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Multi-Traffic Targets Tracking Based on an Improved Structural Sparse Representation with Spatial-Temporal Constraint

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Chinese Journal of Electronics 2022年第2期31卷 266-276页

作者： YANG Honghong shang Junchao LI Jingjing ZHANG Yumei WU Xiaojun Key Laboratory of Modern Teaching Technology Ministry of EducationShaanxi Normal University School of Computer Science Shaanxi Normal University School of Journalism and Communication Shaanxi Normal University

Vehicles or pedestrians tracking is an important task in intelligent transportation system. In this paper, we propose an online multi-object tracking for intelligent traffic platform that employs improved sparse representation and structural constraint. We first build the spatial-temporal constraint via the geometric relations and appearance of tracked objects, then we construct a robust appearance model by incorporating the discriminative sparse representation with weight constraint and local sparse appearance with occlusion analysis. Finally, we complete data association by using maximum a posteriori in a Bayesian framework in the pursuit for the optimal detection estimation. Experimental results in two challenging vehicle tracking benchmark datasets show that the proposed method has a good tracking performance.

关键词： Intelligent vehicles Multi-traffic object tracking Sparse representation Spatial-temporal constraint

Mechanism and Method of Testing Fracture Toughness and Impact Absorbed Energy of Ductile Metals by Spherical Indentation Tests

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Chinese Journal of Mechanical Engineering 2023年第5期36卷 156-173页

作者： Jianxun Li Tairui Zhang shang Wang Jirui Cheng Weiqiang Wang Key Laboratory of High-efciency and Clean Mechanical Manufacture(Ministry of Education) National Demonstration Center for Experimental Mechanical Engineering Education(Shandong University)School of Mechanical EngineeringShandong UniversityJinan 250061China School of Mechanical Engineering Southeast UniversityNanjing 211189China College of Electromechanical Engineering Qingdao University of Science and TechnologyQingdao 266061China

To address the problem of conventional approaches for mechanical property determination requiring destructive sampling, which may be unsuitable for in-service structures, the authors proposed a method for determining the quasi-static fracture toughness and impact absorbed energy of ductile metals from spherical indentation tests (SITs). The stress status and damage mechanism of SIT, mode I fracture, Charpy impact tests, and related tests were frst investigated through fnite element (FE) calculations and scanning electron microscopy (SEM) observations, respectively. It was found that the damage mechanism of SITs is diferent from that of mode I fractures, while mode I fractures and Charpy impact tests share the same damage mechanism. Considering the diference between SIT and mode I fractures, uniaxial tension and pure shear were introduced to correlate SIT with mode I fractures. Based on this, the widely used critical indentation energy (CIE) model for fracture toughness determination using SITs was modifed. The quasi-static fracture toughness determined from the modifed CIE model was used to evaluate the impact absorbed energy using the dynamic fracture toughness and energy for crack initiation. The efectiveness of the newly proposed method was verifed through experiments on four types of steels: q345R, SA508-3, 18MnMoNbR, and S30408.

关键词： Spherical indentation tests Fracture toughness CIE model Impact absorbed energy

A pseudo-random sequence generation scheme based on RNS and permutation polynomials

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Science China(Information Sciences) 2018年第8期61卷 183-194页

作者： shang MA Jianfeng LIU Zeguo YANG Yan ZHANG Jianhao HU National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of China

Long period pseudo-random sequence plays an important role in modern information processing systems. Base on residue number system(RNS) and permutation polynomials over finite fields, a pseudorandom sequence generation scheme is proposed in this paper. It extends several short period random sequences to a long period pseudo-random sequence by using RNS. The short period random sequences are generated parallel by the iterations of permutation polynomials over finite fields. Due to the small dynamic range of each iterative calculation, the bit width in hardware implementation is reduced. As a result, we can use full look-up table(LUT) architecture to achieve high-speed sequence output. The methods to find proper permutation polynomials to generate long period sequences and the optimization algorithm of Chinese remainder theorem(CRT) mapping are also proposed in this paper. The period of generated pseudorandom sequence can exceed 2100 easily based on common used field programmable gate array(FPGA) ***, this scheme has extensive freedom in choosing permutation polynomials. For example, 10905 permutation polynomials meet the long period requirement over the finite field Fq with q ■ 1(mod 3) and q 503. The hardware implementation architecture is simple and multiplier free. Using Xilinx XC7020 FPGA chip, we implement a sequence generator with the period over 250, which only costs 20 18 kb-BRAMs(block RAM) and a small amount of logics. And the speed can reach 449.236 Mbps. The National Institute of Standards and Technology(NIST) test results show that the sequence has good random properties.

关键词： pseudo-random sequence residue number system(RNS) permutation polynomial high speed long period field programmable gate array(FPGA)

不同外源激素处理对弗吉尼亚栎种子发芽的影响

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安徽农业科学 2024年第12期52卷 113-116,176页

作者：马尚崔蓝芳王富河信阳市平桥区林业局河南信阳464100 信阳农林学院河南信阳464100

为提高弗吉尼亚栎种子的发芽率,以弗吉尼亚栎种子为材料,选用不同浓度的吲哚乙酸(IAA)、萘乙酸(NAA)外源激素分别浸种1、3 h,以清水浸种1、3 h为对照,在20℃恒温下观测种子的发芽指标。结果表明:100 mg/L NAA浸种1 h发芽率为66.70%,100... 详细信息

为提高弗吉尼亚栎种子的发芽率,以弗吉尼亚栎种子为材料,选用不同浓度的吲哚乙酸(IAA)、萘乙酸(NAA)外源激素分别浸种1、3 h,以清水浸种1、3 h为对照,在20℃恒温下观测种子的发芽指标。结果表明:100 mg/L NAA浸种1 h发芽率为66.70%,100、200 mg/L IAA浸种3 h和150 mg/L浸种1 h IAA发芽势均为53.30%;100 mg/L IAA浸种3 h的发芽指数为16.38;100 mg/L IAA浸种3 h的胚根生长为3.80 cm,优于对照及其他处理。

关键词：外源激素北美栎树弗吉尼亚栎发芽率

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基于对象模型的煤矿数据采集融合共享系统

工矿自动化 2024年第1期50卷 17-24,34页

作者：尚伟栋王海力张晓霞王浩徐华龙山西天地王坡煤业有限公司山西晋城048021 煤炭科学研究总院有限公司矿山大数据研究院北京100013 煤炭科学技术研究院有限公司北京100013

针对目前煤矿数据采集、融合与共享存在的设备属性缺乏标准化且语义不统一、数据采集规约无法跨操作系统、数据访问实时性差、数据共享效率低等问题,设计了一种基于对象模型的煤矿数据采集融合共享系统。在基于位号的煤矿数据编码标准... 详细信息

针对目前煤矿数据采集、融合与共享存在的设备属性缺乏标准化且语义不统一、数据采集规约无法跨操作系统、数据访问实时性差、数据共享效率低等问题,设计了一种基于对象模型的煤矿数据采集融合共享系统。在基于位号的煤矿数据编码标准的基础上设计设备对象模型,克服了设备属性缺少标准化和设备属性语义不统一的问题;采用工业规约采集、Restful API问答式采集和文件数据采集等数据接入方式,可支持国产化操作系统,提供了方便的报文监视工具,能够准确判断通信异常原因;通过设备对象模型映射实现数据融合,引入数据治理机制确保数据的准确性和一致性,以对象模型的形式存储数据来节省存储空间、提高存储效率;将所有设备对象数据存储到一张表中,对象化的数据共享接口可简化成实时数据共享接口和历史数据共享接口,减少了冗余接口,从而降低了数据访问次数。应用结果表明,该系统在对设备数据标准化后降低了数据使用过程中语义解析的难度,同时提高了数据的计算、存储和访问性能,为大数据分析提供了保障。

关键词：数据采集数据融合数据共享对象模型数据编码数据治理数据存储

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Forecast for cosmological parameter estimation with gravitational-wave standard sirens from the LISA-Taiji network

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Science China(Physics,Mechanics & Astronomy) 2022年第1期65卷 1-13页

作者： Ling-Feng Wang shang-Jie Jin Jing-Fei Zhang Xin Zhang Department of Physics College of SciencesNortheastern UniversityShenyang 110819China MOE Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern UniversityShenyang 110819China

LISA and Taiji are expected to form a space-based gravitational-wave(GW)detection network in the *** this work,we make a forecast for the cosmological parameter estimation with the standard siren observation from the LISA-Taiji *** simulate the standard siren data based on a scenario with configuration angle of 40°between LISA and *** models for the population of massive black hole binary(MBHB),i.e.,popⅢ,q3d,and q3nod,are considered to predict the events of MBHB *** find that,based on the LISA-Taiji network,the number of electromagnetic(EM)counterparts detected is almost doubled compared with the case of single Taiji ***,the LISA-Taiji network’s standard siren observation could provide much tighter constraints on cosmological *** example,solely using the standard sirens from the LISA-Taiji network,the constraint precision of H;could reach 1.3%.Moreover,combined with the CMB data,the GW-EM observation based on the LISA-Taiji network could also tightly constrain the equation of state of dark energy,e.g.,the constraint precision of w reaches about 4%,which is comparable with the result of CMB+BAO+*** is concluded that the GW standard sirens from the LISA-Taiji network will become a useful cosmological probe in understanding the nature of dark energy in the future.

关键词： LISA-Taiji network gravitational-wave standard siren cosmological parameter estimation massive black hole binary electromagnetic counterpart

基于UHPLC-q-TOF/MS技术分析肿节风总黄酮提取物促进巨核细胞分化的效应成分

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中药新药与临床药理 2024年第1期35卷 56-64页

作者：张钟康卢晓南卢震胡佳刘慧珍卢婷尚广彬江西中医药大学中医基础理论分化发展中心江西南昌330004 江西省中医病因生物学重点实验室江西南昌330004 江西中医药大学中医学院江西南昌330004 江西中医药大学临床医学院江西南昌330004

目的筛选肿节风总黄酮提取物促进巨核细胞分化的效应成分。方法(1)以人巨核细胞白血病细胞(Dami)与人骨髓基质细胞(HS-5)共培养的方式建立巨核细胞分化障碍模型作为评价体系,实验分组:Dami组(Dami)、对照组(Dami+HS-5)、PMA组[Dami+HS-5... 详细信息

目的筛选肿节风总黄酮提取物促进巨核细胞分化的效应成分。方法(1)以人巨核细胞白血病细胞(Dami)与人骨髓基质细胞(HS-5)共培养的方式建立巨核细胞分化障碍模型作为评价体系,实验分组:Dami组(Dami)、对照组(Dami+HS-5)、PMA组[Dami+HS-5+5 ng·mL-1佛波醇12-十四酸酯13-乙酸酯(PMA)]、模型组[Dami+HS-5+1%兔抗大鼠血小板血清(APS)+5 ng·mL-1PMA],培养48 h。采用流式细胞术检测巨核细胞分化成熟表面标记分子CD41a、CD61的表达情况。(2)将49只SD雄性大鼠随机分为空白血浆组、15 min组、30 min组、60 min组、90 min组、120 min组、240 min组,每组7只。各给药组大鼠灌胃肿节风总黄酮提取物1.26 g·kg^(-1),在6个设定时间点(15、30、60、90、120、240 min)采血制备肿节风总黄酮提取物经时含药血浆。(3)采用超高效液相色谱-四极杆串联飞行时间质谱法(UHPLC-q-TOF/MS)对肿节风总黄酮提取物经时含药血浆进行分析,以峰面积构建肿节风总黄酮提取物经时含药血浆中的化学成分随时间变化量矩阵(X矩阵)。将所采集的6个不同时间点的肿节风总黄酮经时含药血浆对巨核细胞分化成熟障碍模型进行干预,采用流式细胞术检测细胞表面分子CD41a、CD61的表达水平,构建肿节风总黄酮提取物经时含药血浆效应矩阵(Y矩阵)。(4)将X矩阵和Y矩阵数据标准化处理后,采用偏最小二乘法(Partial least squares,PLS)计算分析量效关系,以变量重要性投影(Variable importance for projection,VIP)>1为阈值,筛选与细胞表面分子CD41a、CD61变化相关的效应成分,并进行化学成分鉴定,作为肿节风总黄酮提取物中促进巨核细胞分化的潜在效应成分,最后回归评价体系验证其药效。结果(1)与Dami组比较,对照组Dami细胞表面的CD41a表达水平明显升高(P1的潜在效应成分,并选取540.3638@12.25与559.2991@11.53两个成分进行药效学验证。559.2991@11.53被鉴定为胡萝卜苷(Daucosterol,Dau),540.3638@12.25被鉴定为迷迭香酸-4-O-β-D-葡萄糖(Rosmarinic acid 4-O-β-Dglucoside,Ros)。Ros、Dau分别干预巨核细胞分化成熟障碍模型后,与模型组比较,Ros及Dau低、中、高剂量组(40、60、80μg·mL-1)的Dami细胞表面的CD41a、CD61表达水平均显著升高(P<0.05,P<0.01)。结论Ros、Dau可能是肿节风总黄酮提取物促进巨核细胞分化的效应成分。

关键词：肿节风总黄酮提取物免疫性血小板减少症巨核细胞分化障碍模型人巨核白血病细胞人骨髓基质细胞超高效液相色谱-四极杆串联飞行时间质谱法偏最小二乘法胡萝卜苷迷迭香酸-4-O-β-D-葡萄糖

基于UPLC-q-TOF/MS鉴定健脾益肠散大鼠体内外源物成分

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中草药 2024年第6期55卷 1908-1924页

作者：孔心雨李璐商晶刘文君钱梦雨王振中肖伟南京中医药大学江苏南京210000 江苏康缘药业股份有限公司江苏连云港222001 中药过程控制与智能制造技术全国重点实验室江苏连云港222001

目的基于UPLC-q-TOF/MS技术研究健脾益肠散在正常大鼠体内的原型成分和代谢产物,归纳总结不同类型化合物的体内代谢规律。方法采用Agilent ZORBAX Eclipse Plus C18(100 mm×2.1 mm,1.8μm)色谱柱,流动相为甲醇(A)-0.1%甲酸水(B),梯度洗... 详细信息

目的基于UPLC-q-TOF/MS技术研究健脾益肠散在正常大鼠体内的原型成分和代谢产物,归纳总结不同类型化合物的体内代谢规律。方法采用Agilent ZORBAX Eclipse Plus C18(100 mm×2.1 mm,1.8μm)色谱柱,流动相为甲醇(A)-0.1%甲酸水(B),梯度洗脱,体积流量0.4 mL/min,柱温30℃,电喷雾离子源(ESI),在正、负离子模式下对色谱流出物进行质谱检测。结果从大鼠血浆、尿液、粪便中鉴定出34个原型成分、79个代谢成分,主要代谢途径包括氧化、还原、甲基化、葡糖醛酸结合、硫酸结合等。结论对健脾益肠散在大鼠体内的外源物成分进行快速有效的定性,为揭示其功效成分的作用机制提供物质基础。

关键词：健脾益肠散 UPLC-q-TOF/MS 原型成分代谢产物补骨脂素

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中医药干预铁死亡治疗炎症性肠病的研究进展

中国实验方剂学杂志 2024年第11期30卷 245-254页

作者：商铭溶赵亚男张旭阳崔惠方赵义静刘明赵德杰山东中医药大学济南250014 山东中医药大学附属医院济南250014

炎症性肠病(IBD)主要包括溃疡性结肠炎(UC)和克罗恩病(CD),是一种常见的消化道慢性炎症性疾病,发病率逐年攀升,因其治疗周期长,治疗难度大,迁延难愈,费用高昂,备受全球关注。探索安全有效持久的治疗方案已成为全球亟待解决的问题。IBD... 详细信息

炎症性肠病(IBD)主要包括溃疡性结肠炎(UC)和克罗恩病(CD),是一种常见的消化道慢性炎症性疾病,发病率逐年攀升,因其治疗周期长,治疗难度大,迁延难愈,费用高昂,备受全球关注。探索安全有效持久的治疗方案已成为全球亟待解决的问题。IBD病机复杂,包括肠黏膜损伤、内环境紊乱、炎症反应等,近年研究发现铁死亡也是IBD的重要致病因素之一。铁死亡作为一种新的非凋亡性细胞死亡方式,主要特点表现为铁依赖性、脂质过氧化和氧化还原系统失衡,有研究表明,抑制肠上皮细胞铁死亡可以起到肠黏膜保护作用,靶向干预铁死亡或许是治疗IBD的新方向。IBD以药物治疗为主,包括皮质类固醇、氨基水杨酸盐、生物制剂和免疫调节剂等,但是易耐药、不良反应较多,而中医药具有价格低廉、耐药性低、不良反应少等独特的优势,在治疗IBD方面积累了丰富的经验。有学者证实中医药可以抑制铁死亡的发生,最新研究表明中医药一方面可以抑制肠道细胞铁依赖性脂质过氧化,另一方面可以提高肠道黏膜抗氧化、抗炎能力,从而起到治疗IBD的作用,越来越多的研究表明中医药或许通过干预铁死亡治疗IBD。该文通过探讨中医药干预铁死与中医药治疗炎症性肠病的相关性,讨论铁死亡在IBD中的可能作用机制,以期为IBD的诊疗提供依据。

关键词：炎症性肠病溃疡性结肠炎克罗恩病铁死亡中医药研究进展