检索结果-内蒙古大学图书馆

25th Conference on Economics and Computation, EC 2024

作者： Lu, Pinyan Wan, Zongqi Zhang, Jialin Shanghai University of Finance and Economics Shanghai China SKLP Institute of Computing Technology Chinese Academy of Sciences Beijing China Key Laboratory of Interdisciplinary Research of Computation and Economics Shanghai University of Finance and Economics Ministry of Education China School of Computer Science and Technology University of Chinese Academy of Sciences China

ISBN: (纸本)9798400707049

The competitive auction was first proposed by Goldberg, Hartline, and Wright. In their paper [Goldberg et al., 2001], they introduce the competitive analysis framework of online algorithm design into the traditional revenue-maximizing auction design problem. While the competitive analysis framework only cares about the worst-case bound, a growing body of work in the online algorithm community studies the learning-augmented framework. In this framework, designers are allowed to leverage imperfect machine-learned predictions of unknown information and pursue better theoretical guarantees when the prediction is accurate(consistency). Meanwhile, designers also need to maintain a nearly-optimal worst-case ratio(robustness). In this work, we revisit the competitive auctions in the learning-augmented setting. We leverage the imperfect predictions of the private value of the bidders and design the learning-augmented mechanisms for several competitive auctions with different constraints, including: digital good auctions, limited-supply auctions, and general downward-closed permutation environments. We also design the learning-augmented mechanism for online auctions. For all these auction environments, our mechanisms enjoy 1-consistency against the strongest benchmark OPT. In contrast, it is impossible to achieve O(1)-competitiveness against OPT without predictions. At the same time, our mechanisms also maintain the O(1)-robustness against all benchmarks considered in the traditional competitive analysis, including F (2), maxV, and EFO(2). Considering the possible inaccuracy of the predictions, we provide a reduction that transforms our learning-augmented mechanisms into an error-tolerant version, which enables the learning-augmented mechanism to ensure satisfactory revenue in scenarios where the prediction error is moderate. We also prove a 3 robustness ratio lower bound for mechanisms with perfect consistency. The lower bound is strictly greater than the optimal 2.42 compet

关键词： Contrastive Learning

来源：评论

学校读者我要写书评

暂无评论

Design and development of the additively manufactured Zn-Li scaffolds for posterolateral lumbar fusion

引用

材料科学技术（英文版） 2025年第12期215卷 180-191页

作者： Yu Qin Chunhao Yu Peng Wang Hongtao Yang Aobo Liu Shuhan Wang Zhenquan Shen Senju Ma Yongcan Huang Binsheng Yu Peng Wen Yufeng Zheng Shenzhen Key Laboratory of Spine Surgery Department of Spine SurgeryPeking University Shenzhen HospitalShenzhen Peking University-The Hong Kong University of Science and Technology Medical CenterShenzhen 518036China School of Materials Science and Engineering Peking UniversityBeijing 100871China School of Materials Science and Engineering Peking UniversityBeijing 100871China Clinical College Peking University Shenzhen HospitalAnhui Medical UniversityShenzhen 518036China The Fifth Clinical Medical College Anhui Medical UniversityHefei 230032China School of Engineering Medicine Beihang UniversityBeijing 100191China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Shenzhen Institute for Drug Control(Shenzhen Testing center of Medical Devices) Shenzhen 518057China Shenzhen Key Laboratory of Spine Surgery Department of Spine SurgeryPeking University Shenzhen HospitalShenzhen Peking University-The Hong Kong University of Science and Technology Medical CenterShenzhen 518036China

Spinal fusion is a commonly used technique to treat acute and chronic spinal diseases by fusion of the adjacent vertebrae,aiming at achieving stability and eliminating the mobility of the objective *** bone autografts and allografts have been conventionally used for spinal fusion,limitations persist in achieving optimization of both good osteoinductive capacity and mechanical *** this study,additively manufactured Zn-Li scaffolds were developed and evaluated for their potential in spinal ***,three scaffold structures(BCC,Diamond,and Gyroid)were designed and verified in *** to the smooth transition surfaces and uniform degradation behavior,the Gyroid Zn-Li scaffold demon-strated mechanical integrity during degradation and enhanced cellular proliferation compared to the other two ***,Zn-Li scaffolds(Gyroid)were selected for posterolateral lumbar fu-sion(L4/L5)in *** 12 weeks of implantation,the Zn-Li scaffolds demonstrated a moder-ate biodegradation rate and satisfactory *** to bone allografts,the Zn-Li scaf-folds significantly improved osseointegration adjacent to the transverse processes,which led to enhanced segmental stability of the fused vertebrae post posterolateral lumbar ***,the results show that the biodegradable Zn-Li scaffold holds substantial potential as the next-generation graft for spinal fusion.

关键词： Zn alloy Additive manufacturing Spinal fusion Biodegradable metals Osseointegration

来源：评论

学校读者我要写书评

暂无评论

The AaBBX21–AaHY5 module mediates light-regulated artemisinin biosynthesis in Artemisia annua L.

引用

Journal of Integrative Plant Biology 2024年第8期66卷 1735-1751页

作者： Weizhi He Hang Liu Zhangkuanyu Wu Qing Miao Xinyi Hu Xin Yan Hangyu Wen Yaojie Zhang Xueqing Fu Li Ren Kexuan Tang Ling Li Frontiers Science Center for Transformative Molecules Joint International ResearchLaboratory of Metabolic and Developmental SciencesKey Laboratory of Urban Agriculture(South)Ministry of AgriculturePlant Biotechnology Research CenterFudan-SJTU-Nottingham Plant Biotechnology R&D CenterSchool of Agriculture and BiologyShanghai Jiao Tong UniversityShanghai 200240China Institute for Agri-Food Standards and Testing Technology Shanghai Academy of Agricultural SciencesShanghai 201403China

The sesquiterpene lactone artemisinin is an important anti-malarial component produced by the glandular secretory trichomes of sweet wormwood(Artemisia annua L.).Light was previously shown to promote artemisinin production,but the underlying regulatory mechanism remains *** this study,we demonstrate that ELONGATED HYPOCOTYL5(HY5),a central transcription factor in the light signaling pathway,cannot promote artemisinin biosynthesis on its own,as the binding of AaHY5 to the promoters of artemisinin biosynthetic genes failed to activate their *** analysis and yeast two-hybrid screening revealed the B-box transcription factor AaBBX21 as a potential interactor with ***21 showed a trichome-specific expression ***,the AaBBX21–AaHY5 complex cooperatively activated transcription from the promoters of the downstream genes AaGSW1,AaMYB108,and AaORA,encoding positive regulators of artemisinin ***,AaHY5 and AaBBX21 physically interacted with the *** E3 ubiquitin ligase CONSTITUTIVELY PHOTOMORPHOGENIC 1(COP1).In the dark,AaCOP1 decreased the accumulation of AaHY5 and AaBBX21 and repressed the activation of genes downstream of the AaHY5–AaBBX21 complex,explaining the enhanced production of artemisinin upon light *** study provides insights into the central regulatory mechanism by which light governs terpenoid biosynthesis in the plant kingdom.

关键词： AaBBX21 AaHY5 AaCOP1 Artemisia annua L. artemisinin biosynthesis light

来源：评论

学校读者我要写书评

暂无评论

Modeling and Simulation analysis of Operation Characteristics of Supplemental Fired Absorption Heat Exchanger 2

Modeling and Simulation Analysis of Operation Characteristic...

引用

2023 2nd International Conference on Power System and Energy technology, ICPSET 2023

作者： Lian, Xueli Zhang, Chenghu Di, Yanqiang China Academy of Building Research Beijing China School of Architecture Harbin Institute of Technology Harbin China Key Laboratory of Cold Region Urban and Rural Human Settlement Environment Science and Technology Harbin Institute of Technology Ministry of Industry and Information Technology Harbin China

Based on a general single-segment absorption heat exchange unit, a series complementary lithium bromide absorption heat exchange unit was constructed by adding a direct combustion unit, which can achieve a lower backwater temperature on the primary side, thereby increasing the heating capacity. Based on the analysis of the thermodynamic cycle and heat-transfer process, the mathematical model was built and solved using an iterative numerical method. Based on satisfying heating load, the impact of the temperature of supply water on the primary side on the operating characteristics of the unit under different load conditions was quantitatively analyzed. The result shows a negative correlation between backwater temperature on the primary side and supply water temperature on the primary side when other parameters are unchanged. If the supply water temperature on the primary side remains unchanged, the temperature of the backwater on the primary side decreases with the increase of heating load, and the ratio of heat exchange of plate heat exchange unit to total heat exchange decreases with the increase of heating load. For example, when the supply water temperature is 120°C, the proportion of water-water plate heat exchange capacity to total corresponding to 100% heat load, 90% heat load, and 75% heat load is 0.465, 0.580, and 0.772, respectively. © Published under licence by IOP Publishing Ltd.

关键词： Thermal load

来源：评论

学校读者我要写书评

暂无评论

Age-Period-Cohort analysis on Long-Term Mortality Trend of Genitourinary Diseases—China,1987–2021

引用

China CDC weekly 2023年第51期5卷 1135-1139页

作者： Panliang Zhong Chen Chen Yunduo Liu Xinyue Wei Feipeng Cui Shuai Guo Yaohua Tian School of Population Medicine and Public Health Chinese Academy of Medical Sciences/Peking Union Medical CollegeBeijingChina Department of Aging and Health School of Population Medicine and Public HealthChinese Academy of Medical Sciences/Peking Union Medical CollegeBeijingChina APEC Health Science Academy(HeSAY) Peking University/Institute of Population ResearchPeking UniversityBeijingChina School of Public Health Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan CityHubei ProvinceChina Ministry of Education Key Laboratory of Environment and Health and State Key Laboratory of Environmental Health(Incubating)School of Public HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhan CityHubei ProvinceChina.

What is already known about this topic?There has been a lack of attention to genitourinary diseases for an extended period,resulting in limited research on the mortality trends of genitourinary diseases in *** is added by this report?This study examines the long-term trend of genitourinary diseases'mortality across Chinese individuals of all genders and in various urban and rural ***,it investigates the impact of age-period-cohort effects on this *** are the implications for public health practice?It is imperative to address genitourinary diseases,particularly among vulnerable populations such as rural older *** should prioritize these individuals by providing necessary policy interventions and healthcare support.

关键词： urinary mortality diseases

来源：评论

学校读者我要写书评

暂无评论

Effect of Different Scanning Modes and Heat Treatment on Microstructure and Mechanical Properties of GH4169 Manufactured by Selective Laser Melting 5th

Effect of Different Scanning Modes and Heat Treatment on Mic...

引用

5th China Aviation science and technology Conference, 2021

作者： Zhou, Jingyi Wei, Zhenwei Tang, Siyi Zhao, Wenxia Guo, Shaoqing Wang, Jian Zhao, Zijun AECC Beijing Institute of Aeronautical Materials Beijing100095 China Beijing Key Laboratory of Aeronautical Materials Testing and Evaluation Beijing100095 China Key Laboratory of Aeronautical Materials Testing and Evaluation Aero Engine Corporation of China Beijing100095 China Aviation Key Laboratory of Science and Technology on Materials Testing and Evaluation Beijing100095 China Aero Engine Corporation of China Beijing100097 China

ISBN: (纸本)9789811674228

GH4169 superalloy was prepared by selective laser melting technique. The samples were obtained by scanning in a single direction per layer and scanning in a 90° direction per layer, respectively. The microstructure and precipitated phase were compared and analyzed by OM, SEM and EDS to investigate the non-equilibrium microstructure characteristics and the influence mechanism on mechanical properties of laser additive manufacturing materials of GH4169 under three heat treatment systems. The results show that in the X direction of laser scanning deposition, the tensile strength at room temperature of the material with the same scanning direction of each layer is 4.5% higher than that of the material with the scanning direction of 90°, and the reduction of area is 75.6% higher. After solution and aging treatment, δ phase was precipitated and Laves phase was partially dissolved, but the element segregation in the remelting zone between the cladding layers was not completely eliminated. Homogenization treatment at 1050 ℃ for 1h promotes uniform distribution of segregation elements in cladding layer, remelting layer and dendrite. After homogenization treatment at 1100 ℃ for 1h, Laves phase was fully redissolved, and δ phase and strengthening phase γ ‘ were precipitated again after solution and aging. After heat treatment, the tensile strength at room temperature of the samples prepared by the two laser scanning methods is basically the same in the X direction. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Scanning

来源：评论

学校读者我要写书评

暂无评论

Mechanical(compressive)form of driving force triggers the phase transformation fromβtoω&α”phases in metastableβphase-field Ti-5553 alloy

引用

Journal of Materials science & technology 2021年第19期78卷 238-246页

作者： Tayyeb Ali Lin Wang Xingwang Cheng Huanwu Cheng Ying Yang Anjin Liu Xuefeng Xu Zhe Zhou Zixuan Ning Ziqi Xu Xinhua Min School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Science and Technology on Materials Under Shock and Impact Beijing 100081China Beijing Center for Physical and Chemical Analysis Beijing 100089China Baosteel Special Materials CO.LTD Shanghai China

Most of the structural alloys’applications are under static,dynamic,and cyclic forms of ***-5553 alloy in the beta phase field is being investigated to confirm the mechanism of deformation and phase transformation upon quasi-static and dynamic *** Ti-5553 alloy was heat-treated at 900℃ (almost 50℃ above beta transus temperature)for one hour of soaking time followed by air quenching to achieve a fullyβphase *** that,Dynamic compression(DC)by Split Hopkinson Pressure Bar(SHPB)and Quasi-static compression(QSC)were performed at a strain rate of~10^3)/s and 10^(-3)/s,*** specimens were thoroughly examined by using different tools,such as an Optical microscope(OM),Scanning electron microscope(SEM),High-resolution transmission electron microscope(HRTEM),and Electron backscatter diffraction(EBSD)to get the reliable data for justification of logical *** is found that the dominating mode of deformation was dislocation slip along with twinning({332}<113>)to some extent in both of QSC and DC,but sliding&spalling of the grain boundary is observed more in the ***-induced phase transformation,i.e.,βtoα"andβtoω,took place in the grains saturated with dislocation slips,where the former transformation occurred simultaneously with{332}<113>twinning,whileβtoωtransformation was completed when a set of two adjacent(110)_(β)planes covered±1/6th of the total separation distance between two(next to each other)(111)_(β)planes,by equal but opposite shear in(111)_(β)direction,and it caused 3%shrinkage of two closed packed(110)_(β)planes after transformation.

关键词： Quasi-static&dynamic compression Phase transformation Deformation structures Dislocation slips Grain boundary sliding

来源：评论

学校读者我要写书评

暂无评论

Study on Prognostics and Health Management of Fluid Loop System for Space Application 14

Study on Prognostics and Health Management of Fluid Loop Sys...

引用

14th International Conference on Damage Assessment of Structures, DAMAS 2021

作者： Cao, Zhi Zhang, Junhua Li, Zhenxiang Zhao, Xin Guo, Dong Fu, Hongyong School of Computer Science And Technology University of Chinese Academy of Sciences Beijing China Key Laboratory of Space Utilization Technology And Engineering Center For Space Utilization Chinese Academy of Sciences Beijing China

Prognostics and Health Management (PHM) is an important technical means to realize condition-based maintenance of complex systems. As a complex space application engineering, the space application fluid loop system has the requirements of high safety, high reliability and long life. Therefore, this paper adopts PHM technology to comprehensively study the space application fluid loop system from two aspects of architecture and key technology respectively. Firstly, this paper introduces the current status of health management of fluid loop system for space application and the problems to be solved urgently. Secondly, the PHM system architecture and key technologies such as condition monitoring, health assessment, fault diagnosis, fault prediction and health management are described, and the PHM system research scheme of fluid loop for space application is established. Finally, a case study is carried out by taking the fluid loop main engine of the core power equipment as an example. The analysis results show that the PHM technology can effectively reduce the system failure rate, improve the system safety and reliability, and provide a strong guarantee for the long-term on-orbit operation of the system. © Published under licence by IOP Publishing Ltd.

关键词： Systems engineering

来源：评论

学校读者我要写书评

暂无评论

An Improved HVQ Algorithm for Compression and Rendering of Space Environment Volume Data with Multi-correlated Variables

引用

空间科学学报 2023年第4期43卷 780-785页

作者： BAO Lili CAI Yanxia WANG Rui ZOU Yenan SHI Liqin State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190 Key Laboratory of Science and Technology on Environmental Space Situation Awareness Chinese Academy of SciencesBeijing 100190 University of Chinese Academy of Sciences Beijing 100049

Volume visualization can not only illustrate overall distribution but also inner structure and it is an important approach for space environment *** environment simulation can produce several correlated variables at the same ***,existing compressed volume rendering methods only consider reducing the redundant information in a single volume of a specific variable,not dealing with the redundant information among these *** space environment volume data with multi-correlated variables,based on the HVQ-1d method we propose a further improved HVQ method by compositing variable-specific levels to reduce the redundant information among these *** volume data associated with each variable is divided into disjoint blocks of size 43 *** blocks are represented as two levels,a mean level and a detail *** variable-specific mean levels and detail levels are combined respectively to form a larger global mean level and a larger global detail *** both global levels,a splitting based on a principal component analysis is applied to compute initial ***,LBG algorithm is conducted for codebook refinement and *** further take advantage of progressive rendering based on GPU for real-time interactive *** method has been tested along with HVQ and HVQ-1d on high-energy proton flux volume data,including>5,>10,>30 and>50 MeV integrated proton *** results of our experiments prove that the method proposed in this paper pays the least cost of quality at compression,achieves a higher decompression and rendering speed compared with HVQ and provides satisficed fidelity while ensuring interactive rendering speed.

关键词： Compressed volume rendering Multi-correlated variables Space environment Vector quantization GPU programming

来源：评论

学校读者我要写书评

暂无评论

Anomaly Detection of Industrial Control Systems Based on Transfer Learning

引用

Tsinghua science and technology 2021年第6期26卷 821-832页

作者： Weiping Wang Zhaorong Wang Zhanfan Zhou Haixia Deng Weiliang Zhao Chunyang Wang Yongzhen Guo School of Computer and Communication Engineering the Beijing Key Laboratory of Knowledge Engineering for Materials Scienceand the Institute of Artificial IntelligenceUniversity of Science and Technology BeijingBeijing 100083China Shunde Graduate School University of Science and Technology BeijingGuangzhou 528399China School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing 100083China School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China Donlinks School of Economics and Management University of Science and Technology Beijing Beijing 100083China School of Automation Beijing Institute of TechnologyBeijing 100081 China Software Testing Center Beijing 100048China.

Industrial Control Systems(ICSs)are the lifeline of a ***,the anomaly detection of ICS traffic is an important *** paper proposes a model based on a deep residual Convolution Neural Network(CNN)to prevent gradient explosion or gradient disappearance and guarantee *** developed methodology addresses two limitations:most traditional machine learning methods can only detect known network attacks and deep learning algorithms require a long time to *** utilization of transfer learning under the modification of the existing residual CNN structure guarantees the detection of unknown ***-dimensional ICS flow data are converted into two-dimensional grayscale images to take full advantage of the features of *** show that the proposed method achieves a high score and solves the time problem associated with deep learning model *** model can give reliable predictions for unknown or differently distributed abnormal data through short-term ***,the proposed model ensures the safety of ICSs and verifies the feasibility of transfer learning for ICS anomaly detection.

关键词： anomaly detection transfer learning deep learning Industrial Control System(ICS)

来源：评论

学校读者我要写书评

暂无评论

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

请选择保存的检索档案：

请选择收藏分类：

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

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

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：