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Influence of reconstruction techniques on PET/CT image quality and quantitative accuracy:a phantom study

Radiation Detection Technology and Methods 2024年第2期8卷 1171-1186页

作者： xuesong su Jianhua Geng Jianing Liu Fengshuo Liu Yichen Wu Rong Zheng Xuejuan Wang Department of Nuclear Medicine National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100021China

Purpose To investigate the influence of different reconstruction techniques on the quantitative accuracy and image quality of PET/*** The NEMA NU2-2018 image quality phantom was scanned on a GE Discovery Elite PET/CT scanner and the spatial resolution was measured based on NEMA NU2 *** same raw data were reconstructed using five different algorithms:ordered subset expectation maximization(OSEM),OSEM with point spread function(PSF)modeling,OSEM with time-of-flight(TOF),OSEM with TOF and PSF,and filtered back-projection(FBP).The recovery coefficient(RC),contrast recovery coefficient(CRC),and contrast-to-noise ratio(CNR)were calculated for the six hot spheres,the percent background variability(PBV)and coefficient of variation(COV)were calculated for the background,and the residual error(RE)was calculated for lung insert in different image *** The incorporation of PSF modeling showed the smallest transverse FWHM and FWTM at both 1 and 10 cm radical *** combination of PSF modeling and TOF improved RCmean and CRC for all spheres and resulted in the highest ratings for the detectability of 10 mm spheres in human observer *** modeling played a role in reducing the COV within the background region of interest and increasing the CNR of the spheres,and decreased background noise ratings in human observer ***,TOF significantly reduced the RE in lung *** PSF modeling nor TOF had a significant effect on *** to FBP,the OSEM algorithm showed significant advantages in PBV,COV,CNR and RE and human observer ratings of image quality,but worse results for RC_(max),RC_(mean) and *** The integration of TOF and PSF modeling into the OSEM algorithm achieves improvements in both quantitative accuracy and image quality,providing distinct *** modeling improves the spatial resolution and decreases the visual appearance of background *** OSEM algorithm shows significantly better image qu

关键词： Positron emission tomography(PET) Image quality Quantification accuracy Reconstruction techniques Phantom

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Construction Technology of Large-deformation High Geostress Soft Rock Tunnel

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Journal of World Architecture 2021年第1期5卷 30-32页

作者： Xuguang Zheng Heng Zhang xuesong su China Merchants Chongqing Communications Technology Research&Design Institute CO. LTD.Chongqing 400067China Chongqing Rail Transit(Group)Co. Ltd.Chongqing 401120China

In the process of tunnel construction,if large-deformation occurs in high geostress soft rock,it will likely cause geological *** situation will not only seriously affect the smooth progress of tunnel construction,but also cause serious safety threat to the construction ***,with the continuous growth in the number and scale of tunnel construction in recent years,the construction technology for high geostress soft rock with large-deformation has begun to receive more and more attention from the *** on this,this paper takes an actual project as an example to analyze the specific application of the technology in order to improve the construction effect and avoid the damage caused by the large-deformation of the high geostress soft rock.

关键词： Tunnel construction High geostress soft rock Large-deformation Construction technology

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Safety Management Strategies for Cross-railway Interchange Widening Project in Highway Reconstruction and Extension

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Journal of World Architecture 2021年第2期5卷 22-25页

作者： Heng Zhang xuesong su Xuguang Zheng China Merchants Chongqing Communications Technology Research&Design Institute Co. Ltd.Chongqing 400067China Chongqing Rail Transit(Group)Co. Ltd.Chongqing 401120China

Under the background of rapid social and economic development,the traffic volume of highways has increased,which has brought tremendous pressure to the old *** response to this situation,the original highway must be reconstructed and *** is necessary to focus on the analysis and exploration of the methods of interchange reconstruction and extension in current highway reconstruction and extension to avoid affecting normal traffic,as it will inevitably have an impact on the traffic operation *** this situation,it is necessary to analyze and understand the format and characteristics of traffic organization of the interchange operation area in time and propose corresponding safeguard measures.

关键词： Highway reconstruction and extension Cross-railway overpass Widening project Safety management strategy

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Construction Safety Management and Construction Technology of Low-gas Tunnels

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Journal of Architectural Research and Development 2021年第2期5卷 44-47页

作者： Xuguang Zheng Heng Zhang xuesong su China Merchants Chongqing Communications Technology Research&Design Institute Co. Ltd.Chongqing 400067China Chongqing Rail Transit(Group)Co. Ltd.Chongqing 401120China

With the coordinated development of social economy and technology today,various advanced construction techniques and well-established management measures have begun to be widely used in coal-tunnel ***,in the construction process of low-gas tunnels,it will also cause a certain degree of adverse impact on the construction quality and safety due to the lack of technical experience and management experience to a certain *** on this,this paper takes the actual tunnel project of a coal mine as an example to analyze the main construction technology and safety management measures of low-gas tunnels,so as to provide guarantee for the quality and safety of such tunnel construction.

关键词： Low gas Tunnel construction Construction technology Safety management

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基于超高速开关和串联谐振的冗余保护型故障限流器

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高压电器 2018年第12期54卷 89-95页

作者：苏雪松大秦铁路股份有限公司大同西供电段山西大同037005

针对牵引供电系统供电安全可靠性要求高、短路电流冲击频繁的特点,提出一种具有冗余保护的故障限流器拓扑结构,通过互锁开关将设计的两个保护支路并联,在功能上二者均可单独实现故障电流的限制。其中保护支路I作为正常运行保护回路,采... 详细信息

针对牵引供电系统供电安全可靠性要求高、短路电流冲击频繁的特点,提出一种具有冗余保护的故障限流器拓扑结构,通过互锁开关将设计的两个保护支路并联,在功能上二者均可单独实现故障电流的限制。其中保护支路I作为正常运行保护回路,采用双分裂电抗器并联电容器和电抗器构成并联谐振回路;保护支路II采用超高速开关与电抗器并联。正常情况下保护支路I投运,保护支路II热备,主控制器通过实时监测系统电流和保护支路I的状态控制保护支路II投切。样机测试表明,该限流器能够在断路器动作之前监测到故障电流并动作,在最大程度上起到了限流作用。

关键词：超高速开关串联谐振故障限流器高频电流传感器冗余保护

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Factors affecting the distribution of microplastics in soils of China

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Frontiers of Environmental Science & Engineering 2023年第9期17卷 157-176页

作者： Yin Liu Matthias CRillig Quan Liu Jingjing Huang Muhammad Amjad Khan Xiaohui Li Qin Liu Qingqing Wang xuesong su Linyi Lin Yang Bai Genmao Guo Yi Huang Yong Sik Ok Shan Hu Junfeng Wang Honggang Ni Qing Huang Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province/Center for Eco-Environmental Restoration Engineering of Hainan Province/State Key Laboratory of Marine Resource Utilization in South China Sea/College of Ecology and Environment Hainan UniversityHaikou 570228China Institute of Biology Ecology of PlantsFreie Universität Berlin/Berlin Brandenburg Institute of Advanced Biodiversity Research(BBIB)Berlin 14195Germany Hainan Inspection and Detection Center for Modern Agriculture Haikou 570100China Institute of Environment and sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081China China College of Management and Economics Tianjin UniversityTianjin 300072China College of Environmental Sciences and Engineering Peking UniversityBeijing 100871China Korea Biochar Research Center APRU Sustainable Waste Management Program&Division of Environmental Science and Ecological EngineeringKorea UniversitySeoul 02841Republic of Korea School of Urban Planning and Design Peking University Shenzhen Graduate SchoolShenzhen 518055China

Microplastics(MPs)are found worldwide in high abundance,posing a potential threat to *** the ubiquity of MPs in the environment,very little is known about the regional distribution of MPs and underlying factors affecting this distribution in the field,which likely include human activity,but also features of the environment ***,out of a total of 1157 datapoints investigated in 53 Chinese studies,9.68%datapoints were removed as outliers in the heterogeneity *** review revealed that the abundance of MPs was highly *** addition,microplastic(MP)distribution maps based on China demonstrated that the highest abundance of MPs tended to occur near large rivers and central land affected by the intersection of two *** model-fitting and previous studies showed that MP abundance in China was correlated with longitude,agricultural mulching film usage per capita,temperature,and ***,due to the heterogeneity of MPs and the low matching degree between the current environmental data and the sampling points,this pattern was not as evident as reported in any single *** affecting the distribution of MPs can not be captured by linear relationships alone,and systematic selection of suitable environmental factors and further model optimization are needed to explore the cause of MP pollution in ***,this review revealed an uneven distribution of MPs and serves as a reference for model prediction to assess and control plastic pollution in natural soil environments.

关键词： Microplastic distribution Microplastic heterogeneity Effecting factors Agriculture Socio-economic factors

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Non-Rigid Medical Image Registration with Joint Histogram Estimation Based on Mutual Information

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Transactions of Tianjin University 2007年第6期13卷 452-455页

作者：陆雪松张素苏和陈亚珠 Department of Biomedical Engineering Shanghai Jiao Tong University

A mutual information-based non-rigid medical image registration algorithm is presented. An approximate function of Hanning windowed sinc is used as kernel function of partial volume (PV) interpolation to estimate the joint histogram, which is the key to calculating the mutual information. And a new method is proposed to compute the gradient of mutual information with respect to the model parameters. The transformation of object is modeled by a free-form deformation (FFD) based on B-splines. The experiments on 3D synthetic and real image data show that the algorithm can converge at the global optimum and restrain the emergency of local extreme.

关键词： non-rigid registration free-form deformation (FFD) Hanning windowed sinc partial volume (PV) interpolation

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模拟核医学临床成像模体及其性能评价进展

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中华放射医学与防护杂志 2023年第7期43卷 564-571页

作者：苏雪松耿建华国家癌症中心、国家肿瘤临床医学研究中心、中国医学科学院北京协和医学院肿瘤医院核医学科北京100021

核医学成像设备的质量控制是保障核医学成像质量和安全的必备工作,模体是核医学成像设备质量控制、性能比较、多中心临床试验等领域中不可缺少的工具。模体从结构单一向模拟临床真实条件发展,结合现代化技术提供不同的形式。不同种类模... 详细信息

核医学成像设备的质量控制是保障核医学成像质量和安全的必备工作,模体是核医学成像设备质量控制、性能比较、多中心临床试验等领域中不可缺少的工具。模体从结构单一向模拟临床真实条件发展,结合现代化技术提供不同的形式。不同种类模体具有独特的优势与适用情形。本文通过调研并综述核医学成像所用的常用模体及性能评价指标,为核医学设备质量控制及临床科研选用模体提供参考。

关键词：模体核医学成像模拟临床性能

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应用LAMSC无功补偿装置改善铁路牵引变电所功率因数

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电工技术 2008年第10期 9-10,12页

作者：苏雪松大秦铁路股份有限公司大同西供电段电力技术科山西大同0370057

阐述应用LAMSC降压智能投切电容器组有效跟踪牵引负荷的动态无功潮流变化,及时控制无功补偿装置输出的容性无功,可有效地提高牵引变电所的功率因数,改善供电质量,减小电网损耗,同时也可减少牵引负荷的谐波分量对电力系统的污染。

关键词：牵引变电所无功补偿谐波

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电渣熔铸一步成型曲轴质量研究

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钢铁 1983年第5期18卷 49-54页

作者：施璇范光前刘恒荣苏学嵩北京钢铁学院黎川特种铸钢厂

电渣熔铸一步成型新工艺又研制出了多拐曲轴。新工艺将精炼、铸造和整根曲轴的成型在同一设备中一次完成,省略了锻造或分段电渣铸焊。其力学性能已达到或超过了锻造曲轴。性能提高的主要因素是成分更均匀,纯净度更高,夹杂物更细小而分... 详细信息

电渣熔铸一步成型新工艺又研制出了多拐曲轴。新工艺将精炼、铸造和整根曲轴的成型在同一设备中一次完成,省略了锻造或分段电渣铸焊。其力学性能已达到或超过了锻造曲轴。性能提高的主要因素是成分更均匀,纯净度更高,夹杂物更细小而分散且呈球状分布,结构更均匀致密,枝晶间距也更细小,未发现低倍疏松与偏析等缺陷。与模锻曲轴相比时金属利用率提高了30％,工序少,投资少、成本低。

关键词：电渣熔铸晶轴轴间距力学性能模锻金属利用率电渣溶铸晶种力学性质锻造电渣锭传动轴曲轴

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