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Food Quality and Safety 2020年第1期4卷 21-28页

作者： bowen tai Jinghua Chang Yang Liu Fuguo Xing Key Laboratory of Agro-Products Quality and Safety Control in Storage and Transport Process Ministry of Agriculture and Rural Affairs/Institute of Food Science and TechnologyChinese Academy of Agricultural SciencesBeijing College of Science Liaoning Technical UniversityFuxinP.R.China

The contamination of Aspergillus flavus and subsequent aflatoxins(AFs)has been considered as one of the most serious food safety problems due to their acute and chronic adverse effects on humans and animals.This review collects the available information from recent years on the effect of the major environmental factors such as water activity(a_(w)),temperature,CO_(2),and pH on the fungal growth,the expression of AFs-related genes,and AFs production by A.flavus on foods.In particular,the relationship between the relative expression of key regulatory(aflR and aflS)and structural genes(aflD,aflO,aflQ,etc.)and AFs production under different environmental conditions are collected and discussed.The information collected in this review can be used to design control strategies of A.flavus and AFs contamination in practical applications,primarily during storage and processing.These data suggest that integrating various post-harvest methods with synergistic functions may be more efficient for the control of A.flavus growth and AFs production,although the individual environmental factors alone have an impact.

关键词： Aspergillus flavus aflatoxin water activity temperature CO_(2)

Summary of research on frost heave for subgrade in seasonal frozen ground

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Research in Cold and Arid Regions 2021年第3期13卷 195-205页

作者： Shuang Jia bowen tai ShouChen Qi Lei Li Tao Chen School of Hydraulic and Electric Power Heilongjiang UniversityHeilongjiangHarbinHeilongjiang 150086China State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China The Fourth Engineering Co. Ltd.China Railway 14th BureauThe Fourth Engineering Co.Ltd.China Railway 14th BureauJinanShandong 250000China

The building of railways on seasonally frozen ground is inevitable as China pursues economic development and the improvement of its citizens'living standards.However,railway construction in seasonally frozen soil areas is often faced with frost heave,leading to uneven subgrades which seriously threaten traffic safety.This article summarizes extant research results on frost heave mechanism,frost heave factors,and anti-frost measures of railway subgrades in seasonally frozen soil areas.

关键词： seasonal frozen ground railway subgrade frost heave anti-frost measures

Analysis of temperature field characteristics based on subgrade site measurements of Harbin-Qiqihar High-speed Railway in a deep seasonal frozen soil region

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Research in Cold and Arid Regions 2015年第5期7卷 547-553页

作者： ZuRun Yue bowen tai TieCheng Sun Graduate School Shijiazhuang Tiedao University School of Civil Engineering Shijiazhuang Tiedao University School of Civil Engineering Beijing Jiaotong University

Recent years have seen a large number of high-speed railways built and will be built in seasonal frozen soil regions ot China. Although high-speed railways are characterized by being fast, comfortable and safe, higher standards for defor- mation of the railways＇ frozen subgrade are required. Meanwhile, changes in subgrade soil temperatures are the main factors affecting the deformation of frozen subgrade. Therefore, this paper selected typical test subgrade sections of the Harbin-Qiqihar Line, a special line for passenger transport built in the deep seasonal frozen soil regions of China, to monitor field temperatures. Also, the temperature changing laws of railways＇ subgrade in this region was analyzed by using testing data, the aim of which is to provide a technical support for future design and construction of buildings and structures in a deep seasonal frozen soil region.

关键词： temperature field deep seasonal permafrost soils railways subgrade

Study on the sunny-shady slope effect on the subgrade of a high-speed railway in a seasonal frozen region

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Research in Cold and Arid Regions 2015年第5期7卷 513-519页

作者： QingZhi Wang bowen tai ZhenYa Liu JianKun Liu School of Civil Engineering Beijing Jiaotong University

The temperature distributions of different parts of a subgrade were analyzed based on the results of three years of moni- toring data from the Harbin-Qiqihaer Passenger Dedicated Line, a high-speed railway, including the slope toes, shoulders, and natural ground. The temperature variation with time and the maximum frozen depths showed that an obvious sun- ny-shady effect exists in the railway subgrade, which spans a seasonal frozen region. Development of frost heave is af- fected by the asymmetric temperature distribution. The temperature field and the maximum frozen depths 50 years after the subgrade was built were simulated with a mathematical model of the unsteady phase transition of the geothermal field.

关键词： high-speed railway sunny-shady slope effect frost heave temperature field

Temperature monitoring of the XPS board insulated subgrade along the newly constructed Gonghe-Yushu Highway in permafrost regions

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Research in Cold and Arid Regions 2015年第5期7卷 520-527页

作者： bowen tai JianHong Fang Lei Liu AnHua Xu JianKun Liu Ya Hu Tian School of Civil Engineering Beijing Jiaotong University Institute of Communications Science Qinghai Province

On the basis of on-site measured data of the newly constructed Gonghe-Yushu Highway in a permafrost region, this paper analyzed thermal conditions of the subgrade with XPS insulated board according to different selected monitoring sections in various locations. We also summarized the geothermal distribution and change rules of subgrade with XPS insulation board under the asphalt pavement in summarized a high temperature frozen soil region. It is suggested that the shoulder of subgrade with XPS insulation board be widen to a reasonable width so as to keep the subgrade stable.

关键词： permafrost highway XPS insulation board ground temperature

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基于双重注意力和分层感知表征的IQA方法

天津大学学报（自然科学与工程技术版） 2024年第3期57卷 234-243页

作者：史再峰佟博文孔凡宁康泰罗韬天津大学微电子学院天津300072 天津市成像与感知微电子技术重点实验室天津300072 天津大学智能与计算学部天津300072

图像质量评价在图像处理领域有着广泛的应用.基于深度学习的方法以多通道特征的形式获取图像信息,但在特征下采样过程中会丢失局部空间细节,导致对于图像信息的表征能力不足.针对以上问题,本文基于人类视觉系统的分层感知机制,提出了一... 详细信息

图像质量评价在图像处理领域有着广泛的应用.基于深度学习的方法以多通道特征的形式获取图像信息,但在特征下采样过程中会丢失局部空间细节,导致对于图像信息的表征能力不足.针对以上问题,本文基于人类视觉系统的分层感知机制,提出了一种全参考图像质量评价方法,采用Siamese结构的卷积神经网络实现非线性映射,从不同尺度和视觉复杂度表征图像信息,并通过双重注意力模拟人类在评价图像质量时对视觉注意力的调控过程.此方法在特征提取阶段引入空间注意力机制,对特征图的二维空间位置赋以权重,计算人在感知图像失真信息时对空间区域的注意力差别.在特征融合阶段利用分组通道注意力模块显式建模通道间的依赖关系,对感知差异特征进行自适应的校准,使网络关注对于图像质量评价影响大的通道特征.实验结果表明,该方法在LIVE、TID2013和CSIQ 3个公开数据集上的斯皮尔曼相关系数分别达到0.975、0.938和0.963,在应对复杂失真类型图像时的性能提升显著,与人类主观评价的一致性良好.

关键词：图像质量评价卷积神经网络双重注意力机制分层感知表征

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冻融循环对含砂粉土力学性质的影响

哈尔滨工业大学学报 2018年第3期50卷 135-142页

作者：刘晖刘建坤邰博文房建宏北京交通大学土木建筑工程学院北京100044 青海省交通科学研究院多年冻土区公路建设与养护技术交通行业重点实验室青海研究观测基地西宁810000

为了探究多年冻土区地表层的土体在冻融循环过程中力学性质的变化,通过对不同环境冷却温度、压实度、冻融循环次数、含水率和围压下的含砂粉土试样进行室内不固结不排水三轴试验,研究冻融循环后土体应力-应变关系曲线、破坏强度、弹性... 详细信息

为了探究多年冻土区地表层的土体在冻融循环过程中力学性质的变化,通过对不同环境冷却温度、压实度、冻融循环次数、含水率和围压下的含砂粉土试样进行室内不固结不排水三轴试验,研究冻融循环后土体应力-应变关系曲线、破坏强度、弹性模量、抗剪强度参数的变化规律,然后借助正交试验的显著性分析理论,研究以上因素以及各因素间交互作用对破坏强度和弹性模量的影响程度.结果表明:含砂粉土的破坏强度和弹性模量随冻融循环次数增加,在围压300 k Pa或冷却温度-5℃的情况下呈先增加后减小最后稳定的趋势,且在冻融循环3次后达到最大值;随冻融循环次数的增加,内摩擦角在冷却温度为-5℃的情况下逐渐减小并趋于稳定,在冷却温度为-10℃和-15℃的情况下先增加后减小最后趋于稳定;围压、含水率、压实度、冻融循环次数对破坏强度和弹性模量影响显著,冷却温度的影响较弱,压实度和含水率、冻融循环次数和围压的交互作用对破坏强度影响显著.综上分析得出,在研究冻融循环对土体力学性质的影响时应综合考虑各因素及其之间的交互作用.

关键词：冻融循环破坏强度弹性模量抗剪强度参数显著性分析

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寒区高速铁路路基冻胀数值模型及防冻胀措施

中国铁道科学 2017年第3期38卷 1-9页

作者：邰博文刘建坤李旭岳祖润沈宇鹏北京交通大学土木建筑工程学院北京100044 石家庄铁道大学研究生学院河北石家庄050043

寒区高速铁路路基的冻胀融沉直接影响列车的高速、安全和平稳运行。基于非饱和土渗流和热传导理论,将冻土水分场和温度场耦合,建立冻土的水热耦合微分方程;基于土体冻胀为各向同性的体积膨胀并且与材料的热膨胀现象相似,建立路基的冻胀... 详细信息

寒区高速铁路路基的冻胀融沉直接影响列车的高速、安全和平稳运行。基于非饱和土渗流和热传导理论,将冻土水分场和温度场耦合,建立冻土的水热耦合微分方程;基于土体冻胀为各向同性的体积膨胀并且与材料的热膨胀现象相似,建立路基的冻胀模型;由水热耦合微分方程计算含冰量,再通过水动力冻胀模型计算路基的冻胀变形。数值计算与实测的路基冻胀变形规律基本吻合,均在路基达到最大冻结深度且冻结层开始双向融化时产生冻胀峰值,验证了数值模型的有效性;运用建立的数值模型分别计算保温板路基、保温板+沥青混凝土路基和保温板+沥青混凝土路面+碎石路基在最强冻胀效应时刻的冻胀变形,保温板+沥青混凝土路面+碎石路基的冻胀变形最小(最大值为1.3mm),保温板路基的冻胀变形最大(最大值为3.2mm)。建议在寒区高速铁路采用保温板+沥青混凝土路面+碎石路基的结构以尽量减小路基的冻胀变形。

关键词：路基寒区冻胀数值模型冻结深度防冻胀措施高速铁路

冻融循环下含砂粉土冻胀率和融沉系数的试验研究

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铁道学报 2021年第9期43卷 118-126页

作者：沈宇鹏刘越邰博文汤天笑田亚护北京交通大学轨道工程北京市重点实验室北京100044 北京交通大学北京市轨道交通线路安全与防灾工程技术研究中心北京100044 中国科学院西北生态环境资源研究院冻土工程国家重点实验室甘肃兰州730000

以青藏高原东部共(和)—玉(树)高速公路玛多段地基的含砂粉土为研究对象,对含砂粉土在多因素(含水率、压实度、荷载)作用下的冻胀率及融沉系数的变化特征展开研究。在封闭系统条件下开展了三向冻融试验,总结了土样冻胀率及融沉系数的变... 详细信息

以青藏高原东部共(和)—玉(树)高速公路玛多段地基的含砂粉土为研究对象,对含砂粉土在多因素(含水率、压实度、荷载)作用下的冻胀率及融沉系数的变化特征展开研究。在封闭系统条件下开展了三向冻融试验,总结了土样冻胀率及融沉系数的变化规律;结合麦夸特法及全局优化法进行了优化计算,建立了预测稳定冻胀率和稳定融沉系数的计算模型。研究结果表明:冻胀率和融沉系数随荷载的增加、压实度的降低、含水量的增加而增加,随冻融次数的增加先增大后减小最后趋于稳定;建立的稳定冻胀率和稳定融沉系数预测模型有较好的拟合效果,因此可用此模型对含砂粉土的稳定冻胀率和稳定融沉系数开展预报。

关键词：冻胀率融沉系数冻融循环室内试验预测模型

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深季节冻土区哈齐客专路基现场试验

石家庄铁道大学学报（自然科学版） 2015年第1期28卷 66-70,110页

作者：邰博文岳祖润石家庄铁道大学土木工程学院河北石家庄050043 石家庄铁道大学道路与铁道工程安全保障省部共建教育部重点实验室河北石家庄050043

鉴于哈尔滨—齐齐哈尔(哈齐)客专路基工后沉降不大于15 mm的要求,开展了路基现场试验。对路基中的温度、沉降变形、路基冻胀变形及路基本体的含水量变化情况进行监测。结果表明:线路所处地区,11月中旬开始冻结,来年1月下旬地表附近地温... 详细信息

鉴于哈尔滨—齐齐哈尔(哈齐)客专路基工后沉降不大于15 mm的要求,开展了路基现场试验。对路基中的温度、沉降变形、路基冻胀变形及路基本体的含水量变化情况进行监测。结果表明:线路所处地区,11月中旬开始冻结,来年1月下旬地表附近地温过程线开始上抬;冻结层直到4月中旬才全部处于正温,最大冻深约为2.4 m。经过现场监测,处于深季节冻土区的高铁路基在经历冻融循环后的沉降变形为20 mm左右。路基表面的最大冻胀量发生在地表温度处于-1^-2℃之间,在此地温值下,路基冻结层范围内易发生水分积聚现象,路堤冻胀较敏感,所以路基填料应严格保持为最优含水量,做好基床表层的防排水措施,避免路基病害的发生。

关键词：地温沉降冻胀含水量