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基于自适应阈值的脉冲激光引信时刻鉴别方法

探测与控制学报 2024年第4期46卷 32-38,57页

作者：程碧瑶张雅茹李雨蔚王小卓付曦瑶唐辉中国兵器工业集团第二一二研究所陕西西安710065 机电动态控制重点实验室陕西西安710065 长春理工大学高功率半导体激光国家重点实验室吉林长春130022

由于门限阈值电压固定,传统脉冲激光引信接收系统的时刻鉴别电路极易产生信号误判而引起虚警或漏警。针对此问题,提出基于自适应阈值的脉冲激光引信回波时刻鉴别方法,并进行电路优化设计。该方法通过将时刻鉴别电路中门限阈值和放大信... 详细信息

由于门限阈值电压固定,传统脉冲激光引信接收系统的时刻鉴别电路极易产生信号误判而引起虚警或漏警。针对此问题,提出基于自适应阈值的脉冲激光引信回波时刻鉴别方法,并进行电路优化设计。该方法通过将时刻鉴别电路中门限阈值和放大信号进行关联,使得门限阈值电压可以根据信号源中直流分量及噪声的变化而自适应调节,可显著降低时刻鉴别误差。LT spice软件仿真结果表明:随着直流分量的增加,门限阈值增加,该优化电路可根据直流分量的变化而自适应调节;随着信噪比的增大,门限阈值自动降低,该优化电路可根据噪声变化而自适应调节。该优化电路可将比较器输入两端的电压差控制在适当的范围,实现对脉冲结果的控制。该自适应阈值时刻鉴别电路结构简单、易于实现,为实现激光引信的高精度测距提供了有效的支持。

关键词：激光引信时刻鉴别电路自适应阈值

Ipsilateral versus bilateral limb-training in promoting the proliferation and differentiation of endogenous neural stem cells following cerebral infarction in rats

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Neural Regeneration Research 2012年第34期7卷 2698-2704页

作者： xiyao Yang Feng Zhu Xiaomei zhang Zhuo Gao Yunpeng Cao Department of Neurology the First Affiliated Hospital of China Medical University Department of Neurology Shenyang Brain Hospital The First People's Hospital of Dandong

We investigated the effects of ipsilateral versus bilateral limb-training on promotion of endogenous neural stem cells in the peripheral infarct zone and the corresponding cerebral region in the unaffected hemisphere of rats with cerebral infarction. Middle cerebral artery occlusion was induced in Wistar rats. The rat forelimb on the unaffected side was either wrapped up with tape to force the use of the paretic forelimb in rats or not braked to allow bilateral forelimbs to participate in training. Daily training consisted of mesh drum training, balance beam training, and stick rolling training for a total of 40 minutes, once per day. Control rats received no training. At 14 days after functional training, rats receiving bilateral limb-training exhibited milder neurological impairment than that in the ipsilateral limb-training group or the control group. The number of nestin/glial fibrillary acidic protein-positive and nestin/microtubule-associated protein 2-positive cells in the peripheral infarct zone and in the corresponding cerebral region in the unaffected hemisphere was significantly higher in rats receiving bilateral limb-training than in rats receiving ipsilateral limb-training. These data suggest that bilateral limb-training can promote the proliferation and differentiation of endogenous neural stem cells in the bilateral hemispheres after cerebral infarction and accelerate the recovery of neurologic function. In addition, bilateral limb-training produces better therapeutic effects than ipsilateral limb-training.

关键词： bilateral rehabilitation training affected limb bilateral limbs peripheral infarct zone unaffectedhemisphere middle cerebral artery occlusion brain neural stem cells proliferation differentiation plasticity neural regeneration

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高速动车组轴箱轴承保持架材料研究

高速铁路新材料 2023年第4期2卷 49-53页

作者：刘凤山孟兆会谢晓陶国安张玺瑶北京隆轩橡塑有限公司北京100072 中国铁道科学研究院集团有限公司金属及化学研究所北京100081

研究了温度、水分、油脂热老化对保持架原材料力学性能的影响,并参照相关标准,研究了原材料性能对于保持架产品机械性能、疲劳性能的影响,优选出性能优良的高速动车组轴箱轴承保持架原材料;并对高速动车组轴箱轴承保持架产品主要性能进... 详细信息

研究了温度、水分、油脂热老化对保持架原材料力学性能的影响,并参照相关标准,研究了原材料性能对于保持架产品机械性能、疲劳性能的影响,优选出性能优良的高速动车组轴箱轴承保持架原材料;并对高速动车组轴箱轴承保持架产品主要性能进行了综合评价,验证了优选材料制造的保持架具有良好的机械性能和抗疲劳性能。

关键词：动车组轴承保持架聚酰胺疲劳

Preparation of Monodispersed Carbon Spheres via Hydrothermal Carbonization of Ascorbic Acid and Their Application in Lithium Ion Batteries

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Chemical Research in Chinese Universities 2018年第4期34卷 628-634页

作者： ZHOU Xuejiao XU Liangyou LIU xiyao zhang Junjun DIAO Hongchao MA Xiaohua School of Advanced Materials and Nanotechnology Xidian University Xi 'an 710071 P. R. China

Hydrothermal carbonization is one of the most appealing strategies to prepare carbon spheres（CSs）. Nevertheless, the precursors of hydrothermal carbonization are limited to several saccharides currently and the obtained CSs are easily interconnected among each other, giving rise to difficulties in further treatment and applications. In this work, ascorbic acid was used as precursor in the hydrothermal procedure and monodispersed CSs could be fa- bricated without any catalysts. In addition, the composites of CSs and chemical reduced graphene oxide（CRG） pos- sessing three dimensional network structures were fabricated, which exhibited excellent electrochemical performance used as anode in lithium ion battery（LIB）. Meanwhile, the effects of size distributions of CSs on the electrochemical performances were evaluated.

关键词： Carbon sphere Graphene Lithitwn ion battery Ascorbic acid

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基于多因素分析的烘丝机智能调控研究

控制工程 2024年第6期31卷 1138-1145页

作者：张风光张思明林敏叶明樵周萍芳蒋鹏冲刘西尧温延湖北中烟工业有限责任公司武汉卷烟厂湖北武汉430040

烘丝过程中影响出口烟丝水分和温度的干扰因素较多,为了保障出口烟丝水分与温度的稳定性,首先基于烘丝过程的历史数据,采用相关性分析方法对影响因子进行筛选。其次,选取出口烟丝水分和出口烟丝温度为目标值,通过对各机器学习模型的对... 详细信息

烘丝过程中影响出口烟丝水分和温度的干扰因素较多,为了保障出口烟丝水分与温度的稳定性,首先基于烘丝过程的历史数据,采用相关性分析方法对影响因子进行筛选。其次,选取出口烟丝水分和出口烟丝温度为目标值,通过对各机器学习模型的对比分析选取了能够快速建模与预测的极限学习机(extreme learning machine,ELM)作为建模方法,以通过模型求解运算,得出预测值。最后,采用模拟退火(simulated annealing,SA)算法,实时优化热风风速和排潮风门开度的设定值,实现对出口烟丝水分和温度的预测和控制。实验结果表明,极限学习机模型的预测效果良好,预测当前出口水分的均方根误差为0.015,出口温度的均方根误差为0.638,误差较小,保障了烘丝机智能调控方法的调控精度。

关键词：极限学习机相关性分析烘丝机模型预测实时优化

乙型肝炎病毒DNA载量对晚期肝细胞癌系统治疗安全性及预后的影响

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中华医学杂志 2024年第14期104卷 1160-1167页

作者：郑杏容彭建新宋欣刘波钟崇陈希瑶张博翔彭亮朱康顺谢婵中山大学附属第三医院感染性疾病科，广州510630 广州中医药大学第二附属医院肝胆外科，广州510120 中山大学附属第三医院普外科，广州510630 广州中医药大学第一附属医院肝胆外科，广州510405 广州医科大学附属第二医院微创介入科介入放射学实验室，广州510260

目的观察乙型肝炎(乙肝)病毒(HBV)阳性对接受系统治疗的晚期肝细胞癌(肝癌)患者发生肝损害、HBV再激活(HBVr)及HBVr对系统治疗预后的影响。方法回顾性收集2018年7月至2020年12月中山大学附属第三医院等4家医院403例乙肝相关肝癌患者的... 详细信息

目的观察乙型肝炎(乙肝)病毒(HBV)阳性对接受系统治疗的晚期肝细胞癌(肝癌)患者发生肝损害、HBV再激活(HBVr)及HBVr对系统治疗预后的影响。方法回顾性收集2018年7月至2020年12月中山大学附属第三医院等4家医院403例乙肝相关肝癌患者的临床资料,分析系统治疗期间肝损害及HBVr发生率,并分析HBVr对生存预后的影响。结果共纳入403例患者,359例(89.1%)为男性,年龄(51.5±12.1)岁。进行倾向性评分匹配(PSM)前,高HBV-DNA(基线HBV-DNA>1000 U/ml,n=147)组与低HBV-DNA(基线HBV DNA≤1000 U/ml,n=256)组相比,肝硬化、TNM及巴塞罗那分期(BCLC)晚期患者比例较高(P0.05)。对169例有生存数据的患者进行生存分析,发现高HBV-DNA组和低HBV-DNA组的中位总生存期(OS)分别为11.49个月(95%CI:7.77~12.89)和16.65个月(95%CI:10.54~21.99,P=0.008),中位无进展生存期(PFS)分别为7.41个月(95%CI:5.06~8.67)和10.55个月(95%CI:6.72~13.54,P=0.038),差异均有统计学意义,但有无HBVr、有无肝损害的患者OS和PFS差异均无统计学意义(均P>0.05)。结论系统治疗前HBV-DNA>1000 U/ml并不增加乙肝相关肝癌患者系统治疗时肝损害或HBVr的风险,该类患者可以安全地接受系统治疗。

关键词：免疫治疗肝细胞癌慢性乙型病毒性肝炎安全性

Evaluation on Fabrication and Properties of Composite Polyurethane Coatings with Wollastonite Partially Substituting for Rutile Titanium Dioxide

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Transactions of Tianjin University 2019年第3期25卷 293-300页

作者： Xiaojing Wang Wei zhang Yangyang Yan Jing Wang xiyao Wang School of Chemical Engineering and Technology Tianjin University School of Environmental Science and Engineering Tianjin University

This study aims to prepare a composite polyurethane coating through a facile synthesis process. Titanium dioxide, which is a component of the prepared hydroxyl acrylic resin polyurethane varnish, was partially substituted by wollastonite, and an optimal substitution ratio was obtained. Analyses based on scanning electron microscope, powder X-ray diffraction, and Raman scattering measurements demonstrated that the addition of wollastonite caused nearly no change in the basic structure of the coating. Coating with a substitution ratio of 25% showed high thermal stability, good cover effect, considerable moisture-proof and water resistance ability, great acidic and basic resistance, and improved performance and hardness in performance tests. Furthermore, the production cost was reduced significantly at this substitution ratio.

关键词： Polyurethane coating Wollastonite Rutile titanium dioxide Hydroxyl acrylic acid Thermal stability

Environmental impact factors and mercury speciation in the sediment along Fujian and eastern Guangdong coasts

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Acta Oceanologica Sinica 2013年第2期32卷 76-80页

作者： zhang Yuanbiao HUO Yunlong LIU xiyao KUANG Weiming YUAN Dongxing JI Weidong State Key Laboratory of Marine Environmental Science Xiamen University Third Institute of Oceanography State Oceanic Administration

Concentrations of total mercury （THg） and methyl mercury （MeHg） were determined for 32 surface sed- iments collected along the coastal line of Fujian Province and eastern Guangdong Province. The spatial distributions of THg and MeHg and their environmental impact factors were investigated. The average con- centrations of THg and MeHg in the sediments were 31.5 ng/g and 0.096 ng/g, respectively. Both sediment THg and MeHg concentrations showed relatively high value in the Minjiang Estuary and the coastal areas of Quanzhou and Putian. The concentrations overall decreased as the distance to the shoreline increased. The correlations among environmental impact factors and THg, MeHg were analyzed. The sediment THg concentration was highly correlated to the concentrations of organic matter, copper, total nitrogen （TN） and total phosphorus （TP）, and significantly correlated to pH value of the bottom seawater and concentration of sediment sulfide. The sediment MeHg concentration was highly correlated to the concentrations of organic matter and copper, and significant correlated to the concentrations of sulfide, TN, TP and pH value of the bottom seawater.

关键词： mercury methyl mercury coastal area sediment speciation

The levels of microbial diversity in dif ferent water layers of saline Chagan Lake,China

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Journal of Oceanology and Limnology 2020年第2期38卷 395-407页

作者： zhang Lei CAI Yanan JIANG Miao DAI Jing GUO xiyao LI Wei LI Yuehong College of Animal Science and Technology Jilin Agriculture UniversityChangchun 130118China Biomarker Technologies Co.Ltd. Beijing 100000China Department of Clinical Laboratory China-Japan Union HospitalChangchun 130000China

Saline lakes represent a particularly interesting aquatic environment for harboring high microbial ***,the microbial diversity in different states and locations of saline lake is often *** studied for the first time the diversity and relative composition of the microbial communities in the Chagan Lake,NE China,and investigated the dif ferences in microbial species and physical and chemical factors in different geographical localities of the *** extracting the total DNA of the sample,we tested the library with the established library,sequenced the qualified library with Illumina HiSeq 2500,and studied the bacterial diversity by 16 S rRNA targeted metagenomics *** reveal that the highest microbial abundance in Chagan Lake at genus level was Proteobacterium followed by Actinomycetes and *** addition,we compared the microbial composition within the lake using alpha-and beta-diversity indices,showing that both diversity and evenness were the highest in the middle of the lake and lowest in the west of lake areas,and in the upper,middle,and lower depth of water columns,the low water column had the highest species number in the whole water environment,but the dif ference was not *** believe that physicochemical factors contribute to the formation of microbial community composition and *** aquaculture industry,it is impossible apply horticulture for making full use of the spatial dif ferences in the microbial composition of the ***,combining cultured aquatic animal with the most suitable microbial species is a good way to boost the breeding ef fect for greater economic value.

关键词： saline lake aquatic environment microbial diversity physical and chemical factors Chagan Lake