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单光子模式激光测高探测概率模型与精度分析

中国激光 2016年第11期43卷 229-234页

作者：黄科李松马跃周辉易洪史光远武汉大学光电子信息学院湖北武汉430072

单光子模式激光测高仪具有灵敏度高、重复频率高、重量轻、体积小等诸多优势,其代表着新一代天基激光雷达的未来发展趋势。对常见的高斯回波波形,基于激光雷达方程、单光子探测器统计特性,建立了单光子回波探测概率模型,基于该模型进一... 详细信息

单光子模式激光测高仪具有灵敏度高、重复频率高、重量轻、体积小等诸多优势,其代表着新一代天基激光雷达的未来发展趋势。对常见的高斯回波波形,基于激光雷达方程、单光子探测器统计特性,建立了单光子回波探测概率模型,基于该模型进一步推导了测距误差的量化关系式,并利用蒙特卡罗方法对所建模型进行了仿真验证。理论分析和仿真计算表明:回波脉宽越窄,测距的系统误差和随机误差越小;回波强度越大,测距的随机误差减小,但系统误差增大。以均方根脉宽为1.5ns的高斯回波为例,忽略噪声影响,当平均信号光子数为1时,单次测距系统误差约6cm,随机误差约22cm。

关键词：遥感激光测距测距精度蒙特卡罗方法单光子泊松分布

活化时间对化学镀Ni-P-Al_2O_3镀层组织及性能的影响

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电镀与环保 2018年第4期38卷 23-25页

作者：伍昊杨和梅陈可易光远南京农业大学工学院江苏南京210031

采用化学镀方法在45#钢基体上制备了Ni-P-Al_2O_3镀层,并研究了活化时间对镀层的组织结构、硬度、摩擦因数及耐蚀性的影响。结果表明:当活化时间由40s延长至120s时,镀层的表面组织都由胞状颗粒组成,组织变化由非均匀致密→均匀致密→不... 详细信息

采用化学镀方法在45#钢基体上制备了Ni-P-Al_2O_3镀层,并研究了活化时间对镀层的组织结构、硬度、摩擦因数及耐蚀性的影响。结果表明:当活化时间由40s延长至120s时,镀层的表面组织都由胞状颗粒组成,组织变化由非均匀致密→均匀致密→不均匀致密。当活化时间为80s时,镀层的组织最均匀致密,由Ni-P-Al_2O_3非晶胞构成,XRD图谱上没出现基体Fe的衍射峰,说明镀层较厚,完全覆盖基体。镀层的硬度、摩擦因数、耐蚀性均随活化时间的延长先增后减,活化时间为80s时制备的镀层硬度最高、摩擦因数最小、耐蚀性最好。

关键词：活化时间化学镀组织耐蚀性

高韧超薄沥青磨耗层在常德市武陵大桥中的应用

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北方交通 2023年第6期 35-38,42页

作者：易光远吴有威湖南省常德市城市桥梁管理处常德市415000 华运通达(广东)道路科技有限公司佛山市528399

为对常德市武陵大桥桥面铺装层进行品质化提升,延长其桥面系服役寿命,采用高韧超薄沥青磨耗层技术,以高粘高弹聚合物改性沥青(GT-TECH)为胶结料,采用5~8mm和3~6mm辉绿岩碎石、0~5mm辉绿岩石粉砂和矿粉进行高韧超薄沥青混合料(GT-8)的配... 详细信息

为对常德市武陵大桥桥面铺装层进行品质化提升,延长其桥面系服役寿命,采用高韧超薄沥青磨耗层技术,以高粘高弹聚合物改性沥青(GT-TECH)为胶结料,采用5~8mm和3~6mm辉绿岩碎石、0~5mm辉绿岩石粉砂和矿粉进行高韧超薄沥青混合料(GT-8)的配合比设计,并通过路用性能试验及实际工程应用,综合评价其使用性能。现场测试表明,高韧超薄沥青磨耗层的平整度实测值均小于2.0m/km,具有良好的行车舒适性;构造深度实测值均大于0.8mm,摩擦系数实测平均值均大于55BPN,桥面具有良好的抗滑性能。应用实践证明,高韧超薄沥青磨耗层的总体应用效果良好。

关键词：桥面铺装高韧超薄沥青磨耗层高粘高弹改性沥青路用性能

Experimental-mechanistic analysis of pavement base deflections measured with light weight deflectometer

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Journal of Traffic and Transportation Engineering(English Edition) 2023年第2期10卷 320-330页

作者： Yao Yao Shuo Li guangyuan Zhao yi Jiang Shanghai Urban Construction Design and Research Institute(Group)Co.Ltd. Shanghai 200000China Indiana Department of Transportation West LafayetteIN 47906USA Department of Civil and Environmental Engineering University of WaterlooWaterlooON N2L 3G1Canada School of Construction Management Technology Purdue UniversityWest LafayetteIN 47907USA

An extensive experimental-mechanistic study was conducted to reveal the relationship between the light weight deflectometer(LWD)measured deflections and the degree of compaction of pavement base *** laboratory experiments and test pits experiments were performed with different types of pavement base *** modulus based maximum allowable LWD deflections under different structural and compaction conditions were developed for the most commonly used pavement base aggregate in *** maximum allowable deflections are based on the equivalent subgrade modulus and the thickness of the layer to be *** is emphasized that the LWD deflections must be measured as soon as the material is compacted or before the moisture content decreases beyond a specified ***,the maximum allowable deflections are specified in terms of the difference between the actual moisture content and the optimum moisture *** maximum allowable deflection values provide a sound basis for compaction quality control using LWD devices.

关键词： Pavement Light weight deflectometer Compaction Deflection Moisture content Modulus

Cost effectiveness of new roadway lighting systems

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Journal of Traffic and Transportation Engineering(English Edition) 2015年第3期2卷 158-166页

作者： yi Jiang Shuo Li Bowen Guan guangyuan Zhao Department of Building Construction Management Purdue University School of Civil Engineering and Architecture Wuhan Polytechnic University office of Research and Development Indiana Department of Transportation School of Materials Science and Engineering Chang'an University

Appropriate and adequate lighting at select locations on roadways is essential for roadway safety. As the lighting technologies advance, many Wpes of new lighting devices have been developed for roadway lightings. The most promising new lighting technologies for roadway lighting include light emitting diode, induction, plasma, and metal halide lighting systems. A study was conducted to compare the new systems with the conventional high pressure sodium systems that are currently used on the Indiana roadway systems. In this study, the engineering issues, were analyzed such as illuminance, color rendering, power usage, cost effectiveness, and approval procedures for new roadway lighting systems. This paper, however, presents only the study findings related to cost effectiveness of the evaluated roadway lighting systems. Illustrated in this paper are the main features of the roadway lighting systems under evaluations, installations of the new lighting systems, measurements of power consumptions, and life cycle cost analyses of the lighting systems. Through this study, experience and knowledge have been obtained on the installations, power measurements, and cost effectiveness of the new types of the roadway lighting devices. The actual power values of various luminaires were obtained by measuring the electric current with a multi-meter. It was found that the differences between the rated and measured power values could be significant. The results of the life cycle cost analysis indicate that the lower life cycle costs of some of the alternative lighting devices are attributed to their relatively lower electricity usages and longer lamp/emitter replacement cycles.

关键词： Roadway lighting Life cycle cost Luminaire Power consumption

Field evaluation of selected light sources for roadway lighting

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Journal of Traffic and Transportation Engineering(English Edition) 2018年第5期5卷 372-385页

作者： yi Jiang Shuo Li Bowen Guan guangyuan Zhao Dave Boruff Lalit Garg Prakash Patel Department of Building Construction Management Purdue University West Lafayette IN 47907 USA Division of Research and Development Indiana Department of Transportation West Lafayette IN 47906 USA School of Materials Science and Engineering Chang'an University Xi'an 710064 China Indiana Department of Transportation Indianapolis IN 46204 USA

The development of new lighting sources, such as light emitting diode （LED）, induction, and plasma, presented more possible cost effective ways for roadway lighting. A study was therefore conducted for the Indiana Department of Transportation （INDOT} to evaluate the performance and effectiveness of some selected new lighting devices in roadway lighting. This paper describes the field evaluation process and presents the evaluation results. A number of LEDs, plasma and induction luminaires from various manufacturers were selected to replace the existing high pressure sodium （HPS） lamps in conventional and high mast lightings, llluminance values were measured over a period of 12 months on the existing and new light sources. Light performance metrics, including illuminance level and uniformity ratios, were calculated to make quantitative comparisons of the HPS and new types of light devices. Based on the evaluation in terms of lighting performance and life cycle costs, it was concluded that LED luminaires should be utilized in roadway lighting in place of HPS luminaires. The results of this study will be useful to state highway and city street agencies in making decisions on their lighting policies and developing technical specifications for use of the new lighting technologies in roadway and street lightings. The study provides a basis for manufacturers to improve their luminaire design and integration to better fit the needs of roadway and street lightings.

关键词： Roadway lighting Luminaires Illuminance Field tests LEDHPS

Associations of Ambient NO2 with Daily Hospitalization,Hospitalization Expenditure and Length of Hospital Stay of Cause-Specific Respiratory Diseases-Shanxi,China,2017-2019

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China CDC weekly 2022年第35期4卷 779-782,I0002-I0004页

作者： Dashan Zheng Dawei Cao Shiyu Zhang Huiqing Shen yi Liu Qiyong Liu Jimin Sun guangyuan Jiao Jianzhen Wang Xiaoran Yang Xinri Zhang Hualiang Lin School of Public Health Sun Yat-sen UniversityGuangzhou CityGuangdong ProvinceChina Department of Respiration First Hospital of Shanxi Medical UniversityTaiyuan CityShanxi ProvinceChina Key Laboratory of Infectious Disease Prevention and Control Collaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesNational Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijingChina Key Laboratory of Vaccine Prevention and Control of Infectious Disease of Zhejiang ProvinceZhejiang Provincial Center for Disease Control and PreventionHangzhou CityZhejiang ProvinceChina Department of Ideological and Political Education School of MarxismCapital Medical UniversityBeijingChina Department of Standards and Evaluation Beijing Municipal Health Commission Policy Research CenterBeijing Municipal health Commission Information CenterBeijingChina

Summary What is already known about this topic?Numerous epidemiological studies have documented the association between ambient nitrogen dioxide(NO2)and mortality and morbidity of respiratory diseases,however,research on the effect of NO2 on the length of hospital stay(LOS)and hospitalization expenditure is *** is added by this report?This study collected the respiratory hospitalization,hospital expenditure,and LOS for respiratory diseases from 2017-2019 in Shanxi,China,and comprehensively evaluated the association between ambient NO2 exposure and respiratory hospitalization,expenditure,and *** are the implications for public health practice?This study provides evidence on the association between ambient NO2 and respiratory burden,suggesting that continuously reducing the NO2 concentrations could prevent respiratory diseaseassociated hospital admissions and decrease the relative burden in Shanxi Province and other similar regions.

关键词： ambient Shanxi burden

Optimizing local search-based partial MaxS AT solving via initial assignment prediction

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Science China(Information Sciences) 2024年

作者： Chanjuan LIU guangyuan LIU Chuan LUO Shaowei CAI Zhendong LEI Wenjie ZHANG yi CHU Guojing ZHANG School of Computer Science and Technology Dalian University of Technology School of Software Beihang University Institute of Software Chinese Academy of Sciences School of Computer Science Peking University

Partial maximum satisfiability(PMS) is a significant generalization of Boolean satisfiability(SAT) and maximum satisfiability(MaxSAT), by introducing hard clauses and soft clauses. Compared with SAT and MaxSAT, the PMS problem has more real-world applications where both hard and soft constraints are involved. Local search is an effective incomplete method for solving PMS and is useful for important domains where good-quality solutions are desired within reasonable *** local search PMS solvers, the approach for initial assignment generation is crucial because its effectiveness significantly affects practical performance. In this study, we propose a novel initial assignment prediction approach, called InitPMS. When predicting an assignment for PMS, InitPMS considers the specific structure of PMS instances, i.e., distinguishing hard and soft clauses. Our experiments on extensive PMS instances from MaxSAT evaluations(MSEs) 2020 and 2021 show that InitPMS significantly boosts the performance of five state-of-the-art local search PMS solvers, demonstrating its generality. In addition,our results indicate that incorporating InitPMS could improve the performance of one of the best incomplete PMS solvers in MaxSAT Evaluation 2021, indicating that InitPMS might help advance the state of the art in PMS solving.

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Cloning and Characterization of CBL genes in wheat (Triticum aestivum.)

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Cloning and Characterization of CBL genes in wheat (Triticum...