检索结果-南通市图书馆

Foraging habitat selection of overwintering Black-necked Cranes in the farming area surrounding the Caohai Wetland, Guizhou Province, China

引用

Avian Research 2020年第1期11卷 74-82页

作者： dawei wu Canshi Hu Mingming Zhang Zhumei Li Haijun Su Forestry College Guizhou UniversityGuizhou 550025China Research Center for Biodiversity and Natural Conservation Guizhou UniversityGuizhou 550025China College of Life Sciences Guizhou UniversityGuizhou 550025China Key Laboratory of Plant Resources Conservation and Germplasm Innovation in Mountainous Region(Guizhou University) Ministry of EducationGuizhou 550025China Guizhou Institute of Biology Guizhou 550005China

Background: Understanding how overwintering birds choose foraging habitats is very important for conservation management. The overwintering Black-necked Crane(Grus nigricollis) feeds on crop remains in farmlands;thus, reasonable conservation management of this type of farmland that surrounds wetlands is critical for the overwintering populations of the Black-necked Crane;however, it is not clear how the Black-necked Crane chooses the foraging land in the ***: A thorough field positioning survey of all foraging sites in farmland areas around the Caohai Wetland and a-sampling analysis of habitat selection by the Black-necked Crane were conducted during the winters from 20162017 and ***: Multiple factors contributed to the selection of foraging habitat in farmlands, i.e., food factors(crop remains and tillage methods) > human disturbance factors(distance to road and settlement) > topography factors(slope aspect), listed according to the strength of influence. Additionally, Black-necked Cranes tend to choose farmland sites where there was no machine tillage, the crop remains were > 500 g/m^2, the distance to residences ranged from 100 to 500 m, the distance to roads ranged from 50 to 100 m, and the slopes exhibited western or eastern aspects. As the winters progressed, the volume of the edible crop remains declined, and the influences of the other main factors also changed, i.e., the factors of human disturbance(distance to road and settlement) became less important, while the effect of the food factor(crop remains) was strengthened. Thus, the foraging sites near the road became more ***: The farming area surrounding the Caohai Wetland is very important for the overwintering Black-necked Crane. Food factors and human disturbance factors are the main factors that influence the choice of feeding ground.

关键词： Black-necked Crane Caohai wetland in Guizhou Farmland around the wetland Foraging habitat selection Overwintering period

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Virtual flight test techniques to predict a blended-wing-body aircraft in-flight departure characteristics

引用

Chinese Journal of Aeronautics 2022年第1期35卷 215-225页

作者： Junquan FU Zhiwei SHI Zheng GONG Mark HLOWENBERG dawei wu Lijun PAN Nanjing University of Aeronautics and Astronautics Nanjing 210016China University of Bristol Bristol BS81TRUnited Kingdom CO MAC Shanghai Aircraft Design and Research Institute Shanghai 201210China

As one of the promising configurations of the next generation of commercial aircraft,research on departure characteristics of the Blended-Wing-Body(BWB)is of great signification to safe flight limits.A three-degree-of-freedom(3-DOF)virtual flight test in a wind tunnel has been implemented for a candidate configuration to predict the departure *** support mechanism,the test model and the control law of the virtual flight test are *** order to show the relationship between virtual flight test and actual flight test,the similarity criterion is also *** open loop,the model has mild oscillations in the longitudinal and lateral directions,which are stable in *** effect of flight control has been verified in virtual flight and actual subscale flight *** analysis of system identification results indicate that the model has a good response to the excitation signal,and the response is in reasonable agreement with the flight ***,the virtual flight departure test results are compared with the flight *** shows that there is a good correspondence between the angle of attack and the elevator deflection at *** gives promising evidence of the practicability of virtual flight testing to predict departure of a BWB.

关键词： Blended-wing-body Departure Flight test Similarity criterion Virtual flight test

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Defect detection in near-surface blind zone using Green’s function reconstruction of diffuse field sector scanning

引用

Chinese Journal of Acoustics 2021年第3期40卷 447-459页

作者： WANG Hanlu HE Liyuan MI Yuan wu dawei State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics Nanjing 210001

Aiming at the problem of defect detection in the near-surface blind zone of structure,the detection method for reconstruction of Green^function by sector scanning of diffuse field is *** on the theoretical analysis of the Green^function reconstruction of diffuse field sector scanning,a 5 MHz ultrasonic phased array probe is utilized to test the near-surface defects of an aluminum *** factors that affect the imaging results,such as the delay time,time window length and scanning methods,are further *** results show that this method can effectively detect defects from 1.5 mm to 3.0 mm in the near-surface blind zone of the aluminum *** effective diffusion time of the sector scanning method is longer than the full matrix capture method by more than 0.5 *** particularly,within the effective diffusion time,as the receiving delay time and the time window length increase,the imaging quality is *** research work provides an effective and feasible method for ultrasonic detection of defects in the near-surface blind zone.

关键词： function sector delay

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A Convergent Numerical Algorithm for the Stochastic Growth-Fragmentation Problem

引用

Annals of Applied Mathematics 2024年第1期40卷 71-104页

作者： dawei wu Zhennan Zhou School of Mathematical Sciences Peking UniversityBeijing 100871China Beijing International Center for Mathematical Research Peking UniversityBeijing 100871China

The stochastic growth-fragmentation model describes the temporal evolution of a structured cell population through a discrete-time and continuous-state Markov *** simulations of this stochastic process and its invariant measure are of *** this paper,we propose a numerical scheme for both the simulation of the process and the computation of the invariant measure,and show that under appropriate assumptions,the numerical chain converges to the continuous growth-fragmentation chain with an explicit error *** a triangle inequality argument,we are also able to quantitatively estimate the distance between the invariant measures of these two Markov chains.

关键词： Growth-fragmentation model Markov chain numerical approximation space discretization convergence rate

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Reactive capillary hemangiomas: a novel dermatologic toxicity following anti-PD-1 treatment with SHR-1210

引用

Cancer Biology & Medicine 2019年第1期16卷 173-180页

作者： Xuelian Chen Lanying Ma Xi Wang Hongnan Mo dawei wu Bo Lan Dong Qu Hongtu Zhang Jing Huang Binghe Xu State Key Laboratory of Molecular Oncology and Department of Medical Oncology National Cancer Center National Clinical Research Center for Cancer Cancer Hospital Chinese Academy of Medical Sciences & Peking Union Medical College-Medical Oncology Department of Gastroenterology Tumor Hospital Affiliated to Xinjiang Medical University Tumor Hospital Affiliated to Xinjiang Medical University Department of Diagnostic Radiology National Cancer Center National Clinical Research Center for Cancer Cancer Hospital Chinese Academy of Medical Sciences & Peking Union Medical College-Medical Oncology Department of Pathology National Cancer Center National Clinical Research Center for Cancer Cancer Hospital Chinese Academy of Medical Sciences & Peking Union Medical College-Medical Oncology

Objective: SHR-1210 is a new and promising anti-PD-1 agent for solid tumors. During the phase I study of SHR-1210, we encountered a novel but prevalent immune-related dermatologic toxicity: reactive capillary hemangiomas(RCHs). Thus we tried to summarize the features of RCHs and estimate their relationship with tumor ***: This prospective observational study systematically enrolled 98 patients with advanced solid tumors from April 27th,2016 to June 8th, 2017 in the context of the phase I clinical study of SHR-1210. This report focused on the skin toxicities. Patients underwent entire skin inspection every two weeks while taking medication. The clinical course of RCHs was recorded and their association with tumor response was estimated. The data cut-off date was November 15th, ***: After a median follow-up of 242(range, 29–567) days, RCHs were observed in 85.7%(84/98) of patients on cutaneous/mucosal surfaces; 84.5%(71/84) of the RCHs were evaluated as grade 1 adverse events. No grade 3 or 4 RCHs were observed. The time of onset of RCHs was dose dependent and shortest in the 400 mg-dose cohort(P < 0.001). Spontaneous and complete regression of RCHs was observed both during and after treatment. The objective response rate of tumors for patients with RCHs was 28.9%(24/83). However, no responders were observed among the patients without ***: RCHs were prevalent but manageable during treatment with SHR-1210. It might add to the expanding literature regarding immune-related dermatologic adverse events.

关键词： Reactive capillary hemangiomas SHR-1210 skin toxicity anti-tumor efficacy

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

油藏渗流–应力耦合分析的FEM-FVM混合方法的改进

引用

岩石力学与工程学报 2020年第S1期39卷 2645-2654页

作者：邸元吴大卫 wu Yushu 北京大学工学院北京100871 科罗拉多矿业学院石油工程系美国戈尔登CO80401

在油藏开采过程中,岩石应力场变化的波及范围远大于发生渗流的储层区域,因而现有渗流–应力全耦合方法数值模拟的计算量往往十分巨大。为了提高数值模拟的计算效率,考虑渗流计算区域和应力计算区域的差异,对FEM-FVM(有限元–有限体积)... 详细信息

在油藏开采过程中,岩石应力场变化的波及范围远大于发生渗流的储层区域,因而现有渗流–应力全耦合方法数值模拟的计算量往往十分巨大。为了提高数值模拟的计算效率,考虑渗流计算区域和应力计算区域的差异,对FEM-FVM(有限元–有限体积)混合方法进行了改进。对储层渗流区域采用细密的网格进行计算,以获得地下流体较为准确的分布情况;对应力计算区域则采用粗网格进行计算,从而降低计算耗时。全耦合理论中的力学平衡方程采用有限元法在粗网格上进行离散;质量守恒方程则在细网格上采用有限体积法进行离散。对Terzaghi一维固结问题和Mandel二维固结问题的数值模拟表明,该方法的计算结果与解析解吻合较好。通过对一个二维单相流单井开采问题和一个三维两相流五点井网开采问题的数值计算,分析了油藏数值模拟中渗流–应力耦合效应的影响。

关键词：岩石力学油藏数值模拟渗流–应力耦合有限体积法有限元法耦合问题

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

National Report on Space Medicine Progress

引用

空间科学学报 2018年第5期38卷 814-819页

作者： LI Yinghui LI Weigang DING Bai wu dawei LIU Zhaoxia HE Li ZHOU Wanlong XU Zi Institute of Space Medico-Engineering Beijing 100094

The development of Chinese manned space engineering has a great role in promoting the progress of Chinese space medicine. With the accelerated implementation of Chinese Space Station Program, China's space medicine has made fruitful achievements over the past three years. This report summarizes the major progress of Chinese space medicine in terms of basic research and space applications from 2016 to 2018.

关键词：空间工程空间应用中国太空站空格

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

基于GPS TEC的2022年1月15日汤加火山喷发激起的电离层行扰分析

引用

测绘学报 2024年第4期53卷 629-643页

作者：罗亦泳吴大卫东华理工大学测绘工程学院江西南昌330013

2022年1月15日南太平洋汤加海底火山发生剧烈喷发,是近30年来最大规模的火山爆发,产生的强烈大气波动为开展火山喷发电离层扰动研究提供了难得的机会。本文利用GPS数据探测火山附近、新西兰、澳大利亚和中国地区的电离层扰动,从波形、... 详细信息

2022年1月15日南太平洋汤加海底火山发生剧烈喷发,是近30年来最大规模的火山爆发,产生的强烈大气波动为开展火山喷发电离层扰动研究提供了难得的机会。本文利用GPS数据探测火山附近、新西兰、澳大利亚和中国地区的电离层扰动,从波形、频率、传播速度和时空分布等角度分析汤加火山喷发电离层行扰(TIDs)的特征,并利用电离层测高站、海平面监测站和大气压监测站的观测数据进一步验证TIDs的传播特征。研究结果发现,汤加火山喷发在其附近区域、新西兰、澳大利亚和中国地区引起了3类TIDs。在火山附近东、西、南、北方向上均探测到第一类TIDs, TIDs的传播速度为617~972 m/s,该类TIDs极有可能由火山喷发产生的声波引起。汤加火山喷发仅在火山附近东、西方向引起第二类TIDs,其传播速度分别为472 m/s和418 m/s,可能由声波传播过程中衍生的声重力波或者混合波引起,形成机理有待进一步研究。汤加火山喷发在新西兰、澳大利亚和中国地区引发了第三类TIDs,其传播速度为328~352 m/s,该类TIDs与Lamb波密切相关。

关键词：汤加火山全球导航卫星系统电离层行扰电离层总电子含量

来源：

维普期刊数据库

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

彩色骨髓相的快速分割

引用

清华大学学报（自然科学版） 2005年第7期45卷 951-954页

作者：吴大伟俞昌清华大学电子工程系北京100084

为了利用计算机进行髓相分析,对在彩色空间中复杂背景下的目标分割问题作了研究。提出了在处理后的色度和饱和度分量的融合图像上,根据改进的最大熵二值化算法在两个层面上对细胞核进行多级分割,解决复杂背景下细胞核及粘连细胞核的分... 详细信息

为了利用计算机进行髓相分析,对在彩色空间中复杂背景下的目标分割问题作了研究。提出了在处理后的色度和饱和度分量的融合图像上,根据改进的最大熵二值化算法在两个层面上对细胞核进行多级分割,解决复杂背景下细胞核及粘连细胞核的分割问题。再由细胞核外周对空间作搜索,根据统计方法确定的点集性质一次性地对细胞胞浆做分割,最后分析细胞的几何特征,对分割进行调整。实验结果表明:整个算法适应性强,对不同性质的骨髓图像均有较好的分割效果,且与其他血细胞分割方法相比计算量小,比较快捷,约86%的细胞得到了正确分割。

关键词：图像信号处理骨髓相多级分割

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

OXA-23 overproduction caused by insertion sequence ISAbal is associated with resistance to imipenem in Acinetobacter baumannii

OXA-23 overproduction caused by insertion sequence ISAbal is...

引用

中华医学会第七次全国中青年检验医学学术会议

作者： dawei wu DianJun Wei QuanLing Ma The Laboratory of Medicine The Second HospitalTianjin Medical University

A total of eight Imipenem-resistant Acinetobacter baumannii isolates were tested for the presence of blaOXA-23 carbapenemase *** amplification revealed the gene was positive in all isolates and the ISAbal was located ...

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：