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Comprehensive study on the spatial distribution of heavy metals and their environmental risks in high-sulfur coal gangue dumps in China

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Journal of Environmental Sciences 2024年第2期136卷 486-497页

作者： Yingbo dong Huan Lu Hai Lin School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants Beijing 100083China

The accumulation of coal gangue(CG)from coal mining is an important source of heavy metals(HMs)in *** spatial distribution and environment risk assessment are extremely important for the management and remediation of *** soil samples were collected from the high-sulfur CG site in northern China and analyzed for six *** results showed that the soil was heavily contaminated by Mn,Cr and Ni based on the Nemerow index,and posed seriously ecological risk depended on the geo-accumulation index,potential ecological risk index and risk assessment *** semi-variogram model and ordinary kriging interpolation accurately portrayed the spatial distribution of ***,Mn,and Cr were distributed by band diffusion,Ni was distributed by core,the distribution of Cu had obvious patchiness and Zn was more *** spatial autocorrelation indicated that all HMs had strong spatial *** BCR sequential extraction was employed to qualify the geochemical fractions of *** data indicated that Fe and Cr were dominated by residual fraction;Cu,Ni and Zn were dominated by reducible and oxidizable fractions;Mn was dominated by reducible and acid-extractable(25.38%-44.67%)*** correlation analysis showed that pH was the main control factor affecting the non-residue fractions of ***,acid production from high sulfur CG reduced soil pH by 2-3,which indirectly promoted the activity of ***,the conceptual model of HMs contamination at the CG site was proposed,which can be useful for the development of ecological remediation strategies.

关键词： High-sulfur coal gangue Soil contamination Heavy metals Spatial distribution Geochemical fractions Risk assessment

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Coordination for a Closed-loop Supply Chain with Recycling Platform Considering Dynamic Setting

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Journal of Systems Science and Systems Engineering 2024年第4期33卷 425-451页

作者： Zehua Xiang Ting Ji Lingfeng dong School of Management Zhejiang UniversityHangzhou310058China School of Business Hangzhou City UniversityHangzhou310015China Alibaba Business College Hangzhou Normal UniversityHangzhou311121China

This paper presents a dynamic closed-loop supply chain(CLSC)model,incorporating a manufacturer,a retailer,and an internet recycling platform(IRP),utilizing differential game theory while considering the forgetting effect of *** model encompasses factors such as the quality level of used products and Big Data marketing(BDM),comparing optimal equilibriums under decentralized and cooperative decision *** effectively coordinate the dynamic CLSC at each time point,we propose a revenue-sharing and cost-sharing(RSCS)combined *** addition to ensuring reasonable sharing of revenues and costs,this contract allows the manufacturer to flexibly adjust wholesale prices for final products and transfer prices for used products in order to distribute profits appropriately and achieve Pareto optimality within the CLSC ***,our results indicate that there exists a threshold for Big Data marketing efficiency;high-efficiency BDM not only facilitates increased recycling on Internet platforms but also reduces unit recycling costs for ***,when implementing the combined contract,Big Data marketing efficiency does not impact the transfer price paid by manufacturers to Internet recycling platforms.

关键词： Big Data marketing differential game closed-loop supply chain coordination internet recycling platform

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Analysis of the Oscillatory Flows of Multiple Shock Waves in a Constant Area Duct

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Journal of Thermal Science 2024年第3期33卷 794-806页

作者： K JAMES Jintu KIM Heuy dong Department of Mechanical Engineering Andong National UniversityAndong36729Republic of Korea CAD-IT Korea Co. Ltd.Seoul08591Republic of Korea

The oscillatory response of multiple shock waves to downstream perturbations in a supersonic flow is studied numerically in a rectangular *** shock waves are formed inside the duct at a shock Mach number of *** duct has an exit height of H,and the effect of duct resonance on multiple shock oscillations is investigated by attaching exit ducts of lengths 0H,50H,and *** downstream disturbance frequency varied from 10 Hz to 200 Hz to explore the oscillation characteristics of the multiple shock *** oscillatory response of shock waves under self-excited and forced oscillation conditions are analyzed in terms of wall static pressure,shock train leading-edge location,shock train length,and the size of the separation *** extent of the initial shock location increases with an increase in exit duct length for the self-excited oscillation *** analysis of the shock train leading edge and the spectral analysis of wall static pressure variations are *** variation in the shock train length is analyzed using the pressure ratio method for self-excited as well as forced *** RMS amplitude of the normalized shock train length(ζ_(ST))increases with an increase in the exit duct length for the self-excited oscillation *** the downstream perturbation frequency is increased,ζ_(ST)is decreased for exit duct *** all exit duct designs and downstream forcing frequencies,the size of the separation bubble grows and shrinks during the shock oscillations,demonstrating the dependence on duct resonance and forced oscillations.

关键词： shock train downstream disturbance supersonic flow shock wave boundary layer interaction duct resonance flow separation

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Combustion characteristics of millimeter-sized aluminum particles in fluidized bed under various O_(2)/CO_(2)/H_(2)O atmospheres Author links open overlay panel

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Particuology 2024年第8期91卷 315-322页

作者： Jialing Zhou Rui Zhang dong Liu Key Laboratory of Thermal Control of Electronic Equipment Ministry of Industry and Information TechnologyNanjing210094China Advanced Combustion Laboratory School of Energy and Power EngineeringNanjing University of Science and TechnologyNanjing210094China

Aluminum is an attractive alternative fuel,but it burns very inefficiently due to the formation of a dense Al_(2)O_(3)layer which prevents O_(2)from diffusion to the surface of Al *** previous experiments,the combustion of millimeter-sized Al(mAl)particles in the fluidized bed has achieved a substantial increase in the combustion efficiency,but further improvements are still *** this study,the effects of reaction atmosphere on the fluidized combustion of mAl particles were *** experiments with different O_(2)/H_(2)O/CO_(2)concentrations were *** experimental results indicate that the combustion efficiency of mAl particles in fluidized bed increases as the mole fraction of O_(2),H_(2)O or CO_(2)increases,and the highest combustion efficiency can reach 38.7%.After the analysis of the oxide film on the surface of aluminum particles,it was found that it is easier to generate the unstableθ-Al_(2)O_(3)under CO_(2)atmosphere,and it is easier to generate the unstableγ-Al_(2)O_(3)andθ-Al_(2)O_(3)under H_(2)O *** unstable Al_(2)O_(3)film is more likely to be abraded in the fluidized bed,which leads to the effective improvement of the combustion efficiency.

关键词： Al combustion Fluidized bed Atmosphere Combustion efficiency

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Analysis and experimental study on resistance-increasing behavior of composite high efficiency autonomous inflow control device

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Petroleum Science 2024年第2期21卷 1290-1304页

作者： Liang-Liang dong Yu-Lin Zhang School of Mechatronic Engineering Southwest Petroleum UniversityChengdu610500SichuanChina State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina Oil and Gas Equipment Technology Sharing and Service Platform of Sichuan ProvinceChengdu610500SichuanChina

Bottom water coning is the main reason to reduce the recovery of horizontal bottom water reservoir. By water coning, we mean the oil-water interface changes from a horizontal state to a mound-shaped cone and breaks through to the wellbore. Autonomous inflow control device(AICD) is an important instrument maintain normal production after bottom water coning, however, the resistance increasing ability of the swirl type AICD is insufficient at present, which seriously affects the water control effect. Aiming this problem, this paper designs a multi-stage resistance-increasing and composite type AICD. The separation mechanism of oil-water two phases in this structure, the resistance form of oil-water single phase and the resistance-increasing principle of water phase are analyzed. Establishing the dual-phase multi-stage separation and resistance-increasing model, and verified by measuring the throttling pressure drop and oil-water volume fraction of the AICD, it is found that the composite type AICD has the effect of ICD and AICD at the same time, which can balance the production rate of each well section at the initial stage of production, delay the occurrence of bottom water coning. In the middle and later stages of production, water-blocking can be effectively increased to achieve water control and stable *** structural sensitivity analysis, the influence law of various structural parameters on the water control performance of composite AICD was obtained. The simulation calculation results show that,compared with the existing swirl type AICD, composite AICD has higher sensitivity to moisture content,the water phase throttling pressure drop is increased by 4.5 times on average. The composite AICD is suitable for the entire stage of horizontal well production.

关键词： Water control Flow separation Flow resistance-increasing AICD device Simulation and experiment

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Meta-path reasoning of knowledge graph for commonsense question answering

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Frontiers of Computer Science 2024年第1期18卷 49-59页

作者： Miao ZHANG Tingting HE Ming dong National Engineering Research Center for E-Learning Central China Normal UniversityWuhan 430079China Hubei Provincial Key Laboratory of Artificial Intelligence and Smart Learning Central China Normal UniversityWuhan 430079China National Language Resources Monitoring&Research Center for Network Media Central China Normal UniversityWuhan 430079China School of Computer Central China Normal UniversityWuhan 430079China

Commonsense question answering(CQA)requires understanding and reasoning over QA context and related commonsense knowledge,such as a structured Knowledge Graph(KG).Existing studies combine language models and graph neural networks to model ***,traditional knowledge graph are mostly concept-based,ignoring direct path evidence necessary for accurate *** this paper,we propose MRGNN(Meta-path Reasoning Graph Neural Network),a novel model that comprehensively captures sequential semantic information from concepts and *** MRGNN,meta-paths are introduced as direct inference evidence and an original graph neural network is adopted to aggregate features from both concepts and paths *** conduct sufficient experiments on the CommonsenceQA and OpenBookQA datasets,showing the effectiveness of ***,we conduct further ablation experiments and explain the reasoning behavior through the case study.

关键词： question answering knowledge graph graph neural network meta-path reasoning

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设备复制系统的日志机制研究

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计算机工程与应用 2005年第5期41卷 18-21页

作者：王彦龙李战怀董欢庆林伟西北工业大学计算机学院西安71007

设备复制系统采用数据复制技术实现数据容灾,而日志机制是整个系统的核心和基础。本文在分析借鉴文件系统和数据库系统日志的基础上,提出了一个满足设备复制系统特点和设计要求的日志机制,并重点围绕日志的组织结构、生成方式、访问方... 详细信息

设备复制系统采用数据复制技术实现数据容灾,而日志机制是整个系统的核心和基础。本文在分析借鉴文件系统和数据库系统日志的基础上,提出了一个满足设备复制系统特点和设计要求的日志机制,并重点围绕日志的组织结构、生成方式、访问方式以及溢出、修正等特殊情况的处理方法进行了论述。原型实验表明,该日志机制在设备复制系统得到了较好实现,为数据复制提供了保障。

关键词：设备复制日志控制信息数据单元溢出重建

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EG-STC: An Efficient Secure Two-Party Computation Scheme Based on Embedded GPU for Artificial Intelligence Systems

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Computers, Materials & Continua 2024年第6期79卷 4021-4044页

作者： Zhenjiang dong Xin Ge Yuehua Huang Jiankuo dong Jiang Xu School of Computer Science Nanjing University of Posts and TelecommunicationsNanjing210023China School of Computer Nanjing University of Information Science and TechnologyNanjing210044China

This paper presents a comprehensive exploration into the integration of Internet of Things(IoT),big data analysis,cloud computing,and Artificial Intelligence(AI),which has led to an unprecedented era of *** delve into the emerging trend of machine learning on embedded devices,enabling tasks in resource-limited ***,the widespread adoption of machine learning raises significant privacy concerns,necessitating the development of privacy-preserving *** such technique,secure multi-party computation(MPC),allows collaborative computations without exposing private *** its potential,complex protocols and communication interactions hinder performance,especially on resource-constrained *** to enhance efficiency have been made,but scalability remains a *** the success of GPUs in deep learning,lever-aging embedded GPUs,such as those offered by NVIDIA,emerges as a promising ***,we propose an Embedded GPU-based Secure Two-party Computation(EG-STC)framework for Artificial Intelligence(AI)*** the best of our knowledge,this work represents the first endeavor to fully implement machine learning model training based on secure two-party computing on the Embedded GPU *** experimental results demonstrate the effectiveness of *** an embedded GPU with a power draw of 5 W,our implementation achieved a secure two-party matrix multiplication throughput of 5881.5 kilo-operations per millisecond(kops/ms),with an energy efficiency ratio of 1176.3 kops/ms/***,leveraging our EG-STC framework,we achieved an overall time acceleration ratio of 5–6 times compared to solutions running on server-grade *** solution also exhibited a reduced runtime,requiring only 60%to 70%of the runtime of previously best-known methods on the same *** summary,our research contributes to the advancement of secure and efficient machine learning implementations on resource-constrained embedded

关键词： Secure two-party computation embedded GPU acceleration privacy-preserving machine learning edge computing

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A Review on Particle Reinforced Mg Matrix Composites Fabricated by Powder Metallurgy

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 391-400页

作者： Zhiyuan Liu Li Jin Jian Zeng Fulin Wang Fenghua Wang Shuai dong Jie dong National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composite School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

This paper provides a comprehensive review of research progress in particle-reinforced Mg matrix composites prepared via powder *** article discusses different strategies,such as micro-sized,nano-sized particles,and multi-particle hybridization,which has been employed to enhance the performance of the *** addition,a range of preparation techniques that optimize the dispersion of the reinforcing particles are *** paper also highlights how the different configurations between the reinforcements and matrix alloy impact the composites’***,the article outlines the prospects of particles reinforced Mg matrix composites fabricated via powder metallurgy and recommends modification methods that could be explored to further develop these materials for various applications.

关键词： Magnesium matrix composites Reinforcing particle Powder metallurgy Mechanical properties Configuration

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Three-dimensional stability calculation method for high and large composite slopes formed by mining stope and inner dump in adjacent open pits

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International Journal of Mining Science and Technology 2024年第4期34卷 507-520页

作者： Zuchao Liang dong Wang Guanghe Li Guangyu Sun Mingyu Yu dong Xia Chunjian Ding College of Mining Engineering Liaoning Technical UniversityFuxin 123000China Inner Mongolia Pingxi Baiyinhua Coal Industry Co. Ltd.Xilingol League 026000China Guoneng Baorixile Energy Co. Ltd.Hulunbuir 021008China

The 2D limit equilibrium method is widely used for slope stability ***,with the advancement of dump engineering,composite slopes often exhibit significant 3D mechanical ***,it is of significant importance to develop an effective 3D stability calculation method for composite slopes to enhance the design and stability control of open-pit slope *** the composite slope formed by the mining stope and inner dump in Baiyinhua No.1 and No.2 open-pit coal mine as a case study,this research investigates the failure mode of composite slopes and establishes spatial shape equations for the sliding *** integrating the shear resistance and sliding force of each row of microstrip columns onto the bottom surface of the strip corresponding to the main sliding surface,a novel 2D equivalent physical and mechanical parameters analysis method for the strips on the main sliding surface of 3D sliding masses is ***,a comprehensive 3D stability calculation method for composite slopes is developed,and the quantitative relationship between the coordinated development distance and its 3D stability coefficients is *** analysis reveals that the failure mode of the composite slope is characterized by cutting-bedding sliding,with the arc serving as the side interface and the weak layer as the bottom interface,while the destabilization mechanism primarily involves shear *** spatial form equation of the sliding mass comprises an ellipsoid and weak plane *** analysis revealed that when the coordinated development distance is 1500 m,the error rate between the 3D stability calculation result and the 2D stability calculation result of the composite slope is less than 8%,thereby verifying the proposed analytical method of equivalent physical and mechanical parameters and the 3D stability calculation method for composite ***,the3D stability coefficient of the composite slope exhibits an exponential co

关键词： Composite slope Destabilization mechanism 3D mechanical effect Three-dimensional stability Coordinated development distance

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