检索结果-内蒙古大学图书馆

QAAS:quick accurate auto-scaling for streaming processing

Frontiers of Computer science 2024年第1期18卷 5-15页

作者： Shiyuan LIU Yunchun LI Hailong YANG Ming DUN Chen CHEN Huaitao ZHANG Wei LI State Key Laboratory of Software Development Environment Beijing 100191China School of Computer Science and Engineering Beihang UniversityBeijing 100191China School of Cyber Science and Technology Beihang UniversityBeijing 100191China School of Computer Science and Technology Xi’an Jiaotong UniversityXi’an 710049China

In recent years,the demand for real-time data processing has been increasing,and various stream processing systems have *** the amount of data input to the stream processing system fluctuates,the computing resources required by the stream processing job will also *** resources used by stream processing jobs need to be adjusted according to load changes,avoiding the waste of computing *** present,existing works adjust stream processing jobs based on the assumption that there is a linear relationship between the operator parallelism and operator resource consumption(e.g.,throughput),which makes a significant deviation when the operator parallelism *** paper proposes a nonlinear model to represent operator *** divide the operator performance into three stages,the Non-competition stage,the Non-full competition stage,and the Full competition *** our proposed performance model,given the parallelism of the operator,we can accurately predict the CPU utilization and operator *** with actual experiments,the prediction error of our model is below 5%.We also propose a quick accurate auto-scaling(QAAS)method that uses the operator performance model to implement the auto-scaling of the operator parallelism of the Flink *** to previous work,QAAS is able to maintain stable job performance under load changes,minimizing the number of job adjustments and reducing data backlogs by 50%.

关键词： stream processing performance model auto-scaling

来源：评论

学校读者我要写书评

暂无评论

EPHA2 is a novel cell surface marker of OCT4-positive undifferentiated cells during the differentiation of mouse and human pluripotent stem cells (May, szae036, 2024)

引用

STEM CELLS TRANSLATIONAL MEDICINE 2024年第9期13卷 940-940页

作者： Intoh, Atsushi Watanabe-Susaki, Kanako Kato, Taku Kiritani, Hibiki Kurisaki, Akira Division of Biological Science Nara Institute of Science and Technology Nara 630-0192 Japan. Organ Development Research Laboratory National Institute of Advanced Industrial Science and Technology (AIST) Tsukuba 305-8560 Japan.

Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) possess the intrinsic ability to differentiate into diverse cellular lineages, marking them as potent instruments in regenerative medicine. Nonetheless, the proclivity of these stem cells to generate teratomas post-transplantation presents a formidable obstacle to their therapeutic utility. In previous studies, we identified an array of cell surface proteins specifically expressed in the pluripotent state, as revealed through proteomic analysis. Here we focused on EPHA2, a protein found to be abundantly present on the surface of undifferentiated mouse ESCs and is diminished upon differentiation. Knock-down of Epha2 led to the spontaneous differentiation of mouse ESCs, underscoring a pivotal role of EPHA2 in maintaining an undifferentiated cell state. Further investigations revealed a strong correlation between EPHA2 and OCT4 expression during the differentiation of both mouse and human PSCs. Notably, removing EPHA2+ cells from mouse ESC-derived hepatic lineage reduced tumor formation after transplanting them into immune-deficient mice. Similarly, in human iPSCs, a larger proportion of EPHA2+ cells correlated with higher OCT4 expression, reflecting the pattern observed in mouse ESCs. Conclusively, EPHA2 emerges as a potential marker for selecting undifferentiated stem cells, providing a valuable method to decrease tumorigenesis risks after stem-cell transplantation in regenerative treatments.

关键词： EPHA2 cell surface marker pluripotent stem cells stem cell transplantation tumorigenesis

来源：评论

学校读者我要写书评

暂无评论

STATE OF THE ART OF CONVENTIONAL WIND TURBINES development

International Journal of Mechatronics and Applied Mechanics

引用

International Journal of Mechatronics and Applied Mechanics 2025年第19期2025卷 205-215页

作者： Popescu, Ionela-Mihaela Popescu, Valentin-Serban Vasilescu, Alexandra-Gabriela Constantin, Victor Avram, Mihai National University of Science and Technology Politehnica Bucharest Romania National Institute of Research and Development in Mechatronics and Measurement Technique Bucharest Romania

This paper aims to analyze the evolution of wind turbines in the last decade and place it in the context of environmental changes that have occurred in recent years. The use of artificial intelligence, genetic algorithms, and machine learning in the field of wind energy may increase energy production and ensures predictive maintenance of installations. Implementing AI at the level of wind turbine control systems brings benefits such as: reduced data analysis time;standardized data labeling;increased performance and reduced maintenance costs. Another method for determining the need for repairs is the use of machine learning, which can reduce downtime and extend the life of the turbine. Genetic algorithms can increase the efficiency of blade pitch and durability of vertical axis wind turbines. Analysis of system errors and multiple key parameters facilitates maintenance and reduces operating costs. These advanced control methods for both horizontal axis and vertical axis wind turbines increase efficiency, provide optimized system parameters and control designs as output. The production of wind turbine components and the reduction of carbon dioxide emissions can be achieved through 3D printing technology. Using environmentally friendly materials such as polylactic acid to make parts in the construction of wind turbines reduces the pollution problems generated in the production process. This makes wind turbines a sustainable and environmentally friendly power generation device. The use of advanced materials reduces the mass of turbine components, which makes it much easier to transport and install. In addition to these advantages, transportation costs are also reduced because it no longer requires large transport vehicles and traffic disruption. © 2025 The Author(s).

关键词： Vertical axis wind turbine

来源：评论

学校读者我要写书评

暂无评论

AI Prediction of Power Grid Faults Based on Deep Learning and Improvement of Emergency Response Efficiency in Automated Repair

引用

Distributed Generation and Alternative Energy Journal 2025年第1期40卷 63-84页

作者： Huang, Di Zhu, Chaoyue Zheng, Weiyan Yan, Xingping Lu, Weimin Zhou, Bin Zhejiang Dayou Industrial Co. Ltd. Hangzhou Science and Technology Development Branch Zhejiang Hangzhou310000 China

This study aims to enhance the stability and reliability of power grids by proposing a deep learning-based emergency response method for power grid fault prediction and automated repair. We have constructed a fault prediction model capable of capturing the spatio-temporal characteristics of power grid data and the complex relationships between equipment. This model is designed to handle the heterogeneity of various data sources within the power grid, such as dissolved gas data and oil temperature data, and it independently analyzes these data to enhance prediction accuracy. Furthermore, based on Fourier transform technology, this study optimizes automated repair emergency response through frequency domain analysis. In simulations of a three-machine nine-node system, the proposed method has demonstrated improvements in fault detection speed, model interpretability, prediction accuracy, and response time delay. Specifically, the detection accuracy for single-phase-to-ground faults reached 94.7%, two-phase-to-phase faults 91%, two-phase-to-ground faults 95.4%, and three-phase faults 93%. Additionally, when considering the overall performance across these different fault types, the method achieved a comprehensive solution accuracy of 93.8% during the testing phase, which takes into account the detection rates of all mentioned fault types. The research method effectively enhances the accuracy of power grid fault prediction and the response speed of automated repair, providing strong technical support for the intelligent management and maintenance of power grids. The results of this study not only advance the development of power grid fault prediction technology in theory but also hold significant value and broad application prospects in practical applications. © 2025 River Publishers.

关键词： automated repair Deep learning fourier transform power grid fault prediction self attention mechanism

来源：评论

学校读者我要写书评

暂无评论

Research progress of slippage characteristic and gas film stability enhancement methods on biomimetic hydrophobic surfaces

引用

Journal of Hydrodynamics 2024年第1期36卷 87-101页

作者： Meng-zhuo Zhang Hai-bao Hu Liu-zhen Ren Lu-yao Bao Jun Wen Luo Xie School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an710072China Research and Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen518063China

The biomimetic hydrophobic surface is a potentially efficient underwater drag reduction method and the drag reduction mechanism of this kind of surface comes from the interfacial *** now,it is a hotspot to grasp the slippage characteristic and explore slippage enhancement *** paper not only summarizes our numerical simulation and experimental results of slippage characteristic at the solid-liquid interface(SLI)of hydrophobic surfaces(HS)and the gas-liquid interface(GLI)of superhydrophobic surfaces(SHS)in recent years,but also introduces some innovative methods that can effectively improve the gas film stability and drag reduction effect of ***,we used the molecular dynamics(MD)simulation method to figure out the effect of the solid-liquid interaction strength,the system temperature and the shear rate on the slippage of SLI,and expound their action mechanism from molecular ***,by MD and multibody dissipative particle dynamics(MDPD)method,the slippage behavior at the GLI was studied under the influence of the microstructure size and the flow driving *** proposed a new kind of hybrid slip boundary condition model to describe the slippage characteristic on *** addition,we found through experiment that a three-dimensional backflow will appear on the GLI under the interfacial adsorption of surfactants,and the backflow direction will reverse with the change of GLI ***,we put forward the wettability step structure and gas injection method to enhance the stability and drag reduction effect of the gas film on SHS.

关键词： Hydrophobic surface superhydrophobic surface interfacial slip underwater drag reduction

来源：评论

学校读者我要写书评

暂无评论

Coercivity enhancement of nanocrystalline Ce-based magnets utilizing simplified one-step hot deformation process

引用

Rare Metals 2025年第1期44卷 531-542页

作者： Xue-Feng Liao Qing Zhou Wei-Wei Zeng Bang Zhou Hong-Ya Yu Wei-Da Huang Wen-Bing Fan Jia-Sheng Zhang Zhong-Wu Liu School of Materials Science and Engineering South China University of TechnologyGuangzhou 510640China Guangdong Provincial Key Laboratory of Rare Earth Development and Application Institute of Resources Utilization and Rare Earth DevelopmentGuangdong Academy of SciencesGuangzhou 510640China

Nanocrystalline Ce-based rare earth(RE)-Fe-B alloys exhibit relatively good hard magnetic properties and high performance-cost ratio,but their properties deteriorate seriously after hot deformation(HD).Here,we present a simplified one-step HD process for preparing anisotropic Ce-based Ce_(25.88)La_(2.85)Y_(4.56)Fe_(65.73)B_(0.98)(wt%)*** precursor of nanocrystalline powders is first compacted inside a copper tube,and then the powders with the tube are deformed together to achieve magnetic *** with the conventional two-step HD magnet,i.e.,hot pressing followed by HD,one-step HD significantly increased the coercivity from 1.6 to 3.0 kOe,and the maximum magnetic energy product was improved from 3.7 to 4.8 *** microstructure characterization indicates that one-step HD can not only produce a more desirable microstructure,characterized by well-aligned platelet-shaped grains with reduced aspect ratio but also greatly inhibit the formation of coarse grain(CG)*** of them have been confirmed to be beneficial to enhancing coercivity by micromagnetic *** results thus demonstrate that the simplified one-step HD process offers a promising approach to developing high-performance anisotropic Ce-based magnets.

关键词： Hot deformation(HD) Ce-Fe-B Coercivity Coarse grain(CG) Aspect ratio

来源：评论

学校读者我要写书评

暂无评论

Energy-efficient computation offloading assisted by RIS-based UAV

引用

The Journal of China Universities of Posts and Telecommunications 2024年第1期31卷 37-48页

作者： Li Linpei Zhao Chuan Su Yu Huo Jiahao Huang Yao Li Haojin School of Intelligence Science and Technology University of Science and Technology BeijingBeijing 100083China Institute of Artificial Intelligence University of Science and Technology BeijingBeijing 100083China Shunde Innovation School University of Science and Technology BeijingFoshan 528399China School of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100083China Research Department of 5G and Drone China Mobile(Chengdu)Institute of Research and DevelopmentChengdu 610200China College of Communication Engineering Chengdu University of Information TechnologyChengdu 610225China Research and Development Center Sony(China)LimitedBeijing 100027China

The new applications surge with the rapid evolution of the mobile *** explosive growth of the data traffic aroused by the new applications has posed great computing pressure on the local *** is essential to innovate the computation offloading methods to alleviate the local computing burden and improve the offloading *** edge computing(MEC)assisted by reflecting intelligent surfaces(RIS)-based unmanned aerial vehicle(UAV)is a promising method to assist the users in executing the computation tasks in proximity at low *** this paper,we propose an energy-efficient MEC system assisted by RIS-based UAV,where the UAV with RIS mounted relays the computation tasks to the MEC *** energy efficiency maximization problem is formulated by jointly optimizing the UAV's trajectory,the transmission power of all users,and the phase shifts of the reflecting elements placed on the *** that the optimization problem is non-convex,we propose a deep deterministic policy gradient(DDPG)-based *** combining the DDPG algorithm with the energy efficiency maximization problem,the optimization problem can be ***,the numerical results are illustrated to show the performance of the system and the superiority compared with the benchmark schemes.

关键词： mobile edge computing unmanned aerial vehicle reflecting intelligent surface

来源：评论

学校读者我要写书评

暂无评论

Impact of land use change on carbon storage in the middle reaches of the Yellow River,China

引用

Journal of Arid Land 2025年第2期17卷 167-181页

作者： SHI Xiaoliang ZHANG Jie LIU Simin DING Hao CHEN Xi WANG Li ZHANG Dan College of Geomatics Xi'an University of Science and TechnologyXi'an 710054China China National Forestry-Grassland Development Research Center Beijing 100714China

The implementation of long-term shelterbelt programs in the middle reaches of the Yellow River(MRYR),China not only has improved the overall ecological environment,but also has led to the changes of land use pattern,causing carbon storage ***,the relationship between carbon storage and land use change in the MRYR is not concerned,which results in the uncertainty in the simulation of carbon storage in this *** use changes directly affect the carbon storage capacity of ecosystems,and as an indicator reflecting the overall state of land use,land use degree has an important relationship with carbon *** this study,land use data and the integrated valuation of ecosystem services and trade-offs(InVEST)model were used to assess the trends in land use degree and carbon storage in the MRYR during *** potential impact index and the standard deviation ellipse(SDE)algorithm were applied to quantify and analyze the characteristics of the impact of land use changes on carbon ***,land use transitions that led to carbon storage variations and their spatial variations were *** results showed that:(1)the most significant periods of carbon storage changes and land use transitions were observed during 1990-1995 and 1995-2020,with the most changed areas locating in the east of Fenhe River and in northwestern Henan Province;(2)the positive impact of land use degree on carbon storage may be related to the environmental protection measures implemented along the Yellow River,while the negative impact may be associated with the expansion of construction land in plain areas;and(3)the conversion of other land use types to grassland was the primary factor affecting carbon storage changes during *** future land use planning,attention should be given to the direction of grassland conversion,and focus on reasonably limiting the development of construction *** enhance carbon storage,it will be crucial to increase the area

关键词： carbon storage land use degree integrated valuation of ecosystem services and trade-offs(InVEST)model potential impact standard deviation ellipse(SDE)

来源：评论

学校读者我要写书评

暂无评论

High-speed penetration of ogive-nose projectiles into thick concrete targets:Tests and a projectile nose evolution model

引用

Defence technology（防务技术） 2024年第2期32卷 553-571页

作者： Xu Li Yan Liu Junbo Yan Zhenqing Shi Hongfu Wang Yingliang Xu Fenglei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing401120China China Research and Development Academy of Machinery Equipment Beijing100089China

The majority of the projectiles used in the hypersonic penetration study are solid flat-nosed cylindrical projectiles with a diameter of less than 20 *** study aims to fill the gap in the experimental and analytical study of the evolution of the nose shape of larger hollow projectiles under hypersonic *** the hypersonic penetration test,eight ogive-nose AerMet100 steel projectiles with a diameter of 40 mm were launched to hit concrete targets with impact velocities that ranged from 1351 to 1877 m/*** erosion of the projectiles was observed during high-speed penetration of heterogeneous targets,and apparent localized mushrooming occurred in the front nose of recovered *** examining the damage to projectiles,a linear relationship was found between the relative length reduction rate and the initial kinetic energy of projectiles in different penetration ***,microscopic analysis revealed the forming mechanism of the localized mushrooming phenomenon for eroding penetration,i.e.,material spall erosion abrasion mechanism,material flow and redistribution abrasion mechanism and localized radial upsetting deformation ***,a model of highspeed penetration that included erosion was established on the basis of a model of the evolution of the projectile nose that considers radial upsetting;the model was validated by test data from the literature and the present *** upon the impact velocity,v0,the projectile nose may behave as undistorted,radially distorted or *** to the effects of abrasion of the projectile and enhancement of radial upsetting on the duration and amplitude of the secondary rising segment in the pulse shape of projectile deceleration,the predicted DOP had an upper limit.

关键词： High-speed penetration Concrete target Erosion Projectile nose evolution model

来源：评论

学校读者我要写书评

暂无评论

Research on the quasi-isentropic driving model of aluminized explosives in the detonation wave propagation direction

引用

Defence technology（防务技术） 2024年第2期32卷 596-618页

作者： Hongfu Wang Yan Liu Fan Bai Chao He Yingliang Xu Qiang Zhou Chuan Xiao Fenglei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China China Research and Development Academy of Machinery Equipment Beijing100089China Beijing Institute of Technology Chongqing Innovation Center Chongqing401120China

Taking CL-20(Hexanitrohexaazaisowurtzitane)-based aluminized explosives with high gurney energy as the research object, this research experimentally investigates the work capability of different aluminized explosive formulations when driving metal flyer plates in the denotation wave propagation *** research results showed that the formulations with 43 μm aluminum(Al) powder particles(The particle sizes of Al powder were in the range of 2~43 μm) exhibited the optimal performance in driving flyer plates along the denotation wave propagation direction. Compared to the formulations with Al powder 13 μm, the formulations with Al powder 2 μm delivered better performance in accelerating metal flyer plates in the early stage, which, however, turned to be poor in the later stage. The CL-20-based explosives containing 25% Al far under-performed those containing 15% Al. Based on the proposed quasi-isentropic hypothesis, relevant isentropy theories, and the functional relationship between detonation parameters and entropy as well as Al reaction degree, the characteristic lines of aluminized explosives in accelerating flyer plates were theoretically studied, a quasi-isentropic theoretical model for the aluminized explosive driving the flyer plate was built and the calculation methods for the variations of flyer plate velocity, Al reaction degree, and detonation product parameters with time and axial positions were developed. The theoretical model built is verified by the experimental results of the CL-20-based aluminized explosive driving flyer plate. It was found that the model built could accurately calculate the variations of flyer plate velocity and Al reaction degree over time. In addition, how physical parameters including detonation product pressure and temperature varied with time and axial positions was identified. The action time of the positive pressure after the detonation of aluminized explosives was found prolonged and the downtrend of the temperature was

关键词： Aluminized explosive Flyer plate experiment Quasi-isentropic theoretical model Al reaction Driving characteristics

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：