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大九湖泥炭藓沼泽植被指数时空变化研究

地理空间信息 2024年第4期22卷 106-110页

作者：张唯张振泽刘福江梁天欣中国地质大学(武汉)地理与信息工程学院湖北武汉430000

基于Landsat系列卫星数据,计算大九湖泥炭藓沼泽地区1986-2021年的归一化植被指数(NDVI),利用Theil-Sen median趋势分析和Mann-Kendall显著性检验方法,结合研究区气象资料,分析近36 a来植被指数的时空演变规律。结果表明:①植被指数变化... 详细信息

基于Landsat系列卫星数据,计算大九湖泥炭藓沼泽地区1986-2021年的归一化植被指数(NDVI),利用Theil-Sen median趋势分析和Mann-Kendall显著性检验方法,结合研究区气象资料,分析近36 a来植被指数的时空演变规律。结果表明:①植被指数变化在2005年存在明显的拐点。1986-2005年总体呈退化趋势,显著和微显著退化的面积占比约60.38%;2006-2021年则总体呈改善趋势,显著和微显著改善的面积占比约81.5%。②泥炭藓斑块与沼泽区域植被指数的变化基本一致,但前期退化的幅度明显高于后期的改善幅度。③研究区植被指数相比气温和降水存在明显的滞后性,NDVI滞后于气温一个月,滞后于降水3个月。④1986-2020年,研究区NDVI对降水的响应更稳定,且集中在中部泥炭藓覆盖度较高区域,这与泥炭藓植被的生态特性基本一致。

关键词： NDVI 时序分析泥炭藓沼泽气候因子相关分析

Shock-Resistant and Energy-Absorbing Properties of Bionic NiTi Lattice Structure Manufactured by SLM

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Journal of Bionic Engineering 2022年第6期19卷 1684-1698页

作者： Zhenglei Yu Renlong Xin Zezhou Xu Luming Sha Lixin Chen Yining Zhu Ping Liang Zhihui Zhang zhenze Liu Qing Cao College of Communication Engineering Jilin UniversityChangchun130022China Key Laboratory of Engineering Bionics Ministry of EducationJilin UniversityChangchun130022China State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchun130022China School of Agriculture Yanbian UniversityYanji133002China

Each specific structure of organisms is the best choice under specific *** excellent characteristic structures of these organisms have great application potential in the design and multi-functional optimization of energy-absorbing structures such as vehicle collisions,satellite landings,and military *** this paper,using the principle of structural bionics,using the advantages of the honeycomb structure and the light weight and high strength of beetle elytra,four bionic lattice structures are studied:CH,ZPRH,SCH and *** NiTi shape memory alloy,a unique material as the base material,samples are prepared using selective laser melting(SLM)*** comparing the test results of the quasi-static compression test with the results of the numerical simulation,it is found that compared with the other three bionic lattice structures,the SCH structure has the best energy absorption effect in the effective stroke in the test,and the specific energy absorption can reach 6.32 J/***,SCH,and IBE structures not only have good and stable deformation behavior,but also have excellent impact resistance and shape memory *** design of these structures provides a reference for the design of anti-shock cushioning structures with self-recovery functions in the future.

关键词： Engineering bionics Bionic structural design Additive manufacturing Quasi-static compression Numerical simulation Shape memory effect

ANALYTICAL SOLUTIONS FOR THE LAYERED GEO-MATERIALS SUBJECTED TO AN ARBITRARY POINT LOAD IN THE CARTESIAN COORDINATE

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Acta Mechanica Solida Sinica 2011年第3期24卷 262-272页

作者： Zhiguo Zhang zhenze Li Department of Civil Engineering Shanghai University Shanghai 200072 China Department of Geotechnical Engineering Tongji University Shanghai 200092 China Shanghai Institute of Applied Mathematics and Mechanics Shanghai 200072 China JSPS Postdoctoral Fellow Laboratory of Professor Katsumi Graduate School of Global Environmental Study Kyoto University Sakyo Kyoto 606-8501 Japan

This paper presents analytical solutions for the stress and displacement field in elastic layered geo-materials induced by an arbitrary point load in the Cartesian coordinate system. The point load solutions can be obtained by referring to the integral transform and the transfer matrix technique. However, former solutions usually exist in the cylindrical coordinate system subjected, to axisymmetric loading. Based on the proposed solutions in the Cartesian coordinate, it is very easy to solve asymmetric problems and consider the condition with internal loads in multi-layered geo-materials. Moreover, point load solutions can be used to construct solutions for analytical examination of elastic problems and incorporated into numerical schemes such as boundary element methods. The results discussed in this paper indicate that there is no problem in the evaluation of the point load solutions with high accuracy and efficiency, and that the material non-homogeneity has a significant effect on the elastic field due to adjacent loading.

关键词： layered geo-material Cartesian coordinate non-homogeneity Fourier transformtransfer matrix technique

小儿解表口服液治疗流行性感冒(风热犯卫证)多中心随机对照临床研究

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中华中医药学刊 2024年第5期42卷 131-136页

作者：穆婧雯王雪峰王梅崔振泽王孟清尚莉丽刘英尹庆锋迟磊张秀英沈红岩辽宁中医药大学辽宁沈阳110847 辽宁中医药大学附属医院辽宁沈阳110032 大连市儿童医院辽宁大连116011 湖南中医药大学第一附属医院湖南长沙410007 安徽中医药大学第一附属医院安徽合肥230031 江西中医药大学附属医院江西南昌330006 江苏法迈生医学科技有限公司江苏南京210000

目的评价小儿解表口服液治疗流行性感冒(风热犯卫证)的疗效及其安全性。方法采用分层区组随机、阳性药平行对照、多中心临床试验设计。计划纳入300例受试儿童,随机分为治疗组和对照组。治疗组予小儿解表口服液,对照组予磷酸奥司他韦颗粒... 详细信息

目的评价小儿解表口服液治疗流行性感冒(风热犯卫证)的疗效及其安全性。方法采用分层区组随机、阳性药平行对照、多中心临床试验设计。计划纳入300例受试儿童,随机分为治疗组和对照组。治疗组予小儿解表口服液,对照组予磷酸奥司他韦颗粒,疗程5 d。比较两组疾病临床痊愈时间,完全退热时间,加拿大急性呼吸道疾病和流感量表(Canadian Acute Respiratory Illness and Flu Scale,CARIFS)评分,中医证候疗效,单项症状消失率,退热持续时间,并发症、重症及危重症发生率,和安全性指标。结果共纳入临床诊断患儿300例,其中297例进入全分析数据集(Full a⁃nalysis set,FAS),289例进入符合方案数据集(Per protocol set,PPS),297例进入安全性数据集(Safety set,SS)。治疗后,疾病临床痊愈中位时间,组间比较差异均无统计学意义(P>0.05),采用COX回归分析,按0.75的非劣标准,治疗组非劣效于对照组,PPS与FAS分析结论一致;完全退热中位时间,组间比较,FAS/PPS分析差异无统计学意义(P>0.05),采用COX回归分析,按0.75的非劣标准,治疗组非劣效于对照组;流涕消失率治疗组优于对照组,差异有统计学意义(P0.05)。结论小儿解表口服液治疗儿童流行性感冒(风热犯卫证)具有缩短病程作用,疗效非劣于磷酸奥司他韦颗粒,临床应用的安全性较好。

关键词：小儿解表口服液儿童流行性感冒风热犯卫证随机对照临床试验

Oxygen vacancy O-terminated surface:The most exposed surface of hexagonal WO3(001)surface

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Chinese Chemical Letters 2020年第8期31卷 2095-2098页

作者： Feng Hui Tian zhenze Liu Jin Tian Yunfan Zhang Institute of Computational Science and Engineering State Key Laboratory of Bio-Fibers and Eco-Textiles&College of Chemistry and Chemical Engineering&College of Environmental Science and EngineeringQingdao UniversityQingdao 26607 JChina

It is known that exposed surface determines material’s ***3 is widely used in gas sensing and its working surface is proposed to control its ***,the working surface,or most exposed surface with detailed surface structure remain *** this paper,DFT calculation confirmed that oxygen vacancy O-terminated surface is the most exposed hexagonal WO3(001)surface,judging from competitive adsorption of CO and O2,working surface determination for CO sensing and comparison of oxygen vacancy formation ene rgies on different h-WO3(001)*** is found that DFT can be a useful alternate for exposed surface *** results provide new perspectives and performance explanations for material research.

关键词： Hexagonal WO3(001) Oxygen vacancy O-terminated surface Competitive adsorption Working surface Exposed surface determination theoretically

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宋代记注官直前奏事考论

史学月刊 2022年第5期 36-45页

作者：蒋振泽中山大学历史学系广东广州510275

宋代一般官员奏事,需经中书请旨后牒知閤门;直前奏事的官员,则可免申中书,直牒閤门。北宋中期以前的记注官不能直前奏事,神宗熙宁四年,张琥凭借记注兼谏官的身份,争取到免牒直前的奏事特权。元丰二年,允许不兼谏职的普通记注官后殿直前... 详细信息

宋代一般官员奏事,需经中书请旨后牒知閤门;直前奏事的官员,则可免申中书,直牒閤门。北宋中期以前的记注官不能直前奏事,神宗熙宁四年,张琥凭借记注兼谏官的身份,争取到免牒直前的奏事特权。元丰二年,允许不兼谏职的普通记注官后殿直前陈述史事。南宋绍兴三年,宋廷重申元丰二年诏令,普通记注官稳定地享有了直前奏事的权力,奏事内容逐渐突破史事的限制。隆兴元年,通过左右史胡铨、王十朋的奏请,普通记注官最终获得免牒特权。宋代记注官的奏事权,与皇权、相权之消长密切相关。君主将“二史直前”视作下情上达的“言路”之一,为防范大臣壅蔽,选择支持记注官直前奏事。通过掌管信息通进的閤门,皇帝可对记注官直前奏事进行干预,将其纳入可操控的范围之内。

关键词：宋代记注官直前奏事

Individualized Design of the Ventilator Mask based on the Residual Concentration of CO2

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Computer Modeling in Engineering & Sciences 2018年第11期117卷 157-167页

作者： Zhiguo Zhang Zhenxiao Li Yifei Zhang zhenze Wang Minzhou Luo Jiangsu Key Laboratory of Special Robot Technology College of Mechanical and Electrical EngineeringHohai UniversityNo.200.Jinling North RoadXinbeiChangzhou213022China School of Mechanical Engineering Changzhou UniversityNo.1.Gehu RoadWujinChangzhou213164China School of Mathematics&Physics Changzhou UniversityNo.1.Gehu RoadWujinChangzhou213164China National Research Center for Rehabilitation Technical Aids Beijing Key Laboratory of Rehabilitation Technical Aids for Old-Age DisabilityKey Laboratory of Rehabilitation Technical Aids Technology and System of the Ministry of Civil AffairsNo.1.Ronghuazhong RoadBeijing BDABeijing100176China.

OSAHS(Obstructive Sleep Apnea Hypopnea Syndrome)is a respiratory disease mainly characterized by limited and repeated pauses of breathing in ***,the optimal treatment is to apply CPAP(Continuous Positive Airway Pressure)ventilation on the upper airway of the patient through a household respiratory ***,if the ventilator mask is designed improperly,it might cause the residue and repeated inhalation of CO2,which will exert an adverse impact on the therapeutic *** research numerically analyzed the CO2 transportation inside a commercial ventilator mask(Mirage SoftGel,ResMed,Australia)based on the reconstructed 3D numerical model of a volunteer's face and performed the improved design of the ventilator mask in terms of the CO2 residual concentration below the *** fluid dynamic analyses showed that at the end time of expiratory,the CO2 residual concentration below the nostrils is close to 4%.To improve the therapeutic effect,we changed the position of the exhaust holes and found that by moving the exhaust holes to the bottom of the ventilator mask,the CO2 residual concentration below the nostrils would be reduced to no more than 1%.This study established a near physiological computational model and provided a new method for the individualized design of the commercial ventilator mask.

关键词： Obstructive sleep apnea hypopnea syndrome continuous positive airway pressure ventilator mask CO2 residual concentration 3D numerical reconstruction.

Accuracy of pedicle screw placement in the thoracic and lumbosacral spines using O-arm-based navigation versus conventional freehand technique

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Chinese Neurosurgical Journal 2019年第3期5卷 137-143页

作者： Linkai Jing zhenze Wang Zhenxing Sun Huifang Zhang James Wang Guihuai Wang School of Clinical Medicine Tsinghua UniversityBeijing 100084China Department of Neurosurgery Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 102218China

The accuracy and safety of pedicle screw insertion was markedly improved with the introduction of intraoperative three-dimensional navigation system during the last decade. This study aimed to evaluate the accuracy of pedicle screw placement using O-arm-based navigation system versus conventional freehand technique. Methods: We reviewed the accuracy of 341 thoracic (n = 173) and lumbosacral (n = 168) pedicle screws placed in 60 consecutive patients using either O-arm-based navigation or freehand technique in the Department of Neurosurgery of Beijing Tsinghua Changgung Hospital between January 2015 and June 2018. Patient-specific characteristics, treatment-related characteristics, and screw-specific accuracy were analyzed. The accuracy of pedicle screw placement was measured by Gertzbein-Robbins scale and screw grades A and B were clinically acceptable. Results: One hundred ninety-one screws were inserted in the O-arm-based navigation group and 150 in the freehand group. One hundred eighty-three (95.81%) clinically acceptable screws were placed in the navigation group and 135 (90.00%) in the freehand group (p = 0.034). Twenty-three (6.74%) screw revisions were performed in the two groups (8 screws in the navigation group and 15 screws in the freehand group) and significant difference was observed in thoracic spine (p = 0.018), while no statistical significance was presented in lumbosacral spine (p >0.05). Twenty-four (12.57%) screws in the navigation group and 24 (16.00%) in the freehand group violated the cortex (p > 0.05). Medial screw deviation was the most common problem in the two groups. Conclusion: The O-arm-based navigation exhibits higher accuracy for pedicle screw insertion than the freehand insertion technique.

关键词： Accuracy Freehand Navigation O-arm Pedicle screw

Hydro-mechanical behavior of an argillaceous limestone considered as a potential host formation for radioactive waste disposal

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第6期10卷 1063-1081页

作者： T.S.Nguyen zhenze Li Grant Su M.H.B.Nasseri R.P.Young Canadian Nuclear Safety Commission OttawaCanada Department of Civil Engineering University of TorontoTorontoCanada

The Canadian Nuclear Safety Commission(CNSC), Canada’s nuclear regulator, conducts regulatory research in order to develop independent knowledge on safety aspects related to the deep geological disposal of radioactive wastes. In Canada, the Cobourg limestone of the Michigan Basin is currently considered as a potential host formation for geological disposal. The understanding of the hydromechanical behavior of such a host rock is one of the essential requirements for the assessment of its performance as a barrier against radionuclide migration. The excavation of galleries and shafts of a deep geological repository(DGR) can induce damage to the surrounding rock. The excavation damaged zone(EDZ) has higher permeability and reduced strength compared to the undisturbed rock and those factors must be considered in the design and safety assessment of the DGR. The extent and characteristics of the EDZ depend on the size of the opening, the rock type and its properties, and the in situ stresses, among other factors. In addition, the extent and characteristics of the EDZ can change with time due to rock strength degradation, evolution of fractures within the EDZ, and the redistribution of pore pressure around the excavation. In this research project initiated by the CNSC, the authors conducted experimental and theoretical research in order to assess the hydro-mechanical behavior of the Cobourg limestone under undamaged and damaged conditions, both in the short and long terms. The short-term behavior was investigated by a program of triaxial tests with the measurement of permeability evolution on specimens of Cobourg limestone. The authors formulate a coupled hydro-mechanical model to simulate the stress-strain response and evolution of the permeability during those triaxial tests. Using creep and relaxation data from a similar limestone, the model was extended to include its long-term strength degradation. The model successfully simulated both the short-and long-term hydro-me

关键词： Hydro-mechanical behavior Excavation damage Deep geological repository(DGR) Limestone Poro-elasto-plasticity