检索结果-南通市图书馆

Nonlinear uncertainty impact of geometric variations on aerodynamic performance of low-pressure turbine blades with ultra-high loading under extreme operational conditions

引用

Chinese Journal of Aeronautics 2024年第5期37卷 281-300页

作者： Xiaojing WANG Zhengping ZOU chao fu Pengcheng DU School of Energy and Power Engineering Beihang UniversityBeijing 100191China National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics Beihang UniversityBeijing 100191China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China

Uncertainty impact of random geometric variations on the aerodynamic performance of low-pressure turbine blades is considerable,which is further amplified by the current ultra-high-lift design trend for weight ***,this uncertainty impact on ultra-highly loaded blades under extreme operational conditions near the margins with potential large-scale open separation is focused on in this *** is demonstrated that this impact is significant,unfavourable,and nonlinear,which is clearly severer under extreme *** addition to the overall attenuation and notable scattering of specific performance,the operational margins with open separation are also notably scattered with great risk of significant *** scattering and nonlinearity are dominated by the variations in leading-edge *** thinning of leading edge triggers local transition,enhancing downstream friction and reducing resistance to open separation,which is further exacerbated by operational ***,the opposite thickening yields less benefit,implying *** unfavourable impact highlights the need for robust aerodynamic design,where both a safer operational condition and a more robust blade are indispensable,i.e.,a compromise among performance,weight,and *** the necessary limitation of loading levels,a mid-loaded design is recommended to reduce adverse pressure gradients in both the leading edge and rear region of the suction side,which helps to decrease the susceptibility of the transition and open separation to random *** improvements can also be achieved by appropriately thickening the leading edge.

关键词： Ultra-highly loaded turbine blade Geometric variations Uncertainty analysis Operational margins Robust aerodynamic design Nonlinearity

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

Off-farm employment,agriculture production activities,and household dietary diversity in environmentally and economically vulnerable areas of Asia

引用

Journal of Integrative Agriculture 2024年第2期23卷 359-373页

作者： Yunli Bai Xuanye Zeng chao fu Linxiu Zhang Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China United Nations Environment Programme-International Ecosystem Management Partnership(UNEP-IEMP) Beijing 100101China University of Chinese Academy of Sciences Beijing 100101China

Access to off-farm employment has been expected to be a critical approach to ending hunger and all forms of malnutrition,two important targets of achieving Zero *** study aims to investigate the role of off-farm employment in improving dietary diversity through substitution effect and complementary effect with agricultural production activities and income *** study adopts Poisson/Tobit/Probit/OLS regressions and the instrument variable method based on the primary survey data collected among 1,282 households at 12 sites in environmentally and economically vulnerable areas of China,Nepal,Cambodia,Thailand,and Myanmar in *** results show that off-farm employment is positively associated with household dietary diversity and the consumption of flesh meat,fish and other aquatic animals,fruits,and milk and dairy products,which are rich in protein and *** results of mechanism analysis show that off-farm employment contributes to household dietary diversity by improving crop diversity,especially for poor households,boosting the probability of livestock raising for households with the middle one-third disposal income,and increasing household *** positive association between off-farm employment and household dietary diversity is much higher for households with the bottom one-third disposal income,low illiteracy,and from upper-middle income *** findings imply that off-farm employment does play a vital role in achieving multiple benefits of poverty alleviation,malnutrition reduction,and agrobiodiversity conservation in environmentally and economically vulnerable ***,it may enlarge the gaps in dietary diversity between households with low human capital and from low and lower-middle income countries and those with high human capital and from middle-high countries.

关键词： off-farm employment dietary diversity income effect substitution effect complementary effect

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

Deep learning CNN-APSO-LSSVM hybrid fusion model for feature optimization and gas-bearing prediction

引用

Petroleum Science 2024年第4期21卷 2329-2344页

作者： Jiu-Qiang Yang Nian-Tian Lin Kai Zhang Yan Cui chao fu Dong Zhang College of Earth Sciences and Engineering Shandong University of Science and Technology Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Transportation Institute of Inner Mongolia University Key Laboratory of Gas Hydrate Qingdao Institute of Marine Geology Ministry of Natural Resources

Conventional machine learning(CML) methods have been successfully applied for gas reservoir prediction. Their prediction accuracy largely depends on the quality of the sample data; therefore, feature optimization of the input samples is particularly important. Commonly used feature optimization methods increase the interpretability of gas reservoirs; however, their steps are cumbersome, and the selected features cannot sufficiently guide CML models to mine the intrinsic features of sample data efficiently. In contrast to CML methods, deep learning(DL) methods can directly extract the important features of targets from raw data. Therefore, this study proposes a feature optimization and gas-bearing prediction method based on a hybrid fusion model that combines a convolutional neural network(CNN)and an adaptive particle swarm optimization-least squares support vector machine(APSO-LSSVM). This model adopts an end-to-end algorithm structure to directly extract features from sensitive multicomponent seismic attributes, considerably simplifying the feature optimization. A CNN was used for feature optimization to highlight sensitive gas reservoir information. APSO-LSSVM was used to fully learn the relationship between the features extracted by the CNN to obtain the prediction results. The constructed hybrid fusion model improves gas-bearing prediction accuracy through two processes of feature optimization and intelligent prediction, giving full play to the advantages of DL and CML methods. The prediction results obtained are better than those of a single CNN model or APSO-LSSVM model. In the feature optimization process of multicomponent seismic attribute data, CNN has demonstrated better gas reservoir feature extraction capabilities than commonly used attribute optimization methods. In the prediction process, the APSO-LSSVM model can learn the gas reservoir characteristics better than the LSSVM model and has a higher prediction accuracy. The constructed CNN-APSO-LSSVM mode

关键词： Multicomponent seismic data Deep learning Adaptive particle swarm optimization Convolutional neural network Least squares support vector machine Feature optimization Gas-bearing distribution prediction

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Present situation and prospect of immunotherapy for unresectable locally advanced esophageal cancer during peri-radiotherapy

引用

World Journal of Gastrointestinal Oncology 2024年第1期16卷 1-7页

作者： Feng-Mei Wang Peng Mo Xue Yan Xin-Yue Lin Zhi-chao fu Department of Obstetrics and Gynecology Fuzong Clinical Medical College(900th Hospital)Fujian Medical UniversityFuzhou 350025Fujian ProvinceChina Department of Obstetrics and Gynecology Dongfang HospitalXiamen UniversityFuzhou 350025Fujian ProvinceChina Department of Radiotherapy Fuzong Clinical Medical College(900th Hospital)Fujian Medical UniversityFuzhou 350025Fujian ProvinceChina Department of Radiotherapy Dongfang HospitalXiamen UniversityFuzhou 350025Fujian ProvinceChina

Four major studies(Checkmate577,Keynote-590,Checkmate649 and Attraction-4)of locally advanced esophageal cancer published in 2020 have established the importance of immunotherapy,represented by anti-programmed death protein(PD)-1 in postoperative adjuvant treatment and advanced first-line treatment of locally advanced or advanced esophageal cancer and esophagogastric junction cancer,from the aspects of proof of concept,long-term survival,overall survival rate and progression-free *** unresectable or inoperable nonmetastatic esophageal cancer,concurrent radiotherapy and chemotherapy is the standard treatment recommended by various *** its curative effect is still not ideal,it is necessary to explore radical radiotherapy and chemotherapy in the future,and it is considered to be promising to combine them with immunotherapeutic drugs such as *** paper mainly discusses how to combine radical concurrent radiotherapy and chemotherapy with immunotherapy for unresectable local advanced esophageal cancer.

关键词： Esophageal carcinoma Locally advanced Radiotherapy Immunotherapy

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

一份珍贵的学术遗产:1950年代民族问题大讨论再审视

引用

河北学刊 2024年第1期44卷 45-52页

作者：晁福林北京师范大学铸牢中华民族共同体意识研究基地

1950年代关于民族问题的大讨论,开启了中国史学界以马克思主义理论为指导研究民族问题的热潮。当时学习的重点是斯大林关于形成民族的四个要素。斯大林强调依照这四个要素衡量,在资本主义出现之前,不可能出现民族,民族只能是资本主义时... 详细信息

1950年代关于民族问题的大讨论,开启了中国史学界以马克思主义理论为指导研究民族问题的热潮。当时学习的重点是斯大林关于形成民族的四个要素。斯大林强调依照这四个要素衡量,在资本主义出现之前,不可能出现民族,民族只能是资本主义时代的产物。范文澜注意到斯大林论断的适用性问题,著文指出中、欧历史情况不同。欧洲历史进入资本主义时代才有了民族国家,而古代中国早在秦汉时期就已经有了“持久的相当巩固的整体”的王朝国家,“汉民族有它自己的发展过程,并不因为有了资本主义才开始形成民族”。围绕汉民族形成时间问题所展开的大讨论实际上是在马克思主义理论指导下成规模地研讨中华民族形成问题的嚆矢。这场大讨论的丰富成果是一份珍贵的学术遗产。

关键词：民族汉民族形成中华民族资本主义 1950年代

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

Assessing and Comparing Smallholders’Vulnerability to Climate Change among Countries in the Pan-Third Pole Region

引用

Journal of Resources and Ecology 2024年第4期15卷 1015-1026页

作者： XU Xiangbo XU Ce LI Chang fu chao ZHOU Yunqiao Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China International Ecosystem Management Partnership United Nations Environment ProgrammeBeijing 100101China Land Consolidation and Rehabilitation Center Ministry of Natural ResourcesBeijing 100035China Technology Innovation Center for Land Engineering Ministry of Natural ResourcesBeijing 100035China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Tibetan Plateau Earth System Resources and EnvironmentInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

A comprehensive assessment of climate change vulnerability is imperative for formulating effective adaptation strategies and advancing sustainable development *** one of the most climate-vulnerable regions globally,the Pan-Third Pole area lacks transnational vulnerability assessments,which poses a significant obstacle to efficient climate *** study conducted transnational comparisons based on primary micro-survey data collected uniformly across Nepal,Cambodia,Thailand,and Myanmar,which are all located in the Pan-Third Pole *** and comparing the vulnerabilities employed an extended framework of climate change *** findings reveal substantial variations in vulnerability among the countries,with Cambodia exhibiting the highest vulnerability,followed by Thailand,Myanmar,and Nepal in descending order,primarily due to differences in *** exposure to climate change also varied *** scores decreased in the order of Nepal>Cambodia>Thailand>Myanmar,with demographic factors,tap water accessibility,and land being the major contributors and sources of differentiation among the *** adaptability,Thailand demonstrated the highest adaptability,with human and financial capital as the key *** outcomes underscore the need for tailored policy measures addressing the diverse vulnerabilities,including enhancing household disaster prevention and capital ***,targeted international investments are crucial for improving adaptability among smallholders in this unique region.

关键词： climate change vulnerability smallholder sustainable development Pan-Third Pole region

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

基于深度学习的图像匹配:方法、应用与挑战

引用

计算机学报 2024年第7期47卷 1485-1520页

作者：孔庆群吴福朝樊彬中国科学院自动化研究所北京100190 中国科学院大学北京100049 北京科技大学智能科学与技术学院北京100083

图像匹配旨在建立图像之间的点对应关系,是许多计算机视觉任务的关键环节.近年来,随着深度学习技术的发展,图像匹配方法已从以手工设计特征为主转变为基于深度网络的方法,基于深度学习的图像匹配方法在多个标准数据集上展现出卓越的性能... 详细信息

图像匹配旨在建立图像之间的点对应关系,是许多计算机视觉任务的关键环节.近年来,随着深度学习技术的发展,图像匹配方法已从以手工设计特征为主转变为基于深度网络的方法,基于深度学习的图像匹配方法在多个标准数据集上展现出卓越的性能,推动着多个相关应用的发展围绕图像匹配涉及的若干关键问题,如:特征点检测、特征点描述、稠密点匹配、误匹配去除,本文对深度学习图像匹配方法进行了系统性总结.首先分析了领域内基于深度学习的典型方法和关键技术,随后介绍了与图像匹配密切相关的几个典型应用并给出其现状分析,最后,根据对图像匹配领域技术发展的分析总结,结合作者在该领域的长期研究积累,本文给出了目前图像匹配所面临的主要挑战以及未来发展趋势。

关键词：图像匹配特征点匹配稠密匹配三维重建视觉定位同时定位与建图深度学习

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

Anti-metabolic agent pegaspargase plus PD-1 antibody sintilimab for first-line treatment in advanced natural killer T cell lymphoma

引用

Signal Transduction and Targeted Therapy 2024年第4期9卷 1665-1674页

作者： Jie Xiong Shu Cheng Xiao Gao Shan-He Yu Yu-Ting Dai Xin-Yun Huang Hui-Juan Zhong chao-fu Wang Hong-Mei Yi Hao Zhang Wei-Guo Cao Rong Li Wei Tang Yan Zhao Peng-Peng Xu Li Wang Wei-Li Zhao Shanghai Institute of Hematology State Key Laboratory of Medical GenomicsNational Research Center for Translational Medicine at ShanghaiRuijin Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghaiChina Department of Nuclear Medicine Shanghai Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghaiChina Department of Pathology Shanghai Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghaiChina Department of Otolaryngology Shanghai Rujin HospitalShanghai Jiao Tong University School of MedicineShanghaiChina Department of Radiation Shanghai Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghaiChina Department of Hematology Navy Medical Center of PLAShanghaiChina Pole de Recherches Sino-Francais en Science du Vivant et Genomique Laboratory of Molecular PathologyShanghaiChina

Natural killer T cell lymphoma(NKTCL)is highly aggressive,with advanced stage patients poorly responding to intensive *** explore effective and safe treatment for newly diagnosed advanced stage NKTCL,we conducted a phase ll study of anti-metabolic agent pegaspargase plus PD-1 antibody sintilimab(NCT04096690).Twenty-two patients with a median age of 51 years(range,24-74)were enrolled and treated with induction treatment of pegaspargase 2500 IU/m2 intramuscularly on day 1 and sintilimab 200 mg intravenously on day 2 for 6 cycles of 21 days,followed by maintenance treatment of sintilimab 200 mg for 28 cycles of 21 *** complete response and overall response rate after induction treatment were 59%(95%Cl,43-79%)and 68%(95%Cl,47-84%),*** a median follow-up of 30 months,the 2 year progression-free and overall survival rates were 68%(95%Cl,45-83%)and 86%(95%Cl,63-95%),*** most frequently grade 3/4 adverse events were neutropenia(32%,n=7)and hypofibrinogenemia(18%,n=4),which were manageable and led to no discontinuation of *** proportion score of PD-L1,peripheral blood high-density lipoprotein cholesterol,and apolipoprotein A-l correlated with good response,while PD-1 on tumor infiltrating lymphocytes and peripheral Treg cells with poor response to pegaspargase plus sintilimab *** conclusion,the chemo-free regimen pegaspargase plus sintilimab was effective and safe in newly diagnosed,advanced stage *** lipid profle and immunosuppressive signature contributed to treatment resistance,providing an alternative therapeutic approach dual targeting fatty acid metabolism and CTLA-4 in NKTCL.

关键词： killer metabolism lymphoma

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petrogenesis of Early Cretaceous Pandian high-Mg diorites from the eastern North China Craton within an intracontinental setting:Implications for the skarn Fe mineralization

引用

Journal of Earth Science 2024年

作者： Si-Yuan Li chao fu Qi-Wei Feng Xiao-Bo Zhao Zhi-Cai Dang Kang-Kang Xu Ming-Bo Gao Ji-Lei Gao Zhuang Duan Ming Ma Tianjin Center China Geological Survey (North China Center for Geoscience Innovation) Shandong Engineering Research Center of High-Grade Iron Deposits Exploration and Exploitation China University of Geosciences (Beijing) No.1 Institute of Geology and Mineral Resources of Shandong Province Geological Exploration Institute of Shandong Zhengyuan China Metallurgical Geology Bureau Shandong Provincial Bureau of Geology & Mineral Resources Institute of Geophysical and Geochemical Exploration Chinese Academy of Geological Sciences

High-magnesium andesitic rocks （HMAs） were initially interpreted to have formed via interaction of slab melt with mantle in arc ***,high-magnesium diorites （HMDs,analogs of HMAs）have been recognized can be formed in intracontinental *** of the HMDs producedsignificant Fe skarn *** genesis of HMDs and how they earn high Fe mineralization fertilities remain *** Pandian HMDs,located in Luxi Block,eastern North China Craton（NCC）,formed in continental interior and show a close spatiotemporal and genetic relationship to Fe skarn *** contribution carried out a comprehensive geochemical study on the Pandian HMDs to constrain the genesis of HMDs and further shed light on the key factors leading to their high Feskarn mineralization *** rocks show high Mg#values （55–80）,andesitic compositions （SiO2:55.3–66.2 wt%）,and arc-like *** Pandian HMDs possess (87Sr/86Sr)iof0.70720–0.70737,εNd（t） values of-11.8–-12.6,(206Pb/204Pb)iof 17.3706–17.4575,(207Pb/204Pb)iof15.3945–15.4440,and (208Pb/204Pb)iof 36.6606–*** notably distinct geochemicalcharacteristics between the Pandian HMDs and ancient lower crust in the NCC make it unlikely that the Pandian HMDs were sourced from the ***,The chemical characteristics of Pandian HMDs are akin to the proximal and contemporaneous mantle-derived Ji’nan *** presentresults,combined with geological analysis,reveal that Pandian HMDs were most likely primarily derived from an ancient sub-continental lithospheric mantle （SCLM） experienced metasomatism related to the subducted Paleo-Pacific slab-released *** higher La/Sm and Hf/Sm ratios and more enriched radiogenic Sr-Pb isotopes of Pandian HMDs relative to Ji’nan gabbro indicate crustalmaterial involvement during magma *** of crustal material assimilation,based on Sr-Nd isotopes,suggests parental melts of the Pandian HMDs assimilated about 20%Archean TTG gneisses and 60%Ordovicia

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

波转子的驱动力形成机理数值模拟研究

引用

工程热物理学报 2024年第3期45卷 725-732页

作者：产世宁陈叶宇李凤超付超北京航空航天大学宁波创新研究院先进飞行器与空天动力创新研究中心宁波315800 中国航空发动机研究院北京101304 北京航空航天大学航空发动机研究院北京102206

自旋波转子用气流的驱动力维持转子旋转,能够显著简化波转子发动机系统结构、提高可靠性。通过数值模拟方法研究不同几何通道内部流动现象对切向驱动力的影响,解释波转子的驱动力形成机理。结果表明:弯曲几何通道中的激波/膨胀波在传播... 详细信息

自旋波转子用气流的驱动力维持转子旋转,能够显著简化波转子发动机系统结构、提高可靠性。通过数值模拟方法研究不同几何通道内部流动现象对切向驱动力的影响,解释波转子的驱动力形成机理。结果表明:弯曲几何通道中的激波/膨胀波在传播过程中,波面发生倾斜,导致每个通道上下壁面间存在压差,多个通道的正向压差累积最终形成正向驱动力,实现波转子自旋。

关键词：自旋波转子驱动力弯曲通道数值模拟

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

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：