检索结果-南通市图书馆

Accurate simulations of pure-viscoacoustic wave propagation in tilted transversely isotropic media

Petroleum Science 2024年第2期21卷 866-884页

作者： Qiang Mao ji.n-Ping Huang Xin-Ru Mu ji.Dong Yang Yu-ji.n zhang Geosciences Department China University of Petroleum(East China)Qingdao266580ShandongChina Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao266207ShandongChina

Forward modeling of seismic wave propagation is crucial for the realization of reverse time migration(RTM) and full waveform inversion(FWI) in attenuating transversely isotropic media. To describe the attenuation and anisotropy properties of subsurface media, the pure-viscoacoustic anisotropic wave equations are established for wavefield simulations, because they can provide clear and stable wavefields. However, due to the use of several approximations in deriving the wave equation and the introduction of a fractional Laplacian approximation in solving the derived equation, the wavefields simulated by the previous pure-viscoacoustic tilted transversely isotropic(TTI) wave equations has low accuracy. To accurately simulate wavefields in media with velocity anisotropy and attenuation anisotropy, we first derive a new pure-viscoacoustic TTI wave equation from the exact complex-valued dispersion formula in viscoelastic vertical transversely isotropic(VTI) media. Then, we present the hybrid finite-difference and low-rank decomposition(HFDLRD) method to accurately solve our proposed pure-viscoacoustic TTI wave equation. Theoretical analysis and numerical examples suggest that our pure-viscoacoustic TTI wave equation has higher accuracy than previous pure-viscoacoustic TTI wave equations in describing q P-wave kinematic and attenuation characteristics. Additionally, the numerical experiment in a simple two-layer model shows that the HFDLRD technique outperforms the hybrid finite-difference and pseudo-spectral(HFDPS) method in terms of accuracy of wavefield modeling.

关键词： Pure-viscoacoustic TTI wave equation Attenuation anisotropy Seismic modeling Low-rank decomposition method

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

Enhanced thermoelectric and mechanical properties of Bi_(0.5)Sb_(1.5)Te_(3) alloy with dispersed yttrium oxide ceramic nanoparticles

引用

Rare Metals 2024年第4期43卷 1758-1768页

作者： Cun-Cheng Li Ming-Wei zhang ji.Wu Xin Lei Wei Wen-Yu Zhao School of Materials Science and Engineering Shandong University of TechnologyZibo255000China School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore639798Singapore State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan430070China

Reducing thermal conductivity while avoiding adverse interfacial reactions during sintering is crucial for improving the thermoelectric performance of Bi_(2)Te_(3)based *** ceramic nanoparticles are good candidates for achieving this *** this study,we designed and prepared a series of p-type Bi_(0.5)Sb_(1.5)Te_(3)nanocomposites decorated with Y_(2)O_(3)ceramic nanoparticles via ball-milling dispersion and spark-plasma *** to the chemical stability of the ceramics,no traces of atomic doping or interfacial reactions were *** measurements revealed that the Y_(2)O_(3)nanoparticles distributed along the grain boundaries acted as energy-dependent carrier-filtering centers to improve the scattering parameter and Seebeck coefficient,contributing to the elevated power factor even with a decreased electrical ***,the incorporated Y_(2)O_(3)nanoparticles and various defect structures they induced effectively strengthened the phonon scattering and suppressed the lattice thermal ***,a peak figure of merit(ZT)of 1.23 at 313 K was achieved for 0.4%Y_(2)O_(3)/Bi_(0.5)Sb_(1.5)Te_(3),which is 13%higher than that of the *** addition,the Vickers hardness of the composite material was 35%higher than that of the *** study demonstrates the effectiveness of ceramic nanoparticles in synergistic ally improving the thermoelectric and mechanical properties,which may be further extended to other thermoelectric systems.

关键词： Bi_(0.5)Sb_(1.5)Te_3 alloy Y_(2)O_(3) ceramic nanoparticles Microstructures Thermoelectric performance Mechanical properties

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

Development review and the prospect of oil shale in-situ catalysis conversion technology

引用

Petroleum Science 2024年第2期21卷 1385-1395页

作者： Li Wang Chen-Hao Gao Rui-Ying Xiong Xiao-Jun zhang ji.Xiang Guo The Unconventional Oil and Gas Institute China University of Petroleum-BeijingBeijing102200China

As an unconventional resource, oil shale possesses abundant reserves and significant potential for industrial applications. The rational and efficient development of oil shale resources holds immense importance in reducing national energy demand. In-situ catalytic technology, characterized by its high efficiency, low pollution, and minimal energy consumption, represents a key direction for future oil shale development. This paper provides a comprehensive review of research progress in in-situ oil shale mining technology, oil shale pyrolysis catalysts, the pyrolysis mechanism of kerogen, and the compatibility of different heating processes and catalysts. Furthermore, the paper proposes future research directions and prospects for oil shale in-situ catalytic technology, including reservoir modification, highefficiency catalyst synthesis, injection processes, and high-efficiency heating technology. These insights serve as valuable technical references for the advancement of oil shale in-situ catalytic technology.

关键词： Oil shale In-situ catalytic technology Pyrolysis catalyst Kerogen pyrolysis mechanism

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

Retrieval of Antarctic sea ice freeboard and thickness from HY-2B satellite altimeter data

引用

Acta Oceanologica Sinica 2024年第3期43卷 87-101页

作者： Yizhuo Chen Xiaoping Pang Qing ji.Zhongnan Yan Zeyu Liang Chenlei zhang Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhan 430079China Key Laboratory of Polar Surveying and Mapping Science Ministry of Natural ResourcesWuhan 430079China Key Laboratory of Polar Environment Monitoring and Public Governance Ministry of EducationWuhan 430079China 4 School of Geography and Tourism Anhui Normal UniversityWuhu 241002China

Antarctic sea ice is an important part of the Earth’s atmospheric system,and satellite remote sensing is an important technology for observing Antarctic sea *** Chinese Haiyang-2B(HY-2B)satellite altimeter data could be used to estimate sea ice freeboard and provide alternative Antarctic sea ice thickness information with a high precision and long time series,as other radar altimetry satellites can,needs further *** paper proposed an algorithm to discriminate leads and then retrieve sea ice freeboard and thickness from HY-2B radar altimeter *** first collected the Moderate-resolution Imaging Spectroradiometer ice surface temperature(IST)product from the National Aeronautics and Space Administration to extract leads from the Antarctic waters and verified their accuracy through Sentinel-1 Synthetic Aperture Radar ***,a surface classification decision tree was generated for HY-2B satellite altimeter measurements of the Antarctic waters to extract leads and calculate local sea surface *** then estimated the Antarctic sea ice freeboard and thickness based on local sea surface heights and the static equilibrium ***,the retrieved HY-2B Antarctic sea ice thickness was compared with the CryoSat-2 sea ice thickness and the Antarctic Sea Ice Processes and Climate(ASPeCt)ship-based observed sea ice *** results indicate that our classification decision tree constructed for HY-2B satellite altimeter measurements was reasonable,and the root mean square error of the obtained sea ice thickness compared to the ship measurements was 0.62 *** proposed sea ice thickness algorithm for the HY-2B radar satellite fills a gap in this application domain for the HY-series satellites and can be a complement to existing Antarctic sea ice thickness products;this algorithm could provide long-time-series and large-scale sea ice thickness data that contribute to research on global climate change.

关键词： HY-2B satellite altimeter classification decision tree sea ice freeboard and thickness Antarctic waters

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

Loyal wingman task execution for future aerial combat:A hierarchical prior-based reinforcement learning approach

引用

Chinese Journal of Aeronautics 2024年第5期37卷 462-481页

作者： ji.ndong zhang Dinghan WANG Qiming YANG Zhuoyong SHI Longmeng ji.Guoqing SHI Yong WU School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710129China

In modern Beyond-Visual-Range(BVR)aerial combat,unmanned loyal wingmen are pivotal,yet their autonomous capabilities are *** study introduces an advanced control algorithm based on hierarchical reinforcement learning to enhance these capabilities for critical missions like target search,positioning,and relay *** on a dual-layer model,the algorithm’s lower layer manages basic aircraft maneuvers for optimal flight,while the upper layer processes battlefield dynamics,issuing precise navigational *** approach enables accurate navigation and effective reconnaissance for lead ***,our Hierarchical Prior-augmented Proximal Policy Optimization(HPE-PPO)algorithm employs a prior-based training,prior-free execution method,accelerating target positioning training and ensuring robust target *** paper also improves missile relay guidance and promotes the effective *** integrating this system with a human-piloted lead aircraft,this paper proposes a potent solution for cooperative aerial *** experiments demonstrate enhanced survivability and efficiency of loyal wingmen,marking a significant contribution to Unmanned Aerial Vehicles(UAV)formation control *** advancement is poised to drive substantial interest and progress in the related technological fields.

关键词： Beyond-visual-range Loyal wingmen Hierarchical prior-augmented proximal policy optimization Unmanned aerial vehicles Warfare

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

Towards carbon neutrality of calcium carbide-based acetylene production with sustainable biomass resources

引用

Green Energy & Environment 2024年第6期9卷 1068-1078页

作者： Peng ji.ng Guanhan Zhao Hao zhang Tuo ji.Liwen Mu Xiaohua Lu ji.hua Zhu State Key Laboratory of Materials-oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing211816China

Acetylene is produced from the reaction between calcium carbide(CaC_(2))and water,while the production of CaC_(2) generates significant amount of carbon dioxide not only because it is an energy-intensive process but also the raw material for CaC_(2) synthesis is from ***,a comprehensive biomass-to-acetylene process was constructed that integrated several units including biomass pyrolysis,oxygen-thermal CaC_(2) fabrication and calcium *** comparison,a coal-to-acetylene process was also established by using coal as *** carbon efficiency,energy efficiency and environmental impacts of the bio-based calcium carbide acetylene(BCCA)and coal-based calcium carbide acetylene(CCCA)processes were systematically ***,the environmental impacts were further evaluated by applying thermal integration at system level and energy substitution in CaC_(2) *** though the BCCA process showed lower carbon efficiency and energy efficiency than that of the CCCA process,life cycle assessment demonstrated the BCCA(1.873 kgCO_(2eq) kg-prod^(-1))a lower carbon footprint process which is 0.366 kgCO_(2eq) kg-prod^(-1) lower compared to the CCCA *** sustainable energy(biomass power)substitution in CaC_(2) furnace,an even lower GWP value of 1.377 kgCO_(2eq) kg-prod^(-1) can be achieved in BCCA *** work performed a systematic analysis on integrating biomass into industrial acetylene production,and revealed the positive role of biomass as raw material(carbon)and energy supplier.

关键词： Biomass pyrolysis CO_(2)mitigation Calcium carbide Acetylene Calcium loop

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

Biogenesis of Rab14-positive Endosome Buds at Golgi-endosome Contacts by the RhoBTB3-SHIP164-Vps26B Complex

引用

Current Medical Science 2024年第4期44卷 864-866页

作者： ji.g-ru WANG Jun-yao zhang Wei-Ke ji Department of Biochemistry and Molecular Biology School of Basic MedicineTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Cell Architecture Research Center Huazhong University of Science and TechnologyWuhan430030China State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Diseases Huazhong University of Science and TechnologyWuhan430030China Shenzhen Bay Laboratory Shenzhen518132China

As one of the basic processes of cellular activity,endocytosis sorting determines the fate of many proteins on the endosomal membranes,thus affecting a variety of important cellular processes,such as nutrient uptake,c... 详细信息

关键词： homeostasis endo sorting

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

Multi-scenario land use prediction and layout optimization in Nanji.g Metropolitan Area based on the PLUS model

引用

Journal of Geographical Sciences 2024年第7期34卷 1415-1436页

作者： CAO ji.CAO Weidong CAO Yuhong WANG Xuewei zhang Yizhen MA ji.ji School of Geography and Tourism Anhui Normal UniversityWuhuAnhui241002China School of Ecology and Environment Anhui Normal UniversityWuhuAnhui241002China

The metropolitan area is a crucial spatial element in promoting new urbanization in *** possesses theoretical and empirical value in the determination of the evolutionary patterns and development trends necessary for regional integration and high-quality *** study focused on Nanji.g Metropolitan Area,the first national metropolitan area in China,and established three development scenarios by combining ecological–economic spatial conflict(EESC)zones and national key ecological functional *** scenarios simulate the spatial distribution of future land use and land cover change(LUCC)using the development zone planning function of the patch generation land use simulation(PLUS)*** results show that:(1)Between 2000 and 2020,the most prominent characteristics of land use change were largely the massive expansion of built-up land and the significant decline of farmland,while changes in the area of ecological land were less evident.(2)EESC areas experienced significant changes over the past 20 years,but the overall level of conflict was *** land was the main land use type in the lowest-conflict area,while built-up land was the main land use type in the highest-conflict area.(3)From 2030 to 2050,further expansion of built-up areas is expected,with continued decrease of *** regulation of these land use changes can be achieved through different development zone *** economic development scenario had the largest built-up land area,while the ecological protection scenario had the largest farmland *** study simulates the spatial pattern changes in the metropolitan area based on spatial conflict patterns and national main functional area planning process,providing a scientific reference for future spatial planning and management.

关键词： land use change spatial conflict patch-generating simulation land use prediction Nanji.g Metropolitan Area

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

Overhead-free Noise-tolerant Federated Learning: A New Baseline

引用

Machine Intelligence Research 2024年第3期21卷 526-537页

作者： Shiyi Lin Deming Zhai Feilong zhang Junjun ji.ng Xianming Liu Xiangyang ji Department of Computer Science and Technology Harbin Institute of TechnologyHarbin150000China Department of Automation Tsinghua UniversityBeijing100084China

Federated learning (FL) is a promising decentralized machine learning approach that enables multiple distributed clients to train a model jointly while keeping their data private. However, in real-world scenarios, the supervised training data stored in local clients inevitably suffer from imperfect annotations, resulting in subjective, inconsistent and biased labels. These noisy labels can harm the collaborative aggregation process of FL by inducing inconsistent decision boundaries. Unfortunately, few attempts have been made towards noise-tolerant federated learning, with most of them relying on the strategy of transmitting overhead messages to assist noisy labels detection and correction, which increases the communication burden as well as privacy risks. In this paper, we propose a simple yet effective method for noise-tolerant FL based on the well-established co-training framework. Our method leverages the inherent discrepancy in the learning ability of the local and global models in FL, which can be regarded as two complementary views. By iteratively exchanging samples with their high confident predictions, the two models “teach each other” to suppress the influence of noisy labels. The proposed scheme enjoys the benefit of overhead cost-free and can serve as a robust and efficient baseline for noise-tolerant federated learning. Experimental results demonstrate that our method outperforms existing approaches, highlighting the superiority of our method.

关键词： Federated learning noise-label learning privacy-preserving machine learning edge intelligence distributed machine learning

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

Structural features in the mid-southern section of the Kyushu–Palau Ridge based on satellite altimetry gravity anomaly

引用

Acta Oceanologica Sinica 2024年第4期43卷 50-60页

作者： Feifei zhang Dingding Wang Xiaolin ji.Fanghui Hou Yuan Yang Wanyin Wang School of Geological Engineering and Geomatics Chang’an UniversityXi’an 710054China Qingdao Institute of Marine Geology China Geological SurveyQingdao 266071China Information and Navigation College Air Force Engineering UniversityXi’an 710077China National Engineering Research Center of Offshore Oil and Gas Exploration Beijing 100028China Key Laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of SciencesQingdao 266071China

The Kyushu–Palau Ridge(KPR),an anti-S-shaped submarine highland at the center of the Philippine Sea Plate(PSP),is considered the residual arc of the Izu–Bonin–Mariana Island Arc,which retains key information about the cessation of the Western Philippine Basin(WPB)expansion and the Parece Vela Basin(PVB)***,using the new generation of satellite altimetry gravity data,high-precision seafloor topography data,and newly acquired ship-borne gravity data,the topographic and gravity characteristics of the KPR mid-southern section and adjacent region are *** distribution characteristics of the faults were delineated using the normalized vertical derivative–total horizontal derivative method(NVDR-THDR)and the minimum curvature potential field separation *** Moho depth and crustal thickness were inverted using the rapid inversion method for a double-interface model with depth *** on these results,the crust structure features in the KPR mid-southern section,and the“triangular”structure geological significance where the KPR and Central Basin Rift(CBR)of the WPB intersect are *** KPR crustal thickness is approximately 6–16 km,with a distinct discontinuity that is slightly thicker than the normal oceanic *** KPR mid-southern section crust structure was divided into four segments(S1–S4)from north to south,formed by the CBR eastward extension joint action and clockwise rotation of the PVB expansion axis and the Mindanao fault zone blocking effect.

关键词： structural features satellite altimetry gravity data Kyushu-Palau Ridge Central Basin Rift faults Moho depth

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：