inspections,and strategies for improving the quality of inspections.Relevant units should conduct bridge inspections using appearance inspections,special inspections,and bearing capacity assessments in highway reconstruction and expansion projects.To effectively improve testing quality,relevant units should also focus on establishing and improving testing standards,strengthening material testing,and improving the overall quality of the testing personnel.This research aims to enhance the quality of highway reconstruction and expansion projects by supporting the sensible application of bridge inspection technology.

Design Method for Road Reconstruction and Expansion

This article analyzes the method for designing routes in road reconstruction and expansion projects,using an actual engineering project as an example.This includes an overview of a specific road reconstruction and expansion project,an analysis of the preexisting road,the basic principles of the design road project,and an analysis of the design methods and steps.This study aims to offer some guidance for road reconstruction and expansion design.

Analysis and Comparison of Slope-cutting Widening Schemes in Highway Reconstruction and Expansion Project Based on MIDAS Software

In this paper,the geological condition of the right-side slope of the K114+694–K115+162 section of Yong-tai-wen Expressway is investigated and analyzed with the results showing that the strength of rock mass is the main contributor to the stability of the slope.Then,two widening schemes are proposed,which are the steep slope with strong support and the gentle slope with general support schemes.The static/slope module of MIDAS GTS finite element analysis software and the strength reduction method were used to compare the two schemes.The results show that the steep slope with a strong support scheme has obvious advantages in land requisition,environmental protection,and safety and is more suitable for reconstructing and expanding the highway slope.

Settlement Control Standards of Construction and Expansion for Mountainous Highway Roadbeds

This article analyzes the differential settlement of new and old roadbeds after widening and its characteristics based on a highway reconstruction and expansion project case study.The research proposes a subgrade settlement control standard that states that the maximum differential settlement value should be less than 5 cm when the embankment fill height exceeds 20 m.Similarly,the maximum differential settlement value should be less than 10 cm when the embankment fill height does not exceed 20 m.The findings of the study can provide a useful reference for the design of roadbed widening in highway reconstruction and expansion projects.

Toroidal Multipolar Expansion for Fast L-Mode Plasma Boundary Reconstruction in EAST

A new method for plasma boundary reconstruction, based on the toroidal multipolar expansion （TME） scheme, is applied successfully in EAST. TME applies a limited number of toroidal multipolar moments based on toroidal coordinates to treat a two-dimensional problem of axisymmetric plasma equilibrium. The plasma boundary reconstructed by TME is consistent with the results by using EFIT. The method is sufficiently reliable and fast for real time shape control.

ACCURATE DETECTION OF HIGH-SPEED MULTI-TARGET VIDEO SEQUENCES MOTION REGIONS BASED ON RECONSTRUCTED BACKGROUND DIFFERENCE

The paper first discusses shortcomings of classical adjacent-frame difference. Sec ondly, based on the image energy and high order statistic(HOS) theory, background reconstruction constraints are setup. Under the help of block-processing technology, background is reconstructed quickly. Finally, background difference is used to detect motion regions instead of adjacent frame difference. The DSP based platform tests indicate the background can be recovered losslessly in about one second, and moving regions are not influenced by moving target speeds. The algorithm has important usage both in theory and applications.

Analysis and Research on Interchange and Expansion options of Expressway

China's road network consists of numerous older expressways experiencing high traffic volumes and severe congestion,necessitating urgent reconstruction and expansion efforts.This study discusses the reconstruction and expansion project of the Yinkun Expressway's Chongqing High-tech Zone to Rongchang District section,with a detailed exploration of the entire design process.Through a comprehensive analysis,the strengths and weaknesses of different plans are examined,so as to determine the optimal plan.The design chosen saves costs while effectively addressing traffic demands.Additionally,the study summarizes the valuable design insights gained from this interchange transformation,aiming to provide valuable reference for similar interchange projects in the future.

基于α-expansion的超分辨率图像重建

为了获得更精确的超分辨率重建结果,在重建高分辨率像素时,剔除对重建贡献微弱甚至没有贡献的低分辨率像素,保留有所贡献的低分辨率像素。对低分辨率像素的贡献进行程度化,获得所有低分辨率像素的加权贡献,并进一步建立超分辨率重建的极小化能量函数,使用α-expansion算法求解能量函数极小化问题。在求解过程中,保留3个像素间的关系,可避免由能量函数的近似而引入的错误信息。实验结果表明,所提方法是合理、有效的。

Investigation on aerodynamic noise reduction for snow-plough of high-speed train

A set of acoustic optimization design methods is established by combining the flow field deterioration theory and the acoustic analogy theory,and applied to the acoustic optimization design of high-speed train snow-plough.The results show that the streamline bodies of the head/tail car are the most important sound sources,respectively,accounting for 23.7%and 33.7%of the total sound energy.Compared with the streamline body of tail head,the streamline body of head car is more biased towards high frequency for the sound source energy.The A-weighted radiated noise of the train body is characterized by broadband sound(mainly in the range of 1-4 kHz)and peak features(especially at 2 kHz).The snow-plough with the maximum expansion length can mitigate the strong peak effect of the sound at 2 kHz,reduce the total sound energy,and show the best acoustic radiation performance in the four schemes.The numerical computation model was checked by the wind tunnel test results.

Electromagnetic Tomography System for Defect Detection of High-Speed Rail Wheel

A novel electromagnetic tomography(EMT)system for defect detection of high-speed rail wheel is proposed,which differs from traditional electromagnetic tomography systems in its spatial arrangements of coils.A U-shaped sensor array was designed,and then a simulation model was built with the low frequency electromagnetic simulation software.Three different algorithms were applied to perform image reconstruction,therefore the defects can be detected from the reconstructed images.Based on the simulation results,an experimental system was built and image reconstruction were performed with the measured data.The reconstructed images obtained both from numerical simulation and experimental system indicated the locations of the defects of the wheel,which verified the feasibility of the EMT system and revealed its good application prospect in the future.

Deep learning-based time-varying channel estimation with basis expansion model for MIMO-OFDM system

For high-speed mobile MIMO-OFDM system,a low-complexity deep learning(DL) based timevarying channel estimation scheme is proposed.To reduce the number of estimated parameters,the basis expansion model(BEM) is employed to model the time-varying channel,which converts the channel estimation into the estimation of the basis coefficient.Specifically,the initial basis coefficients are firstly used to train the neural network in an offline manner,and then the high-precision channel estimation can be obtained by small number of inputs.Moreover,the linear minimum mean square error(LMMSE) estimated channel is considered for the loss function in training phase,which makes the proposed method more practical.Simulation results show that the proposed method has a better performance and lower computational complexity compared with the available schemes,and it is robust to the fast time-varying channel in the high-speed mobile scenarios.

Double Forehead Expanded Flaps for Reconstruction of Total Nasal Defect: A Case Report

Objective To introduce a method for total nasal defect reconstruction with a double forehead expanded flap.Case presentation A 55-year-old man underwent three-stage total nasal reconstruction for a complete nasal defect due to electrical injury.The skin expander was implanted during the 1st stage.Total nasal reconstruction was performed with double expanded forehead flap transfer during the 2nd stage.The unilateral forehead flap was used for lining and the contralateral forehead flap,together with the autologous cartilage and titanium mesh framework,were used for skin replacement.The forehead donor defect was covered with a skin graft.Pedicle division and inset were performed in the 3rd stage.Results There was no flap loss,infection,hematoma,rhinostenosis,or implant exposure over the 2-year follow-up,and satisfactory aesthetic results were achieved.Conclusion The double forehead expanded flap method is useful for the reconstruction of large composite nasal defects in patients who are not suitable for nasolabial flaps and those who may not tolerate free tissue transfer.The operation has fewer complications and is uncomplicated.

Application of Autologous Costal Cartilage Scaffold in Reconstruction of Microtia Ear

Objective To investigate the application effect and manufacturing skills of autologous costal cartilage scaffold in ear reconstruction for microtia.Methods From January 2016 to January 2019,41 patients with microtia reconstruction in our hospital were selected,all of whom were type II or type III pediatric deformities.All patients underwent auricle reconstruction and retroauricular skin expansion and autologous costal cartilage stent.The first stage of the operation is to insert a skin dilator behind the residual ear and inject water to expand.The second stage of the operation is to carve and repair the soft ribs(usually 6 or 7 ribs)from the body,make a three-dimensional auricle support for auricle reconstruction,place a negative pressure drainage tube,and follow up for 3 to 6 months to observe the three-dimensional shape of the reconstructed auricle and the formation of cranioauricular angle.Results 41 patients with microtia had good three-dimensional shape of auricle reconstruction,normal auricle position,moderate cranioauricular angle,good helix and triangular fossa structure,and good bilateral symmetry.Patients and their families were satisfied with the effect of auricle reconstruction.Conclusion Autologous costal cartilage is a good scaffold for auricle reconstruction.It is through efficient and elaborate carving and splicing that a good three-dimensional auricle structure can be formed.Combined with early flap expansion,a good postoperative appearance effect can be obtained,which is the appropriate method for auricle reconstruction at present.

改扩建高速公路桥梁可用性评判与延寿准则

针对高速公路改扩建工程中既有桥梁是否能继续使用问题,综合考虑总体技术状况、承载力状况、剩余耐久年限状况3个层次,创建了以桥梁构件类别的外观耐久状态为一级指标、以剩余耐久年限为二级指标的评判方法,提出了表征构件剩余耐久年限的寿命系数和可用寿命系数,建立了既有桥梁的延寿准则和延寿策略,探讨了可用寿命系数与目标使用年限、单次延寿的有效保护年限、拟采取的维护措施类型数量的相互关系。以京沪高速改扩建工程为研究背景,选取9座既有桥梁为典型桥梁,按100 a目标使用年限,计算得到构件主筋和箍筋的剩余耐久年限,给出了典型桥梁主体构件剩余耐久年限。根据可用评判方法,计算得到了在相同延寿措施下的延寿年限、延寿费用及可用寿命系数,按经济最优原则提出了从A级到E级共计5种延寿方式。研究表明,京沪高速改扩建工程典型桥梁按箍筋计算得到构件耐久寿命比按主筋计算值低,建议构件年限按箍筋计算值取用;目标使用年限为100 a时,主梁构件可正常使用比例为94%,墩柱单元、盖梁单元、桥台单元的可正常使用比例分别为67%,11%,44%。实际工程表明,采用该评判方法的评判结果与结构实际状态基本相符,与工程实际采取的处置措施基本相当,验证了该方法的合理性。

高温圆柱配合面接触热阻数值模拟研究

在众多核工程应用中,如燃料元件芯块与包壳的热力相互作用以及热管堆的传热过程中,界面接触热阻是热工分析的一个基础参数,也是传热系统温度分布预测的一个重要不确定性来源。准确预测和调控接触热阻可为系统的热防护和能量传递提供助益。本研究采用粗糙表面重构技术以及有限元热力耦合方法,对高温下的圆柱配合面结构进行热力耦合分析。本研究建立的数值预测方法能够应用于其它圆柱配合面的接触和传热预测,其方法和预测结果可为整个系统的热力耦合分析提供合理的分析方法和基础参数支撑。

文学阐释学:文化研究的挑战及其视域拓展

20世纪以来,众多新型理论观念纵横驰骋于文学阐释场域之中,持续制造了巨大的理论震荡。文化研究的崛起,不仅对文学阐释学构成了巨大的理论挑战,同时也为其发展赢得了开阔的阐释视野和强大的思想能量。文化研究的多元阐释观念和阐释方法同时也诱发出“过度阐释”“强制阐释”等问题。文化研究究竟是一种“强制阐释”,抑或是对阐释的有效拓展?显然,并不能将文化研究简单等同于“强制阐释”,辩证看待二者的关系意义重大。文化研究表明,强大的阐释能力对当代中国文学阐释学的理论更新和话语重构提供了有益的启示,展现出前所未有的活力。一方面,文化研究不仅推动了当代学界对文学阐释学的批判性反思;另一方面,文化研究促使我们将意义问题和文学阐释学置于更广阔的知识谱系中加以考察,进而推进当代中国文学阐释学的话语体系建设。

高速公路改扩建工程监理工作重点探讨

随着社会的发展和交通量的增加,高速公路改扩建工程逐渐增多。相比新建高速公路,高速公路改扩建工程具有时间紧、任务重、安全压力大等特点。旨在通过总结G5011芜湖至合肥高速公路芜湖至林头段改扩建工程监理过程经验,探讨高速公路改扩建工程在质量、安全、进度、合同等方面监理工作的重点,为大规模的高速公路改扩建工程监理提供有益的借鉴。

拼宽T梁桥的受力性能研究

文中基于桥梁博士有限元分析软件,以贵州山区拟建的3×30 m连续T梁桥拼宽工程为例,分别建立原桥和拼宽桥的有限元模型,定量分析桥梁拼宽前、后的横向分布系数,以及施工、运营下各梁片的力学响应变化规律。结果表明,紧邻拼宽部位的梁片内力和位移变化为10%~20%,其余梁片内力与位移变化均未超过4%。

基于裂变矩阵的谐波计算及其在气冷微堆功率监测中的应用

气冷微堆受限于堆芯体积及堆内高温高辐照运行环境,仅能布置少量堆外探测器用于功率监测。采用基于裂变矩阵产生高阶谐波的谐波展开法进行堆芯功率重构。通过反应堆蒙特卡罗程序RMC统计裂变矩阵,使用瑞利商迭代法求解特征向量,构造高阶谐波库;将堆芯三维功率分布用高阶谐波展开,结合探测器响应矩阵,实现三维功率在线监测。进一步研究了温度、燃耗、控制棒棒位对功率重构精度的影响,结果表明:温度、燃耗变化的工况下,气冷微堆节块平均功率的重构值与蒙特卡罗模拟参考值之间的均方根相对误差小于3%,最大相对误差小于5%;控制棒棒位变化对重构精度的影响较大,通过采用临近棒位的谐波组进行功率重构,均方根相对误差小于3%。验证结果为气冷微堆在线监测系统的后续研发提供参考。

改扩建工程路基差异沉降研究综述

随着我国经济社会的快速发展及交通量的持续增长,早期建成的高速公路已经开始出现通行能力差、服务水平低等问题。为了解决这一问题,我国在近年来积极开展了高速公路的改扩建工作,目前已完成了多条高速公路的改扩建工程并投入运营,取得了显著成效。然而,高速公路的改扩建与新建公路有所不同,高速公路在改扩建过程中涉及新老路基拼接、变形协调等问题,特别是新老路基拼接引起的差异沉降,对路基路面结构危害巨大。为此,国内外学者致力于对减小新老路基差异沉降进行研究,探索了许多新的理念和技术。从差异沉降的理论、影响因素以及路基拼接处的处治措施3方面对现有研究成果进行了回顾和梳理,发现对减小新老路基差异沉降的措施,尤其是对加筋结构的布置、路基内部排水结构的研究还比较缺乏。建议开展此类研究,并从理论和影响因素上对差异沉降进行分析,提出适用于多种工况的拼接措施,从而起到控制差异沉降的作用,旨在为实际工程项目提供理论和实际指导。