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Chinese Journal of Aeronautics 2021年第4期34卷 56-66页

作者： Jie ZHANG Zhiyu SHI lirong li State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China Shanghai Aircraft Customer Service Co. Ltd.Shanghai 200241China

In this paper,a time–frequency algorithm based on adaptive chirplet transform for parameter modeling and identification of linear Time-Varying(LTV)systems under random excitation is *** is assumed that the solution of responses of LTV structures is expressed as the sum of multicomponent linear Frequency Modulated(LFM)signals in a *** the measured acceleration response is used to perform the adaptive chirplet transform,in which an integral algorithm is employed to reconstruct the velocity and displacement *** vibration differential equation with time-varying coefficients is transformed into a simple linear ***,for systems under random excitation,the input–output relation based on correlation function is also derived to estimate the parameters including physicals parameters and instantaneous modal *** full procedure of the method is presented and validated by using simulated *** results show that the presented method is accurate and robust for various LTV systems under random excitation.

关键词： Acceleration response Chirplet transform LTV systems Random excitation System parameter identification

Characteristics of air pollution by polychlorinated dibenzo-p-dioxins and dibenzofurans in the typical industrial areas of Tangshan City,China

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Journal of Environmental Sciences 2011年第2期23卷 228-235页

作者： Zhiyuan Ren Bing Zhang Pu Lu Cheng li lirong Gao Minghui Zheng Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China.

The ambient air in vicinity of different industrial sources for PCDD/PCDFs was sampled by TSP/PM10 active samplers and passive PUF disk samplers in Tangshan City, a metropolis containing clusters of various industrial plants. The TEQ concentrations of PCDD/PCDFs ranged from 44.2 to 394.1 fg I-TEQ/m^3 with an average of 169.9 fg I-TEQ]m^3. 2,3,4,7,8-PeCDF was the dominant contributor to ∑TEQ, contributing 41% （12% to 55%）, while 1,2,3,4,6,7,8-HpCDE OCDD and OCDF were the major congeners for the total concentrations. The ratios of ∑PCDF/∑PCDD reached 2.54 on average, suggesting that de novo synthesis in thermal processes played an important role to the airborne pollution of PCDD/PCDFs. The similarities congener profiles indicated that TSP and PM10 active sampling methods are comparable for the determination of the PCDD/PCDFs in ambient air, and the ratios of concentrations determined by the two methods suggested that the PCDD/PCDFs tended to stay in fine particles. It was found that 2,3,7,8-TCDF and OCDD were the dominating congeners in the passive PUF disks samples. Through principal components analysis, the coke industry was suggested to be a relatively high potential emission source for PCDD/PCDFs in the ambient air of Tangshan, which was possibly formed by de novo synthesis mechanism. In this study, the atmospheric impacts to the environment from different industrial sources could be ranked as follows （from high to low）： coking, iron sintering, steel making, power generation and chlorinate alkali chemical production industries.

关键词： ambient air dioxins inhalable particles total suspended particles metropolis

New approach to paricalcitol synthesis

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Chinese Science Bulletin 2012年第14期57卷 1616-1619页

作者： li liQi YUE lirong XIE ZhiXiang li Ying State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 China

Paricalcitol,an analog of vitamin D,is used as a drug for the prevention and treatment of secondary *** this paper,a new strategy for the synthesis of paricalcitol is *** approach includes three main improvements:one-pot regioselective ozonization cleavage of the side-chain and methylene at C-19,free-radical reduction removal of the OH group formed at C-19,and side-chain assembly using a Wittig *** are all new strategies for the synthesis of 19-nor-vitamin D2 compounds.

关键词：醇合成维生素D2 清除自由基反应选择性甲状旁腺继发性亚甲基化合物

Stability analysis of longwall top-coal caving face in extra-thick coal seams based on an innovative numerical hydraulic support model

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International Journal of Mining Science and Technology 2024年第4期34卷 491-505页

作者： Jun Guo Wenbo Huang Guorui Feng Jinwen Bai lirong li Zi Wang Luyang Yu Xiaoze Wen Jie Zhang Wenming Feng College of Mining Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Shanxi Province for Mine Rock Strata Control and Disaster Prevention Taiyuan University of TechnologyTaiyuan 030024China Shanxi Coking Coal Group Co. Ltd.Taiyuan 030024China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan 030024China

The relationship between support and surrounding rock is of great significance to the control of surrounding rock in mining *** view of the fact that most of the existing numerical simulation methods construct virtual elements and stress servo control to approximately replace the hydraulic support problem,this paper establishes a new numerical model of hydraulic support with the same working characteristics as the actual hydraulic support by integrating numerical simulation software Rhino,Griddle and FLAC3D,which can realize the simulation of different working *** on this model,the influence mechanism of the supporting strength of hydraulic support on surrounding rock stress regulation and coal stability in front of the top coal caving face in extra thick coal seam were ***,under different support intensity,the abutment pressure of the bearing coal and the coal in front of it presents the “three-stage”evolution *** influence range of support intensity is 15%–30%.Secondly,1.5 MPa is the upper limit of impact that the support strength can have on the front coal failure ***,within a displacement range of 2.76 m from the coal wall,a support strength of1.5 MPa provides optimal control of the horizontal displacement of the coal.

关键词： Extremely thick coal seam Fully mechanized top coal caving Support strength Support-surrounding rock interaction

Combination of anti-PD-1 antibody with P-GEMOX as apotentially effective immunochemotherapy for advancednatural killer/T cell lymphoma

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Signal Transduction and Targeted Therapy 2021年第1期6卷 184-192页

作者： Jun Cai Panpan liu Huiqiang Huang Yajun li Shuyun Ma Hui Zhou Xiaopeng Tian Yuchen Zhang Yan Gao Yi Xia Xuanye Zhang Hang Yang lirong li Qingqing Cai State Key Laboratory of Oncology in South China Collaborative Innovation Center of Cancer MedicineSun Yat-sen University Cancer CenterGuangzhou 510060P.R.China Department of Medical Oncology Sun Yat-sen University Cancer CenterGuangzhou 510060P.R.China Department of Lymphoma and Hematology Hunan Cancer HospitalChangsha 410013P.R.China Department of Lymphoma and Hematology The Affiliated Cancer Hospital of Xiangya School of MedicineCentral South UniversityChangsha 410013P.R.China

Advanced natural killer/T cell lymphoma(NKTL)has demonstrated poor prognosis with currently available ***,we report the efficacy of anti-programmed death 1(PD-1)antibody with the P-GEMOX(pegaspargase,gemcitabine,and oxaliplatin)regimen in advanced *** patients underwent six 21-day cycles of anti-PD-1 antibody(day 1),pegaspargase 2000 U/m^(2)(day 1),gemcitabine 1 g/m^(2)(days 1 and 8)and oxaliplatin 130 mg/m^(2)(day 1),followed by anti-PD-1 antibody maintenance every 3 *** death-ligand 1(PD-L1)expression and genetic alterations were determined in paraffin-embedded pretreatment tissue samples using immunohistochemistry and next-generation sequencing(NGS)*** were assessed using ^(18)F-fluorodeoxyglucose positron emission tomography(^(18)FDG-PET)and computed tomography or magnetic resonance *** patients exhibited significant responses,comprising of seven complete remissions and one partial remission(overall response rate:88.9%).After a median follow-up of 10.6 months,6/9 patients(66.7%)remained in complete *** most common grade 3/4 adverse events were anemia(33.3%),neutropenia(33.3%),and thrombocytopenia(33.3%);all of which were manageable and *** produced a high response rate in patients with positive PD-L1 expression(5/6,83.3%).NGS analysis suggested that STAT3/JAK3/PD-L1 alterations and ARID1A mutation were associated with immunochemotherapy *** in DDX3X and alteration in epigenetic modifiers of KMT2D,TET2,and BCORL1 might indicate a poor response to *** conclusion,the anti-PD-1 antibody plus P-GEMOX regimen demonstrated promising efficacy in advanced ***-L1 expression combined with specific genetic alterations could be used as potential biomarkers to predict therapeutic responses to immunochemotherapy.

关键词： alterations killer lymphoma

Study on CPAs＇ Audit Activities from System Perspective

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Journal of Modern Accounting and Auditing 2005年第5期1卷 66-71页

作者： lirong Han li Zheng Jilin University

This paper studies the nature of CPAs＇ audit activities based on neo-institutional economics. CPA auditing is not only a kind of technical activity serving for particular parties, but also systems arrangement for coordinate interests conflict in the capital market. The common belief in the elimination and prevention of fraud is the foundation of CPA audit system. Professional auditors and audit organizations possess skills and positions matching the stock market. The incentive of audit fees and the binding force of audit liabilities both guarantee the self-implementation of audit system. Audit reports signal the fairness of accounting information in simplified forms. CPA audit system also has inherent contradictions. The CPA audit activities should be viewed from a system perspective in order that ideas for the perfection of audit activities can be raised from system construction perspective.

关键词： system CPA auditing monitoring mechanism

基于“岗课赛证”融通的实践教学改革研究——以临床实践技能课程为例

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卫生职业教育 2025年第1期43卷 34-38页

作者：许晓敏李莉蓉杨淑丽马玲丁奕栋苏州卫生职业技术学院江苏苏州215009

目的在“岗课赛证”综合育人模式下,探索临床实践技能课程教学改革路径与实践效果。方法选取2021级临床医学专业5、6班(对照组)和2022级临床医学专业5、6班(实验组)学生为研究对象,分别采用传统教学法和基于“岗课赛证”融通的“校院一... 详细信息

目的在“岗课赛证”综合育人模式下,探索临床实践技能课程教学改革路径与实践效果。方法选取2021级临床医学专业5、6班(对照组)和2022级临床医学专业5、6班(实验组)学生为研究对象,分别采用传统教学法和基于“岗课赛证”融通的“校院一体、四场联动”教学模式。课程结束后,比较两组课程考核成绩和教学满意度。结果实验组过程性考核优秀率(27.18%)显著高于对照组(14.95%),终结性考核中病史采集与病例分析、心肺听诊、体格检查、基本操作成绩以及总成绩均高于对照组,教学满意度也高于对照组(均P<0.05)。结论基于“岗课赛证”融通的“校院一体、四场联动”教学模式应用于临床实践技能课程,有助于提高学生学习积极性、参与度及教学满意度,提升教学效果。

关键词：岗课赛证实践教学临床实践技能

Determination of bioactivity of culture filtrates of the pathogen causing black spots on the Citrus maxima

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Determination of bioactivity of culture filtrates of the pat...

中国植物病理学会第十一届全国会员代表大会暨2018年学术年会

作者：卢松茂 li lirong Lu Guodong lin Xiuxiang Fujian Institute of Tropic Crops Zhangzhou Meteorological Experiment Station of Tropic Crops Key Laboratory of Biopesticide and Chemical Biology Ministry of EducationFujian Agriculture and Forestry University

[Objective]Phyllosticta citriasiana,the causal agent of Pomelos Black Spot,affects pomelos plants throughout subtropical climates in East Asia,causing a reduction in both fruit quantity and ***,PBS is a major constraints in the production of high quality and wholesome pomelo *** investigations showed that some bioactivity compounds including tauranin,PMtoxins B and C,phyllosinol,phyllostine,phycarone,brefeldin A,cholesterol and elsinochrome A-C had been isolated from some fungal strains of the genus ***,*** had been reported that its crude extracts could inhibit the growth of Escherichia coli,Bacillus cereus,and Pseudomonas aeruginosa,but little is documented about the bioactivities of the cultural filtrates of *** on the host(Citrus maxima) *** this study,the growth morphology and growth rate of *** Pch-1 strain cultured in the different liquid media and the bioactivities of culture filtrates of Pch-1 strain on the wounded leaves of Citrus maxima *** were determined,to preliminarily understand the mechanism of Pch-1 strain infection host leaves and to help further isolation and identification phytotoxic components of Pch-1 strain.[Method]Initially,Pch-1 strain was cultured on the potato dextrose agar(PDA) and cultivated at 25℃ for 2 *** pieces of mycelial disks(5 mm) cut from margin of colony of Pch-1 strain,were kept in a flask with liquid media(100 mL),such as oat liquid medium(OLM),potatoes dextrose liquid medium(PDLM),potatoes sugar liquid medium(PSLM),potatoes sugar potassium phosphate dibasic liquid medium(PSP),improved potatoes dextrose liquid medium(IPDLM),Richard liquid medium(RLM) and Czapek-dox liquid medium(CLM)) with three replications,*** flasks were incubated on an orbital incubator at 120 r/min at 25℃ for 7 days,to investigate the mycelia growth rate and the growth morphology of Pch-1 *** the other hand,the culture filtrates of Pch-1

关键词： Pomelos black spot Phyllosticta citriasiana Culture filtrates Bioactivities

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拱序列的曲线描述与匹配

中国图象图形学报 2017年第8期22卷 1045-1055页

作者：危辉李俐复旦大学计算机科学技术学院上海201203

目的曲线匹配是计算机视觉和图像处理中的一个重要问题;判定几何图形形状相似性,得到与人类认知一致的结果,是目前的曲线描述与分类算法不能很好解决的问题。针对曲线匹配和几何图形形状的相似性判定,提出一种有效快速的基于拱序列的曲... 详细信息

目的曲线匹配是计算机视觉和图像处理中的一个重要问题;判定几何图形形状相似性,得到与人类认知一致的结果,是目前的曲线描述与分类算法不能很好解决的问题。针对曲线匹配和几何图形形状的相似性判定,提出一种有效快速的基于拱序列的曲线匹配与相似性判定算法。方法提取曲线的角点,将曲线表示为一连串相互重叠的拱序列。对于拱序列中的每一个拱,使用拱描述子进行描述。利用拱描述子,使用动态规划方法,实现对拱序列的匹配和相似性判定。结果为了验证本文算法,将基于拱序列的曲线描述与匹配方法应用于轮廓的拼接与几何图形的相似性比较。在轮廓拼接实验中,基于拱序列的曲线描述与匹配方法准确完成碎片轮廓的拼接和地图轮廓的拼接。在几何图形相似性的交叉度量实验中,基于拱序列的曲线描述与匹配方法可以准确反映出图形的相似程度,正确判断两幅图像是否属于同一类型。在判定不同相似程度的形状对的实验中,本文算法可以给出与人类判断相同的结果,相比较基于链码特征、多尺度不变量、形状上下文和GCT(geometry complex transform)变换算法,本文算法的距离值更好地反映出图像的相似程度。结论理论和实验表明,该算法可有效地描述曲线、匹配曲线,及准确判断几何图形的相似性,给出与人类视觉判定一致的结果。该算法可用于基于轮廓的图像拼接和几何图形相似性的判定。

关键词：曲线描述曲线匹配形状相似性拱序列动态规划

环境激励下基于chirplet变换的线性时变系统参数识别

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航空动力学报 2020年第1期35卷 9-17页

作者：张杰史治宇李利荣南京航空航天大学航空学院机械结构力学及控制国家重点实验室南京210016 中国商用飞机有限责任公司上海飞机客户服务有限公司上海200241

提出了针对时变系统响应的短时频率线性时变假设,通过将时变响应拟合成多分量线调频信号,根据线调频信号互相关理论推导了随机白噪声激励下时变系统的物理参数识别方法。该识别方法只需基于结构的加速度响应,便能识别结构的时变质量和... 详细信息

提出了针对时变系统响应的短时频率线性时变假设,通过将时变响应拟合成多分量线调频信号,根据线调频信号互相关理论推导了随机白噪声激励下时变系统的物理参数识别方法。该识别方法只需基于结构的加速度响应,便能识别结构的时变质量和刚度。由于引入了调频斜率刻画响应信号的短时频率线变特征,该方法相比传统识别方法能更好地追踪快变甚至突变参数,对实际工程中的时变问题具有重要的应用价值。仿真算例中构造了1个3自由度时变结构模型,针对线性时变、周期时变和突变等情况进行了物理参数的识别,误差分析显示识别误差均在5%以内,仿真结果验证了方法的正确性和适用性。

关键词：线调频小波变换加速度响应时变系统参数识别随机激励相关函数